SOME FACTORS AFFECTING THE CYCLE LIVES OF LANI5-BASED ALLOY ELECTRODES OF HYDROGEN BATTERIES

The electrode characteristics, the hydrogen equilibrium properties, the crystallographic and mechanical properties of simple ternary alloys of the type LaNi5-xMx(M ≡ Ni, Mn, Cu, Cr, Al and Co) were examined. The effect of substituting elements to improve the cycle life increased in the order: M ≡ Mn, Ni, Cu, Cr, Al and Co. The lower the capacity, the smaller the volume expansion ratio, the slower the pulverizing rate and the lower the Vickers hardness were, the longer the cycle life became. The alloy LaNi2.5Co2.5, which showed the highest durability as a negative electrode, satisfied all these requirements. © 1990.