Numerical and experimental investigation of baffle plate arrangement on proton exchange membrane fuel cell performance

Reactant distribution and water management are critically important to the performance of proton exchange membrane fuel cell (PEMFC). The application of baffle plate is an effective way to improve reactant transport and water removal in the porous electrode of PEMFC. In this study, a three-dimensional multiphase PEMFC model is developed with Forchheimer's inertial effect in the porous electrode to better simulate the convective flow induced by the baffle plate, which is validated experimentally. Three kinds of flow field design including the conventional parallel flow field, parallel trapezoid baffle plate (PTBP) and staggered trapezoid baffle plate (STBP) flow fields are investigated both numerically and experimentally, on the PEMFC mass transport characteristics and performance. It is found that both the PTBP and STBP flow fields form the over-block-convection around the baffle plate which is beneficial to mass transfer from channel to electrode. The STBP flow field further forms the over-rib-convection (or cross flow) induced by a stable pressure gradient between the adjacent flow channels. The cross flow stem from the STBP arrangement further improves the uniformity of reactant distribution and removes the excess liquid water in the porous electrode, and hence enhances the PEMFC performance in a large range of operating conditions.