Electrolytic solution, electrochemical device, lithium-ion secondary cell, and module

Patent metadata

Field	Value
Publication number	US-10243242-B2
Application number	US-201415103906-A
Country	US
Kind code	B2
Filing date	Dec 15, 2014
Priority date	Dec 20, 2013
Publication date	Mar 26, 2019
Grant date	Mar 26, 2019

Abstract

The present invention aims to provide an electrolyte solution that suppresses generation of gas. The electrolyte solution of the present invention includes a non-aqueous solvent (I) containing one or both of a fluorinated cyclic carbonate and a fluorinated acyclic carbonate; an electrolyte salt (II); and a compound (III) represented by the following formula (1):

wherein R 1 is a C1-C20 linear or branched alkenyl or alkyl group or a C3-C20 alkyl group having a cyclic structure; m is 0 or 1; R 2 is a C1-C20 linear or branched alkylene group or a C3-C20 alkylene group having a cyclic structure, R 1 and R 2 each may have an oxygen atom between carbon atoms if R 1 and R 2 each have two or more carbon atoms, but the oxygen atom is not adjacent to another oxygen atom.

First claim

The invention claimed is:

1. An electrolyte solution comprising
a non-aqueous solvent (I) containing one or both of a fluorinated cyclic carbonate and a fluorinated acyclic carbonate,
an electrolyte salt (II); and
a compound (III) represented by the following formula (1):

wherein R 1 is a C1-C20 linear or branched alkyl group or a C3-C20 alkyl group having a cyclic structure; m is 0; R 2 is a C1-C20 linear or branched alkylene group or a C3-C20 alkylene group having a cyclic structure, R 1 and R 2 each may have an oxygen atom between carbon atoms if R 1 and R 2 each have two or more carbon atoms, but the oxygen atom is not adjacent to another oxygen atom,
wherein the compound (III) is present in an amount of 0.01 to 12 mass % in the electrolyte solution.

2. The electrolyte solution according to claim 1 ,
wherein R 1 is —CH 3 , —CH 2 —CH 3 , —CH 2 —CH 2 —CH 3 , or —CH(CH 3 )—CH 3 .

3. The electrolyte solution according to claim 1 ,
wherein R 2 is —CH 2 —, —CH 2 —CH 2 —, or —CH 2 —CH 2 —CH 2 —.

4. The electrolyte solution according to claim 1 ,
wherein the non-aqueous solvent (I) at least contains a fluorinated acyclic carbonate.

5. An electrochemical device comprising the electrolyte solution according to claim 1 .

6. A lithium ion secondary battery comprising the electrolyte solution according to claim 1 .

7. A module comprising the lithium ion secondary battery according to claim 6 .

8. The electrolyte solution according to claim 1 , wherein the compound (III) is present in an amount of 0.01 to 10 mass % in the electrolyte solution.

9. The electrolyte solution according to claim 1 , wherein the non-aqueous solvent (I) contains one or both of a fluorinated cyclic carbonate and a fluorinated acyclic carbonate, and wherein the fluorinated cyclic carbonate is present in an amount of 60 vol % or less of the non-aqueous solvent (I), and the fluorinated acyclic carbonate is present in an amount of 70 vol % or less of the non-aqueous solvent (I).

10. An electrolyte solution according to claim 1 ,
wherein the fluorinated cyclic carbonate is at least one compound selected from the group consisting of compounds represented by the following formulas (2) to (6):

11. The electrolyte solution according to claim 1 , wherein the fluorinated acyclic carbonate is at least one compound selected from the group consisting of (2,2,2-trifluoroethyl)methyl carbonate and (2,2,3,3-tetrafluoropropyl)methyl carbonate.

Assignees

• Daikin Ind Ltd

Inventors

• Okada Michiaki
• Tani Akinori
• Kinoshita Shinichi
• Arima Hiroyuki
• SHIMADA Tomo
• Taeda Mayuko

Classifications

• H01M50/417

  Polyolefins · CPC title

• H01M50/491

  Porosity · CPC title

• H01M50/489

  Separators, membranes, diaphragms or spacing elements inside the cells, characterised by their physical properties, e.g. swelling degree, hydrophilicity or shut down properties · CPC title

• H01M2300/0034

  Fluorinated solvents · CPC title

• H01M4/622

  being polymers · CPC title