PEM Fuel Cell Materials: Costs, Performance, and Durability

Abstract

Since the discovery of fuel cells in the nineteenth century, they have been designed for operation with liquid alkaline, acid, and solid oxide ion conducting electrolytes in different temperature ranges to produce electrical power for stationary, portable, and automotive applications. The liquid acid that provides ionic conduction has been replaced by fairly thin proton conducting membranes such as polystyrenes and perfluorosulfonic acids (PFSAs) like Nafion and more recently with hydrocarbon-based polymers. These fuel cells incorporating a proton-conducting membrane rather than liquid electrolyte to separate the anode and cathode (forming a 3-layer sandwich or catalyst coated membrane) are referred to as PEMFCs. PEMFCs are preferred for use in automotives for a multitude of reasons including their high volumetric and gravimetric power density.