Molecular Adsorption‐Induced Interfacial Solvation Regulation to Stabilize Graphite Anode in Ethylene Carbonate‐Free Electrolytes

Abstract

AbstractMany organic solvents have excellent solution properties, but fail to serve as lithium‐ion batteries (LIBs) electrolyte solvents, due to their electrochemical incompatibility with graphite anodes. Herein, a new strategy is proposed to address this issue by introducing a surface‐adsorbed molecular layer to regulate the interfacial solvation structure without the alteration of electrolyte composition and properties. As a proof‐of‐concept study, it is demonstrated for the first time that the intrinsically incompatible propylene carbonate (PC)‐based electrolyte becomes completely compatible with graphite anodes by introducing a layer of adsorbed hexafluorobenzene (HFB) molecules to weaken the Li+‐PC coordination strength and facilitate the interfacial desolvation process. As a consequence, the graphite/ NCM811 pouch cells using the PC‐based electrolyte containing only 1 vol.% HFB demonstrate excellent long‐term cycling stabilities over 1150 cycles. This strategy is also proved to be applicable to other ethylene carbonate (EC)–free electrolytes, thus providing a new avenue for developing advanced LIB electrolytes.