Strong Lewis Acid-Base and Weak Hydrogen Bond Synergistically Enhancing Ionic Conductivity of Poly(ethylene oxide)@SiO2 Electrolytes for a High Rate Capability Li-Metal Battery

Solid-state composite polymer electrolytes (CPEs) usually suffer from intrinsic low ionic conductivity and a solidsolid interface, badly inhibiting their widespread commercial application in all-solid-state Li-metal battery (ASSLMB) energy storage. Herein, a synergetic strategy using strong Lewis acid-base and weak hydrogen bonds was employed for self-assembly in situ construction of three-dimensional (3D) network-structured poly(ethylene oxide) (PEO) and SiO2 CPEs (PEO@SiO2). Ascribed to this synergistically rigid-flexible coupling dynamic strategy, a harmonious incorporation of monodispersed SiO2 nanoparticles into PEO could remarkably reduce crystallinity of PEO, significantly enhancing the ionic conductivity (similar to 1.1 X 10(-4) S cm(-1) at 30 degrees C) and dramatically facilitating solid electrolyte interface stabilization (electrochemical stability window > 4.8 V at 90 degrees C). Moreover, the PEO@SiO2-based ASSLMBs possess excellent rate capability over a wide temperature range (similar to 105 mA h g(-1) under 2 C at 90 degrees C), high temperature cycling capacity (retaining 90 mA h g(-1) after 100 cycles at 90 degrees C), and high specific capacity (146 mA h g(-1) under 0.3 C at 90 degrees C). Unambiguously, these high ionic conductivity CPEs along-with excellent flexibility and safety can be one of the most promising candidates for high-performance ASSLMBs, evidently revealing that this synergistically rigid-flexible coupling dynamic strategy will open up a way to exploit the novel high ionic conductivity solid-state electrolytes.