Gel Polymer Electrolytes Based on Polymerizable Lithium Salt and Poly(ethylene glycol) for Lithium Battery Applications

Here, a polymerizable lithium salt, lithium (trifluoromethanesulfonyl)(vinylsulfonyl)imide, was synthesized and used to prepare cross-linked gel polymer electrolyte systems with poly(ethylene glycol) methyl ether methacrylate as an ion-conducting moiety, poly(ethylene glycol) dimethacrylate as a cross-linker, and propylene carbonate as a liquid electrolyte without adding any conventional inorganic lithium salt. The gel polymer electrolytes prepared in this study exhibited a reasonably high ionic conductivity (6.7 × 10–4 S cm–1 at 25 °C and 1.8 × 10–3 S cm–1 at 60 °C) and lithium-ion transference number (0.52), and the lithium battery prepared using the gel polymer electrolyte showed a stable cycling performance over 50 cycles.