2011Annual Report

 Sustainable 

Transportation Program

 Sustainable 

Transportation Program

ORNL/TM-2012/196
Sustainable Transportation Program • OAK RIDGE NATIONAL LABORATORY

Prepared by

OAK RIDGE NATIONAL LABORATORY

Oak Ridge, Tennessee

managed by 

UT-BATTELLE, LLC

for the 

U.S. DEPARTMENT OF ENERGY

under contract DE-AC05-00OR22725

This document highlights work sponsored by agencies of the U.S. Government. Neither the 

U.S. Government nor any agency thereof, nor any of their employees, makes any warranty, 

express or implied, or assumes any legal liability or responsibility for the accuracy, completeness, or usefulness of any information, apparatus, product, process disclosed, or represents 

that its use would not infringe privately owned rights. Reference herein to any specific commercial product, process, or service by trade name, trademark, manufacturer, or otherwise 

does not necessarily constitute or imply its endorsement, recommendation, or favori ng by 

the U.S. Government or any agency thereof. The views and opinions of authors expressed 

herein do not necessarily state or reflect those of the U.S. Government or any agency thereof.

ORNL 2012-G00334-lam
2011

Annual Report

 Sustainable 

Transportation 

 Program
Sustainable Transportation Program • OAK RIDGE NATIONAL LABORATORY
Sustainable Transportation Program • OAK RIDGE NATIONAL LABORATORY

Introduction 6

Program Support...........................................................................................................8

Facilities.......................................................................................................................10

Patents and Invention Disclosures................................................................................14

Awards and Professional Honors..................................................................................15

Publications and Presentations....................................................................................19

Biomass R&D Highlights 23

Billion Ton Update........................................................................................................24

The Bioenergy Knowledge Discovery Framework............................................................26

Ethanol Blends Materials Compatibility Study Released................................................28

Biomass Supply Chain Modeling and Analysis..............................................................30

Sustainability of Biomass Production...........................................................................32

Department of Transportation R&D Highlights 35

Smart Roadside Initiative for Commercial Vehicle OperationsWireless Roadside Inspection.......................................................................................36

Development of a Supply Chain–Based Fuel Tax Evasion Detection System..................38

National Intelligent Transportation Systems Deployment Survey...................................40

New Method for Estimating Fuel Economy by Vehicle Class..........................................42

Hydrogen and Fuel Cell Technologies R&D Highlights 45

Reducing the Production Cost of High Strength Carbon Fibers for

Hydrogen Storage........................................................................................................46

Investigating Aging an Associated Degradation of Membrane Electrode

Assemblies for Proton Exchange Membrane Fuel Cells..................................................48

Vessel Design and Fabrication Technology for Stationary High-Pressure

Hydrogen Storage.........................................................................................................50

Vehicle Technologies R&D Highlights 53

Policy Analysis.............................................................................................................54

Combustion Engines.....................................................................................................56

Energy Storage.............................................................................................................62

Fuels............................................................................................................................70

High Temperature Materials Laboratory........................................................................78

Lightweight Materials...................................................................................................90

Propulsion System Materials......................................................................................100

Power Electronics and Electric Machines....................................................................106

Vehicle and Systems Simulation and Integration.........................................................112

Table of Contents
Sustainable Transportation Program • OAK RIDGE NATIONAL LABORATORY

Introduction

6
Sustainable Transportation Program • OAK RIDGE NATIONAL LABORATORY

Introduction

7

ORNL’s Sustainable Transportation 

Program performs research and development leading to new vehicle and transportation system technologies. Highway 

transportation—light-, medium-, and 

heavy-duty vehicles—accounted for approximately 23% of U.S. greenhouse gas 

emissions and about 64% of all petroleum used in the United States in 20091

. 

Energy use in highway transportation 

is expected to increase almost 21% by 

2035—from 11.1 to 13.4 million barrels 

per day oil equivalent2. ORNL researchers are focusing on clean, efficient, and 

intelligent paths to reducing transportation fuel consumption and emissions, 

and achieving improved energy security. 

The research and development portfolio 

includes alternative fuels, more efficient 

vehicle components, lightweight materials, transportation electrification, and 

intelligent transportation systems and 

operations. 

The Program’s primary support comes 

from the Department of Energy, Office of 

Energy Efficiency and Renewable Energy, 

through three technology development 

programs: Vehicle Technologies, Fuel Cell 

Technologies, and Biomass Programs. 

Support also comes from the Department 

of Transportation, other federal agencies, 

and the private sector. 

Support of the Vehicle Technologies 

Program was highlighted by achievement 

of the U.S. DRIVE Partnership3 engine 

efficiency goal, use of neutron imaging techniques to study emission control 

devices and lithium distribution in battery 

electrodes, and advancing electric vehicle 

charging technologies including solarassisted charging and wireless charging. 

Researchers are investigating innovative 

electric motor designs that reduce or 

eliminate the need for rare-earth permanent magnets, which are subject to market 

fluctuations in availability and cost. 

ORNL has worked with the Fuel Cell Technologies Program for several years on a 

nitrided material for use in fuel cell bipolar 

plates. In FY 2011, a collaborative effort 

with General Motors to explore manufacturability of the material by GM’s exist1 Davis, S. C., S. W. Diegel and R. W. Boundy. 2011. Tables 1.12, 1.13, 11.3, 11.7 in Transportation Energy Data 

Book, Edition 30. ORNL-6986, Oak Ridge National Laboratory, Oak Ridge, Tennessee.

2 U.S. Energy Information Administration. 2011. Table A7 in Annual Energy Outlook 2011 With Projections to 

2035. U.S. Department of Energy, Washington, D.C.

3 Formerly the FreedomCAR and Fuel Partnership, U.S. DRIVE is a non-binding and voluntary governmentindustry partnership focused on advanced automotive and related infrastructure technology research and 

development. 
Sustainable Transportation Program • OAK RIDGE NATIONAL LABORATORY

Introduction

8

ing stamping and welding practices was 

successful. A new multiyear project began 

to develop a stationary hydrogen storage 

system; preliminary engineering design 

has demonstrated that the integrated steel 

and prestressed concrete storage vessel 

can sustain 5,000 psi pressure based on 

industry codes and standards. 

In Biomass Program support, researchers 

launched the Bioenergy Knowledge Discovery Framework, a computational tool 

for data visualization and analysis. Staff 

completed and issued an update to the 

2005 “Billion Ton Study” that confirmed 

the technical feasibility of U.S. lands 

supplying a billion tons of dry biomass 

annually, while giving increased attention 

to environmental sustainability and landuse change4

. A widely cited study5 using 

empirical data found that indirect land use 

change resulting from expanded corn ethanol production over the past decade has 

been minimal. ORNL completed a threeyear study measuring critical property 

changes for classes of fuel dispenser materials exposed to ethanol-blended fluids6

. 

The test results are intended to be used to 

identify potential issues and guide the 

selection and development of materials 

compatible for use in E15 dispensers.

The Sustainable Transportation Program 

continued to provide outstanding support to the Department of Transportation, enhancing data quality and developing on-line analysis tools for the 2009 

National Household Travel Survey data 

and Freight Analysis Framework, the 

most comprehensive publicly available 

data sets on personal and freight movement in the United States. The Federal 

Motor Carrier Safety Administration reaffirmed their multi-year commitment to 

the Commercial Motor Vehicle Roadside 

Testing Corridor, stating that ORNL had 

demonstrated the capability to take care 

of all their roadside-based testing needs. 

Highlights of selected Program research 

and development efforts begin on page 

23. 

4 U. S. Department of Energy. 2011. U.S. Billion-Ton Update: Biomass Supply for a Bioenergy and Bioproducts 

Industry. R.D. Perlack and B.J. Stokes (Study Leads), ORNL/TM-2011/224. Oak Ridge National Laboratory, 

Oak Ridge, Tennessee.

5 Oladosu, G., and K. L. Klein. 2010. “Decomposition analysis of U.S. corn use for ethanol production 

from 2001-2008.” Presented at California Air Resources Board (CARB) Low Carbon Fuel Standard Expert 

Workgroup Meeting, Sacramento, Calif., October 14–15.

6 Kass, M., et al. 2011. Intermediate Ethanol Blends Infrastructure Materials and Compatibility Study: Elastomers, 

Metals, and Sealants. ORNL/TM-2010/326. Oak Ridge National Laboratory, Oak Ridge, Tennessee. 
Sustainable Transportation Program • OAK RIDGE NATIONAL LABORATORY

Introduction

9

Program Support

The Program received $73.4M in new funding 

in FY 2011 with the largest portion being from 

the Vehicle Technologies Program. 

About half of the Program’s R&D is conducted at the National Transportation 

Research Center (NTRC) located in Knoxville, Tennessee. Since 2002, the NTRC has 

benefited from a reduced overhead rate 

by virtue of being located off the ORNL 

From FY 2002 through FY 2011, cumulative overhead savings of $11.9M have been applied 

to research and development projects at the NTRC due to its off-campus location. 

main campus. The figure below shows the 

approximate annual and cumulative cost 

savings resulting from NTRC’s off-site location. In FY 2012, the ORNL cost model will 

change and NTRC will no longer be considered “off site” for overhead purposes. 
Sustainable Transportation Program • OAK RIDGE NATIONAL LABORATORY

Introduction

10

Facilities

Establishing, upgrading, and maintaining 

facilities and experimental capabilities is 

a key element of the Program’s support 

for its sponsors. In FY 2011, the Program 

expanded capabilities and launched new 

facilities to support R&D programs in 

materials, advanced combustion, energy 

storage, vehicle systems, power electronics, hydrogen, and analysis. 

Lightweight Materials. The Program’s largest infrastructure project is 

the Carbon Fiber Technology Facility, 

funded in late 2009 as part of the American Recovery and Reinvestment Act. This 

$34,700,000 facility will house systems 

capable of producing semi-production 

quantities (up to 25 tons per year) of lowcost carbon fiber sufficient to make largescale material and process evaluations. 

The highly flexible facility will be capable 

of handling multiple precursor chemistries 

Layout of the Carbon Fiber Technology Facility 

production area.

and material formats. It will house a melt 

spun precursor fiber semi-production line 

and conventional fiber conversion technologies, and will accommodate advanced 

conversion technologies as they mature. 

The Carbon Fiber Technology Facility is 

scheduled to be operational in 2013. 

A critical link in scaling technologies from 

lab scale to the Carbon Fiber Technology Facility, ORNL’s conventional Carbon 

Fiber Pilot Line is getting a significant 

upgrade to enhance throughput, controls, 

and flexibility, and integrate carbonization 

and oxidation capabilities with the Precursor Evaluation System. The upgraded 

Pilot Line will be capable of producing 12 

pounds of fiber per day as compared to 

the current 2 pounds per day. Tension control will be significantly enhanced, as will 

surface treatment, sizing, control system, 

and data acquisition capabilities. 
Sustainable Transportation Program • OAK RIDGE NATIONAL LABORATORY

Introduction

11

NTRC-2. ORNL has leased a newly 

constructed building adjacent to the 

NTRC to provide additional office space 

and laboratories for the Sustainable 

Transportation Program. New capabilities housed in NTRC-2 include the Vehicle 

Systems Integration Laboratory, Battery 

Cell Manufacturing Facility, and Transportation Analysis and Visualization Laboratory.

Vehicle Systems Integration 

Laboratory. The Vehicle Systems 

Integration Laboratory will enable fully 

integrated, system-level research on 

advanced combustion, electric drivetrain, 

controls, and fuel technologies. It will 

allow researchers to study complex 

interactions of advanced prototype 

technologies to achieve maximum 

efficiency with lowest possible emissions. 

Equipped for light-, medium-, and heavyduty powertrain architectures, the VSI lab 

will facilitate understanding of advanced 

transportation technologies operating 

under real-world conditions. The 

laboratory is scheduled to be operational 

in summer 2012. 

Battery Cell Manufacturing Facility.

A battery cell manufacturing facility will 

focus on developing and refining new 

technologies for materials processing 

and battery assembly to reduce scrap 

rate, increase production speeds, and 

improve battery performance. This 

facility is scheduled to be operational in 

spring 2012. 

Transportation Analysis and 

Visualization Laboratory (TRAVL).

TRAVL features a 15-panel highdefinition video wall that accommodates 

simultaneous display of up to 30 

high-definition video content sources. 

With processing power for multi-HD 

3D graphics, the system supports the 

most advanced real-time simulation 

and modeling collaborations. Future 

TRAVL projects will include visualizing 

freight on highway, rail and waterways 

systems; large scale truck tracking to 

assess energy efficiency and safety; 

and integrating geo-visualization with 

human factors research. 
Sustainable Transportation Program • OAK RIDGE NATIONAL LABORATORY

Introduction

12

Power Electronics and Electric 

Machines. A state-of-the-art laboratory 

was created to support investigation of 

innovative materials, structures, and processing of the power electronics module, 

or PEM. The PEM plays a large role in the 

operation of electric vehicles. Advanced 

PEMs can offer superior performance, 

thermal management, and power density. 

The automated test facility for performance characterization of wide bandgap 

semiconductors was upgraded: throughput and detail have been improved, 

characterization costs have been lowered, 

and high switching frequency of gallium 

nitride devices is now accommodated. 

Advanced Combustion and 

Fuels. The air handling system was 

upgraded on the flexible single-cylinder 

research engine. The upgraded air 

handling system will allow research to 

expand the high load limits of advanced 

combustion, and will support research 

into pre-ignition phenomena in boosted 

spark ignition conditions (for example, 

superknock).

High Temperature Materials 

Laboratory. A specialized in situ gas 

flow holder was developed for the aberration-corrected scanning transmission 

electron microscope. The holder allows 

for the observation of catalysts in the 

presence of a gas at pressures up to 1 atmosphere and temperatures up to 1200°C 

with sub-nanometer-scale spatial resolution. This new technology will enable a 

number of unique experiments involving 

real-time observation of catalyst sintering, 

coarsening, phase transformations, and 

so forth.

Fuel Cell Technologies. An 

electron energy loss spectrometer was 

installed on an ORNL transmission/scanning transmission electron microscope, 

which has been used to characterize 

carbon corrosion mechanisms in polymer 

electrolyte membrane (PEM) fuel cell 

membrane electrode assemblies, and 

ionomer structure and chemistry in PEM 

fuel cell electrodes. The energy dispersive 

spectroscopy system on the microscope 

was upgraded with a silicon drift detector 

for rapid elemental data acquisition for 

compositional analysis. 
Sustainable Transportation Program • OAK RIDGE NATIONAL LABORATORY

Introduction

13

A new hydrogen charging system capable 

of maintaining or varying hydrogen pressure up to 10,000 psi has been designed 

and is being assembled. Combining the 

existing tensile and fracture toughness 

testing load-frames with a new fatigue 

testing load-frame under development 

in a collaborative project sponsored by 

the Department of Transportation, the 

upgraded testing facility will enable the 

comprehensive study of the effect of 

hydrogen on material properties under 

very high pressures that are relevant to 

hydrogen production, delivery, and storage infrastructure.
Sustainable Transportation Program • OAK RIDGE NATIONAL LABORATORY

Introduction

14

Patents and Invention 

Disclosures

Sustainable Transportation Program researchers submitted 44 invention disclosures resulting 

from efforts funded by the Vehicle Technologies 

Program and the Fuel Cell Technologies Program. Another 17 invention disclosures were 

filed in related efforts leveraged by funding from 

other federal agencies, industry, and ORNL 

strategic investments such as the Laboratory 

Directed Research and Development Program. 

Of these 61 invention disclosures, 18 were 

elected for patent filings, and 38 are still under 

consideration. 

Lightweight, Durable Lead-Acid Batteries. U.S. Patent No. 8,017,273. Inventors: Edgar 

Lara-Curzio, Ke An, James O. Kiggans, Jr., Nancy Dudney, Cristian Contescu, Frederick S. 

Baker, and Beth L. Armstrong. 

Utilization of Rotor Kinetic Energy Storage for Hybrid Vehicles. U.S. Patent No. 7,936,076. 

Inventor: John S. Hsu.

Self-Learning Control System For Plug-In Hybrid Vehicles. U.S. Patent No. 7,849,944. Inventor: Robert C. DeVault.

Laser-Induced Fluorescence Fiber Optic Probe Measurement Of Oil Dilution By Fuel. U.S. Patent No. 7,839,492. Inventors: James E. Parks, II and William P. Partridge, Jr. 

System To Continuously Produce Carbon Fiber Via Microwave Assisted Plasma Processing. 

U.S. Patent No. 7,824,495. Inventors: Terry L. White, Felix L. Paulauskas, and Timothy S. 

Bigelow. 

Iron-Based Alloy And Nitridation Treatment For PEM Fuel Cell Bipolar Plates. U.S. Patent No. 

7,829,194. Inventors: Michael P. Brady, Bing Yang, and Philip J. Maziasz.

During FY 2011, six patents were awarded based on previous filings.
Sustainable Transportation Program • OAK RIDGE NATIONAL LABORATORY

Introduction

15

Awards and Professional Honors

Research staff members received numerous awards and professional recognitions, reflecting significant contributions 

to research and technology development. 

Hydrogen sensor R&D funded by the 

Fuel Cell Technologies program won an 

R&D 100 award. A fuel-in-oil diagnostic 

technique developed under a Cooperative 

Research and Development Agreement 

with Cummins won a Federal Laboratory 

Consortium Excellence in Technology 

Transfer award. Four researchers received 

Outstanding Mentor Awards from the DOE 

Office of Science in recognition of outstanding contributions and dedication in 

mentoring. Program researchers made 

significant contributions to Operation 

Tectonic Fury, winner of the 2011 CODiE 

Award for Best Science or Health Instructional Solution, awarded by the Software 

and Information industry Association. A 

selection of the most notable awards and 

recognitions is shown in Table 1. 

Table 1. Awards and professional honors received in FY 2011 by ORNL Sustainable Transportation 

Program researchers

Lawrence F. Allard, Jr.

Nina Balke

Teresa L. Barone 

Gary J. Capps

Gary J. Capps

Madhu S. Chinthavali

Virginia H. Dale, Michael R. 

Hilliard, Esther S. Parish, 

Deanne J. Brice, Charles T. 

Garten, Jr., Alexandre Sorokine, and Robert M. Whitten

Claus Daniel

Best Paper in the materials applications field from 

Microscopy and Microanalysis Journal

DOE Office of Science Early Career Award

DOE Office of Science Outstanding Mentor Award 

DOE Office of Science Outstanding Mentor Award

Appointed to the Federal Motor Carrier Safety Administration’s Smart Roadside Initiative Technical 

Advisory Committee 

Outstanding Presentation, Applied Power Electronics 

Conference and Exhibition

Mission 2 of Operation Tectonic Fury, winner of the 

2011 CODiE Award for Best Science Instructional 

Solution, awarded by the Software and Information 

industry Association; and the 2011 Award of Excellence from Technology & Learning Magazine

U.S. co-chair for the energy storage session, National 

Academy of Engineering German-American Frontiers 

of Engineering Symposium 
Sustainable Transportation Program • OAK RIDGE NATIONAL LABORATORY

Introduction

16

Sujit Das

Sujit Das

Diane Davidson

Diane Davidson

Diane Davidson

Stacy C. Davis

Rebecca A. Efroymson

Rebecca A. Efroymson

Oscar Franzese

Rick Goeltz

David L. Greene

David L. Greene

David L. Greene and 

Zhenhong Lin

Camden R. Hubbard

Ho-Ling Hwang

Keith L. Kline

H. E. (Bill) Knee and 

Oscar Franzese

Appointed to the Transportation Research Board Committee 

on Transportation Economics

Appointed to the Transportation Research Board Committee 

on Alternative Transportation Fuels and Technologies

Board of Directors, Intelligent Transportation Society of Tennessee 

Appointed to the Transportation Research Board Committee 

on Critical Transportation Infrastructure Protection 

Chair, Federal Transit Authority’s Transit Rail Advisory Committee for Safety

Appointed to the Transportation Research Board Committee 

on Alternative Transportation Fuels and Technologies

Peer reviewer for the Environmental Protection Agency 

report, Biofuels and the Environment: First Triennial Report to 

Congress. 

