ELECTROLYTE SOLUTION FOR ELECTROCHEMICAL DEVICE AND ELECTROCHEMICAL DEVICE USING SAME

摘要

Disclosed is an electrolyte solution which enables to dramatically improve performance deterioration of an electrochemical device, particularly of an electrochemical capacitor over time. Specifically disclosed is an electrolyte solution for electrochemical devices mainly containing an imidazolium salt (A) represented by the general formula (1) below. This electrolyte solution for electrochemical devices is characterized in that the content of an imidazolium salt (B) represented by the general formula (2) below is not more than 15% by weight relative to the total weight of the imidazolium salt (A) and the imidazolium salt (B). [Chemical formula 1] (1) (In the formula, R1, R2 and R3 independently represent an alkyl group having 1-3 carbon atoms; R4 and R5 independently represent a hydrogen atom or an alkyl group having 1-3 carbon atoms; and X- represents a counter anion.) [Chemical formula 2] (2) (In the formula, R1, R3, R4, R5 and X- are as defined in the general formula (1).)