Nonaqueous electrolyte solution, secondary battery containing same, and electrical device

Patent metadata

Field	Value
Publication number	US-12456757-B2
Application number	US-202519033545-A
Country	US
Kind code	B2
Filing date	Jan 22, 2025
Priority date	Feb 8, 2023
Publication date	Oct 28, 2025
Grant date	Oct 28, 2025

Abstract

This application discloses a nonaqueous electrolyte solution, a secondary battery containing the nonaqueous electrolyte solution, and an electrical device. The nonaqueous electrolyte solution includes: a compound A including a saturated five-membered ring or six-membered ring and at least one fluorine-containing substituent, where the ring contains 1 or 2 oxygen atoms as ring atoms, and a ring carbon atom connected to the oxygen atom in the ring is not directly replaced by fluorine; and a compound B including a saturated five-membered ring or six-membered ring that contains 1 or 2 oxygen atoms as ring atoms, where at least one ring carbon atom connected to the oxygen atom in the ring is directly replaced by at least one fluorine atom.

First claim

What is claimed is:

1. A nonaqueous electrolyte solution, comprising:
a compound A, comprising a saturated five-membered ring or six-membered ring that contains 1 or 2 oxygen atoms as ring atoms, wherein the compound A comprises at least one fluorine-containing substituent, and a ring carbon atom connected to the oxygen atom in the five-membered ring or six-membered ring is not directly substituted with fluorine; and
a compound B, comprising a saturated five-membered ring or six-membered ring that contains 1 or 2 oxygen atoms as ring atoms, wherein at least one ring carbon atom connected to the oxygen atom in the five-membered ring or six-membered ring is directly substituted with at least one fluorine atom;
wherein the compound B comprises one of the following compounds:

2. The nonaqueous electrolyte solution according to claim 1 , wherein the compound A comprises 1 to 3 fluorine-containing substituents.

3. The nonaqueous electrolyte solution according to claim 1 , wherein, in the compound A, substituents on the five-membered ring or the six-membered ring comprise hydrogen, fluorine, —R, —OR, and unsubstituted or —R- or —OR-substituted phenyl, wherein R represents a C 1 to C 6 alkyl or a C 1 to C 6 fluoroalkyl.

4. The nonaqueous electrolyte solution according to claim 1 , wherein the compound A is represented by a chemical formula I:

wherein,
A 1 represents oxygen, a direct bond, or CHR 4 ;
A 2 represents oxygen, a direct bond, or CHR 5 ;
R 1 and R 2 each independently represent hydrogen, —R, —OR, or unsubstituted or —R- or —OR-substituted phenyl;
R 3 , R 4 , and R 5 each independently represent hydrogen, fluorine, —R, —OR, or unsubstituted or —R- or —OR-substituted phenyl, wherein
each R represents a C 1 to C 6 alkyl or a C 1 to C 6 fluoroalkyl;
A 1 and A 2 are not both direct bonds and are not both oxygen; and
when A 1 is oxygen, R 5 is not fluorine; when A 2 is oxygen, R 3 and R 4 are not fluorine;
R 1 , R 2 , R 3 , R 4 , and R 5 comprise at least 1 fluorine-containing substituent in total.

5. The nonaqueous electrolyte solution according to claim 1 , wherein the compound A comprises one of the following compounds:

6. The nonaqueous electrolyte solution according to claim 1 , wherein a mass ratio of the compound A to the compound B in the nonaqueous electrolyte solution ranges from 0.20 to 6.00.

7. The nonaqueous electrolyte solution according to claim 1 , wherein the nonaqueous electrolyte solution further comprises one or more lithium salts; further optionally, the lithium salt comprises one or more of lithium bis(fluorosulfonyl)imide, lithium hexafluorophosphate, lithium tetrafluoroborate, lithium hexafluoroarsenate, lithium bis(trifluoromethanesulfonyl)imide, lithium trifluoromethanesulfonate, lithium difluorophosphate, lithium dioxalatoborate, lithium difluoro(oxalato)borate, lithium difluorobis(oxalato)phosphate, lithium tetrafluoro(oxalato)phosphate, or a combination thereof.

8. The nonaqueous electrolyte solution according to claim 7 , wherein a concentration range of the lithium salt in the nonaqueous electrolyte solution is 0.3 to 6 mol/L.

9. The nonaqueous electrolyte solution according to claim 1 , wherein the nonaqueous electrolyte solution further comprises an additive C containing a phosphate ester group and an alkoxy chain, and a total number of carbon atoms in each alkoxy chain falls within a range of 1 to 20.

10. The nonaqueous electrolyte solution according to claim 9 , wherein a molecule of the additive C comprises a phosphate ester group and at least one of the following groups: a C 1 to C 4 alkyl, a C 1 to C 4 fluoroalkyl, a C 1 to C 4 ethoxyalkyl ether, a C 1 to C 4 ethoxy ethoxyalkyl ether, a C 1 to C 4 ethoxy fluoroalkyl ether, or a C 1 to C 4 ethoxy-ethoxy fluoroalkyl ether, wherein the fluoro in the C 1 to C 4 fluoroalkyl means monofluoro, difluoro, or trifluoro substitution by one, two, or three fluorine atoms, respectively, located at a terminal of a molecule of the additive C and not attached to a carbon atom directly adjacent to an oxygen atom.

11. The nonaqueous electrolyte solution according to claim 10 , wherein the additive C is represented by a chemical formula III:

wherein, n 1 , n 2 , and n 3 represent 0, 1, and 2 respectively, and n 1 , n 2 , and n 3 are not all 0;
R 16 , R 17 and R 18 each independently represent hydrogen, C 1 to C 4 alkyl, C 1 to C 4 monofluoroalkyl, C 1 to C 4 difluoroalkyl, or C 1 to C 4 trifluoroalkyl, wherein the fluoro in the C 1 to C 4 monofluoroalkyl, the C 1 to C 4 difluoroalkyl, or the C 1 to C 4 trifluoroalkyl means fluorine substitution by one, two, or three fluorine atoms, respectively, located at a terminal of a molecule of the additive C.

12. The nonaqueous electrolyte solution according to claim 11 , wherein the additive C comprises one of the following compounds:

Assignees

• Contemporary Amperex Technology Hong Kong Ltd

Inventors

• Wang Hansen
• Wan pan
• Liu Chengyong
• Hu Bobing
• Huang Shengyuan
• Zhang Rupeng

Classifications

• H01M2300/0037

  Mixture of solvents · CPC title

• H01M2300/0034

  Fluorinated solvents · CPC title

• H01M2004/027

  Negative electrodes · CPC title

• H01M2004/021

  Physical characteristics, e.g. porosity, surface area · CPC title

• H01M10/0568

  characterised by the solutes · CPC title