Article
Chemistry, Physical
Rohan Kumar, K. A. Subramanian
Summary: This paper investigates the effects of oxygen-enriched air, along with other operating parameters, on the performance of a hydrogen-fuelled proton exchange membrane (PEM) fuel cell. The results show that 45% oxygen enrichment is optimal, and the stack temperature plays a significant role in performance improvement. The voltage efficiency and power output are improved with 45% oxygen-enriched air. Electrochemical impedance spectroscopy reveals the impedance behavior of the fuel cell under variable current demand.
INTERNATIONAL JOURNAL OF HYDROGEN ENERGY
(2023)
Article
Chemistry, Analytical
Andrei Kulikovsky
Summary: An analytical model for the concentration/pressure impedance on the cathode side of a PEM fuel cell has been developed, with analytical solution derived for the zeta impedance. Simple equations for the static point of zeta impedance have been obtained, allowing estimation of oxygen transport coefficients. The qualitative resemblance between the model and experimental zeta-spectrum has been demonstrated.
JOURNAL OF ELECTROANALYTICAL CHEMISTRY
(2021)
Article
Chemistry, Analytical
Samuel Cruz-Manzo, Paul Greenwood
Summary: This study proposes a new electrochemical impedance model for predicting oxygen diffusion resistance in PEFCs, which is validated through EIS measurements in different layers of the PEFC. The results show that the estimated oxygen diffusion resistances are distributed in the cathode catalyst layer (CCL) and gas diffusion layer (GDL) of the PEFC, providing a deeper understanding of the influence of electrochemical mechanisms on EIS measurements.
JOURNAL OF ELECTROANALYTICAL CHEMISTRY
(2021)
Article
Energy & Fuels
Rui Yang, Johnbosco Yesuraj, Kibum Kim
Summary: This study proposed four different types of flow paths inside a PEMEC and examined the effect of the flow path shape on the hydrogen evolution reaction. The experimental results showed that the parallel grid flow field had the highest current density and hydrogen production at the optimum operating temperature. Computational fluid dynamics analysis confirmed that the parallel grid flow field had an advantageous path shape for electrolyte distribution. The findings of this study can be used as a reference for PEMEC research in terms of selecting suitable flow field geometries and temperatures.
Article
Electrochemistry
Nammin Lee, Masoomeh Ghasemi, Bonghyun Kim, Seungbeen Choe, Kisung Lim, Seung Woo Lee, Seung Soon Jang, Hyunchul Ju
Summary: Air-cooled fuel cell systems are recognized as suitable technology for drone and aviation applications due to their lightweight and simple design. However, compared to liquid-cooled systems, they suffer from low specific power and unstable performance, mainly due to severe electrolyte dehydration and nonuniform current density and temperature profiles.
JOURNAL OF THE ELECTROCHEMICAL SOCIETY
(2021)
Article
Electrochemistry
Christophe Gerling, Matthias Hanauer, Ulrich Berner, K. Andreas Friedrich
Summary: This paper focuses on the performance optimization of membrane electrode assemblies of PEM fuel cells by accurately characterizing and modeling relevant mechanisms. Various operating conditions are studied, leading to estimation of activation energies and evaluation of resistance changes. The study highlights the importance of accurate characterization in enhancing fuel cell performance.
JOURNAL OF THE ELECTROCHEMICAL SOCIETY
(2021)
Article
Chemistry, Physical
K. M. Gitushi, M. L. Blaylock, L. E. Klebanoff
Summary: This study investigates the effects of hydrogen leaks on the flammable region inside a fuel cell room using computational fluid dynamics modeling. The results show that the size of the flammable region is initially limited by self-induced entrainment and recirculation of air caused by the buoyant rising of hydrogen. Ventilation has an impact on the stability of the flammable region. By adjusting the ventilation rate and leak level, timely hydrogen evacuation and leak detection can be achieved.
INTERNATIONAL JOURNAL OF HYDROGEN ENERGY
(2022)
Article
Biochemistry & Molecular Biology
Andrei Kulikovsky
Summary: In this study, a model for concentration/pressure impedance zeta of the cathode catalyst layer of a low-Pt PEM fuel cell is developed. The model is based on transient oxygen mass transport equations through a single pore with a thin Nafion film covering. An analytical solution for zeta-impedance at high cell current is derived for fast fitting of experimental data. This technique is a useful alternative to standard EIS.
