The dissolution of iron from the negative material in pocket plate nickel-cadmium batteries

A common mode of failure of nickel-cadmium flooded pocket plate cells is iron poisoning of the positive plate due to transfer of iron into the active material from active materials and materials of construction. Nickel plated steel pockets are sometimes used to minimize iron dissolution, particularly on the positive electrode. Sometimes alpha -Fe sub(2)O sub(3) is used as an additive to the cadmium electrode. This paper assesses the extent of dissolution of iron from alpha -Fe sub(2)O sub(3) by using electron microscopy, X-ray crystallography, cyclic voltammetry, coulometric and atomic absorption measurements.