Advanced Membrane for Direct Methanol Fuel Cells

Development of a low-cost high-exclusion proton-exchange membrane (PEN) for use as an electrolyte in a liquid feed direct methanol fuel cell (LFDMFC) is proposed. The LFDMFC, because of its simplicity (no reformer, simple heat management) and inherent reliability (cell membrane flooded with water), is a potentially attractive power source for low- to medium-power applications, such as a battery replacement for mobile electric power applications. One drawback to LFDMFCs is that methanol permeates across currently available PEMs from the anode to the cathode where it reacts with air (02), resulting in parasitic methanol loss and reduced fuel cell voltage. To overcome this problem, Giner, Inc. proposes to develop a composite membrane which is expected to minimize methanol permeability while maintaining high proton transport, leading to increased LFDMFC power output and improved system efficiency. The research objectives are to incorporate a methanol exclusion layer within a membrane, evaluate physical/chemical properties of the composite membrane, identify conditions to bond electrodes to the membrane, evaluate the membranes in a LFDMFC, and conduct a cost analysis. We expect to develop an advanced PEM for use in a LFDMFC which results in a significant decrease in methanol crossover, compared to Nafion 117, while providing high LFDMFC performance. BENEFITS: LFDMFC-powered vehicles have a very large market potential in states mandating use of zero-emission vehicles by early in the next decade. Additional opportunities include airport and mail vehicles, golf carts, lawn mowers, power tools and dispersed power generators. Military applications include standard vehicles, unmanned underwater and air vehicles, and person portable backpack power supplies.