Experimental investigation of expanded graphite/phenolic resin composite bipolar plate

A series of expanded graphite/phenolic resin composite bipolar plates with different phenolic resin contents have been prepared by resin vacuum impregnation and hot press method. The alcohol-soluble and water-soluble phenolic resins were used as polymer filler and expanded graphite plate are used as substrate carbon plate. The results indicated that the tensile strength, flexural strength, resistivity, gas permeability and corrosion current density of bipolar plate are influenced by resin solution concentration. When the solution concentration of water-soluble phenolic resin is 25%, the bipolar plate exhibits better mechanical property and resistivity. The electrochemical impedance spectroscopy (EIS) result shows that the overall resistance of homemade expanded graphite/phenolic resin composite bipolar plate is lower than that of graphite bipolar plate. The composite bipolar plates should be a promising candidate for PEMFCs and vanadium redox flow battery application.