Appointed to the National Research Council Committee on 

Sustainable Development of Algal Biofuels

DOE Office of Science Outstanding Mentor Award

Chair, Transportation Research Board Technical Expert Task 

Group to Design and Implement a System for Archiving and 

Disseminating Data from Strategic Highway Research Program 2 Reliability and Related Studies

Appointed to the Board of Directors of the American Council 

for an Energy Efficient Economy

Edward L. Ullman Award from the Transportation Geography 

Specialty Group of the Association of American Geographers 

2011 Department of Energy Vehicle Technologies Program 

Research and Development Award

Fellow, ASM International

Appointed to the Transportation Research Board Committee 

on Travel Survey Methods 

Invited to participate in the Roundtable for Sustainable Biofuels Expert Group on Indirect Impacts

Transportation Research Board 2011 Pyke Johnson Award 

for the outstanding paper published in the field of transportation systems planning and administration
Sustainable Transportation Program • OAK RIDGE NATIONAL LABORATORY

Introduction

17

Michael J. Lance

Michael J. Lance

Nickolay V. Lavrik, Panos G. 

Datskos, Scott R. Hunter, 

and Barton Smith, ORNL; 

Michael J. Sepaniak and 

James F. Patton, University 

of Tennessee

Jan-Mou Li

Zhenxian Liang

Zhenhong Lin

Philip J. Maziasz

Mitchell Olszewski

James E. Parks and William 

P. Partridge, Jr.

William P. Partridge, Jr.

Duminda I. Randeniya

Kevin J. Rhodes

Kevin J. Rhodes

Excellence in Oral Presentation at the SAE Powertrains, Fuels 

& Lubricants Meeting

Selected to be published in the SAE International Journal of 

Engines, “Characterization of Field-Aged Exhaust Gas Recirculation Cooler Deposits”, 2010-01-2091 

R&D 100 Award, Nano-Optomechanical Hydrogen Safety Sensor Based on Nanostructured Palladium Layers

Appointed to the Transportation Research Board Committee 

ABJ30 on Urban Transportation Data and Information Systems

Guest editor, Journal of Advances in Power Electronics, for a 

special issue on “EMI/EMC, Passive Components and Power 

Electronics Integration Techniques” 

Appointed to the Transportation Research Board Committee 

on Transportation Energy

Battelle Distinguished Inventor 

Appointed to a multinational North Atlantic Treaty Organization working group charged with assessing the rare earth 

materials situation relative to electric motive power systems

Federal Laboratory Consortium Excellence in Technology 

Transfer Award for “Laser-induced Fluorescence Fiber-optic 

Measurement of Fuel in Oil” 

DOE Office of Science Outstanding Mentor Award

Member, Professional Advisory Committee for “Improving 

Log Transportation with Data Based Monitoring and Analysis 

in Northern Wisconsin and Upper Peninsula of Michigan,” a 

study by the Michigan Technological University and University 

of Wisconsin- Superior

Featured researcher in the Pacific Acoustic Corporation Spring 

Newsletter for his acoustic emission work on battery materials

2011 Margaret C. Ettner Student Lecturer Award from the 

American Crystallographic Association
Sustainable Transportation Program • OAK RIDGE NATIONAL LABORATORY

Introduction

18

Kevin J. Rhodes, Melanie 

J. Kirkham, Roberta A. 

Meisner, E. Andrew Payzant, 

Nancy J. Dudney, and Claus 

Daniel

David J. Singh

Scott Sluder

Gui-Jia Su and Lixin Tang

Erin Webb

Andrew A. Wereszczak

60th Annual Conference on Applications of X-ray Analysis 

Best Poster Award for “In situ XRD Characterization of Thin 

Film Electrodes for Electrochemical Energy Storage Devices”

Elected to the Executive Committee of the American Physical 

Society, Division of Computational Physics

Vice Chair, SAE Land & Sea Group 

Best Paper at the 7th IEEE Vehicle Power and Propulsion 

Conference

Member, Biomass Research and Development Initiative Interagency Working Group for Bioenergy Logistics

Fellow, American Ceramic Society
Sustainable Transportation Program • OAK RIDGE NATIONAL LABORATORY

Introduction

19

Publications and Presentations

Sustainable Transportation Program staff 

produced more than 300 journal articles, 

technical reports, presentations, and papers in conference proceedings. A breakdown by sponsor and type of publication 

is presented below. 

Research sponsored by the Biomass Program resulted in 55 publications and 

presentations in FY 2011. Source: ORNL Publication Tracking System.

DOE Biomass Program
Sustainable Transportation Program • OAK RIDGE NATIONAL LABORATORY

Introduction

20

Research sponsored by the Department of Transportation, state agencies, and non-profit organizations performed by staff in ORNL’s Center 

for Transportation Research resulted in 18 publications and presentations in FY 2011. Source: ORNL Publication Tracking System.

Research sponsored by the DOE/EE Fuel Cell Technologies 

Program resulted in 12 publications and presentations in 

FY 2011. Source: ORNL Publication Tracking System.

DOE Fuel Cell Technologies Program

DOT and Other Sponsors
Sustainable Transportation Program • OAK RIDGE NATIONAL LABORATORY

Introduction

21

Research sponsored by the DOE/EE Vehicle Technologies 

Program resulted in 247 presentations and publications in 

FY 2011. Source: ORNL Publication Tracking System.

DOE Vehicle Technologies Program
blank page
R

Billion Ton Update

Bioenergy Knowledge Discovery Framework

&D

Ethanol Blends Materials Compatibility

Biomass Supply Chain Modeling & Analysis

Sustainability of Biomass Production

Biomass
Sustainable Transportation Program • OAK RIDGE NATIONAL LABORATORY

24

Highlights

Billion Ton Update

In 2005, ORNL led the Billion-Ton Study 

for the U.S. Departments of Energy and 

Agriculture. The resulting landmark report, Biomass as Feedstock for a Bioenergy 

and Bioproducts Industry: The Technical 

Feasibility of a Billion-Ton Annual Supply, 

played a pivotal role in the development 

of the Energy Independence and Security 

Act of 2007 with findings confirming the 

technical feasibility of U.S. lands supplying a billion dry tons of biomass annually. 

Now in another groundbreaking study, 

ORNL, leading a team of researchers from 

seven universities, two national laboratories (ORNL and the Idaho National 

Laboratory) and four U.S. Department of 

Agriculture (USDA) offices, has updated 

the original study. The main findings 

remain the same: the ambitious goals the 

United States has set for biofuels use are 

not only achievable but sustainable. The 

2011 report, however, goes beyond merely 

updating the previous report to provide 

a comprehensive resource assessment 

and address many of the issues raised 

One season’s growth of potential cellulosic biomass feedstock.

since 2005. The update is remarkable in 

its detailed temporal and spatial resolution (annual supply curves at the county 

level for almost 20 different feedstocks) 

and attention to environmental sustainability, not only providing information on 

the potential quantities of feedstocks 

and their cost, but also addressing the 

resulting land use changes. The study also 

sets a new standard for transparency and 

data accessibility as all the county-level 

results were made available to the public, 

researchers, and industry through the Bioenergy Knowledge Discovery Framework, a 

web-based application developed at ORNL 

that allows visualization of the data as 

maps and selective downloading of any 

and all of the data generated by the study.

Released in August 2011 by DOE, the 

Billion-Ton Update can be found online 

at eere.energy.gov/biomass/pdfs/billion_ton_update.pdf or on the Bioenergy 

Knowledge Discovery Framework at www.

bioenergykdf.net.
Sustainable Transportation Program • OAK RIDGE NATIONAL LABORATORY

Highlights

25

•	 U.S. Department of Energy. 2011. U.S. Billion-Ton Update: Biomass Supply for a Bioenergy and Bioproducts Industry. R. D. Perlack and B. J. Stokes (study leads). ORNL/TM2011/224. Oak Ridge National Laboratory, Oak Ridge, Tennessee.

•	 Perlack, R. D., et al. 2005. Biomass as Feedstock for a Bioenergy and Bioproducts Industry: 

The Technical Feasibility of a Billion-Ton Annual Supply. DOE/GO-102995-2135 or ORNL/

TM- 2005/66. Oak Ridge National Laboratory, Oak Ridge, Tennessee.

Publications
Sustainable Transportation Program • OAK RIDGE NATIONAL LABORATORY

26

Highlights

The Bioenergy Knowledge 

Discovery Framework 

Meeting the challenging goals the 

United States has set for bioenergy 

use requires new ways of accessing, 

evaluating, synthesizing, and visualizing information. The DOE Office of 

Biomass Program (OBP) tapped ORNL 

in 2008 to develop a framework to 

promote sharing and integration of 

bioenergy resource information; engage 

various stakeholder communities; offer 

guidance and access to comprehensive data, modeling, and visualization 

resources; and incorporate OBP- and 

partner-funded research. The result is 

the Bioenergy Knowledge Discovery 

Framework (KDF), a web-based platform that provides access to the latest 

data, models, and analysis tools. The 

Bioenergy KDF seeks to harmonize 

data from different sources and provide 

integrated decision-making capabilities using Web 2.0 and social networking technologies. Unique among such 

resources, the Bioenergy KDF allows 

users to pose questions to be referred to 

experts for answers. The website (www.

bioenergykdf.net/) was released in January 2011 and has experienced consistent growth, accumulating nearly 700 

registered users as of January 2012, 

with an average of 150 unique site visits 

per day.

The Bioenergy KDF contains approximately 1,400 curated spatial data 

sources, more than 1,200 downloadable data sets, more than 1,100 map 

services at different scales, hundreds 

of curated resources describing models 

and important journal articles, and links 

to many web resources. Data from the 

Billion Ton Update; the Biofuel Infrastructure, Logistics, and Transportation 

(BILT) model; and the National Bioenergy Routing Model were successfully 

integrated in 2011. In conjunction with 
Sustainable Transportation Program • OAK RIDGE NATIONAL LABORATORY

Highlights

27

publication of the Billion Ton Update report in August 2011, the Bioenergy KDF 

provided the main source of access to 

the report, data, and basic analysis capabilities. Feedstock data can be downloaded in either raw form or in a spreadsheet 

format based on user-supplied criteria. 

Data can also be visualized within a 

map interface to allow examination of 

biomass resource distribution based on 

scenario, year, and estimated biomass 

crop prices. The BILT model, released in 

November 2011, allows users to explore 

the biofuel supply chain for a state by 

displaying where biomass resources can 

be drawn from, sent for refining, and 

distributed for end use. The National 

Bioenergy Routing Model is a multimodal 

transportation model that provides an 

easy user interface for analysis of basic 

routing results for transporting biomass and bioenergy products.

In 2012, updates to the Bioenergy 

KDF will provide additional avenues for 

collaboration, new tools and models 

for web-based bioenergy analysis, and 

a subject matter expert database to 

connect researchers and experts from 

across the bioenergy research community.
Sustainable Transportation Program • OAK RIDGE NATIONAL LABORATORY

28

Highlights

Ethanol Blends Materials 

Compatibility Study Released 

ORNL, in collaboration with the National 

Renewable Energy Laboratory and Underwriters Laboratories, has been conducting a study of the compatibility of intermediate ethanol blends and automotive 

fuel dispenser materials. The first report 

on project results was released in 2011 

to assist industry in assessing potential 

material compatibility issues, and to support development of new materials for 

fuel dispenser applications.

The study looked at the metals, elastomers, sealants, cork, and plastics that 

are used in the gasoline fueling infrastructure. Many of these systems have 

been in service for years and were not 

designed for ethanol concentrations 

greater than 10%. “Before E15, E20, 

or intermediate blends of gasoline with 

higher levels of ethanol are introduced 

into the nation’s fueling infrastructure, 

their effects on the fueling infrastructure 

must be determined,” said Mike Kass of 

the ORNL Energy and Transportation Science Division. To do this, Kass explained, 

the team conducts controlled tests under 

accelerated conditions to determine 

potential damage over a lifetime of component use in ethanol-blended gasoline. 

Previous efforts centered on intermediate ethanol levels ranging from 10 to 

25% ethanol, while recent activities have 

focused on blends of 50 and and 85% 

ethanol. 

During the project, ORNL developed a 

unique stir tank facility to expose material samples to various test fuels, allowing many materials to be screened in a 

relatively short time. The test tanks are 

sealed, held at elevated temperature, 

and continuously stirred for 4–16 weeks. 

Some of the samples are immersed in 

the test fluid, while others are tested in 

the vapor space to determine whether the 

fuel vapors are also damaging to the materials. Samples are removed periodically 

and analyzed for corrosion, sealability, 

durability, and leakage.
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29

The results showed metals exhibited 

little to no measureable corrosion 

in intermediate blend fuels. Different classes of elastomer materials 

(fluorocarbons, and so forth) exhibited 

generally consistent behavior, with 

some showing very little change when 

exposed to intermediate ethanol blends 

and others changing substantially. The 

researchers found that newer sealants 

passed the leakage tests; older sealants 

not designed for ethanol did not. Study 

results for plastics and cork are still 

•	 Kass, M. J., T. J. Theiss, C. J. Janke, S. J. Pawel, and S. A. Lewis. 2011. Intermediate 

Ethanol Blends Infrastructure Materials Compatibility Study: Elastomers, Metals, and Sealants. ORNL/TM-2010/326. Oak Ridge National Laboratory, Oak Ridge, Tennessee.

pending and will be reported when 

available. 

This information will play a critical 

role in designing new infrastructure 

systems to handle intermediate 

levels of ethanol-blended gasoline. 

In addition, according to Kass, the 

data will help to advance development of adequate retrofit kits for 

existing infrastructure, which will 

enable higher levels of ethanol to be 

sold.

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30

Highlights

Biomass Supply Chain 

Modeling and Analysis

A key challenge in achieving U.S. energy 

independence goals is synchronizing 

all the steps in the biomass-to-biofuels 

supply chain. Integrated analysis of the 

entire supply chain is needed to identify 

bottlenecks and alleviate them before 

major costs are incurred. ORNL took 

a major step in this direction this year 

with the release of a new version of its 

Integrated Biomass Supply Analysis 

and Logistics Model (IBSAL). Originally 

released in 2008, IBSAL simulates the 

flow of biomass through collection, 

transport, storage, and preprocessing 

and estimates energy consumption and 

costs. The new version, IBSAL-MC (MC 

stands for multi-crop), is a hybrid pushpull model. The farm side of operations 

pushes biomass during a harvest season 

to ensure all available biomass is collected. The conversion side pulls adequate 

feedstock to meet biorefinery needs at 

the other end. The multi-crop feature of 

the model ensures that the push and pull 

requirements are met from every available cellulosic biomass feedstock that 

meets a biorefinery’s specifications. 

Unlike conventional models used to analyze the cost of logistics, IBSAL considers 

conditions such as changes in moisture 

due to rain or snow; crop maturity; and 

potential losses of dry matter during field 

operations or in storage. IBSAL uses 

core functions and specific data to create 

unique logistics modules for different 

crop types and biomass growing regions. 

The model also calculates energy inputs 

IBSAL applied to the supply chain for 

agricultural biomass feedstocks. 
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31

•	 Ebadian, Mahmood, Taraneh Sowlati, Shahab Sokhansanj, Mark Stumborg, and 

Lawrence Townley-Smith. November 2011. “A new simulation model for multi-agricultural biomass logistics system in bioenergy production.” Biosystems Engineering

110(3):280–290.

and carbon emissions to identify ways to 

minimize the environmental impacts of 

bioenergy feedstock supply chains. These 

capabilities make IBSAL a unique tool for 

minimizing risks associated with the flow 

of high-quality, cost-effective feedstock to 

a biorefinery. 

In a recent application, the model was 

used to simulate a proposed cellulosic 

ethanol plant requiring 750 dry metric 

tons of straw per day to produce 70 ML 

of ethanol per year. The model showed 

that despite the abundance of straw in 

the region—more than 5 times the annual 

demand of the plant—the daily demand 

of the plant would be fully met for only 

104 days. Only 92% of the total annual 

demand would be met. Approximately 530 

farms were required within a radius of 64 

miles to meet the daily demand of 750 

tons. Several managerial insights were 

given to improve the biomass logistics 

system in terms of demand fulfillment, 

logistics costs, and resource utilization, including reconfiguring on-farm and at-plant 

storage to increase daily demand fulfillment.

IBSAL can be accessed through the Bioenergy Knowledge Discovery Framework at 

www.bioenergykdf.net. 

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Highlights

Sustainability of Biomass Production

Concerns about the social, economic, 

and environmental impacts of ambitious goals to displace large portions of 

petroleum and other traditional sources 

of energy with biofuels/bioenergy in 

a relatively short time are not unique 

to the United States; similar concerns 

have been raised in other countries that 

have other goals, potential feedstocks, 

and cropping and conversion systems. 

A worldwide need exists for high quality 

data on the impacts and sustainability of biofeedstock production and for 

comprehensive analyses of the production, use, and sustainability of biofuels. 

The ORNL Center for BioEnergy Sustainability (CBES), a leading resource for 

dealing with the environmental impacts 

and ultimate sustainability of biomass 

production for conversion to biofuels and 

bio-based products, provides those data 

and analyses—not just for the burgeoning U.S. bioenergy industry but, through 

global partnerships and outreach, for the 

entire world.

In 2011, CBES research focused on issues related to land-use change and how 

to define and measure characteristics of 

bioenergy sustainability. A cross-disciplinary CBES team identified a suite of 

19 indicators in 6 categories that can be 

used to characterize the environmental 

sustainability of bioenergy systems. The 

suite is intended to be a practical toolset for characterizing key environmental 

effects of a range of bioenergy systems, 

including different pathways, locations, 

and management practices. In other 

research, the landscape implications of 

bioenergy feedstock choices were shown 

to be significant and to depend on siteRelationships among energy, land use, and climate change. 

Arrows indicate influence of one factor on another.

Climate Change > Energy

• Energy Options

• Intensity of use

• Distribution of supply and 

demand for energy

Energy > Climate Change

• Greenhouse gas emissions and 

 carbon sequestration

• Localweather and air quality

Energy > Land Use

• Energy extraction, production, 

 and distribution footprint

• Infrastructure and settlement 

 plans

Climate Change > Land Use

• Productivity 

• Suitability for life forms and 

 management practices

 • Distribution of land uses

 • Human settlement patterns

Land Use > Climate Change

• Release of greenhouse gases

• Amount of carbon sequestration

• Weather changes

• Vulnerability to climate change

Land Use > Energy

• Options for energy extraction, 

 infrastructure, and production

• Efficiency of energy production 

• Demand for energy

Climate Change, 

Land Use, Energy 

Nexus 

• Ecosystem services

• Albedo, Latent heat

• Sensitive ecosystems

• Fire
Sustainable Transportation Program • OAK RIDGE NATIONAL LABORATORY

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33

specific land use practices and their environmental impacts. Although land-use 

changes and carbon emissions associated with bioenergy feedstock production 

are dynamic and complicated, lignocellulosic feedstocks offer opportunities that 

enhance sustainability when compared 

to other transportation fuel alternatives. 

