Process for prelithiation of carbon based anodes for lithium batteries

• US 5,595,837 A
• Filed: 04/12/1995
• Issued: 01/21/1997
• Est. Priority Date: 04/12/1995
• Status: Expired due to Fees

• Current Assignee: Valence Technology Incorporated (Lithium Werks B.V.)
• Original Assignee: Valence Technology Incorporated (Lithium Werks B.V.)
• Inventors: Olsen, Ib I., Koksbang, Rene
• Primary Examiner(s): Skapars, Anthony
• Application Number:
  US08/422,185
• Time in Patent Office: 650 Days
• Field of Search: 429/194, 429/218, 429/224, 423/179.5, 423/460, 29/623.1, 29/623.5, 205/59
• US Class Current: 429/224
• CPC Class Codes: H01M 10/049 Processes for forming or storing electrodes in the battery container
• CPC Class Codes: H01M 10/05 Accumulators with non-aqueous electrolyte H01M10/39 takes precedence
• 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 10/446 Initial charging measures
• CPC Class Codes: H01M 4/13 Electrodes for accumulators with non-aqueous electrolyte, e.g. for lithium-accumulators; Processes of manufacture thereof
• CPC Class Codes: H01M 4/587 for inserting or intercalating light metals
• CPC Class Codes: H01M 6/181 with polymeric electrolytes
• CPC Class Codes: Y02E 60/10 Energy storage using batteries
• CPC Class Codes: Y02P 70/50 Manufacturing or production processes characterised by the final manufactured product
• CPC Class Codes: Y10T 29/49108 Electric battery cell making

Abstract

A method of increasing the amount of alkali metal that is available during charge/discharge of an electrochemical cell that employs carbon based intercalation anodes is provided. The method comprises of prealkaliation of the carbon anode. By subjecting the anode carbon to the prealkaliation process prior to packaging the electrochemical cell, substantially all the alkali metal (e.g., lithium) which is originally present in the cathode will be available for migration between the anode and cathode during charge/discharge.

Claims

1. A method for fabricating an electrochemical cell which comprises the steps of:

(a) preparing a carbon anode in a process comprising of;

(i) providing a carbon material that is capable of intercalating lithium metal; and

(ii) prelithiating the carbon material with lithium metal;

(b) providing a cathode that comprises a lithiated compound; and

(c) forming a solvent-containing electrolyte that is interposed between said anode and said cathode.

2. The method according to claim 1 wherein after step (a) of preparing the carbon anode the method further comprises the step of removing some or essentially all intercalated lithium metal from the carbon material.

3. The method according to claim 1 wherein the prelithiation step comprises:

positioning a prelithiation electrolyte between the carbon material and the lithium metal; and

electrically connecting the carbon material to the lithium metal.

4. The method according to claim 1 wherein the prelithiation step comprises polarizing the carbon material in a galvanic cell.

5. The method according to claim 1 wherein the cathode includes material selected from the group consisting of LiCoO₂, LiMn₂ O₄, and mixtures thereof.

6. The method according to claim 3 wherein the prelithiation step comprises of polarizing the carbon material in a galvanic cell.

7. The method according to claim 6 wherein the cathode includes material selected from the group consisting of LiCoO₂, LiMn₂ O₄, and mixtures thereof.

8. The method according to claim 3 wherein the prelithiation step comprises of maintaining a constant potential between the carbon material and lithium metal.

9. The method according to claim 8 wherein the cathode includes material selected from the group consisting of LiCoO₂, LiMn₂ O₄, and mixtures thereof.

19. The method according to claim 1, wherein the prelithiation step causes a portion of the carbon material to undergo an irreversible reaction with the lithium metal.

20. The method according to claim 3, wherein the prelithiation step causes a portion of the carbon material to undergo an irreversible reaction with the lithium metal.

21. The method according to claim 4, wherein the prelithiation step causes a portion of the carbon material to undergo an irreversible reaction with the lithium metal.

22. The method according to claim 8, wherein the prelithiation step causes a portion of the carbon material to undergo an irreversible reaction with the lithium metal.

