Bipolar Plate Design Assessment: Proton Exchange Membrane Fuel Cell and Water Electrolyzer

Proton exchange membrane fuel cells (PEMFCs) as power generators and proton exchange membrane water electrolyzers (PEMWEs) as hydrogen fuel producers play critical roles in implementing hydrogen energy. The bipolar plates (BPPs) in both PEMFC and PEMWE facilitate the distribution of reactants and products, providing electrical connectivity in a series of singular cells. Although both systems are categorized under the same PEM spectrum, the differing reaction mechanisms require specialized plate properties to achieve optimum performance. This short review analyzes the characteristics of BPPs in both PEMFC and PEMWE, with a focus on the plate material, coating, and flow field. This short review concluded that the polymer composite graphite-based BPPs are the most feasible for PEMFC with no coating needed. PEMWE needs SS316 as a BPP material with a conductive coating to withstand the highly corrosive oxygen evolution reaction at the anode. The serpentine flow field showed dominance in PEMFC stack performance due to even fluid distribution and efficient liquid water drainage. However, its high-pressure drop contributes to greater parasitic power. PEMWEs commonly adopt the parallel flow field for its lower contact resistance and bubble formation for efficient mass transport toward the cathode.