Furthermore, contrary to concerns that 

have been raised about land-use change 

and diversion of corn exports because of 

ethanol production in the United States, 

a decomposition analysis of the empirical data on the sources of corn found 

little support for the argument that either 

of those phenomena played a significant 

role as U.S. ethanol production increased 

over the past decade. This and related 

research highlighted the need for additional scientific analysis to correct key 

assumptions and support more realistic 

modeling of land-use change compared 

to current efforts. Finally, research demonstrated how tightly land use, climate 

change, and energy choices are linked, 

something previous studies have failed to 

address in an integrated fashion. For the 

future, decision makers will need integrated approaches that consider all of these 

elements and their interactions, as well as 

other anthropogenic forces, when making 

policy decisions.

•	 Dale, V.H., R. A. Efroymson, and K. L. Kline. 2011. “The land use – climate change – 

energy nexus.” Landscape Ecology 26(6):755–773.

•	 McBride, A. C., V. H. Dale, L. Baskaran, M. Downing, L. Eaton, R. A. Efroymson, C. 

Garten, K. L. Kline, H. Jager, P. Mulholland, E. Parish, P. Schweizer, and J. Storey. 2011. 

“Indicators to support environmental sustainability of bioenergy systems.” Ecological 

Indicators 11(5):1277–1289.

•	 Oladosu, G. A., K. Kline, R. Martinez and L. Eaton. 2011. “Sources of Corn for Ethanol 

Production in the United States: A Review and Decomposition Analysis of the Empirical Data.” Biofuels, Bioprod. Bioref. 5:640–653. 

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Wireless Roadside Inspection

Fuel Tax Evasion Detection System

&D

Intelligent Transportation Systems 

Deployment Survey

New Method for Estimating Fuel Economy

by Vehicle Class

Department of 

Transportation
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Highlights

Smart Roadside Initiative for 

Commercial Vehicle Operations—

Wireless Roadside Inspection

In early 2011 ORNL successfully completed phase 2 of the Wireless Roadside 

Inspection (WRI) Program, the WRI Pilot 

Test. WRI is part of the Federal Motor Carrier Safety Administration (FMCSA) Smart 

Roadside Initiative, whose goal is to leverage technology to create an environment 

in which information can be shared among 

the various parts of the transportation system (commercial vehicles, motor carriers, 

enforcement resources, highway facilities, 

and so forth) to improve motor carrier 

safety, security, operational efficiency, and 

freight mobility. 

Each year both the number of commercial 

vehicles on the road and the number of 

miles they travel increase, but inspection 

resources tend to remain constant and in 

some cases have actually decreased. WRI 

holds the promise of increased inspections—including on the fly—and thus 

greater safety for everyone on our nation’s 

roadways.

The goal of the pilot test was to determine the viability and effectiveness of 

wireless commercial motor vehicle inspections using current telematics techniques and systems. Additionally, the 

pilot was used to further refine the WRI 

concept of operations and the WRI systems architecture. An important part of 

the pilot was establishing gratis partnerships with commercial carriers, commercial motor vehicle and safety sensor 

technology manufacturers, and telematics 

service providers. 

During the pilot test, safety data messagWireless roadside inspection system overview.
Sustainable Transportation Program • OAK RIDGE NATIONAL LABORATORY

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37

es, which included vehicle identification 

information, driver identification information, and driver status information, were 

successfully transmitted to a government 

back office system using commercial 

mobile radio services, demonstrating 

end-to-end system functionality. During 

the pilot, 1,200 safety data messages 

were successfully transmitted in real 

time, many of them from vehicles traveling at highway speeds. As a follow-on 

to this effort, FMCSA has tasked ORNL 

with conducting a Field Operational Test 

that will include a complete end-to-end 

system with multiple fleets, multiple 

vehicles, and multiple technology partners, leveraging what was accomplished 

in the pilot test and similar projects at 

ORNL to streamline the complexity of the 

effort and explore and abate risk areas. 

The Field Operational Test total system 

scope (consisting of partners, hardware, 

software, and vehicles) is small enough 

to be manageable but large enough 

(1,000 vehicles) to yield statistically 

meaningful test data that will answer the 

go/no-go question for the deployment of 

the WRI system nationally. 

•	 Franzese, O., et al. 2011. Wireless Roadside Inspection Phase II Tennessee WRI CMRS Pilot 

Test Final Report. ORNL/TM-2012/40, Oak Ridge National Laboratory, Oak Ridge, Tennessee.

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Highlights

Development of a Supply Chain–

Based Fuel Tax Evasion 

Detection System

A multidisciplinary team at ORNL has 

successfully completed proof of concept 

testing of a novel system to detect fuel 

tax evasion.

Fuel taxes provide the major source of 

funding for the U.S. highway system. 

While ensuring that motor fuel and other 

highway use taxes are properly collected 

is a priority for the Federal Highway Administration (FHWA), the complexity of 

the fuel supply chain in the United States 

creates numerous opportunities to evade 

fuel taxes—amounting to $3 billion in lost 

revenues by one estimate1. Hence, FHWA 

sponsored an Exploratory Advanced 

Research Project at ORNL to provide a 

comprehensive system aimed at reducing 

or eliminating fuel tax evasion schemes 

involving fuel tanker trucks. 

The approach taken by ORNL included a 

number of innovations such as integration of multiple measures tailored for 

specific diversion schemes, development 

and evaluation of chemical marking 

agents and in-line sensors to detect the 

presence and concentration of marked 

fuels, and integration of advances in sensor technology, data acquisition, wireless 

communications, vehicle tracking, and 

information analysis. In addition, because 

most existing approaches are reactive, 

one of the goals of the ORNL approach 

was to provide a system that would 

proactively monitor and determine the 

legitimacy of individual loads, offloads, 

and movements of petroleum products in 

near real time.

Spectral response of marked diesel at two different excitation wavelengths, 405 nm 

and 635 nm. The 405 nm peak is a natural by-product of diesel (marked or unmarked), 

while the 635 nm peak is a by-product of the custom marker. Measuring and dividing 

the intensity of the two peaks provides a self-referenced measurement of the marker 

concentration strength.

1 Garvey, Jane F. Statement to the U.S. House, Committee on Public Works and Transportation. Shortfall 

in Highway Trust Fund Collection. Hearing, August 10, 1994. Available at: testimony.ost.dot.gov/test/

pasttest/94test/garvey3.pdf.
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Visible fluorescence during the excitation of the fuel marker.

The prototype system includes 

•	 a stable, ORNL-developed fuel marker, 

compatible with legacy fuels and 

engines, that can be detected in the 

parts-per-billion range;

•	 a suite of prototype fuel transport 

vehicle sensors to monitor, among 

other things, whether any of the access 

points to the trailer are opened;

•	 a communications system designed to 

collect sensor signals from the trailer 

(for example, fuel level, weight), convey 

the sensor signals wirelessly from the 

trailer to the tractor, receive sensor 

data from the trailer, condition and format the sensor signals for acceptance 

by the onboard computer, and be 

capable of sending data packets to a 

back office system for processing; 

•	 an ORNL-developed intelligent geographical information system to 

facilitate near real time notification of 

suspicious variation in standard delivery processes, tracking the tanker 

as it travels to its destinations on the 

delivery route; and

•	 a control center designed to communicate with law enforcement personnel in a timely manner, enabling interdiction and investigation of potential 

fuel diversion activities on a real time 

basis. 

•	 Capps, G., et al. 2011. Supply Chain–Based Solution to Prevent Fuel Tax Evasion: 

Proof of Concept Final Report. ORNL/TM-2011/132, Oak Ridge National Laboratory, 

Oak Ridge, Tennessee. 

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Highlights

National Intelligent Transportation 

Systems Deployment Survey

For nearly 20 years, the U.S. Department of Transportation (DOT) has had an 

ambitious program to create a national 

infrastructure of intelligent transportation 

systems (ITS) technologies consisting of 

sensors to gather data on traffic conditions, media to disseminate traffic advisories to travelers, and systems to manage 

transit, incident management, and public 

safety. ORNL has been on board since 

the beginning, supporting management 

of the national ITS program by gathering, 

collating, and analyzing data; and helping 

disseminate the information. Starting in 

1996, the DOT ITS Joint Program Office 

tasked ORNL to gather data on the status 

of ITS deployment in major cities and to 

analyze the data to track progress toward 

national goals. 

Data are gathered through a series of 

surveys covering a variety of information on the extent and character of ITS 

deployment. The surveys cover nearly 

2000 state and local agencies in 108 of 

the nation’s largest cities. The data collected are used by DOT to manage the 

ITS program, to respond to Congressional 

inquiries, and to allocate federal grants 

to support ITS deployment. The Deployment Tracking Website (www.itsdeployment.its.dot.gov), created and maintained 

by ORNL, provides access to survey 

results as well as a national summary 

report of the latest results. The website is 

the only publicly available source for this 

type of information, serving as a resource 

for researchers, private vendors, other 

agencies, the general public, and decision 

makers. 

The data from the most recent survey in 

2010 reveal that the ITS program has 

moved from being experimental to mainstream, and interest in continuing investments in ITS technologies is very strong. 

When asked about near term deployment 

plans, most of the different agency types 

reported they will expand current deployments, and about half are planning to 

invest in new technologies. Other trends 

highlighted in the 2010 national summary report include:

Deployment of ITS: A Summary of the 

2010 National Survey Results

www.its.dot.gov/index.htm

Final Report — August 2011

FHWA-JPO-11-132
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41

•	 Gordon, Steve, and Jeff Trombly. 2011. Deployment of ITS: A Summary of the 2010 

National Survey Results. FHWA-JPO-11-132, ITS Joint Program Office, Research and Innovative Technology Administration, U.S. Department of Transportation, Washington, 

D. C. 

•	 the almost total automation of toll collection, which has improved safety, mobility, and accuracy while reducing costs;

•	 the growth of real-time data collection 

through traffic sensors and cameras, 

allowing agencies to provide real-time 

traffic advisories and take a more active 

role in traffic management;

•	 technical advances that support proactive control of traffic through mechanisms like managed lanes, ramp metering, and adaptive traffic signals;

•	 migration of traveler information from 

infrastructure systems such as radio and 

dynamic message signs to personalized 

messaging through mobile devices and 

social media.

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Highlights

New Method for Estimating Fuel 

Economy by Vehicle Class

ORNL was tasked by the Federal Highway 

Administration (FHWA) Office of Highway 

Policy Information to develop a new method to generate annual, national estimates 

of average fuel economy (in terms of 

mpg) and number of vehicles registered 

by vehicle class for the annual publication 

Highway Statistics. The data published in 

Highway Statistics is used by all levels of 

government to assess the performance of 

the U.S. highway transportation system, 

and to identify future highway system 

options. The data are extensively used by 

federal, state, and local agencies; academia; industry; consultants; professional 

organizations; and the public for a host of 

purposes.

The goal of the new methodology is to 

ensure that the statistics on total vehicle 

miles traveled, number of vehicles, and 

total fuel consumption are consistent and 

reasonable. It takes a two-step approach. 

First, fleet fuel economy by vehicle class 

is estimated based on vehicle stock models1

. Then a reconciliation model is used 

to adjust the initial estimates from the 

vehicle stock models and match vehicle 

miles traveled information and total fuel 

consumption. This reconciliation model 

uses a systematic approach that produces documentable and reproducible 

results. The basic framework is based on 

a mathematical programming formula 

to minimize the deviations between the 

For 1998–2003, passenger vehicle fuel economy results from the reconciliation 

model are similar to those published in Table VM-1 of Highway Statistics. Since 

2004, passenger vehicle fuel economy results from the reconciliation model show 

less variation than those published in Table VM-1.

1 Vehicle stock models, also known as vehicle fleet models, are econometric models used by transportation 

analysts and traffic engineers to estimate and forecast policy impacts related to overall fleet performance.
Sustainable Transportation Program • OAK RIDGE NATIONAL LABORATORY

Highlights

43

fuel economy estimates published in the 

previous year’s Highway Statistics and 

the results from the vehicle stock models, subject to the constraint that fuel 

consumption for different vehicle classes 

must sum to the total fuel consumption 

estimate in the current year’s Highway 

Statistics.

For ease of use, the new method was 

implemented in a Microsoft Office 2007 

Excel-based computer program with a 

simple user interface designed using macros. A “solver” was built into the program 

to allow “one click” model runs.

The results generated by this new methodology compare favorably with previous 

numbers generated manually and with 

industry trends; however, the method 

provides a smoother time series for the 

fuel economies by vehicle class. It also 

has the advantage that it uses the most 

up-to-date and best available data with 

sound econometric models. Further, the 

formula used in the reconciliation model 

will enable a relatively smooth transition from FHWA’s current procedure to 

the new method, avoiding a “kink” in 

the statistics in the year the transition is 

made. 

•	 Chin, S.-M., K. Dabbs and H.-L. Hwang. 2011. “New Methodology for Estimating Fuel 

Economy by Vehicle Class.” Presented at the Transportation Research Board 90th Annual Meeting, Washington, D.C., January 23–27.

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Reducing the Production Cost of High

Strength Carbon Fibers for Storage

&D

Investigating Aging and Associated

Degradation of Membrane Electrode

Assemblies

Vessel Design and Fabrication Technology

for Stationary Hydrogen Storage

Hydrogen 

and Fuel Cell 

Technologies
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Highlights

Reducing the Production Cost of 

High Strength Carbon Fibers for 

Hydrogen Storage

ORNL is investigating new precursor materials and production processes to yield 

lower cost high-strength fibers. Because 

of its remarkable strength-to-weight ratio 

and damage tolerance, high strength 

carbon fiber is the material of choice for 

durable, lightweight storage vessels for 

high pressure gas in both vehicular and 

stationary storage applications. However, 

these storage vessels are expensive, and 

carbon fiber is the reason. Between 40% 

and 70% of the storage vessel cost is for 

the carbon fiber (the precursor material 

accounts for about 40-60%). The conventional precursor for high strength carbon 

fibers is solution spun polyacrylonitrile 

(PAN). Melt spun PAN, if successful, will 

be much cheaper because it has fewer 

process steps and there is no cost for 

solvent or solvent operations; however, it 

is technically far more challenging. 

Until specific cost and property targets 

for compressed hydrogen storage are established, the goal is a 24K tow with700 

Ksi ultimate tensile strength, and 33 Msi 

tensile modulus fiber with a 25% reduction in cost. To date, the ORNL team has 

successfully prepared and characterized 

acrylonitrile copolymers, including those 

with methyl acrylate, in controlled molecular weights. The team has also demonstrated the generation of melt spun PAN 

using only modified water as a plasticizer 

ORNL’s highly versatile, modular precursor and fiber evaluation system capable of processing fibers in tow counts from 20 to more than 50,000 filaments.
Sustainable Transportation Program • OAK RIDGE NATIONAL LABORATORY

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47

(no solvents) and produced melt spun 

PAN precursor fibers with the desired 

denier (10 to 20 μm in diameter) using a 

one-step spinning/drawing process.

Converting precursor fibers into carbon fibers is normally accomplished 

by time- and energy-intensive thermal 

treatment. The project team is investigating revolutionary new processing 

methods that could potentially deliver 

higher line speeds with lower energy use 

and costs. The team is also establishing 

a modular carbon fiber research pilot 

line to evaluate these processes against 

conventional industrial processes using 

a conventional pilot line for benchmarking advanced technologies. In the near 

future, an advanced technology pilot line 

will be assembled to demonstrate that 

the advanced process modules work 

together as a functional system and to 

perform system optimization. Advanced 

carbon fiber conversion processes would 

not only increase production but also 

significantly reduce the required capital 

investment and energy demand per unit 

of output, potentially reducing cost by 

half, and expanding U.S. competitiveness into the manufacturing of higher 

strength carbon fibers.

•	 Paulauskas, F. L. 2011. “Melt Processable PAN Precursor for High Strength, Low-Cost 

Carbon Fibers.” Presented at the Hydrogen and Fuel Cells Program 2011 Annual 

Merit Review and Peer Evaluation, Arlington, Virginia, May 9–13. Available at www.

hydrogen.energy.gov/pdfs/review11/st093_paulauskas_2011_o.pdf.

•	 Paulauskas, F. L. 2011. “Development of Low- Cost, High Strength Commercial Textile 

Precursor (PAN-MA).” Presented at the Hydrogen and Fuel Cells Program 2011 Annual Merit Review and Peer Evaluation, Arlington, Virginia, May 9–13. Available at 

www.hydrogen.energy.gov/pdfs/review11/st099_warren_2011_p.pdf.

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Highlights

Investigating Aging and Associated 

Degradation of Membrane Electrode 

Assemblies for Proton Exchange 

Membrane Fuel Cells

To reach DOE’s technical targets for 

membrane electrode assemblies (MEAs), 

ORNL is leading a multiorganization effort 

to characterize the microstructures of 

MEA materials. ORNL’s approach involves 

using advanced microscopy techniques 

and establishing collaborations with leading researchers in the field. Researchers 

are able to apply knowledge gained on 

this project to optimize the design and 

manufacture of fuel cell materials and 

assemblies.

Proton exchange membrane fuel cells 

(PEMFCs) are of interest as efficient, 

zero-emission power sources for vehicles. 

The performance of PEMFCs degrades 

during use, and this degradation can be 

directly correlated with the durability of 

the individual material components that 

make up the PEMFC MEAs. However, 

many of the microstructural and compositional attributes that contribute to 

decreased stability of the MEA during 

long-term use are not fully understood 

Z-contrast scanning transmission electron microscopy image 

showing graphene sheet (single- and multi-layered) with individual Pt atoms (brightly imaging) deposited on surface. Note that 

all the Pt atoms deposit preferentially at the edge sites (or steps 

where graphene layers overlap) and not on sites associated with 

the sp2-bonded flat (002) surfaces.
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and must be directly correlated with performance as a function of aging protocols 

in order to identify mitigating strategies 

and improve fuel cell lifetimes.

ORNL is using advanced microstructural 

and microchemical analysis techniques 

to characterize as-processed and electrochemically aged MEAs. These techniques, 

which include high-resolution scanning, 

transmission, and analytical electron 

microscopy, are being used to evaluate structural changes and degradation 

phenomena under load. Large areas of extremely thin (less than 50 nm), fully intact 

MEAs, prepared for transmission electron 

microscopy, have allowed team scientists 

to quantitatively characterize the atomicscale structural and chemical changes 

within the proton exchange membrane 

and electrodes. Furthermore, individual 

constituents and their assemblages within 

the electrodes (carbon-based support, 

ionomer, electrocatalyst particles, and interfaces between the electrode and membrane) are continually being evaluated, 

pre- and post-aging. This microstructural 

evaluation of MEAs is enabling significant stability and performance improvements, and is invaluable for identifying 

the mechanisms contributing to MEA 

degradation and/or failure.

To more fully elucidate the role of catalyst-support interactions on long-term 

stability during aging, a collaboration has 

recently been established with Nissan 

Technical Center to evaluate platinum 

(Pt) catalysts (in terms of dispersion, 

size, and morphology) deposited on a 

series of carbon supports exhibiting 

varying degrees of graphitization. In addition, ORNL has initiated a fundamental 

study of Pt deposition on model carbon 

substrates (single-layer graphene) to understand Pt nucleation and growth mechanisms on extended graphitic surfaces. 

