Lithium-ion battery

• US 8,105,714 B2
• Filed: 07/13/2007
• Issued: 01/31/2012
• Est. Priority Date: 10/29/2004
• Status: Active Grant

• Current Assignee: Medtronic Incorporated (Medtronic Plc)
• Original Assignee: Medtronic Incorporated (Medtronic Plc)
• Inventors: Schmidt, Craig L., Scott, Erik R., Howard, William G., Jain, Gaurav
• Primary Examiner(s): WEINER, LAURA S
• Application Number:
  US11/777,628
• Publication Number:
  US 20080020279A1
• Time in Patent Office: 1,663 Days
• Field of Search: 429/209, 429/231.5, 429/231.1, 429/221, 429/149, 429/162
• US Class Current: 429/209
• CPC Class Codes: H01M 10/0566 Liquid materials
• CPC Class Codes: H01M 10/0587 of accumulators having only wound construction elements, i.e. wound positive electrodes, wound negative electrodes and wound separators
• 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 4/622 being polymers
• CPC Class Codes: H01M 4/661 Metal or alloys, e.g. alloy coatings H01M4/669 take precedence
• 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

A lithium-ion battery includes a plurality of generally planar positive and negative electrodes arranged in alternating fashion to form an electrode stack. Each of the electrodes includes a current collector having two opposed surfaces and an active material provided on at least one of the two opposed surfaces. The active material of the negative electrodes has a potential that is greater than 0.2 volts versus a reference electrode. The area of the current collectors of the negative electrodes covered by active material is not larger than the area of the current collectors of the positive electrodes covered by active material.

Claims

1. A lithium-ion battery comprising:

a plurality of generally planar positive and negative electrodes arranged in alternating fashion to form an electrode stack, each of the electrodes comprising a current collector having two opposed surfaces and an active material provided on at least one of the two opposed surfaces;

wherein the active material of the negative electrodes has a potential that is greater than 0.2 volts versus a lithium reference electrode;

wherein the area of the current collectors of the negative electrodes covered by active material is not larger than the area of the current collectors of the positive electrodes covered by active material.

2. The lithium-ion battery of claim 1, wherein the area of the current collectors of the positive electrodes covered by active material is greater than the area of the current collectors of the negative electrodes covered by active material.

3. The lithium-ion battery of claim 1, wherein the current collectors comprise at least one edge and the active material of the negative electrodes extends to the at least one edge of the current collectors.

4. The lithium-ion battery of claim 1, wherein negative electrodes do not have a larger surface area than that of the positive electrodes.

5. The lithium-ion battery of claim 1, wherein the electrodes include a plurality of edges and first edges of the positive electrodes are provided adjacent first edges of the negative electrodes, and the active material of the negative electrodes does not extend beyond the first edges of the positive electrodes.

6. The lithium-ion battery of claim 5, wherein the active material of the negative electrodes does not extend beyond the active material of the positive electrodes near the first edges.

7. The lithium-ion battery of claim 1, wherein the active material provided on the negative electrodes has a potential that is greater than 0.3 volts versus a lithium reference electrode.

8. The lithium-ion battery of claim 1, wherein the active material provided on the negative electrodes has a potential that is approximately 1.5 volts versus a lithium reference electrode.

9. The lithium-ion battery of claim 1, wherein the active material provided on the negative electrodes is a lithium titanate material.

10. The lithium-ion battery of claim 9, wherein the lithium titanate material is Li₄Ti₅O₁₂.

11. The lithium-ion battery of claim 1, wherein the active material provided on the negative electrodes is a lithium titanate material selected from the group consisting of LiTi₂O₄, Li₂TiO₃, Li_xTi_yO₄ where 1.0≦

x≦

1.6 and 1.6≦

y≦

2.0, and combinations thereof.

12. The lithium-ion battery of claim 1, wherein the active material provided on the negative electrodes is selected from the group consisting of TiO₂, WO₂, WO₃, MoO₂, Nb₂O₅, LiWO₂, V₆O₁₃, Li₆Fe₂O₃, LiFeO₂, Fe₂O₃, and combinations thereof.

13. The lithium-ion battery of claim 1, wherein the active material of the positive electrodes has a potential of at least 3 volts versus a lithium reference electrode.

14. The lithium-ion battery of claim 1, wherein the positive electrodes and negative electrodes have a generally rectangular shape.