Article
Electrochemistry
Christophe Gerling, Matthias Hanauer, Ulrich Berner, K. Andreas Friedrich
Summary: The low-frequency inductive features in PEMFC have been investigated by differential measurements and numerical simulation. The contributions of slow platinum oxide kinetics and ionomer humidification are examined, with the latter found to be more relevant at medium to high currents. The inductive loops exhibit a strong dependence on current density and relative gas humidity, and can reach over 150 mV dec(-1) at high load.
JOURNAL OF THE ELECTROCHEMICAL SOCIETY
(2023)
Article
Chemistry, Physical
Dean E. Glass, Vicente Galvan, Marc Iulliucci, G. K. Surya Prakash
Summary: This study investigates the role of partially fluorinated carbon (CFx) supported platinum nanoparticles as electrodes in a proton exchange membrane fuel cell (PEMFC) for hydrogen fuel cell applications. The results show that CFx, as a platinum catalyst support, exhibits better oxygen reduction reaction (ORR) kinetics compared to the widely used Vulcan Carbon (XC-72R). CFx catalysts display higher ORR kinetics at lower platinum loadings, while XC-72R displays higher kinetics at higher platinum loadings. The PEMFC tests reveal that CFx supported catalysts exhibit a 20% increase in fuel cell performance and an 11% decrease in charge transfer resistance compared to XC-72R supported catalysts. Furthermore, using CFx as the support for both anode and cathode electrodes leads to a 15% increase in power density compared to XC-72R supported catalysts.
JOURNAL OF POWER SOURCES
(2022)
Article
Chemistry, Physical
Babak Ghorbani, Jake Devaal, Greg Afonso, Krishna Vijayaraghavan
Summary: This paper analyzes the electrochemical impedance spectra (EIS) of commercial proton exchange membrane fuel cell stacks to study the relationship between oxygen concentration and EIS response within individual cells. The experiments show a proportional relationship between the Warburg parameter in the equivalent circuit model and hydrogen crossover, with the parameter increasing significantly with reduced cathode air flows. This relationship can be used to estimate the number of large-leaky cells and the total hydrogen crossover rate.
INTERNATIONAL JOURNAL OF HYDROGEN ENERGY
(2023)
Article
Chemistry, Physical
Reza Poursaeid Zahed, Javad Mahmoudimehr, Nima Amanifard
Summary: The study aims to improve oxygen transfer in Polymer Electrolyte Membrane Fuel Cells (PEMFCs) by converting the flat Gas Diffusion Layer (GDL) to a corrugated one. The results show that the effectiveness of GDL corrugation in enhancing oxygen transfer depends on the corrugation amplitude and period, as well as operating pressure and oxygen purity. The power of the cell can increase up to 4.08% with GDL corrugation.
INTERNATIONAL JOURNAL OF HYDROGEN ENERGY
(2023)
Article
Energy & Fuels
Jian Dang, Fuyuan Yang, Yangyang Li, Yingpeng Zhao, Minggao Ouyang, Song Hu
Summary: A multi-physical model of a high pressure single-cell electrolyzer is established and the heat transfer, mass transfer, and electrochemical processes are described. The water permeation flow rate is accurately simulated using experimental data, and the double layer effect and mass transfer lag effect are considered. Consistency in polarization curves is observed at different temperatures and high cathode pressure.
Article
Chemistry, Physical
Johannes Geiling, Michael Steinberger, Florian Ortner, Roman Seyfried, Andreas Nuss, Felix Uhrig, Christopher Lange, Richard Oschsner, Peter Wasserscheid, Martin Maerz, Patrick Preuster
Summary: The study shows that liquid organic hydrogen carriers can be a promising alternative for hydrogen storage, and demonstrates successful dynamic combined operation of LOHC reactor and PEM fuel cell. The fuel cell operated stably for 4.5 hours, with carbon hydrocarbon contaminants removed through activated carbon filtering without any detectable impairment or degradation.
INTERNATIONAL JOURNAL OF HYDROGEN ENERGY
(2021)
Review
Chemistry, Physical
Saeed Sahebdelfar, Maryam Takht Ravanchi
Summary: The removal of CO from hydrogen derived from hydrocarbon and methanol can be achieved through various methods, such as pressure swing adsorption, membrane separation, selective methanation, and preferntial oxidation. Among them, PROX is considered the best method for small scale portable fuel processors due to its rapid reaction rate and mild operation conditions. Extensive research is being conducted to improve catalyst activity and expand the temperature range for the reaction.
