Electrode for battery, battery having electrode and method for manufacturing electrode and battery having electrode

Patent metadata

Field	Value
Publication number	US-12463223-B2
Application number	US-202318126123-A
Country	US
Kind code	B2
Filing date	Mar 24, 2023
Priority date	May 25, 2016
Publication date	Nov 4, 2025
Grant date	Nov 4, 2025

Abstract

Provided is an electrode for a battery which effectively suppress a short circuit between a positive electrode and a negative electrode at high temperature of the battery.The electrode includes a current collector 110, an active material layer 111 formed on at least one side of the current collector 110 and an insulating layer 112 formed on the surface of the active material layer 111. The electrode was formed so that peeling occurs between the current collector 110 and the active material layer 111 and the peeling strength was 10 mN/mm or more when a 90° peeling test was performed at a peeling rate of 100/min.

First claim

The invention claimed is:

1. A battery comprising:
at least one positive electrode;
a separator; and
at least one negative electrode disposed to face the positive electrode via the separator,
wherein at least one of the positive electrode and the negative electrode comprises:
a current collector,
an active material layer formed on at least one surface of the current collector, and
an insulating layer adhered to a surface of the active material layer,

wherein a peeling strength between the active material layer and the insulating layer is higher than a peeling strength between the current collector and the active material layer,
peeling occurs between the current collector and the active material layer and a peeling strength thereof is 11 mN/mm or more in a 90° peeling test at a peeling rate of 100 mm/min, and
the insulating layer includes non-conductive particles and a binder, a mass percentage of the binder in the insulating layer is 10 to 20 mass %, the binder adhering the insulating layer to the surface of the active material layer, and
wherein neither the positive electrode, nor the negative electrode, nor the insulating layer are adhered to the separator.

2. The battery according to claim 1 , wherein the current collector is a positive electrode current collector, the active material layer is a positive electrode active material layer, and the binder in the insulating layer is polyvinylidene fluoride.

3. The battery according to claim 1 , wherein the positive electrode active material layer includes a positive electrode active material and a positive electrode binder, and the amount of the positive electrode binder is 2 to 15 parts by mass relative to 100 parts by mass of the positive electrode active material.

4. The battery according to claim 1 , wherein the current collector is a negative electrode current collector, the active material layer is a negative electrode active material layer, and the insulating layer includes at least one of polyimide, polyacrylic acid and polyvinylidene fluoride as the binder.

5. The battery according to claim 4 , wherein the binder for the insulating layer is polyimide.

6. The battery according to claim 4 , wherein the negative electrode active material layer includes a negative electrode active material and a negative electrode binder, and the mass percentage of the negative electrode binder in the active material layer is 2 mass % or more.

7. A method for manufacturing a battery, the method comprising;
preparing at least one positive electrode,
preparing a separator,
preparing at least one negative electrode, and
disposing the positive electrode and the negative electrode facing each other via the separator,
wherein the step of preparing the positive electrode comprises:
forming a positive electrode active material layer on at least one surface of a current collector, and
forming an insulating layer such that the insulating layer is finally adhered on a surface of the positive electrode active material layer,

wherein the step of forming the positive electrode active material layer comprises:
applying a mixture for the positive electrode active material layer in which a positive electrode active material and a positive electrode binder are dispersed in a solvent, and drying the mixture for the positive electrode active material layer after the mixture is applied, and

wherein the step of forming the insulating layer comprises:
applying a mixture for the insulating layer, in which an insulating material and a binder are dispersed in a solvent, onto the surface of the positive electrode active material layer, and drying the mixture for the insulating layer after the mixture is applied, and

wherein a peeling strength between the positive electrode active material layer and the insulating layer is higher than a peeling strength between the current collector and the positive electrode active material layer,
peeling occurs between the current collector and the positive electrode active material layer and a peeling strength thereof is 11 mN/mm or more in a 90° peeling test at a peeling rate of 100 mm/min, and
a mass percentage of the binder in the insulating layer is 10 to 20 mass %, the binder adhering the insulating layer to the surface of the positive electrode active material layer, and
wherein neither the positive electrode, nor the negative electrode, nor the insulating layer are adhered to the separator.

8. The method for manufacturing the battery according to claim 7 , wherein the step of forming the positive electrode active material layer further comprises compression-molding the mixture for the insulating layer after the mixture is dried.

9. The method for manufacturing the battery according to claim 8 ,
wherein the step of applying the mixture for the positive electrode active material layer,
the step of drying the mixture for the positive electrode active material layer,
the step of applying the mixture for the insulating layer onto the surface of the positive electrode active material layer,
the step of drying the mixture for the insulating layer and
the step of compression-molding the mixture for the insulating layer are carried out in this order.

10. The method for manufacturing the battery according to claim 7 , wherein the amount of the positive electrode binder is 2 to 15 parts by mass relative to 100 parts by mass of the positive electrode active material.

11. A method for manufacturing a battery, the method comprising;
preparing a separator,
preparing at least one positive electrode and at least one negative electrode, and
disposing the positive electrode and the negative electrode facing each other via the separator,
wherein the step of preparing the positive electrode comprises
forming a positive electrode active material layer on at least one surface of a current collector, and
forming an insulating layer such that the insulating layer is finally adhered on a surface of the positive electrode active material layer,

wherein the step of forming the negative electrode active material layer comprises:
applying a mixture for the negative electrode active material layer in which a negative electrode active material and a negative electrode binder are dispersed in a solvent, and drying the mixture for the negative electrode active material layer after the mixture is applied, and

the step of forming the insulating layer comprises:
applying a mixture for the insulating layer, in which an insulating material and a binder are dispersed in a solvent, onto the surface of the negative electrode active material layer, and drying the mixture for the insulating layer after the mixture is applied, and

wherein a peeling strength between the negative electrode active material layer and the insulating layer is higher than a peeling strength between the current collector and the negative electrode active material layer,
peeling occurs between the current collector and the negative electrode active material layer and a peeling strength thereof is 11 mN/mm or more in a 90° peeling test at a peeling rate of 100 mm/min, and
a mass percentage of the binder in the insulating layer is 10 to 20 mass %, the binder adhering the insulating layer to the surface of the negative electrode active material layer, and
wherein neither the positive electrode, the negative electrode, nor the insulating layer are adhered to the separator.

12. The method for manufacturing the battery according to claim 11 , wherein the step of forming the negative electrode active material layer further comprises compression-molding the mixture for the negative electrode active material layer after the mixture for

Assignees

• Nec Corp

Inventors

• Yoshida Noboru
• Otohata Makihiro
• Sudo Shinya

Classifications

• H01M4/131 Primary

  Electrodes based on mixed oxides or hydroxides, or on mixtures of oxides or hydroxides, e.g. LiCoOx · CPC title

• H01M50/46

  Separators, membranes or diaphragms characterised by their combination with electrodes · CPC title

• H01M2004/028

  Positive electrodes · CPC title

• H01M2004/027

  Negative electrodes · CPC title

• H01M2004/021

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