Flat capacitor having staked foils and edge-connected connection members

• US 20080154319A1
• Filed: 02/28/2008
• Published: 06/26/2008
• Est. Priority Date: 11/03/2000
• Status: Active Grant

• Current Assignee: Cardiac Pacemakers Incorporated (Boston Scientific Corporation)
• Original Assignee: Cardiac Pacemakers Incorporated (Boston Scientific Corporation)
• Inventors: Iyer, Rajesh, Poplett, James M., O'Phelan, Michael J., Tong, Robert R., Barr, Alexander Gordon
• Granted Patent: US 8,543,201 B2
• Time in Patent Office: Days
• US Class Current: 607/5
• CPC Class Codes: A61N 1/378 Electrical supply
• CPC Class Codes: A61N 1/3956 Implantable devices for applying electric shocks to the heart, e.g. for cardioversion
• CPC Class Codes: A61N 1/3968 Constructional arrangements, e.g. casings A61N1/375 takes precedence
• CPC Class Codes: A61N 1/3975 Power supply A61N1/378 takes precedence
• CPC Class Codes: H01G 2/106 Fixing the capacitor in a housing
• CPC Class Codes: H01G 9/008 Terminals
• CPC Class Codes: H01G 9/06 Mounting in containers
• CPC Class Codes: H01G 9/08 Housing; Encapsulation

Abstract

A method of joining a connection member to a capacitor foil using a staking tool having a tip of less than 0.030″ (0.762 mm) in diameter. Another embodiment couples multiple connection members of a capacitor together by edge-connecting each connection member to its substantially flush neighboring connection members. In one aspect, a capacitor includes a multi-anode stack connected at a first weld by a weld joint less than 0.060″ (1.524 mm) in diameter and a tab attached to one of the anodes of the multi-anode stack at a second weld. In one aspect, an exemplary method joining one or more foils using a staking tool having a tip of less than approximately 0.060″ (1.524 mm) in diameter. In another aspect, a capacitor including a capacitor case having an electrolyte therein and a high formation voltage anode foil having a porous structure and located within the capacitor case.

Claims

1. An implantable medical device comprising:

one or more leads for sensing electrical signals of a patient or for applying electrical energy to the patient;

a monitoring circuit for monitoring heart activity of the patient through one or more of the leads; and

a therapy circuit for delivering electrical energy through one or more of the leads to a heart of the patient, wherein the therapy circuit includes a capacitor, the capacitor comprising;

a plurality of anodes, each anode comprising an anode foil having a formation voltage of approximately 441 volts or greater and having a porous structure;

a plurality of cathodes; and

a plurality of electrolyte impregnated separators, at least one of the plurality of electrolyte impregnated separators located between each anode and each cathode.

2. The implantable medical device of claim 1, wherein the anode foil has a formation voltage of approximately 600 volts or higher.

3. The implantable medical device of claim 1, wherein the therapy circuit includes a single capacitor.

4. The implantable medical device of claim 1, wherein each anode foil has a formation voltage of between approximately 441 volts and approximately 600 volts.

5. The implantable medical device of claim 1, wherein each anode foil has a formation voltage of between approximately 600 volts and approximately 800 volts.

6. The implantable medical device of claim 1, further comprising a connection member attached to at least one anode foil, the connection member having a first section extending over and confronting the edge face of the anode foil, wherein the connection member comprises a main member having a generally L-shaped cross-section.

7. An implantable medical device comprising:

one or more leads for sensing electrical signals of a patient or for applying electrical energy to the patient;

a monitoring circuit for monitoring heart activity of the patient through one or more of the leads; and

a therapy circuit for delivering electrical energy through one or more of the leads to a heart of the patient, wherein the therapy circuit includes one or more capacitors, each capacitor comprising;

a multi-anode stack comprising two or more anode foils;

a cathode; and

a separator located between the anode stack and the cathode;

wherein, each anode foil of the multi-anode stack is interconnected to the other foils of the multi-anode stack at a stake weld joint having a diameter of less than approximately 0.060″

(1.524 mm).

8. The implantable medical device of claim 7, wherein the stake weld has a diameter of approximately 0.025″

(0.635 mm).

9. The implantable medical device of claim 7, wherein each of the two or more anode foils comprises a tunnel-etched foil.

10. The implantable medical device of claim 7, wherein each of the anode foils comprises an anode foil having a porous structure and a formation voltage of greater than approximately 441 volts.

11. The implantable medical device of claim 7, wherein each of the anode foils has a formation voltage of approximately 600 volts or higher.

12. The implantable medical device of claim 11, wherein each of the anode foils has a formation voltage between approximately 600 volts and approximately 800 volts.

13. The implantable medical device of claim 7, further comprising a second multi-anode stack including two or more anode foils, wherein each anode foil of the second multi-anode stack is connected to the other foils of the second multi-anode stack by a stake weld joint having a diameter less than approximately 0.060″

(1.524 mm), and wherein the stake weld joint of the first anode stack is in a different location relative to a major surface of the first multi-anode stack than the stake weld joint of the second multi-anode stack.

14. The implantable medical device of claim 7, wherein the capacitor comprises a flat capacitor.

15. An implantable medical device comprising:

one or more leads for sensing electrical signals of a patient or for applying electrical energy to the patient;

a monitoring circuit for monitoring heart activity of the patient through one or more of the leads; and

a therapy circuit for delivering electrical energy through one or more of the leads to a heart of the patient, wherein the therapy circuit includes one or more capacitors, each capacitor comprising;

a plurality of anodes, each anode having an edge surface;

a plurality of connection members, each of the plurality of connection members attached to one of the plurality of anodes, each connection member comprising a member having a surface confronting the edge surface of at least one anode;

a plurality of cathodes; and

a plurality of electrolyte impregnated separators, at least one of the plurality of electrolyte impregnated separators located between each anode and each cathode.

16. The implantable medical device of claim 15, wherein each anode connection member is connected to each other anode connection member adjacent to each anode connection member by an edge-connection.

17. The implantable medical device of claim 15, wherein each anode connection member is connected to each anode by a stake weld having a diameter of approximately 0.030″

(0.762 mm) or less.

18. The implantable medical device of claim 15, wherein at least one of the anodes includes a notch, the connection member having a section fitting within the notch.

19. The implantable medical device of claim 18, wherein the connection member includes a generally L-shaped cross-section.

20. The implantable medical device of claim 19, wherein the L-shaped connection member includes a first section connected to a top surface of the anode and a second section extending over the edge of the anode.