Tailoring solvation structure enabling in situ construction of nitride interfaces for high-performance lithium metal...

Lithium metal batteries (LMBs) are reckoned as promising next-generation energy storage systems due to their high theoretical capacity and energy density. However, it remains challenging to build a stable and robust solid electrolyte interphase (SEI) of lithium metal anodes in carbonate electrolytes. To address the unstable anode and cathode interfaces in lithium metal batteries during cycling, the effective inorganic additive LiNO₃ was successfully incorporated into a carbonate electrolyte using triethyl phosphate (TEP) as a carrier. Modulation of the electrolyte solvation structure shifted the dominant species in the inner Li⁺ solvation sheath to NO₃^-, facilitating the formation of an anion-induced, inorganic-rich SEI layers. The synergistic effect of LiNO₃ and TEP enabled the Li||Cu cells to achieve an average Coulombic efficiency (CE) of 98.8 % and the Li||Li symmetric cells to exhibit a prolonged cycle life exceeding 1300 h. Meanwhile, excellent cycling stability of full cells was also achieved coupled with LiNi_0.83Co_0.11Mn_0.06O₂ and LiNi_0.9Co_0.05Mn_0.05O₂ cathodes. Ah-level Li||LiNi_0.9Co_0.05Mn_0.05O₂ (NCM90) pouch cells exhibited stable cycling with an average CE of 98.8 % under harsh conditions of high-loading NCM90 cathodes, low N/P ratio, and lean electrolyte. This work provides a promising and effective strategy to regulate the electrolyte solvation structure and interface components for high-performance LMBs.