Abstract: A cross-linked copolymer is provided, including at least repeating units of poly(alkylene oxide) and at least repeating units of lithium polystyrene-sulfonyl(trifluoromethylsulfonyl)imide (PSTFSILi), as well as the use of such a cross-linked copolymer for preparing a solid polymer electrolyte, a solid polymer electrolyte having the cross-linked copolymer, and a battery, for example a lithium metal polymer (LMP) battery, including the solid polymer electrolyte.

Abstract: The invention relates to an improved solid polymer electrolyte SPE, in particular for storage batteries, and, even more particularly, for LMP storage batteries. The objective of the invention is to provide a SPE that has, at low temperatures (?40° C.), both high ionic conductivity and very good mechanical qualities in the solid state, which can limit or even eliminate the dendritic growth of metal in the storage battery, in this case lithium in LMP storage batteries. To this end, the invention first and foremost relates to a Solid Polymer Electrolyte (SPE) comprising: 1.