INTERNATIONAL JOURNAL OF HYDROGEN ENERGY
(2023)
Article
Chemistry, Physical
Tianyu Chen, Zhibin Lu, Guangjin Zeng, Yongmin Xie, Jie Xiao, Zhifeng Xu
Summary: The study introduces a high-performance LSGM electrolyte-supported tubular DC-SOFC stack for portable applications, which shows great potential in developing into high-performing, efficient, and environmentally friendly portable power sources for distributed applications.
JOURNAL OF POWER SOURCES
(2024)
Article
Chemistry, Physical
Wenbin Tong, Yili Chen, Shijie Gong, Shaokun Zhu, Jie Tian, Jiaqian Qin, Wenyong Chen, Shuanghong Chen
Summary: In this study, a three-dimensional porous NiO interface layer with enhanced anode dynamics is fabricated, forming a Schottky contact with the zinc substrate, allowing rapid and uniform zinc plating both inside and below the interface layer. The resulting NiO@Zn exhibits exceptional stability and high capacity retention.
JOURNAL OF POWER SOURCES
(2024)
Article
Chemistry, Physical
Yafeng Bai, Kaidi Li, Liying Wang, Yang Gao, Xuesong Li, Xijia Yang, Wei Lu
Summary: In this study, a flexible zinc ion supercapacitor with gel electrolytes, porous alpha-MnO2@reduced graphene oxide cathode, and activated carbon/carbon cloth anode was developed. The device exhibits excellent electrochemical performance and stability, even at low temperatures, with a high cycle retention rate after 5000 cycles.
JOURNAL OF POWER SOURCES
(2024)
Article
Chemistry, Physical
Anmol Jnawali, Matt D. R. Kok, Francesco Iacoviello, Daniel J. L. Brett, Paul R. Shearing
Summary: This article presents the results of a systematic study on the electrochemical performance and mechanical changes in two types of commercial batteries with different anode chemistry. The study reveals that the swelling of anode layers in batteries with silicon-based components causes deformations in the jelly roll structure, but the presence of a small percentage of silicon does not significantly impact the cycling performance of the cells within the relevant state-of-health range for electric vehicles (EVs). The research suggests that there is room for improving the cell capacities by increasing the silicon loading in composite anodes to meet the increasing demands on EVs.
JOURNAL OF POWER SOURCES
(2024)
Article
Chemistry, Physical
Yohandys A. Zulueta, My Phuong Pham-Ho, Minh Tho Nguyen
Summary: Advanced atomistic simulations were used to study ion transport in the Na- and K-doped lithium disilicate Li2Si2O5. The results showed that Na and K doping significantly enhanced Li ion diffusion and conduction in the material.
JOURNAL OF POWER SOURCES
(2024)
Article
Chemistry, Physical
Zongying Han, Hui Dong, Yanru Yang, Hao Yu, Zhibin Yang
Summary: An efficient phase inversion-impregnation approach is developed to fabricate BaO-decorated Ni8 mol% YSZ anode-supported tubular solid oxide fuel cells (SOFCs) with anti-coking properties. BaO nanoislands are successfully introduced inside the Ni-YSZ anode, leading to higher peak power densities and improved stability in methane fuel. Density functional theory calculations suggest that the loading of BaO nanoislands facilitates carbon elimination by capturing and dissociating H2O molecules to generate OH.
JOURNAL OF POWER SOURCES
(2024)
Article
Chemistry, Physical
Suresh Mamidi, Dan Na, Baeksang Yoon, Henu Sharma, Anil D. Pathak, Kisor Kumar Sahu, Dae Young Lee, Cheul-Ro Lee, Inseok Seo
Summary: Li-CO2 batteries, which utilize CO2 and have a high energy density, are hindered in practical applications due to slow kinetics and safety hazards. This study introduces a stable and highly conductive ceramic-based solid electrolyte and a metal-organic framework catalyst to improve the safety and performance of Li-CO2 batteries. The optimized Li-CO2 cell shows outstanding specific capacity and cycle life, and the post-cycling analysis reveals the degradation mechanism of the electrodes. First-principles calculations based on density functional theory are also performed to understand the interactions between the catalyst and the host electrode. This research demonstrates the potential of MOF cathode catalyst for stable operation in Li-CO2 batteries.
JOURNAL OF POWER SOURCES
(2024)
Article
Chemistry, Physical
Ganghua Xiang, Zhihuan Qiu, Huilong Fei, Zhigang Liu, Shuangfeng Yin, Yuen Wu
Summary: In this study, a CeFeOx-supported Pt single atoms and subnanometric clusters catalyst was developed, which exhibits enhanced catalytic activity and stability for the preferential oxidation of CO in H2-rich stream through synergistic effect.
