2015 Annual Report

Sustainable 

Transportation 

Program

ORNL/SR-2016/402
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2016-G00496/cae

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ORNL/SR-2016/402

Sustainable Transportation Program

2015 Annual Report

Compiled by

Kim Askey

for

Claus Daniel, Acting Director

ORNL Sustainable Transportation Program

Date Published: August 2016

Prepared by

OAK RIDGE NATIONAL LABORATORY

Oak Ridge, TN 37831-6283

managed by

UT-BATTELLE, LLC

for the

U.S. DEPARTMENT OF ENERGY

under contract DE-AC05-00OR22725
2015 Annual Report Contents

ORNL Sustainable Transportation Program iii

Table of Contents

Introduction................................................................................................................................................. 1

Program Metrics.................................................................................................................................... 3

Funding ......................................................................................................................................... 3

Industry Impact ............................................................................................................................. 4

CRADAS....................................................................................................................................... 4

Strategic Partnership Projects........................................................................................................ 4

Laboratory-Directed Research and Development ......................................................................... 5

Patents........................................................................................................................................... 6

Staff Awards and Honors.............................................................................................................. 7

Infrastructure and Facility Investments......................................................................................... 9

Bioenergy Technologies R&D Highlights............................................................................................... 11

Key Findings Show Benefits of High-Octane Fuels........................................................................... 11

Groundbreaking ORNL Compatibility Work Used by Industry and Government ............................. 12

ORNL Develops International Fire Codes for the Bioenergy Industry............................................... 14

ORNL-Led Consortium Leverages DOE Resources to Advance Biofuels Production; 

Impacts Feedstock Variations on Carbon Yield, Composition in Pyrolysis Oil ......................... 15

Study Explains Underlying Process Behind Biofuel-to-Hydrocarbon Conversion Technology ........ 16

DOT R&D Highlights............................................................................................................................... 19

ORNL Completes Pilot Phase of System to Thwart Fuel Tax Evaders.............................................. 19

Private and Secure Connected Vehicle Communications Leads to Safer Transportation................... 20

Wireless Roadside Inspection Project Improves Safety and Efficiency for Trucks and Buses .......... 22

Fuel Cell Technologies R&D Highlights................................................................................................. 25

Analysis of Hydrogen Fuel Cell Onboard Storage Pressure ............................................................... 25

Imaging and Microanalysis of Thin Ionomer Layers Using Advanced Microscopy 

Techniques .................................................................................................................................. 26

Impact of Iridium-Ruthenium Oxygen Evolution Reaction Catalysts on PEMFC Electrode 

Catalysts...................................................................................................................................... 27

Melt-Spun Polyacrylonitrile for High-Strength Compressed Hydrogen Storage Systems................. 29

Vehicle Technologies R&D Highlights.................................................................................................... 31

Analysis..............................................................................................................................................31

MA3

T Model Continues to Grow in Richness and Use .................................................................31

ORNL Fuel Economy Information Project Accomplishments......................................................32

Combustion, Engines, and Fuels......................................................................................................34

Advanced Control Strategies Key to Extending Dilution Limits in Light-Duty Vehicles.............34

Cross-Cut Lean Exhaust Emissions Reduction Simulations Analysis and Coordination..............35

Improving Vehicle Fuel Economy through Increasing Fuel Octane Ratings ................................38

Low-Temperature Emissions Control............................................................................................39

Neutron Imaging of Advanced Vehicle Technologies...................................................................43

ORNL Investigates How New Fuels and Lubricants Affect Emission Systems............................45

Stretching Internal Combustion Engine Efficiency with New Combustion Regimes...................46

Using Advanced Fuels in Advanced Combustion Regimes ..........................................................49

Using High-Performance Computing to Accelerate Engine Development ...................................52

Energy Storage ..................................................................................................................................54

Nondestructive Evaluation Techniques for Processing High-Energy Lithium Ion Batteries ........54

Patented Aqueous Processing Technology Demonstrates Performance and Durability................55

State-of-the-Art Diagnostics Applied to High Voltage, High Capacity LithiumManganese-Rich Cathodes.....................................................................................................57
Contents 2015 Annual Report

iv ORNL Sustainable Transportation Program

Lightweight Materials.......................................................................................................................59

Advanced Oxidative Stabilization of Carbon Fiber Precursors.....................................................59

Better Predictive Engineering Tools for Improved Thermoplastic Composites............................60

Corrosivity and Passivity of Metastable Magnesium Alloys.........................................................61

DOE Carbon Fiber Technology Facility Continues to Chart Low-Cost Fiber Course ..................62

Laser-Assisted Joining Process for Aluminum and Carbon Fiber Components Enables 

Use in Primary Automotive Structures..................................................................................64

Enabling Multimaterial Next-Generation Vehicles .......................................................................65

Power Electronics and Electric Motors...........................................................................................70

ORNL Demonstrates 10 kW Bidirectional Wireless Power Transfer System...............................70

ORNL’s Innovative Onboard Battery Charger Technology: Double the Power Density at 

Half the Cost ..........................................................................................................................72

Sintered-Silver Interconnect Technology for High-Performance Wide-Bandgap Devices...........73

USDrive–DOE, Delphi Partner on New Chevrolet Volt Inverter..................................................75

Propulsion Materials.........................................................................................................................76

Stronger, Lower Cost Alloys for Higher Temperature Exhaust Valves Improve Vehicle 

Efficiency...............................................................................................................................76

Novel In Situ Electron Microscopy Developed for Characterizing Catalyst Behavior 

Under “Real” Reaction Conditions........................................................................................77

ORNL Develops Advanced Alloys for Turbochargers and Manifolds..........................................78

ORNL, Industry Partners Use High-Performance Computing to Drive Alloy Design..................79

Vehicle Systems.................................................................................................................................81

Advanced Combustion and Emission Control Technology Analysis and Evaluation...................81

Fleet DNA Database Development and Support ...........................................................................83

MD and HD Accessory Hybridization for Fuel Savings and Emissions Control..........................84

ORNL Collecting Important Data on Electric Vehicle Charging ..................................................85

Powertrain Controls Optimization for Heavy-Duty Hybrid Line Haul Trucks .............................86

Vehicle Technologies Office Communications ...............................................................................88

ORNL Publications Support Outreach Efforts and Meet Data Needs of the DOE Vehicle 

Technologies Office...............................................................................................................88
Introduction

ORNL Sustainable Transportation Program 1

Introduction

Oak Ridge National Laboratory’s (ORNL’s) Sustainable Transportation Program (STP) brings together 

science and technology experts from across scientific disciplines to partner with government and industry 

in addressing national transportation challenges. STP develops knowledge and technologies that 

accelerate the deployment of new vehicles and efficient transportation systems powered by domestic, 

renewable, clean energy.

The Program’s research and development (R&D) portfolio includes vehicle systems integration, fuel and 

lubricant technologies, advanced combustion engines, innovative materials, intelligent transportation 

systems, efficient vehicle components, and transportation electrification. Millions of vehicles on the road 

today are more durable and more efficient because of ORNL-developed materials technologies.

ORNL also provides data and analysis to guide policies and strategic decisions of the Department of 

Energy (DOE) Office of Energy Efficiency and Renewable Energy (EERE) and other branches of 

government. Policy makers, industry leaders, and consumers make transportation decisions every day 

using data collected and analyzed by ORNL.

The Program’s primary support comes from DOE EERE through the Vehicle Technologies Office (VTO), 

Bioenergy Technologies Office (BETO), and Fuel Cell Technologies Office (FCTO). Support also comes 

from the Department of Transportation (DOT), other federal agencies, and the private sector. ORNL 

supports the US DRIVE (Driving Research and Innovation for Vehicle efficiency and Energy 

sustainability) and the 21st Century Truck government–industry partnerships, as well as DOE’s EV 

Everywhere Grand Challenge and other sustainable transportation efforts. 

STP pursues an “all of the above” strategy that incorporates 

• accelerating widespread use of electric vehicles (EVs) powered by both batteries and fuel cells;

• increasing the efficiency of all types of vehicles through lighter materials and advanced combustion 

and powertrain technologies;

• enabling widespread use of cleaner fuels such as biofuels and natural gas; and

• collecting, analyzing, and disseminating data to support efficient commercial fleet operation, 

intelligent systems, congestion management, and informed decision-making.

These efforts are directed toward attaining 

• efficient, secure, affordable vehicles for passengers and freight;

• domestic production of transportation fuel;

• reduction of the environmental impacts of transportation; and

• predictability and reliability in transport scheduling. 

Transportation is a key factor in the energy and environmental future of the United States. Highway 

transportation (light-, medium-, and heavy-duty vehicles) accounted for about 27% of US greenhouse gas 

emissions and about 58% of US petroleum consumption. Although energy use by light-duty passenger 

vehicles is projected to decline by about 20% by 2040—largely as a result of more stringent greenhouse 

gas and corporate average fuel economy regulations—commercial light-duty trucks and heavy trucks are 

projected to use 21% more energy in 2040 than in 2015.
Introduction 2015 Annual Report

2 ORNL Sustainable Transportation Program

A sustainable transportation system that increases efficiency, cuts pollution associated with vehicle use 

and production, relies more on renewable fuels, and increases highway safety is an indispensable part of a 

sustainable future. 

With funding from BETO in FY 2015, ORNL led a multilaboratory effort focused on high-octane fuels, 

which found that mid-level ethanol blends used in engines that are optimized for the fuel can achieve 

vehicle performance benefits, realize better fuel economy, and lower greenhouse gas emissions. In 

another BETO-funded project, researchers explained the mechanism behind a technology that converts 

bio-based ethanol into hydrocarbon blend-stocks for use as fossil fuels. They found that the underlying 

reaction unfolds in a different manner than previously thought, with potential positive implications for the 

energy efficiency and cost of catalytic upgrading technologies proposed for use in biorefineries. A key 

compatibility study conducted by ORNL on ethanol and infrastructure materials was cited in the Federal 

Register in reference to regulations for underground storage tanks. Research on the safe storage of 

feedstocks determined how factors such as feedstock type and bale size, shape, and spacing affect the 

speed at which a biomass fire can spread. These experimental results have informed multiple changes to 

the International Building Code. 

In research supporting DOT, ORNL and its industry partners completed the pilot test phase for an 

onboard monitoring system for fuel trucks to prevent fuel tax evasion. The system tracks the movements 

of fuel tankers from bulk storage to final destination in real time to prevent blending of taxable and 

nontaxable fuels and other tax evasion attempts. Researchers also worked with DOT to examine security 

and privacy issues associated with vehicle-to-vehicle and vehicle-to-infrastructure connectivity. One 

project assessed the feasibility of building a vehicle-based credential verification system to ensure the 

validity of communications for connected vehicles. Another project focused on preserving privacy 

through developing algorithms for vehicle trajectory information that remove identifying characteristics 

from data while retaining the usefulness of the data.

ORNL research sponsored by FCTO included advanced characterization of catalysts and thin ionomer 

layers for fuel cells. One study focused on the effects of atomic-level changes to the structure and 

chemistry of Ir-Ru oxygen evolution reaction catalysts, identifying which catalyst pairs improved longterm durability through repeated cycles of starting up and shutting down. Another study determined 

optimized conditions for imaging and spectroscopic analysis of perfluorosulfonic acid ionomer thin films 

within fuel cell electrodes, defining best practices and enabling new insights that could lead to higherperformance fuel cells. ORNL also worked with Virginia Tech to produce melt-spun carbon fibers of up 

to 25 Msi modulus and 250 ksi strength. The melt-spinning approach could save 25% of the costs 

associated with producing carbon fiber for high-pressure hydrogen storage systems. 

With funding from VTO, researchers assisted Delphi in developing power electronics packaging for an 

improved traction drive inverter used in the second-generation Chevrolet Volt EV. ORNL also worked 

with industry to develop a novel device for in situ atomic microscopy at up to 1 atm of pressure, enabling 

new research avenues for catalysts and other applications. In another VTO project, researchers developed 

and demonstrated the world’s first bidirectional wireless power transfer system for level 2 (10 kW) 

charging. The bidirectional wireless charging system enabled a vehicle to power a building and vice versa 

as part of an integrated energy system. Projects focused on internal combustion, energy storage, and new 

alloys used high-performance computing to accelerate knowledge discovery and technology development. 

Neutron imaging captured cavitation events inside the nozzle of fuel injectors, informing injector design 

for greater fuel efficiency. Researchers conducted experiments to validate new models for the design of 

lightweight automotive structural components made with carbon fiber-reinforced injection-molded 

thermoplastics. Using infrared thermography, researchers are developing an evaluation process for battery 

electrodes and other roll-to-roll manufactured products that allows examination of materials on the 

production line to ensure quality without destroying the integrity of the examined material. Researchers 

also continued a multifaceted approach to developing optimized controls for an advanced hybrid heavy-
2015 Annual Report Introduction

ORNL Sustainable Transportation Program 3

duty powertrain that could decrease energy consumption and pollutant emissions in Class 8 line haul

vehicles.

Highlights of these and other STP R&D efforts begin on page 12.

Program Metrics

Funding

STP received $80.1 million in new budget funding in FY 2015. Approximately $12.5 million or 16% is

awarded competitively through Funding Opportunity Announcements. DOE VTO was the largest sponsor

of the ORNL program. Funding from industry, academia, and other nongovernment partners increased in 

FY 2015 compared with the previous year.

Program funding provided significant support for 154 scientific and technical staff in 10 technical

divisions, reflecting the multidisciplinary character of the ORNL program. STP team leaders are shown in 

the following organization chart.
Introduction 2015 Annual Report

4 ORNL Sustainable Transportation Program

Industry Impact

ORNL’s STP conducts most of its R&D in collaboration with industry so that pathways to 

commercialization are built into projects from the beginning. Industry partnerships are carried out through 

a variety of mechanisms, including cooperative research and development agreements (CRADAs), 

Strategic Partnership Project agreements, technology licensing, User Facility Agreements, and informal 

collaborations and information exchanges at technical conferences and workshops.

CRADAS

STP researchers supported 19 CRADAs in FY 2015 with 16 different companies, developing an array of 

transportation-related technologies. Industry partners contributed about $4.2 million in materials and 

services to those efforts.

Strategic Partnership Projects

ORNL worked with 60 industrial companies, 22 federal and state government entities, 9 nonprofit 

organizations, and 14 universities under 121 separate Strategic Partnership Project agreements in FY 

2015. Those agreements were valued at about $12.5 million in total.
2015 Annual Report Introduction

ORNL Sustainable Transportation Program 5

Laboratory-Directed Research and Development

ORNL’s Laboratory-Directed Research and Development (LDRD) initiative supports cutting-edge 

research with the objective of maintaining the vitality of the laboratory, enhancing the laboratory’s ability 

to address future DOE missions, and stimulating exploration at the forefront of science and 

technology. The transportation-related projects listed in Table 1 received LDRD awards in FY 2015.

Table 1. FY 2015 LDRD awards

Principal 

Investigator

Project 

Type/ID 

No.

Title Type of Research FY15 Funding

Todd Toops 6814 Dynamic Neutron Imaging of Intranozzle Fluid Dynamics of Fuel 

Injectors

Basic Research $475,000.00 

Nance Ericson 6923 Complementary Silicon Carbide Wide 

Bandgap Integrated Circuits for 

Bidirectional Electric Vehicle 

Chargers

Applied Research $320,000.00

Mircea Podar 6944 Transformative Process for Coupling 

Solar Energy to Biofuel Production in 

Yeast for Steady State Bioconversion 

Reactors

Basic Research $310,000.00 

Balasubram 

Radhakrishnan

7238 Fundamental Understanding of 

Banded Structure Formation during 

Laser Additive Manufacturing of a 

Titanium Alloy using Massively 

Parallel Phase Field Simulations

Basic Research $51,185.00

Xiao-Guang Sun 7315 Developing Hydroxide Fuel Cells 

Based on Novel Polymers with 

Improved Stability and Higher Ionic 

Conductivity

Applied Research $170,000.00

Andreas 

Malikopoulos

7396 Scalable Data and Informatics for 

Connected Vehicles Leveraged to 

Enhance Efficiency

Basic Research $385,000.00 

Gerald Tuskan 7428 Increasing Advanced Biofuels 

Production from Terpenes in 

Eucalyptus Leaves

Basic Research $325,000.00 

Joseph Raetano 7340 Transportation Security: Trustworthy 

Vehicle Computing System

Applied Research $385,000.00 

Daniel Close 7570 Characterization of InulinaseExpressing Saccharomyces cerevisiae

Strains for the Consolidated 

Bioprocessing of Agave Feedstocks

Biosciences 

Division

$190,000.00

Burak Ozpineci 6928 Next Generation Compact and 

Reliable WBG-Based Inverter 

Breakthrough with Additive 

Manufacturing and High Performance 

Computing

Applied Research $340,000.00 
Introduction 2015 Annual Report

6 ORNL Sustainable Transportation Program

Patents

Table 2. Patents awarded during FY 2015

Inventor Patent 

Number Title

Chengdu Liang, Nancy J. Dudney, and 

Jane Y. Howe 

9,023,528 Sulfur-Carbon Nanocomposites and Their Application 

as Cathode Materials in Lithium-Sulfur Batteries

Chengdu Liang, Zengcai Liu, Wujun Fu, 

Zhan Lin, Nancy J. Dudney, Jane Y. Howe, 

and Adam J. Rondinone

8,871,391 Lithium Sulfide Compositions for Battery Electrolyte 

and Battery Electrode Coatings 

Zhenxian Liang, Laura D. Marlino, Puqi Ning, 

and Fei Wang

9,041,183 Power Module Packaging with Double Sided Planar 

Interconnection and Heat Exchangers

John Miller and Perry T. Jones 9,035,790 Wireless Power Transfer Electric Vehicle Supply 

Equipment Installation and Validation Tool

William P. Partridge, Jr.; James E. Parks, II; 

and Ji Hyung Yoo

9,068,933 EGR Distribution and Fluctuation Probe Based on Co2

Measurements

William Partridge Jr.; James E. Parks, II; and 

Ji Hyung Yoo 

9,000,374 EGR Distribution and Fluctuation Probe Based on CO2

Measurements

Chaitanya Narula and Xiaofan Yang 8,987,161 Zeolite Based SCR Catalysts and Their Use in Diesel 

Engine Emission Treatment

Chaitanya Narula and Xiaofan Yang 8,987,162 Hydrothermally Stable, Low-Temperature NOx 

Reduction NH3-SCR Catalyst

Amit Naskar, Marcus A. Hunt, and 

Tomonori Saito

9,096,955 Method for the Preparation of Carbon Fiber from 

Polyolefin Fiber Precursor, and Carbon Fibers Made 

Thereby

Claus Daniel, Jianlin Li, Beth L. Armstrong, 

and David L. Wood, III

8,956,688 Aqueous Processing of Composite Lithium Ion 

Electrode Material

Claus Daniel 9,012,803 Method of Varying a Physical Property of a Material 

Through its Depth

Amit Naskar 9,096,959 Method for Production of Carbon Nanofiber Mat or 

Carbon Paper

Jae-Soon Choi, Beth Armstrong, and Vivian 

Schwartz

9,012,349 Method of Synthesizing Bulk Transition Metal 

Carbide, Nitride, and Phosphide Catalysts

Table 3. Patent applications filed during FY 2015

Inventor Patent Docket 

Number Title

Chengdu Liang 201403349 Electrochemically Stable Li7P2S8I Superionic Conductor

Chengdu Liang 201403404 Polyarene Mediators for Mediated Redox Flow Battery

Chengdu Liang 201303224 All-Solid-State Lithium Carbon Monofluoride Batteries

Sheng Dai and XiaoGuang Sun201503486 Nanoconfined Electrolytes and Their Use in Batteries

Mariappan 

Paranthaman and Amit 

Naskar

201503528 Carbon-Metal Oxide Composite Materials and Their Use in 

Anodes of Lithium and Sodium Ion Batteries
2015 Annual Report Introduction

ORNL Sustainable Transportation Program 7

Table 3. (continued)

Inventor Patent Docket 

Number Title

Omer Onar and John 

Miller

201202956 Buffering Energy Storage Systems for Reduced Grid and 

Vehicle Battery Stress for In-Motion Wireless Power Transfer 

Systems

William Partridge Jr.,

James Parks II, and 

Gurneesh Jatana

201303118 Diagnostic System for Measuring Temperature, Pressure, CO2

Concentration and H2O Concentration in a Fluid Stream

Clifford White, John 

Miller, Omer Onar, Paul 

Chambon, Lixin Tang, 

and Perry T. Jones

201303196 Overvoltage Protection System for Wireless Power Transfer 

Systems

Charles Warren, Claus 

Daniel, Adrian Sabau, 

Jian Chen, and Donald 

Erdman III

201403405 Nanostructured Surface Preparation for Joining Dissimilar 

Materials

Felix Paulauskas and 

Amit Naskar

200902241 Advanced Oxidation Method for Producing High-Density 

Oxidized Polyacrylonitrile Fibers

Soydan Ozcan and Amit 

Naskar

201303091 Method of Manufacturing Tin-Doped Indium Oxide Nanofibers

Zhili Feng and Stan 

David

201403240 Welding Method for Hydrogen Embrittlement Control

Govindarajan 

Muralidharan and Bruce 

Pint

201403395 Alumina-Forming, High Temperature Creep Resistant Ni-Based 

Alloys

Amit Naskar and Chau 

Tran

201403426 High Performance Lignin-Acrylonitrile Polymer Blend 

Materials

Mariappan Paranthaman 

and Amit Naskar

201503527 Highly Flexible and Low-Cost Conductive Carbon/Polymer 

Composite Paper as Ultra-Long Cycle Life Pseudocapacitive 

Electrode

Staff Awards and Honors

Research staff working on STP projects were recognized with a number of awards and professional 

honors reflecting significant contributions to research, technology development, and service to 

professional societies. A selection of the most prominent awards is presented in Table 4. 
Introduction 2015 Annual Report

8 ORNL Sustainable Transportation Program

Table 4. Significant awards and honors received by STP researchers

ORNL Awardee Name(s) Name/Type of Award

Curt Ayers, Steven Campbell, 

Madhu Chinthavali, Burak

Ozpineci, and Randy Wiles

Distinguished Achievement Award for 3D printed electric drive inverter, DOE 

Vehicle Technologies Office

Robert Bowman Award for Outstanding Achievement, DOE Fuel Cell Technologies Office

Michael Brady 2015 Brimacombe Medalist Award, The Minerals, Metals, and Materials 

Society

Tim Burress Appointed chair for Institute of Electrical and Electronics Engineers Standard 

11, “IEEE Standard for Rotating Electric Machinery for Rail and Road 

Vehicles”

Madhu Chinthavali Tech-to-market Excellence, Special Recognition from DOE Assistant Secretary 

for Energy Efficiency and Renewable Energy

Scott Curran Forest R. McFarland Award, SAE International

Stefan Pischinger Young Industry Leadership Award, SAE Foundation

Sujit Das Forest R. McFarland Award, SAE International

Appointed to the Transportation Research Board Committees on Transportation 

Economics and Alternative Transportation Fuels and Technologies

Nancy Dudney Corporate Fellow, ORNL

Zhili Feng Tech-to-market Excellence, Special Recognition from DOE Assistant Secretary 

for Energy Efficiency and Renewable Energy

Michael Kass Appointed to serve on the UL Renewable Energy Council

Jan-Mou Li Appointed to the Transportation Research Board Urban Transportation Data and 

Information Systems Committee

Changzheng Liu Best Presentation at the 28th International Electric Vehicle Symposium and 

Exhibition

Andreas Malikopoulos Appointed Secretary, Model Identification and Intelligent Systems Technical 

Committee, ASME Dynamic Systems and Control Division

James Parks, II Associate Editor, Frontiers in Engine and Automotive Engineering

William Partridge Jr., Tech-to-market Excellence, Special Recognition from DOE Assistant Secretary 

for Energy Efficiency and Renewable Energy

Jun Qu Associate Editor, Frontiers in Engine and Automotive Engineering

Scott Sluder Lloyd L. Withrow, Distinguished Speaker Award, SAE International

Editorial Board, Journal of Fuels and Lubricants

Appointed to Government/Industry Meeting General Committee, SAE 

International

Derek Splitter Forest R. McFarland Award, SAE International

2014 Myers Award, SAE International

Gui-Jia Su Tech-to-market Excellence, Special Recognition from DOE Assistant Secretary 

for Energy Efficiency and Renewable Energy

James Szybist Harry L. Horning Award, SAE International

John Thomas Editorial Board, Journal of Fuels and Lubricants
2015 Annual Report Introduction

ORNL Sustainable Transportation Program 9

Table 4. (continued)

ORNL Awardee Name(s) Name/Type of Award

Robert Wagner Associate Editor, Frontiers in Engine and Automotive Engineering

Co-Editor, International Journal of Engine Research

Appointed to Executive Committee, SAE International Powertrain Fuels and 

Lubricants Technical Committee 

Brian West Harry L. Horning Award, SAE International

Appointed to Fellows Selection Committee, SAE International

Martin Wissink 2014 Myers Award, SAE International

Thomas Zawodzinski Fellow, American Chemical Society

Royal Academy of Engineering Distinguished Visiting Fellowship

Infrastructure and Facility Investments

New Laboratory for Vehicle Cyber Security R&D. A new laboratory focused on vehicle cyber security 

has been installed at ORNL’s National Transportation Research Center. The Vehicle Cyber Security 

Laboratory offers a suite of capabilities to assess cyber vulnerabilities while vehicles are in operation. It 

includes a full vehicle dynamometer with specialized scanning equipment (controller area network 

communications analysis and calibration tools for electronic control units) in a space with signal isolation, 

ensuring data integrity. The lab has been established, and major equipment has been installed. C

commissioning is scheduled for early FY16.