These studies are focused on identifying 

critical bonding, chemical, and structural 

factors that contribute to catalyst degradation/stability during aging.

•	 Wang, C., et al. 2011. “Correlation Between Surface Chemistry and Electrocatalytic 

Properties of Monodisperse PtxNi1-x Nanoparticles.” Advanced Functional Materials 

21(1):147–152.

•	 Wu, G., K. L. More, and P. Zelenay. 2011. “High-Performance Electrocatalysts for Oxygen Reduction Derived from Polyaniline, Iron, and Cobalt.” Science 332:443–447.

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Highlights

Vessel Design and Fabrication 

Technology for Stationary HighPressure Hydrogen Storage

ORNL has successfully completed the 

first year of a multiyear project to develop 

a stationary hydrogen storage system, 

and is on target to meet the DOE cost 

goal for off-board bulk storage. Stationary 

hydrogen storage is a critical element in 

the overall hydrogen production and delivery infrastructure. In this project, ORNL 

leads a multidisciplinary team consisting 

of government, industry, and academia 

to develop and demonstrate design and 

fabrication technologies for an integrated 

steel and concrete high-pressure hydrogen storage vessel that is cost effective 

and scalable. The integrated approach 

will enable

•	 a systematic, integrated design to 

mitigate hydrogen embrittlement associated with the use of high-strength 

steel for high-pressure hydrogen storage,

•	 cost-effective structural materials,

•	 high-productivity, low-cost fabrication 

technologies, and 

•	 embedded sensors to ensure the safe 

and reliable operation of the storage 

system.

Schematic drawing of ORNL’s 

innovative composite vessel for 

safe and cost-effective storage 

of high-pressure hydrogen.
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The size and volume of stationary hydrogen storage vessels are expected to vary 

considerably depending on intended use, 

location, and other economic and logistic 

considerations. For instance, a storage 

vessel at a renewable energy generation 

site may have a lower pressure but much 

larger volume compared to one at a refueling station. Therefore, it is important that 

vessel design is scalable for different sizes 

and pressures. 

This project demonstrated that the preliminary engineering design of an innerlayered steel vessel can sustain 5,000 psi 

pressure based on the relevant American 

Society of Mechanical Engineers Boiler 

and Pressure Vessel code. The preliminary designs for an outer prestressed 

concrete vessel and the steel-concrete 

interface were also completed. Detailed 

design and engineering analyses (including system cost), mockup vessel construction, and testing and demonstration 

are ongoing or planned. In addition to 

meeting the technical challenges, all aspects of the project will be optimized to 

meet or exceed the DOE capital cost goal 

of $300/kg hydrogen by the year 2015 

(note: this goal is under revision at the 

time of publication). 

•	 Feng, Z., J. Wang, and W. Zhang. 2011. “Vessel Design and Fabrication Technology for 

Stationary High-Pressure Hydrogen Storage.” Presented at the Hydrogen and Fuel 

Cells Program 2011 Annual Merit Review and Peer Evaluation, Arlington, Virginia, May 

9–13. Available at www.hydrogen.energy.gov/pdfs/review11/pd088_zhang_2011_o.pdf

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Policy Analysis

Combustion Engines

&D

Energy Storage

Fuels

High Temperature Materials Laboratory

Lightweight Materials

Propulsion System Materials

Power Electronics & Electric Machines

Vehicle & Systems Simulation & Integration

Vehicle 

Technologies
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Highlights

Understanding the diverse purchasing 

behaviors among individuals is crucial for 

designing effective policies to promote 

advanced vehicle technologies. To address 

this need, ORNL developed a market simulation model called Market Acceptance of 

Advanced Automotive Technologies (MA3T). 

Implemented using Microsoft Excel for 

Windows, MA3T simulates market demand 

for advanced vehicle technologies by representing attributes 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 vehicles 

Policy Analysis

Modeling the Market Acceptance 

of Advanced Automotive 

Technologies 

MA3T model framework.

are likely to be operated. Because of this, 

the approach taken in developing MA3T 

was to create a framework for integrating 

data and behavioral models at an appropriate level of detail, whether or not 

the data are fully available or the behaviors fully understood. As more is learned 

about advanced vehicle technologies and 

consumer preferences toward them, the 

model will be updated and improved.

Characteristics distinguishing MA3T 

from other vehicle market models are 

technology richness, detailed consumer 

segmentation, market dynamics, daily 

distance distribution, and range-infrastructure characterization. MA3T includes 
Sustainable Transportation Program • OAK RIDGE NATIONAL LABORATORY

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55

40 choices consisting of 20 powertrain 

technologies for each of 2 vehicle size 

classes: passenger cars and light duty 

trucks. MA3T considers U.S. household 

users of these vehicles as the consumer 

market, which is disaggregated into 1,458 

segments based on 6 dimensions: census 

divisions, residential areas, attitudes toward novel technologies, driving patterns, 

home recharging situations, and work 

recharging situations. MA3T projections 

cover the period from 2005 to 2050 and 

capture the temporal interaction between 

market penetrations and product diversity 

and risk. MA3T characterizes daily driving distance variation with the Gamma 

distribution, validated with real-world 

high-resolution travel data. MA3T explicitly quantifies range anxiety for electric 

vehicles and reflects the effect of charging and refueling infrastructure on the 

appeal of plug-in electric vehicles and 

alternative fuel vehicles.

The core of the model is a nested 

multinomial logit method that predicts 

purchase probabilities among the 40 

choices by each of the consumer segments based on value components 

associated with vehicle attributes, user 

behavior, infrastructure, energy prices, 

and policies. The purchase probabilities 

are translated into market penetrations, 

sales, populations, petroleum use, and 

greenhouse gas emissions. Some of the 

outputs serve as feedback signals and, 

together with exogenous inputs from 

various sources, affect the purchase 

probabilities. 

•	 Lin, Zhenhong, Jing Dong, Changzheng Liu, and David Greene. 2011. “PHEV Energy 

Use Estimation: Validating the Gamma Distribution for Representing the Random 

Daily Driving Distance.” Transportation Research Record: Journal of the Transportation 

Research Board (forthcoming). 

•	 Lin, Zhenhong, and David L. Greene. 2011. “Assessing Energy Impact of Plug-In Hybrid Electric Vehicles: Significance of Daily Distance Variation over Time and among 

Drivers.” Transportation Research Record: Journal of the Transportation Research Board

2252:99–106. 

•	 Lin, Zhenhong, and David Greene. 2010. “Who Will More Likely Buy PHEV: A Detailed 

Market Segmentation Analysis.” Presented at the 25th World Battery, Hybrid and Fuel 

Cell Electric Vehicle Symposium & Exhibition, Shenzhen, China, November 5–9.

Publications
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Highlights

Combustion Engines

Spark Assisted Stoichiometric HCCI 

with E85, a Potential Path to Higher 

Efficiency Engines

ORNL researchers have developed an 

engine combustion strategy that demonstrates a 17% increase in engine 

indicated thermal efficiency, relative to 

conventional spark ignited (SI) combustion with gasoline, by using E85 (a 

blend of 85% ethanol, 15% gasoline) 

under advanced mixed-mode combustion conditions. Efficiency improvements were achieved over a wide range 

in load, making them applicable over a 

large portion of the engine map.

The advanced combustion strategy uses 

mixed-mode combustion to take advantage of the desirable characteristics of 

Net indicated thermal efficiency at 2,000 rpm as a function of net 

IMEP for conventional SI combustion with gasoline and SA-HCCI 

combustion with gasoline and E85.

conventional SI combustion and homogeneous charge compression ignition (HCCI). 

Combustion of a dilute fuel-air mixture is 

initiated with a spark, consuming up to 

40% of the fuel, and the remaining fuel is 

consumed rapidly in a manner similar to 

HCCI. As a result, the combustion strategy 

has been named spark assisted HCCI (SAHCCI).

HCCI achieves greater fuel efficiency than 

conventional SI combustion because of 

unthrottled operation and rapid combustion; however, the process is difficult to 

control. The spark assist provides enhanced 
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control of combustion and an expanded 

operational load range. HCCI studies typically report a maximum load of about 4.0 

bar net indicated mean effective pressure 

(IMEP), whereas SA-HCCI can be operated 

at up to 7.0 bar net IMEP with E85. As a 

result, the efficiency benefits of SA-HCCI 

can be realized over a larger portion of 

the engine map. Greater control over the 

HCCI combustion process enables stoichiometric operation and thus greater 

compatibility with emissions control 

devices. 

This advanced combustion strategy was 

tested with E85, gasoline, and a blend 

of iso-butanol and gasoline. It was found 

that E85 produces higher indicated thermal efficiency and higher maximum net 

IMEP. Thus, this ORNL-developed SA-HCCI 

process holds the promise not only of improved performance, but also of greater 

use of alternative fuels.

•	 Weall, Adam J., and James P Szybist. 2011. “The Effects of Fuel Characteristics on 

Stoichiometric Spark-assisted HCCI.” Technical Paper ICEF2011.60122. ASME Conf. 

Proc. 2011, pp. 243–259.

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Highlights

Dual-Fuel RCCI Combustion Enables 

Efficiency Improvements with Lower 

NOx Emissions

ORNL researchers are teaming with universities and major automotive parts manufacturers to evaluate real-world challenges and 

opportunities of reactivity controlled compression ignition (RCCI). RCCI combustion, 

a variant of homogeneous charge compression ignition, makes use of in-cylinder 

blending of two fuels with different reactivities for improved control of the combustion 

process. The less reactive fuel (for example, 

gasoline or ethanol with diesel) slows the 

reaction and lessens the chance for autoignition. While this approach has been shown 

in simulations and single-cylinder engine experiments to have the potential for high efficiencies and very low nitrogen oxide (NOx) 

and particulate matter (PM) emissions, 

this project is among the first to study the 

potential of this approach under near-realworld conditions. 

The project employed a light duty 

multi-cylinder engine in experiments 

designed to bridge simulation and single-cylinder research engine progress 

to production-viable hardware. Results 

show that RCCI can reduce NOx and PM 

emissions while achieving diesel-like 

or higher brake thermal efficiency—as 

much as 5% higher at higher loads. 

This potential was demonstrated across 

a wide range of steady-state operating 

points consistent with the light duty 

federal drive cycle.

The experiments explored fuel injection 

strategy, dilution levels, piston geometry including compression ratio, fuel 

properties, and emissions. NOx emissions were up to 90% lower than in 

conventional diesel combustion; howevRCCI (blue) using gasoline and diesel compared with conventional 

diesel (red), showing up to 5% increase in brake thermal efficiency 

as engine load is increased at 3,000 rpm. The load expansion of 

RCCI with E20 (20% ethanol, 80% gasoline) is shown in green.
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er, carbon monoxide and hydrocarbon emissions were much higher than in conventional 

diesel combustion and were more similar 

to levels seen in gasoline engines. The 

combination of high carbon monoxide and 

hydrocarbon emissions with low exhaust gas 

temperatures will be a significant challenge 

due to the limited effectiveness of current 

oxidation catalysts at low temperatures.

Other challenges for the multi-cylinder 

engine implementation included matching 

turbomachinery with high exhaust gas recirculation (EGR) and providing sufficient EGR 

cooling with production viable hardware. 

EGR, which can be challenging to implement, is important for additional control of 

in-cylinder pressure rise rates, combustion 

noise, and reactivity stratification at higher 

engine loads.

Various fuel blends were investigated, 

including ethanol-gasoline blends. The 

high octane and charge cooling effects of ethanol were found to have the 

benefit of expanding RCCI operation 

with reduced or no EGR. This effectively 

allows for operation at higher loads with 

better matching of turbomachinery and 

reduced heat rejection requirements, 

which are more consistent with production viable hardware. 

The data are being used in combination with a vehicle model to estimate 

the drive-cycle fuel economy/emissions 

potential of RCCI operation.

•	 Curran, S., R. Hanson, and R. Wagner. Effect of E85 on RCCI Performance and Emissions 

on a Multi-Cylinder Light-Duty Diesel Engine. SAE Paper 2012-01-0376 (forthcoming).

•	 Wagner, R., et al. 2011. “Addressing the Challenges of RCCI Operation on a Light-Duty 

Multi-Cylinder Engine.” Presented at the 2011 Directions in Engine-Efficiency and 

Emissions Research (DEER) Conference, Detroit, Michigan, October 3–6.

Publications
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Highlights

New Understanding of EGR Cooler 

Fouling Mechanisms Provides 

Information for Improving Designs

Scientists at ORNL and the University of 

Michigan are teaming with engineers from 

some of the leading diesel engine manufacturers to gain greater understanding of 

the processes involved in fouling of exhaust 

gas recirculation (EGR) coolers. EGR is a 

key aspect of many advanced combustion 

technologies and has become a mainstay 

for controlling emissions of nitrogen oxides 

(NOx) from diesel engines. Typically this 

is at the expense of engine efficiency/fuel 

economy and increased levels of hydrocarbon (HC) and carbon monoxide emissions. 

This in turn can lead to fouling or failure of 

the EGR system. 

Fouling of the EGR cooler by HCs and 

particulate matter (PM) from the exhaust 

gas stream can reduce the performance 

of the cooler in a matter of hours, causing 

the temperature of the EGR stream to rise, 

potentially producing higher NOx emissions 

and changing the dynamics of the combustion process. Research has shown that 

under moderate engine loads and speeds 

the fouling process tends toward development of a frangible porous layer that is 

highly insulative. However, extended operation at low loads and speeds can result 

in a deposit layer that is less insulative 

because the void volume is substantially 

filled with condensed HCs. The increased 

thermal conductivity of the layer enables 

continued fouling at relatively high rates. 

High HC concentrations relative to the 

PM concentration in the gas stream, as 

is typical of advanced combustion processes, can increase the likelihood of this 

situation. Experience has shown that incidences of plugging in the field are most 

often associated with deposit layers high 

in HCs, which result in a less frangible 

deposit that can become cohesive enough 

to inhibit the EGR flow through the cooler.

Fouled EGR cooler after 200 h fouling test.
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A key aspect of high rates of deposition of 

HCs relative to PM is the gas flow velocity 

through the cooler during low-temperature 

conditions. If the velocity is low compared 

to the maximum design velocity, deposition tends towards HC-dominated layers. 

Thus, applications that operate frequently 

at cold start, low-load, or idle conditions 

are much more likely to experience EGR 

cooler plugging, particularly if the EGR 

cooler design process focuses primarily 

on high-temperature conditions. Project 

team members are currently exploring 

design solutions to reduce the risk of 

plugging in these circumstances, including the use of an oxidation catalyst 

upstream of the cooler or multiple EGR 

coolers with one cooler sized and used 

for low-load conditions, and another 

sized for moderate- and high-demand 

conditions.

•	 Sluder, C. Scott, John M. E. Storey, and Michael J. Lance. 2011. “Hydrocarbon and Deposit Morphology Effects on EGR Cooler Deposit Stability and Removal.” Presented at 

the 2011 Directions in Engine Efficiency and Emissions Research (DEER) Conference, 

Detroit, Michigan, October 3–6.

•	 Storey, John M. E., et al. 2011 “Exhaust Gas Recirculation Cooler Fouling in Diesel Applications: Fundamental Studies, Deposit Properties, and Microstructure.” Proceedings 

of International Conference on Heat Exchanger Jouling and Cleaning - 2011, edited by M.R. 

Malayeri, H. Müller-Steinhagen and A.P. Watkinson, 65-73.

HC deposition rate versus temperature for 0.05 kg/

min/tube EGR stream containing 100 ppm HCs.

Publications
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Highlights

Energy Storage

Improving Lithium-Sulfur Battery 

Technology for Electric Vehicles

Significant market barriers for both plugin hybrid electric vehicles (PHEVs) and 

electric vehicles (EVs) are technology cost 

and vehicle range. ORNL is conducting 

research and development on new battery 

technologies to address those barriers, 

enabling meaningful reductions in U.S. 

petroleum consumption. 

Lithium-sulfur (Li-S) battery technology 

has significantly lower raw material costs 

and offers a much higher energy density 

(that is, provides longer vehicle range) 

than lithium ion batteries. The challenges 

for Li-S batteries are short cycle-life and 

poor efficiency. 

Three key phenomena cause the short 

cycle-life of the Li-S batteries: the irreversible deposition of lithium sulfide (Li2S) on 

the lithium anode through the intrinsic 

polysulfide shuttle, and Li2S and sulfur 

on the cathode; and the formation of 

lithium dendrites. Earlier research revealed that these three obstacles could 

be overcome by using nanostructured 

sulfur-carbon composite cathodes with 

electrolyte additives. ORNL scientists 

devised a cell that achieved a cycle-life 

of 1,000 cycles with no indication of 

capacity decay. In spite of this dramatic 

improvement, the lithium bromide (LiBr) 

additive discovered at ORNL had significant drawbacks: the electrochemical 

intermediates of LiBr are highly corrosive 

and cause severe problems with the current collectors and other metal parts in 

the battery. 

Cycle performance of Li-S batteries with and without 

electrolyte additives.
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The incompatibility of LiBr with battery 

components is driving the search for 

alternative additives that do not corrode. 

There is an additional challenge in that 

the coulombic efficiency and the roundtrip energy efficiency are very low for Li-S 

batteries unless the polysulfide shuttle is 

suppressed or eliminated and the electrochemical reversibility of Li2S formation is 

improved. The ORNL team is investigating 

new materials that could improve both the 

energy efficiency and the cycle life of Li-S 

batteries by optimizing the structure of 

the sulfur-carbon composite to suppress 

the polysulfide shuttle, thereby improving 

the coulombic efficiency; exploring electrolyte additives that can reverse the formation of Li2S; and protecting the lithium 

metal anode by solid electrolyte coating. 

•	 Zengcai, L., W. Fu, and C. Liang. 2011. “Lithium Sulfur Batteries.” In Handbook of Battery 

Materials, Second Edition, edited by Claus Daniel and Jürgen O. Besenhard, 811–840. 

Weinheim, Germany: Wiley-VCH Verlag GmbH & Co. KGaA.

•	 Liang, C. 2011. “Carbon/Sulfur Nanocomposites and Additives for High-Energy Lithium 

Sulfur Batteries.” Presented at the 2011 Hydrogen Program and Vehicle Technologies 

Program Annual Merit Review and Peer Evaluation Meeting, Arlington, Virginia, May 

9–13.

•	 Liang, C. 2011. “Advanced Materials for Li-S Batteries.” Presented at the 4th Symposium on Energy Storage: Beyond Lithium Ion, Richland, Washington, June 7–9.

Publications
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Highlights

In Situ Electron Microscopy of 

Electrical Energy Storage Materials

ORNL has developed an electrochemical 

cell capable of performing in situ microscopy experiments. Before now, there were 

no high resolution electrochemical characterization techniques that can be used 

to directly observe dynamically evolving 

electrochemical reactions during charge/

discharge cycling in volatile battery electrolytes. This technique has allowed ORNL 

to study the formation and growth of the 

solid electrolyte interphase on graphite 

electrodes in real time and at high spatial 

resolution. 

Understanding how interfaces—particularly electrode-electrolyte solid-liquid 

interfaces—control the physical and electrochemical energy conversion processes 

is a critical challenge in the accelerated 

development of materials used in electrical 

energy storage systems. For example, 

in lithium ion–based systems, when the 

liquid electrolyte decomposes, a passive 

multiphase layer grows at the electrodeelectrolyte interface. Once formed, this 

solid electrolyte interphase (SEI) protects the active electrode materials from 

degrading and regulates the transport 

and intercalation of lithium ions during charge/discharge cycling. Due to 

the dynamically evolving nature of this 

nanometer-scale interface, it is difficult 

to design experiments that will not only 

elucidate the fundamental mechanisms 

controlling SEI nucleation and growth, 

but will also track the microstructural 

and chemical evolution of the SEI as a 

function of charge/discharge cycling to 

be monitored in real time.

