摘要 |
In rechargeable, electrochemical cells, oxygen may evolve on charge, overcharge or any reversal of polarity. The invention concerns an auxiliary, electrochemical, transfer electrode to catalyze the recombination of such oxygen with the anode mass. The auxiliary electrode may comprise a porous carbon bonded with PTFE, or it may comprise a zinc gel having graphite particles and/or metal-plated zinc particles - where the metal that plates the zinc particles may be copper, or may be any of cobalt, cadmium, nickel, or silver. The auxiliary electrode for rectangular electrodes as used in flat plate or jelly roll cells may have the catalytically active material PTFE bonded to the current collector. The cell is generally one having a zinc anode, a metal oxide cathode (usually manganese dioxide), and an aqueous alkaline electrolyte (usually potassium hydroxide) contacting both anode and cathode. |