Optimization of Electrical Conductivity for Composite Bipolar Plates in PEM Fuel Cell

Composites with high electrical conductivity are favourite candidates to replace the traditional graphite bipolar plate in polymer electrolyte membrane (PEM) fuel cell. Efforts to develop these composites started with the understanding of the mechanism of electrical conduction in them. Melt compounding was adopted mainly in this work for the preparation of composite material formulations which were then compression moulded to obtain plate specimens. Polypropylene‐graphite, PP/G, composites were found to have the disadvantage of relatively low electrical conductivity of only up to 7 S/cm at 80 wt.% G. Combining other conductive fillers such as carbon black (CB) increased conductivity many times. Optimization of the material and processing parameters can lead to PP/G/CB composites which meet the requirement for viable application in PEM fuel cell.