Battery separator

• US 7,914,920 B2
• Filed: 10/09/2003
• Issued: 03/29/2011
• Est. Priority Date: 10/09/2003
• Status: Expired due to Fees

• Current Assignee: Duracell U.S. Operations, Inc. (Berkshire Hathaway Incorporated)
• Original Assignee: Gillette Company (The Procter & Gamble Company)
• Inventors: Boulton, Jonathan M., Davis, Stuart M., Mao, Ou, Eylem, Cahit
• Primary Examiner(s): Ruddock; Ula C.
• Assistant Examiner(s): Echelmeyer; Alix
• Application Number:
  US10/682,740
• Publication Number:
  US 20050079424A1
• Time in Patent Office: 2,728 Days
• Field of Search: None
• US Class Current: 429/144
• CPC Class Codes: H01M 50/417 Polyolefins
• CPC Class Codes: H01M 50/429 Natural polymers
• CPC Class Codes: H01M 50/434 Ceramics
• CPC Class Codes: H01M 50/44 Fibrous material
• CPC Class Codes: H01M 50/451 comprising layers of only organic material and layers containing inorganic material
• CPC Class Codes: H01M 50/457 comprising three or more layers
• CPC Class Codes: H01M 50/489 Separators, membranes, diaphragms or spacing elements inside the cells, characterised by their physical properties, e.g. swelling degree, hydrophilicity or shut down properties
• CPC Class Codes: H01M 6/16 with organic electrolyte H01M6/18 takes precedence
• CPC Class Codes: Y02E 60/10 Energy storage using batteries

Abstract

A battery includes a separator with a trapping layer that traps dissolved metal ions.

Claims

1. A battery, comprising:

a cathode including a cathode active material;

an anode;

an alkaline electrolyte; and

a separator, between the anode and the cathode, comprising a first layer and a second layer,

wherein the first layer comprises a polymeric matrix and metal particles that reduce a metal cation component of an ion generated from the cathode active material and dissolved in the electrolyte surrounded by the polymeric matrix, and the second layer comprises a non-woven material.

2. The battery of claim 1, wherein the dissolved ion is a polyatomic ion.

3. The battery of claim 1, wherein the dissolved ion is a metal cation.

4. The battery of claim 1, wherein the metal has a reduction potential that is more negative than a reduction potential of the metal cation component of the dissolved ion.

5. The battery of claim 4, wherein the metal has a reduction potential that is from about ten millivolts to about 2,100 millivolts negative to the reduction potential of the metal cation component of the dissolved ion.

6. The battery of claim 4, wherein the metal has a reduction potential that is from about 500 millivolts to about 1,500 millivolts negative to the reduction potential of the metal cation component of the dissolved ion.

7. The battery of claim 1, wherein the metal has a reduction potential that is positive to the reduction potential of hydrogen.

8. The battery of claim 1, wherein the metal has a hydrogen gas evolution over potential of from about 500 millivolts to about 750 millivolts measured at a H₂ evolution current density of one mA/cm² in alkaline electrolyte.

9. The battery of claim 1, wherein the metal is bismuth, tin, zinc, or indium.

10. The battery of claim 1, wherein the first polymer matrix comprises a polymer selected from the group consisting of poly(acrylic acid), poly(vinyl alcohol), poly(ethyleneoxide), poly(vinylpyrrolidone), poly(acrylamide), poly(vinyl butyral), and poly(4-styrenesulfonic acid).

11. The battery of claim 1, wherein the first layer further comprises a second material, and the second material traps a product of a reaction between the metal and the dissolved ion.

12. The battery of claim 11, wherein the second material is titanium dioxide or zirconium dioxide.

13. The battery of claim 1, wherein the first layer has a thickness of from about one micron to about 500 microns.

14. The battery of claim 1, wherein a thickness of the first layer is from about 30 percent to about 70 percent of a thickness of the separator.

15. The battery of claim 1, wherein the non-woven material comprises a material selected from the group consisting of polyvinyl alcohol fibers and rayon fibers.

16. The battery of claim 1, wherein the second layer comprises cellophane or grafted polyethylene.

17. The battery of claim 1, wherein the second layer comprises a second material that reduces a metal cation component of a dissolved ion.

18. The battery of claim 1, wherein the first layer contacts the second layer.

19. The battery of claim 1, wherein the first layer is separated from the second layer by at least one other layer.

20. The battery of claim 1, wherein the separator further comprises a third layer.

21. The battery of claim 20, wherein the first layer is disposed between the second layer and the third layer.

22. The battery of claim 20, wherein the second layer comprises cellophane or grafted polyethylene.

23. The battery of claim 22, wherein the third layer comprises cellophane.

24. The battery of claim 22, wherein the third layer comprises grafted polyethylene.

25. The battery of claim 22, wherein the first layer is disposed between the second layer and the third layer.

26. The battery of claim 20, wherein the second layer comprises a non-woven material and the third layer comprises cellophane or grafted polyethylene.

