HIGH ENERGY HIGH POWER ELECTRODES AND BATTERIES

• US 20090246636A1
• Filed: 03/25/2009
• Published: 10/01/2009
• Est. Priority Date: 03/25/2008
• Status: Active Application

• Current Assignee: A123 Systems Incorporated
• Original Assignee: A123 Systems Incorporated
• Inventors: Wixom, Michael, Jang, Young-Il, Chiang, Yet-Ming, Chu, Andrew C.
• Granted Patent: US 9,299,966 B2
• Time in Patent Office: Days
• US Class Current: 429/231.950
• CPC Class Codes: H01M 10/052 Li-accumulators
• CPC Class Codes: H01M 10/0585 of accumulators having only flat construction elements, i.e. flat positive electrodes, flat negative electrodes and flat 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 4/139 Processes of manufacture
• CPC Class Codes: H01M 4/64 Carriers or collectors
• CPC Class Codes: H01M 50/446 Composite material consisting of a mixture of organic and inorganic materials
• CPC Class Codes: H01M 50/46 Separators, membranes or diaphragms characterised by their combination with electrodes
• 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

Subassemblies for use in an electrochemical device are provided, as are processes for preparing the subassemblies and electrochemical cells incorporating the subassemblies. In some embodiments, the subassemblies include (a) a first electrode and (b) a separator or a first current collector or both. The first electrode is bonded to the separator or the first current collector or both. In some embodiments, the subassemblies further include a second electrode and a second current collector. In some embodiments, the electrodes or separators are sintered. Bipolar cells are also provided, including a plurality of stacked electrochemical cells that are joined in series. The positive electrode and the negative electrode of each stack include a sintered electrode.

Claims

1. A subassembly for use in an electrochemical device comprising

(a) a first electrode and

(b) a separator or a first current collector or both,

wherein the first electrode is bonded to the separator or the first current collector or both.

2. The subassembly of claim 1, wherein the first electrode is thermally bonded to the separator or the first current collector or both.

3. The subassembly of claim 1, wherein the subassembly is a sintered subassembly.

4. The subassembly of claim 1, wherein the first current collector and the separator are bonded to opposite surfaces of the first electrode.

5. The subassembly of claim 1, wherein the separator comprises an organic compound, an inorganic-organic composite or blend, an inorganic compound, a particulate material, or a sintered particulate ceramic.

6. The subassembly of claim 1, wherein the first electrode comprises a layered oxide, a metal fluoride, or a lithium-transition metal phosphate compound, which optionally includes a dopant metal.

7. The subassembly of claim 4, wherein the first current collector is primarily confined to the perimeter of the first electrode.

8. The subassembly of claim 7, wherein the perimeter area of the portion of the first electrode that is bonded to the first current collector is less than about 50% of the total area of the first electrode.

9. The subassembly of claim 1, comprising a first electrode and a separator, further comprising a second electrode, wherein the first and second electrodes are bonded to opposite surfaces of the separator.

10. The subassembly of claim 9, wherein the first electrode, the second electrode or both comprises a sintered electrode.

11. The subassembly of claim 4, further comprising a second electrode, wherein the second electrode is bonded to the separator.

12. The subassembly of claim 4, further comprising a second electrode and a second current collector, wherein the second electrode and the first electrode have a thermal bond to opposite surfaces of the separator and wherein the second current collector and the separator are bonded to opposite surfaces of the second electrode.

13. The subassembly of claim 12, wherein the first electrode is a positive electrode, the second electrode is a negative electrode, the first current collector is a positive current collector and the second current collector is a negative current collector.

14. The subassembly of claim 1, wherein the thickness of the subassembly is at least about 200 μ

m.

15. The subassembly of claim 1, wherein the density of the subassembly is at least about 65% of theoretical.

16. A subassembly for use in an electrochemical device comprising

(a) a first sintered electrode and

(b) a sintered separator or a first current collector or both,

wherein the first sintered electrode is bonded to the sintered separator or the first current collector or both.

