Effect of Temperature and Discharge Rate on Electrochemical Performance of Fiber Nickel–Cadmium Cell

The effect of temperature and discharge rate on the discharge capacity of nickel–cadmium (Ni‒Cd) cell is investigated quantitatively. Ni–Cd cell of 15 A h capacity with nickelic hydroxide as cathode and cadmium as anode was used as test system. Discharge capacity of cell and power at different rates of discharge are two major parameters which define the performance of Ni–Cd cell. The effect of 4 current rates (C/5, C/2, 1 C, and 2 C) at 5 different temperatures (–20, 0, 20, 40, and 60°C) were studied to investigate the discharge performance of Ni–Cd cell. Higher discharge rates affect actual cell capacity because of the increasing difficulties inherent in electrolyte mass transport and electrode reactions as the current density is increased. The internal resistance increases due to drop in the conductivities of the electrolyte and other components at the lower temperatures. Ambient temperatures significantly below 20°C have a depressing effect on the average discharge voltage.