(a) Scanning electron microscopy micrograph of battery electrodes [highly oriented pyrolytic 

graphite (HOPG) anode and lithium cobalt oxide cathode] attached to the biasing microchips and 

across the silicone nitride membrane, (b) charging curve, (c) bright-field TEM image of HOPG 

anode before experiment, and (d) snapshot acquired during in situ electrochemistry experiment 

depicting the formation of the SEI on the surface of the graphite anode.
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The in situ electron microscopy technique, 

which uses an electrochemical cell holder 

built specifically for in situ transmission 

electron microscopy (TEM) characterization, will enable scientists to evaluate critical nanometer-scale microstructural and 

microchemical changes as a function of 

test conditions, electrode materials, electrolytes, and electrolyte additives. Preventing the evaporation of high vapor pressure 

and volatile organic liquid electrolytes 

has been a major challenge that has been 

overcome by sealing fluid between thin 

electron transparent viewing membranes. 

To create the electrochemical cell, two 

silicon microchips are stacked upon one 

another and placed within the tip of a 

precision-machined TEM holder. Biasing 

contacts are deposited onto the lower 

chip or “window” of the cell, which also 

serves as a platform for attaching battery electrodes and for interfacing with an 

external potentiostat for electrochemical 

testing. A 500 nm spacer material patterned on the upper chip controls the 

thickness of the liquid electrolyte layer in 

the cell. The cell incorporates a liquid delivery system (microfluidic syringe pump 

and microfluidic tubing) to allow liquid 

electrolyte to flow between the silicon 

nitride membranes that make up the cell. 

The TEM holder was built specifically for 

the Hitachi HF3300 S/TEM at the ORNL 

ShaRE User Facility, which is equipped 

with imaging detectors and a Gatan GIF 

Quantum for electron energy loss spectroscopy and energy-filtered TEM. 

•	 Unocic, R. R., et al. 2011. “The Versatility of In-Situ Environmental Fluid Cells for Materials Science Research.” Presented at Materials Science & Technology 2011, Columbus, Ohio, October 16–20.

•	 Unocic, R. R., et al. 2011. “Use of In-situ TEM Characterization to Probe Electrochemical Processes in Li-ion Batteries.” Presented at 2011 Materials Research Society 

Spring Meeting and Exhibit, San Francisco, California, April 25–29.

•	 Unocic, R. R., et al. 2010. “In Situ TEM Characterization of the SEI in Li-ion Batteries.” 

Presented at the 218th Electrochemical Society Meeting, Las Vegas, Nevada, October 

10–15. 

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Highlights

Study of Local State of Charge and 

Underlying Structures in Lithium 

Battery Electrodes

An ORNL-led research team consisting 

of scientists from ORNL and Ford Motor 

Company are using combined confocal 

micro-Raman imaging and electron microscopy for studying lithium ion electrodes 

subjected to various state of charge (SOC) 

and stress cycles. This study will provide 

important insights into cycle-life and voltage depression issues in lithium-rich manganese nickel cobalt (MNC) compositions, 

and correlate electrochemical performance 

with microstructural phase changes. 

Key challenges with lithium-rich compositions are that they have a very high 

first cycle irreversible capacity loss 

upon high voltage cycling, and undergo 

structural transition upon repeated high 

voltage cycling (more than 4.6 V). They 

also have very limited rate capability 

because of the lower intrinsic electronic 

and ionic conductivity. Accomplishments 

include doubling the rate performance 

for lithium-rich MNC obtained from 

Toda America Inc. and successful elecRaman maps showing local SOC variation across NCA electrodes cycled at 4.1 V under constant current condition at 3-C rate with 1 hour potentiostatic step. SOC plots show the local inhomogeneity 

across the electrode surface and could vary under electrochemical conditions.
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trochemical benchmarking of lithium-rich 

composition to address the issue of voltage 

suppression.

The project team monitored SOC variations 

on the surface of commercial lithium nickel 

cobalt aluminum oxide (NCA) electrodes 

subjected to various charge-discharge 

protocols. A battery’s SOC is a macroscopic indicator of the amount of its stored 

energy and is often used as a diagnostic 

tool for observing battery performance. The 

microscopic origin of the SOC in connection to lithium ion electrodes is related to 

the local lithium content (or lack of it) in 

the individual electrode particles. Commercial electrodes for lithium ion batteries are composite materials composed of 

active electrode material, polymeric binders, and carbon diluents. At an electrode 

level, the local SOC could be nonuniform 

with variations becoming more apparent as 

the cell degrades, resulting in either power 

fade, capacity fade, or both. Understanding the spatial variation of SOC on 

the electrode surface could provide a 

microscopic picture of the degradation 

occurring at a local scale. 

As mentioned above, the team carried 

out ex situ Raman mapping of electrodes that have been electrochemically 

cycled under different conditions. Using 

a particle-level SOC, the team obtained 

an SOC Raman map showing electron 

distribution at a micron-length scale. 

The ex situ SOC map is expected to 

change as the electrodes are cycled at 

different rates and under extreme duty 

cycle conditions. This provides a statistical means for studying the micron-scale 

SOC variation of commercially fabricated electrodes to identify key failure 

modes at the electrode (or materials) 

level that affect the cycle life of the 

lithium ion cell. 

•	 Nanda, J., et al. 2011. “Observation of Local State of Charge Distributions in Lithiumion Battery Electrodes.” Adv. Funct. Mater. 21:3282–3290. 

•	 Varadaraajan, Vikram, et al. 2011. “Direct Synthesis of Nanostructured V2O5 Films 

using Solution Plasma Spray Approach for Lithium Battery Applications.” J. Power 

Sources 196(24):10704–10711.

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Highlights

Mechanical Degradation 

of Electrodes

The role of mechanical degradation in 

lithium ion battery lifetime and capacity fade is not thoroughly understood. 

Research has been limited by the parameters of available characterization 

techniques. A better understanding is 

important to the development of nextgeneration lithium ion (Li-ion) batteries. 

ORNL has developed a laboratory-scale 

method for using acoustic emission (AE) 

and x-ray diffraction (XRD) to monitor 

degradation in Li-ion batteries that will 

enable the development of cost effective in situ characterization tools. In situ 

AE-XRD is safe, uses inexpensive components, and is adaptable for either anode 

or cathode materials, making it a useful 

method for a wide variety of situations. 

AE is used to detect, sort, and classify mechanical events such as particle 

fracture inside cycling Li-ion batteries. 

Special in situ methods of XRD are used 

to directly correlate the observed fracture 

events with strain in the active materials. 

Changes in electrode materials—lattice 

strain and phase transformation in cathodes (nickel-manganese-cobalt, manganese oxide, and Li1.2Ni0.15Mn0.55Co0.1O2) 

and tin anodes—were measured and correlated well with the observed AE activity.

ORNL’s novel beryllium-free in situ AEXRD cell uses a metalized Mylar or 

Kapton window to allow x-ray penetration 

during cycling in standard coin cell hardware. This technique provides a safe, inBar graph of AE activity for each charge and discharge step. 

A clear majority of events were observed during charging, 

and a fatigue-type AE activity onset was seen.
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expensive alternative to current in situ XRD 

methods. It also provides data for a depth 

of understanding that before was possible 

only with special miniature cells and very 

short synchrotron beam time. The new cell 

allows for extended beam time in inexpensive laboratory-scale diffractometers. Mylar 

or Kapton disks sputtered with compatible 

metals can be used in direct contact with 

active materials. AE-XRD will enable further 

fundamental understanding of material 

degradation mechanisms and their correlation with capacity fade and cell failure.

•	 Rhodes, Kevin, et al. 2011. “Evolution of Phase Transformation Behavior in 

Li(Mn1.5Ni0.5)O4 Cathodes Studied by In Situ XRD.” J. Electrochem. Soc. 158(8):A890–

A897.

•	 Rhodes, Kevin, et al. 2011. “Novel Cell Design for Combined In Situ Acoustic Emission 

and X-Ray Diffraction Study During Electrochemical Cycling of Batteries.” Rev. Sci. 

Instr. 82:075107.

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Highlights

Study Charts the Impacts of 

Intermediate Ethanol Blends on 

Vehicle Emissions

Fuels

ORNL has been working with the National 

Renewable Energy Laboratory and others 

to assess the viability of using intermediate ethanol blends—blends of gasoline 

with up to 20 vol % ethanol—in conventional vehicles to meet energy needs, 

decrease U.S. reliance on petroleum products, and meet U.S. goals for using renewable fuels. In 2011 the research team 

completed a groundbreaking study on the 

effects of intermediate blends on vehicle 

emissions and emissions systems.

The study, which was unprecedented in 

size and scope, included 82 vehicles (both 

cars and light trucks) from the 6 largest 

vehicle manufacturers, and new and preowned vehicle models from 2000 through 

2009. Vehicles were acquired to establish matched sets of two, three, or four 

vehicles of each model being tested, and 

each vehicle of a set was dedicated to a 

specific gasoline-ethanol blend for aging. 

Vehicles were aged using the U.S. Environmental Protection Agency’s Standard 

Road Cycle, the official driving cycle for 

aging studies to assess exhaust system 

durability, and emissions were tested periodically throughout the program. Emissions tests on all vehicles were conducted 

using emissions certification gasoline 

(E0—i.e., no ethanol) and splash blends 

of this same fuel with denatured ASTM 

D4806 ethanol to produce “certification 

Median change in fuel economy and carbon monoxide 

(CO), nitrogen oxides (NOx), non-methane hydrocarbon 

(NMHC), non-methane organic gas (NMOG), and methane 

(CH4) emissions relative to ethanol-free gasoline. Range 

bars show interquartile range (25th to 75th percentile). 

Results for Federal Test Procedure at start-of-test.
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grade” E10, E15, and E20. In addition to 

emissions testing, powertrain component 

inspections were also performed on six of 

the vehicle sets at the end of the program.

Data analysis on the full suite of vehicle 

data was completed in 2011, and the entire project has been detailed in a comprehensive report, Intermediate Ethanol Blends 

Catalyst Durability Program. In general, 

emissions increased with increasing mileage accumulation for all vehicles, whether 

aged on ethanol blends or ethanol-free 

gasoline, and aging with ethanol blends 

did not affect emissions changes over time 

differently than aging with ethanol-free 

gasoline. The examination of the powertrain components showed no signs of 

increased corrosion or wear from the use 

of ethanol blends compared to gasoline. 

Vehicles aged with ethanol blends did 

have higher intake valve deposit mass, 

however, detergent additive concentrations were not adjusted in consideration 

of adding ethanol to the fuel.

The information from this study has 

already been used by the Environmental Protection Agency to grant a partial Clean Air Act waiver1,2 allowing 

increased ethanol in gasoline, and it is 

anticipated that the study and its accompanying report will have even more 

far reaching effects in the future.

•	 Shoffner, Brent A., et al. 2012. Powertrain Component Inspection from Mid-Level Blends 

Vehicle Aging Study. Prepared by Southwest Research Institute for Oak Ridge National 

Laboratory, November 2010. ORNL/TM-2011/65, Oak Ridge National Laboratory, Oak 

Ridge, Tennessee.

•	 West, B. H., et al. 2012. Intermediate Ethanol Blends Catalyst Durability Program. ORNL/

TM-2011/234, Oak Ridge National Laboratory, Oak Ridge, Tennessee. 

1“Partial Grant and Partial Denial of Clean Air Act Waiver Application Submitted by Growth Energy To Increase 

the Allowable Ethanol Content of Gasoline to 15 Percent; Decision of the Administrator.” Federal Register 

75(213), November 4, 2010, pp. 68094–68150.

2 “Partial Grant of Clean Air Act Waiver Application Submitted by Growth Energy To Increase the Allowable 

Ethanol Content of Gasoline to 15 Percent; Decision of the Administrator.” Federal Register 76(17), January 

26, 2011, pp. 4662-4683.

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Highlights

Effects of Alternative Fuels on 

EGR System Performance

Greater use of alternative, non-petroleumbased fuels is heavily dependent on increased understanding of their effects on 

conventional automotive systems. ORNL 

researchers are working to quantify the 

effects of non-petroleum-based fuels on 

exhaust gas recirculation (EGR) system 

performance and to identify fuels or fuel 

properties that may reduce the effectiveness of EGR systems through fouling, or 

problematic deposits on EGR coolers.

As has been mentioned elsewhere in 

this report, EGR is a key aspect of many 

advanced combustion technologies and 

has become a mainstay for controlling 

nitrogen oxide (NOx) emissions in diesel 

engines. Fouling of the EGR cooler by 

hydrocarbons and particulate matter 

from the exhaust gas stream can reduce 

the performance of the cooler in a matter 

of hours, causing the temperature of the 

EGR stream to rise and potentially producing higher NOx emissions. 

Some non-petroleum-based fuels (for example, biodiesel) have unique fuel chemistries and/or combustion behavior that 

may cause changes in the fouling tendencies of EGR coolers. If this is found to be 

the case, it represents a very significant 

technical hurdle that must be overcome 

if these fuels are to achieve significant 

market penetration. The first step toward 

overcoming this potential hurdle is to gain 

a better understanding of the scope of the 

problem, which ORNL is doing through experiments using an engine and sampling 

system with surrogate EGR cooler tubes to 

examine the nature of the deposits caused 

by operation with non-petroleum-based 

fuels. 

In 2011 a series of experiments was conducted to determine the effect of various 

surface treatments on EGR deposits under 

both transient and steady state flow conditions. The results showed that surface 
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treatments do not have a significant impact 

on fouling and thus do not represent a 

means of avoiding the cooler fouling issue. 

Furthermore, the transient flow experiments 

demonstrated that deposit removal requires 

high gas flow rates that may be a challenge 

in practical EGR systems.

Experiments aimed at further understanding 

the impact of non-petroleum-based fuels 

on the EGR fouling process are planned in 

the coming year. These studies will focus on 

separating the conditions that may generate 

plugged coolers from those that produce 

more frangible layers, and further investigation of the potential role of fuel-related 

hydrocarbons on the stability of the deposit 

layer.

•	 Storey, J. M. E., et al. 2011. “Exhaust Gas Recirculation Cooler Fouling in Diesel Applications: Fundamental Studies, Deposit Properties, and Microstructure.” Presented at 

the 2011 Eurotherm Heat Exchanger Fouling and Cleaning Conference, Crete Island, 

Greece, June 5–10.

•	 Styles, D., et al. 2010. “Factors Impacting EGR Cooler Fouling—Main Effects and 

Interactions.” Presented at the 2010 Directions in Engine Efficiency and Emissions 

Research (DEER) Conference, Detroit, Michigan, September 27–30.

•	 Lance, M., S. Sluder, S. Lewis, and J. Storey. 2010. “Characterization of Field-Aged 

EGR Cooler Deposits.” SAE Int. J. Engines 3(2):126–136.

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Highlights

Enabling High-Efficiency 

Ethanol Engines

As part of a multiyear Cooperative Research and Development Agreement, researchers at ORNL and Delphi Automotive 

Systems have been investigating methods 

to remove barriers to more widespread 

use of ethanol and ethanol blends in the 

United States. Prior years’ efforts focused 

on identifying and demonstrating potential efficiency gains for ethanol fuels. 

The effort in 2011 was focused on determining the effect of ethanol content on 

particulate emissions in a gasoline direct 

injection (GDI) engine relative to gasoline 

and port fuel injection (PFI) fueling. PFI 

has been the standard in spark ignition 

engines for the last 20 years but is being eclipsed by GDI because it promises 

increased fuel efficiency and power while 

controlling emissions levels. However, 

expected changes in regulations for 

particulate emissions make it essential 

to understand the impact of fuel compositions on particulate emissions under 

different fueling regimes.

The research platform used for this 

research was a multicylinder production 

engine modified by Delphi to make it 

capable of optimization for E85. The engine was also modified for PFI, allowing 

direct comparison of particle emissions 

at the same engine load on a common 

engine with two different fueling strategies. Engine operation focused on a 

single operating point at 1,500 rpm and 

8 bar brake mean effective pressure—a 

Particle emissions for conventional 

gasoline, E20, and E85 under 

throttled operation at 1,500 rpm, 8 

bar indicated mean effective pressure, and a fuel injection timing of 

320 crank angle degrees before 

top dead center. Under these conditions E20 produced the highest 

concentration of particle emissions, followed by conventional 

gasoline and E85. The differences 

between conventional gasoline and 

E20 were dependent on the fueling 

and breathing strategies, with E20 

producing highest particle emissions under some conditions and 

conventional gasoline producing 

the highest emissions at other conditions. In all cases, however, E85 

produced by far the lowest concentration of particle emissions.
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condition known to produce high smoke 

(particulate) emissions. The engine was 

operated with gasoline, E20, and E85.

The main finding of the 2011 campaign 

was that use of E85 results in a reduction in particulate emissions of up to 2 

orders of magnitude relative to GDI fueling 

with gasoline and E20. Furthermore, GDI 

particulate emissions with E85 are similar 

to those for PFI fueling with gasoline. Thus, 

an increase in particulate emissions beyond that of PFI engines can be prevented 

while gaining the efficiency of GDI engines 

using E85.

Four-cylinder research engine modified from a 

production engine by Delphi.

•	 Szybist, J. P., et al. 2011. “Ethanol Blends and Engine Operating Strategy Effects on 

Light-Duty Spark- Ignition Engine Particle Emissions.” Energy & Fuels 25(11):4977–

4985.

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Highlights

Investigation of Impacts of 

Emerging Fuels and Lubricants 

on Emissions Control Devices

To enable use of alternative fuels and advanced lubricants, it is critical to evaluate 

their compatibility with emissions control 

devices. ORNL researchers are working with 

industry partners to investigate the impact 

of emerging fuels and lubricants on emissions control devices using accelerated 

aging techniques. A key element of this 

research is the development of (1) protocols for accelerated aging and poisoning of 

emissions control devices and (2) laboratory experiments that accurately mimic field 

use. Such protocols do not exist for current 

emissions control devices, and their development will enable more rapid implementation of new fuel and lubricant formulations 

and improvements in the emissions control 

devices being developed. 

Biodiesel fuel, a domestic renewable 

energy source synthesized from vegetable oil or animal fat, combusts similarly 

to diesel fuel; however, greater use has 

been hampered by unknowns such as 

the impact on emissions control devices. 

One particular concern is the potential 

effect of the trace elements of sodium 

and/or potassium in biodiesel. (The 

American Society for Testing and Materials specifies a maximum of 5 ppm combined sodium and potassium in biodiesel.) To address this concern, efforts in 

2011 focused on a comparison of selective catalytic reduction catalysts [SCR, 

used for nitrogen oxides (NOx) control 

in conjunction with ammonia/urea] and 

diesel particulate filters (DPF, used for 

SCR NOx reduction performance illustrating the impact of Na in the DOC-SCR-DPF arrangement compared to the minimal effects when the DPF is in front of the SCR (DOC-DPF-SCR). 
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particulate emissions control) exposed to 

sodium in the emissions control device 

configurations used in light duty vehicles 

[diesel oxidation catalyst (DOC)-SCR-DPF] 

and heavy duty vehicles (DOC-DPF-SCR). 

