Optimization of high potential cathode materials and lithium conducting hybrid solid electrolyte for high-voltage all-solid-state batteries

Preparation and Study of a Simple Three-Matrix Solid Electrolyte Membrane in Air

Solid-state lithium batteries have attracted much attention due to their special properties of high safety and high energy density. Among them, the polymer electrolyte membrane with high ionic conductivity and a wide electrochemical window is a key part to achieve stable cycling of solid-state batteries. However, the low ionic conductivity and the high interfacial resistance limit its practical application. This work deals with the preparation of a composite solid electrolyte with high mechanical flexibility and non-flammability. Firstly, the crystallinity of the polymer is reduced, and the fluidity of Li⁺ between the polymer segments is improved by tertiary polymer polymerization. Then, lithium salt is added to form a solpolymer solution to provide Li⁺ and anion and then an inorganic solid electrolyte is added. As a result, the composite solid electrolyte has a Li⁺ conductivity (3.18 × 10^-4 mS cm^-1). The (LiNi_0.5Mn_1.5O₄)LNMO/SPLL (PES-PVC-PVDF-LiBF₄-LAZTP)/Li battery has a capacity retention rate of 98.4% after 100 cycles, which is much higher than that without inorganic oxides. This research provides an important reference for developing all-solid-state batteries in the greenhouse.