bluuebunny/crossref_metadata_2025_split huggingface dataset:
On the Effect of the Flow Field Plate’s Geometry on the Polymer Electrolyte Membrane Water Electrolysis Cell’s Performance
Authors: Al Shakhshir Saher , Kær Søren Knudsen 
Published: February 2020

The key for successful commercialization of fuel cell products, such as Fuel Cell Vehicle, Hydrogen-Powered busses, and Hydrogen-Powered Passenger Train is compact, safe, reliable, rapid response, high hydrogen purity, dynamic operation, and high pressure system for hydrogen storage technology. These quality characteristics of hydrogen storage technology can be met by polymer electrolyte membrane water electrolysis (PEMWE) technology. Also the high compatibility of PEMWE technology with intermittent renewable energy sources leads to quicker commercialization of fuel cell products.
Flow field plates (FFPs) along with the current collectors represent 48% of the stack cost. Also, FFPs are responsible for distributing reactant water and removing the pure oxygen with unreacted water from the anode side and hydrogen with crossed over water from the cathode side. Thus, FFPs must be probably designed to distribute reactant water evenly resulting in more uniform electrochemical reaction over all the active area of the PEMWE cell. Uniform electrochemical reaction leads to uniform current and temperature distribution. Therefore, the cell performance might be developed and degradation rate might be reduced.
The present work presents the effect of the most common FFPs geometries; single serpentine, interdigitated, and parallel geometry on the polarization resistances using electrochemical impedance spectroscopy (EIS) measurements and on the whole cell performance using the IV curve measurements are experimentally demonstrated. Each anode FFP’s geometry is tested with three different cathode’s FEPs geometries. Thus, the effect 9 geometries combined between the anode and the cathode of a 50 cm2 PEMWE cell are presented in this work. All the geometries have the same inlet and outlet manifold design. Thus, the pressure drop between the inlet and the outlet of each FFP’s geometry is also presented in this work.
Challenging of Reducing Electrolysis Voltage by Superimposing Boiling on PEMWE–A Thermodynamic Coupling–
Authors: Ito Kohei , Terabaru Kenji , Li Hua , Inada Akiko , Nakajima Hironori 
Published: February 2020

We challenge to reduce electrolysis voltage by thermodynamic coupling. When PEMWE reaches 100°C under atmospheric pressure, boiling progresses spontaneously and contributes to entropy generation. In principle, the entropy generation accelerates water electrolysis reaction through the thermodynamic coupling, resulting in reducing the electrolysis voltage of PEMWE.
In this study, we experimentally clarify whether electrolysis voltage drop at boiling temperature. The electrolysis voltage of a PEMFC is continuously measured while raising operation temperature from 80°C to 120°C under constant operation pressure (0.1 MPa) and electrolysis current (0.002 A/cm2). If the electrolysis voltage drops at boiling temperature, this matter becomes an evidence for the thermodynamic coupling between boiling and electrolysis. PEMWE used in this study embeds a CCM made with spray and hot-press method. Polymer electrolyte membrane (PEM) is Aquivion membrane. Catalyst layer formed on the membrane consists of IrO2 (1.5mg/cm2) for anode and PT/C (0.5mg/cm2) for cathode. The area of catalyst layer is 4 cm2.
Figure shows the electrolysis voltage and HFR (high frequency resistance, 1 kHz) to the change of temperature. The HFR approximately corresponds to proton resistance through PEM. The electrolysis voltage begins to abruptly decrease just over 100°C, and turns to increase at 105°C, showing a valley on the temperature-voltage characteristics. Each slope on the characteristic (dV/dT) near 80°C and 120°C closes to temperature dependence of water-electrolysis Gibbs free energy change (ΔG(T)) in the case of liquid and gas, respectively.
The electrolysis voltage drop appeared is analyzed based on overvoltage component. HFR began to increase just over boiling point, because water in cell evaporated, PEM dried up and the proton resistance rose. However, ohmic overvoltage change attributed to the rise of proton resistance is neglectable to the electrolysis voltage change. Concentration overvoltage also can not explain the electrolysis voltage drop, because the current is controlled to be small as 0.002 A/cm2. Thus, the voltage drop appeared near boiling point attributes to the effect of boiling on activation overvoltage and/or Nernst voltage.
To summarize, the electrolysis voltage in PEMWE shows the abrupt drop near 100°C under atmospheric pressure and and small electrolysis current (0.002 A/cm2) when temperature successively rises from 80°C to 120°C. Boiling imposed in the cell is thought to impact the electrolysis voltage drop through the thermodynamic coupling. The boiling, specifically, is considered to impact on activation overvoltage and/or Nernst voltage, leading to the voltage drop.

