Stable Interface Chemistry and Multiple Ion Transport of Composite Electrolyte Contribute to Ultra‐long Cycling Solid‐State LiNi 0.8 Co 0.1 Mn 0.1 O 2 /Lithium Metal Batteries

The severe interfacial side reactions of polymer electrolyte with LiNi0.8Co0.1Mn0.1O2 (NCM811) cathode and lithium (Li) metal anode become huge challenge to restrict ultra-stable cycling performance of solid-state NCM811/Li batteries. Herein, we propose a chemically stable ceramic-polymer-anchored solvent composite electrolyte with high ionic conductivity of 6.0×10-4 S cm-1, which enables the solid-state NCM811/Li batteries to stably cycle for 1500 times. The Li1.4Al0.4Ti1.6(PO4)3 nanowires (LNs) can tightly anchor the essential N, N-dimethylformamide (DMF) in poly(vinylidene fluoride) (PVDF), which greatly enhances its electrochemical stability and suppresses the side reactions. We clearly identify the ceramic-polymer-liquid multiple ion transport mechanism of the LNs-PVDF-DMF composite electrolyte by tracking the 6Li and 7Li substitution behavior via solid-state nuclear magnetic resonance, which endow homogeneous and efficient ions flux and uniform lithium depositions. The stable interface chemistry and efficient ion transport of LNs-PVDF-DMF contribute to superior performances of the solid-state batteries at wide temperature range of -20~60 oC.