JOURNAL OF POWER SOURCES
(2024)
Article
Chemistry, Physical
Dimitrios Chatzogiannakis, Marcus Fehse, Maria Angeles Cabanero, Natalia Romano, Ashley Black, Damien Saurel, M. Rosa Palacin, Montse Casas-Cabanas
Summary: By coupling electrochemical testing to operando synchrotron based X-ray absorption and powder diffraction experiments, blended positive electrodes consisting of LiMn2O4 spinel (LMO) and layered LiNi0.5Mn0.3Co0.2O2 (NMC) were studied to understand their redox mechanism. It was found that blending NMC with LMO can enhance energy density at high rates, with the blend containing 25% LMO showing the best performance. Testing with a special electrochemical setup revealed that the effective current load on each blend component can vary significantly from the nominal rate and also changes with SoC. Operando studies allowed monitoring of the oxidation state evolution and changes in crystal structure, in line with the expected behavior of individual components considering their electrochemical current loads.
JOURNAL OF POWER SOURCES
(2024)
Article
Chemistry, Physical
Chiara Cementon, Daniel Dewar, Thrinathreddy Ramireddy, Michael Brennan, Alexey M. Glushenkov
Summary: This Perspective discusses the specific power and power density of lithium-ion capacitors, highlighting the fact that their power characteristics are often underestimated. Through analysis, it is found that lithium-ion capacitors can usually achieve power densities superior to electrochemical supercapacitors, making them excellent alternatives to supercapacitors.
JOURNAL OF POWER SOURCES
(2024)
Article
Chemistry, Physical
Weihao Wang, Hao Yu, Li Ma, Youquan Zhang, Yuejiao Chen, Libao Chen, Guichao Kuang, Liangjun Zhou, Weifeng Wei
Summary: This study achieved an improved electrolyte with excellent low-temperature and high-voltage performance by regulating the Li+ solvation structure and highly concentrating it. The electrolyte exhibited outstanding oxidation potential and high ionic conductivity under low temperature and high voltage conditions, providing a promising approach for the practical application of high-voltage LIBs.
JOURNAL OF POWER SOURCES
(2024)
Article
Chemistry, Physical
Martin Bures, Dan Gotz, Jiri Charvat, Milos Svoboda, Jaromir Pocedic, Juraj Kosek, Alexandr Zubov, Petr Mazur
Summary: Vanadium redox flow battery is a promising energy storage solution with long-term durability, non-flammability, and high overall efficiency. Researchers have developed a mathematical model to simulate the charge-discharge cycling of the battery, and found that hydraulic connection of electrolyte tanks is the most effective strategy to reduce capacity losses, achieving a 69% reduction.
JOURNAL OF POWER SOURCES
(2024)
Article
Chemistry, Physical
M. Rodriguez-Gomez, J. Campo, A. Orera, F. de La Fuente, J. Valenciano, H. Fricke, D. S. Hussey, Y. Chen, D. Yu, K. An, A. Larrea
Summary: In this study, we analysed the operando performance of industrial lead cells using neutron diffraction experiments. The experiments revealed the evolution of different phases in the positive electrode, showed significant inhomogeneity of phase distribution inside the electrode, and estimated the energy efficiency of the cells.
JOURNAL OF POWER SOURCES
(2024)
Article
Chemistry, Physical
Jiawei Liu, Chenpeng Wang, Yue Yao, Hao Ye, Yinglong Liu, Yingli Liu, Xiaoru Xu, Zhicong Chen, Huazheng Yang, Gang Wu, Libin Lei, Chao Wang, Bo Liang
Summary: The study focuses on utilizing double conductive Ni-pads as anode collectors in micro-tubular solid oxide fuel cells. The simulation results show excellent performance and stability of DCNPs, and also highlight the potential applications in various fields.
JOURNAL OF POWER SOURCES
(2024)
Article
Chemistry, Physical
Yang Wang, Kangjie Zhou, Lang Cui, Jiabing Mei, Shengnan Li, Le Li, Wei Fan, Longsheng Zhang, Tianxi Liu
Summary: This study presents a polyimide sandwiched separator (s-PIF) for improving the cycling stability of Li-metal batteries. The s-PIF separator exhibits superior mechanical property, electrolyte adsorption/retention and ion conductivity, and enables dendrite-free Li plating/stripping process.
JOURNAL OF POWER SOURCES
(2024)