Figure 1
Electrochemical Synthesis of Ammonia Using Proton and Hydroxide Exchange Membrane Cells
Authors: Nash Jared , Wang Junhua , Anibal Jacob , Yan Yushan , Xu Bingjun 
Published: February 2020

With the development of the Haber process and the subsequent work done by Bosch, ammonia production become an industrially and economically viable way to fix nitrogen. Ammonia used as a fertilizer has helped increase the global food production and estimates put it at about 40% of the global population’s food needs the ammonia fertilizer from the Haber process[1]. However, the Haber-Bosch process is an energy intensive process requiring high pressure (15-30 MPa) and relatively high temperature (430 °C – 480 °C) and is highly centralized with only about 13 companies producing at about 29 plants[2, 3]. Renewable energy resources offer a possible alternative way to fix nitrogen at low temperature and lower pressure to produce ammonia in a decentralized way. High temperature solid proton conductors have been used to produce ammonia selectively, but the high temperature can degrade the ammonia[5]. Low temperature polymer electrolyte membranes can be used which might reduce the overall energy input. Proton exchange membrane (PEM) suffers from conductivity loss due to the ammonia converting to ammonium[6], which reduces the cation conductivity. The other issue is the competing hydrogen evolution reaction (HER) which is especially fast in the acidic environment[7]. By moving to an alkaline environment, ammonia will not affect the conductivity because hydroxide exchange membranes (HEMs) use anions as the charge carriers. HEMs also allow the use of non-precious metal catalysts which could reduce the overall cost of these electrochemical devices. In this presentation, we will discuss the activity of a variety of catalyst, PGMs, metal nitrides, and non-precious metals in both HEM and PEM electrolyzers for their ammonia production. We utilized the hydrogen oxidation reaction (HOR) as the counter electrode which can also be utilized as a reference. This study allows for the direct comparison of PEM and HEM for electrochemical nitrogen reduction.
References:
1. Erisman, J.W., et al., Nature Geosci, 1(10): p. 636.(2008).
2. Mineral Commodity Summaries 2015, U.S.G. Survey, 2015: Reston, Virginia. p. 196.
3. Marnellos, G. and M. Stoukides, Science, 282(5386): p. 98.(1998).
4. Kordali, V., G. Kyriacou, and C. Lambrou, Chem. Commun., (17): p. 1673.(2000).
5. Amar, I.A., et al., J Solid State Electrochem, 15(9): p. 1845.(2011).
6. Lan, R. and S. Tao, RSC Advances, 3(39): p. 18016.(2013).
7. Sheng, W., H.A. Gasteiger, and Y. Shao-Horn, J. Electrochem. Soc., 157(11): p. B1529.(2010).
(Invited Plenary) From Moon Shot to the Battlefield and Under the Sea
Authors: Freese Charles 
Published: February 2020

Accelerating Fuel Cell Transition to Commercial Reality
For more than 100 years, the automotive industry fostered prolific technical innovation and business change. Today, the industry is transforming itself in a concentrated effort to create electrified vehicle architectures from both battery and fuel cell technologies. General Motors began its fuel cell journey more than 50 years ago when the Electrovan became world’s first hydrogen-powered fuel cell vehicle, a feat made possible by the first technology transfer from the Apollo Space Program. Although Electrovan was an important milestone, it highlighted technical challenges that had to be solved before fuel cells could become commercially viable. One by one, these barriers were broken over succeeding decades, and as the 20thCentury closed, GM prepared for the first large-scale fuel cell deployment. Project Driveway placed 119 fuel cell vehicles in customer garages and driveways, with more than 5,000 motorists amassing 3.2 million miles of real-world driving. These Generation 0 systems continue to gather useful data though U.S. military collaborations with the U.S. Army and U.S. Navy. Meanwhile, GM is partnering with Honda in a joint venture to mass produce next-generation fuel cell systems. GM’s HydroTec fuel cell technology is undergoing evaluations, on land, under water, and in the air. Incredible progress has been made in reducing the mass and cost, but additional challenges remain, specifically in creating a scalable public fueling infrastructure in the United States, Japan, Germany and Korea.
(Invited Plenary) Latest Research and Development of PEM Water Electrolysis Technology in South Korea
Authors: Moon Sangbong , Moon Changhwan , Jung Hyeyoung , Choi Yunki , Han Changhyun 
Published: February 2020

