Solvation Engineering with 2D Laponite Nanosheets for Stable Aqueous Zinc‐Ion Batteries

Aqueous zinc‐ion batteries (AZIBs) have attracted widespread attention as promising candidates for next‐generation energy storage systems, owing to their inherent safety advantages, affordability, and eco‐friendly characteristics. However, their development has been severely hindered by poor reversibility of the Zn metal and side reactions induced by the high water activity in aqueous electrolytes. Regulating the solvation structures of Zn ions (Zn 2+ ) has emerged as an effective strategy to address these challenges. Herein, Zn‐based laponite nanosheets (ZBL) were developed and used as an electrolyte additive. Especially, ZBL can be evenly dispersed in the electrolyte and effectively modulates the Zn 2+ solvation structure, thereby promoting uniform Zn 2+ stripping/plating and suppressing the corrosion of Zn anodes. As a result, a Zn||Zn symmetric cell with the addition of ZBL exhibits stable cycling exceeding 3200 h at a charge density of 5 mA cm −2 and a capacity of 1 mAh cm −2 . Moreover, the ZBL‐based Zn||vanadium pentoxide full cell exhibits good cycling stability over 3000 cycles at 2 A g −1 in coin cells and over 500 cycles at 1 A g −1 in pouch cells. These results highlight the significant potential of ZBL as an electrolyte additive for stable AZIBs.