Non-aqueous electrochemical cells

• US 7,479,348 B2
• Filed: 04/08/2005
• Issued: 01/20/2009
• Est. Priority Date: 04/08/2005
• Status: Active Grant

• Current Assignee: Duracell U.S. Operations, Inc. (Berkshire Hathaway Incorporated)
• Original Assignee: Gillette Company (The Procter & Gamble Company)
• Inventors: Issaev, Nikolai N., Pozin, Michael
• Primary Examiner(s): Ryan; Patrick
• Assistant Examiner(s): Parsons; Thomas H.
• Application Number:
  US11/101,890
• Publication Number:
  US 20060228624A1
• Time in Patent Office: 1,383 Days
• Field of Search: 429/188, 429/224, 429/231.95, 429/331, 429/207, 429/221, 429/338
• US Class Current: 429/188
• CPC Class Codes: H01M 10/052 Li-accumulators
• CPC Class Codes: H01M 10/0568 characterised by the solutes
• CPC Class Codes: H01M 10/0569 characterised by the solvents
• CPC Class Codes: H01M 2300/0025 Organic electrolyte
• CPC Class Codes: H01M 2300/004 Three solvents
• CPC Class Codes: H01M 4/38 of elements or alloys
• CPC Class Codes: H01M 4/382 Lithium H01M4/405 takes precedence
• CPC Class Codes: H01M 4/387 Tin or alloys based on tin
• 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 4/661 Metal or alloys, e.g. alloy coatings H01M4/669 take precedence
• CPC Class Codes: H01M 4/665 Composites
• CPC Class Codes: H01M 6/164 by the solvent
• CPC Class Codes: H01M 6/166 by the solute
• 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

Abstract

Electrochemical cells are disclosed. In some embodiments, an electrochemical cell includes a cathode, an anode, and an electrolyte having a first lithium salt and LiBF₄.

Claims

1. A primary electrochemical cell, comprising (1) a cathode including an active cathode material selected from the group consisting of manganese dioxide and iron disulfide, the active cathode material including water, (2) an anode comprising lithium (3)an aluminum couple, and (4) an electrolyte, in contact with a surface of the aluminum couple, and comprising (a) from about 300 ppm to about 10,000 ppm of LiBF₄ to reduce corrosion of the aluminum couple, (b) LiPF₆, and (c) a third lithium salt selected from the group consisting of lithium trifluoromethanesulfonate and lithium trifluoromethanesulphonylimide.

2. The cell of claim 1, wherein the third lithium salt comprises lithium trifluoromethanesulfonate.

3. The cell of claim 1, wherein the electrolyte includes both lithium trifluoromethanesulfonate and lithium trifluoromethanesulphonylimide.

4. The cell of claim 1, wherein the active cathode material is manganese dioxide.

5. The cell of claim 1, wherein the aluminum couple includes two aluminum surfaces in electrical contact with each other.

6. The cell of claim 5, wherein the aluminum couple comprises a cathode current collector comprising aluminum and a positive lead comprising aluminum.

7. The cell of claim 1, wherein the electrolyte further comprises a material selected from the group consisting of ethylene carbonate, propylene carbonate, dimethoxyethane, and butylene carbonate.

8. The cell of claim 1, wherein the electrolyte further comprises dimethoxyethane.

9. The cell of claim 1, wherein the electrolyte further comprises ethylene carbonate.

10. The cell of claim 1, wherein the electrolyte further comprises butylene carbonate.

11. The cell of claim 1, wherein the electrolyte comprises dioxolane.

12. The cell of claim 1, wherein the aluminum couple comprises a cathode current collector comprising aluminum in electrical contact with a positive lead comprising a metal other than aluminum.

