Metallic surface with karstified relief, forming same, and high surface area metallic electrochemical interface

Patent metadata

Field	Value
Publication number	US-10522300-B2
Application number	US-201615165584-A
Country	US
Kind code	B2
Filing date	May 26, 2016
Priority date	May 26, 2015
Publication date	Dec 31, 2019
Grant date	Dec 31, 2019

Abstract

A metal foil with a karstified topography having a surface morphology in which a maximum peak height minus a maximum profile depth is greater than 0.5 μm and extends into the surface at least 5% of the foil thickness, a root mean square roughness is at least about 0.2 μm measured in a direction of greatest roughness, and an oxygen abundance is less than 5 atomic %. The foil may be composed of aluminum, titanium, nickel, copper, or stainless steel, or an alloy of any thereof, and may have a coating composed of nickel, nickel alloy, titanium, titanium alloy, nickel oxide, titanium dioxide, zinc oxide, indium tin oxide, or carbon, or a mixture or composite of any thereof. The foil may form part of a metal electrode, current collector, or electrochemical interface. Further described is a method for producing the foil by laser ablation in a vacuum.

First claim

The invention claimed is:

1. A method for producing a metal foil less than 0.5 mm thick, the metal foil having a karstified topography having a surface morphology in which a maximum peak height minus a maximum profile depth is greater than 0.5 μm and extends into the surface at least 5% of the foil thickness, a root mean square roughness is at least about 0.2 μm measured in a direction of greatest roughness, and an oxygen abundance is less than 5 atomic %, the method comprising:
providing a metal foil with a thickness less than 0.5 mm, retained in place within a vacuum chamber;
evacuating the chamber to a pressure less than 7×10 −3 Pa; and
applying a high power laser radiation to the surface of the metal foil, the radiation having an irradiance sufficient to ablate the metal, leaving the karstified topography on the surface of the metal foil.

2. The method of claim 1 wherein:
the surface morphology has a height distribution that is at least approximately Gaussian, a skewness less than +/−1.5, and a kurtosis in a range of 2-11;
profiles of the surface morphology, defined as a height of the surface along a line segment in a plane of the surface, establish that a mean separation of peaks and valleys is less than 50 microns; or
profiles of the surface morphology, defined as a height of the surface along a line segment in a plane of the surface, establish that at least 5% of the slope of the profiles are greater than 5 or less than −5.

3. The method of claim 2 wherein the maximum profile depth is at least 2% of the foil thickness.

4. The method of claim 3 wherein the foil is composed of a metal that naturally forms an oxide that has a higher electrical resistance than the metal, and the method further comprises applying a passivating layer onto the karstified topography, the passivating layer having a higher electrical conductivity and/or corrosion resistance than that of the oxide.

5. The method of claim 4 wherein applying the passivating layer comprises depositing the passivating layer in the vacuum chamber.

6. The method of claim 4 wherein applying the passivating layer comprises applying a physical vapour deposition (PVD) process.

7. The method of claim 4 wherein applying the passivating layer comprises applying a pulsed laser deposition process that uses a same laser as was used to produce the karstified topography.

8. The method of claim 4 wherein the foil is composed of Al, Ni, Ti, Cu, or stainless steel or an alloy or mixture of any two or more thereof, and the passivating layer is composed of one or more metals, one or more alloys, carbon, a carbon metal composite, or one or more metal oxides, or any combination of two or more thereof.

9. The method of claim 3 wherein providing the foil comprises mounting a foil to a reel-to-reel system within the vacuum chamber.

10. The method of claim 3 wherein the foil is 0.01-0.2 mm thick or 0.020-0.050 mm thick.

11. The method of claim 1 wherein applying a high power laser radiation pattern to the surface comprises:
moving one or more lasers, or optical components for redirecting a beam from the one or more lasers, with respect to the surface to produce a time-varying high power electromagnetic radiation pattern;
moving one or more lasers that are located outside of the vacuum chamber with respect to a window of the vacuum chamber;
operating a short pulse, high energy laser with focusing optics to focus the energy to achieve high spatio-temporal focusing of the electromagnetic radiation;
operating a femtosecond laser;
operating a picosecond laser;
operating a nanosecond laser;
operating an eximer laser; or
operating a Q-switched Nd-YAG solid state laser.

