Barrel effect in an air-cooled proton exchange membrane fuel cell stack

The performance of a single cell affects the proton exchange membrane fuel cell (PEMFC) stack's overall output performance, and the barrel effect occurs in PEMFC stacks. This research presents strategies to alleviate single cell performance degradation in an air-cooled PEMFC stack. Results show that the poorest cell performance is caused by location-related issues. By embedding a copper plate in the position of cell-1, a hollow chamber replaces the cell-1 flow field. The stack equipped with an embedded copper plate achieved its peak power at 2151.22 W under a current of 40 A, signifying an 8.6 % enhancement in performance compared to the original stack. The incorporation of carbon paper and copper plates contributes to the establishment of a uniform stress distribution within the stack, consequently resulting in enhanced voltage consistency, characterized by a minimal variance value of approximately 0.033. Furthermore, the output performance of cell-1 increased by 0.101 V in the stack with copper plate compared to the original stack under 30 A current loading. By introducing a copper plate, the hollow gas chamber replaces the low pressure-drop cells position, effectively resolving the barrel effect in the PEMFC stack, and alleviating the single-cell degradation problem.