Customized Li+ Solvation Sheath at the Poly(ethylene oxide)-Based Electrolyte/Ultrahigh-Nickel Cathode Interface toward Room-Temperature Solid-State Lithium Batteries

The matching of poly(ethylene oxide) (PEO)-based electrolytes with ultrahigh-nickel cathode materials is crucial for designing new-generation high-energy-density solid-state lithium metal batteries (SLMBs), but it is limited by serious interfacial side reactions between PEO and ultrahigh-nickel materials. Here, a high-concentration electrolyte (HCE) interface with a customized Li