Abstract: Techniques relating to an electrolyte having high ion conductivity and high strength are provided. The electrolyte includes an ionic liquid, an inorganic oxide, and a binder, wherein the binder is formed from raw materials that are a polycarbonate polyol and a polyisocyanate, and the binder includes, at an end, at least one functional group selected from the group consisting of a trialkoxysilyl group having 1 to 4 carbon atoms, an epoxy group, and an oxetanyl group.

Abstract: The production method is for an electrochemical device equipped with a pair of electrodes and an electrolyte located therebetween. The electrolyte with which the electrochemical device is provided is a gel-form body constituted by at least a matrix material and an electrolytic solution, contains cross-linkable reaction groups, and has a raised gel electrolyte hardening degree (hard gel electrolyte). The production method for the electrochemical device comprises an electrolyte hardening degree raising step of causing, with the gel electrolyte in a held state between the pair of electrodes, a crosslinking of the reaction groups to proceed, thereby causing the gel electrolyte hardening degree to be raised, while causing the electrolytic solution to seep out from the gel electrolyte as crosslinking proceeds.