Electrochemical properties of Co(OH)2 powders as an anode in an alkaline battery.

The structure and electrochemical properties of β-Co(OH)2 powders, synthesized by a chemical precipitation method, were investigated. The results of X-ray diffraction show that a reversible reaction between β-Co(OH)2 and hcp Co occurs. The cycling induces a capacity loss of β-Co(OH)2 electrode, which is probably attributed to the dissolution of β-Co(OH)2 and the subsequent formation of α-Co(OH)2 and CoOOH. The results of electrochemical impedance spectra indicate that the electrochemical discharge process of the as-prepared Co(OH)2 powders consists of three steps, namely the charge-transfer reactions of Co/CoH x and Co/Co(OH)2, and the hydrogen diffusion within Co, depending on the depth of discharge. [ABSTRACT FROM AUTHOR]