The new laboratory is part of ORNL’s Vehicle Security Center (VSC), which brings together expertise 

and facilities from across the laboratory to address the emerging national transportation challenge 

presented by modern vehicles that are increasingly computerized and connected. The VSC assesses 

potential threat vectors for cyber attack in automotive systems and partners with industry to engineer 

secure solutions for new vehicles before they hit the road. The main focus of the VSC is predictive 

assessment. 

VSC capabilities include

• prototyping, 

• malware discovery, 

• large-scale data analysis, 

• vehicle security assessment for current and future vehicles, 

• anti-tamper and encryption devices, 

• authentication and privacy protections, 

• reverse engineering of embedded systems, and 

• vehicle-based credential generation.

New magnetic properties observation system implemented. A new observation system that provides 

high-resolution analysis of localized magnetic properties was implemented in the Power Electronics and 

Electric Machinery Laboratory. The system was designed primarily to investigate properties of soft 

magnetic materials such as silicon steel laminations that are used in electric motors, but it can also be 

used on many other types of magnetic materials. This system complements the custom characterization 
Introduction 2015 Annual Report

10 ORNL Sustainable Transportation Program

system previously developed by providing higher resolution and therefore increased insight into the 

fundamental phenomena of electrical steel. The previously developed system is more advantageous for 

high-level observations.

Dithering flow reactor: new capability in the Fuels, Engines, and Emissions Research Center.

Researchers designed, constructed, and commissioned a new automated flow reactor system with fast 

transient flow control and instrumentation capabilities that enable rapid oscillations in gas composition 

similar to those seen in exhaust from stoichiometric combustion in gasoline and natural gas engines.

Capturing these oscillations, known as dithering, is a key capability for evaluating three-way catalyst 

materials that will play a critical role in achieving emissions compliance with future high-efficiency 

engine technologies, such as highly dilute stoichiometric or lean gasoline engines. 

ORNL installs new demonstration line in Battery Manufacturing Facility. Scientists completed the 

installation and trial run of the new battery electrode ultraviolet (UV) curing system with assistance from 

Conquip and Miltec engineers. Required system modifications are ongoing. The UV curing process 

promises substantial gains in production efficiency and cost savings of more than 50% vs. conventional 

solvent-drying systems. 

State-of-the-art dynamometer to advance engine research. ORNL is upgrading Engine Cell 5 in the 

Fuels, Engines, and Emissions Research Center with a state-of-the-art dynamometer to support current 

and next-generation advanced engine development, including hardware-in-the-loop capability for 

advanced controls development.
Bioenergy Technologies R&D Highlights

ORNL Sustainable Transportation Program 11

Bioenergy Technologies R&D 

Highlights Key Findings Show Benefits of High-Octane Fuels

Contact: Timothy J. Theiss, theisstj@ornl.gov, 865-946-1348

Scientists at ORNL have been working with colleagues at Argonne National Laboratory, the National 

Renewable Energy Laboratory (NREL), and automakers to assess the benefits of high-octane midlevel 

(E25 to E40) ethanol blends, barriers to their adoption, and strategies for introducing them.

Automakers have long known that boosting the octane level of fuels can translate to performance benefits 

such as faster acceleration, improved fuel economy, or greater towing capacity. Ethanol, which has a 

higher octane rating and higher heat of vaporization than gasoline, is an effective octane booster. It has 

the added benefit of reducing use of petroleum-based fuels and greenhouse gas emissions. Through a 

series of studies, ORNL, Argonne, and NREL researchers have demonstrated that multiple benefits can be 

garnered when high-octane midlevel ethanol blends are used in vehicles designed for these fuels with 

innovations such as direct injection, higher compression ratio, downspeeding, downsizing, and 

turbocharging.

The following are among the most significant findings and outcomes from the 2-year Bioenergy 

Technologies Office study, which will end in early 2016.

• Fuel efficiency gains of up to 10% over E10 were demonstrated with high-octane E30 in a vehicle 

with a turbocharged direct injection engine. Such efficiency gains can offset the lower energy density 

of high-octane ethanol blends compared to gasoline or E10.

• High-octane midlevel ethanol blends offer a performance benefit (improved acceleration) compared 

to E10 for most legacy flexible-fuel vehicles, with no engine modifications. This finding could help 

establish consumer demand for these fuels and ease the transition to a new fueling infrastructure and 

new vehicles designed for high-octane fuels.

• Using a gasoline blend containing 40% ethanol (E40) generated from cellulosic feedstocks such as 

corn stover or other nonedible sources of biomass could reduce greenhouse gas (GHG) emissions by 

30%. E25 and other ethanol blends were also analyzed, and all lowered GHG emissions compared to 

fuel with no ethanol, although smaller benefits were realized for lower concentrations of ethanol.

• Compatibility studies confirm that currently available materials are viable for use in the fueling 

infrastructure with midlevel ethanol fuel blends.

Using models, including ORNL’s MA3T (Market Acceptance of Advanced Automotive Technologies), 

researchers have evaluated the market conditions and potential consumer acceptance for high-octane-fuel 

vehicles. The studies show these vehicles can be market competitive. They are attractive in part because 

the fuel they require is projected to cost no more than E10. 

Complementary work is continuing under the Bioenergy Technologies Office and Vehicle Technologies 

Office Co-Optimization of Fuels and Engines Initiative (http://energy.gov/eere/bioenergy/cooptimization-fuels-engines), looking not only at high-octane fuels for advanced spark-ignition engines, 

but also at exploring new bio-derived fuels for advanced compression-ignition engines.

Publications, Presentations, and Patents

(Note: Where authors were from multiple organizations, ORNL author names have been bolded.)

1. J. F. Thomas, B. H. West, and S. P. Huff. 2015. Effects of High Octane Ethanol Blends on Four 

Legacy Flex-Fuel Vehicles and a Turbocharged GDI Vehicle. ORNL/TM-2015/116, Oak Ridge 
Bioenergy Technologies R&D Highlights 2015 Annual Report 

12 ORNL Sustainable Transportation Program 

National Laboratory, Oak Ridge, Tennessee; available at 

http://info.ornl.gov/sites/publications/Files/Pub54888.pdf. 

2. T. J. Theiss, T. Alleman, A. Brooker, A. Elgowainy, G. Fioroni, J.Han, S. Huff, C. Johnson, M. 

Kass, P. Leiby, R. Martinez, R. McCormick, K. Moriarty, E. Newes, G. Oladosu, J. Szybist, J. 

Thomas, M. Wang, and B. West. 2016. Summary of High-Octane Mid-Level Ethanol Blends Study. 

ORNL/TM-2016/42, Oak Ridge National Laboratory, Oak Ridge, Tennessee. 

3. K. Moriarty, M. Kass, and T. Theiss. 2014. Increasing Biofuel Deployment and Utilization through 

Development of Renewable Super Premium: Infrastructure Assessment. NREL/TP-5400-61684, 

National Renewable Energy Laboratory, Golden, Colorado. 

4. B. H. West. 2015. “Higher Ethanol Blends for Improved Efficiency.” presented at the National 

Ethanol Conference, February 20, 2015, Grapevine, Texas. 

5. T. J. Theiss, R. McCormick, and M. Wang. 2015. “Increasing Biofuel Deployment through 

Renewable Super Premium.” presented at the Energy Future Coalition, March 24, 2015. 

6. R. McCormick, B. West, M. Wang, and T. Theiss. 2015. “Increasing Biofuel Deployment through 

Use of High Octane Fuels.” 25x’25 Webinar, June 18, 2015. 

Researchers at the National Transportation 

Research Center evaluate engine technologies with 

high-octane fuels using this modified Cadillac ATS. 

Groundbreaking ORNL Compatibility Work Used by Industry and 

Government 

Contact: Mike Kass, kassmd@ornl.gov, 865-946-1241 

A key ORNL compatibility study, Intermediate Ethanol Blends Infrastructure Materials Compatibility 

Study: Elastomers, Metals, and Sealants (ORNL/TM-2010/326, 2011), was cited in the July 15, 2015, 

Federal Register [80(135): 41566–41683; https://www.gpo.gov/fdsys/pkg/FR-2015-07-15/pdf/2015-

15914.pdf] under “Revising Underground Storage Tank Regulations—Revisions to Existing 

Requirements and New Requirements for Secondary Containment and Operator Training; Final Rule.” 

ORNL has been conducting fuel compatibility studies over the past 7 years to determine the compatibility 

of new fuel types (especially biofuels) with existing fuel storage and delivery system infrastructure 

components. These studies have focused on common elastomers, metals, plastics, and sealants. Properties 
2015 Annual Report Bioenergy Technologies R&D Highlights

ORNL Sustainable Transportation Program 13

used to assess compatibility were primarily volume and hardness change, but dynamic mechanical 

analysis was also performed on selected materials. The results show that oxygenated biofuels such as 

ethanol and butanol behave similarly. Both alcohol types show heightened solubility to elastomer and 

plastic seal and hose materials when added to gasoline at intermediate levels (15% to 50%). Bio-oil is also 

being evaluated as a distillate (i.e., diesel) substitute. Unlike the alcohols, it is not compatible with highperformance elastomers, such as fluorocarbons. It does, however, show good compatibility to lower-cost 

silicone rubber. 

ORNL compatibility work is of great interest to the petroleum and biofuels industries, where 

compatibility of biofuels with the existing infrastructure is a concern. Industry stakeholders such as the 

Petroleum Equipment Institute and the American Petroleum Institute have been consulted by ORNL 

researchers and provided input to the cited ethanol blends report (ORNL/TM-2010/326) and ongoing 

compatibility studies.

A key outcome of this ORNL work has been the establishment of a large database of compatibility 

properties that has been used by UL LLC (formerly Underwriters Laboratories Inc.) in developing new 

listing protocols for dispenser materials.

ORNL conducts studies to determine the 

compatibility of new fuel types with various 

materials using specially designed exposure 

chambers such as this one.

Publications, Presentations, and Patents

1. M. Kass, C. Janke, and T. Theiss, et al. 2015. “Compatibility Assessment of Plastic Infrastructure 

Materials with Test Fuels Representing E10 and iBu16.” SAE Int. J. Fuels Lubr. 8(1): 95–110; doi: 

10:4271/2015-01-0894.

2. M. Kass, C. Janke, and R. Connatser, et al. 2015. “Compatibility Assessment of Elastomeric 

Infrastructure Materials with Neat Diesel and a Diesel Blend Containing 20 Percent Fast Pyrolysis 

Bio-Oil.” SAE Int. J. Fuels Lubr. 8(1): 50–61; doi: 10.4271/2015-01-0888.

3. M. Kass, C. Janke, and R. Connatser, et al. 2015. “Compatibility Assessment of Plastic Infrastructure 

Materials with Neat Diesel and a Diesel Blend Containing 20 Percent Fast Pyrolysis Bio-Oil.” SAE 

Int. J. Fuels Lubr. 8(1): 80–94; doi: 10.4271/2015-01-0893.

4. M. Kass. 2015. “Compatibility Assessment of Elastomeric Infrastructure Materials with Neat Diesel 

and a Diesel Blend Containing 20 Percent Fast Pyrolysis Bio-Oil.” presented at the SAE 2015 World 

Congress, Detroit, Michigan, April 22, 2015.
Bioenergy Technologies R&D Highlights 2015 Annual Report

14 ORNL Sustainable Transportation Program

5. M. Kass. 2015. “Compatibility Assessment of Plastic Infrastructure Materials with Off-Highway 

Diesel and a Diesel Blend Containing 20 Percent Fast Pyrolysis Bio-Oil.” presented at the SAE 2015 

World Congress, Detroit, Michigan, April 22, 2015.

ORNL Develops International Fire Codes for the Bioenergy Industry

Contact: Erin Webb, webbeg@ornl.gov, 865-576-4814

Reducing the risk of biomass fires through science-based codes and standards was the focus of a 

multimember project led by ORNL in collaboration with the American Society of Agricultural and 

Biological Engineers; Idaho National Laboratory; and industry leaders Abengoa, DuPont, POET, Antares, 

and Genera Energy. 

Collectively known as the Biomass Industry Panel for Codes and Standards (BIPCS), the committee has 

actively influenced the development of international fire codes for the bioenergy industry. Fire risks, both 

real and perceived, have emerged as a potential barrier to the developing bioenergy industry. Feedstock 

volumes processed by commercial biorefineries have necessitated new standards that proactively address 

and ameliorate risks and promote improved safety strategies for the industry.

As part of the BIPCS effort, ORNL conducted experiments at UL LLC (formerly Underwriters 

Laboratories Inc.) to determine how factors such as feedstock type and bale size, shape, and spacing 

affect the speed at which a biomass fire can spread. Results showed, for instance, that round bales burn 

more quickly than square bales. 

These studies informed the development of future standards and codes on the safe handling and storage of 

biomass. The science-based codes and standards reduce risk to people and assets while improving the 

insurability of biomass facilities.

With support from the DOE Bioenergy Technologies Office, the BIPCS effort has accomplished five 

code changes to the International Building Code to date. The new code changes better reflect current 

knowledge of biomass properties and conventional and emerging storage, handling, and preprocessing 

technologies. Changes to the codes include clarifying that biomass is not a hazardous material, adding

bioenergy feedstocks to wood chapters, revising design of biomass storage piles, and adjusting the 

category for sprinkler design.

In addition to code changes, BIPCS also developed training and reference materials for engineers and 

code reviewers.

ORNL is working with UL to evaluate how feedstock type, bale shape, and bale spacing affect fire 

intensity under controlled conditions. (Images courtesy of UL.)
2015 Annual Report Bioenergy Technologies R&D Highlights

ORNL Sustainable Transportation Program 15

Publications, Presentations, and Patents

1. E. Webb. “Addressing Fire Risk in Biomass Handling and Storage.” presented at the 2015 ASABE 

Annual International Meeting, New Orleans, Louisiana, July 27, 2015.

ORNL-Led Consortium Leverages DOE Resources to Advance Biofuels 

Production; Impacts Feedstock Variations on Carbon Yield, 

Composition in Pyrolysis Oil

Contact: Stuart Daw, dawcs@ornl.gov, 865-946-1341

ORNL coordinated the Computational Pyrolysis Consortium (CPC), a joint collaboration among the 

National Renewable Energy Laboratory (NREL), Pacific Northwest National Laboratory, Argonne 

National Laboratory, Idaho National Laboratory, and several universities to improve the yield and 

efficiency of catalytic bio-oil upgrading for biofuels production. ORNL coordinated the CPC’s public 

website (http://cpcbiomass.org/), which shared models, data, and simulation results and facilitated 

collaboration with outside research groups. 

Among the results highlighted by the CPC were two low-order modeling methods developed by ORNL to 

facilitate improved estimation of the impact of different biomass feedstock species and preprocessing 

levels on the carbon yield and oxygen content of raw bio-oil used for catalytic upgrading. The first 

method was developed in collaboration with NREL and focused on particle-scale transport and kinetic 

effects that impact biomass conversion and oil yield during fast pyrolysis. The second method was 

developed in collaboration with one of the CPC industrial advisors and addressed how to predict the 

impact of pyrolysis mixing processes on overall conversion and yield. Taken together, the new modeling 

methods provided a direct computational link between the DOE Bioenergy Technologies Office biomass 

feedstock interface and the three targeted pathways for pyrolysis-derived biofuels. Open publications 

describing the modeling methods are listed on the CPC website. 

Preliminary analysis of catalytic upgrading of fast pyrolysis bio-oils indicated that this process has the 

potential to produce significant quantities of bio-derived diesel and gasoline fuels at costs approaching 

$3.00/gal. However, significant uncertainties remained concerning the costs and performance of the 

upgrading catalysts, the impact of biomass feedstock variations, and the ability of key reaction steps in the 

process to be scaled up to commercially relevant sizes. The computational facilities and expertise available 

across multiple national labs provided unique analytical and predictive capabilities harnessed to address 

remaining uncertainties, increasing the efficiency and value of ongoing pilot-scale demonstrations at the labs.

The level of lab-to-lab collaboration and coordination on this project set a new standard for minimizing 

duplication, maximizing efficient use of DOE lab resources, and leveraging capabilities and data across 

DOE programmatic boundaries. The DOE Bioenergy Technologies Office was the primary supporter of this 

work with high-performance computing time contributed by the Office of Science and computational tools 

developed with support from the DOE Fossil Energy Program and the DOE Vehicle Technologies Office.

Acting collectively, the CPC team identified four key areas in bio-oil technology for focusing its efforts: 

(1) feedstock impact, (2) reactor analysis and scale-up, (3) vapor-phase catalysis, and (4) liquid phase 

catalysis. 

In addition, a special team of industry advisors was established to review progress and ensure that the lab 

activities maintained their commercial relevance. The CPC provided a model for future multilab and 

multiprogram contributions to strategic DOE objectives, public information transfer, and direct 

collaboration among lab, industry, and university partners.
Bioenergy Technologies R&D Highlights 2015 Annual Report

16 ORNL Sustainable Transportation Program

Publications, Presentations, and Patents

1. T. R. Braun, A. Dutta, and J. Ziegler. 2014. “One Dimensional Steady-State Circulating FluidizedBed Reactor Model for Biomass Fast Pyrolysis.” Fuel 133: 253–262.

2. E. Ramirez, C. S. Daw, S. Pannala, J. Halow, C. E. A. Finney, and J. Galvin. 2014. “Computational 

Analysis of Biomass Particles in a Bubbling Bed.” presented at the 2014 AIChE Annual Meeting, 

Atlanta, Georgia, November 16–21, 2014.

3. G. Wiggins, C. S. Daw, and J. Halow. 2014. “Low-Order Modeling of Biomass Particle Mixing and 

Reaction in a Bubbling-Bed Fast Pyrolysis Reactor.” presented at the 2014 AIChE Annual Meeting, 

Atlanta, Georgia, November 16–21, 2014

4. J. L. Ziegler, S. Pannala, D. J. Robichaud, and M. R. Nimlos. 2015. “3D Multiphase Gas/Particle Flow 

Modeling for Reactor-Scale Biomass Conversion and Upgrading Simulations: Heat Transfer, Mixing, 

and Basic Deactivation Modeling in Fixed, Bubbling, and Fluidized Bed Reactors.” presented at the 

2014 NETL Workshop on Multiphase Flow Science, Morgantown, West Virginia, August 12–13, 2015.

Maps of instantaneous void fraction (inverse 

of catalyst fraction) and catalyst velocity in a 

lower riser section from 3D computational 

fluid dynamics simulations. 

Study Explains Underlying Process Behind Biofuel-to-Hydrocarbon 

Conversion Technology

Contact: Chaitanya Narula, narulack@ornl.gov, 865-574-8445

ORNL researchers have explained the mechanism behind a technology that converts bio-based ethanol 

into hydrocarbon blend-stocks for use as fossil fuel alternatives.

Scientists have experimented for decades with a class of catalysts known as zeolites that transform 

alcohols such as ethanol into higher-grade hydrocarbons. As ORNL researchers were developing a new 

type of zeolite-based conversion technology, they found that the underlying reaction unfolds in a different 

manner than previously thought.

It has been long thought that these types of reactions must first go from ethanol to ethylene, and then on 

to form longer chains. ORNL’s research showed that this energy-consuming intermediary step is not 
2015 Annual Report Bioenergy Technologies R&D Highlights

ORNL Sustainable Transportation Program 17

necessary for the conversion to happen. Instead, a “hydrocarbon pool” type mechanism allows the zeolite 

catalysts to directly produce longer hydrocarbon chains from the original alcohols.

ORNL researchers tracked the molecular transition in labeling experiments with deuterium, a hydrogen 

isotope, to confirm the hydrocarbon pool mechanism. 

The research, supported by DOE’s Bioenergy Technologies Office, has implications for the energy 

efficiency and cost of catalytic upgrading technologies proposed for use in biorefineries. Uncovering the 

mechanism behind the reaction helps support the potential economic viability of ORNL’s direct biofuel-tohydrocarbon conversion approach. The ORNL technology is a new pathway to biomass-derived renewable 

fuels, lowering greenhouse gas emissions, and decreasing US reliance on foreign sources of oil.

The ORNL-developed catalyst and conversion process were licensed in 2014 to Vertimass, a startup 

company based in Irvine, California. ORNL researchers are working with Vertimass through a separate 

DOE-funded project to scale the technology to the commercial level.

In addition, ORNL analysis in collaboration with the National Renewable Energy Laboratory shows the 

catalytic technology could be retrofitted into existing bio-alcohol refineries at various stages of ethanol 

purification. The direct conversion process produced minimal amounts of ethylene by-product, making the 

technology more cost-effective than previous approaches. The ORNL team’s lab-scale tests also indicated 

that the catalyst can operate at relatively low temperatures and pressures and can be regenerated under mild 

conditions, helping the technology withstand long periods of operation without significant degradation.

The technology uses an inexpensive zeolite catalyst to transform ethanol into hydrocarbon blend-stock. 

The resulting liquid is blended at various concentrations into gasoline, diesel, and jet fuels without 

negatively affecting engine performance. After being mixed with petroleum-derived fuels, the blend-stock 

does not require modifications to the existing distribution infrastructure. This technology is a pathway to 

overcoming the ethanol blend wall.

Publications, Presentations, and Patents

1. C. Narula, Z. Li, E. Casbeer, R. Geiger, M. Moses-Debusk, M. Keller, M. Buchanan, and B. Davison. 

2015. “Heterometallic Zeolite, InV-ZSM-5, Enables Efficient Conversion of Biomass Derived Ethanol 

to Renewable Hydrocarbons” Scientific Reports 5: 16039 [Highlighted in Science, 2015, 350, 1329].

Chaitanya Narula led analysis of an ORNL biofuel-tohydrocarbon conversion technology to explain the underlying 

process.

DOT R&D Highlights

ORNL Sustainable Transportation Program 19

DOT R&D Highlights

ORNL Completes Pilot Phase of System to Thwart Fuel Tax Evaders

Contact: Gary Capps, cappsgj@ornl.gov, 865-946-1285

Researchers at ORNL, working with partners from private industry, have completed the pilot phase of 

testing an integrated monitoring system that can track the movement of fuel tankers in real time and flag 

suspicious activity. The goal of the research was to provide a proof-of-concept system to identify illegal 

blending of nontaxable petrochemical products with taxable fuel products and cross-jurisdictional fuel tax 

evasion (FTE).

Revenues from motor fuel and other highway use taxes are the primary source of funding for the US 

transportation system, and ensuring that all of these taxes are collected, remitted, and credited to the 

Highway Trust Fund remains a priority for the DOT Federal Highway Administration (FHWA). While 

the exact figure is not known, more than $1 billion of revenue is estimated by FHWA to be lost each year 

to FTE. 

For federal tax purposes, the point of taxation for gasoline and diesel fuel is the point of removal from 

bulk storage at the terminal rack. About half of the states in the United States have the same point of 

taxation. For the remaining states, the point of taxation is at the wholesaler/distributor level or below. 

This has caused additional challenges in tracking untaxed fuel after it leaves bulk storage. Approaches to 

preventing FTE are time-consuming, along with attempts to discover and investigate evasions after the 

fact.

Using evidential reasoning techniques, ORNL researchers developed a supply-chain-based system that 

tracks fueling stops, loading, and unloading and provides near-real-time notification of any variation in 

standard delivery processes (e.g., a hatch or valve left open) from the tanker’s point of origin to its final 

destination.

Three fuel tankers were equipped with the systems for an 8-month pilot test beginning in late 2014. Data 

from the systems were processed daily. In 2015, data collections were completed. The pilot demonstration 

was performed for FHWA, state auditors, and enforcement personnel. More than 1,000 loads were 

monitored over the 8-month period. The system logged 374,453 miles and 7.5 million gallons of 

transported fuel.

