Copper foil having excellent heat resistance property

Patent metadata

Field	Value
Publication number	US-12170375-B2
Application number	US-201916668735-A
Country	US
Kind code	B2
Filing date	Oct 30, 2019
Priority date	Oct 30, 2019
Publication date	Dec 17, 2024
Grant date	Dec 17, 2024

Abstract

Electrodeposited copper foils are described having improved thermal properties. The copper foils include a drum side and deposited side where both sides have a roughness Rz lower than 2 μm and wherein, when the electrodeposited copper foil is subjected to a thermal gravimetric analysis (TGA), the electrodeposited copper foil exhibits a primary weight increase of 105 wt. % when a primary temperature (T 105 wt % ) is reached during the TGA, wherein the T 105 wt % is in a range of 350° C. to 501° C. The TGA characterization comprises heating at a rate of 5° C./min and an air flow at a rate of 95 mL/min. Ultrasonic welding of the copper foils to nickel foils provides an excellent weld with low detachment providing a good mechanical and electrical contact for applications such as in lithium-ion secondary batteries.

First claim

We claim:

1. An electrodeposited copper foil comprising a drum side and a deposited side;
wherein each of the drum side and the deposited side of the electrodeposited copper foil have a ten-point average roughness, Rz, in the range of 1.0 μm to less than or equal to 2 μm, and each of the drum side and the deposited side of the electrodeposited copper foil further comprise a chromium coating, wherein the electrodeposited copper foil exhibits a primary weight increase of 105 wt. %, when a primary temperature (T 105 wt % ) is reached during thermal gravimetric analysis (TGA), wherein the primary temperature (T 105 wt % ), is in a range of 350° C. to 501° C., and
wherein the TGA comprises heating the electrodeposited copper foil at a rate of 5° C./min and an air flow at a rate of 95 mL/min.

2. The electrodeposited copper foil according to claim 1 , wherein the electrodeposited copper foil exhibits a secondary weight increase of 100.1 wt. % when a secondary temperature (T 100.1 wt % ) is reached during the TGA, wherein the T 100.1wt % is in a range of 130° C. to 230° C.

3. The electrodeposited copper foil according to claim 2 , wherein the T 100.1 wt % is in a range of 130° C. to 200° C.

4. The electrodeposited copper foil according to claim 1 , wherein the electrodeposited copper foil exhibits an onset temperature (T onset ) during the TGA, wherein the T onset is in a range of 300° C. to 430° C.

5. The electrodeposited copper foil according to claim 4 , wherein the T onset is in a range of 320° C. to 430° C.

6. The electrodeposited copper foil according to claim 4 , wherein the electrodeposited copper foil exhibits a Weight Increase Rate (WIR) in a range of 0.068 to 0.313 wt %/° C., wherein the WIR is defined by Formula I:

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I
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R

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wt
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I
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7. The electrodeposited copper foil according to claim 6 wherein the WIR is in a range of 0.068 to 0.25 wt. %/° C.

8. The electrodeposited copper foil according to claim 6 , wherein the WIR is in a range of 0.068 to 0.20 wt. %/° C.

9. A secondary lithium-ion battery comprising the electrodeposited copper foil of claim 1 and an active material coated on the electrodeposited copper foil, wherein the electrodeposited copper foil is welded to a nickel connecting tab.

Assignees

• Chang Chun Petrochemical Co Ltd

Inventors

• Lai Yao-Sheng
• Chou Jui-Chang

Classifications

• H01M10/0525

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

• H01M4/667

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

• H01M4/13

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

• C25D3/38

  of copper · CPC title

• C25D3/04

  of chromium · CPC title