The results showed that while sodium can 

significantly impact SCR catalysis, placing 

the DPF in front of the SCR protects the 

catalyst from sodium and its effects. Some 

protection from thermal stresses is also 

gained by this placement. Placement of the 

DPF in front of the SCR, however, led to significant sodium penetration of the cordierite 

wall of the DPF, which other studies have 

shown to affect the strength of the DPF. The 

location of the sodium contamination in the 

accelerated aged samples mimicked that 

seen in long-term engine aged catalysts, 

suggesting the accelerated aging protocol is valid. 

Based on these results, a large collaboration was formed between ORNL, the 

National Renewable Energy Laboratory, 

National Biodiesel Board, the Manufacturers of Emission Controls Association, 

and Ford Motor Company to determine 

appropriate limits for trace amounts of 

sodium in biodiesel. 

•	 Brookshear, D. W., et al. 2011. “Investigation of the Effects of Biodiesel-Based Na on 

Emissions Control Components.” Catalysis Today (forthcoming). Available online January 24, 2012. doi:10.1016/j.cattod.2011.12.001.

•	 Ottinger, N. A., et al. 2011. “Effect of Lean/Rich High Temperature Aging on NO Oxidation and NOx Storage/Release of a Fully-Formulated Lean NOx Trap.” Applied Catalysis 

B: Environmental 101(3–4):486–494.

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Highlights

High Temperature Materials Laboratory

The ORNL High Temperature Materials Laboratory (HTML), a DOE User 

Facility dedicated to solving materials problems, presents scientists and 

students with unique opportunities for collaborative world-class research. 

The HTML is dedicated to solving materials problems that limit the efficiency and reliability of systems for power generation and energy conversion, distribution, and use. A particular focus is the development of 

materials based, energy efficient, and environmentally friendly transportation technologies that will enable the United States to use less petroleum. 

HTML’s six user centers—Diffraction, Materials Analysis, Mechanical Characterization and Analysis, Residual Stress, Thermography and Thermophysical Properties, and Tribology Research—are clusters of specialized 

equipment designed for specific types of property measurements. They 

provide users with extensive capabilities for characterizing the microstructure, microchemistry, and physical and mechanical properties of materials over a wide range of temperatures. HTML also manages a neutron 

beam line facility at the ORNL High Flux Isotope Reactor, and a synchrotron beam line at the National Synchrotron Light Source at Brookhaven 

National Laboratory. 

A reciprocating tribometer is used to measure the friction forces between 

battery materials during repeated charging and discharging.
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In addition to the physical facilities, HTML User Program participants also 

have access to HTML’s professional staff who: 

•	 participate in the planning, performance, and interpretation of research, 

including co-preparation of technical papers and presentations from 

nonproprietary research;

•	 assist users in the safe and efficient operation of user center research 

equipment; and

•	 maintain instruments to maximize their availability for research.

A mechanical testing machine used to 

characterize the stress-strain response of 

various battery materials.
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Highlights

General Motors Analyzes Lithium Ion 

Battery Performance with Customized 

Neutron Scattering Technique

Researchers from the GM R&D Center in 

Warren, Michigan, and the HTML User Program have developed a customized nondestructive monitoring technique for analyzing 

the large format lithium ion batteries used in 

GM’s electric vehicles. Using neutron scattering and high resolution infrared imaging, 

they conducted in situ analysis of cathode 

and anode materials inside fully functioning 

lithium ion cells. Baseline data were collected on internal volume changes, surface 

temperature changes, and distribution of 

active materials during charging and 

discharging. One of the technical barriers to overcome in the neutron scattering 

study was extracting small electrode-related signals from the large background 

signals from polymer-based pouch and 

separator materials. Using ORNL’s High 

Flux Isotope Reactor and special features in scanning selected 2θ angles (6 

degrees) at the HB-2 beam line, characteristic diffraction changes associated 

with electrode materials were monitored 

successfully. 

Plots of a GM 15-Ah cell from this 

project showing the fully charged 

state (open circuit voltage, VOC

= 4.15 V) in dark blue and state 

of charge at the midpoint of 

discharge (VOC = 3.85 V) in red, 

as a function of time: a) before 

discharging and b) during discharging. Insets at lower left are 

neutron intensity vs 2θ scans. 
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The infrared in situ imaging captured 

small changes in temperature at critical 

stages and locations, while the neutron scattering experiments confirmed 

charge/discharge cycle models. The 

techniques used in this project are a significant advance over conventional tools 

and techniques and will be applicable in 

other research projects. The information 

obtained during the project will help GM 

ensure that the performance of production batteries is consistent with that 

predicted from laboratory studies.

Dr. Yang prepares to load a large format lithium 

ion cell for testing. 
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Highlights

Residual Stresses in Turbocharger 

Shaft-Wheel Assembly Welds

Honeywell Turbo Technologies visited the 

HTML as part of a two-pronged study to 

better understand residual stresses in the 

weld joints of turbocharger shaft wheel 

assemblies (SWAs). Honeywell researchers 

conducted neutron and x-ray scattering 

characterization studies of stress relief 

methods applied during the manufacturing 

process. One element of the experimental 

plan was to create a map of the residual 

strains in the region near the electron 

beam (EB) weld joining the shaft to the 

turbine wheel in both through-thickness 

and circumferential directions using the 

HTML second generation neutron residual 

stress facility (NRSF2). NRSF2’s combination of small gauge volumes (1.5 × 1.5 × 

0.5 mm) and good intensity made these 

through-thickness measurements feasible. The deep penetration that only neutrons provide was critical for the study 

of stresses near the EB weld. The team 

observed significant changes in hoop and 

radial strains around the circumference, 

localized within a 30° angular range of 

the as-welded sample and the standard 

“stress relieved” SWAs. These changes 

show that the industry’s standard manufacturing method is not fully effective in 

relieving residual stresses from the EB 

weld operation. Measurements on an 

SWA subjected to 1100°C furnace stress 

relief showed that effectively all residual 

stresses were relieved and no localized 

stresses remained.

Honeywell SWA mounted on the NRSF2 

beam line sample stage.
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The second element of the study was 

to quantify defect density by mapping 

the near-surface residual stresses and 

peak breadth along the shaft in the two 

bearing regions. X-ray diffraction (XRD) 

measurements of surface stresses were 

made at the bearing regions along the 

shaft. Mapping data were collected using the new PROTO l XRD instrument on 

SWAs in three conditions: as-welded, 

standard stress relieved, and furnace 

treated at 1100°C. Analysis of the XRD 

data confirmed the neutron scattering results that showed furnace heat 

treatment removed stresses caused by 

welding.

Turbochargers are key elements in advanced fuel-efficient engines, so ensuring 

their reliability is important to manufacturers of these engine boosters. Quantifying the role that residual stresses play in 

the lifetime of the SWA and turbocharger 

housings will aid Honeywell in designing 

the highest quality SWAs and monitoring 

manufacturing processes. Planned future 

collaborations with Honeywell include the 

evaluation of cost-effective ways to mitigate residual stress and thereby extend 

component life and ensure reliability of 

both the SWA and turbine housing in the 

company’s turbochargers. 

Neutron circumferential strain mapping of SWA showing 

variation of hoop strain at two distances from weld.
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Highlights

Magnesium Elektron Characterizes 

Magnesium Sheet Alloy Materials 

to Produce Improved Automotive 

Structures

Magnesium Elektron North America 

researchers came to HTML to work on 

a user project focused on two goals: enhancing formability of sheet alloys and 

producing lighter weight automotive 

components. Experimental data were 

collected to help determine the manufacturing process adjustments needed 

to improve magnesium sheet formability. X-ray diffraction of crystallographic 

texture data from heated, asymmetrically rolled AZ31B and ZEK100 sheet show 

the orientation of the (002) pole is out 

of plane after asymmetric rolling (see 

figure below). That is, after asymmetric 

rolling the majority of basal planes are 

no longer parallel to the plane of the 

sheet, which is important for formability 

purposes. The microstructure and microtexture of the two magnesium alloys 

as a function of hot working were also 

investigated with electron backscatter 

diffraction (EBSD) microscopy. Different 

grain orientations by color, as well as the 

presence of shear bands (linear features 

cutting across grains) are shown in the 

figure on the right. With higher levels of 

deformation, the density of shear bands 

increased and more deformation twinning was observed. 

Characterization results from both electron backscatter and x-ray diffraction will 

enable Magnesium Elektron to design 

manufacturing processes for large-scale 

production of magnesium alloys for automotive structures. 

Three-dimensional x-ray pole figures plotting intensity of the (002) or basal planes 

as a function of azimuthal and tilt angle for the asymmetrically rolled AZ31B.
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EBSD image showing the microstructure and microtexture of 

ZEK100 asymmetrically rolled at 150°C after a 5% reduction. The 

inverse pole figure map (inset) provides a key to the color-crystallographic orientation relationship.

•	 Randman, D., et al. 2011. “The Effect of Rare Earth Elements on the Texture and Formability of Shear Rolled Magnesium Sheet.” Magnesium Technology 2011, edited by W. 

H. Sillekens, S. R. Agnew, N. R. Neelameggham and S. N. Mathaudhu. Hoboken, New 

Jersey: John Wiley & Sons.

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Highlights

Investigating Fatigue Crack Growth 

in High-Strength Magnesium Alloy

The first comprehensive study of small 

fatigue crack propagation behavior in a 

magnesium alloy subjected to various 

thermomechanical heat treatments was 

undertaken by Michigan State University in an HTML user project. Magnesium alloys are lightweight alternatives 

to structural alloys used in engine and 

other automotive components, but their 

low fatigue strength and high cost has 

inhibited widespread use. Michigan State 

has been studying the small fatigue crack 

growth behavior of a high-strength nanoMAG AM60 magnesium alloy subjected 

to various thermomechanical processing 

treatments. They partnered with the HTML 

User Program to characterize the effects 

of thermomechanical processing and 

subsequent heat treating on the fatigue 

crack growth behavior of a Thixomolded® AM60 magnesium alloy. Notches 

a few hundred microns in size were 

machined on test specimens, and the 

growth behavior of small fatigue cracks 

emanating from the notches was directly 

measured using a telescopic system 

recently installed at HTML. The effect 

of mechanical loading parameters such 

as maximum stress and load ratio on 

the small fatigue crack growth behavior 

was also determined. The interactions 

of the small fatigue cracks with porosity 

and other material defects were found 

to determine the overall fatigue lifetime, 

while the role of grain size was found to 

be secondary across the various thermomechanical treatments investigated. 

Michigan State’s Zhe Chen examines a microscope image of a 

fatigue crack in an AM60 magnesium alloy sample subjected to 

the Thixomolded® thermomechanical processing heat treatment. 
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The results of this project can be used 

directly to estimate fatigue life for the 

different heat treatments under various 

mechanical loading conditions. In addition, 

Michigan State will use the results of its investigation to support development efforts 

at Thixomat, Inc., owner of the Thixomolding® manufacturing process, for a new 

product line aimed at replacing existing 

aluminum alloys with magnesium alloys for 

automotive light-weighting applications.

•	 Chen, Z., et al. 2011. “The Effect of Thermomechanical Processing on the Creep 

Behavior and Fracture Toughness of Thixomolded® AM60 Alloy.” Magnesium Technology 2011, edited by W. H. Sillekens, S. R. Agnew, N. R. Neelameggham, and S. N. 

Mathaudhu. Hoboken, New Jersey: John Wiley & Sons.

•	 Chen, Z., et al. 2011. “The Small Fatigue Crack Growth Behavior of an AM60 Magnesium Alloy.” Presented at the Materials Science & Technology 2011 Conference & 

Exhibition, Columbus, Ohio, October 16–20. 

Close up look at the microscope image of a fatigue crack in an 

AM60 magnesium alloy sample subjected to the Thixomolded® 

thermomechanical processing heat treatment. 

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Highlights

Influence of Molding Processes 

on Properties of Glass Fiber–

Reinforced Polymers

In the first Toyota Research Institute of 

North America user project at the HTML, 

Toyota is undertaking a project to characterize the microstructure and mechanical 

properties of glass fiber–reinforced thermoplastics. These materials can reduce 

vehicle weight and improve fuel efficiency 

without sacrificing safety. In particular, 

Toyota wants to understand the influence 

of different molding processes on the 

structural properties of glass fiber–reinforced polymers. These materials may be 

produced using injection molding, injection compression, compression, or direct 

injection techniques. Each process results 

in different material microstructures and 

properties and carries a different production cost. Optical and x-ray tomography 

methods were used to measure length 

distribution, orientation, and dispersion of 

fibers. This work resulted in the first successful correlation of optical and computed 

tomography fiber orientation measurement results on these materials. Tensile 

properties of these materials at various 

strain rates were also evaluated to assess 

the effect of microstructure on mechanical 

properties.

Discontinuous fiber thermoplastic composites are low cost, recyclable, lightweight 

materials with increasing use in automotive 

applications. Understanding microstructure 

and its influence on material properties is 

critical for proper design and application 

of these materials to achieve the goals of 

the DOE Vehicle Technologies Program. 

Increased use of lightweight thermoplastic composite materials will contribute to 

reaching the target of a 50% reduction in 

vehicle weight. 

Cross section of material showing discontinuous glass fibers in 

quasi-random orientation (diameter 15 μm).
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•	 Gandhi, U., S. DeBoodt, and V. Kunc. 2011. “Investigation of Fiber Orientation in Fiber 

Reinforced Polymers.” Presented at Digimat Users’ Meeting 2011, Munich, Germany, 

October 10–12.

Umesh Ghandi, Toyota Research Institute, prepares a tensile sample 

for high strain rate tensile testing with digital image correlation.

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Highlights

Lightweight Materials

Low Cost Carbon Fiber 

Development

In efforts to produce lighter weight vehicles and achieve corresponding gains in 

fuel economy, ORNL and DOE are taking a 

multipronged approach aimed at making 

carbon fiber (CF) more attractive to manufacturers. The major barrier to greater use 

of CF is its cost. Fifty-one percent of the 

cost of producing CF is attributable to the 

precursor, and 39% to conversion of the 

precursor into CF. A significant amount of 

the ORNL effort has been devoted to developing lower cost precursors and lower 

cost, higher rate production technologies. 

•	 ORNL’s successful collaboration with 

fiber manufacturer Fibras Sineticas de 

Portugal S.A. (FISIPE) to render textilebased polyacrylonitrile (PAN) suitable 

for conversion to CF is nearing completion. Textile PAN sells for about half 

the cost of conventional CF precursors. ORNL and FISIPE developed an 

alternative pretreatment for the textile 

PAN, which was installed in a FISIPE 

production facility. It was verified that 

the CF produced met or exceeded 

strength and modulus requirements. 

Commercialization plans are in development.

•	 Melt spun polyolefins are the lowest 

cost potential precursors due to low 

raw material cost, simpler spinning 

process, and inherently high carbon content. During 2011, greater 

understanding of the mechanical 

properties of polyolefin precursors 

and their relation to processing 

parameters was achieved, and previously identified issues of incomplete 

functionalization of the fiber core and 

interfilament bonding during thermal 

treatment were successfully resolved. 

A polyolefin based CF with a tensile 

strength of 237 Ksi was produced, 

while a different sample yielded a 

modulus of 17.2 Msi. In FY 2012 

work will continue on enhancing the 

Breakdown of CF production costs (Base diagram courtesy of Harper International.)
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properties to meet the program targets 

of tensile strength of at least 250 Ksi 

and modulus of at least 25 Msi. 

•	 To decrease conversion costs, ORNL has 

developed a new plasma based process 

resulting in oxidation times of as little 

as 20 minutes for aerospace grade PAN 

(compared to 90–120 minutes for conventional processing) and 45 minutes 

for the first samples of textile grade 

PAN. All mechanical property requirements were met except for modulus (5% 

under minimum). The research team is 

optimizing the new process for textile 

grade fibers. In addition, the team completed exhaustive fiber damage analyses 

in conjunction with mechanical properties analyses of aerospace grade PAN 

processed with the advanced oxidation 

process. The project team is currently 

completing the work necessary to design a larger oxidation reactor for installation in the ORNL Small Pilot Line. 

•	 Hunt, Marcus A., et al. 2012. “Patterned Functional Carbon Fibers from Polyethylene.” Advanced Materials. First published online: March 21, 2012. dol: 10.1002/

adma.20110455/1. 

•	 Warren, C. David. 2012. “Low Cost Carbon Fiber Development—Oak Ridge National 

Laboratory.” Lightweight Materials FY 2011 Annual Report. DOE/EE-0674. U.S. Department of Energy, Washington, D.C.. 

Textile tow precursor as produced by FISIPE and supplied to 

ORNL on spools for evaluation. 

Note the golden color of this precursor fiber, which is indicative 

of the specialized pretreatment 

that was developed and implemented by ORNL and FISIPE.

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Highlights

Predictive Models for Long Fiber 

Thermoplastic Injection Molding

Long-fiber reinforced thermoplastics 

have generated interest in the automotive industry due to their low cost, rapid 

production, and good mechanical properties. However, use of these materials has 

been limited by an inability to accurately 

predict their stiffness, strength, longterm durability, and service life. A collaborative program between ORNL and 

Pacific Northwest National Laboratory 

(PNNL) has been conducting research to 

address this by developing, implementing, and validating models for injection 

molding and property prediction, allowing complete prediction from process to 

property in as-formed components.

Validation of the predictive models was 

completed for two dimensional geometries in fiscal year 2011. Large plaques 

were molded using materials representative of the automotive industry—polypropylene/40% and PA6,6/40% glass. Radial 

and linear flow was achieved by center 

gating and edge gating of samples. To 

change the microstructure of the resulting material and exercise the predictive 

models, fill speed and back pressure were 

varied. Experimental data measured for 

the plaques point to consistent material 

properties, including appropriate dispersion, lack of weld lines in sample regions, 

and an entangled fiber network with a 

relatively wide core. Therefore, the test 

data obtained are well suited for model 

validation. 

ORNL and PNNL models support prediction from process to property. Left to right: global injection molding flow prediction, global stress prediction, progressive failure prediction, and x-ray of 

failed sample. 
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Accurate prediction of fiber orientation is 

crucial for prediction of material properties. 

Three locations in each plaque type were 

evaluated experimentally and compared to 

predictions, which were performed with a 

single set of parameters for a given material. Predicted and experimental results for 

the 24 cases evaluated matched within 8% 

on average, exceeding the project target 

of 15%. The nature of flow, including the 

variation in core and shell thickness, was 

captured for all cases. Subsequent predictions of mechanical properties based on 

these orientation results further confirmed 

the high fidelity of the predictive models.

Platforms prevalent in the automotive industry were selected to commercialize the 

tools developed in this project. The injection molding models are implemented by 

Autodesk Inc. in their commercial code, 

Moldflow. Licensing by PNNL for the 

property prediction tool developed under 

the Abaqus FEA software environment of 

Dassault Systemes is in progress. Both 

tools are being tested by industry professionals.

To complete development of the tools, a 

complex three-dimensional automotive 

part was selected in collaboration with 

industry experts. Test articles will be 

molded with materials identical to those 

used for validation on plaque geometry, 

under similar processing conditions, and 

measured values will be used to validate 

the models.

