Performance comparison between nano-sized and micro-sized spherical nickel hydroxide

Micro-sized spherical and nano-sized nickel hydroxide were synthesized by using co-precipitation and precipitation transform methods respectively to develop Ni-MH battery with high specific capacity and cycle life performance, and their structures, morphology and electrochemical performance were compared by X-ray diffraction, charge discharge and cyclic voltammetry tests. Results show that nano-sized nickel hydroxide has higher electrochemical activity than that of micron-sized spherical nickel hydroxide. But the reversibility, cycle life performance of electrode of micron-sized spherical nickel hydroxide were much better. Results also show that the doping of nano-sized nickel hydroxide into micron-sized spherical nickel hydroxide has better effects compared with that without doping. For example, the discharge capacity is increased by 9.6%, and cycle life performance of electrode is improved a lot by doping with nano-sized nickel hydroxide which mass fraction is 8% in micron-sized spherical nickel hydroxide doped.