An Improvement On Redox Reversibility Of Cobalt Oxyhydroxide In Nickel Hydroxide Electrodes

摘要

In this paper, two kinds of cobalt oxyhydroxide conductive networks were introduced into nickel hydroxide electrodes by different methods—electrochemically-oxidized (EO) or chemically oxidized (CO) CoOOH on the surface of nickel hydroxide particles. The redox behaviors of them were studied by using cyclic voltam-metry (CV) and X-ray diffraction (XRD) measurements. It shows that because CoOOH(CO) has better redox reversibility than CoOOH(EO), the structure of the former can be kept when nickel hydroxide electrodes are subjected to a negative potential. Thus, 98.5% capacity retention is demonstrated on nickel/metal-hydride (Ni-MH) batteries with CoOOH(CO) after being imposed over-discharge state storage; on the contrary, only 81.4% capacity retention is found on the batteries with CoOOH(EO).