The results of the pilot are expected to inform possible FHWA rulemaking on tracking and monitoring 

equipment. This system could also be used to track other kinds of goods as it is good for real-time 

tracking where suspicious or unusual activity needs to be flagged.

Overall, the system integrates sensor technology, wireless communications, vehicle tracking, and 

information analysis using a custom-developed sensor system, telematics, and sophisticated software. A 

user interface was developed to alert carriers to possible fuel theft, and a query tool was developed for use 

by state and federal auditors.
DOT R&D Highlights 2015 Annual Report

20 ORNL Sustainable Transportation Program

ORNL researchers developed a supply-chain-based system that tracks 

fueling stops, loading, and unloading, providing near-real-time 

notification of any variation in standard delivery processes from the 

tanker’s point of origin to its final destination.

Publications, Presentations, and Patents

None to report this period.

Private and Secure Connected Vehicle Communications Leads to 

Safer Transportation

Contact: Jason Carter, carterjm@ornl.gov, 865-574-1480

Connected vehicle technology has the potential to reduce accidents by 81% according to a study by the 

DOT. With the potential to save lives, save money, and even save fuel, connected vehicle technology is a 

“game changer” according to the ORNL Cyber and Information Security Research Group (CISR).

CISR has assisted DOT on connected vehicle research since 2012. ORNL’s work was cited in DOT’s 

2014 proposed rulemaking announcement regarding the potential regulation of vehicle-to-vehicle and 

vehicle-to-infrastructure connectivity.

The project was supported by the National Highway Transportation Safety Administration, the Federal 

Highway Administration, and the Intelligent Transportation Systems Joint Program Office.

In the near future, new vehicles will include devices to allow them to communicate (connect) with similar 

devices in other vehicles, sending basic safety messages with information such as vehicle position, 

direction, speed, braking status, and size. Similar information will be transmitted to stationary devices in 

the infrastructure, such as “smart” traffic lights.

Before this can happen, however, several challenges associated with the technology must be addressed, 

and ORNL has worked with DOT to be proactive in examining security and privacy.
2015 Annual Report DOT R&D Highlights

ORNL Sustainable Transportation Program 21

ORNL worked with DOT on the security side to research the means of ensuring the validity or 

trustworthiness of the messages exchanged between vehicles without revealing identifying information. 

Authenticating message broadcasts is a complex problem made more complicated by the size of the 

proposed deployment. After implementation, the credential management system will be the largest system 

of its kind, dwarfing a similar DOD system for information exchange.

ORNL’s role was to assess the feasibility of building this type of system with the trust/validation function 

delegated to the vehicles, including investigating the various technical solutions to make the approach 

feasible. The ORNL team delivered a concept of operations for the vehicle-based system. 

ORNL also researched how this technology can best preserve privacy while meeting the promise of 

improved safety and security. Privacy-preserving data publishing strategies were developed to remove or 

modify certain identifying characteristics within data streams and sets that will be used for future research 

and development, so the likelihood of the data being associated with a particular individual is reduced 

while the usefulness of the data is retained. The ORNL team developed an algorithm to successfully 

automate this process for vehicle trajectory data collected from pilot studies. They also examined how 

additional designed-in privacy techniques can be integrated into future operational connected vehicle 

technology.

Publications, Presentations, and Patents

1. J. M. Carter, N. Paul, and J. Zhang. 2015. “Analysis of Vehicle-Based Security Operations.” in 

Proceedings of the 24th International Technical Conference on the Enhanced Safety of Vehicles 

(ESV), June 8–11, 2015, Gothenburg, Sweden, Paper 15-0457 (PTS #55304); http://wwwesv.nhtsa.dot.gov/Proceedings/24/files/24ESV-000457.PDF.

ORNL assisted DOT with the development of a vehiclebased credential management system that can increase 

safety and security while maintaining privacy in vehicle-tovehicle and vehicle-to-infrastructure communications.

Image courtesy of Department of Transportation.
DOT R&D Highlights 2015 Annual Report

22 ORNL Sustainable Transportation Program

Wireless Roadside Inspection Project Improves Safety and Efficiency 

for Trucks and Buses

Contact: Gary J. Capps, cappsgj@ornl.gov, 865-946-1285

Safety inspections of commercial motor vehicles (CMVs) are critical to promoting safety on the 

roadways. Currently, safety inspectors in the United States perform about 3.4 million CMV inspections 

per year. The use of a wireless inspection method could dramatically increase the number of safety 

inspections without the need for additional enforcement personnel or new roadside infrastructure. Key 

data such as driver licensing and medical card, carrier and load information, and on-road hours are 

collected remotely through the Wireless Roadside Inspection (WRI) system developed by ORNL in 

partnership with industry. WRI allows this virtual inspection to occur without requiring the driver to stop. 

Routine inspections at weigh stations could supplement wireless inspections by further investigating 

trucks with questionable WRI data and trucks randomly selected for hands-on inspection. 

ORNL developed a system to collect and evaluate CMV safety data, working with a producer of onboard 

electronic recorder technology to develop software compatible with in-cab devices routinely used by the 

trucking industry.

WRI is similar to weigh station bypass in that it uses red/yellow/green light in the cab to indicate whether 

the driver can continue driving, pass through a station, or stop to see an inspector. The WRI system 

differs because it gathers safety and compliance data from all participants in addition to managing which 

trucks receive a hands-on inspection.

Overall, the WRI system is expected to increase the number of inspections and decrease the number of 

unsafe CMVs on the road. WRI speeds up the inspection process, enabling more inspections to occur, 

minimizing wait times, and reducing fleet costs. Since WRI is triggered when CMVs pass by designated 

geographic coordinates along the roadways, the system would make it far more unlikely that drivers could 

avoid inspection. 

The WRI team has completed the first two phases of the project: (1) evaluation of commercially available 

off-the-shelf or near-off-the-shelf technology to validate the wireless inspection concept; and (2) pilot 

testing, safety technology maturation, and back office system integration. The project is now entering 

Phase 3, the field operational test with a group of vehicles travelling a multiple-state instrumented 

corridor.

Publications, Presentations, and Patents

1. G. J. Capps, O. Franzese, H. Knee, R. Plate, and M. B. Lascurain. 2009. Wireless Roadside 

Inspection Proof of Concept Test Final Report. ORNL/TM-2008/128. Oak Ridge National 

Laboratory, Oak Ridge, Tennessee. 

2. G. J. Capps, 2013. “Wireless Roadside Inspection Field Test.” Tennessee Trucking Association 

Quarterly Meeting.
2015 Annual Report DOT R&D Highlights

ORNL Sustainable Transportation Program 23

The Wireless Roadside Inspection system remotely evaluates safety records 

of vehicles moving on the highways and flags trucks that are unsafe.

Fuel Cell Technologies R&D Highlights

ORNL Sustainable Transportation Program 25

Fuel Cell Technologies R&D Highlights

Analysis of Hydrogen Fuel Cell Onboard Storage Pressure

Contact: Zhenhong Lin, linz@ornl.gov, 865-946-1308

Fuel cell electric vehicles (FCEVs) are among the transportation options DOE is exploring to reduce 

greenhouse gas emissions and dependence on fossil fuels. Many issues have to be resolved before FCEVs 

can compete with traditional internal combustion engines or even battery electric vehicles. One of these 

relates to the onboard storage pressure of the hydrogen.

Higher hydrogen storage pressure allows more hydrogen to be stored on board, enabling a longer driving 

range between hydrogen refills, but the cost of the hydrogen supply infrastructure, and therefore the 

delivered cost of hydrogen, will be higher. Lower hydrogen storage pressure shortens the driving range 

and results in higher refueling frequency, and the range limitation cost can be higher. However, the lower 

capital cost of low-pressure stations (the infrastructure) may encourage investment in developing more 

stations, resulting in better refueling convenience for consumers and lower delivered hydrogen cost.

The purpose of this project is to develop an optimization model to identify the delivered pressure of 

hydrogen that best reflects the tradeoff among hydrogen cost, infrastructure capital cost requirements, 

onboard storage cost, driving range, refueling frequency, and refueling convenience in such a way as to 

maximize consumer acceptance of hydrogen vehicles and then analyze the results and recommend 

delivered hydrogen pressure as a function of technology cost, regional geography, hydrogen demand, 

driver types, and driving patterns. The model and findings can inform decisions affecting storage and 

market transformation barriers.

Based on the method developed for the hydrogen pressure analysis, a hydrogen optimal pressure (HOP) 

model with a user-friendly interface was implemented in Microsoft Excel. Model inputs are organized 

into three groups: Vehicle-Driver, Infrastructure, and Fleet-City. HOP model users can use the interface 

to examine in real time how the marginal cost curves shift up and down and how cost components of 350 

bar (about 5,000 lb/in.2

), 500 bar (about 7,252 lb/in.2), and 700 bar (about 10,000 lb/in.2) vary with 

changes of any input parameter.

Beta version of the interface for the HOP model. Left chart: marginal cost curves. 

Right chart: variations in cost components with changes of input parameters.
Fuel Cell Technologies R&D Highlights 2015 Annual Report

26 ORNL Sustainable Transportation Program

Over the 3 years of the project, the optimal pressure has varied due to different parameters and contexts. 

For example, FY 2013 results found 700 bar (about 10,000 lb/in.2

) to be more desirable in many regionstrategy scenarios. FY 2014 results demonstrated that 350 bar or 500 bar can be more competitive in 

reducing system cost in certain cluster strategy scenarios. FY 2015 results show strong preferences for 

700 bar over 350 bar or 500 bar because 700 bar is the only one among the three pressure levels to enable 

the greater than 300-mile range required for maximum ZEV (California Air Resources Board zero 

emission vehicle) credits. The ZEV credit, based on available credit trading information, is so valuable 

that the ZEV credit value becomes a dominating factor in the optimization, regardless of driver types. In 

addition, the longer driving range of 700-bar tanks (360 miles vs. 200–300 miles for 350- and 500-bar 

tanks) can be valuable to consumers with frequent long-distance and away-from-station-cluster trips. 

More research is needed on identifying the optimal pressure for early adopters of FCEVs, for maximizing 

FCEV market acceptance, and for standardization concerns. In 2016, the study will systematically 

investigate the optimal delivered hydrogen pressure with respect to how it is affected by parameters from 

the driver, vehicle, and hydrogen-refueling station categories. The interface for the HOP model will be 

further improved and will be used for analysis of the uncertainty of key parameters such as fuel economy, 

pressure incremental station cost, and driving intensity.

Publications, Presentations, and Patents

1. Z. Lin and C. Liu. 2015. “Analysis of Optimal Onboard Storage Pressure for Hydrogen Fuel Cell 

Vehicles.” presented at the 2015 DOE H2 Program and Vehicle Technologies Program Annual Merit 

Review and Peer Evaluation Meeting, Washington, DC, June 8–12, 2015.

Imaging and Microanalysis of Thin Ionomer Layers Using Advanced 

Microscopy Techniques

Contact: David A. Cullen, cullenda@ornl.gov, 865-356-3400

Many features of fuel cells make them attractive as power sources for vehicles, but currently they are too 

expensive to be viable commercial replacements for internal combustion engines. Among the strategies 

for making them more cost-competitive is improving catalyst performance to decrease the amount of the 

expensive platinum-group metals needed in the catalysts.

It is known that the percolating ionomer phase within a fuel cell electrode plays a critical role in mass 

transport and electrochemical kinetics within the catalyst layer. Distribution of the ionomer (thickness, 

morphology, contact with carbon and platinum) determines the electrochemical surface area and therefore 

the high-voltage and high-power performance of the fuel cell. Understanding ionomer dispersions within 

catalyst layers as a result of processing methods is thus important for achieving high-performing catalysts. 

ORNL staff and colleagues at the General Motors R&D Center; the University of Georgia; North 

Carolina State University; and CEA [the (French) Alternative Energies and Atomic Energy Commission], 

Grenoble, France, undertook a study using high-resolution scanning transmission electron microscope 

(STEM) imaging combined with compositional mapping to visualize and quantify the ionomer 

distributions within catalyst layers. To perform such studies, proper imaging protocols (temperature, 

voltage, and electron dose) were established to minimize beam damage during STEM.

To date, optimized conditions for imaging and spectroscopic analysis of perfluorosulfonic acid ionomer 

thin films within fuel cell electrodes have been investigated. Model systems comprising thin ionomer 

films of varying thickness applied to platinum surfaces were used to establish the proper STEM 

conditions for analysis. These conditions were then applied to quantitatively assess the through-thickness 

ionomer loadings of actual catalyst electrode layers prepared via different synthesis methods. 
2015 Annual Report Fuel Cell Technologies R&D Highlights

ORNL Sustainable Transportation Program 27

Additionally, high-resolution compositional mapping has been performed to show nonhomogeneous 

ionomer distributions within electrode structures.

STEM images acquired from a fuel cell electrode (a) before and (b) after acquisition of an energydispersive spectroscopy (EDS) image and (c) principal component analysis of the EDS image showing 

the different components in the image (catalyst support = blue, ionomer = green, platinum = red).

Publications, Presentations, and Patents

1. D. A. Cullen, R. Koestner, R. S. Kukreja, Z. Y. Liu, S. Minko, O.Trotsenko, A. Tokarev, L. Guetaz, 

H. M. Meyer, C. M. Parish, and K. L. More. 2014. “Imaging and Microanalysis of Thin Ionomer 

Layers by Scanning Transmission Electron Microscopy.” Journal of the Electrochemical Society 161: 

F111–F1117; doi: 10.1149/2.1091410jes.

Impact of Iridium-Ruthenium Oxygen Evolution Reaction Catalysts 

on PEMFC Electrode Catalysts

Contact: David A. Cullen, cullenda@ornl.gov, 865-356-3400

Polymer electrolyte membrane fuel cells (PEMFCs) have numerous applications, but they are particularly 

attractive for transportation applications because of their high power density and low weight. PEMFCs 

are more efficient than internal combustion engines, and their only emissions are water and heat, making 

them very environmentally friendly. However, because they typically use platinum group metal (PGM) 

catalysts, their costs are too high for market acceptability. Attempts to lower the PGM content and thus 

cost have run into durability problems, particularly under transient conditions such as start-up or 

shutdown (SU/SD)

ORNL is working with a team that includes 3M, Argonne National Laboratory, and Los Alamos National 

Laboratory to address these issues. 

In 2015, the team used advanced analytical electron microscopy techniques to study the effects of using 

oxygen evolution reaction (OER) catalysts to modify PEMFC anode and cathode catalysts to lower the 

overpotential for oxidation of water during transient conditions such as SU/SD. Keeping the electrode 

potential as close as possible to the thermodynamic potential of the OER leads to greater robustness and 

durability (i.e., increased catalyst stability and reduced degradation of the components of the fuel cell). 

Different loadings of ruthenium and iridium OER catalysts were incorporated onto 3M’s unique platinum 

nanostructured thin film (NSTF) catalyst. Aberration-corrected scanning transmission electron 

microscopy (STEM) was used to investigate the chemistry and structure of the iridium and ruthenium 

(a) (b) (c)
Fuel Cell Technologies R&D Highlights 2015 Annual Report

28 ORNL Sustainable Transportation Program

catalysts and the platinum NSTF (Pt-NSTF) catalysts before and after SU/SD testing. The results 

demonstrated that OER catalysts greatly improve the durability of Pt-NSTF catalysts by limiting platinum 

dissolution and that an OER catalyst loading of 2 μgcm-2 provided the optimal balance between 

performance, durability, and cost. Results of the atomic-scale investigations could provide new insights 

regarding fuel cell degradation mechanisms such as catalyst particle coalescence, platinum dissolution, 

and alloying.

Publications, Presentations, and Patents

1. D. A. Cullen, K. L. More, L. L. Atanasoska, and R. T. Atanasoski. 2014. “Impact of IrRu Oxygen 

Evolution Reaction Catalysts on Pt Nanostructured Thin Films under Start-up/Shutdown Cycling.” 

Journal of Power Sources 269: 671–681; doi: 10.1016/j.jpowsour.2014.06.153.

Bright field STEM images of (a) Pt-NSTF cathode layer 

in a membrane electrode assembly, (b) an individual PtNSTF whisker, (c) platinum surface without iridiumruthenium catalyst modified by the oxygen evolution 

reaction (OER), and (d) platinum surface with 

epitaxially grown Ir-Ru OER catalyst.

Pt

Pt

+

IrRu

(a)

(b) (c)

(d)

Membrane

Microporous layer

NSTF
2015 Annual Report Fuel Cell Technologies R&D Highlights

ORNL Sustainable Transportation Program 29

Melt-Spun Polyacrylonitrile for High-Strength Compressed Hydrogen 

Storage Systems

Contact: Felix L. Paulauskas, paulauskasfl@ornl.gov, 865-576-3785

High-strength carbon fiber (CF) enables the manufacture of durable, lightweight compressed hydrogen 

storage vessels for use in high-pressure storage and other clean energy applications. Unfortunately, 

current high-strength CF products are too expensive to meet DOE cost objectives—that is, too expensive 

for automotive applications. Melt-spun precursor has the potential to make a significant impact not only 

on the cost of the CFs used in hydrogen storage, but also on the cost of CFs used in the high-performance 

composites industry, including CF composites for vehicle body parts.

The technology typically employed for producing CF, known as “wet or solution spinning,” uses 

expensive, highly corrosive solvents and requires costly, time-consuming solvent recovery. Melt spinning 

avoids the significant costs entailed in handling and recovering the solvents used in solution spinning; it 

also eliminates a significant bottleneck in production caused by the time, space, and energy needed for the 

solvent recovery steps. Because of this, it is anticipated that the melt-spinning approach could save 25% 

of the costs associated with producing CF for high-pressure gas storage systems and that additional 

savings may be possible in combination with ORNL-developed advanced conversion approaches. It is 

also projected that the melt-spinning process would be more attractive for polyacrylonitrile (PAN) fiber 

production in the United States, possibly helping to revitalize some of the acrylic fiber business lost due 

to environmental concerns.

However, melt processing of a PAN precursor is a difficult issue because PAN degrades, even without 

main-chain scission or weight loss, and this essentially precludes melt processing with existing 

technology. ORNL and its partner, Virginia Tech, are addressing this in a strategy that builds on past 

patents and publications, ORNL’s decades-long CF R&D experience, and the capabilities of the Carbon 

Fiber Technology Facility. 

A major milestone was achieved in 2015 with demonstration of CF properties exceeding the DOE go/nogo point of 15 Msi modulus and 150 ksi strength. Properties meeting follow-on milestone levels up to 

25 Msi modulus and 250 ksi strength were also achieved. These properties were achieved with melt-spun 

PAN produced at Virginia Tech and using a conversion protocol developed by ORNL in previous work. 

Small tows spun at Virginia Tech were combined at ORNL to obtain a tow with an ample number of 

filaments (~100) to enable progressive tensioning during multiple oxidative stabilization steps and 

specific shrinkage management in low- and high-temperature carbonization. Currently this work is being 

scaled up to continuous processes that are projected to meet project technical and economic targets for 

producing significantly lower cost CF for high-pressure storage of hydrogen.

Publications, Presentations, and Patents

None to report this period.
Fuel Cell Technologies R&D Highlights 2015 Annual Report

30 ORNL Sustainable Transportation Program

Carbon Fiber Technology Facility pilot line being upgraded for 

automated operation and production of high-strength CF.
Vehicle Technologies R&D Highlights

ORNL Sustainable Transportation Program 31

Vehicle Technologies R&D Highlights

Analysis

MA3T Model Continues to Grow in Richness and Use

Contact: Zhenhong Lin, linz@ornl.gov, 865-946-1308

Understanding the diverse purchasing behaviors of individuals is key for designing efficient and effective 

policies for promoting advanced vehicle technologies. To address this need, ORNL developed Market 

Acceptance of Advanced Automotive Technologies (MA3

T), a market simulation model for the DOE 

Vehicle Technologies Program. Implemented using Microsoft Excel and cored with the nested 

multinomial logit model, MA3

T simulates market demand for advanced vehicle technologies by 

representing relevant attributes of technologies and consumer behavior such as technological learning by 

doing, range anxiety, access to recharging points, daily driving patterns, and willingness to accept 

technological innovation. Much remains to be learned about how consumers will evaluate novel vehicle 

technologies and how these technologies are likely to be accepted and used. Because of this, the approach 

taken in developing the MA3

T model was to create a framework for integrating data and behavioral 

models at an appropriate level of detail, whether all data were available or the behaviors were fully 

understood. MA3

T projections currently cover the period from 2005 to 2050 and capture the temporal 

interaction between market penetrations and product diversity and risk. 

Programmed with Visual Basic for Applications in Microsoft Excel, the model can run on computers with 

Microsoft Excel 2010 or newer versions. As more is learned about advanced vehicle technologies and 

consumer preferences toward them, the model is being updated and improved.

During FY 2015 the following updates/improvements were made.

• The representation of natural gas vehicles and state policies in MA3

T was improved.

• Technical documentation was updated.

• An updated version of MA3

T was released with the latest energy price and vehicle data.

In addition, a number of tasks to make MA3

T more useful and user friendly were completed, including 

establishing systematic calibration and validation processes and completing major structure upgrades and 

interface improvements.

MA3

T has been used in a wide variety of studies over the years, including, in 2015, the multilaboratory 

BaSce evaluation of the benefits of DOE Vehicle Technologies Office technologies and programs; the 

University of California, Davis, energy modeling project for the California Energy Commission; multiple 

ORNL studies; the International Institute for Applied Systems Analysis MESSAGE modeling framework; 

and the Tsinghua University Beijing, energy-vehicle market analysis for Honda. 

The MA3

T team started development of an MA3T “MiniTool” in 2015. Scheduled for release in 2016, the 

MiniTool will be a lighter, web-based version with a more user-friendly interface for both technical and 

nontechnical users. With the MiniTool, users will be able to efficiently check and download MA3

T 

outputs and learn about major functions of MA3

T online.

The current version of the model can be requested by contacting Zhenhong Lin (linz@ornl.gov).
Vehicle Technologies R&D Highlights 2015 Annual Report

32 ORNL Sustainable Transportation Program

Publications, Presentations, and Patents

1. E. Kontou, Y. Yin, and Z. Lin. 2015. “Socially Optimal Electric Driving Range of Plug-In Hybrid 

Electric Vehicles.” Transportation Research Part D: Transport and Environment 39: 114–125; doi: 

http://dx.doi.org/10.1016/j.trd.2015.07.002.

2. X. Wu, M. Aviquzzaman, and Z. Lin. 2015. “Analysis of Plug-In Hybrid Electric Vehicles’ Utility 

Factors using GPS-Based Longitudinal Travel Data.” Transportation Research Part C: Emerging 

Technologies 57: 1–12; doi: http://dx.doi.org/10.1016/j.trc.2015.05.008.

MA3T model framework.

ORNL Fuel Economy Information Project Accomplishments

Contact: Bo Saulsbury, saulsburyjw@ornl.gov, (865) 574-4694

The Fuel Economy Information (FEI) team developed and deployed “Selecting the Right Octane Fuel” on 

www.fueleconomy.gov. As part of creating these tips for the public, ORNL researchers evaluated the 

Ford Fiesta 1.0 turbocharged GDI with both regular and high-octane fuel. The research results provided a 

data source for the fueleconomy.gov octane tips and were published in a report along with companion 

results from a high-octane study supported by the DOE Bioenergy Technology Office. Researchers also 

presented the research data at the National Ethanol Conference.

FEI project team members worked with the University of Tennessee and the Virginia Department of 

Transportation to conduct and publish the study How Do Motorists’ Own Fuel Economy Estimates 

Compare with Official Government Ratings? A Statistical Analysis. The study used data from 

www.fueleconomy.gov “My MPG” database and was a follow-up to the 2011 study Predicting Individual 

On-Road Fuel Economy Using Simple Consumer and Vehicle Attributes.

The FEI project also released seasonal fuel economy tips to media contacts. “Cold Weather Fuel 

Economy Tips” was featured in several national and local media outlets, including The Detroit Free Press

and Bankrate.com, while “Save Money on Summer Driving” received coverage from USA Today, The 

Detroit Free Press, CBS News, and numerous local media outlets.
2015 Annual Report Vehicle Technologies R&D Highlights

ORNL Sustainable Transportation Program 33

Publications, Presentations, and Patents

1. B. West, 2015. “Higher Ethanol Blends for Improved Efficiency.” Presented at the National Ethanol 

Conference, Road to Higher Blends Panel. Grapevine, Texas. February 20.

