THE EFFECT OF THE ELECTROLYTE ON THE DEGRADATION PROCESS OF LANI5 ELECTRODES

The effect of the process parameters, such as temperature, charge rate and charge time, rest period, discharge rate, KOH concentration of the electrolyte and encapsulation with copper, upon the hydrogen storage capacity of LaNi5 electrodes was investigated as a function of the number of charge-discharge cycles. The decay in storage capacity of the electrodes was ascribed to a crashing-oxidation process at the surface of the LaNi5 particles. The oxidized layer at the surface of the particles was found to be formed by a reaction with the electrolyte. The growth of this layer could be diminished by encapsulation of the LaNi5 particles by copper without a reduction in the storage capacity of the electrodes. © 1990.