Limitations in the use of plastic-bonded electrodes in sealed nickel—cadmium cells and their reasons I. Prismatic and cylindrical cells

Abstract

The use of plastic-bonded (PB) electrodes in prismatic, sealed NiCd cells is limited by the need for a negative electrode layer (active material, plastic binder, activating agents) with the highest possible oxygen recombination rate. Otherwise, a non-uniform charge distribution occurs in the multi-electrode pack during accelerated cycling (the outer PB Cd electrodes differing from the central one). This leads to a decrease in the discharge capacity: evidence that the active material is not fully utilised in the current generating process. With cylindrical sealed cells, the demands imposed on the oxygen recombination rate of PB Cd electrodes are less severe, difficulties, in this case, being due more to the preparation of PB Ni electrodes with a thickness comparable with the negative electrodes (⩽ 1 mm).