Plastic-bonded electrodes for nickel—cadmium accumulators. VIII. Study of oxygen recombination rate on plastic-bonded cadmium electrodes provided with active carbon catalyst

Abstract

The oxygen recombination (reduction) rate on plastic-bonded cadmium electrodes in sealed NiCd systems can be controlled by the use of a catalytic mix consisting of active carbon and carbon black either in the pure state or mixed with PTFE. This catalytic mix is either rolled onto the gas side of the plastic-bonded cadmium electrode or added to the active material prior to the preparation of the electrode by a rolling technique. The highest oxygen recombination rate, which surpassed that obtained with commercial pocket-type electrodes, was obtained in both cases by the use of an active carbon, carbon black and PTFE catalytic mix. In this case an optimum three-phase boundary, well known from oxygen electrodes for fuel cells, was established.