Article
Chemistry, Physical
David Bernhard, Thomas Kadyk, Ulrike Krewer, Sebastian Kirsch
Summary: In this study, proton exchange membrane fuel cell cathodes were degraded using accelerated stress tests. The analysis showed that unspecified voltage losses exist not only at high current densities, but already at low current densities, and these losses increase linearly with decreasing half cell voltage.
INTERNATIONAL JOURNAL OF HYDROGEN ENERGY
(2021)
Article
Chemistry, Physical
Michael Obermaier, Krzysztof Jozwiak, Markus Rauber, Andreas Bauer, Christina Scheu
Summary: The knowledge gained from fuel cell degradation analysis is critical for achieving durability targets and commercializing polymer electrolyte membrane fuel cells, depending on the dominant degradation mode. This study systematically investigates four potential methods for detecting pinholes in the polymer membrane. Detection limits, material system impacts, and other relevant factors are discussed to optimize defect detection and make recommendations for practical application.
JOURNAL OF POWER SOURCES
(2021)
Article
Chemistry, Physical
David Bernhard, Thomas Kadyk, Sebastian Kirsch, Hannes Scholz, Ulrike Krewer
Summary: This work presents a model for predicting and analyzing voltage losses in proton exchange membrane fuel cells during accelerated stress testing. The model consists of two submodels - one describing the degradation of the catalyst active surface using a statistical physics-based approach, and another incorporating the degradation of catalyst activity. The model allows the description of catalyst surface reduction, changes in Tafel slope and exchange current density, and voltage losses.
JOURNAL OF POWER SOURCES
(2023)
Article
Thermodynamics
Ziliang Gao, Fengfeng Liu, Jinzhan Su, Liejin Guo, Hongtan Liu
Summary: This article investigates the voltage reversal and dehydration phenomenon of a proton exchange membrane fuel cell (PEMFC) during the start-up process. The reverse voltage occurs under conditions of low relative humidity, high current density load, and high hydrogen stoichiometry at low humidity. Through time constant analysis, it is observed that dehydration on the anode side of the membrane electrode leads to an instantaneous increase of high frequency resistance (HFR), revealing the process mechanism of voltage reversal. Finally, a startup strategy is suggested to reduce or avoid reverse voltage occurrence.
ENERGY CONVERSION AND MANAGEMENT
(2022)
Article
Electrochemistry
Andre J. Spears, Tommy Rockward, Rangachary Mukundan, Fernando Garzon
Summary: Membrane chemical degradation significantly affects fuel cell durability, with factors such as ultra-low Pt electrode loadings and heterogeneous radical formation sites impacting degradation rate. Variations in catalyst layer thickness, ionomer to carbon ratio, and carbon support types also influence membrane degradation rates.
JOURNAL OF THE ELECTROCHEMICAL SOCIETY
(2021)
Article
Chemistry, Physical
Rui B. Ferreira, D. S. Falcao, A. M. F. R. Pinto
Summary: The study simulated membrane chemical degradation in proton exchange membrane (PEM) fuel cells using computational fluid dynamics (CFD). Results showed that degradation is accelerated by increased voltage, temperature, pressure, decreased reactant humidity and membrane thickness. Additionally, degradation is more severe with higher oxygen pressure and more heterogeneous with less uniform oxygen distribution.
INTERNATIONAL JOURNAL OF HYDROGEN ENERGY
(2021)
Article
Chemistry, Physical
Zhenbin Liu, Shuang Wang, Lei Xia, Shumeng Guan, Fen Zhou, Jinting Tan, Mu Pan
Summary: The study found that the breakdown voltage of catalyst coated membranes (CCMs) is significantly lower than that of uncoated proton exchange membranes (PEM), and the higher the platinum (Pt) loading, the lower the breakdown voltage. When the catalyst layer (CL) side of the single-side CL coated CCM is connected to the positive pole, the breakdown voltage decreases and leads to thermal breakdown.
