Tuning the Li<sup>+</sup> Solvation Structure by a “Bulky Coordinating” Strategy Enables Nonflammable Electrolyte for Ultrahigh Voltage Lithium Metal Batteries
Yang Lu, Weili Zhang, Shengzhou Liu, Qingbin Cao, Shuaishuai Yan, Hao Liu, Wenhui Hou, Pan Zhou, Xuan Song, Yu Ou, Yong Li, Kai Liu
Abstract
In battery electrolyte design principles, tuning Li + solvation structure is an effective way to connect electrolyte chemistry with interfacial chemistry. Although recent proposed solvation tuning strategies are able to improve battery cyclability, a comprehensive strategy for electrolyte design remains imperative. Here, we report a solvation tuning strategy by utilizing molecular steric effect to create a “bulky coordinating” structure. Based on this strategy, the designed electrolyte generates an inorganic-rich solid electrolyte interphase (SEI) and cathode–electrolyte interphase (CEI), leading to excellent compatibility with both Li metal anodes and high-voltage cathodes. Under an ultrahigh voltage of 4.6 V, Li/NMC811 full-cells ( N / P = 2.0) hold an 84.1% capacity retention over 150 cycles and industrial Li/NMC811 pouch cells realize an energy density of 495 Wh kg –1 . This study provides innovative insights into Li + solvation tuning for electrolyte engineering and offers a promising path toward developing high-energy Li metal batteries.