12. A metal foil less than 0.5 mm thick, the metal foil having a karstified topography having a surface morphology in which:
a maximum peak height minus a maximum profile depth is greater than 0.5 μm and extends into the surface at least 5% of the foil thickness;
a root mean square roughness is at least about 0.2 μm measured in a direction of greatest roughness; and
an oxygen abundance is less than 5 atomic %.

13. The foil of claim 12 wherein profiles of the surface morphology, defined as a height of the surface along a line segment in a plane of the surface, establish that a mean separation of peaks and valleys is less than 50 microns.

14. The foil of claim 13 wherein the profiles establish that at least 5% of the slope of the profiles are greater than 5 or less than −5.

15. The foil of claim 12 wherein the surface morphology has a height distribution that is at least approximately Gaussian, has a skewness less than +/−1.5, and a kurtosis in a range of 2-11.

16. The foil of claim 12 wherein the foil is composed of a metal or alloy that resists corrosion and is electrically conductive.

17. The foil of claim 12 wherein the foil is composed of Al, an Al alloy, stainless steel, Cu, Ag, Ni, Ti, or a mixture or alloy of any two or more thereof.

18. The foil of claim 12 wherein the foil is coated with a metal, alloy, carbon, carbon metal composite or metal oxide that resists oxidation/corrosion and/or is electrically conductive.

19. The foil of claim 12 wherein the foil is composed of Al, an Al alloy, Cu, or a Cu alloy, and has a coating of a metal, alloy, carbon, carbon metal composite, metal oxide, or a combination of any two or more thereof.

20. The foil of claim 12 wherein the foil is composed of Al, an Al alloy, Cu, or a Cu alloy, and has a coating of nickel, a nickel alloy, titanium, a titanium alloy, carbon, a carbon metal composite, nickel oxide, titanium dioxide, zinc oxide, or indium tin oxide, or a mixture of any two or more thereof.

21. The foil of claim 12 wherein the foil thickness is less than 0.5 mm and the maximum peak height minus maximum profile depth is more than 5% of the foil thickness.

22. The foil of claim 12 , the foil being comprised within an electrochemical interface and having a first face facing an active material, the first face bearing the karstified topography.

23. The foil of claim 22 wherein profiles of the surface morphology, defined as a height of the surface along a line segment in a plane of the surface, establish that a mean separation of peaks and valleys is less than 50 microns.

24. The foil of claim 23 wherein the profiles establish that at least 5% of the slope of the profiles are greater than 5 or less than −5.

25. The foil of claim 22 wherein the surface morphology has a height distribution that is at least approximately Gaussian, has a skewness less than +/−1.5, and a kurtosis in a range of 2-11.

26. The foil of claim 22 wherein the foil is composed of a metal or alloy that resists corrosion and is electrically conductive.

27. The foil of claim 22 wherein the foil is coated with a metal, alloy, carbon, carbon metal composite, or metal oxide that resists corrosion and is electrically conductive.

28. The foil of claim 22 wherein the foil is less than 0.5 mm thick, 0.01-0.2 mm thick, or 0.020-0.050 mm thick, and the maximum peak height minus maximum profile depth is 5-50% of the foil thickness.

29. The foil of claim 12 wherein the foil thickness is 0.01-0.2 mm and the maximum peak height minus maximum profile depth is more than 5% of the foil thickness.

30. The foil of claim 12 wherein the foil thickness is 0.020-0.050 mm and the maximum peak h

Assignees

• Nat Res Council Canada

Inventors

• Yang Dongfang

Classifications

• B23K26/3568

  Modifying rugosity · CPC title

• H01M4/0426

  Sputtering · CPC title

• B23K26/0823

  Devices involving rotation of the workpiece · CPC title

• H01G11/70

  characterised by their structure · CPC title

• B23K26/127

  in an enclosure · CPC title