ELECTROLYTE SOLUTION, ELECTROCHEMICAL DEVICE, LITHIUM ION SECONDARY BATTERY, AND MODULE

An electrolyte solution containing a compound (1) represented by the formula (1), (wherein Rand Rare each individually a substituent such as a C1-C7 alkyl group, and the substituent optionally contains at least one divalent to hexavalent hetero atom in a structure or optionally has a structure obtained by replacing at least one hydrogen atom by a fluorine atom or a C0-C7 functional group) and at least one compound (11) selected from compounds such as a compound represented by formula (11-1) (wherein Rand Rare the same as or different from each other and are each a hydrogen atom or the like, and Ris an alkyl group free from a fluorine atom or the like):