TECHNOLOGY FOCUS - ELECTRICAL POWER AND ENERGY - Preferred Component: The electrolyte is a cationic conductor.    TECHNOLOGY FOCUS - CERAMICS AND GLASS - Preferred Composition: The composition comprises ionic conducting material ( approximately 0.1-80, preferably approximately 0.1-20) vol.% from glassy lithium ion conductors or ceramic lithium ion conductors. The lithium ion conducting material is sulfide glasses, lithium beta alumina, lithium silicates, lithium phosphorus oxynitride, or other phosphate glasses.    TECHNOLOGY FOCUS - INORGANIC CHEMISTRY - Preferred Composition: The metal salt ( approximately 1-25 wt.%) is sodium, potassium, magnesium, or calcium, preferably lithium. The lithium salt is lithium hexafluorophosphate, lithium perchlorate, lithium tetrafluoroborate, lithium hexafluoroarsenate, lithium tetrachloroaluminate, lithium trifluoromethanesulfonate, lithium methide, lithium bis(trifluoromethane sulfonyl)imide, or plasticizer salt. The electrolyte comprises inorganic filler ( approximately 0.1-60, preferably approximately 0.1-20) vol.% from fumed silica or alumina.    TECHNOLOGY FOCUS - POLYMERS - Preferred Component: The electrolyte comprises approximately 30-95 wt.% base polymer material. The base polymer material comprises at least two polymers, the first polymer ( approximately 1-99%) is an ionically conductive polymer, the monomers of which have a hetero atom with a lone pair of electrons for the metal ions of a metal salt to attach to and move between during conduction when the first polymer is mixed with a metal salt. The first polymer is linear polymers, random polymers, block copolymers, comb-branched block copolymers, network structures, single ion conductors, polyvinylidene fluoride or chloride and copolymers of their derivatives, poly(chlorotrifluoroethylene), poly(ethylene-chlorotrifluoro-ethylene), poly(fluorinated ethylene-propylene), polyethylene oxide (PEO), oxymethylene linked PEO, PEO-polyphenylene oxide-PEO crosslinked with trifunctional urethane, poly(bis(methoxy-ethoxy-ethoxide))-phosphazene; a triol-type PEO crosslinked with difunctional urethane, poly((oligo)oxyethylene)methacrylate-co-alkali metal methacrylate, polyacrylonitrile, polymethylmethacrylate), polymethylacrylonitrile, polysiloxanes and their copolymers and derivatives, polyvinylidene fluoride or chloride and copolymers of their derivatives, poly(chlorotrifluoro-ethylene), poly(ethylene-chlorotrifluoroethylene), poly(fluorinated ethylene-propylene), acrylate-based polymer, other similar solvent-free polymers, combinations of the polymers either condensed or crosslinked to form a different polymer, and physical mixtures of the polymers, provided the first polymer is combinable with a lithium salt such that the ionic conductivity of the first polymer is enhanced. The second polymer (balance) is polyester, polypropylene, polyethylene naphthalate, polyvinylidene fluoride, polycarbonate, polyphenylene sulfide, polytetrafluoroethylene, or other polymer materials that possess stability and strength characteristics similar to the polymers. Preferred Property: The base polymer material is stable up to at least 150degreesC in the electrolyte. At least one of the polymer has a non-linear molecular structure and the electrolyte comprises a resilient, amorphous structure. The electrolyte is in the form of a 0.2-100 (preferably 0.2-3) microns thick film. The electrolyte has a resistance of not more than approximately 1 omega/cm2 when employed as a thin-film electrolyte in an electrochemical cell. EXAMPLE - Lithium imide (5 g) was mixed with IBOA (3 g), Ebecryl 230 (10 g), finely divided alumina (2.5 g), sulfide glass (6 g), in acetonitrile (40 ml). The polymer composite solution was cast on a glass plate. The acetonitrile was evaporated and the polymer thin layer was cured using ultraviolet light. The conductivity of the final polymer was 4x10-4 S/cm. Polymer/salt/filler/ionic conductor compositions yielded solid polymer electrolytes with favorable dimensional stability and great resiliency, and can be manufactured in ultra-thin film form thickness of 0.7-100 microns. The polymer electrolytes were non-tacky, pinhole free, flexible in nature, high strength, low resistance and demonstrated high ionic conductivity.