A comprehensive overpotential analysis of high-power density fuel cell: channel/rid width design

Reducing the channel/rib width is a possible approach to improve the performance of fuel cells. However, few experiments were conducted to verify this claim, especially for channel/rib width of below 0.4 mm. In this study, we conducted quantitative analysis to investigate the influence of channel/rib geometries on the performance of fuel cells through experiments and model simulations. As the channel/rib width reduced from 1.0 to 0.2 mm, the fuel cell power density increased by 31% under high humidity condition. The influence of channel/rib width on overpotentials has also been revealed. Notably, narrow channels/ribs can lead to a significant reduction in mass transfer loss under high current density. Three-dimensional simulation results suggest that the reduction of channel/rib width improves the uniformity of gas and water distribution under channels and ribs by 95%. This research provides a concrete foundation for the design of bipolar plates with high-density flow channels for high-power density fuel cells.