Liu Chengkun, Ren Kaixiang, Wu Shilin, Zhang Yuhang, Li Hai-Wen, Yao Meng, Jiang Zhipeng, Li Yongtao
School of Materials Science and Engineering, Anhui University of Technology, Maanshan 243002, China.
School of Advanced Energy, Sun Yat-sen University, Shenzhen 518107, China.
Nano Lett. 2025 May 14;25(19):7762-7769. doi: 10.1021/acs.nanolett.5c00675. Epub 2025 Apr 30.
Developing high-energy-density lithium metal batteries (LMBs) necessitates robust solid electrolyte interphases (SEIs) capable of enduring prolonged cycling. While lithium fluoride (LiF) is recognized as crucial for lithium metal anode (LMA) protection, the effects of different LiF sources in SEIs remain insufficiently understood. In this study, we systematically introduce single fluorine sources─anion LiF, solvent LiF, and native LiF─into a fluoride-free electrolyte system to elucidate the impact of LiF originating from different sources on the SEI composition and properties. Results reveal that SEI performance depends not only on LiF content but also on coexisting organic components. During deep cycling, solvent-derived LiF-rich SEIs, containing elevated LiF and organics, offer superior LMA protection ability. These SEIs maintain structural integrity during significant volume changes, effectively suppressing dead Li formation and achieving enhanced Coulombic efficiency. This work reexamines LiF's protective mechanisms while advancing SEI chemistry understanding, providing critical insights for developing high-performance LMBs.
开发高能量密度锂金属电池（LMBs）需要能够承受长时间循环的坚固固体电解质界面（SEIs）。虽然氟化锂（LiF）被认为对锂金属阳极（LMA）的保护至关重要，但不同LiF来源在SEIs中的作用仍未得到充分理解。在本研究中，我们系统地将单一氟源——阴离子LiF、溶剂LiF和原生LiF——引入无氟电解质体系，以阐明不同来源的LiF对SEI组成和性能的影响。结果表明，SEI性能不仅取决于LiF含量，还取决于共存的有机成分。在深度循环过程中，富含溶剂衍生LiF的SEIs，含有更高的LiF和有机物，具有卓越的LMA保护能力。这些SEIs在显著的体积变化过程中保持结构完整性，有效抑制死锂形成并提高库仑效率。这项工作重新审视了LiF的保护机制，同时推进了对SEI化学的理解，为开发高性能LMBs提供了关键见解。