17. The subassembly of claim 16, wherein the first sintered electrode is thermally bonded to the sintered separator or the first current collector or both.

18. The subassembly of claim 16, wherein the subassembly is a sintered subassembly.

19. The subassembly of claim 16, wherein the first sintered current collector and the sintered separator are bonded to opposite surfaces of the first sintered electrode.

20. The subassembly of claim 16, wherein the separator comprises an organic compound, an inorganic-organic composite or blend, an inorganic compound, a particulate material, or a sintered particulate ceramic.

21. The subassembly of claim 16, wherein the first sintered electrode comprises a layered oxide, a metal fluoride, or a lithium-transition metal phosphate compound, which optionally includes a dopant metal.

22. The subassembly of claim 19, wherein the first sintered current collector is primarily confined to the perimeter of the first sintered electrode.

23. The subassembly of claim 22, wherein the perimeter area of the portion of the first sintered electrode that is bonded to the first current collector is less than about 50% of the total area of the first sintered electrode.

24. The subassembly of claim 16, comprising a first sintered electrode and a sintered separator, further comprising a second sintered electrode, wherein the first and second sintered electrodes are bonded to opposite surfaces of the sintered separator.

25. The subassembly of claim 19, further comprising a second sintered electrode, wherein the second sintered electrode is bonded to the sintered separator.

26. The subassembly of claim 19, further comprising a second sintered electrode and a second current collector, wherein the second sintered electrode and the first sintered electrode have a thermal bond to opposite surfaces of the sintered separator and wherein the second current collector and the sintered separator are bonded to opposite surfaces of the second sintered electrode.

27. The sub-assembly of claim 26, wherein the first sintered electrode is a positive electrode, the second sintered electrode is a negative electrode, the first current collector is a positive current collector and the second current collector is a negative current collector.

28. The subassembly of claim 16, wherein the thickness of the subassembly is at least about 200 μ

m.

29. The subassembly of claim 16, wherein the density of the subassembly is at least about 65% of theoretical.

30. A subassembly for use in an electrochemical device comprising

(a) a first electrode and

(b) a separator or a first current collector or both,

wherein the subassembly is produced by

(i) combining the first electrode with the separator or the first current collector or both and

(ii) heating the first electrode and the separator or the first current collector or both under conditions effective to form a sintered sub-assembly.

31. The subassembly of claim 30, wherein the first electrode is thermally bonded to the separator or the first current collector or both.

32. The subassembly of claim 30, wherein the first electrode comprises a sintered electrode.

33. The subassembly of claim 30, wherein the separator comprises a sintered separator.

34. The subassembly of claim 30, wherein the heating step comprises heating the first electrode, the separator and the first current collector to form a sintered subassembly.

35. The subassembly of claim 34, wherein each of the first current collector and the separator is thermally bonded to opposite surfaces of the first electrode.

36. The subassembly of claim 35, wherein the first current collector is primarily confined to the perimeter of the first electrode.

37. The subassembly of claim 36, wherein the perimeter area of the portion of the first electrode that is bonded to the first current collector is less than about 30% of the total area of the first electrode.

38. The subassembly of claim 30, comprising a first electrode and a separator, further comprising a second electrode, wherein the first and second electrodes are bonded to opposite surfaces of the separator.

39. The subassembly of claim 38, wherein the first electrode, the second electrode or both comprises a sintered electrode.

40. The subassembly of claim 35, further comprising a second electrode, wherein the second electrode is bonded to the separator.

41. The subassembly of claim 30, further comprising a second electrode and a second current collector, wherein the second electrode and the first electrode are heated with the separator, the first current collector, and the second current collector to form a sintered subassembly

42. The subassembly of claim 41, wherein the first electrode is a positive electrode, the second electrode is a negative electrode, the first current collector is a positive current collector and the second current collector is a negative current collector.

