NSF Award
9961062
A new conductive composite material is proposed for use in fuel cells as a bipolar plate between adjoining cells in series. The new composite material is lightweight and promises to reduce manufacturing time and costs associated with incorporating complex field flow channels into the plate surface. The conductive material consists of polybutylene terephthalate thermoplastic embedded with carbon nanotubes, which are 10x100 Angstroms in size. The material will be processed to reduce pellets to a powder for compression molding, extrusion and injection molding trials. Processing and manufacturing methods for the composite will be optimized to produce thin plates for testing. The effects of incorporating plasticizers and coupling agents on the material processing will be investigated. Physical and mechanical properties of the molded composite will be determined including gas permeability, tensile and flexural strength, thermal expansion coefficient, resistivity and contact resistance against other cell components. The plates will be tested in a proton exchange membrane fuel cell (PEMFC) and the electrochemical performance compared with cells containing plates made of graphite and other composites. The effects of service use at 80oC will be assessed by re-establishing the physical and mechanical characteristics after continuous cell operation.