15. A lithium-ion battery comprising:

an element comprising a plurality of alternating generally planar positive and negative electrodes each having a plurality of edges, the negative electrodes comprising an active material having a potential that is greater than 0.2 volts versus a lithium reference electrode;

wherein the element comprises at least one edge region that comprises edges of the positive electrodes and edges of the negative electrodes;

wherein the active material provided on the negative electrodes does not extend beyond the edges of the positive electrodes in the edge region.

16. The lithium-ion battery of claim 15, wherein the positive electrodes comprise an active material and the area of the positive electrodes covered by active material is not smaller than the area of the negative electrodes covered by active material.

17. The lithium-ion battery of claim 15, wherein the area of the positive electrodes covered by active material is larger than the area of the negative electrodes covered by active material.

18. The lithium-ion battery of claim 15, wherein the edges of the negative electrodes do not extend beyond the edges of the positive electrodes in the edge region.

19. The lithium-ion battery of claim 15, wherein the positive electrodes comprise an active material and the active material of the negative electrodes does not extend beyond the active material of the positive electrodes near the edges of the positive and negative electrodes.

20. The lithium-ion battery of claim 19, wherein the active material of the positive electrodes extends beyond the active material of the negative electrodes near the edges of the positive and negative electrodes.

21. The lithium-ion battery of claim 15, wherein the edges of the positive and negative electrodes in the edge region are generally coplanar.

22. The lithium-ion battery of claim 15, wherein the active material of the negative electrodes has a potential that is greater than 0.3 volts versus a lithium reference electrode.

23. The lithium-ion battery of claim 15, wherein the active material of the negative electrodes has a potential that is approximately 1.5 volts versus a lithium reference electrode.

24. The lithium-ion battery of claim 15, wherein the active material of the negative electrodes is selected from the group consisting of TiO₂, WO₂, W0₃, MoO₂, Nb₂O₅, LiWO₂, V₆O₁₃, Li₆Fe₂O₃, LiFeO₂, Fe₂O₃, a lithium titanate material, and combinations thereof.

25. The lithium-ion battery of claim 24, wherein the active material of the negative electrodes is Li₄Ti₅O₁₂.

26. The lithium-ion battery of claim 24, wherein the active material of the negative electrodes is a lithium titanate material selected from the group consisting of LiTi₂O₄, Li₂TiO₃, Li_xTi_yO₄ where 1.0≦

x≦

1.6 and 1.6≦

y≦

2.0, and combinations thereof.

27. The lithium-ion battery of claim 15, wherein the positive and negative electrodes are generally rectangular.

28. A lithium-ion battery comprising:

a plurality of alternating positive and negative electrodes, the positive and negative electrodes having a generally planar rectangular configuration and comprising a current collector with two opposed surfaces, at least a portion of at least one of the two opposed surfaces for each of the electrodes having an active material provided thereon;

wherein the active material provided on the negative electrodes has a potential that is greater than 0.2 volts versus a lithium reference electrode; and

wherein for at least a plurality of the negative electrodes, the area of the active material is not larger than the area of the active material on an adjacent positive electrode.

29. The lithium-ion battery of claim 28, wherein the active material of the negative electrodes has a potential that is greater than 0.3 volts versus a lithium reference electrode.

30. The lithium-ion battery of claim 28, wherein the active material of the negative electrodes is a lithium titanate material.

31. The lithium-ion battery of claim 30, wherein the lithium titanate material is selected from the group consisting of LiTi₂O₄, Li₂TiO₃, Li_xTi_yO₄ where 1.0≦

x≦

1.6 and 1.6≦

y≦

2.0, Li₄Ti₅O₁₂, and combinations thereof.

32. The lithium-ion battery of claim 28, wherein the active material of the negative electrodes is selected from the group consisting of TiO₂, WO₂, W0₃, MoO₂, Nb₂O₅, LiWO₂, V₆O₁₃, Li₆Fe2O₃, LiFeO₂, Fe₂O₃, and combinations thereof.

33. The lithium-ion battery of claim 28, wherein the active material of the negative electrodes extends to an edge of the negative electrodes but does not extend beyond an edge of an adjacent positive electrode.

34. The lithium-ion battery of claim 28, wherein the active material of the negative electrodes does not extend beyond the active material of an adjacent positive electrode near at least one edge of the electrodes.

35. The lithium-ion battery of claim 28, wherein the current collector of the negative electrode comprises aluminum.