Opportunity for lithium-ion conducting polymer electrolytes beyond polyethers

Lithium-ion conducting solid polymer electrolytes (SPEs) are of particular interest for battery applications. In addition to their relatively easy scalability to industrial scale, the ductility and processability of SPEs allows intimate contact between electrode and electrolyte materials, which ensures low cell resistance and thus better cycling performance. Herein, we focus on the non-polyether-based polymers developed for building lithium-ion conducting SPEs, with the aim of circumventing the dilemmas encountered by classic polyether-based SPEs. This review highlights the recent progresses and advances in the development of several kinds of interesting polymer host matrices, including carbonyl-containing polymers [e.g., polycarbonates, polyesters], ionomers-based polymers [e.g., poly(ionic liquids)], fluorine-based polymers, nitrile-based polymers, and so on. Particular attention is paid to the differences between alternative polymer chemistries and polyether systems, in terms of ion transport behavior [e.g., ionic conductivity, cationic transport number], electrochemical properties [e.g., anodic and cathodic stability], compatibility with electrode materials, etc. Possible solutions to further enhance the performances of non-polyether-type SPEs are also discussed.