Impact of Thickness of Polymer Electrolyte Membrane and Gas Diffusion Layer on Temperature Distributions in Polymer Electrolyte Fuel Cell Operated at Temperature around 90 °C

Polymer Electrolyte Fuel Cell (PEFC) is desired to be operated at temperature around 90 °C for stationary applications during the period from 2020 to 2025 in Japan. It can be expected thinner polymer electrolyte membrane (PEM) and gas diffusion layer (GDL) would promote the power generation performance of PEFC at this temperature. The aim of this study is to understand the impact of thickness of PEM and GDL on the temperature profile of interface between PEM and catalyst layer at the cathode (i.e., the reaction surface) in a single PEFC with an initial operation temperature (T_ini). An 1D multi-plate heat transfer model based on temperature data of separator measured using thermograph in power generation process was developed to evaluate temperature of the reaction surface (T_react). This study investigated the effect of T_ini, flow rate and relative humidity of supply gas on T_react distribution. The study finds that when using thin GDL, the even distribution of T_react – T_ini is obtained irrespective of thickness of PEM, T_ini and relative humidity conditions. T_react – T_ini using Nafion 115 is higher than the other thin PEMs irrespective of T_ini and relative humidity conditions. It can be concluded that the even temperature distribution could be achieved by using thin PEM and GDL.