Advanced inorganic/polymer hybrid electrolytes for all-solid-state lithium batteries

Abstract Solid-state batteries have become a frontrunner in humankind’s pursuit of safe and stable energy storage systems with high energy and power density. Electrolyte materials, currently, seem to be the Achilles’ heel of solid-state batteries due to the slow kinetics and poor interfacial wetting. Combining the merits of solid inorganic electrolytes (SIEs) and solid polymer electrolytes (SPEs), inorganic/polymer hybrid electrolytes (IPHEs) integrate improved ionic conductivity, great interfacial compatibility, wide electrochemical stability window, and high mechanical toughness and flexibility in one material, having become a sought-after pathway to high-performance all-solid-state lithium batteries. Herein, we present a comprehensive overview of recent progress in IPHEs, including the awareness of ion migration fundamentals, advanced architectural design for better electrochemical performance, and a perspective on unconquered challenges and potential research directions. This review is expected to provide a guidance for designing IPHEs for next-generation lithium batteries, with special emphasis on developing high-voltage-tolerance polymer electrolytes to enable higher energy density and three-dimensional (3D) continuous ion transport highways to achieve faster charging and discharging.