Studies of the performance of nanostructural multiphase nickel hydroxide

The nanostructural multiphase nickel hydroxide, which was with doped at least three modifier elements has been synthesized. Scanning electron microscope (SEM) micrograph showed that the nanostructural multiphase nickel hydroxide was consisted of nanostructural particles. It has been confirmed by X-ray diffraction (XRD) examination that the compound has a mixed structure of α-Ni(OH)2 and β-Ni(OH)2. The tap-density of the nanostructural multiphase nickel hydroxide is 1.7–1.9 g/cm3 and the discharge capacity can reach 375 mAh/g. The electrochemical studies revealed that the compound has much better redox reversibility, a much lower oxidation potential of Ni(II) than the corresponding oxidation state compared with β-Ni(OH)2, and a much higher reduction potential. Since it has much higher tap-density and better electrochemical performance than Al-stabilized α-Ni(OH)2 and usual β-Ni(OH)2, it may be a promising positive active material for alkaline rechargeable batteries.