ABSTRACT
Sir William Grove is usually credited with inventing the hydrogen fuel cell in 1845 based on earlier observations of Friedrich Schoenbein (first published in 1839).1 This pioneering work by Schoenbein and Grove utilized hydrogen as the fuel and oxygen from air as the oxidizer, and the fuel cells operated close to room temperature. We now know that many different fuels (e.g., hydrogen, hydrazine, methanol, formic acid, and ammonia) and oxidizers (e.g., air, pure oxygen, hydrogen peroxide) may be employed in fuel cells,2 and fuel cells may operate over a broad range of temperatures up to about 1000°C.3 However, this work will focus attention on hydrogen-air fuel cells that operate at temperatures slightly above ambient: so-called proton exchange membrane (PEM) fuel cells.
