A novel flexible composite solid electrolyte based on 3D network structural inorganic Si-Zr-O-C fiber film

Both inorganic solid electrolytes and organic polymer solid electrolytes face limitations in practical applications due to their shortcomings. Inorganic solid electrolytes suffer from high interface impedance and poor mechanical properties, while polymer solid electrolytes struggle with low Li-ion conductivity, thermal stability and electrochemical stability. To overcome the drawbacks of single phase solid electrolytes while utilizing their respective advantages, composite solid electrolytes have emerged as a popular research direction in recent years. Typical composite solid electrolytes feature inorganic filler particles dispersed in a polymer matrix. In this work, we introduce a novel non-flammable composite solid electrolyte with inorganic matrix and inorganic fillers. The composite solid electrolyte was prepared by integrating a 3D Si-Zr-O-C inorganic fiber film with Li 6.4 La 3 Zr 1.4 Ta 0.6 O 12 (LLZTO) particles that have high ionic conductivity via a vacuum impregnation process, which is all-inorganic solid state electrolyte. This unique design of established network structure provides fast Li-ion transport channels, enabling high ionic conductivity (2.3 × 10 −4  S cm −1 at room temperature). Furthermore, the Si-Zr-O-C/LLZTO (SLTO) composite electrolyte also exhibits superior flexibility, thermal stability, and electrochemical stability. The SLTO composite solid electrolyte presents a promising electrolyte candidate for next generation lithium ion batteries.