Mechanically Strong and Tough Ionic Liquid Gel Electrolyte for Four-Electron Zinc–Iodine Batteries

作者：Zuyang Hu, Zixin Han, Haoxin Liu, Xiaolong Jiang, Kai Bai, Shengyang Huang, Zican Yang, Minghui Ye, Yongchao Tang, Yufei Zhang, Xiaoqing Liu, Zhipeng Wen, Ho Seok Park, Chengchao Li · 发表于：Journal of the American Chemical Society · 年份：2025 · DOI：10.1021/jacs.5c18431 · 被引用次数：35 · 研究领域：Advanced battery technologies research、Advanced Battery Materials and Technologies、Ionic liquids properties and applications

Interfacial stress accumulation and dendrite penetration constitute the fundamental origins of cycle life degradation in solid-state zinc ion batteries, necessitating polymer electrolytes with both high mechanical strength and high toughness. Nevertheless, constructing double-high-polymer electrolytes through molecular design to enhance dynamic interface compliance remains a persistent challenge. In this study, to achieve long-term stabilized Zn chemistry, a supramolecular ionic liquid gel electrolyte was developed by a solvent exchange process through noncovalent interaction, which consists of PVA and ionic liquid (IL, Bmim[ZnBr 3 ]/Bmim[ZnCl 3 ]). The stable supramolecular effect (Br–H bond and H-bond) of IL endows the electrolyte with high strength (2.22 MPa tensile strength, more than 1200% deformation) and high toughness (1900.74 MJ/m 3 ), and the long-term cycle life of the anode (over 2000 h) can be achieved through the unique stress dissipation mechanism. Besides, the polyanionic groups ([ZnBr 3 ] − ) of IL activate the −OH site activity of PVA by changing the distribution of electrons, which enhance binding of Zn 2+ to the site, realizing a high Zn 2+ transference number (0.61) and ionic conductivity (0.739 mS cm –1 ). In addition, the low water content and Br – -rich chemical environment contribute to the formation of [IBr 2 ] − polyhalide via interhalogen nucleophilic interactions, stabilizing the realization of the iodine four-electron reaction (0.2 A g –1, 4000 c...