Impact of optimizing the cathode flow channel on proton exchange membrane fuel cell cold start performance

Abstract To investigate the impact of various cathode flow channels on PEMFC performance, a three‐dimensional, transient, multiphase flow model is developed. The results indicate that three optimized cathode flow channels, namely, a gradually expanding channel, a 3D wave channel, and the combination of expanding progressively and a 3D wave channel, potentially enhance PEMFC's output performance in comparison to a straight flow channel. On this basis, the model above is extended to cold start conditions, and the effects of cathode flow channel optimization on the PEMFC's cold start performance are investigated under ambient temperatures of −20°C, −8°C, and −5°C. The findings indicate that none of the three cathode flow channels that have been tuned can successfully cold‐start a PEMFC at −20°C, but the temperature rise of the gradually expanding channel is higher; at −5°C, PEMFC can be successfully cold‐started using all three optimized cathode flow channels, and the cold‐start performance of 140% gradually expanding channel is best. At −8°C, PEMFC can only be successfully cold started using 140% gradually expanding channel, in which the ice volume fraction decreased by 2.31% compared with the straight channel. PEMFC with a gradually expanding cathode flow channel structure has the best cold start performance.