Method for producing highly conductive sheet molding compound, fuel cell flow field plate, and bipolar plate

摘要

This invention provides a method of producing a highly electrically conductive sheet molding compound (SMC) composition and a fuel cell flow field plate or bipolar plate made from such a composition. The plate exhibits a conductivity typically greater than 100 S/cm and more typically greater than 200 S/cm. In one preferred embodiment, the method comprises: (a) providing a continuous sheet of a substrate material (bottom sheet) and a continuous sheet of flexible graphite (top sheet) from respective rollers; (b) feeding a resin mixture (comprising a thermoset resin and a conductive filler) to a space between the top sheet and the bottom sheet in such a way that the resin mixture forms a uniform core layer sandwiched between the two sheets to obtain a laminated structure; (c) compressing the laminated structure to obtain a SMC composition having two opposite outer surfaces; and (e) impressing a fluid flow channel to either or both of the outer surfaces (e.g., via embossing or matched-die molding) and curing the thermoset resin to obtain the plate.