Abstract: Gel electrolytes for electrochromic and electrochemical devices wherein in one embodiment polymeric gelling agents/atactic or syndiotactic, and isotactic PMMA, and a lithium salt in a suitable solvent are dissolved at a temperature above the gelation point and cooled to form a gel electrolyte. In another embodiment a preelectrolyte film is formed by casting a solution of a mixture of stereocomplexed PMMA with a plasticizer (a complexing low molecular weight polar solvent) in a non-complexing volatile solvent (e.i., CClH3), followed by the activation of the film in a liquid electrolyte which includes a lithium salt and low molecular weight complexing solvents to form the completed gel electrolyte.