Fuel electrode for metal-air/oxygen cell - having second porous layer for disengaging oxygen

摘要

Fuel electrode for a rechargeable cell esp. of the metal air or metal oxygen type or the alkali electrolyte type and having a first porous layer covering it on which the electrochemical reactions are effected during discharge characterised in that a second more finely porous layer is provided on the first layer at the level of which oxygen is released during charging. Opt. a third porous stopping layer contg. very fine pores is provided. The second layer prevents access of the oxygen to the reacting layer during charge, so that the life of the cell is increased. Pref. the first layer is formed of particles of active carbon or catalyst-coated carbon opt. cohered by PTFE.