Capacitor and method for producing a capacitor

• US 7,499,260 B2
• Filed: 05/25/2006
• Issued: 03/03/2009
• Est. Priority Date: 09/30/2002
• Status: Expired due to Term

• Current Assignee: Medtronic Incorporated (Medtronic Plc), Kemet Electronics Corporation (Yageo Corporation)
• Original Assignee: Medtronic Incorporated (Medtronic Plc), Kemet Electronics Corporation (Yageo Corporation)
• Inventors: Kinard, John Tony, Schott, Joachim Hossick, Melody, Brian
• Primary Examiner(s): THOMAS, ERIC W
• Application Number:
  US11/440,922
• Publication Number:
  US 20060227496A1
• Time in Patent Office: 1,013 Days
• Field of Search: 361502-503, 361508-511, 361/516, 361523-526, 361528-532, 607/5
• US Class Current: 361/503
• CPC Class Codes: A61N 1/3975 Power supply A61N1/378 takes precedence
• CPC Class Codes: H01G 11/30 characterised by their material
• CPC Class Codes: H01G 11/32 Carbon-based
• CPC Class Codes: H01G 9/008 Terminals
• CPC Class Codes: H01G 9/042 characterised by the material H01G11/22 takes precedence
• CPC Class Codes: H01G 9/0425 specially adapted for cathode
• CPC Class Codes: H01G 9/06 Mounting in containers
• CPC Class Codes: Y02E 60/13 Energy storage using capacitors

Abstract

An electrode for an electrolytic capacitor includes a substrate comprising titanium; a carbide layer adjacent the substrate; and a carbonaceous layer adjacent the carbide layer and including means for enhancing the capacitance of the electrode.

Claims

1. An electrode for an electrolytic capacitor comprising:

a substrate comprising titanium;

a carbide layer adjacent the substrate; and

a carbonaceous layer adjacent the carbide layer and including means for enhancing the capacitance of the electrode.

2. The electrode of claim 1, wherein the means for enhancing the capacitance of the electrode comprises activated carbon.

3. The electrode of claim 2, wherein the activated carbon includes functional groups that include oxygen, the functional groups being selected from CO, COOH, and C═

O.

4. The electrode of claim 2, wherein the means for enhancing the capacitance of the electrode further comprises an oxide of manganese.

5. The electrode of claim 1, wherein the carbide layer comprises titanium.

6. The electrode of claim 1, wherein the electrode is a cathode for an electrolytic capacitor.

7. The electrode of claim 1, wherein the electrode has a capacitance of greater than approximately 10 milliFarads per square centimeter.

8. The electrode of claim 1, wherein the substrate has a roughness of between approximately 2 and 5 micrometers.

9. The electrode of claim 1, wherein the thickness of the carbide layer is less than approximately 10 nanometers.

10. A capacitor comprising:

a cathode;

an anode; and

an electrolyte provided intermediate the cathode and the anode;

wherein the cathode comprises;

a substrate comprising titanium;

a carbide layer adjacent the substrate; and

a carbonaceous layer adjacent the carbide layer comprising a material for enhancing the capacitance of the cathode.

11. The capacitor of claim 10, wherein the material for enhancing the capacitance of the cathode comprises activated carbon and an oxide of manganese.

12. The capacitor of claim 10, wherein the carbide layer comprises titanium.

13. The capacitor of claim 10, wherein the cathode has a capacitance of greater than approximately 10 milliFarads per square centimeter.

14. The capacitor of claim 10, wherein the substrate has a roughness of between approximately 2 and 5 micrometers.

15. The capacitor of claim 10, wherein the thickness of the carbide layer is less than approximately 10 nanometers.

16. An implantable medical device comprising:

an electrolytic capacitor having a cathode, an anode, and an electrolyte intermediate the cathode and the anode;

wherein the cathode comprises;

a substrate comprising titanium;

a carbide layer adjacent the substrate; and

a carbonaceous layer adjacent the carbide layer comprising a material for enhancing the capacitance of the cathode;

wherein the implantable medical device is configured to provide a therapeutic high voltage treatment.

17. The implantable medical device of claim 16, wherein the material for enhancing the capacitance of the cathode comprises activated carbon and an oxide of manganese.

18. The implantable medical device of claim 16, wherein the carbide layer comprises titanium.

19. The implantable medical device of claim 16, wherein the cathode has a capacitance of greater than approximately 10 milliFarads per square centimeter.

20. The implantable medical device of claim 16, wherein the thickness of the carbide layer is less than approximately 10 nanometers.

21. An electrolytic capacitor comprising:

a first electrode;

an electrolyte; and

a second electrode comprising;

a substrate comprising a metal;

a carbide layer provided proximate the substrate, and

a layer of material configured to enhance the capacitance of the second electrode;

wherein the second electrode is an anode and the metal comprises aluminum.

22. The electrolytic capacitor of claim 21, wherein the substrate comprises a surface, the surface having a roughness of between approximately 2 and 5 micrometers.

23. An electrolytic capacitor comprising:

a first electrode;

an electrolyte; and

a second electrode comprising;

a substrate comprising a metal selected from the group consisting of titanium, aluminum, tantalum, niobium, zirconium, silver, and steel, and alloys and combinations thereof;

a carbide layer provided proximate the substrate, and

a layer of material configured to enhance the capacitance of the second electrode;

wherein the second electrode further comprises at least one material selected from the group consisting of aluminum, titanium, niobium, zirconium, and combinations thereof.

24. An electrolytic capacitor comprising:

a first electrode;

an electrolyte; and

a second electrode comprising;

a substrate comprising a metal;

a carbide layer provided proximate the substrate, the carbide layer comprising titanium carbide; and

a layer of material configured to enhance the capacitance of the second electrode.

25. An electrolytic capacitor comprising:

a first electrode;

an electrolyte; and

a second electrode comprising;

a substrate comprising a metal selected from the group consisting of titanium, aluminum, tantalum, niobium, zirconium, silver, and steel, and alloys and combinations thereof;

a carbide layer provided proximate the substrate, and

a layer of material configured to enhance the capacitance of the second electrode;

wherein the layer of material comprises a carbonaceous material that comprises activated carbon and an oxide of manganese.