1. PEMFC fuel cells

1.1 Operating principle of a PEM fuel cell

The PEMFC (Proton Exchange Membrane Fuel Cell) converts the chemical energy of dihydrogen oxidation into electrical and thermal energy, according to the overall water synthesis reaction. The fuel cell consists of two electrodes, one supplied with dihydrogen (referred to as hydrogen in the following) and the other with dioxygen (or air), separated by a proton exchange membrane (the electrolyte). On the anode side, hydrogen is oxidized to protons at the surface of a catalyst, with the release of electrons according to the following half-equation :