Secondary battery, battery pack, and vehicle

Patent metadata

Field	Value
Publication number	US-12266797-B2
Application number	US-202217650547-A
Country	US
Kind code	B2
Filing date	Feb 10, 2022
Priority date	Jul 16, 2021
Publication date	Apr 1, 2025
Grant date	Apr 1, 2025

Abstract

A secondary battery that includes: a positive electrode containing a positive electrode active material; a negative electrode; a separator arranged between the positive electrode and the negative electrode; and a first aqueous electrolyte held in at least the positive electrode. pH of the first aqueous electrolyte is more than 7. The positive electrode active material contains a lithium-containing compound that exhibits an average operating potential of less than 4.0 V based on lithium metal.

First claim

What is claimed is:

1. A secondary battery comprising:
a positive electrode that comprises a positive electrode active material;
a negative electrode;
a separator disposed between the positive electrode and the negative electrode;
a first aqueous electrolyte held in at least the positive electrode; and
a second aqueous electrolyte held in at least the negative electrode,
wherein a pH of the first aqueous electrolyte exceeds 7,
a pH of the second aqueous electrolyte is 8.0 or more, and
the positive electrode active material comprises a lithium-containing compound that exhibits an average operating potential of less than 4.0 V based on lithium metal.

2. The secondary battery according to claim 1 ,
wherein the pH of the first aqueous electrolyte is 8.0 or more.

3. The secondary battery according to claim 1 ,
wherein the pH of the first aqueous electrolyte is 13.0 or more.

4. The secondary battery according to claim 1 , wherein the lithium-containing compound is at least one selected from the group consisting of a lithium nickel composite oxide, a lithium cobalt composite oxide, a lithium nickel cobalt composite oxide, a lithium manganese cobalt composite oxide, a lithium phosphorus oxide having an olivine structure, a lithium nickel cobalt manganese composite oxide, and a lithium vanadium phosphorus oxide.

5. The secondary battery according to claim 1 ,
wherein the separator comprises a solid electrolyte membrane comprising a solid electrolyte that has lithium ion conductivity of 1×10 −10 S/cm or more at 25° C. and a porous sheet in which a permeability coefficient ranges from 1×10 −19 m 2 or more to less than 1×10 −15 m 2 .

6. The secondary battery according to claim 5 ,
wherein the separator comprises a composite solid electrolyte membrane in which the solid electrolyte membrane is stacked on at least one main surface of the porous sheet.

7. The secondary battery according to claim 6 ,
wherein a permeability coefficient of the composite solid electrolyte membrane ranges from 1×10 −19 m 2 or more to less than 1×10 −15 m 2 .

8. The secondary battery according to claim 1 ,
wherein the separator comprises a solid electrolyte membrane comprising a solid electrolyte that has lithium ion conductivity of 1×10 −10 S/cm or more at 25° C.

9. The secondary battery according to claim 1 ,
wherein the separator comprises a porous sheet in which a permeability coefficient ranges from 1×10 −19 m 2 or more to less than 1×10 −15 m 2 .

10. The secondary battery according to claim 1 , wherein the pH of the second aqueous electrolyte is 13.0 or more.

11. A battery pack comprising the secondary battery according to claim 1 .

12. The battery pack according to claim 11 , further comprising:
an external power distribution terminal; and
a protective circuit.

13. The battery pack according to claim 11 , comprising a plurality of the secondary battery, wherein the secondary batteries are electrically connected in series, in parallel, or in a combination of in series and in parallel.

14. A vehicle comprising the battery pack according to claim 13 .

15. The vehicle according to claim 14 , which comprises a mechanism configured to convert kinetic energy of the vehicle into regenerative energy.

16. The secondary battery according to claim 1 , wherein the first aqueous electrolyte comprises lithium ions, and a concentration of lithium ions in the first aqueous electrolyte is 6 mol/L or more.

Assignees

• Toshiba Kk

Inventors

• Seki Hayato
• Kuboki Takashi
• Matsuno Shinsuke

Classifications

• H01M2300/0094

  in the form of layered products, e.g. coatings · CPC title

• H01M2300/0002

  Aqueous electrolytes · CPC title

• H01M4/382

  Lithium (H01M4/405 takes precedence) · CPC title

• H01M2004/028

  Positive electrodes · CPC title

• H01M2004/027

  Negative electrodes · CPC title