COATED OR TREATED MICROPOROUS BATTERY SEPARATORS, RECHARGEABLE LITHIUM BATTERIES, SYSTEMS, AND RELATED METHODS OF MANUFACTURE AND/OR USE

• US 20160329541A1
• Filed: 05/05/2016
• Published: 11/10/2016
• Est. Priority Date: 05/08/2015
• Status: Active Grant

• Current Assignee: Celgard LLC (Asahi Kasei Corporation)
• Original Assignee: Celgard LLC (Asahi Kasei Corporation)
• Inventors: Reinartz, Stefan, Adams, Changqing Wang, Wensley, C. Glen
• Granted Patent: US 10,741,814 B2
• Time in Patent Office: Days
• US Class Current: 1/1
• CPC Class Codes: H01M 10/0525 Rocking-chair batteries, i.e. batteries with lithium insertion or intercalation in both electrodes; Lithium-ion batteries
• CPC Class Codes: H01M 4/5825 Oxygenated metallic salts or polyanionic structures, e.g. borates, phosphates, silicates, olivines
• CPC Class Codes: H01M 50/403 Manufacturing processes of separators, membranes or diaphragms
• CPC Class Codes: H01M 50/417 Polyolefins
• CPC Class Codes: H01M 50/44 Fibrous material
• CPC Class Codes: H01M 50/454 comprising a non-fibrous layer and a fibrous layer superimposed on one another
• 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 50/494 Tensile strength
• CPC Class Codes: Y02E 60/10 Energy storage using batteries

Abstract

In accordance with at least certain embodiments, the present invention is directed to novel, improved, coated, or treated separator membranes, separators or membrane based separators for lithium batteries. The membranes or separators may include non-woven layers, improved surfactant treatments, or combinations thereof. The separators or membranes are useful for solvent electrolyte lithium batteries, especially rechargeable lithium ion batteries, and provide improved performance, wettability, cycling ability, and/or recharging efficiency.

Claims

1. A microporous battery separator for a lithium battery, comprising:

a) a polyolefin layer; and

b) at least one non-woven layer on each side of the polyolefin layer, and wherein the separator has at least one of enhanced puncture strength and reduced shrinkage compared to just the polyolefin layer alone.

2. The separator according to claim 1, wherein the polyolefin layer comprises at least one membrane of polypropylene.

3. The separator according to claim 1, wherein the non-woven layer comprises polypropylene.

4. The separator according to claim 1, wherein the nonwoven layer comprises a non-woven layer having a melting point less than about 200°

C.

5. The separator according to claim 1, further comprising a surfactant coating or treatment.

6. The separator according to claim 5, wherein the surfactant comprises a lithium salt.

7. The separator according to claim 5, wherein the surfactant comprises a fluorine-containing surfactant.

8. The separator according to claim 5, wherein the surfactant is present in an amount (weight add-on) from about 0.1-10.0%.

20. In a lithium battery, the improvement comprising the separator of claim 1.

28. An energy storage system comprising one or more LiFePO₄ batteries comprising a separator according to claim 1.

9. A microporous battery separator for a lithium battery, comprising:

a polyolefin layer; and

at least one non-woven layer on at least one side of the polyolefin layer, and wherein the separator has at least one surfactant coating or treatment therein or thereon to enhance wettability of a solvent based electrolyte.

10. The separator according to claim 9, wherein the polyolefin layer comprises at least one membrane of polyethylene, polypropylene, or a combination, blend or mixture thereof .

11. The separator according to claim 9, wherein the polyolefin layer comprises multiple layers of polyethylene, multiple layers of polypropylene, or multiple layers of polyethylene and polypropylene.

12. The separator according to claim 11, wherein the polyolefin layer is selected from one of the following multilayer arrangements:

PE/PE, PP/PP, PE/PP, PP/PE/PP, PE/PP/PE, PE/PE/PE, PP/PP/PP, PE/PE/PE/PE, PP/PP/PP/PP, PE/PP/PP/PE, PP/PE/PE/PP, PE/PE/PE/PE/PE, PP/PP/PP/PP/PP, PE/PE/PP/PE/PE, PP/PP/PE/PP/PP, PP/PE/PP/PE/PP, PE/PP/PE/PP/PE, PE/PE/PE/PE/PE/PE, PP/PP/PP/PP/PP/PP, PE/PE/PP/PP/PE/PE, PP/PP/PE/PE/PP/PP, PP/PE/PP/PP/PE/PP, PE/PP/PE/PE/PP/PE, PP/PE/PE/PE/PE/PP, and PE/PP/PP/PP/PP/PE.

13. The separator according to claim 9, wherein the non-woven layer comprising polypropylene, polyethylene, low density polyethylene, polycarbonate, polyethylene terephthalate, polybutylene terephthalate, polymethylpentene, polystyrene, polyamide, polyimide, nylon, or a combination, blend or mixture thereof.

14. The separator according to claim 9, wherein the non-woven layer having a melting point less than about 200°

C.

15. The separator according to claim 9, comprising a surfactant treatment on the surface thereof.

16. The separator according to claim 9, wherein the surfactant comprises a lithium salt.

17. The separator according to claim 9, wherein the surfactant comprises a fluorine-containing surfactant.

18. The separator according to claim 9, wherein the surfactant is present in an amount (weight add-on) from about 0.1-10.0%.

21. In a lithium battery, the improvement comprising the separator of claim 9.

29. An energy storage system comprising one or more LiFePO₄ batteries comprising a separator according to claim 9.

19. A method of making a battery separator, comprising laminating at least one non-woven layer to at least one face of a polyolefin layer to form a composite, and treating the composite with at least one surfactant to enhance the wettability of a solvent based electrolyte.

22. In a lithium battery, the improvement comprising the separator of claim 19.

23. A lithium battery, comprising at least one cell including electrodes, electrolyte, and a separator between the electrodes, the separator comprising:

(a) a polyolefin layer; and

a non-woven layer, and wherein the separator or electrolyte comprising at least one surfactant coating, treatment or material, wherein the surfactant comprises fluorine atoms, lithium atoms, or both.

24. The battery of claim 23, wherein the polyolefin layer comprises one or more layers, wherein the polyolefin is selected from the group consisting of polypropylene, polyethylene, polymethylpentene, copolymers, blends, combinations, and mixtures thereof, and wherein:

said surfactant coating, treatment or material comprising an alkali metal salt of a linear or branched alkylbenzene sulfonate acid, a lithium salt of a linear or branched alkylbenzene sulfonate acid, a nonionic fluorosurfactant, a nonionic fluorosurfactant that repels water, or a lithium 4-dodecylbenzenesulfonate, and wherein said battery is a secondary lithium ion battery.

25. The battery of claim 24, wherein said separator wets by an organic or inorganic electrolyte in less than 20 seconds.

26. An energy storage system comprising one or more lithium batteries according to claim 25.

27. An energy storage system comprising one or more LiFePO₄ batteries according to claim 23.

30. The battery of claim 24, wherein said separator wets by an organic or inorganic electrolyte in less than 5 seconds.

31. A microporous lithium battery separator membrane, comprising:

at least one polyolefin layer; and

at least one surfactant coating or treatment therein or thereon to enhance wettability of the membrane by a solvent based electrolyte.

32. The separator membrane according to claim 31, wherein the polyolefin layer comprises at least one membrane of polyethylene, polypropylene, or both.

33. The separator membrane according to claim 31, wherein the polyolefin layer comprises multiple layers of polyethylene, multiple layers of polypropylene, or multiple layers of polyethylene and polypropylene.