2. J. Thomas, B. West, and S. Huff. 2015. Effects of High-Octane Ethanol Blends on Four Legacy FlexFuel Vehicles and a Turbocharged GDI Vehicle. ORNL/TM-2015/116. March.

My MPG on-road estimates vs. EPA label estimates of miles per gallon for all vehicle types.
Vehicle Technologies R&D Highlights 2015 Annual Report

34 ORNL Sustainable Transportation Program

Combustion, Engines, and Fuels

Advanced Control Strategies Key to Extending Dilution Limits in 

Light-Duty Vehicles

Contact: Brian Kaul, kaulbc@ornl.gov, 865-946-1299

ORNL is working with industry partners to improve light-duty vehicle fuel economy and to reduce 

emissions through control strategies that enable high-efficiency, high-dilution gasoline direct injection 

engine operation. An ancillary goal is to extend the exhaust gas recirculation (EGR) dilution limit for 

even greater gains.

Operating spark ignition engines with high levels of charge dilution through EGR achieves significant 

fuel efficiency gains and emissions improvements, but dilution is limited by cyclic variability. The closer 

you get to the theoretical limit of dilution (the so-called “edge of stability”), the greater the cyclic 

variability/instability, including misfires. This is especially true at the low engine loads typical of 

standard light-duty drive cycles. As a result, most engines are operated well away from the edge of 

stability to avoid these consequences, thus failing to achieve the full benefits of charge dilution.

ORNL researchers have determined that the cyclic variability encountered at the dilution limit is not 

random and that it is influenced by prior engine cycles. Using tools derived from chaos theory, the 

dynamics of systems using cooled EGR loops have been elucidated for the first time, and recurring 

patterns in cycle-to-cycle variations have been identified. This knowledge is being used to stabilize 

combustion near the dilution limit through control strategies based on the events of previous cycles. 

In related studies it was found that for high EGR levels, significant changes in the recirculated exhaust 

gas CO2 composition are carried through to the intake manifold and influence the events of future engine 

cycles. However, at lower EGR levels variations in composition are “damped out” before reaching the 

intake manifold and hence do not have the same impact on future cycles. Based on these findings, a 

strategy for predicting next-cycle effects has been devised and implemented on a test engine with good 

results at very high EGR levels, and alternate strategies were tested, with success, for moderate EGR 

levels. In addition, experiments have been conducted to gain further understanding of the impacts of other 

factors such as spark timing and spark restrike.

To achieve further improvement, more advanced, model-based control strategies will be pursued in the 

future, including collaboration in FY 2016 with an existing high-performance computing–based effort to 

develop control-oriented models (see “Using High-Performance Computing to Accelerate Engine 

Development” elsewhere in this report).
2015 Annual Report Vehicle Technologies R&D Highlights

ORNL Sustainable Transportation Program 35

Carbon dioxide concentration measurements for 20% exhaust gas recirculation.

Publications, Presentations, and Patents

1. T. Wallner, J. M. Sevik, Jr., R. Scarcelli, B. C. Kaul, and R. M. Wagner. 2015. “Effects of Ignition 

and Injection Perturbation Under Lean and Dilute GDI Engine Operation.” SAE Technical Paper 

2015-01-1871, 2015, doi:10.4271/2015-01-1871. 

2. C. S. Daw, C. E. A. Finney, B. C. Kaul, K. D. Edwards, and R. M. Wagner. 2015. “Characterizing 

Dilute Combustion Instabilities in a Multi-Cylinder Spark-Ignited Engine Using Symbolic Analysis.” 

Phil. Trans. R. Soc. A. 373(2034), doi: 10.1098/rsta.2014.0088. 

3. C. E. A. Finney, B. C. Kaul, C. S. Daw, R. M. Wagner, K. D. Edwards, and J. B. Green, Jr. 2015. “A 

Review of Deterministic Effects in Cyclic Variability of Internal Combustion Engines.” International 

J. of Engine Research 16(3): 366-378; doi: 10.1177/1468087415572033. 

4. B. C. Kaul, B. J. Lawler, C. E. A. Finney, M. L. Edwards, et al. 2014. “Effects of Data Quality 

Reduction on Feedback Metrics for Advanced Combustion Control.” SAE Technical Paper 2014-01-

2707, doi: 10.4271/2014-01-2707.

Cross-Cut Lean Exhaust Emissions Reduction Simulations Analysis 

and Coordination

Contact: C. Stuart Daw, dawcs@ornl.gov, 865-946-1341; Josh A. Pihl, pihlja@ornl.gov, 865-946-1524

As a result of advanced combustion research, in recent years there have been some amazing increases in 

internal combustion engine efficiencies and reductions in harmful greenhouse gas emissions. However, 

meeting the more stringent emissions regulations will require a combination of advanced emissions 

control devices and the computational tools needed to understand and predict their function. Recognizing 

this need, the DOE Advanced Engine Cross-Cut Team initiated the Cross-Cut Lean Exhaust Emissions 

Reduction Simulations (CLEERS) activity to support the development of improved computational tools 

and data for high efficiency engines and associated emissions control systems. DOE provides funding to 

ORNL to perform two complementary roles that support this goal: (1) administrative coordination of 
Vehicle Technologies R&D Highlights 2015 Annual Report

36 ORNL Sustainable Transportation Program

CLEERS collaborations among national laboratories, industry, and academia and (2) focused 

measurement, analysis, and modeling aimed at developing the strategies, data sets, and device parameters 

needed to address the most critical technological barriers faced by advanced emissions control systems. 

In its administrative role, ORNL serves as the primary interface with a planning committee composed of 

experts from national laboratories, industry, and academia; facilitates monthly technical teleconferences 

for an industry-academia focus group; organizes annual public workshops; conducts a biannual industry 

survey; and maintains a website for exchanging public data and information related to emissions controls 

(http://www.cleers.org). ORNL also acts as a clearinghouse for pre-proprietary information and reports, 

provides oral and written status reports to the Crosscut Team, and responds to public requests and 

inquiries. 

Measurement, analysis, and modeling activities are conducted in close collaboration with the Pacific 

Northwest National Laboratory and include identification of rate-controlling reaction mechanisms in 

catalytic devices under realistic operating conditions, development of modeling strategies that simulate 

the rate-controlling mechanisms with high computational efficiency, generation of benchmark data sets 

for model calibration and validation, and measurement of critical device parameters needed for model 

development. The results of these activities are disseminated through publications, presentations, and the 

CLEERS website. Research directions are guided by the Crosscut Team and by regular CLEERS industry 

participant priority surveys. ORNL’s CLEERS research activities have historically focused on approaches 

to NOX reduction in lean exhaust but have recently shifted to include low-temperature aftertreatment 

technologies such as passive adsorbers for NOX and hydrocarbons.

Noteworthy FY 2015 CLEERS activities included the following.

• Supporting the USDRIVE Advanced Combustion & Emissions Control (ACEC) Tech Team Low 

Temperature Aftertreatment Working Group in the development of new laboratory evaluation 

protocols that are accelerating the discovery of new catalysts.

• Conducting the biennial CLEERS Industry Priority Survey, collating the results, and issuing 

recommendations on the most pressing R&D needs to the Crosscut and ACEC Teams and DOE 

(http://www.cleers.org/reports/2015_CLEERS_Industry_Priorities%20Survey_Final_Report.pdf). 

This has helped improve the focus and industrial relevance of national laboratory emissions control 

projects supported by DOE. 

• Conducting detailed measurements of N2O formation during lean NOX trap regeneration. As a result 

of this research, the chemical pathways leading to N2O formation were identified, allowing 

development of more accurate simulation tools and improved operating strategies with the potential to 

significantly mitigate N2O emissions.

• Developing measurement and modeling strategies that accurately replicate the NH3 stored on 

commercial small-pore copper zeolite selective catalytic reduction (SCR) catalysts under dynamic 

driving conditions. The resulting model can now be incorporated into SCR device models to provide 

better predictions of NOx emissions control performance for these catalysts in proposed advanced 

vehicle powertrains, which will enable the development of system architectures and control strategies 

that meet increasingly stringent emissions regulations while reducing petroleum consumption. 
2015 Annual Report Vehicle Technologies R&D Highlights

ORNL Sustainable Transportation Program 37

NH3 storage properties of a commercial Cu-SSZ-13 urea selective catalytic reduction 

catalyst hydrothermally aged under 10% O2, 5% H2O, balance N2 for 4 h at 700°C 

(left), 4 h at 800°C (center), or 8 h at 800°C (right). Top and middle panels show 

measured (points) and modeled (dashed lines) steady state NH3 inventories as a 

function of temperature and (a) NH3 concentration under 0.2% O2, 5% H2O, balance 

N2 or (b) H2O concentration under 0.2% O2, 400 ppm NH3, balance N2. Bottom panels 

show estimated storage site densities after hydrothermal aging for site 1 and site 2 

based on the model fits shown in (a) and (b). All measurements were conducted on 

an automated flow reactor at a gas hourly space velocity of 30,000 h-1

.

Publications, Presentations, and Patents

1. D. Mráček, P. Kočí, M. Marek, J.-S. Choi, J. A. Pihl, and W. P. Partridge. 2015. “Dynamics of N2 and 

N2O Peaks During and After the Regeneration of Lean NOX Trap.” Applied Catalysis B: 

Environmental 166–167: 509–517.

2. Š. Bártová, D. Mráček, P. Kočí, M. Marek, and J.-S. Choi. 2015. “Ammonia Reactions with the 

Stored Oxygen in a Commercial Lean NOX Trap Catalyst.” Chemical Engineering Journal 278: 199–

206. 
Vehicle Technologies R&D Highlights 2015 Annual Report

38 ORNL Sustainable Transportation Program

3. D. Mráček, P. Kočí, J.-S. Choi, and W. P. Partridge. 2016. “New Operation Strategy for Driving the 

Selectivity of NOX Reduction to N2, NH3 or N2O During Lean/Rich Cycling of a Lean NOX Trap 

Catalyst.” Applied Catalysis B: Environmental 182: 109–114. 

4. J. A. Pihl and C. S. Daw. 2015. “Measuring the Impacts of Catalyst State on NH3 Adsorption in 

Copper Zeolite SCR Catalysts.” presented at the 2015 DOE Cross-Cut Lean/Low-Temperature 

Exhaust Emissions Reduction Simulations (CLEERS) Workshop, Dearborn, Michigan, April 27–29, 

2015.

5. J. A. Pihl and C. S. Daw. 2015. “NH3 Storage Isotherms: A Path Toward Better Models of NH3

Storage on Zeolite SCR Catalysts.” poster presented at the 24th North American Catalysis Society 

Meeting, Pittsburg, Pennsylvania, June 14–19, 2015. 

6. T. J. Toops. 2015. “The Measured and Proposed Chemistry of the Selective Catalytic Reduction of 

NOX.” invited plenary presentation at the 4th International Symposium on Modeling of Exhaust-Gas 

After-Treatment (MODEGAT IV), Bad Herrenalb, Germany, September 14, 2015.

Improving Vehicle Fuel Economy through Increasing Fuel Octane 

Ratings

Contact: Scott Sluder, sluders@ornl.gov, 865-946-1235

One of the ways to increase fuel efficiency while maintaining performance is to increase fuel octane, 

allowing higher compression ratios and greater thermal efficiency. Blending ethanol and other biofuels 

with conventional petroleum-based fuels can be an effective octane booster. Ethanol has a higher heat of 

vaporization (HoV) than gasoline, which may provide additional engine efficiency benefits. And it has the 

added advantage of increasing biofuel use and decreasing petroleum use. However, more data and better 

predictive tools are needed to adequately determine fuel property effects on combustion and engine 

efficiency optimization.

ORNL, with partners at other national labs, universities, and industry, is focusing on quantifying the fuel 

efficiency benefits of increasing the fuel research octane number (RON) by various methods as well as 

determining ancillary benefits from factors such as increasing the HoV. Currently fuels in the RON range 

of 90–100 are being investigated to characterize the amount of improvement that is possible using nearterm engine hardware and fuel octane levels. Later stages of this project will investigate more aggressive 

use of octane increases, which are likely to require improved engine boosting, compression ratio 

increases, and other hardware changes.

In 2015 ORNL researchers evaluated potential fuel economy differences for two different ethanol blends. 

E10 fuel (10% ethanol, 90% gasoline) was selected as the baseline at the suggestion of research partner 

Ford Motor Company. It was used to prepare an engine performance map using the Ford EcoBoost 1.6 L 

engine with the original pistons and a geometric compression ratio of 10.1 (Figure 1). An E30 fuel (30% 

ethanol, 70% gasoline) was used to examine the potential for increasing the compression ratio, replacing 

the original EcoBoost pistons with custom-manufactured pistons that produced a geometric compression 

ratio of about 13 (Figure 2). The impact of the fuel and the compression ratio on fuel economy was 

evaluated in vehicle system simulations using Autonomie. The results confirmed that use of high-octane 

fuels as enablers for increasing the compression ratio can produce significant improvements in vehicle 

fuel economy (4%–13%), but further research is needed to develop a robust estimate of the potential gains 

available through increasing fuel octane ratings. 

Researchers also analyzed three fuels with well-matched RONs and motor octane numbers (similar to 

RONs but determined under more rigorous driving conditions) to examine the potential of HoV to 
2015 Annual Report Vehicle Technologies R&D Highlights

ORNL Sustainable Transportation Program 39

provide additional antiknock benefits. The three fuels were formulated with ethanol, isobutanol, and 

toluene to provide differing HoV values. The results indicate that engine performance trends with fuel 

RON rating, which reinforces the concept that HoV antiknock effects can be viewed as a contributor to 

octane sensitivity. 

Further modeling improvements, along with expanding the vehicle system modeling effort to provide fuel 

economy for various powertrain configurations, are planned for FY 2016.

Publications, Presentations, and Patents

1. C. S. Sluder, J. P. Szybist, and B. C. Kaul. 2015. “Preliminary Investigation of Heat of Vaporization 

Effects in High-Octane Fuel Experiments at ORNL.” presented to the USDRIVE Advanced 

Combustion & Emissions Control Technical Team, July 16, 2015.

2. C. S. Sluder and D. A. Splitter. 2014. “Potential for Increasing Fuel Economy through Raising Octane 

Ratings.” presented to the staff of the DOE Vehicle Technologies Office and Biomass Energy 

Technology Office, US Department of Energy, December 15, 2014.

3. C. S. Sluder. 2015. “An Overview of High-Octane Fuel Projects at ORNL.” presented to the 

USDRIVE Fuels Working Group, February 18, 2015.

4. J. P. Szybist, S. Curran, C. S. Sluder, D. A. Splitter, A. B. Dempsey, and R. M. Wagner. 2015. 

“Gasoline-Like Fuel Effects on Advanced Combustion Regimes.” presented at the 2015 DOE Vehicle 

Technologies Office Annual Merit Review and Peer Evaluation Meeting, Washington, DC, June 11, 

2015.

Figure 1. The Ford EcoBoost 1.6 L engine installed 

at the ORNL National Transportation Research 

Center. 

Figure 2. The pistons used in the tests for (left to 

right) compression ratios of 10.1, 12, and 13.

Low-Temperature Emissions Control

Contact: Todd J. Toops, toopstj@ornl.gov, 865-946-1207

Advanced, higher-efficiency combustion engines have lower exhaust temperatures, which is problematic 

for emissions control as most catalysts work better in the 200°C to 350°C range. DOE’s low-temperature 

emissions control program has set a goal of a 90% reduction in pollutant emissions at temperatures at or 
Vehicle Technologies R&D Highlights 2015 Annual Report

40 ORNL Sustainable Transportation Program

below 150°C. ORNL researchers are focused on meeting this goal through nontraditional catalysts and 

materials in three areas: mixed metal oxides that are free of platinum-group metals (PGMs), PGM support 

modification for enhanced activity, and materials that trap hydrocarbons (HCs).

In 2015 work continued on ORNL’s copper-cerium-cobalt oxide (CCC) catalyst, a PGM-free ternary 

mixed oxide that has shown good activity for CO oxidation at low temperatures in a simulated exhaust 

stream and exceptional tolerance for C3H6 (propylene or propene) and other hydrocarbon species. In 

thermal-aging investigations, the CCC catalyst has shown stability up to 800°C.

In other investigations, the CCC catalyst was tested in combination with Pt/Al2O3, a catalyst known to 

have good HC activity, to find the lowest combined CO and HC catalyst operating temperatures through 

synergistic chemistry. A 50-50 mixture of the two was found to have high CO and C3H6 oxidation using 

half as much total platinum as Pt/Al2O3 alone (Figure 1). 

Efforts to modify PGM supports are focused on enhancing PGM catalyst activity/durability through 

modifications to the metal-oxide supports. Palladium on ZrO2 or ZrO2-modified supports has proven to be 

a stable catalyst. This year, working with palladium on ZrO2-modified silica, researchers were able to 

successfully synthesize a silica core with a ZrO2 shell with a more uniform ZrO2 coating than in the past, 

resulting in improved sulfur tolerance and HC oxidation. Initial results for hydrothermal aging are also 

good.

ORNL researchers also initiated research on capturing HCs during low temperature operation this past 

year. The method under investigation could be used to capture HCs under cold-start and other lowtemperature exhaust conditions for later release at higher temperatures, when the HCs could be oxidized 

by conventional catalysts. Zeolite Socony Mobil-5 (ZSM-5) and Beta zeolites were selected for 

evaluation based on industry feedback and on a literature survey, which indicated their thermal stability 

and thermodynamic affinity for HCs. Results indicate that both have the ability to adsorb C3H6, with Beta 

zeolites offering superior trapping capacity. Adding silver improves both trapping and desorption of C3H6

for both zeolites, with Beta zeolites again showing the most pronounced effects (Figure 2); this metal 

addition is essential for good trapping efficiency in the presence of water vapor.

Future work on all three approaches will focus on working with the challenges of the full exhaust mixture, 

aging, and sulfur resistance. 
2015 Annual Report Vehicle Technologies R&D Highlights

ORNL Sustainable Transportation Program 41

Figure 1. CO and C3H6 conversion of mixed bed (CCC+PA), split bed

(CCC PA), and deposited nanoparticle (Pt/CCC) catalysts compared with 

conversions on single catalyst beds (CCC, Pt/Al2O3).
Vehicle Technologies R&D Highlights 2015 Annual Report

42 ORNL Sustainable Transportation Program

Figure 2. Comparison of C3H6 concentration at the catalyst outlet during (a,b) adsorption as a 

function of time and (c,d) desorption of C3H6 as a function of temperature for (a,c) 

unexchanged and (b,d) silver-exchanged ZSM-5 and Beta zeolites.

Publications, Presentations, and Patents

1. A. J. Binder, T. J. Toops, R. R. Unocic, J. E. Parks II, and S. Dai. 2015. “Low Temperature CO 

Oxidation over a Ternary Oxide Catalyst with High Resistance to Hydrocarbon Inhibition.” Angew. 

Chem. Int. Ed. 54(45): 13263-13267; doi: 10.1002/ange.201506093.

2. M. Kim, E. A. Kyriakidou, J. Choi, T. J. Toops, A. J. Binder, C. Thomas, J. E Parks II, V. Schwartz, 

J. Chen, and D. K. Hensley. 2016. “Enhancing Low-Temperature Activity and Durability of Pd-based 

Diesel Oxidation Catalysts Using ZrO2 Supports.” Applied Catalysis B: Environmental 187: 181–194; 

doi: 10.1016/j.apcatb.2016.01.023.

3. A. P. Wong, E. A. Kyriakidou, T. J. Toops, and J. R. Regalbuto. 2016. “The Catalytic Behavior of PtPd Bimetallic Catalysts for Use as Diesel Oxidation Catalysts.” Catalysis Today 267: 145-156; 

doi:10.1016/j.cattod.2016.02.011.

4. A. J. Binder, T. J. Toops, R. R. Unocic, J. E. Parks II, and S. Dai. 2015. “Inhibition-Resistant Ternary 

Oxide Catalyst for Low Temperature CO Oxidation in Automotive Exhaust.” presented at the 14th 

Annual Fall Symposium of the Southeastern Catalysis Society, Clemson, South Carolina, September 

27–28, 2015.

5. E A. Kyriakidou, J. Choi, M. Kim, T. J. Toops, and J. E. Parks II. 2015. “A Comparative Study of 

ZSM-5 and Beta-Zeolites for Hydrocarbon Trap Applications under ‘Cold-Start’ Condition.” 
2015 Annual Report Vehicle Technologies R&D Highlights

ORNL Sustainable Transportation Program 43

presented at the 14th Annual Fall Symposium of the Southeastern Catalysis Society, Clemson, South 

Carolina, September 27–28, 2015.

6. T. J. Toops. 2015. “Approaches to the Challenges of Treating Emissions at Low Temperatures.” 

presented at the Karlsruhe Institute of Technology, Karlsruhe, Germany, September 17, 2015 

(invited).

Neutron Imaging of Advanced Vehicle Technologies

Contact: Todd J. Toops, toopstj@ornl.gov, 865-946-1207

Neutrons can penetrate many commonly used metals, can be used to image many light elements such as 

hydrogen, and are highly sensitive to water and hydrocarbons (fuels), which makes neutron imaging well 

suited to probe engine parts, fluids, and oil and related residues. Researchers at ORNL are developing 

high-fidelity nondestructive, noninvasive neutron imaging techniques to improve understanding of 

advanced vehicle technologies using the unique capabilities of the ORNL High Flux Isotope Reactor and 

Spallation Neutron Source. To improve upon the results, internal ORNL funds have been invested in the 

hardware and experimental effort, which will enable dynamic neutron imaging of advanced vehicle 

technologies, improved resolution, and stroboscopic imaging capability. Once fully developed, the 

techniques will be used to aid improved design and control of complex advanced combustion systems and 

to guide model validation and input.

Initial efforts have been focused on two important components of advanced vehicle systems, in-cylinder 

fuel injectors and particulate filters (PFs). 

In-cylinder fuel injectors are among the innovations bringing internal combustion engines into the 21st 

century; however, they are not without their drawbacks, including fouling or deposit formation, which can 

affect engine performance. During 2015, the ability of neutron imaging to measure fuel injector fouling 

has been fully demonstrated in work with research partner Continental Automotive. Use of this technique 

to measure carbonaceous deposits without cutting the injectors open will be important in the future for 

understanding fouling under a variety of conditions. Neutron imaging of fuel injection in a dynamic 

capacity was also demonstrated, with the technique proving capable of visualizing the rate of evaporation 

in the internal injector sac as a function of injector or chamber conditions. In the future, ORNL 

researchers will be teaming with injector suppliers on broader studies.

PFs are key components of the emissions control systems of modern diesel engines, and possibly gasoline 

engines in the future, yet there remain significant questions about the basic behavior of the filters. 

Regeneration processes, specifically, are not well understood, including how ash (nonregenerable metaloxide-based particulate) fills a PF and interacts with the wall. Neutron imaging of PFs in collaboration 

with the Massachusetts Institute of Technology (MIT) is helping to clarify some of these issues. During 

2015 ash profiles and densities for different soot regeneration strategies were identified, revealing a series 

of deposits that greatly compromise the full functionality of PFs. Work with MIT will continue, and if 

possible, the technique will be used to provide detailed understanding of soot and ash distribution.

Publications, Presentations, and Patents

1. T. J. Toops, J. A. Pihl, C. E. A. Finney, J. Gregor, and H. Bilheux. 2015. “Progression of Soot Cake 

Layer Properties during the Systematic Regeneration of Diesel Particulate Filters Measured with 

Neutron Tomography.” Emission Control Science and Technology 1(1): 24–31, doi: 10.1007/s40825-

014-0008-1.
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44 ORNL Sustainable Transportation Program

2. T. J. Toops, E. Nafziger, C. E. A. Finney,H. Bilheux, and J. Bilheux. 2015. “Effect of Regeneration 

Strategy on the Ash Distribution and Packing Density Measured with Neutron and X-Ray

Radiography.” 2015 SAE World Congress, Detroit, Michigan, April 23, 2015.

3. T. J. Toops, E. Nafziger, C. E. A. Finney, H. Bilheux, and J. Bilheux. 2015. “Effect of Regeneration 

Strategy on the Ash Distribution and Packing Density Measured with Neutron and X-Ray 

Radiography.” Massachusetts Institute of Technology Consortium to Optimize Lubricant and Diesel 

Engines for Robust Aftertreatment Systems, Spring Review Meeting, Cambridge, Massachusetts, 

May 13, 2015. 

4. H. Z. Bilheux, C. E. A. Finney, A. E. Pawlowski, D. A. Splitter, T. J. Toops, E. J. Nafziger, and L. J. 

Santodonato. 2015. “Neutron Imaging of Advanced Transportation Technologies.” presented at the 

Workshop on Needs and Requirements for Future Research Reactors, Oak Ridge National 

Laboratory, May 12, 2015.