27. The battery of claim 26, wherein the first layer is disposed between the second layer and the third layer.

28. The battery of claim 26, wherein the separator further comprises a fourth layer.

29. The battery of claim 28, wherein the fourth layer comprises a second material that reduces a metal cation component of a dissolved ion.

30. The battery of claim 29, wherein the first layer is disposed between the third layer and the fourth layer.

31. The battery of claim 28, wherein the fourth layer comprises cellophane.

32. The battery of claim 28, wherein the fourth layer comprises grafted polyethylene.

33. The battery of claim 28, wherein the fourth layer contacts the second layer.

34. The battery of claim 28, wherein the fourth layer contacts the first layer.

35. The battery of claim 28, wherein the fourth layer is separated from the first layer by at least one layer.

36. The battery of claim 28, wherein the separator further comprises a fifth layer.

37. The battery of claim 36, wherein the fourth layer comprises cellophane.

38. The battery of claim 36, wherein the fourth layer comprises grafted polyethylene.

39. The battery of claim 36, wherein the fifth layer comprises a second material that reduces a metal cation component of a dissolved ion.

40. The battery of claim 39, wherein the first layer and the fifth layer are disposed between the third layer and the fourth layer.

41. The battery of claim 20, wherein the second layer comprises a second material that reduces a metal cation component of a dissolved ion.

42. The battery of claim 41, wherein the third layer is a non-woven material.

43. The battery of claim 42, wherein the third layer is disposed between the first layer and the second layer.

44. The battery of claim 20, wherein the second layer comprises a second material that sorbs a metal cation component of a dissolved ion.

45. The battery of claim 1, wherein the cathode active material comprises CuO and the dissolved ion comprises Cu(OH)₄²⁻

or Cu(OH)₄³⁻

.

46. The battery of claim 1, wherein the separator further comprises cellophane or grafted polyethylene.

47. The battery of claim 46, wherein a thickness of the cellophane or grafted polyethylene is from about ten percent to about 25 percent of a thickness of the separator.

48. The battery of claim 1, wherein the separator further comprises a non-woven material.

49. The battery of claim 48, wherein the non-woven material comprises polyvinyl alcohol fibers.

50. The battery of claim 48, wherein the non-woven material has a thickness of from about 30 microns to about 120 microns.

51. The battery of claim 48, wherein the non-woven material has a thickness of from about 25 percent to about 60 percent of a thickness of the separator.

52. The battery of claim 1, wherein the second layer is adjacent to the anode.

53. The battery of claim 52, wherein the second layer comprises cellophane or grafted polyethylene.

54. The battery of claim 53, wherein the separator further comprises a third layer.

55. The battery of claim 54, wherein the third layer comprises cellophane.

56. The battery of claim 55, wherein the second layer is adjacent to the anode and the third layer is adjacent to the cathode.

57. The battery of claim 54, wherein the third layer comprises grafted polyethylene.

58. The battery of claim 52, wherein the cathode active material includes a copper material.

59. The battery of claim 52, wherein the cathode active material includes a copper oxide or a copper hydroxide.

60. The battery of claim 59, wherein the cathode active material includes a copper oxide.

61. The battery of claim 1, wherein the cathode active material includes a member selected from the group consisting of ferrates, permanganates, nickel oxide, nickel oxyhydroxide, cobalt oxide, cobalt oxyhydroxide, manganese oxides, or bismuth oxides.

62. The battery of claim 1, wherein the alkaline electrolyte includes potassium hydroxide.

63. The battery of claim 1, wherein the cathode active material includes CuO, the anode includes zinc, the electrolyte includes potassium hydroxide, and the dissolved ion in Cu(OH)₄²⁻

.

64. The battery of claim 1, wherein the polymeric matrix is a solvent and ion permeable gel matrix.

65. The battery of claim 64, wherein the polymer matrix is selected from the group consisting of poly(acrylic acid), poly(vinyl alcohol), poly(ethyleneoxide), poly(vinylpyrrolidone), poly(acrylamide), poly(vinyl butyral), and poly(4-styrenesulfonic acid).

66. The battery of claim 1, wherein the dissolved ion is a polyatomic ion.

67. The battery of claim 66, wherein the polymeric matrix is a solvent and ion permeable gel matrix.

68. The battery of claim 67, wherein the polymer matrix is selected from the group consisting of poly(acrylic acid), poly(vinyl alcohol), poly(ethyleneoxide), poly(vinylpyrrolidone), poly(acrylamide), poly(vinyl butyral), and poly(4-styrenesulfonic acid).

69. A battery, comprising:

a cathode including a cathode active material;

an anode;

an alkaline electrolyte; and

a separator, between the anode and the cathode, comprising a first layer and a second layer wherein the first layer comprises a polymeric matrix and a first material surrounded by the polymer matrix, wherein the first material reduces a metal cation component of an ion generated from the cathode active material and dissolved in the electrolyte, and wherein the first material is not a salt.