Activation mechanism of Ti0.5Zr0.5Ni1.3V0.7Mn0.1Cr0.1 electrode in nickel-hydride batteries

Nickel-hydride batteries using hydrogen storage alloys as a negative electr ode material have attracted much attention for their cleanliness and high-e nergy density. In order to improve the performance of a negative electrode, electrochemical hydrogen electrode reaction on the surface and hydrogen di ffusion in the bulk of alloy should proceed with negligible overvoltage in charging and discharging process. In this study, the discharge capacity and high-rate dischargeability were evaluated as a function of the pretreatmen t of the alloy surface and also molding pressure of the negative electrode. The results were discussed on the basis of the charge transfer reaction on the surface and the hydrogen diffusion behavior in the alloy. (C) 2001 Els evier Science Ltd. All rights reserved.