27. The method according to claim 1, wherein the prelithiation occurs at a temperature above 23°

C.

28. The method according to claim 1, wherein the prelithiation occurs at a temperature range of 50°

C. to 100°

C.

29. The method according to claim 3, wherein the prelithiation occurs at a temperature above 23°

C.

30. The method according to claim 3, wherein the prelithiation occurs at a temperature range of 50°

C. to 100°

C.

31. The method according to claim 4, wherein the prelithiation occurs at a temperature above 23°

C.

32. The method according to claim 4, wherein the prelithiation occurs at a temperature range of 50°

C. to 100°

C.

33. The method according to claim 8, wherein the prelithiation occurs at a temperature above 23°

C.

34. The method according to claim 8, wherein the prelithiation occurs at a temperature from 50°

C. to 100°

C.

10. An electrochemical cell fabricated by a process comprising the steps of:

(a) preparing a carbon anode in a process comprising of;

(i) providing a carbon material that is capable of intercalating lithium metal; and

(ii) prelithiating said carbon material with lithium metal;

(b) providing a cathode that comprises a lithiated compound; and

(c) forming a solvent-containing electrolyte that is interposed between said anode and said cathode.

11. The electrochemical cell according to claim 10 wherein the process of fabricating the cell, after step (a) of preparing the carbon anode, further comprises the step of removing some or essentially all intercalated lithium metal from the carbon material.

12. The electrochemical cell according to claim 10 wherein the prelithiation step comprises of polarizing the carbon material in a galvanic cell.

13. The electrochemical cell according to claim 10 wherein the prelithiation step comprises:

positioning a prelithiation electrolyte between the carbon material and the lithium metal; and

electrically connecting the carbon material to the lithium metal.

14. The electrochemical cell according to claim 10 wherein the cathode includes material selected from the group consisting of LiCoO₂, LiMn₂ O₄, and mixtures thereof.

15. The electrochemical cell according to claim 13 wherein the prelithiation step comprises polarizing the carbon material in a galvanic cell.

16. The electrochemical cell according to claim 15 wherein the cathode comprises material selected from the group consisting of LiCoO₂, LiMn₂ O₄, and mixtures thereof.

17. The electrochemical cell according to claim 13 wherein the prelithiation step comprises of maintaining a constant potential between the carbon material and lithium metal.

18. The electrochemical cell according to claim 17 wherein the cathode comprises material selected from the group consisting of LiCoO₂, LiMn₂ O₄, and mixtures thereof.

23. The electrochemical cell according to claim 10, wherein the prelithiation step causes a portion of the carbon material to undergo an irreversible reaction with the lithium metal.

24. The electrochemical cell according to claim 12, wherein the prelithiation step causes a portion of the carbon material to undergo an irreversible reaction with the lithium metal.

25. The electrochemical cell according to claim 13, wherein the prelithiation step causes a portion of the carbon material to undergo an irreversible reaction with the lithium metal.

26. The electrochemical cell according to claim 17, wherein the prelithiation step causes a portion of the carbon material to undergo an irreversible reaction with the lithium metal.

35. The electrochemical cell according to claim 10, wherein the prelithiation occurs at a temperature above 23°

C.

36. The electrochemical cell according to claim 10, wherein the prelithiation occurs at a temperature from 50°

C. to 100°

C.

37. The electrochemical cell according to claim 12, wherein the prelithiation occurs at a temperature above 23°

C.

38. The electrochemical cell according to claim 12, wherein the prelithiation occurs at a temperature from 50°

C. to 100°

C.

39. The electrochemical cell according to claim 13, wherein the prelithiation occurs at a temperature above about 23°

C.

40. The electrochemical cell according to claim 13, wherein the prelithiation occurs at a temperature from 50°

C. to 100°

C.

41. The electrochemical cell according to claim 17, wherein the prelithiation occurs at a temperature above 23°

C.

42. The electrochemical cell according to claim 17, wherein the prelithiation occurs at a temperature from 50°

C. to 100°

C.