43. The subassembly of claim 30, wherein the separator comprises an organic compound, an inorganic-organic composite or blend, an inorganic compound, a particulate material, or a sintered particulate ceramic.

44. The subassembly of claim 30, wherein the first electrode comprises a layered oxide, a metal fluoride, or a lithium-transition metal phosphate compound, which optionally includes a dopant metal.

45. The subassembly of claim 30, wherein the thickness of the subassembly is at least about 200 μ

m.

46. The subassembly of claim 30, wherein the density of the subassembly is at least about 65% of theoretical.

47. A subassembly for use in an electrochemical device comprising

(a) a first sintered electrode and

(b) a sintered separator or a first current collector or both,

wherein the subassembly is produced by

(i) combining the first sintered electrode with the sintered separator or the first current collector or both, and

(ii) heating the first sintered electrode and the sintered separator or the first current collector or both under conditions effective to form a sintered sub-assembly.

49. The subassembly of claim 47, comprising both a first current collector and a sintered separator, wherein the heating step comprises heating the first sintered electrode, the sintered separator and the first current collector to form a sintered subassembly.

50. The subassembly of claim 49, wherein each of the first current collector and the sintered separator is thermally bonded to opposite surfaces of the first sintered electrode.

51. The subassembly of claim 49, wherein the first current collector is primarily confined to the perimeter of the first sintered electrode.

52. The subassembly of claim 51, wherein the perimeter area of the portion of the first sintered electrode that is bonded to the first current collector is less than about 30% of the total area of the first sintered electrode.

53. The subassembly of claim 47, comprising a first sintered electrode and a sintered separator, further comprising a second sintered electrode, wherein the first and second sintered electrodes are bonded to opposite surfaces of the sintered separator.

54. The subassembly of claim 50, further comprising a second sintered electrode, wherein the second sintered electrode is bonded to the sintered separator.

55. The subassembly of claim 54, further comprising a second sintered electrode and a second current collector, wherein the second sintered electrode and the first sintered electrode are heated with the sintered separator, the first current collector, and the second current collector to form a sintered subassembly.

56. The subassembly of claim 55, wherein the first sintered electrode is a positive electrode, the second sintered electrode is a negative electrode, the first current collector is a positive current collector and the second current collector is a negative current collector.

57. The subassembly of claim 47, wherein the sintered separator comprises an organic compound, an inorganic-organic composite or blend, an inorganic compound, a particulate material, or a sintered particulate ceramic.

58. The subassembly of claim 47, wherein the first sintered electrode comprises a layered oxide, a metal fluoride, or a lithium-transition metal phosphate compound, which optionally includes a dopant metal.

59. The subassembly of claim 47, wherein the thickness of the subassembly is at least about 200 μ

m.

60. The subassembly of claim 47, wherein the density of the subassembly is at least about 65% of theoretical.

48. The subassembly of claim 48, wherein the first sintered electrode is thermally bonded to the sintered separator or the first current collector.

61. An electrochemical device comprising:

(a) a positive electrode in electronic contact with a positive electrode current collector, the positive current collector in electrical connection with an external circuit;

(b) a negative electrode in electronic contact with a negative electrode current collector, the negative current collector in electrical connection with an external circuit;

(c) a separator positioned between the positive electrode and the negative electrode; and

(d) an electrolyte in ionic contact with the positive and negative electrodes;

wherein the positive electrode or the negative electrode and the separator comprise a sintered subassembly.

62. The electrochemical device of claim 61, wherein the mass fraction of inactive materials in the device is less than about 50%.

63. The electrochemical device of claim 61, wherein the specific energy of the device is greater than about 300 Wh/kg at a power density of greater than about 600 W/kg.

75. The process of claim 61, wherein the sintered separator comprises an organic compound, an inorganic-organic composite or blend, an inorganic compound, a particulate material, or a sintered particulate ceramic.

76. The process of claim 61, wherein the first sintered electrode comprises a layered oxide, a metal fluoride, or a lithium-transition metal phosphate compound, which optionally includes a dopant metal.

