TECHNOLOGY FOCUS - POLYMERS - Preferred Compounds: The aromatic polyether polymer film comprises polyphenylene oxide polymer, or is chosen from poly(2,6-dimethyl-1,4-phenylene oxide), poly(2,6-diphenyl-1,4-phenylene oxide) and poly(2,6-dibutyl-1,4-phenylene oxide). The polyether polymer film further comprises polyethylene oxide, polypropylene oxide, polysulfone, polyarylate and/or polycarbonate. The organic solvent comprises propylene carbonate, ethylene carbonate, diethyl carbonate, dimethyl carbonate, dipropyl carbonate, tetrahydrofuran, gamma-butyrolactone, toluene and/or chloroform. The organic solvent is free from diethyl ether and/or diethylene glycol.Preferred Composition: The composition used as polymer gel electrolyte comprises 100 weight parts of polymeric support material, impregnated with 18.5-26.5 weight parts of lithium salt(s). The plasticizer solution comprises 18.5-26.5 g of lithium salt(s) in 160-274 ml of organic solvent(s). The polymeric support preferably comprises 87-92 wt.pts. of polyphenylene oxide and 8-13 wt.pts. of polysulfone, or 85-95 wt.pts. of polyphenylene oxide and 5-15 wt.% of polyethylene oxide, or 86-95 wt.pts. of polyphenylene oxide and 5-14 wt.pts. of polyarylate, or 86-95 wt.pts. of polyphenylene oxide and 5-14 wt.pts. of polycarbonate. The polymeric support comprises a mixture of toluene and gamma-butyrolactone in equal volume parts, a mixture of 1 volume part of toluene, 1 volume of tetrahydrofuran and 2 volume of propylene carbonate, or a mixture of 3 volume of chloroform and 1-2 volume of propylene carbonate.    TECHNOLOGY FOCUS - INORGANIC CHEMISTRY - Preferred Materials: The alkali metal salt is lithium salt chosen from lithium perfluoroborate (LiBF4) and lithium perchlorate (LiClO4). EXAMPLE - 1 M solution of lithium chlorate (26 g) was added to polypropylene oxide powder (100 g) and the mixture was allowed to stay for 18-24 hours in an inert atmosphere at room temperature until a gel was formed. The amount of solvent mixture comprising toluene and propylene carbonate used was 200 ml and the volume ratio of toluene to propylene carbonate was 4:1. The conductivity of the polymer electrolyte gel obtained was 2.1 x 10 to the power -2 at room temperature and 7.0 x 10 to the power -3 at -30 degreesC.    A battery was prepared by placing the gel between lithium anode and lithium manganate cathode. The electrolyte gel was tested in LiMnO2 primary elements and in Li-LiV3O8 accumulators. The primary elements had service life of 140-150 hours at 20 degreesC and 115-125 hours at -15 degreesC.