Long Shelf‐Life Efficient Electrolytes Based on Trace <scp>l</scp>‐Cysteine Additives toward Stable Zinc Metal Anodes
Cong Huang, Xin Zhao, Yisu Hao, Yujie Yang, Yang Qian, Ge Chang, Yan Zhang, Qunli Tang, Aiping Hu, Xiaohua Chen
Abstract
Abstract The unstable anode/electrolyte interface (AEI) triggers the corrosion reaction and dendrite formation during cycling, hindering the practical application of zinc metal batteries. Herein, for the first time, l ‐cysteine (Cys) is employed to serve as an electrolyte additive for stabilizing the Zn/electrolyte interface. It is revealed that Cys additives tend to initially approach the Zn surface and then decompose into multiple effective components for suppressing parasitic reactions and Zn dendrites. As a consequence, Zn|Zn symmetric cells using trace Cys additives (0.83 m m ) exhibit a steady cycle life of 1600 h, outperforming that of prior studies. Additionally, an average Coulombic efficiency of 99.6% for 250 cycles is also obtained under critical test conditions (10 mA cm −2 /5 mAh cm −2 ). Cys additives also enable Zn–V 2 O 5 and Zn–MnO 2 full cells with an enhanced cycle stability at a low N/P ratio. More importantly, Cys/ZnSO 4 electrolytes are demonstrated to be still effective after resting for half year, favoring the practical production.