Pre‐Corrosion of Zinc Metal Anodes for Enhanced Stability and Kinetics

Abstract

AbstractNon‐uniform zinc plating/stripping in aqueous zinc‐ion batteries (ZIBs) often leads to dendrites formation and low Coulombic efficiency (CE), limiting their large‐scale application. In this study, a pre‐corroded Zn (PC‐Zn) anode with 3D ridge‐like structure is constructed by a facile solution etching in sodium hypophosphite (NaH2PO2) solution. The surface preparation process can significantly remove impurities from the passivation layer of bare Zn anode, thus exposing a great quantity of active sites for easy plating/stripping. Moreover, the pre‐corroded structure enables a uniform‐distributed electric field to promote the 3D Zn2+ diffusion process and accelerate the transfer kinetics, thereby suppressing the zinc dendrites and interfacial side reactions. Consequently, symmetric cells with PC‐Zn electrodes demonstrate remarkable stability, maintaining cycles for over 3200 h under 1 mA cm−2. The PC‐Zn/VO2 full cell maintains a specific capacity of 361 mAh g−1 at 0.1 A g−1, and a capacity retention rate of ≈80% over 1000 cycles at 4 A g−1. Notably, no obvious dendrites and side reactions are detected after extended cycling. Leveraging the cost‐effectiveness, environmentally friendly nature, and easy fabrication of the PC‐Zn electrode, this Zn protection strategy holds promise for advancing the industrial application of ZIBs.