5. T. J. Toops, C. E. A. Finney, E. J. Nafziger, D. Splitter, M. DeBusk, and A. Pawlowski. 2015. 

“Neutron Imaging of Advanced Transportation Technologies.” presented at the US Department of 

Energy Vehicle Technologies Office 2015 Annual Merit Review and Peer Evaluation Meeting, 

Washington, DC, June 10, 2015. 

6. T. J. Toops, D. A. Splitter, L. J. Santodonato, A. E. Pawlowski, E. J. Nafziger, C. E. A. Finney, and 

H. Z. Bilheux, “Dynamic Neutron Imaging of GDI-Based Fuel Injection.” presented at the 

US Department of Energy Vehicle Technologies Office Advanced Engine Combustion Meeting, 

Southfield, Michigan, August 16, 2015. 

Time-stamped images show composite injection event and illustrate fuel in sac long after pintle closes.
2015 Annual Report Vehicle Technologies R&D Highlights

ORNL Sustainable Transportation Program 45

ORNL Investigates How New Fuels and Lubricants Affect Emission 

Systems

Contact: Todd J. Toops, toopstj@ornl.gov, 865-946-1207

ORNL researchers are investigating how new fuel blends and lubricants affect vehicle emission control 

systems. The aim is to determine the potential of the new chemistries, both to increase engine 

performance and to degrade exhaust system performance. 

Experiments with engines running lean fuel mixtures (high ratios of air to fuel) showed that fuel blends 

containing ethanol and isobutanol (iBuOH) are readily controlled by selective catalytic reduction using a 

relatively inexpensive silver-based catalyst. The tests used E100, E85, and E50 ethanol-gasoline blends 

and pure iBuOH and iBuOH-gasoline blends. An important finding was that higher ethanol content in the 

fuel significantly reduced the amount of hydrocarbons that bypass the emission control system while 

maintaining the NOx reduction activity.

A series of measurements of particulate matter (PM) emissions focused on analyzing the performance of 

biofuels during start-stop conditions (a point in the cycle when PM emissions tend to be higher). Three 

fuels—E0 (conventional gasoline), E30, and an isobutanol blend (iBu24)—were evaluated in a 2014 

Chevrolet 2.4 L gasoline direct injection engine. The results showed that E30 had the lowest level of PM 

emissions and was unaffected by start-stop operation. The iBu24 mixture was the only one that showed 

any adverse effect on PM under start-stop conditions. The tests also showed that the PM generated by the 

E30 blend reacts more easily with the catalyst than the PM generated by E0.

0

1

2

3

4

5

Start-Stop No Start-Stop

E0

E30

IBu24

Tier 2 PM limit is 10 mg/mile 

FTP composite PM emissions for E0, E30, and iBu24 under startstop and conventional mode (no start-stop) operation.

New lubricants are being developed that reduce friction inside engines, improving efficiency and reducing 

wear. Ionic liquid (IL) lubricant additives, in particular, have been demonstrated to improve fuel 

economy. It is important to determine whether they are compatible with currently used emissions control 

systems. The ORNL team evaluated DEHP (diethylhexyl phthalate) phosphate, an IL that is an oilmiscible phosphorus compound, to compare its effects on a three-way catalyst (TWC) with those of the 

industry standard additive, ZDDP (zinc dialkyldithiophosphate). Results from a series of tests with TWCs 
Vehicle Technologies R&D Highlights 2015 Annual Report

46 ORNL Sustainable Transportation Program

aged under different scenarios showed that the IL additive had a somewhat less adverse impact on the 

catalyst than did ZDDP.

ORNL researchers, in collaboration with the engine maker Cummins, the National Renewable Energy 

Laboratory, and the Manufacturers of Emission Controls Association, studied the impacts of sodium 

impurities in biodiesel on a heavy-duty truck emission control system. A full exhaust system was 

operated on a test rig for more than 1,000 h using a fuel blend of 80% gasoline and 20% biodiesel doped 

with 14 ppm of sodium. A series of sophisticated characterization techniques showed that the primary 

effect of the sodium on the exhaust system was increased ash in the diesel particulate filter, but the 

catalysts were not directly impacted by sodium. The data from this study will be useful in determining 

appropriate sodium standards for biodiesel fuels.

Publications, Presentations, and Patents

1. V. Y. Prikhodko, J. A. Pihl, T. J. Toops, J. Thomas, J. E. Parks II, and B. West. 2015. “Selective 

Catalytic Reduction of Oxides of Nitrogen with Ethanol/Gasoline Blends over a Silver/Alumina 

Catalyst on Lean Gasoline Engine.” SAE Technical Paper Series 2015-01-1008, SAE International, 

Warrendale, Pennsylvania.

2. D. W. Brookshear, J. Nam, K. Nguyen, T. J. Toops, and A. Binder. 2015. “NOx Performance of CuChabazite SCR Catalysts under Severe Sulfur Poisoning from Marine Diesel Engine’s Fuels.” 

Catalysis Today 258: 359–366.

3. P. Ye, C.-X. Sun, M. Lapuerta, J. Agudelo, R. Vander Wal, A. L. Boehman, T. J. Toops, and C. S. 

Daw. 2016. “Impact of Rail Pressure and Biodiesel Fueling on the Particulate Morphology and Soot 

Nanostructures from a Common-Rail Turbocharged DI Diesel Engine.” International Journal of 

Engine Research 17(2): 193–208.

4. J. M. Storey et al. 2014. “Investigation of the Potential Impact of Lubricant Contribution to the 

Formation of Particulate Matter with Reactivity Controlled Compression Ignition on Light-Duty 

Diesel Engines.” Emission Control Science and Technology 1(1): 64.

5. M. Lance and T. J. Toops. 2014. “Impact of Metal Impurities on Catalyst Durability.” invited 

presentation at 2014 Biodiesel Technical Workshop, Kansas City, Missouri, October 28–29, 2014.

6. D. W. Brookshear, J. A. Pihl, B. H. West, T. J. Toops, and V. Prikhodko. 2015. “The Selective 

Catalytic Reduction of NOx over Ag/Al2O3 with Isobutanol as the Reductant.” submitted to Catalysis 

Today.

Stretching Internal Combustion Engine Efficiency with New 

Combustion Regimes

Contact: James Szybist, szybistjp@ornl.gov, 865-946-1514

In continuing work on a multiyear project to increase internal combustion engine (ICE) efficiency, ORNL 

researchers and partners from industry, academia, and other national labs have demonstrated a fuel 

consumption benefit of more than 9% (approaching diesel efficiency) using an ORNL-developed 

operation strategy. That result fell below the researchers’ expectations because the thermochemical 

recuperation (TCR) fuel reforming had a lower fuel conversion rate than expected; however, further 

efficiency improvements are anticipated as the researchers refine the operating strategy to achieve higher 

reforming fuel conversion. 
2015 Annual Report Vehicle Technologies R&D Highlights

ORNL Sustainable Transportation Program 47

The thermal efficiency of ICEs can be improved with exhaust gas recirculation (EGR). The problem is 

that combustion instabilities are induced above a certain level of EGR dilution, limiting efficiency 

improvements. However, the dilution limit can be extended for additional efficiency improvements with 

the use of high flame speed/low ignition energy components such as H2, which stabilize dilute 

combustion.

In the current project, ORNL researchers are exploring two pathways to TCR to support high EGR 

dilution: (1) a noncatalytic in-cylinder reforming approach (Figure 1) that thermally reforms the fuel in a 

hot, oxygen-deficient negative valve overlap portion of an engine cycle and (2) EGR loop reforming, a 

strategy that relies on a catalyst (in this case rhodium on alumina) to reform the fuel in an oxygendeficient EGR stream (Figure 2). Both approaches use waste exhaust heat to drive endothermic reforming 

reactions to produce a mixed reformate and EGR stream that is rich in H2 and CO. The reformate can then 

be used to extend the EGR dilution limit of spark-ignited combustion for a more thermodynamically 

favorable engine cycle.

Parametric studies of both processes were conducted to further characterize the reforming process, H2

generation, and engine efficiency. For the noncatalytic in-cylinder reforming process, engine efficiency 

improvements were observed that resulted in a decrease in fuel consumption of more than 9% relative to 

the baseline case. The efficiency improvements were attributable to a cylinder deactivation effect in 

conjunction with cooled external EGR rather than TCR. Analysis showed that the fuel conversion was 

lower than anticipated because of relatively cool in-cylinder temperatures, a result of high heat losses. 

Continuing experiments in FY 2016 will focus on decreasing heat losses to increase fuel conversion with 

less oxygen, which reduces the thermodynamic efficiency of the process.

For the EGR loop reforming process with the rhodium-based catalyst, it was concluded that the exhaust 

temperatures with EGR are insufficient to reform the fuel in the absence of oxygen (steam reforming). 

Thermodynamic investigations found that TCR may still be possible with some amount of oxygen 

present. The conditions where a high reforming efficiency is observed are not necessarily the conditions 

leading to the highest H2 production. Ultimately, the thermodynamic benefits will need to be assessed in 

an engine, an activity that will be pursued in FY 2016.

The project, which is funded by the DOE Vehicle Technologies Office, grew out of a colloquium on 

engine efficiency held in 2010 [1] and focuses on high risk, high reward technologies that could have a 

major impact on ICEs for the foreseeable future.
Vehicle Technologies R&D Highlights 2015 Annual Report

48 ORNL Sustainable Transportation Program

Figure 1. In-cylinder reforming process. Figure 2. EGR loop reforming process.

References

1. C. S. Daw, R. L. Graves, R. M. Wagner, and J. A. Caton. 2010. Report on the Transportation 

Combustion Engine Efficiency Colloquium Held at USCAR, March 3–4, 2010, ORNL/TM-2010/265, 

Oak Ridge National Laboratory, Oak Ridge, Tennessee.

Publications, Presentations, and Patents

1. J. P. Szybist and D. A. Splitter. 2015. “In-Cylinder Fuel Reforming to Support High EGR Dilution in 

High Efficiency SI Engines.” presented at the IEA Task Leaders Meeting on Combustion, St. 

Andrews, Scotland, August 2015. 

2. I. Ekoto, B. Peterson, J. Szybist, and W. Northrop. 2015. “Analysis of Thermal and Chemical Effects 

on Negative Valve Overlap Period Energy Recovery for Low-Temperature Gasoline Combustion.” 

SAE International Journal of Engines 8(5): 2227–2239, doi: 10.4271/2015-24-2451.

3. J. P. Szybist. 2015. “Update of ORNL In-Cylinder Reforming Investigation.” presented at the AEC 

Program Review Meeting, Sandia National Laboratories, February 2015.

4. C. S. Daw, J. P. Szybist, J. A. Pihl, D. A. Splitter, and G. Fisher. 2015 “Stretch Efficiency for 

Combustion Engines: Exploiting New Combustion Regimes.” presented at the 2015 DOE Vehicle 

Technologies Office Annual Merit Review and Peer Evaluation Meeting, Washington, DC, June 18, 

2015.
2015 Annual Report Vehicle Technologies R&D Highlights

ORNL Sustainable Transportation Program 49

Using Advanced Fuels in Advanced Combustion Regimes

Contact: Scott Curran, curransj@ornl.gov, 865-946-1522; James Szybist, szybistjp@ornl.gov, 865-946-

1514

Two related projects investigated the performance of several advanced fuels in different advanced 

combustion regimes. The advanced compression ignition (ACI) project investigated the potential for

coevolution of these emerging combustion technologies and biofuels to reduce petroleum consumption in 

future engines. The spark ignition (SI) project analyzed methods of increasing the efficiency of gasolinelike fuels under both advanced and conventional combustion regimes.

Identifying pathways to improved engine efficiency requires understanding the thermodynamics of 

internal combustion engines. Many renewable and advanced fuels have unique properties that could 

increase fuel efficiency in both ACI and SI modes. These two projects are exploring which properties of 

renewable fuels can enable higher-efficiency operation.

The 2015 objectives were to

• demonstrate the potential of biofuels to obtain efficiency targets with reactivity-controlled 

compression ignition (RCCI), 

• compare dual-fuel RCCI and single-fuel gasoline compression ignition (GCI), and 

• determine the extent and causes of fuel-specific differences in exhaust gas recirculation (EGR) 

dilution tolerance at light-load engine conditions in an SI engine.

The ACI project met the 2015 technical target for demonstrating fuel effects of 36% brake thermal 

efficiency (BTE) at 2,000 rpm and 20% peak load. The ACI project compared the efficiency, load 

expansion, and controllability for RCCI with conventional fuels and GCI with fuels spanning a wide 

range of research octane numbers (RONs). The SI project showed that EGR tolerance limits can be 

attributed to stochastic cycle-to-cycle instabilities and fuels with faster flame speeds are more resilient to 

stochastic turbulence and thus able to tolerate more dilution.

ACI Research

The ACI project used a modified modern General Motors 1.9 L multicylinder diesel engine. The effects 

of fuel properties on both single- and dual-fuel combustion strategies on the same engine platform were 

considered. The 2,000 RPM, 20% peak load conditions were similar to those common in real-world 

driving. The 36% BTE, achieved using biodiesel and gasoline as the high- and low-reactivity fuels, 

respectively, is a 6% improvement over the conventional diesel combustion baseline diesel fuel 

(Figure 1).

In addition, GCI experiments on fuel effects were done using gasoline-range fuels supplied by Chevron 

Energy Technologies in partial fuel stratification (PFS) and heavy fuel stratification (HFS) modes. They 

investigated the effects of RONs ranging from 40 to 87 on both PFS and HFS low-temperature GCI 

modes. Each of seven fuels was run at 2,000 rpm, 4.0 bar brake mean effective pressure in HFS mode 

sweeping the amount of EGR and other key parameters.
Vehicle Technologies R&D Highlights 2015 Annual Report

50 ORNL Sustainable Transportation Program

Figure 1. Comparison of FY 2015 advanced compression ignition milestone 

accomplishment with other combustion technologies.

SI Research

The SI project used a modern direct-injection single-cylinder research SI engine to examine six model 

fuel blends at a constant RON of 95 using n-heptane, iso-octane, toluene, and ethanol (Figure 2). Laminar 

flame speeds for the mixtures spanned a range of about 6 cm/s. The results illustrated that fuels with 

increased flame speeds increase EGR tolerance. Fuel blends with the highest ethanol content were the 

most tolerant of dilution. The fuel-specific differences in dilution tolerance allowed for a 50% relative 

increase in EGR (4% absolute difference) at a constant coefficient of variation of indicated mean effective 

pressure of 3%.

Both of these projects are being brought into the DOE Co-Optimization of Fuels & Engines initiative in 

FY 2016. Fuel effects on advanced combustion continue to be explored with a verity of advanced and 

renewable fuels. The high-efficiency SI project will continue to contribute to the understanding of fuel 

effects on dilution tolerance and is ready to test candidate fuels from the co-optimization initiative. Both 

of these projects will collaborate with other internal and external projects within the larger DOE initiative. 
2015 Annual Report Vehicle Technologies R&D Highlights

ORNL Sustainable Transportation Program 51

Figure 2. Compositions of the six surrogate blends used to investigate 

exhaust gas recirculation dilution tolerance in spark ignition engines, 

each with a research octane number of 95.

Publications, Presentations, and Patents

1. B. Dempsey, S. J. Curran, R. M. Wagner, and W. Cannella. 2014. “Effect of Premixed Fuel 

Preparation for Partially Premixed Combustion with a Low Octane Gasoline on a Light-Duty 

Multicylinder Compression Ignition Engine.” J. Engineering for Gas Turbines and Power 137(11): 

111506.

2. S. J. Curran, A. Gao, and R. M. Wagner. 2015. “Reactivity-Controlled Compression Ignition Drive 

Cycle Emissions and Fuel Economy Estimations using Vehicle System Simulations.” Int. J. Engine 

Research 16, 1014–1024.

3. D. A. Splitter. R. M. Wagner, A. B. Dempsey, and S. J. Curran. 2015. “The Landscape of GCI 

Combustion—Fuel Properties and Stratification.” presented at the SAE 2015 Gasoline Compression 

Ignition Engine Symposium, Capri, Italy, September 17, 2015 (invited).

4. S. J. Curran, R. M. Wagner, and A. B. Dempsey. 2015. “Next-Generation Compression Ignition 

Engines and Future Fuel Opportunities.” presented at the 2015 SAE/JSAE Powertrain Fuels and 

Lubricants International Meeting, Kyoto, Japan, September 1–4, 2015 (invited).

5. R. M. Wagner, A. B. Dempsey, and S. J. Curran, “Directions in High Efficiency Engine Research and 

Future Fuel Opportunities.” presented at the 13th International Conference on Engines for Vehicles, 

Port Jefferson, New York, June 22, 2015 (invited).

6. D. A. Splitter and J. P. Szybist. 2015. “Fuel Effects and EGR Dilution Limits with SI Combustion.” 

presented at the Advanced Engine Combustion Program Review, Livermore, California, February 

2015. 
Vehicle Technologies R&D Highlights 2015 Annual Report

52 ORNL Sustainable Transportation Program

Using High-Performance Computing to Accelerate Engine 

Development

Contact: K. Dean Edwards, edwardskd@ornl.gov, 865-946-1213

ORNL is partnering with Ford Motor Company, Convergent Science, General Motors, General Electric, 

and other industry stakeholders to use DOE high-performance computing (HPC) resources (Figure 1) to 

accelerate design and development of advanced engines to meet future emissions and fuel economy goals. 

Specific projects evolve in response to DOE and stakeholder priorities and as tasks and projects are 

completed.

Current efforts are focused on understanding and 

controlling cycle-to-cycle variability in highly 

dilute and dual-fuel combustion applications and 

optimizing gasoline direct injection (GDI) fuel 

injector design. 

Combustion instability is a potential barrier to 

realizing the full benefits of many advanced 

combustion strategies, such as dilute and dualfuel (natural gas–diesel) combustion, which 

offer advantages in terms of engine efficiency, 

cost, and pollutant emission reductions. This 

past year, ORNL researchers used highly 

parallelized engine simulations on ORNL’s 

Titan supercomputer to better understand the 

stochastic and deterministic processes driving 

cyclic variability in dilute combustion. Results 

from the simulations were used to generate metamodels to study serial combustion events and the 

parameters that promote combustion instability. Final analysis of the simulation results from this effort 

will continue in FY 2016. The approach, which uses uncertainty quantification and sparse-grids sampling, 

was also applied to the study of instabilities in dual-fuel locomotive applications. The extent of cyclic 

variability observed for dual-fuel operation was not fully captured by the initial round of simulations, 

which focused on variability with a limited number of inputs. An expanded study is planned for FY 2016 

to examine the impact of additional stochastic inputs and deterministic feedbacks.

GDI, a type of fuel injection, is used in modern engines for improved fuel efficiency and reduced 

emissions. Injector design is currently a lengthy, labor-intensive process typically involving numerous 

hardware iterations. GDI injector design was selected for this project because of the potential to automate 

the design process, reducing costs and reducing the design cycle from months to weeks. The approach 

used involves an optimization routine to coordinate parallel fuel-spray and combustion simulations with 

different injector geometries to hasten convergence on an optimal design. Current efforts are focused on 

developing and validating a high-fidelity multiprocessor simulation tool for more accurate spray modeling 

to enable virtual design and optimization of injectors. Results show good qualitative agreement with 

experimental data over a range of operating conditions, including accurately capturing the transition to 

flash boiling at higher fuel temperatures and lower cylinder pressures (Figure 2). Future efforts will focus 

on additional refinement of the model to better predict plume mixing and the inclusion of combustion to 

evaluate engine performance and efficiency.

During FY 2015, the use of Oak Ridge Leadership Computing Facility HPC resources for the combustion 

stability studies was supported through two DOE Office of Science 2014 Advanced Scientific Computing 

Figure 1. ORNL’s Titan supercomputer. 
2015 Annual Report Vehicle Technologies R&D Highlights

ORNL Sustainable Transportation Program 53

Research Leadership Computing Challenge awards. A Director’s Discretionary Research allocation 

supported GDI fuel injection project efforts on Titan during FY 2015.

Figure 2. Improving predictive models of injector flow and cavitation. Internal nozzle flow simulations 

capture transition to flash boiling at high temperature and low pressure.

Publications, Presentations, and Patents

1. K. D. Edwards, C. E. A. Finney, S. Pannala, W. R. Elwasif, M. K. Stoyanov, R. M. Wagner, and C. S. 

Daw. 2015. “Accelerating Predictive Simulation of IC Engines with High Performance Computing” 

presented at the 2015 DOE Vehicle Technologies Office Annual Merit Review, Crystal City, 

Virginia, June 8–12, 2015. 

2. R. O. Grover Jr., T. W. Kuo, W. R. Elwasif, S. Pannala, K. D. Edwards, and R. M Wagner. 2015. 

“Multi-Hole Injector Optimization for Spark-Ignited Direct-Injection Gasoline Engines.” presented at 

the 2015 OLCF Users Meeting, June 23–25, 2015, Oak Ridge, Tennessee. 

3. C. E. A. Finney, K. D. Edwards, M. K. Stoyanov, and R. M. Wagner. 2015. “Application of High 

Performance Computing for Studying Cyclic Variability in Dilute Internal Combustion Engines.” 

accepted for presentation at the 2015 ASME Internal Combustion Engine Division Fall Technical 

Conference, November 8–11, 2015, Houston, Texas, as ASME ICEF2015-1172, doi: 

10.1115/ICEF2015-1172. 
Vehicle Technologies R&D Highlights 2015 Annual Report

54 ORNL Sustainable Transportation Program

Energy Storage

Nondestructive Evaluation Techniques for Processing High-Energy 

Lithium Ion Batteries

Contact: David L. Wood, III, wooddl@ornl.gov, 865-574-1157

For electric vehicles to successfully compete with vehicles powered by internal combustion engines, 

battery efficiencies must be improved and costs must be brought down. 

One way to bring production costs down and in some cases improve efficiency at the same time is 

through better defect control and elimination of the associated scrap and waste. Currently in-line 

nondestructive evaluation (NDE) techniques used in other industries have not been adapted to the roll-toroll processing used in the lithium ion battery (LIB) industry. Continuous, in-line monitoring and NDE of 

the electrodes during the manufacturing process would improve overall quality and performance of LIBs 

and would help to avoid waste by detecting flaws and defects at or near the manufacturing step where 

they are created, allowing adjustments to prevent additional flaws and defects before final cell assembly. 

ORNL is teaming with battery manufacturers and colleagues at the National Renewable Energy 

Laboratory (NREL) to develop in-line NDE techniques applicable to LIBs. In 2015 they undertook a 

thorough investigation of electrode coating defects, including microstructural analyses of defective 

electrodes, and correlated them with electrochemical performance to better understand the effects of 

specific defects on device performance. Such correlations are essential to establishing pass/fail criteria for 

NDE of electrodes.

The following defects, which diminish battery performance and shorten battery life, were investigated: 

agglomerates, pinholes, nonuniform coating, and metal particle contaminants. The results revealed that 

the type of defect determines the extent of capacity degradation at high discharge rate.

(a) Experimental setup of the infrared detection system for electrode coating defects on an ORNL slot 

die coater. (b) Comparison of the impacts of various types of electrode coating defects on the 

performance of coin cell electrodes compared with the performance of a defect-free baseline electrode 

after 200 full coin cell cycles.
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ORNL Sustainable Transportation Program 55

The ability of infrared (IR) thermography to detect these defects, porosity (which plays a major role in the 

lithium-ion transport process and thus battery efficiency), and other battery characteristics was also 

investigated, with positive results. Further development of a combined defect detection and porosity 

measurement NDE system based on the IR thermography technology will be explored in 2016.

The findings from this research have broad applicability to advanced manufacturing processes and to 

other electrochemical products such as fuel cells, membrane electrolyzers, supercapacitors, flexible 

displays, and flexible sensors. Because of this, the technology development at NREL was funded through 

the DOE Fuel Cell Technologies Office to investigate quality control for fuel cell membrane electrode 

assembly and gas diffusion layers and at ORNL through the DOE Vehicle Technologies Office to 

investigate quality control for battery electrodes. 

Publications, Presentations, and Patents

1. D. Mohanty, J. Li, R. Born, C. L. Maxey, R. B. Dinwiddie, C. Daniel, and D. L. Wood. 2014. 

“Reducing the Scrap Rate in Lithium-Ion Battery Manufacturing by Implementing In-Line NonDestructive Electrode Evaluation Techniques.” presented at the 3rd International Conference and 

Exhibition on Materials Science & Engineering, San Antonio, Texas, October 6–8, 2014. (Invited)

2. D. Mohanty, J. Li, S. Nagpure, D. L. Wood, III, and C. Daniel. 2015. “Correlating Electrode Defects 

with Electrochemical Performance of Lithium-Ion Batteries.” presented at the 2015 MRS Spring 

Meeting and Exhibit, San Francisco, April 6–10, 2015.

