Electrolytic copper foil, negative electrode for lithium ion secondary battery, and lithium ion secondary battery

Patent metadata

Field	Value
Publication number	US-10050277-B2
Application number	US-201314425346-A
Country	US
Kind code	B2
Filing date	Jun 25, 2013
Priority date	Jun 27, 2012
Publication date	Aug 14, 2018
Grant date	Aug 14, 2018

Abstract

Provided are an electrodeposited copper foil, a negative electrode that is for a lithium ion secondary battery, and a lithium ion secondary battery into which the electrode is incorporated. The electrodeposited copper foil exhibits good electrical conductivity and superior tensile strength, with no significant decline in tensile strength exhibited even after one hour of heating at 300° C. The negative electrode has heightened cycle properties due to the use of the electrodeposited copper foil as a current collector. Using x-ray diffraction, in the electrodeposited copper foil, in normal conditions, the diffraction intensity (I)<220> in the <220> orientation, the diffraction intensity (I)<200> in the <200> orientation, and the diffraction intensity (I)<111> in the <111> orientation, satisfy the following formula (1):

I <220>/{ I <220>+ I <200>+ I <111>}>0.13  (1).

First claim

What is claimed is:

1. An electrodeposited copper foil for a lithium ion secondary battery, wherein, using x-ray diffraction, in normal conditions, a diffraction intensity I<220> thereof in a <220> orientation, a diffraction intensity I<200> thereof in a <200> orientation, and a diffraction intensity I<111> thereof in a <111> orientation, satisfy the following formula (1):
I< 220>/{ I< 220>+ I< 200>+ I< 111>}≥0.30  (1)

in normal conditions, a tensile strength thereof is 450 MPa or greater, and
in normal conditions, electrical conductivity thereof is 80% IACS or greater measured right after the electrodeposited copper foil is manufactured with an electrolytic method.

2. The electrodeposited copper foil for a lithium ion secondary battery according to claim 1 , wherein, in normal conditions, a tensile strength thereof is 500 MPa or greater.

3. The electrodeposited copper foil for a lithium ion secondary battery according to claim 1 , wherein a tensile strength thereof after a heating process of one hour at 300° C. is 400 MPa or greater.

4. The electrodeposited copper foil for a lithium ion secondary battery according to claim 1 , wherein electrical conductivity thereof after a heating process of one hour at 300° C. is 85% IACS or greater.

5. The electrodeposited copper foil for a lithium ion secondary battery according to claim 2 , wherein a tensile strength thereof after a heating process of one hour at 300° C. is 400 MPa or greater.

6. The electrodeposited copper foil for a lithium ion secondary battery according to claim 2 , wherein electrical conductivity thereof after a heating process of one hour at 300° C. is 85% IACS or greater.

7. An electrodeposited copper foil for a lithium ion secondary battery, wherein, using x-ray diffraction, in normal conditions, a diffraction intensity I<220> thereof in a <220> orientation, a diffraction intensity I<200> thereof in a <200> orientation, and a diffraction intensity I<111> thereof in a <111> orientation, satisfy the following formula (2):
0.65> I< 220>/{ I< 220>+ I< 200>+ I< 111>}>≥0.30  (2)

in normal conditions, a tensile strength thereof is 450 MPa or greater, and
in normal conditions, electrical conductivity thereof is 80% IACS or greater measured right after the electrodeposited copper foil is manufactured with an electrolytic method.

8. The electrodeposited copper foil for a lithium ion secondary battery according to claim 7 , wherein, in normal conditions, a tensile strength thereof is 500 MPa or greater.

9. The electrodeposited copper foil for a lithium ion secondary battery according to claim 7 , wherein a tensile strength thereof after a heating process of one hour at 300° C. is 400 MPa or greater.

10. The electrodeposited copper foil for a lithium ion secondary battery according to claim 7 , wherein electrical conductivity thereof after a heating process of one hour at 300° C. is 85% IACS or greater.

Assignees

• Furukawa Electric Co Ltd

Inventors

• Shinozaki Jun
• Fujisawa Kimiko
• Tachibana Akira

Classifications

• H01M2220/30

  Batteries in portable systems, e.g. mobile phone, laptop · CPC title

• H01M10/0525

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

• C25D3/38

  of copper · CPC title

• Y10T428/12431

  Foil or filament smaller than 6 mils · CPC title

• Y10T428/24917

  including metal layer · CPC title