Reduction of CO2 emission has been an issue around the globe, and most countries are considering renewable energy such as solar and wind power to reduce overall CO2 emission. However, the method of maximizing the utilization of renewable energy needs consideration.
Utilizing water electrolysis is one of considered solution. The concept is to create hydrogen through water electrolysis using excess power produced by renewable energy. Then, produced hydrogen can be used in various fields.
In order to maximize utilization of renewable energy with water electrolysis, three attributes should be considered for water electrolysis; High pressure, large surface area, and high current density.
The following presentation contains three topics; 1. An introduction of latest research and development made in Korea on water electrolysis including PEM water electrolysis, 2. PEM water electrolysis research in Korea, led by Elchemtech and 3. Research conducted by Elchemtech on how to reach the target goal; large active area (3,000cm2), high current density (3A/cm2) and high pressure (350bar).
(Invited Plenary) Electrocatalysis in PEFCs – limitations in the Performance of the Hydrogen Oxidation and Oxygen Reduction Reactions
Authors: Kucernak Anthony 
Published: February 2020

An alternative approach to the rotating disk electrode (RDE) for characterising fuel cell electrocatalysts has been recently demonstrated[1, 2]. The approach combines high mass transport with a flat, uniform, and homogeneous catalyst deposition process, well suited for studying intrinsic catalyst properties at realistic operating conditions of a polymer electrolyte fuel cell (PEFC). Uniform catalyst layers were produced with loadings as low as 0.16 μgPt cm-2 and thicknesses as low as 200 nm, Figure 1. Such ultra thin catalyst layers are considered advantageous to minimize internal resistances and mass transport limitations leading to very high performance at low platinum loadings. Modelling of the associated diffusion field suggests that such high performance is enabled by fast lateral diffusion within the electrode. The electrodes operate over a wide potential range with insignificant mass transport losses, allowing the study of the oxygen reduction reaction (ORR) and hydrogen oxidation reaction (HOR) at high overpotentials. For the HOR, geometric current densities as high as 5.7 A cm-2
Geo were experimentally achieved at a loading of 10.15 μgPt cm-2 at room temperature (561 A mgPt
-1), which is three orders of magnitude higher than current densities achievable with the RDE. These currents correspond to a specific current densities of 600 ± 60 mA cm-2
Spec, although this maximum appears to be related - to the hydrogen adsorption process. For the ORR, electrodes produced a specific current density of 31 ± 9 mA cm-2
Spec at a potential of 0.65 V vs. RHE (28 A mg-1), Figure 2. The mass activities of Pt/C catalysts towards the ORR was found to exceed a range of literature PEFC mass activities across the entire potential range. This paper will discuss the lessons that can be learnt from these electrocatalytic studies and what they mean in terms of ultimate performance of fuel cells utilising precious metal catalysts.
[1] C.M. Zalitis, D. Kramer, J. Sharman, E. Wright, A.R. Kucernak, Pt Nano-Particle Performance for PEFC Reactions At Low Catalyst Loading and High Reactant Mass Transport, in: Polymer Electrolyte Fuel Cells 13, 2013, pp. 39-47.
[2] C.M. Zalitis, D. Kramer, A.R. Kucernak, Electrocatalytic performance of fuel cell reactions at low catalyst loading and high mass transport, Physical Chemistry Chemical Physics, 15 (2013) 4329-4340.

