The nickel–cadmium (Ni–Cd) battery consists of an anode made from a mixture of cadmium and iron, a nickel-hydroxide (Ni (OH) 2) cathode, and an alkaline electrolyte of aqueous KOH. Ni–Cd batteries have an operating voltage of 1.2 V and are used in digital cameras, laptops, calculators, medical devices, space applications, etc. [ 1 ].