Comparisons of the experimental and predicted fiber orientation results for (left) the 40% slowfill glass/PP center-gated plaque, worst case; and (right) the 40% fast-fill glass/PA6,6 centergated plaque, best case. Series designated A11 represent flow direction orientation, and series 

designated A22 represent cross-flow direction orientation.
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Highlights

High Strain Rate Characterization 

of Magnesium Alloys

Low-density magnesium (Mg) alloys are 

good candidates for lightweight automotive components to achieve significant 

vehicle weight reductions, which in turn 

enable increased fuel economy. Because 

these materials are not well characterized with regard to mechanical properties 

under impact, Mg alloy components are 

overdesigned in order to compensate for 

uncertainties in deformation and failure 

mechanisms. ORNL is addressing this 

problem by developing new methods for 

characterizing material behavior at high 

strain rates and for determining underlying mechanisms of load-induced property 

degradation. The information and models 

that result from this research will reduce 

uncertainties in component design thereby 

reducing overdesign and vehicle weight. 

Test methods, test data, and material data 

gathered during the project are available 

on the World Wide Web at

thyme.ornl.gov/Mg_new. 

The ORNL team has developed several new 

test procedures and methods that can be 

standardized for widespread use. These 

include: 

•	 New techniques to generate reliable 

tensile stress-strain data in the intermediate strain rate regime (quasistatic up to 1,000/s) corresponding to 

strain rates experienced in high speed 

forming and vehicle crashes. The tests 

are conducted on a custom-designed 

high speed servohydraulic machine 

combined with a three-dimensional 

digital image correlation method. 

For both Mg alloys tested, the yield 

strength and ultimate tensile strength 

increased slightly when the strain rate 

was increased from 1 s-1 to 1,000 s-1.

New specimen design for 

testing quasi-static shear 

strength of Mg alloy sheet.

Strain distribution of AM60B specimens with two 

different radii. Tests were conducted at nominal 

speed of 500 in./s.
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•	 A new specimen design for use in determining quasi-static shear strength 

of sheet materials, which achieves 

constraint shear strain within the shear 

ligament. Both tested Mg alloys showed 

very small strain rate sensitivity in shear. 

•	 A technique that enables measurement 

of material behavior with continuous 

strain levels and under multiple strain 

rates using a single specimen design. 

This new specimen design and testing 

procedure can produce continuously 

varying levels of plastic strain achieved 

at various locations in the specimen and 

at different strain rates. The specimen design also reduces the size of 

conventional test matrices and overall testing time and permits more 

focus on test analysis and modeling.

•	 Procedures for quantifying the 

evolving stages of damage based on 

image processing, void growth, and 

mechanical tests with the controlled 

strain application. Results show that 

void growth is dependent not only on 

the applied strain rate but also on 

the strain rate.

•	 Wang, Y., et al. 2011. “Characterization of High Strain Rate Mechanical Behavior of 

AZ31 Magnesium Alloy Using 3D Digital Image Correlation.” Advanced Engineering 

Materials 13(10):943–948. 

•	 Wang, Y., D. L. Erdman, V. Kunc, and S. Simunovic. “Material Mechanical Characterization Method for Multiple Strains and Strain Rates.” U. S. Patent Application 

61/485,163 filed May 12, 2011.

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Highlights

Understanding the Diffusion of 

Elements in Magnesium Alloys for 

use in Lightweight Components 

for Vehicles

ORNL scientists and engineers are working with an international team to develop 

a comprehensive understanding of the 

diffusion of elements in magnesium (Mg) 

alloys. The low density of Mg alloys makes 

them good candidates for lightweight 

components for use in automobiles; replacing steel chassis components with Mg 

alloys could reduce their weight by 50%, 

enabling higher fuel economy in vehicles. 

Typical Mg alloys are brittle during vehicle 

crash events and are difficult to form 

without elevated temperature processing. More ductile Mg alloys could address 

these barriers. Greater understanding of 

the diffusion of alloy elements will facilitate development of new Mg alloys with 

improved formability and ductility, and 

enable increased use of Mg in vehicles. 

Additionally, modeling precipitation and 

dissolution phenomena during heat treatment of super-vacuum die casting of Mg 

alloys requires knowledge of the diffusivities of the alloy constituents in the 

cast alloys. The Mg Integrated Computational Materials Engineering activity is 

an international effort that will result in 

an integrated suite of validated computational materials modeling tools for Mg 

alloy development. 

The team’s approach involves obtaining 

Mg tracer diffusion data using secondary ion mass spectrometry (SIMS) for 

diffusion depth profile measurements of 

stable isotopes (for example, 25Mg) in 

Mg-rich alloys. This approach is based 

on the thin film method using stable 

isotopes rather than radioactive isotopes 

as tracers, reducing the cost associated with handling and processing the 

radioisotopes and extending historic 

Arrhenius plot of the self-diffusion coefficients in pure 

Mg using the SIMS-based stable isotope thin-film technique. Comparison with an extrapolation of the published 

self-diffusion radioactive tracer data at high temperatures 

(more than 400°C) shows excellent agreement.
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radiotracer measurements to lower 

temperatures. The data for pure Mg 

self-diffusion showed very good agreement with available radioisotope tracer 

data. An ultrahigh vacuum system was 

designed and developed to minimize 

isotopic losses and provide high-purity 

isotopic thin films. New SIMS techniques 

were developed such as measurements 

on angled (less than 2 degrees taper) 

polish sections for deep diffusion depths, 

and parameters were optimized to minimize sputter roughness in polycrystalline 

samples. Interdiffusion/intrinsic diffusion experiments (involving traditional 

diffusion couples) were used along with 

thermodynamics to extract tracer diffusivities of monoisotopic elements such as 

aluminum (Al). The project has undertaken three-dimensional molecular dynamics 

modeling of volume and grain boundary 

diffusion in polycrystalline Mg alloys to 

incorporate microstructure effects. 

Work will continue in 2012 with tracer 

diffusion experiments and interdiffusion 

analysis in Mg-Al-Zn and Mg-Al-Zn-Mn 

alloys. Tracer diffusion studies are also 

planned in select rare earth and rare 

earth replacement alloys, and grain 

boundary and effective diffusion modeling 

will be extended to polycrystalline Mg-Zn 

and Mg-Al-Zn. 

•	 Brennan, S., K. Bermudez, N. Kulkarni, and Y. H. Sohn. 2011. “Growth Kinetics of 

γ-Al12Mg17 and β-Al3Mg2 Intermetallic Phases in Mg vs. Al Diffusion Couple.” In 

Magnesium Technology 2011, edited by W. H. Sillekens, S. R. Agnew, N. R. Neelameggham, and S. N. Mathaudhu, 549-552. Warrendale, Pennsylvania: The Minerals, Metals & Materials Society.

•	 Brennan, S., K. Bermudez, N. Kulkarni, and Y. H. Sohn. “Diffusion Couple Investigation of the Mg-Zn System.” In Magnesium Technology 2012, edited by S.N. Mathaudhu, N. Hort, W.H. Sillekens N.R. Neelameggham. Warrendale, Pennsylvania: The 

Minerals, Metals & Materials Society. Forthcoming. 

•	 Brennan, S., et al. “Aluminum Impurity Diffusion in Polycrystalline Magnesium.” Journal of Phase Equilibria and Diffusion. Forthcoming.

•	 Belova, I. V., T. Fiedler, N. Kulkarni and G. E. Murch. “The Harrison Diffusion Kinetics 

Regimes in Solute Grain Boundary Diffusion.” Philosophical Magazine A. Forthcoming.

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Highlights

Dynamic Characterization of 

Spot Welds in Advanced High 

Strength Steels

An ORNL team is developing a fundamental understanding of the behavior of spot 

welds in advanced high-strength steels 

(AHSSs). This project will enable more 

widespread use of AHSSs in vehicles, resulting in drastic improvements in performance while reducing vehicle weight. 

Resistance spot welding is the most common joining process used in automotive 

manufacturing, however, spot weld failure 

behavior in a dynamic crash event is not 

well understood for AHSSs. Typically there 

are several thousand spot welds in a 

vehicle, and spot weld failure can affect 

the crash response of welded structural 

components. ORNL is developing a 

spot weld modeling tool that is easy for 

engineers to use in advanced auto-body 

crashworthiness computer aided engineering. The end product will be an optimized model that can be implemented 

in crash simulation finite element analysis codes. The development employs a 

three-pronged approach: 

Local-global approach for developing robust spot weld crash simulation framework.
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•	 a spot weld element formulation and 

associated constitutive models for 

robustness in computer aided engineering simulation, with the complexity to 

incorporate weld geometry and microstructure effects;

•	 a physics based integrated electricalthermal-mechanical-metallurgical spot 

weld process model to generate the weld 

geometry, microstructure, and residual 

stress results needed by the spot weld 

element; and

•	 a companion weld characterization and 

impact test database for development 

and validation of the new spot weld 

modeling approach. 

In 2011 the team completed comprehensive 

testing and characterization of resistance 

spot welds, generating a data set of static 

strength and failure modes under 4 loading conditions covering 17 groups of AHSS 

grades, coatings, and thicknesses. For each 

group, welds were produced with three different weld nugget sizes. The welded samples were tested under lap-shear, crosstension, and coach-peel conditions and 

a specially designed in-plane torsion 

condition. The testing matrix covered 

more than 220 unique combinations of 

materials, welding, and mechanical testing conditions. Multiple duplicates of 

welds were produced for each combination for microstructure characterization, 

microhardness mapping, and miniature 

mechanical property testing to be carried out in 2012. A project web page has 

been created to distribute FEM models, 

formulations, and results at thyme.ornl.

gov/SPW.

The integrated spot welding process and 

performance model has been successfully developed with all essential features to handle various materials, joint 

geometries, and welding process conditions typically encountered in resistance 

spot welding of AHSS auto body components and has been shown to be stable 

and robust. The model will be further 

validated in 2012 using the experimental data set generated in 2011. 
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Highlights

Propulsion System Materials

Ultrahigh-Resolution Electron 

Microscopy for Catalyst 

Characterization

Oak Ridge National Laboratory (ORNL) is 

using the ultrahigh-resolution aberrationcorrected electron microscope at the 

High Temperature Materials Laboratory 

to advance fundamental understanding of 

how catalysts behave at the atomic level. 

This research has shown, through subÅngström resolution imaging coupled with 

surface analytical techniques, that single 

atoms can catalyze reactions and be stable for long periods. The first demonstration of the efficacy of single-atom catalysis offers the promise of after-treatment 

systems that lower vehicle emissions at a 

reduced cost (due to lower catalyst loading) with a higher performance level than 

conventional catalysis. ORNL is partnering 

with universities, industry, and another 

national laboratory to use these capabilities for studies of catalytic materials and 

reactions leading to improved automotive 

catalysts.

ORNL contributions to this project are 

furthering catalyst studies through the 

development of innovative capabilities 

for imaging catalytic materials in situ at 

elevated temperatures and pressures up 

to a full atmosphere, and under reactive 

gas conditions. This allows atomic-level 

imaging in ORNL’s aberration-corrected 

electron microscope that elucidates 

mechanisms of catalyst behavior. The 

team is employing a third-generation design environmental cell, or “Gen 3 E-cell,” 

holder that incorporates a unique heater 

manufactured by an industry partner. The 

Gen 3 E-cell is used to study new nitrogen 

oxide reduction materials called “intelligent catalysts,” which are composed of 

The first example of a “single-atom” catalyst; the three 

bright spots are platinum atoms on the surface of an iron 

oxide support material.
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precious metal species such as platinum 

and rhodium in perovskite. Through in situ 

oxidation and reduction cycling experiments, 

researchers are obtaining a fundamental 

understanding of the mechanisms and 

kinetics of the cyclic dissolution and subsequent reformation of catalytic nanoparticles 

on support surfaces during the redox cycles. 

Remarkably, studies of a rhodium-perovskite 

catalyst in the Gen 3 E-cell showed atomic 

•	 Qiao, B., et al. August 2011. “Single-atom Catalysis of CO Oxidation using Pt1/FeOx.” 

Nature Chemistry 3(8):634–641.

Results of a reduction experiment on a platinum-perovskite material using 

ORNL’s specialized in situ heating technology. Bright spots are platinum 

nanoparticles. Image on the left was taken before the reduction treatment; 

image on the right is after a reduction treatment for 1 minute in a 50 Torr 

reducing atmosphere at a nominal temperature of 800°C.

structure at the Ångström level can be 

imaged at elevated temperatures in gas 

pressures up to a full atmosphere in the 

cell with essentially no loss of signal. 

ORNL’s in situ heating technology is the 

only method in the field that presently 

allows such precision control of a reaction process, in time, temperature, and 

pressure. 

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Highlights

ORNL’s CF8C-Plus Stainless Steel 

Targeted for High Temperature 

Turbocharger Applications

ORNL is partnering with Honeywell, a major international turbocharger manufacturer, to develop new materials for advanced 

turbocharger components. 

Turbochargers are key components in 

advanced fuel-efficient engines. They are 

used to increase power output and efficiency by increasing the ratio of mass 

to air to the cylinders, thereby enabling 

higher fueling rates, more power, and 

reductions in engine size without increasing regulated emissions. Recent advances 

in turbocharging have yielded higher intake 

pressures resulting in efficiency improvements up to 20% in gasoline engines and 

up to 40% in diesel engines. Additional 

efficiency gains are expected with further 

increases in pressure; however, these 

increases in pressure and the accompanying increases in temperature are stressing 

traditional turbocharger materials and 

driving the search for newer, more robust 

materials and designs to withstand these 

more extreme conditions.

Honeywell and ORNL initially assessed 

the effects of higher exhaust temperatures on turbocharger materials and 

components and identified turbocharger 

housings as priority components for 

consideration under this project. Several years ago ORNL developed a special 

cast austenitic stainless steel, CF8CPlus, with higher temperature capabilities and greater durability. CF8C-Plus is 

in commercial use in advanced diesel 

engine exhaust component applications. 

Alloying additions of manganese and 

nitrogen give this alloy excellent castability and improved high-temperature 

strength based on nanoscale dispersions 

of carbide and nitride precipitates. The 

CF8C-Plus steel also has good fatigue 

Comparison of creep rupture (top) and yield strength (bottom) for CF8C-Plus and HK30Nb 

cast austenitic stainless steels.
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resistance and aging resistance. Honeywell and ORNL have targeted this material 

for more in-depth study as a potential 

upgrade material for the turbocharger 

housing application.

Turbocharger housings for diesel and gasoline engines are typically made of cast 

irons, which have limitations in terms of 

temperature capability. To date, comparisons of CF8C-Plus steel to various cast 

irons have established CF8C-Plus’ superiority. The CF8C-Plus steel alloy has also 

demonstrated much better creep rupture 

resistance and greater tensile strength 

in the temperature range from 700°C to 

900°C compared to other more expensive 

commercial stainless alloys such as 

HK30Nb. In addition, use of CF8C-Plus 

in turbocharger housings would reduce 

turbocharger weight relative to cast iron 

further contributing to fuel efficiency 

and life cycle energy savings. 

CF8C-Plus has not yet been commercialized for Honeywell turbochargers, but 

the material is showing promise as a 

turbo housing material. Honeywell and 

ORNL are continuing to partner on turbocharger housing materials under this 

project and are expanding the search to 

alternate high-temperature materials for 

other turbocharger components.

•	 Maziasz, Philip J., and Pat Pattabiraman. 2011. “CRADA NFE-08-01671—Materials 

for Advanced Turbocharger Design.” Presented at the 2011 DOE Hydrogen Program 

and Vehicle Technologies Program Annual Merit Review and Peer Evaluation Meeting, 

Washington, D.C., May 9–13.

•	 Maziasz, P. J., A. Shyam, and N. D. Evans. 2010. Cast CF8C-Plus Stainless Steel for Turbocharger Applications. ORNL/TM-2010/86, Oak Ridge National Laboratory, Oak Ridge, 

Tennessee. 

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Highlights

Durability of Diesel 

Particulate Filters

ORNL’s modeling capabilities, which have 

proven successful in elucidating materials 

science phenomena that impact industry, 

were recently put to use in modeling diesel 

particulate filter (DPF) service life.

DPFs reduce emissions of particulate matter (PM), or soot; hydrocarbons; and carbon 

monoxide by 60–90% thus enabling advanced diesel engines to meet the stringent 

regulation of PM that went into effect in 

2007. DPF service life predictions are therefore of great importance to the automotive 

and truck industries.

Ceramic honeycomb devices are typically used as DPFs. They collect PM in the 

exhaust stream of the engine. Because 

ceramics are highly heat resistant, they 

can withstand the high temperature 

of the exhaust (approximately 500°C) 

needed to break down or oxidize PM 

inside the filter. This process is called 

filter regeneration and is triggered when 

a specified level of PM accumulates in 

the DPF. 

The top image shows an axisymmetric DPF with a predefined thermal profile. 

As the exhaust flows left to right, the profile is hottest in the center. The middle 

images show the corresponding thermal strain for two DPFs, one (modulus 2, on 

the right) with an elastic modulus twice that of the other (modulus 1, on the left). 

The bottom graphs show a lower elastic modulus results in a significantly higher 

predicted number of regeneration cycles before DPF failure.
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DPF service life predictions are based 

on a combination of experimentally 

determined strength data, stress analyses (for example, that produced using 

finite-element analysis), and selection 

of appropriate failure criteria. Typically, 

experimental material data are collected 

and then used in predictive models to 

estimate filter lifetimes in terms of regeneration cycles.

Recent end-user observations of DPF 

performance indicate service lifetime 

expectations longer than ever before—

positive news for manufacturers and 

industry. To explore the cause of the low 

failure rate, General Motors and ORNL 

researchers found the apparent elastic 

modulus of the filter ceramics to be 

almost an order of magnitude lower 

than industry-accepted values when 

using more appropriate means for its 

measurement. According to ORNL’s Andrew Wereszczak, “The measurements 

indicate that while the filter is under 

thermally induced strain, such as that 

during regeneration, the actual internal 

stresses are much lower and mechanical 

reliability is much higher than manufacturer models have predicted in the 

past because of that lower actual elastic 

modulus.” 

Further understanding of the relationships between microstructural material 

properties and their performance in 

DPFs will lead to improved materials and designs that will enhance the 

effectiveness and efficiency of diesel 

engines in general. Cleaner diesel operation will help increase public acceptance of the more fuel-efficient diesel 

with a resulting concomitant reduction 

in petroleum use.

•	 Lance, M. J., et al. January 2012. “Agreement 20091 - Electrically-Assisted Diesel Particulate Filter Regeneration.” In 2011 Progress Report for Propulsion Materials, 253–271. 

ORNL/TM-2011/34212, U.S. Department of Energy, Washington, D.C.

Experimental set up for measuring elastic modulus. The 2 × 

2 cell specimen is loaded in 

3-point-bending apparatus, and 

its deflection response is measured as a function of frequency 

while oscillation amplitude is 

held constant.

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Highlights

Power Electronics & Electric Machines

Inverter Using Current 

Source Topology

ORNL researchers have designed, fabricated, 

and tested a 10 kW Z-source current source 

inverter (ZCSI) prototype that promises to 

overcome the drawbacks of traditional voltage source inverters (VSIs) and significantly 

advance electric vehicle technology toward 

DOE and U.S. DRIVE goals for size, weight, 

and cost.

VSIs using film capacitors are universally employed in hybrid, plug-in, and battery electric 

vehicles. The technology, although mature 

and well established, has many drawbacks. 

For example, it requires an expensive and 

bulky direct current (dc) bus capacitor, and 

it produces high electromagnetic interference, detrimental voltage stresses on the 

motor insulation, high frequency losses, and 

harmful bearing leakage currents. Long-term 

reliability issues also exist due to possible dc 

bus shoot-through conditions. Additionally, to 

increase the output voltage of a VSI a larger 

battery pack must be used or a dc-dc 

converter must be incorporated into the 

system. Both of these options result in 

unwanted cost, weight, and volume.

