Ball-milled Ni-Mn-Zn hydroxide for alkaline secondary battery

In our previous study, Mn-substituted nickel hydroxide (Ni_0.8Mn_0.2(OH)₂) was prepared by a simple ball milling method to reduce the cost of nickel hydroxide for alkaline secondary battery, but compared to the Ni(OH)₂ electrode, the Ni_0.8Mn_0.2(OH)₂ one showed an obvious decrease in its discharge potential. In this paper, Zn and Mn co-substituted nickel hydroxide (Ni_0.8Mn_0.2???x Zn _x (OH)₂, x?=?0–0.075) is prepared by ball milling. The results of the cyclic voltammetry (CV) tests illustrate that the co-reduction of Mn(IV) to Mn(III) and NiOOH is observed on the Ni_0.8Mn_0.2???x Zn _x (OH)₂ electrodes, and it has a lower reduction potential than NiOOH. The co-substitution of Zn can effectively increase the co-reduction potential. The ball-milled Ni_0.8Mn_0.15Zn_0.05(OH)₂ electrode has a similar capacity (about 270 mAh g^?1 at a 0.2C rate) and cycling durability to the commercial Ni(OH)₂ with ball milling treatment, but the former has better high-power performance.