ZnO@NC/CNT as Anodic Material for Zinc Nickel Secondary Batteries with Ultra-High Stability and Long Cycle Life

Abstract

Zinc-nickel batteries are the ideal alternative to lithium-ion batteries because of their low cost, safety, and high energy density. However, the disreputable problems, such as zinc dendrites and poor electrical conductivity, have seriously hindered its further development. Herein, ZnO@NC/CNT is prepared via a three-step method of the hydrothermal-calcination-water bath. It has the inhibition ability of electrochemical polarization due to the highly conductive carbon nanotube backbone forming an internal conductive network, which increases the electron transfer rate. On the other hand, N atoms with strong pro-zinc ability can effectively homogenize zinc deposition and inhibit dendrites. Consequently, the ZnO@NC/CNT anode still retains the capacity of 570 mAh g −1 after 2150 cycles, with 90% of theoretical capacity (627 mAh g −1 ). This study provides a reference for the design of Zn−Ni electrode materials with a high discharge-specific capacity, high rate performance, and long cycle stability.