A capillary extended channel model of PEM fuel cells

Water flooding in porous electrodes and gas channels is the main issue hampering the performance of Proton Exchange Membrane (PEM) fuel cells. Since most traditional numerical models are based on "Mist-flow" assumption, which will greatly underestimate the liquid saturation within the cell, it is of vital importance to develop a model accounting for liquid evolution in gas channels. In light of that, we propose a capillary extended channel model and carry out a series of simulations focusing on heat and mass transport within the cell under low gas velocities. It can be drawn from the results that this model can not only overcome the setback of underestimation in liquid saturation of traditional models, but also can account for the effects of different wettability of channel walls.