Integrating Electric Ambipolar Effect for High-Performance Zinc Bromide Batteries
Wenda Li, Hengyue Xu, Shanzhe Ke, Hongyi Zhang, Hao Chen, Gaijuan Guo, Xuanyi Xiong, Shiyao Zhang, Jianwei Fu, Chengbin Jing, Jiangong Cheng, Shaohua Liu
Abstract
Abstract The coupling of fast redox kinetics, high-energy density, and prolonged lifespan is a permanent aspiration for aqueous rechargeable zinc batteries, but which has been severely hampered by a narrow voltage range and suboptimal compatibility between the electrolytes and electrodes. Here, we unprecedentedly introduced an electric ambipolar effect for synergistic manipulation on Zn 2+ ternary-hydrated eutectic electrolyte (ZTE) enabling high-performance Zn-Br 2 batteries. The electric ambipolar effect motivates strong dipole interactions among hydrated perchlorates and bipolar ligands of L-carnitine (L-CN) and sulfamide, which reorganized primary cations solvation sheath in a manner of forming Zn[(L-CN)(SA)(H 2 O) 4 ] 2+ configuration and dynamically restricting desolvated H 2 O molecules, thus ensuring a broadened electrochemical window of 2.9 V coupled with high ionic conductivity. Noticeably, L-CN affords an electrostatic shielding effect and an in situ construction of organic–inorganic interphase, endowing oriented Zn anode plating/stripping reversibly for over 2400 h. Therefore, with the synergy of electro/nucleophilicity and exceptional compatibility, the ZTE electrolyte dynamically boosts the conversion redox of Zn-Br 2 batteries in terms of high specific capacity and stable cycling performance. These findings open a window for designing electrolytes with synergetic chemical stability and compatibility toward advanced zinc-ion batteries.