INTERNATIONAL JOURNAL OF HYDROGEN ENERGY
(2022)
Article
Chemistry, Physical
J. O. Leader, Y. Yue, M. R. Walluk, T. A. Trabold
Summary: High-temperature proton exchange membrane fuel cells (HT-PEM) have advantages such as improved fuel impurity tolerance and increased electrode kinetics. This study investigated the voltage degradation of HT-PEM fuel cells operating at 200 degrees C under continuous load conditions and during start-stop cycling. The results showed relatively high degradation rates, but with decreasing average degradation rates over cycles.
INTERNATIONAL JOURNAL OF HYDROGEN ENERGY
(2022)
Article
Electrochemistry
Wenbin Yang, Jiangtao Geng, Jiajun Wang, Zhigang Shao, Xiaoping Qin
Summary: Considering the high initial cost of proton exchange membrane fuel cells, improving their durability is crucial for their commercialization. This work proposes a performance recovery strategy by reversing the cathode and anode and then operating under a high current density load. The experimental results show significant improvement in cell performance after implementing the recovery strategy, with a recovery rate of 54% at 800 mA cm-2. The mechanisms of performance recovery include reduction of platinum oxide, desorption/removal of sulfate, and removal of accumulated water. The main mechanisms of irreversible performance attenuation are the coarsening of Pt particles, formation of Pt band, carbon support corrosion, and CL mechanical degradation. These findings provide insights for designing recovery strategies and enhancing electrode materials and structures.
ELECTROCHIMICA ACTA
(2023)
Article
Engineering, Electrical & Electronic
Xinyang Hao, Issam Salhi, Salah Laghrouche, Youcef Ait-Amirat, Abdesslem Djerdir
Summary: This article proposes a novel and robust nonlinear controller for a four-phase interleaved boost converter combined with proton exchange membrane fuel cells. The controller shows strong robustness and high dynamic features, and is tuned and optimized using a particle swarm optimization algorithm.
IEEE TRANSACTIONS ON POWER ELECTRONICS
(2022)
Article
Engineering, Electrical & Electronic
Meiling Yue, Khaled Benaggoune, Jianwen Meng, Demba Diallo
Summary: In this article, a digital twin for predicting fuel cell degradation using a transfer learning method is proposed. A multi-input data-driven behavior model of fuel cell degradation is constructed based on a connected convolutional neural network and long short-term memory network to capture spatial and temporal characteristics hidden in the data. Transfer learning is applied to leverage knowledge from historical datasets for reliable real-time prediction, especially in the early stage. The developed digital twin is cross-validated using two fuel cell aging experiment datasets, demonstrating the effectiveness and generalizability of the approach.
IEEE TRANSACTIONS ON TRANSPORTATION ELECTRIFICATION
(2023)
Article
Chemistry, Physical
Weibo Zheng, Liangfei Xu, Zunyan Hu, Yujie Ding, Jianqiu Li, Minggao Ouyang
Summary: This study proposes a numerical method to simulate the formation of pinholes in polymer electrolyte fuel cells, which enhances the accuracy of the chemical degradation model in predicting macroscopic properties. It systemically investigates the effects of temperature, pressure, and relative humidity on chemical degradation, showing that degradation rate increases with elevated temperatures and pressures, and is more severe at moderate relative humidity.
JOURNAL OF POWER SOURCES
(2021)
Article
Chemistry, Physical
Omer Sahin, Abdurrahman Akdag, Sabit Horoz, Arzu Ekinci
Summary: This study investigates the activity of catalysts synthesized from platinum and molybdenum alloys as cathode electrocatalysts in the PEMFC. The structural properties of the catalysts were analyzed, and their electrochemical properties were assessed. The performance of the cathodes under different conditions was examined, and the use of ozone as an oxidizing agent was explored. It was found that the catalyst exhibited higher catalytic activity at higher temperatures.
