Tailoring Practical Solid Electrolyte Composites Containing Ferroelectric Ceramic Nanofibers and All-Trans Block Copolymers for All-Solid-State Lithium Metal Batteries.

Ion transport efficiency, the key to determining the cycling stability and rate capability of all-solid-state lithium metal batteries (ASSLMBs), is constrained by ionic conductivity and Li + -migration ability across the multicomponent phases and interfaces in ASSLMBs. Here, we report a robust strategy for the large-scale fabrication of a practical solid electrolyte composite with high-throughput linear Li + -transport channels by compositing an all-trans block copolymer PVDF- b -PTFE matrix with ferroelectric BaTiO 3 -TiO 2 nanofiber films. The electrolyte shows a sustainable electromechanical-coupled deformability that enables the rapid dissociation of anions with Li + to create more movable Li + ions and spontaneously transform the battery internal strain into Li + -ion migration kinetic energy. The ceramic framework homogenizes the interfacial potential with electrodes, endowing the electrolyte with a high conductivity of 0.782 mS·cm -1 and stable ion transport ability in ASSLMBs at room temperature. The batteries of LiFePO 4 /Li can stably cycle 1000 times at 0.5 C with a high capacity retention of 96.1%, and Ah-grade pouch or high-voltage Li(Ni 0.8 Mn 0.1 Co 0.1 )O 2 /Li batteries also exhibit excellent rate capability and cycling performance.