Particulate electrode including electrolyte for a rechargeable lithium battery

• US 20020031706A1
• Filed: 07/17/2001
• Published: 03/14/2002
• Est. Priority Date: 07/31/2000
• Status: Active Grant

• Current Assignee: Electrovaya Incorporated
• Original Assignee: Electrovaya Incorporated
• Inventors: Bhola, Rakesh, Dasgupta, Sankar, Jacobs, James K.
• Granted Patent: US 6,815,121 B2
• Time in Patent Office: Days
• US Class Current: 429/212
• 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 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 4/131 Electrodes based on mixed oxides or hydroxides, or on mixtures of oxides or hydroxides, e.g. LiCoOx
• CPC Class Codes: H01M 4/133 Electrodes based on carbonaceous material, e.g. graphite-intercalation compounds or CFx
• CPC Class Codes: H01M 4/505 of mixed oxides or hydroxides containing manganese for inserting or intercalating light metals, e.g. LiMn2O4 or LiMn2OxFy
• CPC Class Codes: H01M 4/525 of mixed oxides or hydroxides containing iron, cobalt or nickel for inserting or intercalating light metals, e.g. LiNiO2, LiCoO2 or LiCoOxFy
• CPC Class Codes: H01M 4/621 Binders
• CPC Class Codes: H01M 6/188 Processes of manufacture
• CPC Class Codes: Y02E 60/10 Energy storage using batteries
• CPC Class Codes: Y10T 29/49108 Electric battery cell making
• CPC Class Codes: Y10T 29/49115 including coating or impregnating

Abstract

A matted particulate electrode located between the current collector and a porous separator of a rechargeable lithium battery is described, which contains electro-active particles intermixed with pliable, solid, lithium ion conducting, polymer electrolyte filaments having adhesive surfaces. The electro-active particles and the optionally added electro-conductive carbon particles adhere to the tacky surface of the adhesively interlinking polymer electrolyte filaments. The matted particulate electrode is impregnated with an organic solution containing another lithium compound. In a second embodiment the porous separator is coated on at least one of its faces, with polymer electrolyte having an adhesive surface and made of the same polymer as the electrolyte filaments. The polymer electrolyte filaments in the matted layer may adhere to the coated surface of the separator. In addition the polymer coating is partially filling the pores of the porous electrolyte, but leaving sufficient space in the pores for the organic solution to penetrate the separator of the lithium battery.

Claims

1. A particulate electrode for a rechargeable lithium battery having a current collector and an inert, porous polymer separator, comprising,

a mixture of electro-active particles intermixed with pliable, solid, ion conducting, polymer filaments having adhesive surfaces and containing a first dissociable lithium compound, wherein said pliable, solid, ion conducting, polymer filaments having adhesive surfaces are adhesively interlinked, and said electro-active particles are adhering to said surface of said pliable, solid, ion conducting, polymer filaments, thereby forming a matted layer held adhesively together, said matted layer having voids which are capable of being impregnated with a non-aqueous solution containing a second dissociable lithium compound, and said matted layer being located between a current collector and an inert, porous polymer separator.

2. A particulate electrode for a rechargeable lithium battery having a current collector and an inert, porous polymer separator, as claimed in claim 1, wherein said pliable, solid, ion conducting, polymer filaments have a length and a cross-sectional diameter less than 1 μ

m, and the ratio of said cross-sectional diameter of said pliable, solid, ion conducting, polymer filaments to said length ranges between 1;

5 and 1;

100.

3. A particulate electrode for a rechargeable lithium battery having a current collector and an inert, porous polymer separator, as claimed in claim 1, wherein said electro-active particles are additionally intermixed with fine carbon in an amount less than 7 wt. %.

4. A particulate electrode for a rechargeable lithium battery having a current collector and an inert, porous polymer separator, as claimed in claim 1, wherein said pliable, solid, ion conducting, polymer filaments having adhesive surfaces are made of at least one of the polymers selected from the group consisting of an oxide of polyolefin polymers and polyvinylidene fluoride copolymers.

5. A particulate electrode for a rechargeable lithium battery having a current collector and an inert, porous polymer separator, as claimed in claim 1, wherein said first dissociable lithium compound is the same as said second dissociable lithium compound.

6. A particulate electrode for a rechargeable lithium battery having a current collector and an inert, porous polymer separator, as claimed in claim 1, wherein said first dissociable lithium compound is different from said second dissociable lithium compound.

7. A particulate electrode for a rechargeable lithium battery having a current collector and an inert, porous polymer separator, as claimed in claim 1, wherein said first dissociable lithium compound and said second lithium compound is selected from the group consisting of lithium perchlorate (LiClO₄), lithium borofluoride (LiBF₄), lithium phosphofluoride (LiPF₆), lithium arsenofluoride, (LiAsF₆), lithium antimony-fluoride (LiSbF₆) and lithium triflate (LiCF₃SO₃).

