Solid polymer electrolyte based on polymerized ionic liquid for high performance all-solid-state lithium ion batteries

Polymerized ionic liquids (PILs) have several advantages over ionic liquids, such as easy handling, good electrochemical performance and chemical compatibility. In this research, a solid state electrolyte composite membrane was successfully fabricated by using an imidazolium-based polymerized ionic liquid as polymer matrix, a kind of porous fiber cloth as rigid frame and lithium bis(trifluoromethanesulfonyl)imide (LiTFSI ) as lithium salt. The ionic conductivity of composite electrolyte with 2.0 mol / kg LiTFSI is 7.78 × 10-5 S cm-1 at 30 °C and reaches 5.92 × 10-4 S cm-1 at 60 °C, which is considered a satisfactory value for potential application in lithium-ion batteries. The specific discharge capacity of the LiFePO4 / Li cell with as-prepared composite electrolyte is 138.4 mA h g-1 and 90% of the discharge capacity is retained after 250 cycles at 60 °C. In order to further improve the conductivity, Li1.3Al0.3Ti1.7(PO4)3 (LATP) ceramic electrolyte particles are dispersed in PIL polymer matrix to prepare...