A high-performance polymer composite electrolyte embedded with ionic liquid for all solid lithium based batteries operating at ambient temperature

[Display omitted] Polymer composite electrolyte embedding ionic liquid to fabricate the high-performance all-solid-state Li-battery operating at room temperature. The proposed electrolyte shows a high ionic conductivity 35×10−2mScm−1. When polymer composite electrolyte is applied to the battery, it can be operated at room temperature. •Polymer composite electrolytes were composed with the 3-D cross-linked polymer matrix and EMITFSI.•The suggested polymer composite electrolyte was thermally stable up to 250°C.•Ionic conductivity was strongly increased by addition of EMITFSI to polymer composite electrolyte.•Polymer composite electrolyte achieved a high ionic conductivity of 35×10−2mScm−1 at room temperature.•The discharge specific capacity of Li/polymer composite electrolyte/LiFePO4 battery was increased to 75.8mAh/g at room temperature. A novel polymer composite electrolyte for lithium-based battery operating at room temperature was introduced. The proposed polymer composite electrolyte consisted of electrolyte using a 3-D cross-linked polymer matrix, which is synthesized with polyethylene glycol (PEG) and 3-glycidoxypropyltrimethoxysilane (GPTMS), and 1-ethyl-3-methylimidazolium bis(trifluoromethylsulfonyl)imide (EMITFSI) as a Li-ion transport medium. The proposed polymer composite electrolyte shows a high ionic conductivity of 35×10−2mScm−1 and high decomposition temperature of 250°C with a 3-D cross-linked polymer matrix. The EMITFSI mass ratio is 1:0.7 at room temperature. In addition, when polymer composite electrolyte is applied to the solid battery consisting of Li metal as an anode and LiFePO4 as a cathode, it can be operated at room temperature with a high specific capacity of 75.8mAh/g at 0.1C rate. Furthermore, the battery with a structure of Li/polymer composite electrolyte/LiFePO4 also has excellent capacity retention.