About the PEM Fuel Cell Process
Hydrogen gas is oxidized within a fuel cell. In the process, the chemical energy stored in the hydrogen gas is converted directly, i.e. without combustion, to electrical energy. This process takes place in the heart of the fuel cell, the Membrane Electrode Assembly (MEA).
The MEA comprises two electrodes (cathode: oxygen side and anode: hydrogen side) and the Proton Exchange Membrane (PEM). The PEM is a special plastic film which is permeable to protons but which presents a barrier to electrons.
Hydrogen gas is split by catalysis into electrons and protons in the fuel cell. Due to the chemical imbalance created, the protons (cations) diffuse through the PEM. The resulting potential difference can be tapped on the electrodes in the form of a no-load voltage. As soon as an electric circuit is connected to the fuel cell, the surplus electrodes flow to the cathode, where they combine with the oxygen and the protons to form water (H 2 O). The water produced escapes via the air vent in the form of water vapor.
• Power Per Cell: 200 mW
• Total Power (5 Cells): 1 W
• Generated Voltage: 0.4 – 0.96 V per cell
• Electrode Area: 4cm² per cell