Electrochimica Acta, Vol.46, No.17, 2693-2697, 2001
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 electrode material have attracted much attention for their cleanliness and high-energy density. In order to improve the performance of a negative electrode, electrochemical hydrogen electrode reaction on the surface and hydrogen diffusion 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 pretreatment 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.
Keywords:hydrogen storage alloy;rate capability;nickel-hydride batteries;modification with reducing agent;initial activation