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 m Omega cm(2) and a plate thickness of less than 2 rum 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. (c) 2005 Elsevier B.V. All rights reserved.