Formability improvement in multi-stage stamping of ultra-thin metallic bipolar plate for proton exchange membrane fuel cell

Multi-stage stamping process is the promising technology to fabricate the metallic bipolar plate (BPP) for proton exchange membrane (PEM) fuel cell. In the present study, a novel die design in the pre-forming stage is proposed and its effect on the formability of ultra-thin metallic BPP is verified by the finite element (FE) simulations of micro- and macro-scale BPP channels. It reveals that the multi-stage forming with the proposed die approach significantly improve the formability of ultra-thin BPP. As a result, the more uniform thickness distribution and considerable reduction of springback are beneficial to the fabrication of high quality metallic BPP. Furthermore, the relatively high reaction efficiency (∼79.4%) of fuel cell stacks can be predicted, indicating the high fuel consumption. These findings demonstrate the feasibility and efficiency of the proposed die design in the fabrication of ultra-thin metallic BPP based on the perspectives of both the formability and energy efficiency.