Formation mechanism of porous alkaline iron electrodes

The formation mechanism of alkaline iron electrodes has been studied using galvanostatic polarisation techniques. An increase in electrode capacity is observed during initial charge-discharge cycling and is attributed to changes in the electrical conductivity, texture, and porosity of the active material. This is supported by an analysis of charge/discharge behaviour and also by linear and Tafel polarisation studies at various stages of formation. Results show that sulphide incorporation enhances the electrical conductivity and thereby exerts a beneficial effect on the charge-discharge characteristics.