Electrolyte solution, electrochemical device, lithium ion secondary battery and module

Abstract

An electrolyte solution containing a solvent. The solvent contains a compound (1) represented by the following formula (1), wherein Ra, Rb, Rc, and Rd are the same as or different from each other, and are each —H, —F, —CH3, or —CF3; at least one of Ra, Rb, Rc, or Rd is —F or —CF3; and at least one of Ra, Rb, Rc, or Rd is —CH3, and a compound (2) represented by the following formula (2), wherein Re is a C1-C5 linear or branched alkyl or alkoxy group optionally containing an ether bond; Rf is a C1-C5 linear or branched alkyl group optionally containing an ether bond; and at least one of Re or Rf contains a fluorine atom. 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.

Dependencies are inferred from the claim text.