Uncovering the critical impact of the solid electrolyte interphase structure on the interfacial stability

Solid electrolyte interphase (SEI) plays a critical role in determining the interfacial stability, which turn impacts plating/stripping process of lithium metal anode. Substantial research has been focused on composition SEI and its contribution to stability. Herein, we illustrate significance structure, comprehensive comparison diluted (1 M LiTFSI-PC) super-concentrated (8 LiTFSI-PC). Illustrated by situ optical atomic force microscope observation, homogeneous plating anode is achieved concentrated electrolyte. However, x-ray photoelectron spectroscopy molecular dynamics simulations reveal that, contrary general understanding, components nearly identical for cycled both two electrolytes. Detailed characterizations demonstrate structure quite different. In electrolyte, compact layer can be obtained, mainly due reduced solubility outstanding formation kinetics layer. This work provided new understanding excellent performance battery.