Protection of sealed nickel-cadmium cells against cell voltage reversal II. Influence of the separator on the formation of cadmium bridges

After studying three types of polyamide fabric, each with different physical parameters and different properties, as separators in an alkaline electrolyte, two widely differing materials were selected. These were evaluated by scanning electron microscopy both before and after the chemical deposition of cadmium hydroxide (Cd(OH) 2). Their physical parameters were correlated with their efficiency in the formation of protective cadmium bridges in sealed nickel-cadmium accumulators during deep discharge accompanied by voltage reversal. Two types of sealed accumulators were employed with differing electrode geometry and interelectrode distance, which was shown to be related to the Cd(OH) 2 content of the separator.