Mass transport enhancement in a proton exchange membrane fuel cell

Abstract

The performance of typical forced convection and self air-breathing PEM fuel cell (ABFC) is simulated using the Computational Fuel Cell Dynamics approach. The model is first validated with close agreement with relevant published experimental data. For forced convection fuel cell, a flow structure which delivers the reactant transversely to the MEA using an impinging jet configuration at cathode side is proposed and modeled to examine its effectiveness for enhanced performance, especially at high current densities. A multiple impinging jet design is further suggested as an effective way to achieve flow and species uniformity with results in more uniform catalyst utilization. For ABFC, the effect of geometry factors (e.g. channel length and height), device orientation (horizontal, vertical or an inclined angle), and O2 transfer configuration (channel vs. planar) are investigated. New finding is established for the relationship between dominant mass transport modes with length scale of fuel cell. Based on the simulation results, an optimum design for ABFC is proposed.