Properties of carbon fiber reinforced phenol formaldehyde resin/graphite conductive composite bipolar plate

With carbon fiber, graphite and PF resin powders as raw materials, a type of composite for polymer electrolyte membrane fuel cell was obtained by hot-pressure molding. The effects of carbon fiber's processing modes, content and length on conductivity and flexural strength and interface bonding were investigated. The results showed that the carbon fiber treated by liquid phase oxidation for 10 hours could bring functional group (such as hydroxyl and carboxyl), and improve interface bonding of materials, then improve the properties of the composite; the conductivity and bending strengths would increase firstly and then decrease with the increasing of carbon fiber content. Carbon fiber content would decrease with the increasing of carbon fiber length when properties of the composite at optimal value; the optimal electrical conductivity and flexural strength of composite were 175.4 S/cm, 63.6 MPa, when R/C composite is reinforced by carbon fiber(3%, 10-15 mm) treated by liquid phase oxidation for 10 hours.