Effects of electrical resistance of the gas diffusion layer of a PEM fuel cell

A three-dimensional computational model of polymer electrolyte fuel cell (PEMFC) was employed to investigate the effects of electron transport: through the gas diffusion layer (GDL) and catalyst layer. The electron transport equation was added to our previously established 3D model. Using reasonable electrical conductivities for the GDL and catalyst layer, especially the different values for the in-plane and through-plane conductivities for the GDL, it was found that the effect of the electronic resistance of GDL is not as significant as previous researches suggested. The previously overestimated effect was mainly caused by assuming the GDL's inplane conductivity to be the same as through-plane conductivity, which can have an order of magnitude difference. Comparing the magnitude of ohmic loss from the electron current to that of the proton current, it can also be concluded that the ohmic heating from the electron current is negligible.