Highly Adaptable Poly(ether-acrylate) Solid Electrolyte for Cathode/Electrolyte Interface Integration and Application in Lithium Metal-Free Solid-State Batteries

Solid polymer electrolyte is expected to be widely used in solid-state lithium batteries due to its good manufacturability and safety. But the low ion conductivity, poor interface combination, and narrow adaptability to different electrodes are hindering the development of solid-state batteries. In this work, a rigid-flexible poly(ether-acrylate) (PEA) solid electrolyte membrane with high room-temperature ion conductivity (1.5 × 10–4 S/cm), electrochemical stability window (∼4.8 V), and lithium ion migration number (0.81) was prepared using a cross-linking polymerization method. The cathode/electrolyte integrated structure was also created via directly coating electrolyte precursor on the cathode surface to improve the cathode/electrolyte interface combination and decrease the interface impedance, which obviously enhanced the rate performance of the battery. This electrolyte is suitable for LiFePO4, LiCoO2, NCM622 different-voltage cathodes and lithium metal, Si–C, and graphite anodes, showing good practicality and development prospects in solid-state lithium and lithium metal-free batteries due to its good adaptability.