Stabilized anode for lithium-polymer batteries

• US 5,961,672 A
• Filed: 07/07/1997
• Issued: 10/05/1999
• Est. Priority Date: 02/16/1994
• Status: Expired due to Term

• Current Assignee: Moltech Corporation
• Original Assignee: Moltech Corporation
• Inventors: Soloveichik, Grigorii L., Skotheim, Terje A., Gavrilov, Alexei B.
• Primary Examiner(s): Maples, John S.
• Application Number:
  US08/889,202
• Time in Patent Office: 820 Days
• Field of Search: 29/623.5, 429/192, 429/306, 429/303, 429/324
• US Class Current: 29/623.5
• CPC Class Codes: H01M 10/052 Li-accumulators
• CPC Class Codes: H01M 10/0565 Polymeric materials, e.g. gel-type or solid-type
• 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 50/414 Synthetic resins, e.g. thermoplastics or thermosetting resins
• 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: Y02T 10/70 Energy storage systems for electromobility, e.g. batteries
• CPC Class Codes: Y10T 29/49115 including coating or impregnating

Abstract

The invention relates to thin film solid state electrochemical cells consisting of a lithium metal anode, a polymer electrolyte and a cathode, where the lithium anode has been stabilized with a polymer film capable of transmitting lithium ions. Methods for making battery cells using the anode stabilizing films of the invention are disclosed.

Claims

1. A method for making a battery cell, said method comprising:

(a) providing a lithium anode having a lithium surface;

(b) providing a non-aqueous organic electrolyte containing a dissolved lithium salt;

(c) depositing on said lithium surface an anode stabilizing film, wherein said anode stabilizing film is deposited by vacuum deposition using a monomeric or oligomeric starting material, and wherein said anode stabilizing film has a chemical structure which is different than the chemical structure of said monomeric or oligomeric starting material; and

,

(d) providing a cathode comprising a cathode active material;

wherein;

said anode stabilizing film is interposed between said lithium anode and said electrolyte; and

,

said electrolyte is interposed between said anode stabilizing film and said cathode.

2. The method of claim 1, wherein said anode stabilizing film has a thickness in the range of 0.01 to 10 micrometers.

3. The method of claim 1, wherein said anode stabilizing film has a thickness in the range of 0.01 to 0.1 micrometers.

4. The method of claim 1, wherein said anode stabilizing film has a thickness in the range of 0.1 to 5.0 micrometers.

5. The method of claim 1, wherein said anode stabilizing film is deposited on said lithium surface by vacuum deposition using a monomeric starting material, and wherein said monomeric starting material is acetylene.

6. The method of claim 5, wherein said anode stabilizing film is deposited at a temperature of 25°

C. or greater.

7. The method of claim 5, wherein said anode stabilizing film is deposited at a temperature of 100°

C. or greater.

8. The method of claim 1, wherein said anode stabilizing film is deposited on said lithium surface by plasma-assisted vacuum evaporation.

9. The method of claim 1, wherein said anode stabilizing film is deposited on said lithium surface by vacuum deposition using a conjugated oligomeric starting material.

10. The method of claim 9, wherein said conjugated oligomeric starting material is selected from the group consisting of:

poly(p-phenylene), polyacetylene, poly(phenylene vinylene), polyazulene, poly(perinaphthalene), polyacenes, and poly(naphthalene-2,6-diyl).

11. The method of claim 1, wherein said electrolyte is a non-aqueous liquid electrolyte containing a dissolved lithium salt.

12. The method of claim 1, wherein said electrolyte is a polymer electrolyte containing a dissolved lithium salt.

13. The method of claim 12, wherein said polymer electrolyte is a single-ion conducting polymer electrolyte.

14. The method of claim 12, wherein said polymer electrolyte is a gel polymer electrolyte.

15. The method of claim 1, wherein said lithium salt is selected from the group consisting of:

LiClO₄, LiAsF₆, LiSO₃ CF₃, LiSO₃ CH₃, LiBF₄, LiB(Ph)₄, LiPF₆, LiC(SO₂ CF₃)₃, LiN(SO₂ CF₃)₂, and lithium salts of fluorosulfonated phenols and pyrroles.

16. The method of claim 1, wherein said cathode comprises a cathode active material selected from the group consisting of:

inorganic insertion oxides, inorganic insertion sulfides, organo-sulfur compounds and conjugated polymers.

