Abstract:The electroless plating cobalt of nickel hydroxide particles used as a positive active material for rechargeable alkaline batteries and the effects of the cobalt coating content on the nickel electrode performance were investigated. The characteristics of the electrode deposited cobalt, such as discharging capacity, utilization of active material and reversibility of Ni(OH)₂/NiOOH redox reaction were studied by comparing charging/discharging curves and cyclic voltammetric results. The results indicated that the nickel hydroxide electrode deposited cobalt exhibited better charging/discharging cyclic characteristics and excellent electrode performance. The electrochemical impedance data of the nickel hydroxide electrode before and after electroless plating cobalt were obtained. These data indicated that the cobalt coating could decrease the contact resistance between the nickel hydroxide and the substrate, and increase the proton conductivity and electronic conductivity of nickel hydroxide. The mechanism of improving electrode performance by cobalt coating were discussed.

Key words: nickel hydroxide electrode　electroless plating cobalt　electrode performance electrochemical impedance　conductivity