Structure and Electrochemical Characters of Nano-sized Ni(OH)_2-C Prepared by Precipitation-transformation Method

Nano-sized Ni(OH)2-C and Ni0.96Co0.04(OH)2-C were synthesized by a precipitationtransformation method. Their physical and electrochemical characteristics, such as crystal configuration, surface area, granule appearance, special capacity, rate discharge capability, electrochemical action reversibility, proton diffusion rate and electrode kinetics were investigated. Ni(OH)2-C and Ni0.96Co0.04(OH)2-C have the crystal structure of a single β(Ⅱ) phase. Their electrochemical characteristics mainly depend on their crystal configuration, crystal grain and conductibility. Adding nano carbon black to Ni(OH)2 can improve its electrochemical performance. Adding spindleshaped nano-carbon black can more effectively advance Ni(OH)2 (Ni(OH)2-C) electrochemical performance then adding flake- shaped one. Adding active carbon is futile. Substituting Ni with Co (Ni0.96Co0.04(OH)2 formed) can upgrade nano-Ni(OH)2 rate discharge ability and electrochemical reversibility. Adding both Co and carbon black can increase Ni(OH)2 discharge capacity.