Polymeric composite bipolar plates for vehicle applications

At present membrane electrode assembly performance levels and stack operating conditions of PEM fuel cells, a plate area specific resistance of less than approximately 20 mΩ cm2 and a plate thickness of less than 2 mm are required to meet the vehicular volumetric power density target (>2 kW l−1). It is, however, difficult to meet these aggressive requirements, and simultaneously obtain good mechanical properties when using polymeric plate materials. Polymers become brittle and break frequently at the high conductive filler loadings (e.g., >50 v/o graphite) required for high conductivity. This study investigates a potential approach for obtaining high plate conductivity at low conductive filler loadings, thus enabling high volumes of thin and ductile plates to be manufactured at low scrap rates.