3. D. Mohanty, J. Li, C. Daniel, and D. L. Wood. 2015. “Effect of Electrode Manufacturing Defects on 

Electrochemical Performance of Lithium-Ion Batteries; Cognizance of the Battery Failure Sources.” 

Journal of Power Sources (submitted).

Patented Aqueous Processing Technology Demonstrates 

Performance and Durability

Contact: David L. Wood, III, wooddl@ornl.gov, 865-574-1157

Lithium ion batteries (LIBs) are among the leading contenders to provide power for battery electric 

vehicles (BEVs). However, current LIBs are too expensive for BEVs to be competitive with vehicles 

powered by internal combustion engines. Two avenues for major cost reductions are raw materials 

synthesis and materials processing, which combined constitute 80% of the total cost of EV batteries. 

Researchers at the DOE Battery Manufacturing R&D Facility at ORNL are working with battery 

manufacturers, material suppliers, equipment manufacturers, and colleagues at other national labs to 

develop their patented TACLE (tailored aqueous colloids for lithium ion electrodes) technology to 

transform LIB electrode manufacturing by reducing manufacturing costs, mitigating environmental 

impacts, and increasing LIB energy density. 

TACLE, as the definition implies, is an aqueous process for electrode manufacture. Currently most 

cathodes are manufactured using a costly organic solvent, N-methyl-2-pyrrolidone (NMP). NMP is both 

expensive (> $1.25/L) and toxic, produces flammable vapors, and requires expensive machinery and 

costly solvent recovery. In the ORNL TACLE process, NMP is replaced with deionized water ($0.015/L), 

enabling materials and processing cost savings and eliminating the costly NMP recovery process. The 

waterborne binders used in the process are also more environmentally friendly than conventional ones.

In 2015, project researchers concentrated on scaling up the process to larger-format pouch cells; 

incorporating steps and materials to increase electrode conductivity and energy density, including 
Vehicle Technologies R&D Highlights 2015 Annual Report

56 ORNL Sustainable Transportation Program

controlling particle-size distribution, electrode porosity, pore-size distribution, and the porosity gradient 

in the electrodes; investigating the effect of doubling electrode thicknesses on power density; confirming 

potential cost savings from the process; and comparing cell performance to cells made with 

conventionally manufactured electrodes. 

Pouch cells with water-based electrodes exhibited similar capacity and performance to those 

manufactured using conventional techniques up to 600 deep-discharge cycles and were projected to 

outperform them in extended cycling. Also, capacity for the cells with aqueous electrodes could be 

boosted by increasing cell temperature from 25°C to 30°C. However, even without the temperature 

change, capacity retention of the all-aqueous-processed cells was much higher than the baseline cells after 

1,000 cycles, confirming that the electrodes made via aqueous processing have better long-term 

cyclability than conventionally processed electrodes. The additional advancement of doubling electrode 

thicknesses not only will increase power density, but also will reduce costs through use of fewer inactive 

components in cells.

In addition, researchers developed step-by-step guidelines for introducing aqueous processing in existing 

or new LIB manufacturing plants.

Comparison of pouch cell performance with ORNL baseline electrodes, ORNL all-aqueous-processed 

electrodes, and aqueous-processed cathodes with conventionally processed anodes from a prominent 

industry partner: capacity retention under accelerated degradation (a) and rate capability (b).

Publications, Presentations, and Patents

1. J. Li, D. L. Wood, C. Daniel, and B. L. Armstrong. 2015. “Aqueous Processing of Composite 

Lithium Ion Electrode Material.” US Patent 8,956,688 (UT-Battelle, LLC), February 17, 2015.

2. D. L. Wood, J. Li, and C. Daniel. 2015. “Prospects for Reducing the Cost of Lithium Ion Electrode 

Processing and Pouch Cell Formation Steps.” Journal of Power Sources 275, 234–242.
2015 Annual Report Vehicle Technologies R&D Highlights

ORNL Sustainable Transportation Program 57

3. J. Li, C. Daniel, and D. L. Wood. 2015. “Effect of Interface between Current Collector and 

LiNi0.5Mn0.3Co0.2O2 Composite Cathodes on the Electrode Performance.” presented at the 227th ECS

Meeting, Chicago, Illinois, May 24–28, 2015.

4. J. Li, Claus Daniel, and D. L. Wood. 2015. “Coating of LiNi0.5Mn0.3Co0.2O2 Cathode on Various 

Substrates via Slot-Die Coating and Their Performance.” presented at the European Coating 

Symposium 2015, Eindhoven, Netherlands, September 9–11, 2015.

5. D. Wood, J. Li, C. Daniel, and B. L. Armstrong. 2014. “Aqueous Colloidal Chemistry for Low-Cost 

Green Manufacturing of Lithium -Ion Battery Electrodes.” presented at the Materials Science & 

Technology 2014 Symposium on Advanced Solution and Colloidal Processing for Ceramics, 

Pittsburgh, Pennsylvania, October 12–16, 2014 (invited).

State-of-the-Art Diagnostics Applied to High Voltage, High Capacity 

Lithium-Manganese-Rich Cathodes

Contact: David L. Wood, III, wooddl@ornl.gov, 865-574-1157

Affordable high voltage, high capacity batteries will be necessary for battery electric vehicles to displace 

other types of vehicles in transportation applications. Lithium ion batteries (LIBs) made with cathodes of 

lithium-manganese-rich (LMR) oxides are of particular interest because of their high initial capacity and 

operating voltage. However, after a minimum number of charge-discharge cycles, they undergo an 

irreversible structural change that severely degrades performance.

Researchers at ORNL and colleagues at Argonne National Laboratory are using state-of-the-art analytic 

techniques to better understand the nature of this structural change and to determine whether the change 

truly is irreversible.

In 2015, they used the temperature-dependent magnetic susceptibility technique to study structural 

changes and the electronic states of the transition metal ions in the oxide lattices of cathode samples from 

LIB pouch cells. Magnetic susceptibility, based on whether a material is repelled by or attracted to a 

magnetic field, was selected because of its sensitivity in detecting structural changes and related electrical 

properties. 

Using the technique, they were able to show direct evidence of irreversible structural changes in the LMR 

oxides from the pouch cells after a minimal number of charge-discharge cycles (26 in the study). The 

results support the hypothesis that the layered LMR material transforms from a layered to a spinel 

structure with LiMn2O4 as the dominant phase because of the formation of lithium vacancies and oxygen 

loss, which blocks the ion transport pathways in the oxide lattice, leading to capacity and voltage fading. 

The results also demonstrate the utility of the magnetic susceptibility technique for understanding 

structural changes in complex layered oxides.

Publications, Presentations, and Patents

1. D. Mohanty, J. Li, S. Nagpure, D. L. Wood III, and C. Daniel. 2015. “Understanding the Structure 

and Structural Degradation Mechanisms in High-Voltage Lithium-Ion Battery Cathode Oxides: A 

Review of Materials Diagnostics.” MRS Energy & Sustainability 2; doi:10.1557/mre.2015.16.

2. D. Mohanty, A. S. Sefat, E. A. Payzant, J. Li, D. L. Wood III, and C. Daniel. 2015. “Unconventional 

Irreversible Structural Changes in a High-Voltage Li-Mn-Rich Oxide for Lithium-Ion Battery 

Cathodes.” Journal of Power Sources, 283: 423–428.
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58 ORNL Sustainable Transportation Program

Development of spinel structure in lithium-manganese-rich 

oxide cathodes with repeated cycling.
2015 Annual Report Vehicle Technologies R&D Highlights

ORNL Sustainable Transportation Program 59

Lightweight Materials

Advanced Oxidative Stabilization of Carbon Fiber Precursors

Contact: Felix L. Paulauskas, paulauskasfl@ornl.gov, 865-576-3785

The total manufacturing cost of carbon fiber (CF) is one of the single largest obstacles to its incorporation 

in future automotive systems, and 43% of the cost is attributable to the conversion of the precursor into 

CF and activating the surface for resin compatibility. Conventional oxidation, part of the conversion step, 

is a slow thermal process that typically consumes more than 80% of the processing time in a conventional 

CF conversion line. A rapid oxidation process could dramatically increase the conversion line throughput 

and would appreciably lower the fiber cost.

ORNL has been working with RMX Technologies to develop a plasma-processing technique to rapidly 

and inexpensively oxidize polyacrylonitrile precursor fibers to produce lower-cost CF with properties 

suitable for use by the automotive industry. Essential to the success of this project was meeting critical 

technical criteria, including DOE strength goals (≥ 25 Msi tensile modulus, ≥ 250 ksi tensile strength, and 

≥ 1.0% ultimate elongation in the finished fiber); repeatable and controllable processing; and significant 

unit cost reduction compared with conventional processing. FY 2015 was the final year of DOE funding 

for the project, and all project goals and technical criteria have been met.

The technology has been successfully demonstrated to a variety of companies in the CF industry, and 

industry interest is strong. RMX is negotiating to license ORNL’s rights to the intellectual property 

covering plasma oxidation. (RMX already has rights to this intellectual property through co-invention.) 

RMX and its subsidiary, 4M Industrial Oxidation, have already begun scaling up this technology with its 

industry partner, C. A. Litzler Co., Inc., with the goal of demonstrating the technology to industry at a 

scale of 175 MT/year.

Tensile strength of plasma-oxidized, conventionally carbonized fiber vs. conventionally 

oxidized/carbonized fiber (a) and modulus of plasma-oxidized, conventionally carbonized fiber vs. 

conventionally oxidized/carbonized fiber (b). The green dashed arrows project the average 

conventional results to plasma results; the orange dashed lines denote the DOE program minimum. 

The red arrow in (a) points out the large variation in this parameter, which is due to the wide variation 

of carbonization conditions explored at ORNL.
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60 ORNL Sustainable Transportation Program

Publications, Presentations, and Patents

1. F. L. Paulauskas and T. A. Bonds. 2015. “Advanced Oxidation and Stabilization of PAN-Based 

Carbon Precursor Fibers.” presented at the 2015 US Department of Energy Hydrogen and Fuel Cells 

Program and Vehicle Technologies Office Annual Merit Review and Peer Evaluation Meeting on 

June 11, 2015.

Better Predictive Engineering Tools for Improved Thermoplastic 

Composites

Contact: Vlastimil Kunc, kuncv@ornl.gov, 865-919-4595, and C. David Warren, warrencd@ornl.gov, 

865-574-9693

The strength of fiber-reinforced composite materials is related to the length and orientation of the 

reinforcing fibers. Longer fibers impart greater load-bearing strength to the matrix, and such composites 

are typically stronger in the orientation direction of the fibers. One of the problems for automotive 

component design using chopped carbon fibers (CFs) is the lack of validated models.

ORNL is leading a project to validate three-dimensional models for long-fiber-reinforced, thermoplastic 

(LFT), injection-molded composites containing CF. Advanced characterization techniques are being used 

to generate a database of experimental results for the CF orientation and CF length distribution within a 

component. Computational models that have been validated using a part with features representative of an 

automotive component and the database of results will be made available to the general public via the 

World Wide Web. Additionally, this predictive technology led to the creation of a demonstration part that 

led to production implementation of a CF-LFT oil pan by Ford Motor Company. 

In FY 2015 the project team molded plaques and complex parts with four material compositions using 

qualified equipment and a combination of fast and slow fill speeds and high and low back pressures. Fiber 

orientations and fiber lengths were measured using previously reported techniques. Most of the 

experimental work has been completed, and predictions for complex parts can now be finalized before the 

experimental results for the complex part are released for comparison. During FY 2016, the team 

anticipates completing flow simulation for the complex part and reporting on the comparison of flow 

simulations and experimental measurements for the part.

The fiber orientation and fiber length prediction models validated in this project will be commercially 

available through Moldex 3D Northern America Inc. Experimental data used for validation will be 

available in a publically accessible format. Additionally, other industry participants on the project have 

indicated production intent. 

Ultimately, the results of this project will enable the optimal design of lightweight automotive structural 

components using injection-molded LFTs.

Publications, Presentations, and Patents

None to report this period.
2015 Annual Report Vehicle Technologies R&D Highlights

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Fiber orientation distribution (FOD) sample being imaged (a) and example FOD image (b).

Corrosivity and Passivity of Metastable Magnesium Alloys

Contact: M. P. Brady, bradymp@ornl.gov, 865-574-5153

One way to improve fuel economy is to make vehicles lighter, sometimes referred to as “lightweighting.” 

The high strength-to-weight ratio and castability of magnesium, the lightest of the structural metals, make 

it a good candidate for automotive lightweighting; however, traditionally its use has been low. One reason 

is its low corrosion resistance. Coupled with this is the fact that it is prone to galvanic corrosion when in 

contact with other metals—as is the case in many vehicle applications.

ORNL researchers have made significant efforts to understand the corrosion behavior and to improve the 

corrosion performance of magnesium alloys. Surface alloying offers the potential to dramatically enhance 

corrosion resistance without significantly altering a material’s bulk properties and density. It may be 

possible to obtain a corrosion-resistant magnesium alloy through alloying with passivating elements such 

as Cr, Ti, Al, and Ni. The matrix phase, which is weakly corrosion resistant and thus preferentially 

attacked by corrosion, is a critical factor in magnesium alloy corrosion. Passivating the matrix phase 

through alloying with a strong passivating element would be a significant step toward improvement in 

overall corrosion resistance of magnesium alloys.

In this project the possibility of forming a passive film on magnesium alloys through adding strong 

passivating elements in metastable magnesium solid solution was investigated. The project manufactured 

and compared the behavior of ingot and magnetron-sputtered pure magnesium relative to magnetronsputtered magnesium-titanium (Mg-Ti) and magnesium-chromium (Mg-Cr) alloys. A transition to 

passive-like behavior was observed for both Mg-Ti and Mg-Cr; however, the transition only occurred if 

the level of Ti or Cr exceeded that of the Mg (in atomic percent)—effectively shifting the alloy to Ti or Cr 

base. While this is of limited utility for conventional magnesium alloy design, insights from this research 

might prove beneficial to new classes of complex, multiple-element, high-entropy alloys. The findings

may also provide guidance for coating approaches that enrich the local surface of an Mg alloy in Cr or Ti 

as both elements are commonly used in conversion coating strategies.
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62 ORNL Sustainable Transportation Program

Polarization curves for pure magnesium and select 

magnetron-sputtered Mg-Cr and Mg-Ti alloys in saturated 

Mg(OH)2 + 0.1 wt % NaCl solution. Alloy polarization curves 

shifted to the right and downward on the plot compared to 

the pure magnesium control curve, indicating an improved 

degree of corrosion resistance.

Publications, Presentations, and Patents

1. G. L. Song and K. A. Unocic. 2015. “The Anodic Surface Film and Hydrogen Evolution on Mg.” 

Corros. Sci. 98: 758–765.

2. G. L. Song, K. A. Unocic, H. M. Meyer III, E. Cakmak, M. P. Brady, P. E. Gannon, P. Himmer, and 

Q. Andrews. 2016. “The Corrosivity and Passivity of Sputtered Mg-Ti Alloys.” Corros. Sci. 104: 36–

46. 

3. G. L. Song and P. E. Gannon. 2016. “The Surface Films and Their Possible Roles for Mg Corrosion.” 

presented at the 2016 TMS Annual Meeting and Exhibition, February 14–18, 2016, Nashville, 

Tennessee, and published in Magnesium Technology 2016 (A. Singh, K. Solanki, M. V. Manuel, and 

N. R. Neelameggham, eds.), 285–290, John Wiley & Sons, Inc., Hoboken, New Jersey; doi: 

10.1002/9781119274803.ch56. 

DOE Carbon Fiber Technology Facility Continues to Chart Low-Cost 

Fiber Course

Contact: Ronald Ott, ottr@ornl.gov, 865-574-5172

ORNL is home to the DOE Carbon Fiber Technology Facility (CFTF), a 42,000 ft2 innovative technology 

facility offering a unique, highly flexible, highly instrumented carbon fiber line for demonstrating 

advanced technology scale-up and for producing market-development volumes of prototypical carbon 

fibers. CFTF serves as a national test bed for government and commercial partners to scale up emerging 

carbon fiber technology. 

CFTF has been focused on addressing technical challenges that impact the cost per unit volume of carbon 

fiber. Significant advancements have been made in this area and in increasing the performance of textilebased polyacrylonitrile (PAN) carbon fiber precursors. During 2015, the following significant advances 

were made with textile-based PAN precursors and the carbon fibers made from them. 
2015 Annual Report Vehicle Technologies R&D Highlights

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Modulus of the textile-based carbon fiber was increased to 41 Msi, with tensile strength of 423 ksi and 

greater than 1% strain. This meets the strength requirements of the automotive industry for carbon fiber 

composite structural applications. In addition, CFTF doubled the throughput volume of these same 

textile-based carbon fibers, which will have a significant impact on reducing operational cost per unit 

volume of carbon fiber.

CFTF conducted a 2-week nonstop baseline run with standard 24 K 

industrial-grade commercial PAN precursor to demonstrate process 

consistency and equipment reliability in a long continuous run. 

During this trial, 1,293 lb of carbon fiber was produced with an 

average tensile strength of 517 ksi (standard deviation 37.9) and 

tensile modulus of 34.1 Msi (standard deviation 0.4). The carbon fiber 

scrap rate was 2.1% of total carbon fiber produced. The start-up and 

shutdown precursor waste rate was 11% of total precursor consumed. 

A precursor prestretch simulation was performed to demonstrate the 

value to the conversion process of prestretching textile PAN and other 

alternative precursors. The initial simulation showed that the 

mechanical properties were unaffected by the prestretching vs. 

oxidative stretching, but the line speed could be increased by 20%. 

Additional trials are needed to engineer the equipment specifications 

of the prestretch station.

In addition, 650 visitors representing 110 companies toured CFTF, 

and CFTF produced 15,165.2 kg of carbon fiber, 12,407.2 kg of which was transferred to outside 

companies and research organizations for further research.

Future directions include developing multiple alternative precursor materials and economically attractive 

processing conditions to support them.

Publications, Presentations, and Patents

1. R. Ott. 2014. “Carbon Fiber Technology Facility Update.” presented to the Oak Ridge Carbon Fiber 

and Composites Consortium, Knoxville, Tennessee, October 28, 2014.

2. C. Jackson. 2014. “Manufacturing of Low-Cost Carbon Fiber from Unmodified Textile PAN Fiber.” 

presented at the Composites World 2014 Conference, La Jolla, California, December 10, 2014.

3. R. Ott. “ORNL Manufacturing Demonstration Facility and Carbon Fiber Technology Facility.” 

presented at the American Carbon Society Workshop, Oak Ridge, Tennessee, April 16, 2015.

4. R. Chambers, J. Crabtree, and C. Jackson. Method of Measuring Density of Oxidized and Carbonized 

Fibers In-Situ. Invention disclosure 201503593, September 2015.

5. C. Jackson. Method of Producing Carbon Fibers from Multipurpose Commercial Fibers. Invention 

disclosure 201503583, September 2015.

6. C. Jackson. Modular Line Configuration for Carbon Fiber Conversion. Invention disclosure 

201403438, December 2014.

Four bands of large tow fibers 

entering the oxidation ovens. 
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64 ORNL Sustainable Transportation Program

Laser-Assisted Joining Process for Aluminum and Carbon Fiber 

Components Enables Use in Primary Automotive Structures

Contact: Adrian Sabau, sabaua@ornl.gov, (865) 241-5145

ORNL has demonstrated a breakthrough laser-structuring technology for joining carbon fiber polymer 

composites (CFPCs) and aluminum components. The innovations included texturing the aluminum and 

CFPC surfaces using a laser-interference technique, engineering rough surfaces before an adhesive 

bonding operation. 3M Company provided the adhesives; Plasan Carbon Composites, Inc., provided the 

composite; and Cosma, Inc., provided the aluminum. 

Joining carbon fiber composites and aluminum for lightweight cars and other multimaterial high-end 

products could become less expensive, and the joints could be more robust because of this new method, 

which harnesses a laser’s power and precision. Using an interference-based laser technique to either 

structure the surfaces or remove layers of material from surfaces before bonding improves the 

performance of the joints and provides an efficient, repeatable production process that can be automated 

for high-volume use.

ORNL’s research effort focused on demonstrating the effect of the laser-interference structured surfaces 

of the aluminum and CFPC materials on joint performance. The following quality indicators were used 

for assessing joint performance: shear-lap strength, maximum load, displacement at which the maximum 

load was recorded, energy stored in the joint during tensile testing, and mode of failure (failure in the 

adhesive or failure in one component). 

A significant increase in the mechanical properties of the shear-lap joints, which were made with laserstructured surfaces, compared to the baseline data demonstrated the proof of concept for the use of laserstructuring and/or laser-ablation technology for surface preparation of both CFPC and aluminum coupons 

before adhesive joining. 

For a bondline thickness of 0.85 mm, the mechanical testing results showed that shear lap strength, 

maximum load, and displacement at maximum load were increased by 40%, 28%, and 100%, 

respectively, over those measured for the baseline joints. Also, joints made with laser-structured surfaces 

were found to absorb about 200% more energy than the conventionally prepared baseline joints. The 

maximum possible mechanical strength for the double-lap aluminum-CFPC joints was attained with 50% 

of the failure points occurring in the aluminum coupon, away from the joint. 

Ultimately, two project participants, Cosma and Plasan, have the ability to commercialize this technology, 

which is attractive because the use of lighter weight, adhesively joined materials in automotive 

applications would reduce gas consumption and production of greenhouse gasses.

Publications, Presentations, and Patents

1. S. Sabau, C. M. Greer, J. Chen, C. D. Warren, and C. Daniel. 2016. “Surface Characterization of 

Carbon Fiber Polymer Composites and Aluminum Alloys after Laser Interference Structuring.” JOM

68: 1882–1889. 

2. S. Sabau, J. Chen, C. D. Warren, D. L. Erdman III, C. Daniel, T. Skszek, and M. Caruso Dailey. 

2016. “Laser Interference-Based Surface Treatment of Al and Carbon Fiber Polymer Composites for 

Enhanced Bonding.” paper LB15-0070, SAMPE Conference and Exhibition, Long Beach, California, 

May 23–26, 2016.
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ORNL Sustainable Transportation Program 65

3. J. Chen, A.S. Sabau, J. F. Jones, A. Hackett, G. D. Jellison, C. Daniel, and D. Warren. 2015. 

“Aluminum Surface Texturing by Means of Laser Interference Metallurgy.” in 2015 TMS Annual 

Meeting & Exhibition, Proceedings: Light Metals 2015: Aluminium Processing, Orlando, Florida.

4. A. S. Sabau, J. Chen, J. F. Jones, A. Hackett, G. D. Jellison, C. Daniel, D. Warren, and J. D. Rehkopf. 

2015. “Surface Modification of Carbon Fiber Polymer Composites after Laser Structuring.” in 

Advanced Composites for Aerospace, Marine, and Land Applications II. T. Sano and T. S. Srivatsan, 

eds., John Wiley & Sons, Inc., Hoboken, New Jersey; doi: 10.1002/9781119093213.ch23.

(a) (b)

(c)

Pictures taken after mechanical testing of double-lap joints bonded with adhesive 

DP810 showing fracture surfaces and/or failure modes: (a, b) baseline joints (c) joints 

with laser-structured surfaces using a laser beam size of 6 mm. 

Enabling Multimaterial Next-Generation Vehicles

Contact: C. David Warren, warrencd@ornl.gov, 865-574-6098; Michael P. Brady, bradymp@ornl.gov, 

865-574-5153; and Zhili Feng, fengz@ornl.gov, 865-576-3797

DOE has estimated that using lightweight components and high-efficiency engines in just a quarter of 

vehicles on the road could save more than 5 billion gallons of fuel annually by 2030. While lightweight 
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66 ORNL Sustainable Transportation Program

materials are making inroads in vehicles, most vehicles are still nearly 50% conventional steel. The 

multimaterial enabling project at ORNL is aimed at removing barriers to greater use of lightweight 

materials in vehicles, including lowering costs and developing enhanced processing techniques to handle 

these materials. Currently the project consists of three separate tasks: (1) developing a deeper 

understanding of protective film formation in magnesium alloys, (2) developing and commercializing a 

rapid, in-line, nondestructive evaluation (NDE) method for inspecting spot welds in an automotive 

production environment, and (3) developing a novel method for mitigating weld fatigue in advanced highstrength steels (AHSSs).