Figure 1
(Invited) Mixed Conducting Layered Oxides for Energy Storage: Challenges and Their Mitigation
Authors: Manthiram Arumugam 
Published: February 2020

Lithium-ion batteries have aided the revolution in portable electronic devices, and they are now being intensively pursued for electric vehicles and grid storage. Cost, safety, cycle life, energy, power, and environmental impact are the major factors for adopting a specific battery chemistry for a specific application, and often tradeoffs among the factors are needed in the selection. Although the layered LiMO2 (M = Ni and Co) oxides with mixed lithium-ion and electronic conductivity were first demonstrated more than 30 years ago as a lithium-insertion host, they still remain to be the dominant candidate for lithium-ion technology due to several appealing features displayed by them. With an aim to increase the charge-storage capacity and energy density, layered oxides with a high Ni content (> 50%) are now at the forefront in the battery industry around the world. However, compositions with high Ni content are hampered by high surface reactivity with the organic liquid electrolyte and the consequent impedance rise and fast capacity fade during cycling. Furthermore, they also suffer from high surface reactivity with ambient air, forming lithium hydroxide and lithium carbonate on the particle surface and thereby hampering the electrode fabrication process. A firm fundamental understanding of the origin of the fast capacity fade with advanced characterization methodologies and design and development of nickel-rich cathode compositions with robustness in contact with the liquid electrolyte and ambient air are critically needed to make the technology practically move forward. Accordingly, this presentation will focus on the characterization of nickel-rich layered oxides with advanced surface techniques and development of less reactive compositions with robust surface structures.
To develop a fundamental understanding of the degradation mechanisms, the nickel-rich layered oxide cathodes are investigated before and after long-term cycling in full cells with X-ray photoelectron spectroscopy (XPS), time-of-flight – secondary ion mass spectroscopy (TOF-SIMS), and high-resolution transmission electron microscopy. In-depth surface characterization as a function of sputtering time and cross-sectional analyses reveal that surface active mass dissolution caused by the acidic species in the electrolyte during cell operation and migration of dissolved metal ions from the cathode to the graphite anode cause impedance rise at the graphite anode, lithium dendrite growth, and capacity fade. Utilizing the in-depth understanding gained, stabilized full cells are designed and the degradation is being mitigated. Promise of cathode compositions with Ni contents as high as 94% and capacities as high as ~ 220 mAh/g with high power capability will be presented. The progress paves the way to design and develop high-power lithium-ion cells with high volumetric and gravimetric energy densities for portable, vehicle, and grid storage applications.
(Invited) Robust and Active Mixed-Conducting Electrodes for Intermediate-Temperature Fuel Cells
Authors: Chen Yu , Chen Dongchang , Ding Dong , Liu Meilin 
Published: February 2020

Intermediate-temperature solid oxide fuel cells have potential to be the cleanest and most efficient options for cost-effective utilization of a wide variety of fuels, from hydrogen to hydrocarbons, coal gas, and renewable fuels. They are ideally suited for distributed generation (which may be integrated with smart grids). To make these fuel cells economically competitive and commercially viable, however, several materials challenges must be overcome. One of them is the creation of durable, low-cost cathode materials and nanostructures of high electro-catalytic activity for oxygen reduction reaction at intermediate temperatures. Another challenge is the development of multi-functional anodes enabling efficient reforming of hydrocarbon fuels (e.g., methane) and directly operation on readily available fuels (e.g., natural gas) at intermediate temperatures. In this presentation, we will highlight an effective approach to fabrication of high-performance catalysts coated electrodes of dramatically enhanced electro-catalytic activity and durability, as schematically shown in Figure 1. The concept of modifying electrode surface through solution infiltration of a catalyst to create unique hybrid electrode structure (e.g., exsoluted nanoparticles on a conformal coating) are readily applicable to other electrochemical energy storage and conversion systems, including metal-air batteries, supercapacitors, and electrolyzers.
Figure 1. Schematic for a high-performance cathode consists of the state-of-the-art cathode backbone (e.g., LSCF) and a durable catalyst (conformal coating and exsoluted nanoparticles) against various contaminants, making effective use of the best properties of two different materials (backbone and catalyst).

