Article
Chemistry, Physical
Fatih Daricik, Alparslan Topcu, Kadir Aydin, Selahattin Celik
Summary: In this study, carbon fiber/epoxy composite laminates were modified with multi-walled carbon nanotube superconductor materials to improve their electrical and mechanical properties for wider application as bipolar plates in PEMFC systems.
INTERNATIONAL JOURNAL OF HYDROGEN ENERGY
(2023)
Article
Chemistry, Physical
Fabrizio Roncaglia, Marcello Romagnoli, Simone Incudini, Elena Santini, Manuel Imperato, Luca Spinelli, Alessandro di Bona, Roberto Biagi, Adele Mucci
Summary: This study presents an experimental method for preparing graphite-epoxy composites suitable for manufacturing bipolar plates in Proton Exchange Membrane Fuel Cells. Wet mixing was found to be advantageous in achieving good electrical and mechanical properties, with the addition of a small percentage of carbon black as a secondary filler. Modeling the effects of molding parameters on a fixed-composition graphite-epoxy composite provided valuable information for future improvements, resulting in conductivity values exceeding US DOE requirements.
INTERNATIONAL JOURNAL OF HYDROGEN ENERGY
(2021)
Article
Energy & Fuels
Pouya Barnoon, Davood Toghraie, Babak Mehmandoust, Mohammad Ali Fazilati, S. Ali Eftekhari
Summary: This study examined cooling, stress, and displacement of bipolar plates of Proton Exchange Membrane Fuel Cells under different ambient conditions, and carried out multi-objective optimization to determine the best thickness and number of plates. Findings showed that increasing the number and thickness of bipolar plates can reduce temperature, with forced cooling reducing temperature by over 30 K, and natural cooling increasing temperature faster but potentially causing hazards to the system.
Article
Green & Sustainable Science & Technology
Peng Ren, Pucheng Pei, Dongfang Chen, Lu Zhang, Yuehua Li, Xin Song, Mingkai Wang, He Wang
Summary: Metallic bipolar plates (BPs) in fuel cells experience corrosion and surface destruction under automotive operating conditions, with dynamic load and startup-shutdown being the main accelerators. Dynamic potential accelerates the breakdown of passivation layer, while pits rich in Cr-species provide protection. Startup-shutdown drives complex corrosion and passivation stages, leading to global destruction represented by microstructure and pits, while producing a surface film through secondary passivation.
Article
Chemistry, Physical
Minh Tien Tran, Dae Ho Lee, Ho Won Lee, Dong-Kyu Kim
Summary: In this study, a novel die design is proposed for the fabrication of ultra-thin metallic bipolar plates (BPP) for proton exchange membrane (PEM) fuel cells. Finite element simulations demonstrate that the multi-stage forming with the proposed die approach significantly improves the formability of ultra-thin BPP. The results indicate a more uniform thickness distribution and reduced springback, leading to the fabrication of high-quality metallic BPP and a relatively high fuel consumption efficiency.
INTERNATIONAL JOURNAL OF HYDROGEN ENERGY
(2022)
Article
Chemistry, Physical
Fabrizio Roncaglia, Adele Mucci, Marcello Romagnoli, Luca Spinelli, Alessandro di Bona, Roberto Biagi
Summary: To sustain the Hydrogen Economy, proton exchange membrane (PEM) devices are crucial for the generation and utilization of clean hydrogen. This study focuses on the technical improvement and cost reduction of bipolar plates, an essential part of PEM devices, by using cheap and commercially available graphite-epoxy composites. By adjusting the formulation and processing conditions, materials with desired electrical conductivity and gas permeability were successfully achieved. The processability and productivity of the method were improved, and the effect of molding pressure on the properties of the samples was analyzed.
INTERNATIONAL JOURNAL OF HYDROGEN ENERGY
(2023)
Article
Energy & Fuels
Timon Novalin, Bjorn Eriksson, Sebastian Proch, Ulf Bexell, Claire Moffatt, Jorgen Westlinder, Carina Lagergren, Goran Lindbergh, Rakel Wreland Lindstrom
Summary: The use of stainless steel as bipolar plates in proton exchange membrane fuel cells (PEMFCs) has been a concern due to the risk of corrosion and metal ion contamination. Previous studies on this hazard have relied on ex-situ corrosion assessments which may not accurately represent real operating conditions. In this study, uncoated stainless steel bipolar plates were subjected to in-situ hybrid endurance/stress testing to simulate realistic conditions and re-evaluate the need for additional corrosion protection. The results showed no signs of surface dissolution and negligible trace metal concentration in the membrane electrode assembly (MEA). Contact resistance values were stable and changes in cell performance and voltage degradation were unrelated to the presence of uncoated bipolar plates. The corrosion resistance of uncoated stainless steel plates in PEMFCs was attributed to decoupling of bipolar plate surface potentials from electrode potentials and operational control to sustain stainless steel surface passivation.