13. The cell of claim 1, wherein the active cathode material is iron disulfide.

14. The cell of claim 1, wherein the electrolyte comprises lithium salts consisting of (a), (b), and (c).

15. The cell of claim 14, wherein the lithium salts consist of LiBF₄, LiPF₆, and lithium trifluoromethanesulfonate.

16. The cell of claim 1, wherein the electrolyte does not include a perchlorate salt.

17. The cell of claim 1, wherein the electrolyte comprises from about 300 ppm to about 5,000 ppm of LiBF₄.

18. The cell of claim 1, wherein the electrolyte further comprises propylene carbonate.

19. The cell of claim 1, wherein the electrolyte includes at least 0.1 M of LiPF₆ by weight.

20. A method, comprising:

discharging an electrochemical cell only once, the cell comprising

a cathode comprising manganese oxide and/or iron disulfide,

an anode comprising lithium,

an aluminum couple; and

an electrolyte, in contact with a surface of the aluminum couple, and comprising (a)from about 300 ppm to about 10,000 ppm LiBF₄ to reduce corrosion of the aluminum couple, (b) LiPF₆, and (c) a third lithium salt selected from the group consisting of lithium trifluoromethanesulfonate and lithium trifluoromethanesulphonvlimide; and

disposing the cell without recharging the cell.

21. The method of claim 20, wherein the aluminum couple comprises a cathode current collector comprising aluminum in electrical contact with a positive lead comprising a metal other than aluminum.

22. The method of claim 20, wherein the aluminum couple comprises a cathode current collector comprising aluminum in electrical contact with a positive lead comprising aluminum.

23. The method of claim 20, wherein the electrolyte comprises lithium salts consisting of (a), (b), and (c).

24. The method of claim 20, wherein the electrolyte does not include a perchlorate salt.

25. The method of claim 20, wherein the electrolyte comprises a material selected from the group consisting of ethylene carbonate, propylene carbonate, dimethoxyethane, dioxolane,and butylene carbonate.

26. The method of claim 20, wherein the active cathode material is iron disulfide.

27. The cell of claim 20, wherein the electrolyte includes at least 0.1 M of LiPF₆ by weight.

28. A method of making a primary electrochemical cell in which the corrosion of an aluminum couple is suppressed, the method including

adding a sufficient quantity of LiBF₄ to an electrolyte including LiPF₆ and a third lithium salt selected from the group consisting of lithium trifluoromethanesulfonate and lithium trifluoromethanesulphonylimide to shift corrosion potential of an aluminum electrode by at least 127 mV when tested by continuous cyclic voltammetry in an electrochemical glass cell having an aluminum working electrode, a lithium reference electrode, and two lithium auxiliary electrodes, the continuous cyclic voltammetry including cycles in which the potential initially is set to an open circuit potential, then anodically scanned to +4.5 V, and then reversed to an open circuit potential, the scan rate being 50 mV/sec, the corrosion potential being the potential at which anodic current density reached 10⁻

4A/cm² at a first cycle; and

incorporating the electrolyte into an electrochemical cell comprising a cathode including an active cathode material selected from the group consisting of manganese dioxide and iron disulfide, the active cathode material including water, an anode comprising lithium, and an aluminum couple in contact with the electrolyte.

29. The method of claim 28, wherein the method also includes discharging the cell only once and disposing the cell without recharging the cell.

30. The method of claim 28, wherein the aluminum couple includes cathode current collector comprising aluminum is in electrical contact with a positive lead comprising a metal other than aluminum.

31. The method of claim 30, wherein the metal is stainless steel.

32. The method of claim 28, wherein the aluminum couple comprising a cathode current collector comprising aluminum in electrical contact with a positive lead comprising aluminum.

33. The method of claim 28, wherein the active cathode material is iron disulfide.

34. The method of claim 28, wherein the active cathode material is manganese dioxide.

35. The method of claim 28, wherein the electrolyte comprises lithium salts consisting of LiBF₄, LiPF₆, and lithium trifluoromethanesulphonylimide and/or lithium trifluoromethanesulfonate.

36. The method of claim 35, wherein the lithium salts consist of LiBF₄, LiPF₆,and lithium trifluoromethanesulphonylimide.

37. The method of claim 35, wherein the lithium salts consist of LiBF₄, LiPF₆, and lithium trifluoromethanesulfonate.

38. The method of claim 28, wherein the electrolyte does not include a perchlorate salt.

39. The method of claim 28, wherein the electrolyte comprises from about 300 ppm to about 5,000 ppm of the LiBF₄.

40. The method of claim 28, wherein the electrolyte comprises a material selected from the group consisting of ethylene carbonate, propylene carbonate, dimethoxyethane, and butylene carbonate.

41. The method of claim 28, wherein the electrolyte comprises dioxolane.

42. The cell of claim 28, wherein the electrolyte includes at least 0.1 M of LiPF₆ by weight.