Lithium anodes for electrochemical cells

• US 6,733,924 B1
• Filed: 11/21/2000
• Issued: 05/11/2004
• Est. Priority Date: 11/23/1999
• Status: Expired due to Term

• Current Assignee: Sion Power Corporation
• Original Assignee: Moltech Corporation
• Inventors: Skotheim, Terje A., Sheehan, Christopher J., Mikhaylik, Yuriy V.
• Primary Examiner(s): TSANG FOSTER, SUSY N
• Application Number:
  US09/721,519
• Time in Patent Office: 1,267 Days
• Field of Search: 429/231.95, 429/215
• US Class Current: 429/231.95
• CPC Class Codes: H01M 10/052 Li-accumulators
• 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 4/366 as layered products
• 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 4/58 of inorganic compounds other than oxides or hydroxides, e.g. sulfides, selenides, tellurides, halogenides or LiCoFy; of polyanionic structures, e.g. phosphates, silicates or borates
• CPC Class Codes: H01M 4/5825 Oxygenated metallic salts or polyanionic structures, e.g. borates, phosphates, silicates, olivines
• CPC Class Codes: H01M 4/66 Selection of materials
• CPC Class Codes: H01M 4/661 Metal or alloys, e.g. alloy coatings H01M4/669 take precedence
• CPC Class Codes: H01M 4/663 containing carbon or carbonaceous materials as conductive part, e.g. graphite, carbon fibres
• CPC Class Codes: H01M 4/666 in the form of mixed materials H01M4/668 takes precedence
• CPC Class Codes: H01M 4/667 in the form of layers, e.g. coatings
• CPC Class Codes: Y02E 60/10 Energy storage using batteries

Abstract

Provided are lithium anodes for use in electrochemical cells, where the anode active layer has a first layer comprising lithium metal and a second layer of a temporary protective material, wherein the temporary protective material is a metal capable of forming an alloy with lithium metal or is capable of diffusing into lithium metal. The present invention also pertains to electrochemical cells comprising such anodes.

Claims

1. An anode of an electrochemical cell, wherein said anode comprises:

an anode active layer, which anode active layer comprises;

(i) a first layer comprising lithium metal;

(ii) a second layer of atemporary protective metal in contact with a surface of said first layer; and

(iii) a third layer comprising a single ion conducting layer, wherein said third layer is in contact with said second layer on the side opposite to said first layer and wherein said single ion conducting layer comprises a glass selected from the group consisting of lithium silicates, lithium borates, lithium aluminates, lithium phosphates, lithium phosphorus oxynitrides, lithium silicosulfides, lithium permanosulfides, lithium lanthanum oxides, lithium tantalum oxides, lithium niobium oxides, lithium titanium oxides, lithium borosulfides, lithium aluminosulfides, and lithium phosphosulfides, and combinations thereof.

2. The anode of claim 1, wherein said temporary protective metal is selected from the group consisting of copper, magnesium, aluminum, silver, gold, lead, cadmium, bismuth, indium, germanium, gallium, zinc, tin, and platinum.

3. The anode of claim 1, wherein the thickness of said first layer is 2 to 100 microns.

4. The anode of claim 1, wherein the thickness of said second layer is 5 to 500 nanometers.

5. The anode of claim 1, wherein the thickness of said second layer is 20 to 200 nanometers.

6. The anode of claim 1, wherein said anode further comprises a substrate, wherein said substrate is in contact with a surface of said first layer on the side opposite to said second layer.

7. The anode of claim 6, wherein said substrate comprises a current collector.

8. The anode of claim 6, wherein said substrate is selected from the group consisting of metal foils, polymer films, metallized polymer films, electrically conductive polymer films, polymer films having an electrically conductive coating, electrically conductive polymer films having an electrically conductive metal coating, and polymer films having conductive particles dispersed therein.

9. The anode of claim 1, wherein said anode further comprises a fourth layer, said fourth layer comprising a polymer, and wherein said fourth layer is in contact with said third layer on the side opposite to said second layer.

10. The anode of claim 9, wherein said polymer is selected from the group consisting of electrically conductive polymers, ionically conductive polymers, sulfonated polymers, and hydrocarbon polymers.

