METHOD OF PREVENTING OVER-DISCHARGE OF BATTERY

• US 20100076523A1
• Filed: 09/22/2009
• Published: 03/25/2010
• Est. Priority Date: 10/29/2004
• Status: Active Grant

• Current Assignee: Medtronic Incorporated (Medtronic Plc)
• Original Assignee: Medtronic Incorporated (Medtronic Plc)
• Inventors: Howard, William G., Scott, Erik R., Schmidt, Craig L.
• Granted Patent: US 7,883,790 B2
• Time in Patent Office: Days
• US Class Current: 607/61
• CPC Class Codes: A61N 1/378 Electrical supply
• CPC Class Codes: H01M 10/052 Li-accumulators
• CPC Class Codes: H01M 10/0525 Rocking-chair batteries, i.e. batteries with lithium insertion or intercalation in both electrodes; Lithium-ion batteries
• CPC Class Codes: H01M 10/42 Methods or arrangements for servicing or maintenance of secondary cells or secondary half-cells H01M10/60 takes precedence
• CPC Class Codes: H01M 10/4235 Safety or regulating additives or arrangements in electrodes, separators or electrolyte H01M10/4242 takes precedence
• CPC Class Codes: H01M 10/425 Structural combination with electronic components, e.g. electronic circuits integrated to the outside of the casing printed circuits H05K1/00
• CPC Class Codes: H01M 2004/029 Bipolar electrodes
• CPC Class Codes: H01M 4/131 Electrodes based on mixed oxides or hydroxides, or on mixtures of oxides or hydroxides, e.g. LiCoOx
• CPC Class Codes: H01M 4/485 of mixed oxides or hydroxides for inserting or intercalating light metals, e.g. LiTi2O4 or LiTi2OxFy H01M4/505, H01M4/525 take precedence
• CPC Class Codes: H01M 4/505 of mixed oxides or hydroxides containing manganese for inserting or intercalating light metals, e.g. LiMn2O4 or LiMn2OxFy
• CPC Class Codes: H01M 4/525 of mixed oxides or hydroxides containing iron, cobalt or nickel for inserting or intercalating light metals, e.g. LiNiO2, LiCoO2 or LiCoOxFy
• CPC Class Codes: H01M 4/5825 Oxygenated metallic salts or polyanionic structures, e.g. borates, phosphates, silicates, olivines
• CPC Class Codes: H01M 4/661 Metal or alloys, e.g. alloy coatings H01M4/669 take precedence
• CPC Class Codes: H01M 50/409 Separators, membranes or diaphragms characterised by the material
• CPC Class Codes: Y02E 60/10 Energy storage using batteries
• CPC Class Codes: Y10T 29/49108 Electric battery cell making

Abstract

A medical device includes a rechargeable lithium-ion battery for providing power to the medical device. The lithium-ion battery includes a positive electrode including a current collector and a first active material, a negative electrode including a current collector and a second active material, and an auxiliary electrode including a current collector and a third active material. The auxiliary electrode is configured for selective electrical connection to one of the positive electrode and the negative electrode. The first active material, second active material, and third active material are configured to allow doping and undoping of lithium ions. The third active material exhibits charging and discharging capacity below a corrosion potential of the current collector of the negative electrode and above a decomposition potential of the first active material.

Claims

1. A method of preventing over-discharge of a lithium-ion battery, comprising:

providing a positive electrode comprising a current collector and a first active material;

providing a negative electrode comprising a current collector and a second active material; and

providing an auxiliary electrode comprising a current collector and a third active material, wherein the auxiliary electrode is configured for repeated selective electrical connection to the negative electrode when a predetermined condition is met;

the first active material, the second active material, and the third active material being configured to allow doping and undoping of lithium ions, and

the third active material exhibiting charging and discharging capacity below a corrosion potential of the current collector of the negative electrode and above a decomposition potential of the first active material.

