Secondary-battery current collector, secondary-battery cathode, secondary-battery anode, secondary battery and production method thereof

• US 10,033,045 B2
• Filed: 01/14/2014
• Issued: 07/24/2018
• Est. Priority Date: 02/10/2005
• Status: Active Grant

• Current Assignee: Shohoku Laminate Co., Ltd.
• Original Assignee: Showa Denko KK
• Inventors: Ohmori, Masahiro
• Primary Examiner(s): Mayes, Melvin C.
• Assistant Examiner(s): Forrest, Michael
• Application Number:
  US14/154,545
• Publication Number:
  US 20140127574A1
• Time in Patent Office: 1,652 Days
• CPC Class Codes: H01M 10/0525 Rocking-chair batteries, i.e. batteries with lithium insertion or intercalation in both electrodes; Lithium-ion batteries
• CPC Class Codes: H01M 4/0404 by coating on electrode collectors
• CPC Class Codes: H01M 4/1391 of electrodes based on mixed oxides or hydroxides, or on mixtures of oxides or hydroxides, e.g. LiCoOx
• CPC Class Codes: H01M 4/625 Carbon or graphite
• CPC Class Codes: H01M 4/661 Metal or alloys, e.g. alloy coatings H01M4/669 take precedence
• CPC Class Codes: H01M 4/667 in the form of layers, e.g. coatings
• CPC Class Codes: H01M 4/80 Porous plates, e.g. sintered carriers
• CPC Class Codes: Y02E 60/10 Energy storage using batteries

Abstract

A secondary-battery current collector comprising an aluminum foil and a film containing an ion-permeable compound and carbon fine particles formed thereon or a secondary-battery current collector comprising an aluminum foil, a film containing an ion-permeable compound and carbon fine particles formed thereon as the lower layer, and a film containing a binder, carbon fine particles and a cathodic electroactive material formed thereon as the upper layer, a production method of the same, and a secondary battery having the current collector are provided.

Claims

1. A secondary-battery current collector, comprising:

a foil comprising one of aluminum and copper; and

a film formed on the foil and consisting of carbon fine particles and a compound non-swelling in an organic solvent,

wherein the compound is a crosslinked polysaccharide polymer compound having a number average molecular weight of 50,000 or less, and the film has a thickness in a range of from 0.1 μ

m to 10 μ

m.

2. The secondary-battery current collector of claim 1, wherein the crosslinked polysaccharide polymer compound has a number average molecular weight in a range of from 22,000 to 40,000.

3. The secondary-battery current collector of claim 1, wherein the crosslinked polysaccharide polymer compound has a lithium-ion conductivity or a fluorine-ion conductivity of 1×

10<sup>−

2</sup> S/cm or more.

4. A secondary-battery electrode, comprising:

the secondary-battery current collector of claim 1; and

a film formed on the current collector and comprising a binder, carbon fine particles, and an electroactive material.

5. The secondary-battery electrode of claim 4, wherein the electroactive material is a cathodic electrode material comprising at least one of LiCoO₂, LiMn₂O₄, LiNiO₂, Li(Co_xMn_yNi_z)O₂, TiS₂, LiFePO₄, and LiMnPO₄.

6. The secondary-battery electrode of claim 4, wherein the electroactive material is an anodic electroactive material comprising graphite.

7. A secondary battery, comprising:

the secondary battery electrode of claim 4.

8. A mobile unit, comprising:

the secondary battery of claim 7.

9. A method of producing a secondary-battery current collector, comprising:

applying a composition consisting of carbon fine particles, a compound non-swelling in an organic solvent, and a solvent to a foil comprising one of aluminum and copper such that a film having a thickness in a range of from 0.1 μ

m to 10 μ

m is formed on the foil,

wherein the compound consists of a crosslinked polysaccharide polymer compound having a number average molecular weight of 50,000 or less.

11. The method of claim 9, wherein the crosslinked polysaccharide polymer compound has a number average molecular weight in a range of from 22,000 to 40,000.

13. The method of claim 11, wherein the solvent comprises N-methyl-2-pyrrolidone.

14. The method of claim 9, wherein the solvent is N-methyl-2-pyrrolidone.

10. A method of producing a secondary-battery electrode, comprising:

applying a composition consisting of carbon fine particles, a compound non-swelling in an organic solvent, and a solvent to a foil comprising one of aluminum and copper such that a film having a thickness in a range of from 0.1 μ

m to 10 μ

m is formed on the foil; and

coating, on the film, a dispersion comprising a solvent, a binder, carbon fine particles, and an electroactive material,

wherein the compound consists of a crosslinked polysaccharide polymer compound having a number average molecular weight of 50,000 or less.

12. The method of claim 10, wherein the crosslinked polysaccharide polymer compound has a number average molecular weight in a range of from 22,000 to 40,000.

15. The method of claim 10, wherein the solvent is N-methyl-2-pyrrolidone.