INTERNATIONAL JOURNAL OF HYDROGEN ENERGY
(2023)
Article
Energy & Fuels
Peter Reithuber, Florian Poimer, Stefan Brandstaetter, Eberhard Schutting, Simon Buchberger, Alexander Trattner, Helmut Eichlseder
Summary: This research investigates the impact of nitrogen monoxide (NO) on the performance and durability of proton exchange membrane (PEM) fuel cell vehicles. The study finds that NO leads to a decrease in cell voltage due to reversible adsorption on the platinum catalyst. Different concentrations and exposure times of NO are evaluated to assess the effects on the fuel cell system. The research also proposes voltage recovery and mitigation strategies, identifies the most promising recovery strategy, and discusses the overall system degradation caused by NO.
Review
Energy & Fuels
J. Aubry, N. Yousfi Steiner, S. Morando, N. Zerhouni, D. Hissel
Summary: Fuel cell durability is crucial for the technology industrialization in the automotive sector, and fault tolerant control process can improve the durability by detecting and correcting fuel cell faults in real time. This article focuses on the diagnosis part of fault tolerant control in vehicle application, including real time measurements, useful information extraction, and classification. Vehicle applications have various constraints such as cost reduction, hydrogen usage, computation limitations, and safety regulations.
Article
Chemistry, Physical
Li Wang, Viktoriia A. Saveleva, Mohammad J. Eslamibidgoli, Denis Antipin, Corinne Bouillet, Indro Biswas, Aldo S. Gago, Seyed S. Hosseiny, Pawel Gazdzicki, Michael H. Eikerling, Elena R. Savinova, K. Andreas Friedrich
Summary: Hydrogen production through water electrolysis using renewable electricity is crucial for the future defossilized energy era. In this study, an anion exchange membrane electrolyzer with Fe-doped Ni hydroxide as an anode catalyst was found to exhibit similar performance as proton exchange membrane electrolyzers, with excellent oxygen evolution reaction activity.
ACS APPLIED ENERGY MATERIALS
(2022)
Article
Engineering, Chemical
Elias Klemm, Carlos M. S. Lobo, Armin Loewe, Verena Schallhart, Stephan Renninger, Lara Waltersmann, Remi Costa, Andreas Schulz, Ralph-Uwe Dietrich, Lukas Moeltner, Vera Meynen, Alexander Sauer, K. Andreas Friedrich
Summary: The chemical industry needs to achieve carbon neutrality by 2050 by suppressing CO2 emissions from fossil sources. CHEMampere contributes to this goal by producing green chemicals using electricity-based CCU technologies in a decentralized manner.
CANADIAN JOURNAL OF CHEMICAL ENGINEERING
(2022)
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
Marius Tomberg, Marc P. P. Heddrich, S. Asif Ansar, K. Andreas Friedrich
Summary: Electrolysis systems with solid oxide cell (SOC) reactors have high efficiency and flexibility, and can achieve fast and robust transient operation through developed operation strategies. Experimental results show that using SOC systems can greatly reduce start-up time and temperature gradients, and achieve fast power modulation.
SUSTAINABLE ENERGY & FUELS
(2023)
Article
Chemistry, Analytical
Luca Cressa, Yanyan Sun, Dustin Andersen, Mathieu Gerard, Olivier De Castro, Dennis Kopljar, Maryam Nojabaee, Kaspar Andreas Friedrich, Guido Schmitz, Tom Wirtz, Santhana Eswara
Summary: The global transition to green energy highlights the importance of efficient and reliable energy storage systems. Advanced analysis and characterization of battery materials are crucial for understanding their properties and continued development. A new operando methodology has been developed to analyze solid-state batteries (SSBs) structurally and chemically during different stages of cycling. This method allows for analysis without transferring samples between instruments and provides a direct correlation between microstructure, chemical composition, and electrochemical performance.
ANALYTICAL CHEMISTRY
(2023)
Article
Chemistry, Multidisciplinary
Sebastian C. H. Bragulla, Julian Lorenz, Corinna Harms, Michael Wark, K. Andreas Friedrich
Summary: This study developed an ion chromatography (IC) method for quantitative trace analysis of ammonium in 0.1 M sulfuric acid electrolyte, and applied it to EAS gas-diffusion electrode (GDE) experiments with commercial chromium nitride as electrocatalyst. The IC method achieved a highly sensitive, versatile, and reliable analysis with a limit of quantification (LOQ) of 6 mu g l(-1) ammonium. The impacts of various factors on the quantitative analysis by IC were analyzed, and the practical guide provided is relevant for the field of EAS.
