Solid polymer electrolytes based on the composite of PEO–LiFSI and organic ionic plastic crystal

In this work, composite membranes consisting of triethylmethylammonium bis(fluorosulfonyl)imide (N1222FSI), poly(ethylene oxide) (PEO) and lithium bis(fluorosulfonyl) imide (LiFSI) have been produced as solid polymer electrolytes (SPEs). The composite SPEs provide good mechanical property, high ionic conductivity at 50 °C, high electrochemical and thermal stability as well as superior interfacial compatibility with lithium metal. Moreover, Li/LiFePO4 cells containing the best-performing SPE exhibit high discharge capacity and excellent cycling performance. The results show that the novel composite SPEs might be promising electrolytes applied in all-solid-state lithium batteries.