Photo-crosslinked Polymer Electrolytes Containing Solvate Ionic Liquids: An Approach to Achieve Both Good Mechanical and Electrochemical Performances for Rechargeable Lithium Ion Batteries

Development of innovative polymer electrolytes that simultaneously possesses high mechanical stiffness as well as liquid-like ion motions is desirable for safer lithium-ion secondary batteries. Herein, bifunctional poly(ethylene glycol) diacrylate (PEGDA) based cross-linked network polymer electrolytes (PE) plasticized by tetraglyme at various lithium salt concentrations were fabricated via a solvent-free UV-curing process using a photo-initiator, 2,2-dimethoxy-2-phenylacetophenone (DMAP). The outstanding results demonstrate potential for safer high-performance rechargeable lithium-ion batteries. A series of soft cross-linked network polymer electrolytes based on poly(ethylene glycol) diacrylate is architectured and prepared via solvent-free, clean, and fast in-situ UV-curing. Self-supporting polymer electrolytes showed high thermal stability, high ionic conductivites values exceeding 0.1 mS cm−1, wide electrochemical stability window, good lithium transference number as well as interfacial stability, and uniform lithium stripping and plating over long hours of operation, which establishes their strong potential for rechargeable lithium ion batteries.