Copper foil and methods of use

• US 9,707,738 B1
• Filed: 01/14/2016
• Issued: 07/18/2017
• Est. Priority Date: 01/14/2016
• Status: Active Grant

• Current Assignee: Chang CHUN Petrochemical Company Limited (C.C.P. Contact Probes Co., Ltd.)
• Original Assignee: Chang CHUN Petrochemical Company Limited (C.C.P. Contact Probes Co., Ltd.)
• Inventors: Tseng, Shih-Cheng, Juo, Tsang-Jin, Cheng, Kuei-Sen
• Primary Examiner(s): Sample, David
• Assistant Examiner(s): Jordan, Nicholas W
• Application Number:
  US14/995,911
• Publication Number:
  US 20170203544A1
• Time in Patent Office: 551 Days
• Field of Search: None
• CPC Class Codes: B32B 15/01 all layers being exclusively metallic making layered metal workpieces by pressure cladding B23K20/22; making coatings with a metallic material characterised by its composition C23C30/00
• CPC Class Codes: B32B 2311/12 Copper
• CPC Class Codes: B32B 2311/22 Nickel or cobalt
• CPC Class Codes: B32B 2457/00 Electrical equipment
• CPC Class Codes: B32B 37/10 characterised by the pressing technique, e.g. using action of vacuum or fluid pressure
• CPC Class Codes: B32B 37/1284 Application of adhesive
• CPC Class Codes: B32B 37/16 with all layers existing as coherent layers before laminating
• CPC Class Codes: C25D 1/04 Wires; Strips; Foils
• CPC Class Codes: C25D 3/12 of nickel or cobalt
• CPC Class Codes: C25D 3/38 of copper
• CPC Class Codes: C25D 5/14 two or more layers being of nickel or chromium, e.g. duplex or triplex layers
• CPC Class Codes: C25D 5/605 Surface topography of the layers, e.g. rough, dendritic or nodular layers
• CPC Class Codes: C25D 5/611 Smooth layers
• CPC Class Codes: C25D 7/0614 Strips or foils
• CPC Class Codes: C25D 7/0621 In horizontal cells
• CPC Class Codes: H01C 1/1406 Terminals or electrodes formed on resistive elements having positive temperature coefficient
• CPC Class Codes: H01C 17/28 adapted for applying terminals
• CPC Class Codes: H01C 7/008 Thermistors H01C7/02 - H01C7/06 take precedence
• CPC Class Codes: H01C 7/027 consisting of conducting or semi-conducting material dispersed in a non-conductive organic material
• CPC Class Codes: H05K 1/09 Use of materials for the conductive, e.g. metallic pattern
• CPC Class Codes: H05K 2201/0355 : Metal foils
• CPC Class Codes: H05K 2203/0307 : Providing micro- or nanometer scale roughness on a metal surface, e.g. by plating of nodules or dendrites

Abstract

A copper foil having a matte side with nickel plated thereon in an amount of nickel in the range of 100,000-300,000 μs/dm². The plated copper foils have particular utility in Positive Temperature Coefficient (PTC) devices. The plated copper foils have a surface hardness of from 50 to 200, a tensile strength greater than 45 kg/mm² and a shiny side surface roughness (Rz) not exceeding 2.0 μm. The surface roughness of the matte side of the copper foil is in the range of 6 to 10 μm. Copper nodules are present on the matte side of the copper foil between the copper foil and the nickel plating. Methods of producing the copper foil and PTC devices incorporating the copper foil are described.

Claims

1. A nickel-plated copper foil comprising:

an electrodeposited foil of copper, the foil having a shiny side and a matte side;

the matte side of the copper foil having copper nodules in direct contact with the matte side of the copper foil;

a nickel plating over the matte side of the copper foil and the copper nodules in direct contact with the copper foil; and

,

nickel nodules in direct contact with said nickel plating;

wherein the nickel content on the matte side of the copper foil being in the range of 100,000-300,000 μ

g/dm².

2. The nickel-plated copper foil of claim 1, wherein the shiny side of the copper foil has a surface roughness (Rz) of less than 2.0 μ

m.

3. The nickel-plated copper foil of claim 1, wherein the surface hardness of the shiny side of the copper foil is from 50 to 200.

4. The nickel-plated copper foil of claim 1, wherein the matte side of the copper foil has a surface roughness (Rz) in the range of 6-10 μ

m.

5. The nickel-plated copper foil of claim 1, further comprising nickel on the shiny side of the copper foil;

wherein the nickel content on the shiny side of the copper foil being in the range of 10,000-80,000 μ

g/dm².

6. The nickel-plated copper foil of claim 1, wherein the tensile strength of the copper foil is at least 45 kg/mm².

7. The nickel-plated foil of claim 1, wherein the color L* of the matte side of the copper foil is from 30 to 60.

8. A Positive Temperature Coefficient (PTC) device comprising the nickel-plated copper foil of claim 1.

9. The Positive Temperature Coefficient (PTC) device of claim 8, further comprising an electrically insulating polymer having electrically conductive filler in the polymer.

10. The Positive Temperature Coefficient (PTC) device of claim 9, further comprising a second nickel-plated copper foil positioned with the polymer and electrically conductive filler between the second nickel-plated copper foil and the matte side of the first nickel-plated copper foil.

11. The Positive Temperature Coefficient (PTC) device of claim 10, wherein the electrode is in a shape selected from the group consisting of an annular ring, a disc, a strap and a radial-leaded device.

12. The Positive Temperature Coefficient (PTC) device of claim 10, wherein the Positive Temperature Coefficient (PTC) device is a surface mount device.

13. A method of manufacturing a Positive Temperature Coefficient (PTC) device comprising the steps of:

providing two nickel-plated copper foils according to claim 1, with the matte sides of the nickel plated copper foils facing, but spaced apart from, each other;

introducing a non-electrically conducting polymer having a plurality of electrically conductive filler contained in the polymer between the two nickel-plated copper foils;

passing the two nickel-plated copper foils and the non-electrically conductive polymer having the electrically conductive filler therein through a hot press; and

,

consolidating the two nickel-plated copper foils and the polymer containing the electrically conductive filler into a unitary product.

14. The method of claim 13, wherein the consolidating comprises applying both heat and pressure.

15. The method of claim 13, further comprising simultaneously passing a stack of a plurality of two nickel-plated copper foils and the non-electrically conductive polymer having electrically conductive filler through the hot press.

16. The method of claim 13, further comprising punching shapes from said unitary product.

17. The method of claim 16, wherein the punched shape is positioned between a positive terminal of a secondary battery and a negative terminal of the secondary battery.

18. Resettable fuses comprising the Positive Temperature Coefficient (PTC) device of claim 10.

19. The resettable fuse of claim 18, in combination with at least one device selected from the group consisting of a computer, a mobile telephone, a battery, an AC power supply, an AC/DC power adapter, an automobile, a portable digital assistant (PDA), a portable multi-media player, an MP3 player, a game console, an USB, a HUB, an industrial control and medical equipment.