To overcome the limitations of VSIs, 

ORNL researchers are using new reverseblocking semiconductor devices in a new 

topology called ZCSI, which integrates 

the boost converter, inverter, and battery charger functions; improves fault 

tolerance; and substantially reduces 

capacitor requirements. The new design 

is capable of functioning as a universal 

charger for plug-in hybrid electric vehicles, allowing charging of low-voltage 

and high-voltage batteries from single- 

(120 V/240 V) or three-phase supplies. 

In testing, the prototype has demonstrated the following advances over the 

conventional VSI technology.

Photo of the 10 kW ZCSI prototype.
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•	 Capacitance reduction to 200 μF (2,000 

μF for VSI)

•	 Output voltage boost capability ranging 

from 0 to 3 times the battery voltage 

(0–0.99 for VSI)

•	 Output voltage total harmonic distortion 

factors of 6%–12% (70%–200% for VSI)

•	 Power density and specific power of 4.9 

kW/kg, 16.6 kW/L (4.3 kW/kg, 7.1 kW/L 

for Camry VSI)

•	 More than 97% efficient even with a relatively low source voltage of 250 V

The prototype 10 kW ZCSI was designed using first generation reverse 

blocking semiconductor device technology. The project team plans to design, 

fabricate, and test a 55 kW ZCSI prototype when new reverse blocking switching devices become available.

•	 Tang, L., and G. J. Su. 2011. “A Novel Current Angle Control Scheme in a Current 

Source Inverter Fed Surface-Mounted Permanent Magnet Synchronous Motor Drive.” 

Energy Conversion Congress and Exposition (ECCE), 2011 IEEE, 2358–2364.

•	 Su, G. J. “Power Conversion Apparatus and Method.” U.S. Patent 8,110,948, filed 

March 6, 2009, and issued February 7, 2012.

Efficiency chart for the ZCSI prototype, 

indicating a maximum efficiency of 97.6%.

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Highlights

Planar Bond Power 

Electronics Module

ORNL is developing advanced automotive power electronics packaging technologies to help achieve DOE and U.S. 

DRIVE targets for power density and cost. 

This involves multidisciplinary capabilities including material development and 

characterization; thermal, electrical, and 

thermomechanical expertise; and reliability, process, and manufacturing considerations.

A prototype 200 A/1,200 V phase leg 

power module, called “Planar_Bond_All,” 

has been fabricated in-house at the ORNL 

Power Electronics Packaging Laboratory. 

The module features double-sided planar 

electrical interconnections and integrated 

mini-coolers. The versatility of the module 

allows it to be air cooled on pin fins or 

cooled with liquid mini-coolers on one or 

both sides for increased heat rejection. 

The module’s planar interconnections 

allow large bonding contact areas. The 

package is constructed so that the switch 

die are oriented in face up/face down 

insulated gate bipolar transistor/diode die 

pairs. This packaging arrangement leads 

to significantly reduced parasitic parameters—80% less than the state-of-the-art 

module in the 2010 Toyota Prius; and the 

double-sided cooling capability reduces 

the thermal resistivity of the whole module assembly to 0.33°C∙cm2/W—30% less 

than the 2010 Prius module.

Planar_Bond_All photo showing double-sided 

planar interconnections.

Planar_Bond_All photo showing double-sided 

planar interconnections and integrated minicoolers.
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But what makes Planar_Bond_All truly a 

paradigm shift in power module packaging 

is the processing technology used to create the module. It reduces the conventional 

multiple hybrid packaging processes to 

just two steps. In the first step all the components are assembled into a fixture for 

processing. The second step involves heating of the assembly to form the bonds and 

create the final package. The simplicity of 

the process will reduce costs and improve 

the manufacturability of the module.

•	 Liang, Zhenxian, Fred Wang, Puqi Ning, and Laura Marlino. Power Module Packaging 

with Double Sided Planar Interconnection and Heat Exchangers. U.S. Patent application serial number 61/509,312.

•	 Liang, Zhenxian, Puqi Ning, Fred Wang, and Laura Marlino. 2011. “Power Module 

Packaging with Double Sided Planar Interconnection and Heat Exchanger.” Presented 

at ORNL Power Electronics Symposium, Oak Ridge, Tennessee, July 22. 

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Highlights

Novel Switched Reluctance 

Motor Design

Switched reluctance (SR) motors are of 

interest to automotive manufacturers 

because they do not use rare earth permanent magnets, which are subject to 

unpredictable availability and cost; and 

because their simplicity offers many cost 

and manufacturing benefits. Two primary 

drawbacks of the SR motor are the level 

of torque ripple and the acoustic noise 

inherently associated with its stator and 

rotor geometry. ORNL has developed a 

novel SR motor with isolated multiple flux 

paths (IMFPs) to facilitate better control 

over torque ripple and acoustic noise with 

a secondary goal of improving power density and specific power. An SR motor stator and/or rotor with IMFP segments has 

the potential to locate teeth within closer 

proximity of each other while maintaining 

magnetic saliency, which is the fundamental manner in which torque is produced in 

SR motors. 

The final SR motor design consists of 

6 segmented stator pieces forming 12 

stator teeth and a conventional SR rotor 

with 10 teeth. The use of segmented 

stator pieces opens up design opportunities that can lead to increased power 

density and/or reduced torque ripple and 

acoustic noise. One primary advantage is 

the capability to have yoke-wound stator 

coils, as shown in the figure. While using 

this winding technique at first seems 

insignificant, a closer look reveals the following benefits.

•	 Copper windings are located on the 

outer perimeter of the motor and are 

well positioned for interfacing with 

a heat exchanger for improved heat 

transfer. This will increase continuous 

operation capability.

Partially assembled prototype showing yokewound stator coils.
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•	 Broader teeth allow the torque production from each phase to overlap the 

torque production between phases. 

Increased overlap of torque production between phases can reduce torque 

ripple, and because the broader teeth 

are more substantial, they are less likely 

to vibrate and create acoustic noise.

•	 Slots contain one coil instead of two, 

thereby eliminating issues with interference between coils. 

•	 Stator pieces can be wound before installation, facilitating manufacturability.

•	 Voids between stator pieces can be 

filled with noise damping material.

Because of the unconventional nature 

of the IMFP SR motor, ORNL developed 

custom design and simulation tools 

that were used in optimization studies 

and in formulating control algorithms. 

In simulations the novel SR motor 

achieved 52.4 kW (125 Nm at 4,000 

rpm) with 5% torque ripple and 93% efficiency. A prototype has been fabricated and is being testing in the dynamometer facility at ORNL’s Power Electronics 

and Electric Machinery Research Center.

•	 Burress, T., and C. Ayers. Isolated Multiple Flux Path Reluctance Motors with YokeWound Coils and Wedge Supports. U.S. Patent application serial number 61/509,213.

Simulated peak torque and power versus speed for various 

torque ripple levels.

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Highlights

Vehicle & Systems Simulation & Integration

Wireless Plug-In Electric Vehicle 

Charging Development and 

Demonstration

Wireless power transfer (WPT) permits a 

plug-in electric vehicle (PEV) to recharge 

its battery without plugging in. It is seen 

as a key enabling technology supporting 

widespread acceptance of PEVs. ORNL has 

developed and demonstrated, in laboratory-scale experiments, a new WPT concept 

that has achieved efficiencies in the low 

90% range. Current WPT systems operating at high power typically have efficiencies 

in the high 70% to high 80% range. 

ORNL’s objectives were twofold: (1) to 

develop full analytical, computational, and 

experimental understanding of the physics of wireless power charging so that 

implementation designs will meet industry 

requirements for efficiency, safety, cost, 

and vehicle packaging criteria; and (2) to 

develop WPT stationary charging sufficiently for integration into a demonstration vehicle.

ORNL leveraged its “evanescent wave” experimental hardware, a Laboratory Directed Research and Development technology, 

to show the flexibility of WPT in accommodating arbitrary receiver-side voltage 

levels (120 Vdc, 240 Vdc, and moving to 

270 Vdc). This will be required for WPT in 

future vehicle applications because there 

is not a standardized PEV battery pack 

voltage level. 

Work to date has established a firm foundation in the fundamentals of WPT operaWPT Laboratory apparatus in copper tube coil configuration.
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tion from both analytical and experimental 

investigations. Primary activity has focused 

on coupling coil electromagnetic performance, magnetic field strength, emissions 

levels, and closest approach boundary for 

compliance with international standards. 

Coupling coils constructed of copper tube 

and flat designs were compared in experimental tests; both exhibited comparable 

efficiency with the ac resistance of each 

being within 2%. A more fundamental finding, based on analytical work, was that the 

insulated gate bipolar transistors (current 

technology) are limiting the operation to 

suboptimal conditions. Recent announcements indicate that new insulated gate 

bipolar transistors capable of high current 

switching up to 200 kHz may be available in 

the near future; if not, the team will work 

with ORNL’s Power Electronics Packaging 

Laboratory to fabricate high-frequency 

power modules. 

Future work includes optimizing the 

coupling coil designs and fabricating 

and testing suitably packaged transmit 

(primary) and receiver (secondary) pads 

based on those optimized designs. The 

effects of concrete, asphalt, plastic and 

plywood on coupling coil transfer efficiency and system tuning have been 

evaluated. The full WPT system will be 

bench validated and then integrated into 

a vehicle for demonstration on the ORNL 

Hardin Valley campus.

•	 Scudiere, M., J. McKeever, and J. M. Miller. 2011. “Wireless Power Transfer for Electric Vehicles.” Presented at SAE World Congress, Detroit, Michigan, April 12–14. 

Paper number 2011-01-0354. doi:10.4271/2011-01-0354

•	 Miller, J. M. “Coupling Coil ac Resistance Minimization Using Graphene Coatings.” 

U.S. Patent Application 61/510,206, filed July 21, 2011.

•	 Miller, J. M. “Regulation Control and Energy Management Strategy for Wireless 

Power Transfer.” U.S. Patent Application 61/510,210, filed July 21, 2011.

•	 Miller, J. M., and P. T. Jones. “WPT EVSE Installation and Validation Tool.” U.S. Patent Application 61/510,231, filed July 21, 2011.

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Highlights

Plug-In Hybrid Electric Vehicle 

Engine Control and Energy 

Management Strategy

Plug-in hybrid electric vehicles (PHEVs) 

have the potential to reduce petroleum 

consumption considerably; however, this is 

at the expense of increased tailpipe emissions due to multiple cold start events 

for the gasoline engine. PHEVs operate 

predominantly as electric vehicles (EVs) 

with intermittent assist from the engine 

during high power demands (for example, 

accelerating from urban traffic to highway 

driving). As a consequence, the engine 

experiences multiple cold start events 

that have a significant impact on tailpipe 

emissions due to degraded catalyst performance and starting the engine under 

less than ideal conditions. ORNL is working with industry partners, universities, 

and other national laboratories to address 

the cold start challenge in PHEVs through 

novel engine control strategies targeted 

at rapid engine and catalyst warming to 

mitigate tailpipe emissions. The project 

team also aims to validate and optimize 

hybrid supervisory control techniques 

developed during other research projects 

by integrating them into the vehicle level 

control system and complementing them 

with modified engine control strategies 

to further reduce emissions during both 

cold start and engine restarts. 

A modified production engine controller from Robert Bosch LLC is being used 

on a GM Ecotec LNF engine; the engine 

and controller were commissioned on 

an engine test cell in the ORNL Fuels, 

Engines and Emissions Research Center. 

The open-calibration controller allows 

modification of cold start strategies to 

assess the effects of different operatEngine-in-the-loop test platform.

National Instruments HIL based on PXI 

Hardware VeriStand Software

Engine Dyno

Speed/torque

Dyno Controller

Speed Setpoint

Speed and torque feedback

Controller

Motor 

Inverter

Engine 

torque 

setpoint
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ing modes on the engine and emissions 

mitigation systems. The project team is 

using the Autonomie simulation program 

(developed by Argonne National Laboratory) in a unique “engine-in-the-loop” test 

system that allows interfacing the Autonomie PHEV model with the real engine on a 

dynamometer test stand.

The control system has been tested to 

demonstrate the impact of various engine 

control parameters on cold start emissions, and the test setup was used to 

demonstrate the potential for further 

emissions reduction and faster catalyst 

warm-up by modifying engine cold start 

calibration. During 2012, the project 

team will proceed with combined optimization of both engine- and vehiclelevel strategies to achieve lower cold 

start emissions in the hybrid powertrain 

configuration.

Emissions improvements and fuel penalty associated with vehicle supervisory strategies 

that prewarm the engine and filter out transient conditions while the engine is cold.

•	 Chambon, Paul H. 2011. “PHEV Engine Control and Energy Management Strategy.” 

Presented at the 2011 U.S. DOE Hydrogen Program and Vehicle Technologies Program 

Annual Merit Review and Peer Evaluation Meeting, Washington, D.C., May 9–23.

Publications
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Highlights

Advanced Modeling and Analysis 

for Hybrid Vehicle Systems

Accurate predictions of the fuel efficiency 

and environmental impact of advanced 

vehicle propulsion and emissions control 

technologies are vital for informed decision making about DOE programmatic 

priorities and optimal use of DOE resources. To this end, DOE tasked ORNL 

with providing component data and 

models that enable simulations of hybrid 

vehicle systems with advanced engines 

and emissions controls. ORNL’s progress 

includes numerous experimental measurements of emissions and fuel efficiency for advanced diesel and lean-burn 

gasoline engines and their associated 

emissions control components. These 

data have been transformed into maps 

and low-order transient models that support vehicle performance simulations. 

In 2011, the ORNL team collaborated 

with Argonne and Pacific Northwest 

National Laboratories to develop integrated transient engine and aftertreatment component models suitable for 

implementation in PSAT and Autonomie. 

These models were then used to generate 

improved simulations of emissions and 

fuel economy for hybrid electric vehicles 

(HEVs) and plug-in hybrid electric vehicles 

(PHEVs) powered by both stoichiometric 

and lean-burn engines. Major accomplishments included the following.

•	 Constructed and made preliminary 

parameter estimates for a computational model of a passive adsorber for 

exhaust hydrocarbons and nitrogen 

oxides (NOx), and applied the adsorber 

model to simulations of HEVs and 

PHEVs with stoichiometric gasoline 

engines and three-way catalyst (TWC) 

emissions controls. 

•	 Enhanced a previously developed transient engine model to explicitly include 

thermal interactions among the engine 

block, coolant, and radiator.

•	 Evaluated the potential benefits of advanced combustion and aftertreatment 

technologies on fuel efficiency and 

emissions control of diesel-powered 

hybrid vehicles equipped with appropriate aftertreatment trains.

Comparison between predicted and measured coolant temperature and exhaust temperature for the PHEV Prius with a cold start at -7°C.
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•	 Successfully translated ORNL’s low-order TWC, diesel oxidation catalyst, lean 

NOx trap, catalyzed diesel particulate 

filter, and transient engine models from 

PSAT into Autonomie.

•	 Developed an independent graphical input simulation tool for TWC for research 

use.

Modeling and research results were made 

available to the public in a series of articles 

including one comparing the simulated 

emissions and fuel efficiencies of diesel 

and gasoline hybrid electric vehicles and 

another on a phenomenological computer model for rapidly estimating NOx

and particulate emissions from advanced diesel engines operating in the 

premixed-charge compression ignition 

mode.

The tools developed to date will be 

transferred to system simulation tasks 

associated with a Cooperative Research 

and Development Agreement between 

ORNL and Meritor, and simulations of 

cold-start effects and control system 

optimization in collaboration with other 

national laboratories.

•	 Gao, Z., V. K. Chakravarthy, and C. S. Daw. 2011. “Comparisons of Simulated Emissions and Fuel Efficiency of Diesel and Gasoline Hybrid Electric Vehicles.” Proceedings of the Institution of Mechanical Engineers, Part D: Journal of Automobile Engineering

225(7):944–959.

•	 Gao, Z., R. M. Wagner, C. S. Sluder, C. S. Daw, and J. B. Green Jr. 2011. “Using a Phenomenological Computer Model to Investigate Advanced Combustion Trajectories in a 

CIDI Engine.” Fuel 90(5):1907–1918.

Engine speed-load map illustrating opportunities for premixed-charge compression 

ignition use during an urban driving duty cycle for (a) a conventional (nonhybrid) 

passenger vehicle and (b) an equivalent size HEV. Pink crosses correspond to engine 

operating points. Solid colors correspond to engine-out NOX levels.

Publications
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118

Highlights

Medium Truck Duty 

Cycle Project

Bucket truck (left) and flat-bed recovery vehicle (right) representative of vehicles used in 

the MTDC project.

ORNL’s Medium Truck Duty Cycle (MTDC) 

project—involving data collection, analysis, 

and reporting for Class 6 and 7 trucks—is 

producing a database of duty cycle and 

vehicle performance data available nowhere else in the world. The MTDC project 

complements a prior, similar effort that 

focused on Class 8 trucks. Together, the 

data represent an unprecedented 800 

million records of heavy- and medium-size 

vehicle information in one database. The 

information is supporting DOE’s modeling 

efforts and technology investment decision-making, as well as specialized energy 

efficiency studies. The MTDC project collected 73 channels of data related to fuel 

use, engine parameters, speed, direction 

of travel, time of day, geographic position, 

road grade, weather conditions, and road 

conditions. Transit buses, Class 7 combination tractor-trailers, utility trucks, and 

towing and recovery trucks were included 

in the study. Data collection has been completed and analysis is ongoing. Overall, the 

MTDC project has produced about 245 

GB of data. In the future, a public website 

will be developed where researchers can 

access analyzed and summarized data. 

The project team has developed a set of 

software tools to quickly interrogate the 

data available on a candidate vehicle, 

wirelessly transfer data from the vehicles, 

validate the data, and select data segments for analysis. In addition, a Duty 

Cycle Generation Tool is being developed 

that will allow the research community to 

generate customized, real world–based 

duty cycles; for example, a duty cycle for 

a metropolitan area during peak travel 

times, or one for a rural area with steep 

grades. The Duty Cycle Generation Tool 

can also be used to generate synthetic 

duty cycles statistically representative of 

original duty cycles, but much smaller, 

making analysis and modeling faster while 

giving the same or similar results. 
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•	 Franzese, O., M. B. Lascurain, and G. Capps. 2011. Medium Truck Duty Cycle Data from 

Real-World Driving Environments: Project Interim Report. ORNL/TM-2010/255, Oak 

Ridge National Laboratory, Oak Ridge, Tennessee.

•	 Franzese, O., and D. Davidson. 2011. Effect of Weight and Roadway Grade on the Fuel 

Economy of Class-8 Freight Trucks. ORNL-TM-2011/471, Oak Ridge National Laboratory, Oak Ridge, Tennessee.

Duty Cycle Generation Tool showing comparison of original (top) 

and synthetic (bottom) duty cycles

The MTDC and heavy truck duty cycle 

projects are meeting diverse research 

needs. Argonne National Laboratory 

has used the database in support of its 

vehicle modeling using the Powertrain 

System Analysis Toolkit and Autonomie 

tools. The Department of Transportation’s Federal Motor Carrier Safety 

Administration has joined with the 

project to collect brake and tire performance data. Heavy truck data were used in 

an ORNL study of the effects of weight and 

grade on fuel economy for the Department 

of Transportation’s Federal Highway Administration. Additionally, methods for synthetically generating emissions data are being 

discussed and a potential partnership with 

the Environmental Protection Agency is being explored. 

Publications