64. A process for preparing subassembly for use in an electrochemical device comprising:

(a) combining a first electrode with a separator or a first current collector or both; and

(b) heating the first electrode and the separator or the first current collector under conditions effective to form a sintered subassembly.

65. The process of claim 64 wherein the process produces a thermal bond between the first electrode and the separator or the first current collector or both.

66. The process of claim 64, wherein the first electrode comprises a sintered electrode.

67. The process of claim 64, wherein the separator comprises a sintered separator.

68. The process of claim 64, wherein the heating step comprises heating the first electrode, the separator and the first current collector to form a sintered subassembly.

69. The process of claim 64, wherein a second electrode is combined with the first electrode and the separator, wherein the process produces a bond between first and second electrodes and opposite surfaces of the separator.

70. The process of claim 69, wherein the second electrode comprises a sintered electrode.

71. The process of claim 69, wherein a second electrode is combined with the first electrode and the separator, and wherein the process produces a bond between the second electrode and the separator.

72. The process of claim 71, wherein the second electrode comprises a sintered electrode.

73. The process of claim 68, wherein the combining step further comprises combining a second electrode and a second current collector with the first electrode, the first current collector and the separator, and wherein the heating step comprises heating the second electrode and the first electrode with the separator, the first current collector, and the second current collector to form a sintered subassembly.

74. The process of claim 73, wherein the first electrode is a positive electrode, the second electrode is a negative electrode, the first current collector is a positive current collector and the second current collector is a negative current collector.

77. A biopolar cell, comprising a plurality of stacked electrochemical cells, wherein the electrochemical cells are joined in series and wherein each of said stacked electrochemical cells comprises:

(a) a positive electrode in electronic contact with a positive electrode current collector, the positive current collector in electrical connection with an external circuit;

(b) a negative electrode in electronic contact with a negative electrode current collector, the negative current collector in electrical connection with an external circuit;

(c) a separator positioned between the positive electrode and the negative electrode; and

(d) an electrolyte in ionic contact with the positive and negative electrodes;

wherein the positive electrode and the negative electrode of each stack comprise a sintered electrode.

78. The bipolar cell of claim 77, wherein the separator comprises a sintered separator.

79. The bipolar cell of claim 77, wherein (a) the separator and (b) the positive electrode or the negative electrode or both are bonded.

80. The bipolar cell of claim 77, wherein (a) the positive electrode and (b) the separator or the positive current collector or both are bonded.

81. The bipolar cell of claim 77, wherein (a) the negative electrode and (b) the separator or the negative current collector or both are bonded.

82. The bipolar cell of claim 77, wherein the positive current collector, the positive electrode, the separator, the negative electrode and the negative current collector are bonded.

83. The bipolar cell of claim 77, wherein (a) the positive electrode and (b) the separator or the positive current collector or both comprise a sintered subassembly.

84. The bipolar cell of claim 77, wherein (a) the negative electrode and (b) the separator or the negative current collector or both comprise a sintered subassembly.

85. The bipolar cell of claim 77, wherein the positive current collector, the positive electrode, the separator, the negative electrode, and the negative current collector comprise a sintered subassembly.

86. The bipolar cell of claim 77, wherein the positive electrode or the negative electrode formed from a sintered ceramic is at least about 200 μ

m mm in thickness.

87. The bipolar cell of claim 77, wherein the sintered subassembly is at least about 200 μ

m in thickness.

88. The bipolar cell of claim 77, wherein the cell further comprises a redox shuttle.

89. The secondary cell of claim 77, wherein the electrolyte comprises an electroactive additive.

90. The bipolar cell of claim 77, wherein the separator comprises an electroactive polymer, wherein the electroactive polymer forms a percolating pathway through the separator.

91. The bipolar cell of claim 77, wherein the thickness of the positive electrode or the negative electrode formed from a sintered ceramic varies by less than 25% from the mean thickness.