Proton Exchange Membrane Fuel Cells

Proton exchange membrane fuel cells operating on hydrogen/air are being considered as high efficiency, low pollution power generators for stationary and transportation applications. There have been many successful demonstrations of this technology in recent years. However, to penetrate these markets the cost of the fuel cell stack must be reduced. This report details the progress made on reductions in the stack cost by lowered platinum catalyst loadings in the latest stack designs, the development of lower cost membrane electrolytes, the design of alternative bipolar flow field plates, and the introduction of mass production technology. Despite such advances, there is still a need for further reductions in the stack cost, through improvements in the performance of the membrane electrode assembly. However, improved stack performance must be demonstrated not only with pure hydrogen fuel but also, more particularly, with reformate fuel, where tolerance to poisoning by carbon monoxide and carbon dioxide needs to be improved. Advances that are required in the ancillary sub-systems are also briefly considered here.