Article
Engineering, Chemical
Ziqi Xu, Vincent Wilke, Jagoda Justyna Chmielarz, Morawietz Tobias, Vladimir Atanasov, Aldo Saul Gago, Kaspar Andreas Friedrich
Summary: In this study, a new type of anion exchange membrane with a styrene-b-ethylene-b-butylene-b-styrene copolymer (SEBS) backbone and piperidinium functioned flexible ethylene oxide spacer structure as its side-chains (SEBS-P2O6) was developed. The membrane exhibited a hydroxide ion conductivity of 20.8 mS cm-1 at room temperature, higher than the previously obtained piperidinium functionalized SEBS membrane with 10.09 mS cm-1.
JOURNAL OF MEMBRANE SCIENCE
(2023)
Article
Electrochemistry
Chang Liu, Meital Shviro, Guido Bender, Aldo S. Gago, Tobias Morawietz, Michael J. Dzara, Indro Biswas, Pawel Gazdzicki, Zhenye Kang, Sarah F. Zaccarine, Svitlana Pylypenko, K. Andreas Friedrich, Marcelo Carmo, Werner Lehnert
Summary: The PTL/CL interface is crucial for the performance and efficiency of PEMWEs. This study compared the degradation of MEAs with uncoated and Ir-coated Ti PTLs during a 4000 h test. The results showed that the optimized interface formed with an Ir coating reduced the degradation of the MEA, without affecting the morphology change or oxidation of IrOx in the catalyst layer. Additionally, the ionomer loss and restructuring of the anodic MEA could also be reduced by the Ir coating of the PTL/CL interface. Optimizing the PTL/CL interface improves the performance and durability of PEMWEs.
JOURNAL OF THE ELECTROCHEMICAL SOCIETY
(2023)
Article
Multidisciplinary Sciences
Dmitry Galyamin, Jorge Torrero, Isabel Rodriguez, Manuel J. Kolb, Pilar Ferrer, Laura Pascual, Mohamed Abdel Salam, Diego Gianolio, Veronica Celorrio, Mohamed Mokhtar, Daniel Garcia Sanchez, Aldo Saul Gago, Kaspar Andreas Friedrich, Miguel A. Pena, Jose Antonio Alonso, Federico Calle-Vallejo, Maria Retuerto, Sergio Rojas
Summary: The study finds that low-ruthenium-content pyrochlores (R2MnRuO7, R = Y, Tb, and Dy) exhibit high activity and durability for the oxygen evolution reaction (OER) in acidic media. Among them, Y2MnRuO7 is the most stable catalyst, showing a voltage of 1.5 V at 10 mA cm(-2) for 40 h, or 5000 cycles up to 1.7 V. Experimental and computational results indicate that the excellent performance is attributed to the Ru sites embedded in RuMnOx surface layers. A water electrolyzer with Y2MnRuO7 and only 0.2 mgRu cm(-2) achieves a current density of 1 A cm(-2) at 1.75 V, remaining stable at 200 mA cm(-2) for over 24 h. These findings suggest further investigation on Ru catalysts with the goal of enhancing OER performance through a partial replacement of Ru with inexpensive cations. Ru-pyrochlores can serve as alternative anodes of PEM water electrolyzers, and their high performance is attributed to the Ru sites embedded in RuMnOx surface layers. The durability of a water electrolyzer with Y2MnRuO7 and only 0.2 mgRu cm(-2) has been successfully demonstrated.
