Interfacial solvation- structure regulation for stable Li metal anode by a desolvation coating technique

• 成果类型: Article
• 署名作者: Li, Guo-Xing; Lennartz, Peter; Koverga, Volodymyr; Kou, Rong; Nguyen, Au; Jiang, Heng; Liao, Meng; Wang, Daiwei; Dandu, Naveen; Zepeda, Michael; Wang, Haiying; Wang, Ke; Ngo, Anh T.; Brunklaus, Gunther; Wang, Donghai
• 署名单位: Pennsylvania Commonwealth System of Higher Education (PCSHE); Pennsylvania State University; Pennsylvania State University - University Park; Helmholtz Association; Research Center Julich; University of Illinois System; University of Illinois Chicago; University of Illinois Chicago Hospital; United States Department of Energy (DOE); Argonne National Laboratory; Pennsylvania Commonwealth System of Higher Education (PCSHE); Pennsylvania State University; Pennsylvania State University - University Park; Pennsylvania Commonwealth System of Higher Education (PCSHE); Pennsylvania State University; Pennsylvania State University - University Park
• 刊物名称: PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA
• ISSN/ISSBN: 0027-11418
• DOI: 10.1073/pnas.2311732121
• 发表日期: 2024-01-23
• 关键词: high-energy; lithium-ion; electrolytes; batteries; liquid; interphases; carbonate

摘要

Rechargeable lithium (Li) metal batteries face challenges in achieving stable cycling due to the instability of the solid electrolyte interphase (SEI). The Li - ion solvation structure and its desolvation process are crucial for the formation of a stable SEI on Li metal anodes and improving Li plating/stripping kinetics. This research introduces an interfacial desolvation coating technique to actively modulate the Li - ion solvation structure at the Li metal interface and regulate the participation of the electrolyte solvent in SEI formation. Through experimental investigations conducted using a carbonate electrolyte with limited compatibility to Li metal, the optimized desolvation coating layer, composed of 12- crown-4 ether- modified silica materials, selectively displaces strongly coordinating solvents while simultaneously enriching weakly coordinating fluorinated solvents at the Li metal/electrolyte interface. This selective desolvation and enrichment effect reduce solvent participation to SEI and thus facilitate the formation of a LiF- dominant SEI with greatly reduced organic species on the Li metal surface, as conclusively verified through various characterization techniques including XPS, quantitative NMR, operando NMR, cryo-TEM, EELS, and EDS. The interfacial desolvation coating technique enables excellent rate cycling stability (i.e., 1C) of the Li metal anode and prolonged cycling life of the Li||LiCoO2 pouch cell in the conventional carbonate electrolyte (E/C 2.6 g/Ah), with 80% capacity retention after 333 cycles.