Protective film formation in magnesium alloys

Magnesium alloys are of interest to automotive manufacturers because of their high strength-to-weight 

ratio (highest of all structural metals), castability, and recycling potential. However, they are susceptible 

to corrosion, particularly in harsh automotive environments. The inability of magnesium alloys to 

establish a continuous and fully protective surface film under many exposure conditions is a key factor 

underlying their susceptibility to corrosive attack. Alloying and/or conversion coatings have been shown 

to modify surface film performance; however, a detailed understanding of how and why is currently 

lacking. 

The goal of this task is to develop an improved understanding of how alloy composition, microstructure, 

and exposure conditions affect the establishment, continuity, nature, and growth of protective films on 

magnesium alloys. To accomplish this goal, researchers have used advanced characterization techniques 

not previously widely applied to magnesium surface film formation, and a major ancillary goal of the 

project is to assess which advanced characterization techniques are most amenable to providing new 

insights into film formation on magnesium alloys. These results will then serve as baseline information 

for evaluation of more corrosive environments (e.g., salt species), modified alloy compositions, and 

conversion coatings.

Work in FY 2015 focused on three main magnesium corrosion activities: (1) secondary ion mass 

spectrometry (SIMS) isotopic tracer aqueous film growth studies in the presence of salt; (2) studies of 

hydrogen uptake in aqueous exposures as a function of Al, Nd, and Zr alloying additions to Mg; and 

(3) studies on the effect of substrate composition on conversion coating formation in the as-conversioncoated condition and after subsequent e-coating.

Cross-section transition electron microscopy with sample preparation by focused ion beam techniques has 

proven particularly useful in understanding film/coating structure and chemistry. Application of the SIMS 

isotopic tracer study approach to magnesium corrosion is a key outcome of this project, with feasibility 

established for aqueous conditions with and without salt species and for elevated-temperature, humid-air 

oxidation. Given the formation of oxide-hydroxide films by magnesium, tracers incorporating both 18O 

and deuterium can provide unique insights not achievable by other techniques. An unexpected finding 

was enhanced hydrogen uptake as a result of aqueous exposure in magnesium alloys containing zirconium 

and neodymium. This is potentially relevant to magnesium alloy design from a hydrogen embrittlement 

and stress corrosion cracking perspective and to functional use of magnesium alloys (e.g., in batteries or 

hydrogen storage). Although further work is needed, this research suggests a number of paths forward to 

more corrosion-resistant magnesium alloys, including advanced characterization of substrate–alloycoating interfaces to optimize the synergy between alloy composition and subsequent conversion coating 

chemistry and structure and possible modification of coating parameters to avoid degradation of the 

initially formed conversion coating surface.
2015 Annual Report Vehicle Technologies R&D Highlights

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Fraction 18O/(18O+16O) secondary ion mass 

spectrometry data (counts per second vs. sputtering 

depth) for commercial alloy Elektron 717 (a rare earth–

zirconium magnesium alloy). Water-only exposure was 

4 h D2O + 20 h 18O water. Salt exposure was 4 h D2O + 

20 h 18O water with 0.01 wt % NaCl. Zero sputtering 

time corresponds to the film surface. The dip in the salt 

exposure data indicates a shift to mixed outward/inward 

film growth compared to inward-dominated film growth 

in pure water.

Online Weld NDE with Infrared Thermography

The development of resistance spot welding (RSW) for AHSSs is critical for enabling the broader 

implementation of AHSSs in vehicle structures for lightweighting and crashworthiness. Variations in 

welding conditions, part “fit-up,” and other production conditions can result in out-of-tolerance joints that 

impair the quality and performance of vehicles. The increasing use of AHSSs and other lightweight 

metals is expected to pose even more stringent requirements on joint quality in the future. Thus, reliable 

quality inspection techniques are crucial for determining the quality of joints on the assembly line.

In FY 2011–2014, a prototype infrared-based system was developed for both real-time (online) and postweld (online/offline) inspection applications. The inspection cycle is 1–2 seconds, fast enough to measure 

each weld made during the welding operation and to provide industry with a low-cost, nondestructive 

method for monitoring welds in real time. The system was extensively tested in the laboratory, where 

tests showed that it was able to positively identify welding defects, including lack of fusion and excessive 

indentation. In FY 2015, this technology was licensed by APLAIR Manufacturing Systems, a Tennesseebased company. ORNL is assisting APLAIR in scaling up the technology and prototype system to a 

commercial product. APLAIR plans to have a commercial product within 2 years. 

The net result is that automakers now have an efficient method for sending immediate feedback to the 

production lines to correct weld quality issues, potentially saving the US automotive industry hundreds of 

millions of dollars per year. This new ORNL technology is a key enabler for automaker adoption of 

advanced high-strength, lightweight auto-body materials, which are more difficult to weld and inspect but 

will improve the fuel efficiency and safety of the vehicle fleet. As RSW is the primary auto-body 

assembly process for automotive companies worldwide, this new NDE technology has the potential to 

revolutionize the welding and assembly of automotive body structures.
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68 ORNL Sustainable Transportation Program

Improving Fatigue Performance of AHSS Welds

Durability is one of the primary metrics in designing and engineering automotive body structures. Fatigue 

performance of welded joints is critical to the durability of body structures because the likeliest locations 

for fatigue failure are often at welds. Today’s weld fatigue improvement techniques are mostly post-weld 

based. The added steps are cost prohibitive in the high-volume mass-production automotive environment, 

and large variability exists in the fatigue life achieved by the postweld–based techniques. In this project, 

ORNL and industry partner ArcelorMittal worked together to develop effective in-process ways to control 

and mitigate the key factors governing the fatigue life of AHSS welds, including weld residual stress, 

weld profile, and weld microstructure/chemistry. The joint research used state-of-the-art integrated 

computational welding engineering; neutron, synchrotron, and other advanced residual stress 

measurement techniques; and fatigue testing and microstructure analysis capabilities at ORNL to perform 

project R&D.

The project was successfully completed during FY 2015. Weld fatigue life improvements of 3 to 5 times 

and 5 to 10 times were demonstrated using two novel approaches developed during the project to control 

and mitigate the weld residual stresses. The improvements in weld residual stresses could also drastically 

change the welding-induced distortion in thin sheet steels used for auto-body structural components. The 

potential of ORNL–US Army–developed low transformation temperature weld wires to mitigate 

hydrogen-induced cracking in welding of high-strength steels was also demonstrated during the project. 

While the project focused on AHSSs, the techniques developed may also be applicable to welding of 

other lightweighting materials such as aluminum and magnesium alloys.

Comparison of weld fatigue lives of baseline ER70-S 

filler wire vs. the new filler wire developed during this 

project.

Publications, Presentations, and Patents

1. M. P. Brady, M. Fayek, H. M. Meyer, D. N. Leonard, H. H. Elsentriecy, K. A. Unocic, L. M. 

Anovitz, E. Cakmak, J. R. Keiser, G.-L. Song, and B. Davis. 2015. “Tracer Study of Oxygen and 

Hydrogen Uptake by Mg Alloys in Air with Water Vapor.” Scripta Materialia 106: 38–41.

2. M. P. Brady, G. Rother, L. M. Anovitz, K. C. Littrell, K. A. Unocic, H. H. Elsentriecy, G. L. Song, 

J. K. Thomson, N. C. Gallego, and B. Davis. 2015. “Film Breakdown and Nano-Porous Mg(OH)2 

Formation from Corrosion of Magnesium Alloys in Salt Solutions.” Journal of the Electrochemical 

Society 162(4): C140–C149.
2015 Annual Report Vehicle Technologies R&D Highlights

ORNL Sustainable Transportation Program 69

3. J. Chen, Z. Feng, and W. Zhang. W. Software, IR Spot Weld Inspector. Copyright 50000074, April 

2014.

4. Z. Feng, Z. Yu, S. David, and D. Tzelepis. High-Strength Weld Wire for Hydrogen Embrittlement 

Control. US Patent Application 14/614,439, Filed February 5, 2015.

5. G.-L. Song, et al. 2014. “Film Evolution on Mg Alloys.” presented at Materials Science & 

Technology 2014, Pittsburgh, October 12–16, 2014.

6. Z. Wang, Z. Yu, and Z. Feng. 2015. “Effect of Low Transformation Temperature Welding 

Consumables on the Weld Microstructure and Mechanical Properties.” presented at the 2015 AWS 

Annual Convention, Chicago, 2015.

7. Z. Wang, Z. Yu, Z. Feng, and S. Liu. 2014. “Effect of Low Transformation Temperature Welding 

Consumables on Mechanical Properties of Lap Joints.” presented at the 2014 AWS Annual 

Convention, Atlanta, 2014.
Vehicle Technologies R&D Highlights 2015 Annual Report

70 ORNL Sustainable Transportation Program

Power Electronics and Electric Motors

ORNL Demonstrates 10 kW Bidirectional Wireless Power Transfer 

System 

Contact: Omer C. Onar, onaroc@ornl.gov, 865-946-1351

ORNL developed and demonstrated the world’s first level 2 (10 kW) bidirectional wireless power transfer 

system. The system achieved efficiencies greater than 90% and charging speeds equivalent to plug-in 

charging. 

The bidirectional wireless charging system offers flexibility with several architectures available along 

with dc and ac interfaces for energy storage and grid applications. As part of the development process, 

researchers conducted simulations and experimental evaluation of the use case scenarios. The 

bidirectional wireless charger can transfer power between the stationary (home) energy storage system 

and the vehicle battery. The vehicle can be powered from the grid, and the vehicle can power the building 

loads, or power can be transferred to the grid. 

With this capability, the vehicle can be used as an emergency backup power source, and several benefits 

can be realized on the customer side of the meter (e.g., peak shaving; improvements in power factor, load 

factor, and power quality; reactive power compensation; time-of-use energy management; demand charge 

management; and renewables integration). The system can also provide a target amount of power to the 

grid, which enables the grid ancillary services such as regulation, spinning/nonspinning reserves, and 

voltage control. 

ORNL demonstrated the bidirectional wireless charging technology through the Additive Manufacturing 

Integration Energy (AMIE) project. AMIE leveraged expertise across the ORNL programs funded by the 

DOE Office of Energy Efficiency and Renewable Energy, bringing together researchers and resources 

focused on vehicles, manufacturing, and buildings. The team created a novel printed utility vehicle (PUV) 

and a building that exchange energy via smart controls and bidirectional wireless power transfer. 

The AMIE PUV generates energy using a hybrid electric powertrain with a small (5.5 kW) 

engine/generator fueled by two compressed natural gas storage tanks. Energy flows from the generator to 

the PUV battery to the charging coil attached to the underside of the car. When the PUV is parked, the 

vehicle charging coil sends energy across an air gap to a wireless charging pad on the ground. Inductive 

charging transfers the energy from coil to coil. The charging pad sends electricity to the building, where it 

can power appliances or recharge the home’s battery. 

The AMIE project offers a platform for evaluating new technologies and integrated energy systems that 

increase efficiency for transportation, buildings, and the grid. 

Publications, Presentations, and Patents

1. M. Chinthavali, O. C. Onar, S. L. Campbell, Z. Wang, C. P. White, and L. Seiber. 2016. “A 10-kW 

Level-II Bidirectional Wireless Power Transfer System for Grid Services and Export Power.” 

submitted to the IEEE Applied Power Electronics Conference and Exposition, March 2017. 

2. J. M. Miller, P. T. Jones, J.–M. Li, and O. C. Onar. 2015. “ORNL Experience and Challenges Facing 

Dynamic Wireless Power Charging of EVs.” IEEE Circuits and Systems Magazine 15(2) 40–53. May 

2015.
2015 Annual Report Vehicle Technologies R&D Highlights

ORNL Sustainable Transportation Program 71

3. J. M. Miller, O. C. Onar, and M. Chinthavali. 2014. “Primary Side Power Flow Control of Wireless 

Power Transfer for Electric Vehicle Charging.” IEEE Journal of Emerging and Selected Topics in 

Power Electronics—Special Issue on Wireless Power Transfer 3(1), 147–162. December 2014.

4. O. C. Onar. 2015. “Recent Advances in Wireless Power Transfer Systems.” IEEE Applied Power 

Electronics Conference and Exposition, Industry Special Session on Recent Development in Wireless 

Power Transfer, March 2015, Charlotte, NC.

5. J. M. Miller (Moderator), T. Bohn, O. C. Onar, J. Taiber, and M. de Rooji. 2015. “Wireless Power 

Transfer: Facts and Fictions.” RAP Session at the IEEE Applied Power Electronics Conference and 

Exposition, March 2015, Charlotte, NC.

6. O. C. Onar. 2014. “Electric Vehicles without Plugging-In.” Presentation at the University of 

Tennessee Science Forum, November 2014, Knoxville, Tennessee.

7. O. C. Onar.2014. “Electric Vehicles without Plugging-In” Presentation to the Technical Society of 

Knoxville, November 2014, Knoxville, Tennessee.

Steven Campbell works with the 

electronics that enable wireless controls 

and communications between the grid 

and the wireless charging coils in the 

ORNL bidirectional wireless power 

transfer system.
Vehicle Technologies R&D Highlights 2015 Annual Report

72 ORNL Sustainable Transportation Program

Bidirectional wireless charging technology enabled energy to flow 

between this novel printed vehicle and building as part of the 

Additive Manufacturing Integrated Energy demonstration project. 

ORNL’s Innovative Onboard Battery Charger Technology: Double the 

Power Density at Half the Cost

Contact: Gui-Jia Su, sugj@ornl.gov, 865-946-1330

The stand-alone onboard battery chargers (OBCs) and 14 V dc-dc converters that are currently prevalent 

in plug-in electric vehicles and all-electric vehicles are bulky (~0.41 kW/kg, ~0.66 kW/L), are not costeffective (~$106/kW), and have relatively low efficiency (85%–92%) because of the limitations of current 

semiconductor and magnetic materials. In addition, they are unidirectional; that is, they can charge the 

battery but are not capable of vehicle-to-grid support, a highly desirable function for future smart grids. 

ORNL plans to leapfrog these limitations in a multiyear project to replace current silicon-based charger 

technology with wide bandgap (WBG) silicon carbide (SiC) devices, advanced magnetic materials, and a 

novel integrated charger architecture and control strategy.

A major task for FY 2015 was designing, building, and testing an all-SiC 6.8 kW bidirectional OBC 

prototype that integrates a 6.8 kW isolation converter into a 100 kW segmented traction inverter. The 

architecture reduces the number of components significantly (a 47% reduction in power circuit 

components alone, not counting savings in the gate driver and control logic circuits), translating to a 50% 

reduction in cost and volume compared with existing stand-alone OBCs. In addition, SiC-based devices 

are used in the converter and inverter to further reduce the cost, weight, and volume of the passive 

components and improve system efficiency. The isolation converter has a built-in 2 kW, 14 V buck 

(voltage-reducing) converter to meet vehicle accessory electrical loads and an ORNL-developed control 

strategy to reduce the battery ripple current that is inherent in single-phase ac-dc converters. Test results 

show that the control strategy reduces the ripple current by 60% and thereby enables a corresponding 

reduction in the size of the bulky dc link capacitor in the ac-dc front-end converter. Test results also 

showed a high charging efficiency with a peak value of 96.5% and an improvement of more than 2% over 

a silicon-based counterpart. Work planned for FY 2016 will focus on further reducing the weight and 

volume of the isolation converter by using gallium nitride devices and advanced packaging technology.
2015 Annual Report Vehicle Technologies R&D Highlights

ORNL Sustainable Transportation Program 73

ORNL’s all-SiC 6.8 kW bidirectional OBC prototype with integrated 

6.8 kW isolation converter and 100 kW segmented traction inverter.

Publications, Presentations, and Patents

1. G. J. Su. 2014. “Innovative Technologies for Converters and Chargers.” presented at the DOE 

Vehicle Technologies Office Electric Drive Technologies Advanced Power Electronics and Electric 

Motors R&D FY 2015 Kickoff Meeting, Oak Ridge, Tennessee, November 18–20, 2014.

2. G. J. Su. 2015. “Innovative Technologies for Converters and Chargers.” presented at the 2015 DOE 

Hydrogen and Fuel Cells Program and Vehicle Technologies Office Annual Merit Review and Peer 

Evaluation Meeting, Arlington, Virginia, June 8–12, 2015.

3. G. J. Su and L. Tang. 2015. “An Integrated Onboard Charger and Accessory Power Converter using 

WBG Devices.” in Proceedings of the 7th IEEE Energy Conversion Congress and Exposition (ECCE 

2015), 6306–6313, Montreal, Canada, September 20–24, 2015.

Sintered-Silver Interconnect Technology for High-Performance 

Wide-Bandgap Devices

Contact: Andrew Wereszczak, wereszczakaa@ornl.gov, 865-946-1543, or Zhenxian Liang, 

liangz@ornl.gov, 865-946-1467

Wide-bandgap (WBG) semiconductors such as those made from silicon carbide (SiC) permit devices to 

operate at much higher temperatures, currents/voltages, and frequencies—making power electronic 

modules using these materials significantly more powerful and energy efficient than those made from 

conventional silicon semiconductors. They also offer greater efficiency in converting electrical power and 

in operating the electric traction drive during vehicle use.

Sintered-silver die bonding or interconnection is part of a comprehensive ORNL program, sponsored by 

the DOE Vehicle Technologies Office, to bring all-SiC power modules to market through advanced 

packaging technologies that exploit SiC’s superior performance in such devices. 

Current state-of-the-art interconnects (die bonds) are soldered, but the sintered-silver interconnect is quite 

different. The silver bond forms from a paste (composed of micron and submicron silver particles and 

other additives) during the sintering process and is known to be a superior die attachment material 

compared with a solder layer. It offers much better electrical, thermal, and especially thermomechanical 
Vehicle Technologies R&D Highlights 2015 Annual Report

74 ORNL Sustainable Transportation Program

properties for power module packaging. These properties are especially critical to SiC power devices, 

allowing them to operate at temperatures higher than those of silicon devices. Silver sintering currently 

also includes an additional process of mechanically pressing the stack of dies and substrates during 

heating that ORNL is attempting to eliminate via other process modifications. The quality of the bond 

formed between die and substrate can be affected by many factors, such as finishing metals on the die and 

substrate, geometry of the die, patterns on the substrate, and process parameters—pressure, heating 

temperature, and heating time. The ORNL-led research is aimed at a deeper understanding and process 

refinement of sintered-silver interconnection. The ultimate goal is to determine the elements necessary to 

consistently produce reliable sintered-silver joints as economically as possible.

During 2015, custom-designed sintered-silver test coupons were fabricated to enable measurement of 

shear strength, perform failure analyses, and examine the effect of coefficient-of-thermal-expansion–

induced residual stress on sintered-Ag joints and the onset of delamination of the interconnect. 

The shear strengths of sintered-silver interconnect systems were on the order of 40 to 50 MPa—about 

twice the strength of soldered joints. Preliminary failure analysis showed the concurrency of different 

failure mechanisms that limit those strengths. It also indicated that power electronic devices having 

sintered-silver interconnects should be designed so that the maximum service stress is some fraction 

(safety factor) of the measured shear stress. Additional efforts are planned for FY 2016 that will further 

increase the versatility of and confidence in the processing and that will promote greater receptiveness to 

this technology.

Sintered-silver technology: (a) cross-sectional schematic of an SiC die bonded onto a direct-bonded 

copper (DBC) substrate, showing where the silver-sintering process is used for die attachment, and (b) 

examples of preliminary sintered-silver bonding of SiC to either silver- or gold-plated DBC substrates.

Publications, Presentations, and Patents

1. A. Wereszczak, Z. Liang, M. K. Ferber, and L. D. Marlino. 2014. “Uniqueness and Challenges of 

Sintered Silver as a Bonded Interface Material.” Journal of Microelectronics and Electronic 

Packaging 11: 158–165.

2. A. A. Wereszczak, Z. Liang, and T. A. Burress. 2015. “Enabling Materials for High-Temperature 

Power Electronics.” presented at the 2015 VTO AMR, Arlington, Virginia, June 10, 2015.

3. A. A. Wereszczak, S. B. Waters, and W. Carty. Transfer Method for Printed Sinterable Paste Having 

Nonaqueous Solvent. Invention Disclosure Number 201503508, DOE S-138,140, April 4, 2015.
2015 Annual Report Vehicle Technologies R&D Highlights

ORNL Sustainable Transportation Program 75

4. A. A. Wereszczak and W. Carty. Drying Method for Sinterable Paste Used for Bonded Joints. 

Invention Disclosure Number 201503507, DOE S-138,139, April 3, 2015.

USDrive–DOE, Delphi Partner on New Chevrolet Volt Inverter

Contact: Burak Ozpineci, Burak@ornl.gov, 865-946-1329

The 2016 Chevrolet Volt uses a second-generation “Voltec” extended-range electric powertrain with a 

traction power inverter module (TPIM) designed to increase efficiency, performance, and durability. 

Technology innovations developed as part of a USDrive-DOE cofunded project contributed to the design 

of Delphi’s novel dual-side cooled package, which is used as the power device in the Volt TPIM.

Key to the project’s success was Delphi’s development of a silicon dual-side cooled power device 

package. The Delphi device delivers more uniform current density than traditional single-sided power 

modules and is composed of a material stack in which the coefficients of thermal expansion (CTEs) of the 

layers are matched. (Failure in a power module typically is caused by thermal cycling. Mismatching 

CTEs can lead to adhesion issues and cracks and can make layers detach.) Both sides of the device are 

attached to ceramic substrates that are CTE-matched to the silicon. 

ORNL developed a test plan for evaluating the final power module prototype built by Delphi, and the 

testing was completed in collaboration with Delphi. ORNL evaluated the 600 V package over a wide 

range of temperatures (25°C to 150°C), currents (10 A to 300 A), and voltages (250 V to 325 V). The 

device level test data were used to develop behavioral loss models that were incorporated into the systemlevel model.

The National Renewable Energy Laboratory also contributed to the project, providing thermal modeling 

of various polymeric thermal interface materials for use in the Delphi thermal stack.

Publications, Presentations, and Patents

None to report this period.

Power-dense, robust traction power inverter for 

the second-generation Chevrolet Volt extendedrange electric vehicle.
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76 ORNL Sustainable Transportation Program

Propulsion Materials

Stronger, Lower Cost Alloys for Higher Temperature Exhaust Valves 

Improve Vehicle Efficiency

Contact: Govindarajan Muralidharan, muralidhargn@ornl.gov, (865) 574-4281

Exhaust valve temperatures are anticipated to increase in future high-efficiency engines. Temperatures 

could increase from 870°C today to 950°C in 2025 and to 1,000°C by 2050 in light-duty vehicles and 

from 700°C today to 900°C by 2050 in heavy-duty vehicles. 

Alloys that can withstand these temperature ranges are needed so that car manufacturers can produce 

vehicles with higher-efficiency engines employing modified internal combustion regimes. Use of such 

engines would improve the fuel economy of passenger vehicles by 25% and would improve the efficiency 

of commercial vehicle engines by at least 20%. Barriers to introducing new, high-performance material in 

these high-efficiency engines include the cost of existing high-performance alloys that can withstand the 

extreme conditions of downsized, turbocharged engines and the long lead times required for 

commercialization of new alloys.

ORNL has developed lower-cost, higher-strength nickel-based alloys that are capable of withstanding 

more extreme temperatures than the alloys currently used in exhaust valves (e.g., alloy 751). Use of the 

new alloys will enable higher efficiencies without incurring a significant cost penalty. The new alloys 

have been designed to contain up to 40% less Ni and to achieve high strength without the addition of 

other expensive alloying elements. They possess high strength and good oxidation resistance at 

temperatures up to 950°C. 

A computationally guided approach was used to develop this new class of lower-Ni alloys with higher 

strength at temperatures up to 950°C. A similar approach was used earlier to develop other cost-effective 

alloys for use at temperatures up to 870°C. Several experimental strategies to improve oxidation 

resistance in the 950°C alloys were also proposed and evaluated.

Oxidation was shown to lessen with the additions of trace amounts of reactive elements. Transmission 

electron microscopy and X-ray scattering is being used to understand the effect of precipitation on 

strengthening and will ultimately help in minimizing the levels of strengthening additions that can 

adversely affect oxidation resistance. Testing showed that changes in processing temperature favorably 

affected the ductility of alloys during industrial processing.

Experiments are on-going to understand the optimum process temperatures for industrial processing of 

the new ORNL alloys.

