Method of producing lithium-ion secondary battery, lithium-ion secondary battery, and method of using zwitterionic compound

Patent metadata

Field	Value
Publication number	US-11961964-B2
Application number	US-201816175995-A
Country	US
Kind code	B2
Filing date	Oct 31, 2018
Priority date	Oct 31, 2017
Publication date	Apr 16, 2024
Grant date	Apr 16, 2024

Abstract

A method of producing a lithium-ion secondary battery includes the following (α) and (β): (α) preparing a lithium-ion secondary battery, the lithium-ion secondary battery including at least a positive electrode, a negative electrode, and an electrolyte solution; and (β) adding a zwitterionic compound to the electrolyte solution. The negative electrode includes at least a negative electrode active material and a film. The film is formed on a surface of the negative electrode active material. The film contains a lithium compound. The zwitterionic compound contains a phosphonium cation or an ammonium cation and a carboxylate anion in one molecule.

First claim

What is claimed is:

1. A method of producing a lithium-ion secondary battery, comprising:
preparing a lithium-ion secondary battery, the lithium-ion secondary battery comprising at least a positive electrode, a negative electrode, and an electrolyte solution, the electrolyte solution of the prepared lithium-ion secondary battery comprising a solvent and a lithium salt; and
adding a zwitterionic compound to the electrolyte solution of the prepared lithium-ion secondary battery,
the negative electrode of the prepared lithium-ion secondary battery including at least a negative electrode active material and a solid electrolyte interface (SEI) film,
the SEI film being formed on a surface of the negative electrode active material prior to adding the zwitterionic compound to the electrolyte solution,
the film containing a lithium compound,
the zwitterionic compound containing a phosphonium cation and a carboxylate anion in one molecule,
wherein the method includes determining an amount of the zwitterionic compound to be added to the electrolyte solution of the lithium-ion secondary battery a capacity loss of the battery caused by the SEI film.

2. The method of producing a lithium-ion secondary battery according to claim 1 , wherein an amount of the zwitterionic compound in the electrolyte solution is 0.01 to 0.1 mol/l.

3. The method of producing a lithium-ion secondary battery according to claim 1 , wherein an amount of the lithium salt in the electrolyte solution of the prepared lithium-ion secondary battery is 0.5 to 2 mol/l.

4. The method of producing a lithium-ion secondary battery according to claim 1 , wherein an amount of the zwitterionic compound in the electrolyte solution is 0.01 to 0.1 mol/l, and
an amount of the lithium salt in the electrolyte solution of the prepared lithium-ion secondary battery is 0.5 to 2 mol/l.

5. The method of producing a lithium-ion secondary battery according to claim 1 , wherein the zwitterionic compound is be represented by the following formula (I):

where X represents a phosphorus atom (P); R 1 represents a C 1-10 alkylene group, a C 1-10 substituent containing an ether bond, or an aryl group; each of R 2 , R 3 , and R 4 independently represents a hydrogen atom, a C 1-10 alkyl group, a C 1-10 substituent containing an ether bond, or an aryl group; and two or more of R 1 , R 2 , R 3 , and R 4 may be bonded to each other and form a ring compound together with X.

6. The method of producing a lithium-ion secondary battery according to claim 1 , wherein the zwitterionic compound is be represented by the following formula (II):

where X represents P; R 5 represents a C 1-8 alkylene group; and each of R 6 , R 7 , and R 8 independently represents a C 1-8 alkyl group.

7. The method of producing a lithium-ion secondary battery according to claim 1 , wherein the zwitterionic compound is be represented by the following formula (III):

where X represents P; and each of R 9 , R 10 and R 11 independently represents a C 1-6 alkyl group.

8. The method of producing a lithium-ion secondary battery according to claim 1 , wherein the zwitterionic compound is be represented by the following formula (IV):
(CH 3 CH 2 CH 2 CH 2 ) 3 P + CH 2 CO 2 −   (IV).

