Direct methanol fuel cell (DMFC) powered vehicles are foreseen as the choice of the future. However, the development of DMFC has been hampered by several technical challenges such as anode poisoning and permeation of methanol through the polymer electrolyte membrane into the cathode compartment. Approximately 100-150 mV loss in cell voltage can be attributed to the presence of methanol in the cathode compartment; part of the loss is attributable to the mixed potential phenomenon, and part to the inactivation of the cathode catalyst. Therefore, it is desirable to develop a membrane electrolyte that will prevent or minimize the permeation of methanol. This proposal addresses certain approaches toward minimizing methanol permeation through membrane modifications. A compounded or laminated membrane that will exhibit reduced methanol permeability, while maintaining facile proton transport will be developed using a combination of certain inert polymeric materials and perfluorosulfonic acid polymers. Membranes found to have adequate ionic conductivity and reduced methanol permeability will be tested in a PEM fuel cell with methanol as the fuel.
