ScholarWorks@성균관대학교

초록

Solid polymer electrolytes (SPEs) are promising for safe and scalable all-solid-state lithium batteries, but low-temperature ionic transport and interfacial instability limit their practical use. Here, we present a fluorinated-ether (FE)-anchored polymer electrolyte (FAPE) based on a PEGDME semi-interpenetrating network, designed to overcome these challenges. FE units anchor onto ether chains via C−H···O interaction, suppressing crystallization, weakening Li⁺–EO coordination, and promoting formation of inorganic-rich, anion-derived interphases. FAPE exhibits high ionic conductivity down to −20 °C, intrinsic nonflammability, and an expanded electrochemical stability window. Lithium metal cells with FAPE demonstrate enhanced Coulombic efficiency, extended cycling stability, and higher critical current densities compared to conventional PEGDME-based SPEs. Full cells and prototype pouch cells retain high capacities under both ambient and sub-zero temperatures, highlighting their practical applicability. This molecular anchoring strategy provides a versatile platform to tailor solvation structure and interphase chemistry, enabling wide-temperature, safe, and durable operation in high-energy solid-state lithium metal batteries.

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