2. The method of claim 1, wherein the predetermined condition comprises the potential of the negative electrode exceeding the potential of the auxiliary electrode by a predetermined value.

3. The method of claim 1, wherein the predetermined condition comprises a difference between the voltage of the negative electrode and the positive electrode falling below a predetermined value.

4. The method of claim 1, wherein the step of electrically connecting the auxiliary electrode to the negative electrode comprises connecting the auxiliary electrode to the negative electrode using a diode.

5. The method of claim 1, wherein the step of electrically connecting the auxiliary electrode to the negative electrode comprises connecting the auxiliary electrode to the negative electrode using a switch.

6. The method of claim 5, wherein the step of electrically connecting the auxiliary electrode to the negative electrode further comprises using a control circuit to send a signal to the switch.

7. The method of claim 1, further comprising electrically disconnecting the auxiliary electrode from the negative electrode when a second predetermined condition is met.

8. A method of preventing over-discharge of a lithium-ion battery, comprising:

providing a positive electrode comprising a current collector and a first active material;

providing a negative electrode comprising a current collector and a second active material; and

providing an auxiliary electrode comprising a current collector and a third active material, wherein the auxiliary electrode is configured for repeated selective electrical connection to the positive electrode when a predetermined condition is met;

the first active material, the second active material, and the third active material being configured to allow doping and undoping of lithium ions, and

the third active material exhibiting charging and discharging capacity below a corrosion potential of the current collector of the negative electrode and above a decomposition potential of the first active material.

9. The method of claim 8, wherein the predetermined condition comprises a difference between the voltage of the negative electrode and the positive electrode falling below a predetermined value.

10. The method of claim 8, wherein the predetermined condition comprises a difference between the voltage of the negative electrode and the positive electrode exceeding a predetermined value.

11. The method of claim 8, wherein the step of electrically connecting the auxiliary electrode to the positive electrode comprises connecting the auxiliary electrode to the positive electrode using a diode.

12. The method of claim 8, wherein the step of electrically connecting the auxiliary electrode to the positive electrode comprises connecting the auxiliary electrode to the positive electrode using a switch.

13. The method of claim 12, wherein the step of electrically connecting the auxiliary electrode to the positive electrode further comprises using a control circuit to send a signal to the switch.

14. The method of claim 8, further comprising electrically disconnecting the auxiliary electrode from the positive electrode when a second predetermined condition is met.

15. A method of preventing over-discharge of a battery used while treating a medical condition of a patient comprising:

providing a medical device;

providing a battery in electrical contact with the medical device, the battery comprising;

a positive electrode comprising a current collector and a first active material;

a negative electrode comprising a current collector and a second active material; and

an auxiliary electrode comprising a current collector and a third active material, the auxiliary electrode configured for repeated, selective electrical connection to at least one of the positive electrode and the negative electrode; and

electrically connecting the auxiliary electrode to at least one of the negative electrode or the positive electrode when a predetermined condition is met;

the first active material, the second active material, and the third active material being configured to allow doping and undoping of lithium ions; and

the third active material exhibiting charging and discharging capacity below a corrosion potential of the current collector of the negative electrode and above a decomposition potential of the first active material.

16. The method of claim 15, wherein the predetermined condition comprises the potential of the negative electrode exceeding the potential of the auxiliary electrode by a predetermined value.

17. The method of claim 15, wherein the predetermined condition comprises a difference between the voltage of the negative electrode and the positive electrode falling below a predetermined value.

18. The method of claim 15, wherein the step of electrically connecting the auxiliary electrode to at least one of the negative electrode or the positive electrode further comprises connecting the auxiliary electrode to at least one of the negative electrode or the positive electrode using at least one of a diode or a switch.

19. The method of claim 15, further comprising electrically disconnecting the auxiliary electrode from the negative electrode or the positive electrode when a second predetermined condition is met.

20. The method of claim 15, further comprising the step of implanting at least a portion of the medical device in the patient, and further comprising a step of charging the battery without removing the implanted portion of the medical device from the patient.