High-performance polybenzoxazine based composites PEMFC bipolar plates with a multi-layer structure for surface enrichment of conductive phase

Abstract

In this study, a multilayer high-performance polybenzoxazine/expanded graphite composite bipolar plate with a ‘graphite-composites-graphite’ structure was prepared by compressing molding. The surface graphite layer and the conductive network were constructed by hot compressing of graphite paper and the polybenzoxazine/expanded graphite composites. The results show that the multilayer synergy makes composite BP reach an in-plane conductivity of 278.85 S cm−1, an area specific resistance of 9.70 mΩ cm2 and a flexural strength of 75.75 MPa. The ‘graphite-composites-graphite’ structure can make the power density of a single cell assembled by the multilayer composite BP increase by 111.02% and 113.80%. In conclusion, the multilayer bipolar plate with a ‘graphite-composites-graphite’ structure is a promising polymer composite bipolar plate for the proton exchange membrane fuel cell (PEMFC).