17. The method of claim 1, wherein said cathode active material comprises elemental sulfur.

18. The method of claim 16, wherein said cathode active material comprises an organ-sulfur compound.

19. The method of claim 1, wherein said battery cell further comprises a current collector for said anode, a separate current collector for said cathode and suitable encapsulation to prevent the penetration of air and moisture.

20. A method for making a battery cell, said method comprising:

(a) providing a lithium anode having a lithium surface;

(b) providing a non-aqueous organic electrolyte containing a dissolved lithium salt;

(c) depositing on said lithium surface an electrically conducting crosslinked polymer film by vacuum deposition using a monomeric or oligomeric starting material, and wherein said polymer film has a chemical structure which is different than the chemical structure of said monomeric or oligomeric starting material; and

,

(d) providing a cathode comprising a cathode active material;

wherein;

said polymer film is interposed between said lithium anode and said electrolyte;

said electrolyte is interposed between said polymer film and said cathode; and

,

said polymer film is capable of transmitting lithium ions between said lithium anode and said electrolyte.

21. The method of claim 20, wherein said electrically conducting crosslinked polymer film is deposited on said lithium surface by plasma-assisted vacuum evaporation.

22. The method of claim 20, wherein said electrically conducting crosslinked polymer film is deposited on said lithium surface using a conjugated oligomeric starting material.

23. The method of claim 22, wherein said conjugated oligomeric starting material is selected from the group consisting of:

poly(p-phenylene), polyacetylene, poly(phenylene vinylene), polyazulene, poly(perinaphthalene), polyacenes, and poly(naphthalene-2,6-diyl).

24. The method of claim 20, wherein said electrolyte is a non-aqueous liquid electrolyte containing a dissolved lithium salt.

25. The method of claim 20, wherein said electrolyte is a polymer electrolyte containing a dissolved lithium salt.

26. The method of claim 25, wherein said polymer electrolyte is a single-ion conducting polymer electrolyte.

27. The method of claim 25, wherein said polymer electrolyte is a gel polymer electrolyte.

28. The method of claim 20, wherein said lithium salt is selected from the group consisting of:

LiClO₄, LiAsF₆, LiSO₃ CF₃, LiSO₃ CH₃, LiBF₄, LiB(Ph)₄, LiPF₆, LiC(SO₂ CF₃)₃, LiN(SO₂ CF₃)₂, and lithium salts of fluorosulfonated phenols and pyrroles.

29. The method of claim 20, wherein said cathode comprises a cathode active material selected from the group consisting of:

inorganic insertion oxides, inorganic insertion sulfides, organo-sulfur compounds and conjugated polymers.

30. The method of claim 20, wherein said cathode active material comprises elemental sulfur.

31. The method of claim 29, wherein said cathode active material comprises an organo-sulfur compound.

32. The method of claim 20, wherein said battery cell further comprises a current collector for said anode, a separate current collector for said cathode and suitable encapsulation to prevent the penetration of air and moisture.

33. A method for making a battery cell, said method comprising:

(a) providing a lithium anode having a lithium surface;

(b) providing a non-aqueous organic electrolyte containing a dissolved lithium salt;

(c) depositing on said lithium surface a lithium ion conducting polymer film by vacuum deposition using a monomeric or oligomeric starting material, and wherein said polymer film has a chemical structure which is different than the chemical structure of said monomeric or oligomeric starting material; and

,

(d) providing a cathode comprising a cathode active material;

wherein;

said polymer film is interposed between said lithium anode and said electrolyte;

said electrolyte is interposed between said polymer film and said cathode; and

,

said polymer film is doped electrically conductive by incorporation of lithium ions, is capable of transmitting lithium ions between said lithium anode and said electrolyte, is capable of stabilizing said lithium anode against formation of dendrites, is capable of dissolving dendrites, and is capable of stabilizing said lithium anode against reaction with said electrolyte to form a more resistive interfacial layer.

34. The method of claim 33, wherein said lithium ion conducting polymer film is deposited on said lithium surface using a monomeric starting material, and said monomeric starting material is acetylene.

35. The method of claim 33, wherein said lithium ion conducting polymer film is deposited on said lithium surface by plasma-assisted vacuum evaporation.

36. The method of claim 33, wherein said lithium ion conducting polymer film is deposited on said lithium surface using a conjugated oligomeric starting material.

37. The method of claim 36, wherein said conjugated oligomeric starting material is selected from the group consisting of:

poly(p-phenylene), polyacetylene, poly(phenylene vinylene), polyazulene, poly(perinaphthalene), polyacenes, and poly(naphthalene-2,6-diyl).

