In Situ Self-Assembly of Ordered Organic/Inorganic Dual-Layered Interphase for Achieving Long-Life Dendrite-Free Li Metal Anodes in LiFSI-Based Electrolyte

Metallic lithium electrode with high capacity of 3860 mA h g(-1) is the most promising candidate for rechargeable batteries. However, some inherent problems such as dendrite growth, uneven solid electrolyte interphase (SEI), and high manufacturing risk restraint its practical application. Herein, distinct from the conventional mosaic structure, a facile fabrication of in situ self-assembled organic/inorganic hybrid SEI with ordered dual-layer structure on the lithium surface to suppress dendrite formation is proposed. With the aid of moderate active fluoric-containing ionic liquid, the as-formed lithium fluoride and robust ordered organic moieties are in situ self-assembled on the metallic lithium surface. The evolution process of the dual-layered structure is revealed by X-ray spectroscopy, in situ sum frequency generation spectroscopy, and atomic force microscopy. The formed double protection ordered hybrid interphase layer also exhibits the surprising ability against the corrosion of carbonate electrolyte or dry air. As a consequence, the pretreated metallic lithium electrode represents excellent stripping/plating reversibility of approximate to 99% and a long lifespan up to 1200 h without formation of dendrite, and remains high performance at a current density of 10 mA cm(-2), which is much higher than most reports, showing the facilitating promising to the future utilization.

Automated summary

A new method of fabricating an ordered dual-layered organic/inorganic hybrid solid electrolyte interphase (SEI) on the surface of metallic lithium has been proposed to suppress dendrite growth, showing excellent electrode performance and corrosion resistance. Studies have revealed the evolution process of the dual-layered structure and the surprising ability of the formed double protection ordered hybrid interphase layer against corrosion.