8. A particulate electrode for a rechargeable lithium battery having a current collector and an inert, porous polymer separator, as claimed in claim 1, wherein said non-equeous solution comprises an organic carbonate or a mixture of organic carbonates.

9. A particulate electrode for a rechargeable lithium battery having a current collector and an inert, porous polymer separator, as claimed in claim 1, wherein said inert, porous polymer separator has two opposing faces.

10. A particulate electrode for a rechargeable lithium battery having a current collector and an inert, porous polymer separator, as claimed in claim 1, wherein said inert, porous polymer separator has a multiplicity of layers.

11. A particulate electrode for a rechargeable lithium battery having a current collector and an inert, porous polymer separator, as claimed in claim 1, wherein said inert, porous polymer separator has a pair of opposing faces, and at least one of said opposing faces is coated with a porous, solid, ion conducting, polymer coating comprising the same polymer as said pliable, solid, ion conducting, polymer filaments.

12. A particulate electrode for a rechargeable lithium battery having a current collector and an inert, porous polymer separator, as claimed in claim 11, wherein said porous, solid, ion conducting, polymer coating on at least one of said opposing faces of said inert, porous polymer separator is additionally coating the walls of the pores of said inert, porous polymer separator, thereby yielding partially filled pores.

13. A particulate electrode for a rechargeable lithium battery having a current collector and an inert, porous polymer separator, as claimed in claim 11, wherein said pliable, solid ion conducting polymer filaments comprised in said particulate mixture are capable of being adhesively attached to said porous, solid, ion conducting, polymer coating on at least one of said opposing faces of said inert, porous polymer separator.

14. A particulate electrode for a rechargeable lithium battery having a current collector and an inert, porous polymer separator, as claimed in claim 1, wherein said electro-active particles in said mixture are negative-active particles capable of reversibly intercalating lithium ions.

15. A particulate electrode for a rechargeable lithium battery having a current collector and an inert, porous polymer separator, as claimed in claim 14, wherein said negative-active particles are carbonaceous particles capable of reversibly intercalating lithium.

16. A particulate electrode for a rechargeable lithium battery having a current collector and an inert, porous polymer separator, as claimed in claim 1, wherein said electro-active particles are positive-active particles capable of reversibly intercalating lithium ions.

17. A particulate electrode for a rechargeable lithium battery having a current collector and an inert, porous polymer separator, as claimed in claim 16, wherein said positive-active particles are selected from the group consisting of:

particles of lithiated transition metal oxides, particles of lithiated solid solution of transition metal oxides, and particles of lithiated transition metal sulphides.

19. A rechargeable lithium battery as claimed in claim 18, wherein said pliable, solid, ion conducting, polymer filaments having adhesive surfaces are made of at least one of the polymers selected from the group consisting of an oxide of polyolefin polymers and polyvinylidene fluoride copolymers.

20. A rechargeable lithium battery as claimed in claim 18, wherein said first dissociable lithium compound is the same as said second dissociable lithium compound.

21. A rechargeable lithium battery as claimed in claim 18, wherein said first dissociable lithium compound is different from said second dissociable lithium compound.

22. A rechargeable lithium battery as claimed in claim 18, wherein said inert, porous polymer separator has a multiplicity of layers.

23. A rechargeable lithium battery as claimed in claim 18, wherein said negative active particles in said first mixture are carbonaceous particles capable of reversibly intercalating lithium.

24. A rechargeable lithium battery as claimed in claim 18, wherein said positive active particles in said second mixture are selected from the group consisting of:

particles of lithiated transition metal oxides, particles of lithiated solid solution of transition metal oxides, and particles of lithiated transition metal sulphides.

25. A rechargeable lithium battery as claimed in claim 24, wherein said positive active particles are additionally intermixed with fine carbon in an amount less than 7 wt. %.

27. A rechargeable lithium battery as claimed in claim 26, wherein said porous, solid, ion conducting polymer coating on at least one of said opposing faces of said inert, porous polymer separator is additionally coating the walls of the pores of said inert, porous polymer separator, thereby yielding partially filled pores.

28. A rechargeable lithium battery as claimed in claim 26, wherein said pliable, solid, ion conducting, polymer filaments having adhesive surfaces are made of at least one of the polymers selected from the group consisting of an oxide of polyolefin polymers and polyvinylidene fluoride copolymers.

29. A rechargeable lithium battery as claimed in claim 26, wherein said first dissociable lithium compound is the same as said second dissociable lithium compound.

30. A rechargeable lithium battery as claimed in claim 26, wherein said first dissociable lithium compound is different from said second dissociable lithium compound.

