Non‐Resonant Structure Induces N‐Rich Solid Electrolyte Interface toward Ultra‐Stable Solid‐State Lithium‐Metal Batteries

Abstract The practical application of all‐solid‐state lithium metal batteries (ASSLMBs) is limited by lithium (Li) anode instability including Li dendrite formation and deteriorating interface with electrolytes. Here, a functional additive, isosorbide mononitrate (ISMN) with a non‐resonant structure (O₂−N−O−) is reported, which improves its reactivity and is utilized to build a stable N‐rich solid electrolyte interface, effectively alleviating Li dendrite and side reactions for poly(vinylidene fluoride) (PVDF)‐lithium bis(trifluoromethane sulfonyl) imide (LiTFSI)‐based electrolyte (PLE‐ISMN). In addition, the ion‐dipole interaction between ISMN and Li ions facilitates the dissociation of LiTFSI to form carrier ions, improving the ionic conductivity (4.4 × 10⁻⁴ S cm⁻¹) and transference number (0.50) of PLE‐ISMN. Consequently, the Li/Li symmetric cell delivers a high critical current density of 2.0 mA cm⁻² and stable Li stripping/plating cycling over 5000 h with a capacity of 1.0 mAh cm⁻². Moreover, the Li|LiFePO₄ cell delivers an excellent initial discharge capacity of 154.0 mAh g⁻¹ with an outstanding capacity retention of 88.9% after 500 cycles at 0.5 C. The Li|LiNi_0.8Co_0.1Mn_0.1O₂ cell also exhibits a good cycling performance at 4.4 V at 1 C.