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

摘要

The present invention aims to provide an electrolyte solution for forming, for example, a secondary battery having excellent oxidation resistance and high-temperature storage characteristics; an electrochemical device such as a lithium-ion secondary battery that contains the electrolyte solution; and a module that contains the electrochemical device. The present invention provides an electrolyte solution containing a solvent and an electrolyte salt, wherein the solvent contains a fluorine-containing compound (A) represented by formula (1) shown below in an amount of 0.01 to 20% by mass, and a fluorine-containing compound (B) represented by formula (2) shown below in an amount of 10 to 80% by mass:
Rf1OCOOR  (1)
wherein Rf1 is a C1-C4 fluorine-containing alkyl group, and R is a C1-C4 non-fluorinated alkyl group, and
Rf2OCOORf3  (2)
wherein Rf2 and Rf3 are the same or different, and each is a C1-C4 fluorine-containing alkyl group.

主权项

1. An electrolyte solution comprising:
a solvent; and an electrolyte salt, the solvent containing a fluorine-containing compound (A) represented by formula (1) shown below in an amount of 0.01 to 20% by mass and a fluorine-containing compound (B) represented by formula (2) shown below in an amount of 20 to 80% by mass:
Rf1OCOOR  (1)wherein Rf1 is a C1-C4 fluorine-containing alkyl group, and R is a C1-C4 non-fluorinated alkyl group, and
Rf2OCOORf3  (2)wherein Rf2 and Rf3 are the same or different, and each is a C1-C4 fluorine-containing alkyl group,
wherein the fluorine-containing compound (A) is at least one compound selected from the group consisting of CF3CH2OCOOCH3, CF3CH2OCOOCH2CH3, CF3CF2CH2OCOOCH3, and CF3CF2CH2OCOOCH2CH3; and the fluorine-containing compound(B) is at least one compound selected from the group consisting of CF3CH2OCOOCH2CF3, CF2HCF2CH2OCOOCH2CF2CF2H, and (CF3)2CHOCOOCH(CF3)2.