Article
Chemistry, Physical
Tunahan Gunduz, Tolga Demircan
Summary: A numerical analysis was conducted to investigate the effects of current collector plate geometry on the performance of a cylindrical PEM fuel cell. The results showed that using helix flow channels in the current collector plate geometry can increase the flow density and current density of the fuel cell, and the power density also increases with the operating pressure.
INTERNATIONAL JOURNAL OF HYDROGEN ENERGY
(2022)
Article
Thermodynamics
Huawei Chang, Fengyang Cai, Xianxian Yu, Chen Duan, Siew Hwa Chan, Zhengkai Tu
Summary: This research has significant implications for the reliable thermal management of proton exchange membrane fuel cells. By using micro-thermocouples for temperature distribution measurement in an air-cooled fuel cell stack, the effects of hydrogen pressure and airflow rate were analyzed.
Article
Thermodynamics
Tabbi Wilberforce, A. G. Olabi, Daniel Pritchard, Mohammad Ali Abdelkareem, Enas Taha Sayed
Summary: The advancement in bipolar plate technology can enhance the performance of hydrogen fuel cells, making them more suitable for renewable energy systems. Two new bipolar plate designs were developed and compared with a reference channel. The rectangular and hexagonal baffle designs outperformed the reference channel, with the rectangular design showing the best performance.
Article
Chemistry, Physical
Qilong Huang, Yizhang Tong, Bin Hu, Jingshu Huang, Xianwu Cao, Zhitao Yang, Guangjian He
Summary: In this study, a multilayer high-performance polybenzoxazine/expanded graphite composite bipolar plate with a 'graphite-composites-graphite' structure was prepared. The results showed that the multilayer synergy improved the conductivity and flexural strength of the composite bipolar plate, leading to an increased power density of the assembled cell.
INTERNATIONAL JOURNAL OF HYDROGEN ENERGY
(2023)
Article
Energy & Fuels
Tabbi Wilberforce, Oluwatosin Ijaodola, Ahmad Baroutaji, Emmanuel Ogungbemi, Abdul Ghani Olabi
Summary: This study explores ideal materials for the manufacturing of flow plates in fuel cells and compares the performance of two flow field channels using different bipolar plate materials. The results show that metal foam flow channels outperform serpentine flow channels, and aluminum material performs better than copper and stainless steel materials.
Article
Energy & Fuels
Chien-Ju Hung, Wei-Jen Chen, Chao-An Lin, Huan-Ruei Shiu, Bin-Hao Chen
Summary: This study examines the effects of compression, deformation, and contact area in the membrane electrode assembly (MEA) and considers the electrical impedance of fuel cell stacks due to the assembly of metallic bipolar plates. It suggests that an increase in compression force can improve contact resistance, but excessive compression may lead to extra contact resistance and damage to the MEA structure. By proposing different fillet radii metallic bipolar plates, the study found that an appropriate fillet radius can reduce contact resistance by 13% and prevent the accumulation of compression, thus maintaining contact resistance at adequate levels. The current design offers a simple and effective method to minimize dimension tolerance of single fuel cell units and support sufficient compression.
Article
Chemistry, Physical
Xiejing Luo, Luqi Chang, Chenhao Ren, Jiuhong Zhang, Dawei Zhang, Jizheng Yao, Jie Song, Zhanfeng Deng, Chaofang Dong, Xiaogang Li
Summary: This study proposes a sandwich-like C/(Ti:C)/Ti modified Ti bipolar plates, and through computational simulations and experimental verification, it demonstrates that the bipolar plates have lower interfacial contact resistance and smaller corrosion current density, making them suitable for various operating conditions.
JOURNAL OF POWER SOURCES
(2023)
Article
Engineering, Industrial
A. Vasilyev, J. Andrews, S. J. Dunnett, L. M. Jackson
Summary: This paper develops a novel model for dynamic reliability analysis of a polymer electrolyte membrane fuel cell system to consider multi-state dynamics and ageing. By combining physical and stochastic sub-models, the study investigates the effects of operating conditions on system reliability. Monte Carlo simulations demonstrate the significant influence of purging and load cycles on the longevity of the fuel cell system.
RELIABILITY ENGINEERING & SYSTEM SAFETY
(2021)
