Asymmetric wave flow field for enhanced mass transfer in high-power-density PEM fuel cells with metal bipolar plates

Abstract

The development of proton exchange membrane fuel cell (PEMFC) technology has led to increased attention being paid to high-power-density stacks based on metal bipolar plates. In the present study, a novel asymmetric wave flow channel was proposed and investigated through a multiphysics simulation, with the aim of improving output performance and mass transfer behavior. The electrochemical, mass-transfer, and distribution properties of the gas channels in several configurations were compared and quantitatively evaluated. The results showed that the PEMFC with an asymmetric wave channel demonstrated superior performance, and the maximum net output power and temperature distribution uniformity were improved by 11.90% and 16.61%, respectively, compared to the basic straight channel. Subsequently, the curve phase, number of wave cycles, blockage occupancy ratio, and amplitudes of the blockages and grooves were individually analyzed. The performance of PEMFCs with asymmetric wave channels can be enhanced by adjusting the curve phase, increasing the number of cycles, increasing the blockage occupancy ratio, and arranging the amplitudes of the blockages and grooves within a reasonable range. Through structural optimization, the oxygen convection flux, and temperature uniformity of the PEMFC increased by 29.74%, and 10.95%, respectively. These findings provide theoretical support for the structural optimization and formation of metal bipolar plates.