Claims
- 1. An electrochemical cell, which comprises:
a) a negative electrode comprising an anode material capable of intercalating and de-intercalating an alkali metal; b) a positive electrode comprising a cathode active material capable of intercalating and de-intercalating the alkali metal; and c) an electrolyte activating the negative electrode and the positive electrode, wherein a ratio of the cathode active material to the anode material is from about 1.35 to about 2.25.
- 2. The electrochemical cell of claim 1 wherein the anode material is selected from the group consisting of coke, graphite, acetylene black, carbon black, glassy carbon, hairy carbon, and mixtures thereof.
- 3. The electrochemical cell of claim 1 wherein the cathode active material is selected from the group consisting of oxides, sulfides, selenides and tellurides of vanadium, titanium, chromium, copper, molybdenum, niobium, iron, nickel, cobalt, manganese, and mixtures thereof.
- 4. The electrochemical cell of claim 1 wherein the cathode active material is selected from the group consisting of LiNiO2, LiMn2O4, LiCoO2, LiCo0.92Sn0.08O2, LiCo1−xNixO2, and mixtures thereof.
- 5. An electrochemical cell, which comprises:
a) a negative electrode comprising a carbonaceous material capable of intercalating and de-intercalating lithium; b) a positive electrode comprising a lithiated cathode active material capable of intercalating and de-intercalating lithium; and c) an electrolyte activating the negative electrode and the positive electrode, wherein a ratio of the cathode active material to the anode material is from about 1.35 to about 2.25.
- 6. The electrochemical cell of claim 5 wherein the cathode active material is lithium cobalt oxide.
- 7. The electrochemical cell of claim 5 wherein the cell is capable of being changed to at least about 4.4 volts.
- 8. The electrochemical cell of claim 5 wherein the electrolyte comprises at least one first solvent selected from an ester, a linear ether and a cyclic ether, and at least one second solvent selected from a cyclic carbonate, a cyclic ester and a cyclic amide.
- 9. The electrochemical cell of claim 5 wherein the electrolyte includes a lithium salt.
- 10. The electrochemical cell of claim 5 contained within an implantable medical device.
- 11. An electrochemical cell, which comprises:
a) a negative electrode comprising a carbonaceous material capable of intercalating and de-intercalating lithium; b) a positive electrode comprising lithium cobalt oxide; and c) an electrolyte activating the negative electrode and the positive electrode, wherein a ratio of the cathode active material to the anode material provided a cathode capacity of from about 165 mAh/gram to about 225 mAh/gram at a rate of about C/5.
- 12. An electrochemical cell, which comprises:
a) a negative electrode comprising a carbonaceous material capable of intercalating and de-intercalating lithium; b) a positive electrode comprising lithium cobalt oxide; and c) an electrolyte activating the negative electrode and the positive electrode, wherein a ratio of the cathode active material to the anode material provided a cathode capacity of from about 165 mAh/gram to about 245 mAh/gram at a rate of about C/50.
- 13. In an implantable medical device comprising an electrochemical cell which is capable of powering the device, the improvement in the cell which comprises:
a) a negative electrode comprising a carbonaceous material capable of intercalating and de-intercalating lithium; b) a positive electrode comprising a lithiated cathode active material capable of intercalating and de-intercalating lithium; and c) an electrolyte activating the negative electrode and the positive electrode, wherein a ratio of the cathode active material to the anode material is from about 1.35 to about 2.25.
- 14. The implantable medical device of claim 13 wherein the lithiated cathode active material is selected from the group consisting of LiNiO2, LiMn2O4, LiCoO2, LiCo0.92Sn0.08O2, LiCo1−xNixO2, and mixtures thereof.
- 15. The implantable medical device of claim 13 wherein the cell is capable of being charged to at least about 4.4 volts.
- 16. The implantable medical device of claim 13 wherein the cell is dischargeable to deliver a current of from about 100 milliamperes to about 4 amps.
- 17. A method for providing electrical energy, comprising the steps of:
a) providing an electrochemical cell comprising the steps of:
i) providing a negative electrode comprising a carbonaceous material capable of intercalating and de-intercalating lithium; ii) providing a positive electrode comprising a lithiated cathode active material capable of intercalating and de-intercalating lithium; iii) housing the negative electrode and the positive electrode in a casing; and iv) activating the negative electrode and the positive electrode with an electrolyte; b) connecting the cell to an external load; and c) powering the load with the cell.
- 18. The method of claim 17 including selecting the lithiated cathode active material from the group consisting of LiNiO2, LiMn2O4, LiCoO2, LiCo0.92Sn0.08O2, LiCo1−xNixO2, and mixtures thereof.
- 18. The method of claim 17 including powering an implantable medical device as the external load.
- 19. The method of claim 17 including powering the external load with a current of from about 100 milliamperes to about 4 amps delivered from the cell.
- 20. The method of claim 17 including provided lithium cobalt oxide as the cathode active material and the cell having a cathode capacity of from about 165 mAh/gram to about 245 mAh/gram at a rate of about C/50.
- 21. The method of claim 17 including provided lithium cobalt oxide as the cathode active material and the cell having a cathode capacity of from about 165 mAh/gram to about 225 mAh/gram at a rate of about C/5.
CROSS REFERENCE TO RELATED APPLICATION
[0001] This application claims priority based on provisional application Serial No. 60/341,552, filed Dec. 17, 2001.
Provisional Applications (1)
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Number |
Date |
Country |
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60341552 |
Dec 2001 |
US |