3. Metal-air batteries

3.1 General

Metal/air generators consist of metal anodes (negative pole) and oxygen cathodes (positive pole); the oxygen source is generally ambient air. These systems are either fuel cells, primary cells or, more rarely, batteries.

• These systems can be likened to a particular class of fuel cell, since the oxidizing element, oxygen from the air, which reacts at the cathode, is supplied continuously. Similarly, the metal-air cell requires peripheral elements for fluid circulation (air or electrolyte). Furthermore, we must not lose sight of the fact that the efficiency of these systems is very rarely greater than 0.7 (except for very low power ratings), and that electricity production is always accompanied by a high level of heat generation,...