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

An electrolyte solution containing at least one compound (1) selected from the group consisting of a compound represented by the following formula (1-1) (wherein Rto Rare each individually a C1-C4 linear or branched alkyl group, and at least one selected from Rto Ris a C1-C4 branched alkyl group) and a compound represented by the following formula (1-2) (wherein Rto Rare each individually a C1-C4 linear or branched alkyl group, and at least one selected from Rto Ris a C1-C4 branched alkyl group). Also disclosed is an electrochemical device including the electrolyte solution, a lithium ion secondary battery including the electrolyte solution and a module including the electrochemical device or lithium ion secondary battery: