Effect of varying rib area portions on the performance of PEM fuel cells: Insights into design and optimization

The optimization of proton exchange membrane (PEM) fuel cells via bipolar plate (BPP) design is critical, yet the impact of BPP/channel redesign on electric resistance and cell output has been less explored. This study uses multi-physics models to analyze how PEM fuel cell performance is influenced by rib area portion variations (20%–70%). The potential gradient is determined to be the primary driver for charge conduction, and the benefits of optimized charge transport for enhancing cell outputs are established. An intricate interplay between rib area portion, electron transport efficiency, and cell resistance is uncovered. It is demonstrated that larger rib area portions, while promoting electron transport, inadvertently increase interfacial and overall cell resistance, compromising performance. The study also emphasizes the necessity for a more nuanced consideration of oxygen over hydrogen, given the implications on cell resistance and gas flux. Rib area portions of 20% and 30% are identified as achieving superior performance by 24.3%, offering an optimal design strategy. Crucial insights for improving PEM fuel cell performance through BPP design are provided in this study.