Studies with porous zinc electrodes with additives for secondary alkaline batteries

The effect of the presence of additives Like ZnO, V2O5, PbO and (NH4)(2)CS in solution phase on the performance of solid zinc electrode has already been reported. Small additions of HgO, Sb2O3, TiO2 and Pb3O4 to the pasted zinc electrodes have been evaluated using Cyclic Voltammetry, Potentiodynamic Polarization (with temperature effect), A.C. Impedance measurements, Solution Analysis, and Porosity measurements. Though the additives HgO and Sb2O3 are known for their high hydrogen overpotential, HgO additive has the beneficial effect of imparting minimum standby corrosion, enhanced ageing behaviour and minimum shape change. As regards the additive TiO2, its behaviour is superior to that of HgO as far as the ageing and high temperature performance are concerned. For Pb3O4, the corrosion behaviour as well as ageing are fairly good. However, this additive imparts a disadvantage of lend getting deposited on the counter electrode which would become a setback from the battery point of view. Details of the study are discussed in this paper. (C) 1998 Elsevier Science S.A. All rights reserved.