HERMETICALLY SEALED BUTTON TYPE NICKEL/CADMIUM STORAGE BATTERY

摘要

To improve the electrochemical oxygen depletion during fast charging and overcharging in an Ni/Cd button cell (1), at least the lid (8) of the nickel wire fabric reinforcement cage (7) surrounding the negative electrode (6) is provided with a PTFE-bound active carbon coating (12). A highly porous PTFE film (13) additionally laid on the lid (8) gives the active carbon layer (12) an increased hydrophobicity which protects it against electrolyte flooding from the direction of the negative electrode, while an ion-exchange membrane (14) inserted between the electrode and the active carbon layer prevents migration of dissolved cadmium into the active carbon layer and metallic precipitation inside the latter.