Auxiliary Electrode for Charge Control of Sealed Nickel-Cadmium Batteries

摘要

For platinized cloth auxiliary electrodes the quantity of electrolyte is critical; with too little electrolyte the 02 reduction polarization curve is concave upward, with too much it shows a good plateau and voltageOat low currents, but falls off prematurely and sharply. For VCB or WCB Black the optimum amount is about 0.13 plus or minus .01 gram of 30% KOH per square inch. Contamination by CO2 adversely affects performance, but with the optimum quantity of KOH, conversion of 30 equivalent % to carbonate can be tolerated. As O2 reduction electrodes unplatinized cloths are only 1/5 to 1/10 as good as platinized ones. Platinized cloths moistened with 30% KOH catalyze the H2 plus O2 reaction at a moderate rate. Techniques have been worked out for modifying commercial hermetically sealed cells to allow incorporation of cloth auxiliary electrodes. (Author)