38. The method of claim 33, wherein said electrolyte is a non-aqueous liquid electrolyte containing a dissolved lithium salt.

39. The method of claim 33, wherein said electrolyte is a polymer electrolyte containing a dissolved lithium salt.

40. The method of claim 39, wherein said polymer electrolyte is a single-ion conducting polymer electrolyte.

41. The method of claim 39, wherein said polymer electrolyte is a gel polymer electrolyte.

42. The method of claim 33, wherein said lithium salt is selected from the group consisting of:

LiClO₄, LiAsF₆, LiSO₃ CF₃, LiSO₃ CH₃, LiBF₄, LiB(Ph)₄, LiPF₆, LiC(SO₂ CF₃)₃, LiN(SO₂ CF₃)₂, and lithium salts of fluorosulfonated phenols and pyrroles.

43. The method of claim 33, wherein said cathode comprises a cathode active material selected from the group consisting of:

inorganic insertion oxides, inorganic insertion sulfides, organo-sulfur compounds and conjugated polymers.

44. The method of claim 33, wherein said cathode active material comprises elemental sulfur.

45. The method of claim 43, wherein said cathode active material comprises an organo-sulfur compound.

46. The method of claim 33, wherein said battery cell further comprises a current collector for said anode, a separate current collector for said cathode and suitable encapsulation to prevent the penetration of air and moisture.

47. A method for making a battery cell, said method comprising:

(a) providing a lithium anode;

(b) providing a non-aqueous polymer electrolyte containing a dissolved lithium salt and having an electrolyte surface;

(c) depositing on said electrolyte surface an electrically conducting crosslinked polymer film by vacuum deposition using a monomeric or oligomeric starting material, and wherein said polymer film has a chemical structure which is different than the chemical structure of said monomeric or oligomeric starting material; and

,

(d) providing a cathode comprising a cathode active material;

wherein;

said polymer film is interposed between said lithium anode and said electrolyte;

said electrolyte is interposed between said polymer film and said cathode; and

,

said polymer film is capable of transmitting lithium ions between said lithium anode and said electrolyte.

48. The method of claim 47, wherein said electrically conducting crosslinked polymer film is deposited on said electrolyte surface by plasma-assisted vacuum evaporation.

49. The method of claim 47, wherein said electrically conducting crosslinked polymer film is deposited on said electrolyte surface using a conjugated oligomeric starting material.

50. The method of claim 49, wherein said conjugated oligomeric starting material is selected from the group consisting of:

poly(p-phenylene), polyacetylene, poly(phenylene vinylene), polyazulene, poly(perinaphthalene), polyacenes, and poly(naphthalene-2,6-diyl).

51. A method for making a battery cell, said method comprising:

(a) providing a lithium anode;

(b) providing a non-aqueous polymer electrolyte containing a dissolved lithium salt and having an electrolyte surface;

(c) depositing on said electrolyte surface a lithium ion conducting polymer film by vacuum deposition using a monomeric or oligomeric starting material, and wherein said polymer film has a chemical structure which is different than the chemical structure of said monomeric or oligomeric starting material; and

,

(d) providing a cathode comprising a cathode active material;

wherein;

said polymer film is interposed between said lithium anode and said electrolyte;

said electrolyte is interposed between said polymer film and said cathode; and

,

said polymer film is doped electrically conductive by incorporation of lithium ions, is capable of transmitting lithium ions between said lithium anode and said electrolyte, is capable of stabilizing said lithium anode against formation of dendrites, is capable of dissolving dendrites, and is capable of stabilizing said lithium anode against reaction with said electrolyte to form a more resistive interfacial layer.

52. The method of claim 51, wherein said lithium ion conducting polymer film is deposited on said electrolyte surface by plasma-assisted vacuum evaporation.

53. The method of claim 51, wherein said lithium ion conducting polymer film is deposited on said electrolyte surface using a conjugated oligomeric starting material.

54. The method of claim 53, wherein said conjugated oligomeric starting material is selected from the group consisting of:

poly(p-phenylene), polyacetylene, poly(phenylene vinylene), polyazulene, poly(perinaphthalene), polyacenes, and poly(naphthalene-2,6-diyl).

55. The method of claim 51, wherein said lithium ion conducting polymer film is deposited on said electrolyte surface using a monomeric starting material, and said monomeric starting material is acetylene.