Publications, Presentations, and Patents

1. G. Muralidharan. “Computation-Aided Development of High Temperature Structural Alloys.” First 

International Symposium on Structural Materials for Innovation, February 26, 2015, Tokyo, Japan.
2015 Annual Report Vehicle Technologies R&D Highlights

ORNL Sustainable Transportation Program 77

ORNL’s nickel-based alloys can be used in exhaust valves and show high strength and good oxidation 

resistance at temperatures 950°C and above.

Novel In Situ Electron Microscopy Developed for Characterizing 

Catalyst Behavior Under “Real” Reaction Conditions

Contact: Lawrence F. Allard, allardLFjr@ornl.gov, 865-607-1144

ORNL collaborated with Protochips Inc., based in Raleigh, North Carolina, and led the development of a 

novel in situ reactor holder for electron microscopes. The reactor, called the Atmosphere 200, is a 

complete environmental gas cell that frees researchers from the confines of the transmission electron 

microscope vacuum.

Based on unique semiconductor technology, the Atmosphere 200 operates at up to 1 atm of pressure 

within a “closed-cell” specimen holder, while maintaining atomic resolution. It features ultralow-drift 

heating and automated closed-loop temperature control that can quickly reach and maintain temperatures 

of 1,000°C.

Through its novel design, evaluated through several generations of development at ORNL, the 

Atmosphere 200 is compatible with the most advanced spectroscopic systems and turns any electron 

microscope into a high-performance gas-reaction system, allowing scientists to explore the composition 

of materials at very small scales (nano to atomic) at elevated temperatures and at high pressures in gas 

environments. The device enables new research avenues, including in situ study of single-atom catalysts.

Publications, Presentations, and Patents

1. L. F. Allard et. al. “Novel MEMS-Based Gas-Cell Heating Specimen Holder Provides Advanced 

Imaging Capabilities for In Situ Reaction Studies.” Micros Micoranal 18(04), 2012, 656–666.
Vehicle Technologies R&D Highlights 2015 Annual Report

78 ORNL Sustainable Transportation Program

Researcher Larry Allard works with the Atmosphere 200 on ORNL’s JEOL 2200FS 

aberration-corrected electron microscope.

ORNL Develops Advanced Alloys for Turbochargers and Manifolds

Contact: Phillip J. Maziasz, maziaszpj@ornl.gov, (865) 574-5082

Automotive exhaust components, which experience temperatures as high as 950°C, require materials with 

better heat-resistance than current commercial SiMo or D5S cast irons. 

ORNL’s CF8C-Plus cast stainless steels with ~20Cr and 12Ni were developed for advanced diesel 

exhaust components and exhibited very good mechanical properties up to at least 850°C. CN12-Plus cast 

austenitic stainless steel had 25Cr, slightly increased Ni, and more C+N (0.8), resulting in better tensile 

and creep strength than most commercial austenitic alloys for applications up to 950°C.

CN12-Plus was scaled up to commercial heats in 2015. Tensile testing occurred up to 1000°C, and creeprupture evaluation occurred at 850°C to 950°C. Oxidation testing occurred in air+H2O at 850°C to 950°C.

CN12-Plus improved yield strength vs. CF8C-Plus and exhibited a better combination of yield strength 

and ductility than CN12-PlusCuW. CN12-Plus also provided a better base alloy matrix for modifying 

with aluminum additions to further improve oxidation resistance at 950°C.

Publications, Presentations, and Patents

1. None to report this period.
2015 Annual Report Vehicle Technologies R&D Highlights

ORNL Sustainable Transportation Program 79

Cast iron and austenitic stainless steel tensile properties at elevated temperatures.

ORNL, Industry Partners Use High-Performance Computing to Drive 

Alloy Design

Contact: Amit Shyam, shyama@ornl.gov, (865) 241-4841

A team of researchers from ORNL, FCA US LLC, and Nemak of Mexico used integrated computational 

materials engineering (ICME) to speed the development of affordable new high-temperature aluminum 

alloys for automotive cylinder heads. ICME enabled researchers to tailor new alloys at the atomic level to 

achieve desired properties such as strength and ease of manufacture.

The project is focused on engineering a material that is 25% stronger than current alloys and durable at 

temperatures 50°C higher than existing baseline alloys, a necessity for next-generation engines. The real 

challenge is to accomplish this while keeping costs low for automotive manufacturers and consumers.

ORNL broke new ground by scaling ICME to run on DOE’s Titan supercomputer, the second-fastest 

computer in the world. Using Titan’s speed and parallel-processing power, ORNL researchers 

predictively modeled new alloys and selected only the best candidates for further experimentation. This 

predictive capability dramatically reduced the time, energy, and resources devoted to casting trial alloys.
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80 ORNL Sustainable Transportation Program

Before the shift to Titan, a Linux cluster was used with approximately 300 cores creating atomistic 

simulations of single elements diffusing to intermetallic precipitates within the alloy. Researchers 

achieved larger-scale simulations on Titan that are much closer to real-world scenarios.

The team verified the computational models through atomic-scale imaging and analytical chemistry 

measurements. ORNL’s scanning transmission electron microscopy and atom probe tomography allowed 

researchers to identify and examine the location and chemistry of each atom in the alloy matrix, the 

precipitates, and the interfaces between them.

ORNL and collaborators also created a database capturing their aluminum alloy materials discoveries. 

This “materials genome” approach helped guide efforts to improve ICME capabilities and accelerated the 

development of new high-performance materials.

Publications, Presentations, and Patents

1. A. Sabau, W. Porter, R. Shibayan, and A. Shyam. “Process Simulation Role in the Development of 

New Alloys Based on an Integrated Computational Materials Engineering Approach.” AMSE 2014 

International Mechanical Engineering Congress & Exposition, November 14–0, 2014, Montreal, 

Quebec, Canada

A team of researchers led by ORNL’s Amit Shyam is using 

high-performance computing to speed the development of 

new high-temperature aluminum alloys for automotive 

cylinder heads.
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ORNL Sustainable Transportation Program 81

Vehicle Systems

Advanced Combustion and Emission Control Technology Analysis and 

Evaluation

Contact: Zhiming Gao, gaoz@ornl.gov, 865-946-1339

To meet 2025 Corporate Average Fuel Economy standards, EPA Tier III emissions regulations, and 

Renewable Fuel Standard requirements will require integration of numerous advanced technologies such 

as high-efficiency clean combustion engines, leading-edge catalysts, and renewable fuels. That integration 

will require a deep understanding of the complex processes involved, fostered not only by 

experimentation, but also by analysis, modeling, and simulation. 

The goal of this project is to assist with this process by providing comprehensive vehicle system 

simulations that support DOE R&D efforts in evaluating and identifying innovative technologies and to 

leverage activities that will assist US automakers in meeting future fuel economy standards and emissions 

regulations. The models and simulations developed as part of this program rely on measurements from 

multiple facilities at ORNL and can be implemented directly in simulation platforms such as Autonomie. 

These models also provide guidance to experimental teams in targeting future measurements. This close 

interaction between simulation and experimentation provides DOE with the best possible basis for 

identifying promising vehicle technologies that maximize energy efficiency and minimize any negative 

environmental impacts from transportation.

In FY 2015 the project team continued to collaborate with partners at ORNL; in the DOE Advanced 

Combustion Engine, Fuel and Lubricant Technologies, and Vehicle Systems Simulation and Testing 

Programs; and in various other research programs to evaluate and identify the impacts of multiple 

reactivity-controlled compression ignition (RCCI) regimes on fuel economy and emissions from 

conventional and hybrid vehicles. 

Two sets of new engine maps were constructed for 1.9 L GM engines enabled with mixed-mode 

operation between conventional diesel combustion (CDC) and RCCI and for a Ford EcoBoost 1.6 L 

turbocharged gasoline direct injection engine. Simulation results indicate that this RCCI implementation 

can boost fuel economy by nearly 30% compared to port fuel injection (PFI), which is consistent with the 

DOE FY 2015 Joule milestone.

Comparison of various RCCI fueling strategies was also carried out in conventional and hybrid vehicles. 

Results indicate renewable fuels such as E30 and B20 are capable of extending the RCCI operating 

regime and enhancing engine efficiency over city and highway driving cycles. The results also indicate 

that actual fuel economies of RCCIs are substantially higher than PFI gasoline, but differ little from CDC 

fuel economy levels. 

A one-dimensional diesel oxidation catalyst (DOC) model that uses a new global kinetic reaction 

mechanism was developed, refined, and validated. The model accounts for CO, hydrocarbon, and nitrous 

oxide oxidation for CDC and RCCI exhausts during cold-start and the transition to mixed-mode operation 

and has been used in exploring sophisticated RCCI utilization strategies. The simulated results show that 

RCCI utilization strategies that manage CDC–RCCI switches via regulating exhaust temperature could 

significantly improve the performance of conventional DOCs during transient drive cycles involved in 

RCCI utilization.
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82 ORNL Sustainable Transportation Program

(b)

Example of steady-state engine maps for (a) the 1.9 L GM engine with the RCCI-enabled zone 

highlighted and (b) the 1.6 L Ford turbocharged gasoline direct injection (GDI) stoichiometric engine. 

The pink circles in (a) indicate measured reactivity-controlled compression ignition operating 

conditions.

Publications, Presentations, and Patents

1. Z. Gao, S. Curran, J. E. Parks, D. E. Smith, et al. 2015. “Drive Cycle Simulation of High Efficiency 

Combustions on Fuel Economy and Exhaust Properties in Light-Duty Vehicles.” Applied Energy 157: 

762–776 (invited).

2. Z. Gao, D. E. Smith, C. S. Daw, K. D. Edwards, et al. 2015. “The Evaluation of Developing Vehicle 

Technologies on the Fuel Economy of Long-Haul Trucks.” Energy Conversion and Management 106: 

766–781.

3. S. Curran, Z. Gao, and R. M. Wagner. 2015. “Reactivity-Controlled Compression Ignition Drive 

Cycle Emissions and Fuel Economy Estimations Using Vehicle System Simulations.” International 

Journal of Engine Research 16: 1013–1024.

4. Z. Gao, S. Curran, C. S. Daw, D. E. Smith, and J. E. Parks. 2015. “Comparison of the Simulated 

Light-Duty Drive-Cycle Fuel Economy and Engine Exhaust Properties for Three Different RCCI Fuel 

Combinations.” presented at the 9th US Combustion Meeting, May 2015. 

5. S. Curran, Z. Gao, D. E. Smith, and C. S. Daw. 2015. “Impacts of Advanced Combustion Engines.” 

presented at the 2015 DOE Hydrogen Program and Vehicle Technologies Program Annual Merit 

Review and Peer Evaluation Meeting, June 9, 2015. 
2015 Annual Report Vehicle Technologies R&D Highlights

ORNL Sustainable Transportation Program 83

Fleet DNA Database Development and Support

Contact: Oscar Franzese, franzeseo@ornl.gov, 865-946-1304

A lot of information on medium and heavy truck real-world duty cycles (MTDCs and HTDCs) has been 

generated by ORNL as part of DOE-sponsored projects. Other DOE laboratories, various state and federal 

agencies, and private industry [original equipment manufacturers (OEMs) and fleets] have also generated 

duty cycle information, although not as extensively as the DOE MTDC and HTDC projects. The problem is 

that the data are in multiple locations, in multiple formats, with no common means of access. With this in 

mind, in 2012 the Vehicle Systems Simulation and Testing (VSST) project within the DOE Vehicle 

Technologies Office funded the Fleet DNA project to provide a common location for storage and basic 

analysis of this type of information. ORNL and the National Renewable Energy Laboratory (NREL), 

VSST’s primary medium- and heavy-duty truck data collection laboratories, were authorized to assemble 

previously collected data in a common database (Fleet DNA); develop data analysis and access techniques 

to make the data available to OEMs, fleets, and others; and develop methods for collection and processing 

of future data from various organizations.

During the first phase of this project, ORNL worked with NREL to merge the existing ORNL MTDC and 

HTDC databases into the Fleet DNA data repository at NREL in accordance with project guidelines. The 

data were parsed, and selected channels were extracted and filtered using different techniques and 

methods developed exclusively for this project. This work generated the base Fleet DNA database, which 

covers specific vocations, long-haul operations, regional delivery, public transit (buses), electrical utility 

vehicles, and tow and recovery vehicles. 

Sample Fleet DNA database information. This graph shows the relationship between daily average 

driving speed and kinetic intensity, which is a measure of how a vehicle drives, starts, and stops. High 

kinetic intensity means the vehicle starts and stops often during its route. Low kinetic intensity means 

the vehicle does not start and stop as often. A vehicle with high kinetic intensity and low-speed is a 

good candidate for hybridization because the regenerative brakes charge the battery effectively. [Fleet 

DNA project data courtesy of the Fleet DNA database, http://www.nrel.gov/fleetdna.]

In the second phase of the project, completed in 2015, ORNL developed methods and algorithms to build 

searching tools that would allow extraction of information from the ORNL Fleet DNA database duty 

cycles based on user-defined criteria.
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84 ORNL Sustainable Transportation Program

This and future efforts will provide OEMs and fleets, other DOE programs, and other federal agencies 

with valuable drive cycle information to make decisions about and deploy and design advanced 

technology vehicles.

Publications, Presentations, and Patents

None to report this period.

MD and HD Accessory Hybridization for Fuel Savings and Emissions 

Control

Contact: Dean D. Deter, deterdd@ornl.gov, 865-576-8620

Medium-duty (MD) and heavy-duty (HD) trucks, used for home delivery of goods and HD freight 

hauling, are the main means by which material and goods are transported in the United States and might 

justifiably be called the workhorses of our society. Modern trucks have become much more advanced in 

terms of engine, aftertreatment, and transmission technologies, which have greatly reduced both fuel 

consumption and emissions. However, HD line haul trucks, which account for about 20% of total US 

truck fuel use, often idle for long periods in traffic and overnight for “hotel loads,” which include cab 

cooling and power for things such as televisions, refrigerators, and phone chargers. This causes 

unnecessary amounts of fuel to be burned and releases additional emissions into the atmosphere. 

A unique cooperative research and development agreement between ORNL and Cummins, a global leader 

in the design, manufacture, and distribution of diesel and natural gas engines and related components, 

seeks to address this problem and in so doing reduce fuel consumption and emissions. An ancillary goal 

for ORNL was determining which technologies would be most readily accepted by fleet owners and 

industry. Using ORNL’s Vehicle Systems Integration (VSI) Laboratory, the team was able to test 

prototypes at both component and systems levels for initial development and validation, which was 

quicker, safer, and more cost effective than using a test vehicle. 

Line haul drivers are required to spend 10 hours’ down time between each haul (typically overnight). 

During down time, the truck will idle during the night’s hotel stay (8 to 10 hours) and will use 4 to 7 gal 

of diesel fuel if the driver needs air conditioning or power for phone chargers, TV, radio, etc. That does 

not account for time spent idling when trucks are preparing to load or unload cargo or sitting in traffic.

Currently, idle mitigation is handled with auxiliary power units (APUs), but they are generally 

aftermarket units that are added rather than built into the original truck systems, so they are not maximally 

efficient and in some cases contribute to maintenance issues. In addition, the units are only advantageous 

when trucks are not running.

The ORNL-Cummins proposed solution will be an integrated system that will allow elimination of 

overnight idling, connectivity with shore power, engine start/stop capability, optimized cooling capacity 

via electric fans, and regenerative braking. The prototype APU system is currently undergoing testing in a 

Cummins test vehicle. 

When the project was initiated, physics-based MD and HD accessories models—for such things as air 

conditioning, power steering, fans, and pumps— were not available, so among the first things researchers had 

to do were to collect data on all accessories and to develop physics-based mechanical and electrical accessory 

models, which were then integrated into vehicle models. After air conditioning became a focal point of the 

study, the National Renewable Energy Laboratory’s CoolSim modeling tool was adopted to provide a highfidelity physics-based air conditioning model for validation of the conventional and prototype systems. The 

model will be validated and updated using data from this project for use in future projects.
2015 Annual Report Vehicle Technologies R&D Highlights

ORNL Sustainable Transportation Program 85

ORNL VSI Component Test Cell. Using ORNL’s Vehicle 

Systems Integration Laboratory, testing prototypes at 

both a component and powertrain level instead of 

using a test vehicle, allows for quicker, safer, and 

more cost-effective development and validation.

Publications, Presentations, and Patents

1. M. M. Kumar, G. L. Parker, S. Varigonda, J. E. Paquette, B. D. Padgett, W. B. Fields, P. C. Mualidhar, 

V. A. Sujan, D. D. Deter, and D. E. Smith. Apparatus and System for Controlling Power to an Air 

Conditioning Compressor for a Vehicle. US Patent Application 62/354,364, filed June 24, 2016.

ORNL Collecting Important Data on Electric Vehicle Charging

Contact: Melissa Lapsa, lapsamv@ornl.gov, 865-576-8620

Widespread electric vehicle (EV) use is such a recent phenomenon that statistics on factors of interest 

such as recharging patterns, peak times of recharging station use, and optimal placement of charging 

stations are needed. Such factors are important to developing the charging infrastructure necessary to help 

power a sustainable transportation future.

Thanks to the 2009 DOE American Recovery and Reinvestment Act, related ECOtality grants, and 

regional cost-share investments, ORNL has been able to explore these factors in greater detail. The 

original project, which at the time was the largest deployment of EVs and charging infrastructure in 

history, allowed for the deployment of more than 15,000 charging systems (solar- and non-solar-powered) 

to support EVs in strategic markets in six states (Arizona, California, Oregon, Tennessee, Texas, and 

Washington) and Washington, DC. One of the goals of the original project was to collect and analyze data 

to characterize EV use under diverse topographic and climatic conditions. 

The original project ended in FY 2014, but in 2015 ORNL received additional DOE funding to continue 

collecting, analyzing, and reporting EV charging data for Tennessee, specifically the 44 charging stations 

(solar and nonsolar) at ORNL and, to the degree possible, solar-assisted installations across the state. 

(Note: Since completion of the original project, data on some of the charging stations across the state are 

no longer available.)
Vehicle Technologies R&D Highlights 2015 Annual Report

86 ORNL Sustainable Transportation Program

Major areas for tracking and analysis have been 

energy consumption, times of connect and 

disconnect, duration of charging, and overall use 

of the stations. Energy consumption and duration 

of charging provide insights on the state of charge 

of car batteries at the start of charging and the 

associated recharging patterns. Connect and 

disconnect times provide information on peak 

times of station use and, again, recharging 

patterns at ORNL and in public settings. The 

insights gained will be useful in determining the 

need for and locations of additional stations at 

ORNL and elsewhere in the state.

Findings

The following are among the findings so far.

1. At ORNL, the distributed charging stations (i.e., those located near major office areas) have higher

use rates than the centrally located stations.

2. Based on monthly power consumption for EVs charging at ORNL, it is estimated that fuel savings 

exceed 700 gal of gasoline each month.

3. Use at most of the ORNL-installed EV charging station sites has increased rather steadily since they 

were first installed—something that would be expected with greater familiarity with the sites over 

time and the growing number of EVs on the site. 

4. Longer use data are needed to draw additional conclusions about statewide use trends, and this work 

is continuing in 2016.

Publications, Presentations, and Patents

None to report this period.

Powertrain Controls Optimization for Heavy-Duty Hybrid Line Haul 

Trucks

Contact: David E. Smith, smithde@ornl.gov, 865-946-1324

Hybrid medium- and heavy-duty powertrains have great potential for reductions in fuel consumption, 

criteria pollutants, and greenhouse gases through integrated diesel hybridization, analytical modeling, 

regenerative braking, hybrid energy storage, and supervisory controls development. This project seeks to 

leverage advances in these multiple research areas on a single vehicle platform. In addition, advanced 

combustion technologies such as reactivity-controlled compression ignition will be implemented into an 

advanced hybrid powertrain for a Class 8 line haul application.

There are four focus areas for the project, ranging from advanced combustion regimes and engine control 

strategies to emissions control technologies, pulsed energy storage systems (dual energy storage systems), 

and advanced energy management and supervisory controls.

In 2015, progress was made in the following areas.

Electric cars plugged in at the ORNL solar-charging 

facility. 
2015 Annual Report Vehicle Technologies R&D Highlights

ORNL Sustainable Transportation Program 87

• Engines and emissions data. Engine fuel consumption and emissions data were enhanced by 

leveraging other ongoing projects in the ORNL Vehicle Systems Integration (VSI) Laboratory. A 

complete test matrix was executed (and repeated for accuracy) for developing more reliable engine 

and emissions data. Fuel consumption data were verified through comparison of actual fuel 

measurement, J1939 engine network data, and emission/air fuel calculations.

• Engine system models. ORNL has implemented past transient engine modeling experience to 

develop a transient model for use in Autonomie of a Cummins ISX-450 15 L engine and an 

associated emissions aftertreatment system. Emphasis was placed on completing development and 

validation of the aftertreatment models for this powertrain in FY 2015. Data were logged from the 

actual components in the ORNL VSI Laboratory and were used to validate the resulting empirical 

models over a host of drive cycles.

• Hybrid energy storage system. The simulation model for the dual energy storage system has been 

completed, including voltage mode control of boosting and buck modes and the addition of an 

ultracapacitor parameter extraction tool that, given an appropriate single-pulse-discharge data set, 

facilitates voltage-dependent modeling of any manufacturer’s ultracapacitor.

The project is being refocused in FY 2016 to align research more closely with 21st Century Truck 

Partnership needs, which will include powertrain optimization of conventional line haul vehicles through 

controls integration and optimization of both the engine and the transmission.

Publications, Presentations, and Patents

None to report this period.

Researchers leveraged experimental powertrain results 

from the ORNL Vehicle Systems Integration Laboratory to 

complete enhanced engine and aftertreatment models for 

this project.
Vehicle Technologies R&D Highlights 2015 Annual Report

88 ORNL Sustainable Transportation Program

Vehicle Technologies Office Communications

ORNL Publications Support Outreach Efforts and Meet Data Needs of 

the DOE Vehicle Technologies Office

Contact: Stacy Davis, davissc@ornl.gov, 865-946-1256

ORNL continued to support the DOE Vehicle Technologies Office (VTO) public communication efforts 

in 2015 with publication of the Transportation Energy Data Book, the Vehicle Technologies Market 

Report, and the “Fact of the Week” for the VTO home page.

The Transportation Energy Data Book (TEDB), published in 

September, is the 34th edition of the data collection that ORNL 

publishes for VTO. This long-running project has been active at 

ORNL since 1975; the first edition was published in 1976. The 

TEDB website (http://cta.ornl.gov/data/index.shtml) allows 

visitors to download TEDB in pdf format, download any of the 

Excel spreadsheets in the book individually, or request a hard 

copy of the report free of charge. Between 6,000 and 8,000 visits 

to the website are logged each month. In addition, TEDB was 

printed and distributed to a nationwide mailing list.

The document supports VTO public outreach, allowing VTO staff 

to provide quick responses to queries on transportation energy 

use. The goal is to produce a comprehensive document with 

transportation data from diverse sources for use in answering 

transportation energy questions and resolving data conflicts and 

inconsistencies.

TEDB’s historical data tables provide a foundation for the 

analyses performed by VTO staff and other transportation analysts in pursuit of energy-efficient and 

environmentally friendly technologies. Policymakers, transportation analysts, and VTO staff require 

quality historical data and information on 

the transportation sector to make decisions 

for the future. Data from the book feed into 

many VTO products as well as into other 

federal agency projects.

The 2015 Vehicle Technologies Market 

Report was the sixth edition published by 

ORNL. It supports VTO public outreach by 

providing information on vehicle research to 

the public and meets internal VTO needs for 

data. The colorful, graphics-based report 

details major trends in US light duty vehicle 

and medium/heavy truck markets and 

provides data on an individual manufacturer 

level. Special attention is given to the 

progress of high-efficiency and alternative 

fuel technologies, in accordance with VTO’s 
2015 Annual Report Vehicle Technologies R&D Highlights

ORNL Sustainable Transportation Program 89

mission. The associated website (http://cta.ornl.gov/vtmarketreport) allows users access to data in both 

Excel and pdf format and hosts about 3,700 visitor sessions each month.

ORNL began developing the VTO “Fact of the 

Week” in April 2001 and continues to be 

responsible for the content each week. Every 

Monday morning, ORNL’s Sustainable 

Transportation Program provides a new Fact of the 

Week for the VTO home page 

(http://energy.gov/eere/vehicles/transportation-factweek). The topics align with the VTO mission, 

mainly concentrating on energy use and energy 

efficiency in highway driving mode. Transportation 

stakeholders and the general public benefit from 

VTO’s data expertise through these readily 

accessible bits of information. In 2015, the site 

allowed users to subscribe to receive an email every

Monday with the weekly fact. In the first 6 months, 

more than 1,300 people subscribed.