Electrolyte solution for electrochemical device and electrochemical device using same

Abstract

The present invention has for its object to provide an electrolyte solution which can dramatically suppress the time degradation in performance of an electrochemical device, especially an electrochemical capacitor. The present invention relates to an electrolyte solution for electrochemical device which comprises an imidazolium salt (A) represented by the general formula (1) as a main component, wherein the content of the imidazolium salt (B) represented by the general formula (2) is not more than 15% by weight to the total weight of the imidazolium salt (A) and imidazolium salt (B); (in the formula, R1, R2 and R3 may be the same or different and each represents an alkyl group containing 1 to 3 carbon atoms; R4 and R5 may be the same or different and each represents an hydrogen atom or an alkyl group containing 1 to 3 carbon atoms; and X− represents a counter anion) (in the formula, R1, R3, R4, R5 and X− are the same as the definition for the general formula (1)).

Dependencies are inferred from the claim text.