NATURE COMMUNICATIONS
(2023)
Article
Chemistry, Physical
Jorge Torrero, Tobias Morawietz, Daniel Garcia Sanchez, Dmitry Galyamin, Maria Retuerto, Vlad Martin-Diaconescu, Sergio Rojas, Jose Antonio Alonso, Aldo Saul Gago, Kaspar Andreas Friedrich
Summary: In this study, an anode with reduced iridium loading (0.2 mg) compared to commercial proton exchange membrane water electrolysis (PEMWE) (2-3 mg) was developed, demonstrating high performance and stability for over 1000 hours. An advanced catalyst based on an Ir mixed oxide (Sr2CaIrO6) was used, which has an unconventional structure that contributes to the reduction of iridium in the catalyst layer. Scanning electron microscopy (SEM) and atomic force microscopy (AFM) showed the reconfiguration of the ionomer in the catalyst layer, resulting in almost full coverage of the catalytic layer with ionomers.
ADVANCED ENERGY MATERIALS
(2023)
Article
Energy & Fuels
Sebastian Prass, Leon Nerlich, Rajveer Singh, Andres O. Godoy, Jasna Jankovic, K. Andreas Friedrich, Nada Zamel
Summary: A silicon oxide thin film is coated on platinum on graphitized low surface area carbon (Pt/C) to enhance the tolerance of proton exchange membrane fuel cells towards carbon monoxide and hydrogen sulfide contamination. The SiO2 coating improves the performance of SiO2-Pt/C when operated with pure hydrogen fuel, but performs worse than Pt/C when operated with CO-contaminated fuel. The SiO2 coating extends the lifetime of SiO2-Pt/C when operated with H2S in the fuel.
Article
Biochemistry & Molecular Biology
Ziqi Xu, Sofia Delgado, Vladimir Atanasov, Tobias Morawietz, Aldo Saul Gago, Kaspar Andreas Friedrich
Summary: Researchers have developed a new type of anion exchange membrane (SEBS-Py2O6) that exhibits high conductivity and shows promise for applications in water electrolysis. When combined with platinum-group-metal-free electrodes in an AWE water electrolysis cell, this membrane achieves a current density of 520 mA/cm^2 at 2 V. These findings demonstrate the potential of SEBS-Py2O6 membranes for efficient water electrolysis.
Article
Nanoscience & Nanotechnology
Joachim Haecker, Tobias Morawietz, Pia Lange, Zhirong Zhao-Karger, Tobias Morawietz, Indro Biswas, Norbert Wagner, Maryam Nojabaee, K. Andreas Friedrich
Summary: Magnesium-sulfur batteries have gained attention as potential post-lithium battery systems due to their high energy density, abundance of raw materials, and low cost. However, their cycling stability is still a challenge. This study demonstrates that the protection of the anode surface with an artificial solid electrolyte interphase (SEI) through an organic coating approach can effectively improve the electrochemical performance of magnesium-sulfur batteries. The coating reduces polarization overpotentials and inhibits the loss of sulfur, resulting in enhanced cycling efficiency and higher discharge capacity.
ACS APPLIED MATERIALS & INTERFACES
(2023)
Article
Electrochemistry
Jakub K. Wlodarczyk, Norman Baltes, K. Andreas Friedrich, Jurgen O. Schumacher
Summary: Modelling and simulation are powerful tools for developing new flow cells like electrolysers and flow batteries. However, the non-ideal behavior of highly concentrated electrolytes poses challenges in conventional parameterization. This study focuses on investigating mass transport of electroactive species in highly-concentrated media, specifically studying hydrogen-bromine flow battery electrolyte using chronoamperometric techniques. The results show successful simulation of current densities using advanced mass transport theory, highlighting the importance of proper electrolyte characterization in establishing predictive models for electrochemical devices.
ELECTROCHIMICA ACTA
(2023)
Article
Electrochemistry
Christina Schmitt, Martina Gerle, Dennis Kopljar, K. Andreas Friedrich
Summary: Extensive parametrization is necessary for physicochemical modelling of lithium ion batteries. This study investigates two cells optimized for high power and high energy applications. The active material type, microstructure, conductivity, and mass loading of the electrodes are determined through various measurements. Laboratory cells are built from the extracted materials to evaluate tortuosity and exchange current density. The differences and similarities of parameters for both cell types are discussed and compared to literature, and then used for the parameterization of a P2D model.
JOURNAL OF THE ELECTROCHEMICAL SOCIETY
(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)