11. The anode of claim 9, wherein said polymer is a crosslinked polymer.

12. An electrochemical cell comprising:

(a) a cathode comprising a cathode active material;

(b) an anode; and

(c) a non-aqueous electrolyte interposed between said anode and said cathode;

wherein said anode comprises an anode active layer, which anode active layer comprises;

(i) a first layer comprising lithium metal;

(ii) a second layer of a temporary protective metal in contact with a surface of said first layer; and

(iii) a third layer comprising a single ion conducting layer, wherein said third layer is in contact with said second layer on the side opposite to said first layer and wherein said single ion conducting layer of said third layer comprises a glass selected from the group consisting of lithium silicates, lithium borates, lithium aluminates, lithium phosphates, lithium phosphorus oxynitrides, lithium silicosulfides, lithium permanosulfides, lithium lanthanum oxides, lithium tantalum oxides, lithium niobium oxides, lithium titanium oxides, lithium borosulfides, lithium aluminosulfides, and lithium phosphosulfides, and combinations thereof.

13. The cell of claim 12, wherein said temporary protective metal is selected from the group consisting of copper, magnesium, aluminum, silver, gold, lead, cadmium, bismuth, indium, germanium, gallium, zinc, tin, and platinum.

14. The cell of claim 12, wherein said temporary protective metal is characterized by forming an alloy with, dissolving into, blending with, or diffusing into said lithium metal of said first layer during electrochemical cycling of said cell.

15. The cell of claim 12, wherein said temporary protective metal is characterized by forming an alloy with, dissolving into, blending with, or diffusing into said lithium metal of said first layer prior to electrochemical cycling of the cell.

16. The cell of claim 12, wherein the thickness of said first layer is 2 to 100 microns.

17. The cell of claim 12, wherein the thickness of said second layer is 5 to 500 nanometers.

18. The cell of claim 12, wherein said anode further comprises a substrate, wherein said substrate is in contact with a surface of said first layer on the side opposite to said second layer.

19. The cell of claim 18, wherein said substrate comprises a current collector.

20. The cell of claim 18, wherein said substrate is selected from the group consisting of metal foils, polymer films, metallized polymer films, electrically conductive polymer films, polymer films having an electrically conductive coating, electrically conductive polymer films having an electrically conductive metal coating, and polymer films having conductive particles dispersed therein.

21. The cell of claim 12, wherein said anode further comprises a fourth layer, said fourth layer comprising a polymer, and wherein said fourth layer is in contact with said third layer on the side opposite to said second layer.

22. The cell of claim 21, wherein said polymer is selected from the group consisting of electrically conductive polymers, ionically conductive polymers, sulfonated polymers, and hydrocarbon polymers.

23. The cell of claim 21, wherein said polymer is a crosslinked polymer.

24. The cell of claim 12, wherein said electrolyte is selected from the group consisting of liquid electrolytes, solid polymer electrolytes and gel polymer electrolytes.

25. The cell of claim 12, wherein said electrolyte comprises a separator selected from the group consisting of polyolefin separators and microporous xerogel layer separators.

26. The cell of claim 12, wherein said cathode active material comprises one or more materials selected from the group consisting of electroactive metal chalcogenides, electroactive conductive polymers, and electroactive sulfur-containing materials, and combinations thereof.

27. The cell of claim 12, wherein said cathode active material comprises elemental sulfur.

28. The cell of claim 12, wherein said cathode active material comprises an electroactive sulfur-containing organic polymer, wherein said sulfur-containing organic polymer, in its oxidized state, comprises one or more polysulfide moieties, —

S_m—

, where m is an integer equal to or greater than 3.

29. The cell of claim 12, wherein said cathode active material comprises an electroactive sulfur-containing organic polymer, wherein said sulfur-containing organic polymer, in its oxidized state, comprises one or more polysulfide moieties, —

S_m⁻

, where m is an integer equal to or greater than 3.

30. The cell of claim 12, wherein said cathode active material comprises an electroactive sulfur-containing organic polymer, wherein said sulfur-containing organic polymer, in its oxidized state, comprises one or more polysulfide moieties, S_m²⁻

, where m is an integer equal to or greater than 3.

31. The cell of claim 12, wherein said cell is a secondary cell.

32. The cell of claim 12, wherein said cell is a primary cell.