3d Nanofiber Framework Based on Polyacrylonitrile and Siloxane-Modified Li6.4la3zr1.4ta0.6o12 Reinforced Poly (Ethylene Oxide)-Based Composite Solid Electrolyte for Lithium Batteries

The application of solid-state electrolytes in lithium metal batteries is promising for next-generation high-energy density battery systems. Poly (ethylene oxide) (PEO)-based solid polymer electrolytes have been widely studied, but their electrochemical window is too narrow to be compatible with high-voltage cathodes and their mechanical properties are poor. Combining organic and inorganic compounds is an effective approach to solve this limitation. In this study, Li 6.4 La 3 Zr 1.4 Ta 0.6 O 12 (LLZTO) was surface-modified with a silane coupling agent and compounded with polyacrylonitrile (PAN) to form a 3D nanofiber framework via electrospinning technology, and the PEO-succinonitrile (SN)-LiTFSI solution was uniformly dispersed in the 3D nanofiber framework to form a continuous Li + transport path. The prepared composite solid electrolytes (CSEs) show high ionic conductivity (1.58 × 10 −4 S cm −1 at room temperature), a broad electrochemical window (5.1 V, vs . Li/Li + ), and an attractive mechanical strength of 49.4 MPa. In addition, solid-state Li/CSE/NCM811 batteries exhibited high Coulombic efficiency and significant stable cycling performance.