TEMPERATURE LIMITATIONS OF ALKALINE BATTERY ELECTRODES

The study described here is concerned with possible temperature limitations in Ni-Fe and Ni-Zn aqueous alkaline battery systems in the temperature range -20 degree C to 120 degree C. Thermodynamic studies involved the calculation of potential/concentration relationships for concentrated solutions. Kinetic studies have employed potential step and sweep, rotating ring disk and ac impedance methods. The principal temperature limitation of Ni appears to be reduced coulombic efficiency at high temperature as a result of the coevolution of oxygen at a high state of charge. The irreversible component of charging also increases immediately following prolonged discharge of Ni.