9. A lithium-ion secondary battery comprising at least a positive electrode, a negative electrode, and an electrolyte solution,
the negative electrode including at least a negative electrode active material and a solid electrolyte interface (SEI) film, the SEI film being formed on a surface of the negative electrode active material, the film containing a lithium compound,
the electrolyte solution containing at least a solvent, a lithium salt, and a zwitterionic compound, the solvent not containing a salt,
the zwitterionic compound containing a phosphonium cation and a carboxylate anion in one molecule,
an amount of the zwitterionic compound in the electrolyte solution is 0.01 to 0.1 mol/L.

10. The lithium-ion secondary battery according to claim 9 , wherein an amount of the lithium salt in the electrolyte solution is 0.5 to 2 mol/l.

11. The lithium-ion secondary battery according to claim 9 ,
wherein an amount of the lithium salt in the electrolyte solution is 0.5 to 2 mol/l.

12. A method of using a zwitterionic compound to restore capacity of a lithium-ion secondary battery, comprising:
identifying a battery as having a deteriorated capacity, wherein the battery having the deteriorated capacity comprises at least a positive electrode, a negative electrode, and an electrolyte solution, the electrolyte solution comprising a solvent and a lithium salt, and the negative electrode including at least a negative electrode active material and a solid electrolyte interface (SEI) film formed on a surface of the negative electrode active material;
determining a capacity loss of the battery having the deteriorated capacity;
selecting an amount of a zwitterionic compound to add to the electrolyte solution of the lithium-ion secondary battery having the deteriorated capacity based on the capacity loss;
preparing the zwitterionic compound; and
restoring capacity of the lithium-ion secondary battery having the deteriorated capacity by adding the zwitterionic compound to the electrolyte solution of the lithium-ion secondary battery having the deteriorated capacity and the SEI film on the surface of the negative electrode active material,
wherein the zwitterionic compound contains a phosphonium cation and a carboxylate anion in one molecule, and
the deteriorated capacity represents a capacity being lower than an initial capacity of the lithium-ion secondary battery.

13. The method of using a zwitterionic compound according to claim 12 , wherein an amount of the zwitterionic compound in the electrolyte solution is 0.01 to 0.1 mol/l.

14. The method of using a zwitterionic compound according to claim 12 , wherein an amount of the lithium salt in the electrolyte solution is 0.5 to 2 mol/l.

15. The method of using a zwitterionic compound according to claim 12 , wherein an amount of the zwitterionic compound in the electrolyte solution is 0.01 to 0.1 mol/l, and
an amount of the lithium salt in the electrolyte solution is 0.5 to 2 mol/l.

16. The method of using a zwitterionic compound according to claim 12 , wherein the zwitterionic compound is be represented by the following formula (I):

where X represents a phosphorus atom (P); R 1 represents a C 1-10 alkylene group, a C 1-10 substituent containing an ether bond, or an aryl group; each of R 2 , R 3 , and R 4 independently represents a hydrogen atom, a C 1-10 alkyl group, a C 1-10 substituent containing an ether bond, or an aryl group; and two or more of R 1 , R 2 , R 3 , and R 4 may be bonded to each other and form a ring compound together with X.

17. The method of using a zwitterionic compound according to claim 12 , wherein the zwitterionic compound is be represented by the following formula (II):

where X represents P; R 5 represents a C 1-8 alkylene group; and each of R 6 , R 7 , and R 8 i

Assignees

• Toyota Motor Co Ltd
• Sophia School Corp

Inventors

• Okayama Shinobu
• Yamaguchi Hiroyuki
• Kikuchi Kyoko
• Fujita Masahiro

Classifications

• H01M10/0567 Primary

  characterised by the additives · CPC title

• H01M4/13

  Electrodes for accumulators with non-aqueous electrolyte, e.g. for lithium-accumulators; Processes of manufacture thereof · CPC title

• H01M4/366

  as layered products · CPC title

• H01M10/0525

  Rocking-chair batteries, i.e. batteries with lithium insertion or intercalation in both electrodes; Lithium-ion batteries · CPC title

• H01M10/056

  characterised by the materials used as electrolytes, e.g. mixed inorganic/organic electrolytes · CPC title