Effect of Internal and Interface Structure of GDL on Liquid Water and Oxygen Transport in PEFC

In order to improve the output performance of PEFC, it is important to increase the oxygen concentration at Pt catalyst surface, so the mass transfer performance of gas diffusion layer (GDL) and micro porous layer (MPL) have to be increased. In this study, the real GDL structure was reconstructed by X-ray CT image of carbon paper GDL with MPL. Two-phase flow analysis in GDL with MPL was carried out. In addition, the oxygen transfer calculation was combined with this model. So the effect of MPL on the liquid water distribution in GDL and the gas diffusion performance in wet condition were examined. Furthermore, considering the overlap layer of GDL and MPL, the overall oxygen transfer from channel to catalyst layer was evaluated, and the optimum condition was examined.