Dynamic reconstruction of Ni-Zn alloy solid-electrolyte interface for highly stable Zn anode
Qian Zhang, Yuhang Dai, Kangning Zhao, Chengyi Zhang, Ruihu Lu, Jinghao Li, Shuhan Jin, Lei Zhang, Qinyou An, Liqiang Mai
Abstract
Aqueous zinc ion batteries (AZIBs) are ideal candidates for large-scale battery storage, with a high theoretical specific capacity, ecological friendliness, and extremely low cost but are strongly hindered by zinc dendrite growth. Herein, Ni−Zn alloy is artificially constructed as a solid-electrolyte interface (SEI) for Zn anodes by electrodeposition and annealing. The Ni−Zn alloy layer acts as a dynamic shield at the electrode/electrolyte interface. Interestingly, the zinc atoms migrate out of the electrode body during zinc stripping while merging into the electrode body during the plating. In this way, the Ni−Zn alloy is able to guide the zinc deposition in the horizontal direction, thereby suppressing the formation of dendrite. Benefiting from those, the Ni−Zn alloy symmetric cell shows a greatly improved cycle life and is able to operate stably for 1,900 h at a current density of 0.5 mA·cm−2. The present study is a strategy for negative electrode protection of AZIBs.