The Bipolar Plate (BPP) is a central component of the stack, as it separates the single cells hydraulically, but conducts electrons from one electrolyte compartment to the other. The BPP is therefore found twice within one single-cell-configuration. This study aims to identify the optimal commercially available BPP product for application in rather small (e.g. 2 kW) stacks, balancing performance and cost-effectiveness.
18 different BPP products were tested against the calendered benchmark. Electrical conductivity measurements included material and contact resistance to graphite felts, tested under varying surface pressures. Initial resistance dropped rapidly with increased pressure, stabilizing once contact resistance became negligible, allowing for material resistance determination.