31. A rechargeable lithium battery as claimed in claim 26, wherein said pliable, solid ion conducting polymer filaments comprised in said first and said second particulate mixture are capable of being adhesively attached to said porous, solid, ion conducting, polymer coating on at least one of said opposing faces of said inert, porous polymer separator.

32. A rechargeable lithium battery as claimed in claim 26, wherein said inert, porous polymer separator has a multiplicity of layers.

33. A rechargeable lithium battery as claimed in claim 26, wherein said negative active particles in said first mixture are carbonaceous particles capable of reversibly intercalating lithium.

34. A rechargeable lithium battery as claimed in claim 26, wherein said positive active particles in said second mixture are selected from the group consisting of:

particles of lithiated transition metal oxides, particles of lithiated solid solution of transition metal oxides, and particles of lithiated transition metal sulphides.

35. A rechargeable lithium battery as claimed in claim 34, wherein said positive active particles are additionally intermixed with fine carbon in an amount less than 7 wt. %.

37. A method of assembling a particulate electrode for a rechargeable lithium battery having a current collector and an inert, porous, polymer separator, as claimed in claim 36, wherein electron conducting fine carbon particles are additionally admixed with said electro-active particles.

18. A rechargeable lithium battery comprising:

i) a current collector for a negative electrode;

ii) a particulate negative electrode comprising a first mixture of negative active particles intermixed with pliable, solid, ion conducting, polymer filaments having adhesive surfaces and containing a first dissociable lithium compound, wherein said pliable, solid, ion conducting, polymer filaments having adhesive surfaces are adhesively interlinked, and said negative active particles are adhering to said surface of said pliable, solid, ion conducting, polymer filaments, thereby forming a matted layer held adhesively together, said matted layer having voids which are capable of being impregnated with a non-aqueous solution containing a second dissociable lithium compound, and said matted layer being located adjacent said current collector for said negative electrode;

iii) an inert, porous polymer separator; and

iv) a particulate positive electrode comprising a second mixture of positive active particles intermixed with pliable, solid, ion conducting, polymer filaments having adhesive surfaces and containing a first dissociable lithium compound, wherein said pliable, solid, ion conducting, polymer filaments having adhesive surfaces are adhesively interlinked, and said positive active particles are adhering to said surface of said pliable, solid, ion conducting polymer filaments, thereby forming a matted layer held adhesively together, said matted layer having voids which are capable of being impregnated with a non-aqueous solution containing a second dissociable lithium compound and said matted layer being located between said inert, porous polymer separator, and a current collector for said positive electrode.

26. A rechargeable lithium battery comprising:

i) a current collector for a negative electrode;

ii) a particulate negative electrode comprising a first mixture of negative active particles intermixed with pliable, solid, ion conducting, polymer filaments having adhesive surfaces and containing a first dissociable lithium compound, wherein said pliable, solid, ion conducting polymer filaments having adhesive surfaces are adhesively interlinked, and said negative active particles are adhering to said surface of said pliable, solid, ion conducting, polymer filaments, thereby forming a matted layer held adhesively together, said matted layer having voids which are capable of being impregnated with a non-aqueous solution containing a second dissociable lithium compound, and said matted layer being located adjacent said current collector for said negative electrode;

iii) an inert, porous polymer separator, wherein said inert, porous polymer separator has a pair of opposing faces, and at least one of said opposing faces is coated with a porous, solid, ion conducting, polymer coating comprising the same polymer as said pliable, solid, ion conducting, polymer filaments; and

iv) a particulate positive electrode comprising a second mixture of positive active particles intermixed with pliable, solid, ion conducting, polymer filaments having adhesive surfaces and containing a first dissociable lithium compound, wherein said pliable, solid, ion conducting polymer filaments having adhesive surfaces are adhesively interlinked, and said positive active particles are adhering to said surface of said pliable, solid, ion conducting, polymer filaments, thereby forming a matted layer held adhesively together, said matted layer having voids which are capable of being impregnated with a non-aqueous solution containing a second dissociable lithium compound and said matted layer being located between said inert, porous polymer separator, and a current collector for said positive electrode.

36. A method of assembling a particulate electrode for a rechargeable lithium battery having a current collector and an inert, porous, polymer separator, comprising the steps of:

i) providing pliable, solid, ion conducting, polymer filaments having adhesive surfaces, containing a first dissociable lithium compound, and having aspect ratio ranging between 1;

5 and 1;

100;

ii) providing electro-active particles and mixing said electro-active particles with said pliable, solid, ion conducting, polymer filaments containing a first dissociable lithium compound and having adhesive surfaces, thereby obtaining a matted layer of electro-active particles adhering to said pliable, solid, ion conducting, polymer filaments, said matted layer having voids;

iii) placing the matted layer so obtained between said current collector and said inert, porous, polymer separator, and;

iv) subsequently, impregnating said matted layer with a non-aqueous, organic solution containing a second dissociable lithium compound.