Figure 1
(Invited) Understanding Anode and Cathode Reaction Mechanisms for Proton Conducting Intermediate Temperature Solid Oxide Fuel Cells
Authors: Sun Shichen , Cheng Zhe 
Published: February 2020

The anode and cathode reaction processes for conventional solid oxide fuel cells (SOFC) have been widely studied. In comparison, there are many unknowns about the basic electrochemical behaviors and mechanisms for the anode and cathode reactions of proton conducting SOFC, especially at intermediate temperature (IT) range of ~400-700oC when the cells approach ideal proton conducting behaviors. At intermediate temperature, due to the change of the dominating ionic conducting species from oxide ion to proton, the fundamental reaction pathways would change for both the anode and cathode reactions. Accompanied with such changes, many interesting electrochemical behaviors arise for proton conducting IT-SOFC. For example, it is well known that the Ni-based cermet anode for conventional oxide ion SOFC are susceptible to poisoning by sub-ppm level hydrogen sulfide (H2S) and not very sensitive to carbon monoxide (CO). In comparison, literature seems to suggest that the Ni-proton conducting oxide cermet as the anode for proton conducting IT-SOFC shows much better resistance against low ppm-level H2S but is poisoned by percentage level CO. This study aims to understand the fundamental reaction processes for both the anode (hydrogen electrode) and cathode (air electrode) of proton conducting IT-SOFCs. Electrochemical tests are carried out based on the concept of “controlled poisoning”, which is to selectively slow down a specific part of the electrode reaction using a specially chosen “poison” in order to help understand the fundamentals about the electrode reactions for proton-conducting IT-SOFCs. In particular, for the anode, H2S is used as a “Ni poison” and CO2 as a proton conducting oxide poison, while for the cathode, either H2O or CO2 is used. The measured electrochemical behaviors for different anode- or electrolyte-supported full cells and symmetrical cells including those with patterned (metal) electrodes are compared with those of conventional oxide ion based SOFCs. The results for those experiments aimed at understanding the similarity and differences between proton conducting SOFC and conventional oxide ion conducting SOFC will be presented, and their implications on the anode and cathode reaction mechanisms and the roles (including electrocatalytic roles) of proton conducting oxides in those electrode reactions for proton conducting IT-SOFC will be discussed.
(Invited) The ARPA-E Ionics Program: Separators to Enable the Cycling of Lithium Metal
Authors: Albertus Paul S. , Babinec Susan J. , Litzelman Scott J. 
Published: February 2020

ARPA-E has funded five themed Programs and spent >$200 million on advancing energy storage technology since its inception. Unfortunately, the ultimate impacts of some of the technical advances made within ARPA-E efforts, as well as advances developed outside of ARPA-E, are hindered by constraints arising from separator cost and performance limitations. In response to this situation, ARPA-E launched the IONICS (Integration and Optimization of Novel Ion-Conducing Solids) program in 2016. The 16 teams in the program are focused on developing breakthrough separators that would be broadly enabling in different areas of electrochemical technology, and also amenable to cost effective manufacturing. The projects include both polymer and inorganic ion conducting separators that enable electrode chemistries that have been previously unsuccessful in practical devices. Project teams are focused on overcoming property tradeoffs to achieve a full set of required attributes, including conductivity, selectivity, stability, mechanical properties, manufacturability, cost, and others. This contrasts with a common approach of optimizing a single variable at the expense of others. The IONICS focus is on solids rather than liquids, due to inherent advantages in selectivity and mechanical properties offered by solids.
The IONICS program has three areas: (1) Li+ conductors that enable the cycling of the lithium metal electrode at 25°C and at conditions required for high-energy cells, (2) highly selective polymer separators for flow batteries, and (3) anion-conducting polymer separators for use in alkaline fuel cells and electrolyzers. This talk will focus on area (1), where the cycling of lithium metal at conditions relevant to high-energy cells still has not been shown, despite decades of research. Highlights of the talk will include: (1) presentation of a new figure depicting state-of-the-art cycling of lithium metal in both industry and research institutions, which reveals tradeoffs among the critical cycling metrics relevant to high-energy cells (i.e., cumulative capacity throughput, current density, and per-cycle areal capacity), (2) suggestion of test protocols that ensure proper interpretation of cycling data, and especially that electronic and ionic currents are distinguished, (3) the economics of film manufacturing, and the pathways to achieve the aggressive IONICS cost targets (<10 $/m2) required for widespread adoption for transportation or grid applications, and (4) the technical approaches being pursued in the program, with a focus on ceramics.