High performance and long durability have been the continuous pursuit of proton exchange membrane fuel cells (PEMFCs). Performance and durability are related to the PEMFC distributional uniformity of internal state, which are deeply influenced by the flow channel structures and operating conditions. Therefore, this study proposes a fine-scale flow channel (FSFC) with gradually decreasing flow channel widths (wch) based on parallel flow field. Following, fixing wch at 0.3 mm, the effects of different rib width (wrib), cathode humidity (RHc), stoichiometric ratio (ξc) and coolant mass flow rate (mcool) are studied. Simulation results indicate that FSFC can significantly enhance the various properties of fuel cells, especially the performance and uniformity. Reducing the wrib can enhance the performance and reduce the pressure drop. The appropriate RH and ξc can improve the performance and uniformity while avoiding flooding and purging effects. Similarly, mcool should be kept in the appropriate range to avoid unnecessary pump power loss. This study aims to develop the flow fields in a more fined direction, offering solutions that strike a balance between durability and power density for PEMFC optimization.
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