NEGATIVE ACTIVE MATERIAL FOR RECHARGEABLE LITHIUM BATTERY AND RECHARGEABLE LITHIUM BATTERY INCLUDING SAME

• US 20110281180A1
• Filed: 05/03/2011
• Published: 11/17/2011
• Est. Priority Date: 05/14/2010
• Status: Active Grant

• Current Assignee: Samsung SDI Company Limited
• Original Assignee: Samsung SDI Company Limited
• Inventors: Park, Se-Ho, Choi, Hyun-Jun, Kim, Dong-Yung, Kim, Bong-Chull, Hwang, Cheol-Hee
• Granted Patent: US 9,876,221 B2
• Time in Patent Office: Days
• US Class Current: 429/338
• 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 10/0567 characterised by the additives
• CPC Class Codes: H01M 4/133 Electrodes based on carbonaceous material, e.g. graphite-intercalation compounds or CFx
• CPC Class Codes: H01M 4/134 Electrodes based on metals, Si or alloys
• CPC Class Codes: H01M 4/362 Composites
• CPC Class Codes: H01M 4/386 Silicon or alloys based on silicon
• CPC Class Codes: H01M 4/587 for inserting or intercalating light metals
• CPC Class Codes: Y02E 60/10 Energy storage using batteries

Abstract

Embodiments of the present invention are directed to negative active materials for lithium rechargeable batteries and to lithium rechargeable batteries including the negative active materials. The negative active material includes a crystalline carbon material having pores, and amorphous conductive nanoparticles in the pores, on the surface of the crystalline carbon, or both in the pores and on the surface of the crystalline carbon. The conductive nanoparticles have a FWHM of about 0.35 degrees (°) or greater at the crystal plane that produces the highest peak as measured by X-ray diffraction.

Claims

1. A negative active material for a rechargeable lithium battery, comprising a carbon-nanoparticle composite comprising:

a crystalline carbon material having pores; and

amorphous conductive nanoparticles having a full width at half maximum of about 0.35°

or greater at a crystal plane producing the highest peak as measured by X-ray diffraction, wherein at least some of the amorphous conductive nanoparticles are in the pores of the crystalline carbon, or on a surface of the crystalline carbon, or both in the pores and on the surface of the crystalline carbon.

2. The negative active material of claim 1, wherein the crystalline carbon comprises a material selected from the group consisting of natural graphite, artificial graphite, and combinations thereof.

3. The negative active material of claim 1, wherein the crystalline carbon has a porosity of about 15% to about 50%.

4. The negative active material of claim 1, wherein the amorphous conductive nanoparticles comprise a material selected from the group consisting of:

Si;

Si—

X alloys wherein X is not Si and is selected from the group consisting of alkaline metals, alkaline earth metals, group 13 elements, group 14 elements, group 15 elements, group 16 elements, transition elements, rare earth elements, and combinations thereof;

Sn;

Sn—

X′

alloys wherein X′

is not Sn and is selected from the group consisting of alkaline metals, alkaline earth metals, group 13 elements, group 14 elements, group 15 elements, group 16 elements, transition elements, rare earth elements, and combinations thereof;

Pb;

In;

As;

Sb;

Ag; and

combinations thereof.

5. The negative active material of claim 1, wherein the amorphous conductive nanoparticles comprise silicon nanoparticles having a full width at half maximum at a (111) plane of about 0.35°

or greater as measured by X-ray diffraction.

6. The negative active material of claim 1, wherein the amorphous conductive nanoparticles have an average particle diameter of about 50 nm to about 200 nm.

7. The negative active material of claim 1, wherein the amorphous conductive nanoparticles are present in the negative active material in an amount of about 5 to about 25 parts by weight based on 100 parts by weight of the crystalline carbon material.

8. The negative active material of claim 1, further comprising amorphous carbon at least partially surrounding the carbon-nanoparticle composite.

9. The negative active material of claim 8, wherein the amorphous carbon is in at least one pore of the crystalline carbon material.

10. The negative active material of claim 9, wherein the amorphous carbon is between a surface of the crystalline carbon and at least one of the amorphous conductive nanoparticles.

11. The negative active material of claim 8, wherein the amorphous carbon comprises a material selected from the group consisting of soft carbon, hard carbon, a mesophase pitch carbonized product, baked coke, and combinations thereof.

12. The negative active material of claim 8, wherein the amorphous carbon is present in the negative active material in an amount of about 5 to about 25 parts by weight based on 100 parts by weight of the crystalline carbon material.

13. The negative active material of claim 1, wherein the crystalline carbon material comprises fine powders having a particle size of about 1 μ

m to about 5 μ

m.

14. The negative active material of claim 1, wherein the negative active material has an average particle diameter ranging from about 5 to about 40 μ

m.

15. A method of manufacturing a negative active material, comprising:

providing conductive nanoparticles by milling conductive particles using beads having an average particle diameter of about 50 to about 150 μ

m for about 24 hours or longer; and

mixing the conductive nanoparticles with a crystalline carbon material having pores to provide a carbon-nanoparticle composite.

16. The method of claim 15, wherein the beads comprise a material selected from the group consisting of metal oxide beads, metal nitride beads, metal carbide beads, and combinations thereof.

17. The method of claim 15, wherein the beads comprise a material selected from the group consisting of zirconia beads, alumina beads, silicon carbide beads, silica beads, and combinations thereof.

21. The rechargeable lithium battery of claim 16, wherein the amorphous conductive nanoparticles comprise a material selected from the group consisting of:

Si;

Si—

X alloys wherein X is not Si and is selected from the group consisting of alkaline metals, alkaline earth metals, group 13 elements, group 14 elements, group 15 elements, group 16 elements, transition elements, rare earth elements, and combinations thereof;

Sn;

Sn—

X′

alloys wherein X′

is not Sn and is selected from the group consisting of alkaline metals, alkaline earth metals, group 13 elements, group 14 elements, group 15 elements, group 16 elements, transition elements, rare earth elements, and combinations thereof;

Pb;

In;

As;

Sb;

Ag; and

combinations thereof.

18. A rechargeable lithium battery, comprising:

a negative electrode comprising a negative active material comprising;

a crystalline carbon material having pores, and

amorphous conductive nanoparticles having a full width at half maximum of about 0.35°

or greater at a crystal plane producing the highest peak as measured by X-ray diffraction, wherein at least some of the amorphous conductive nanoparticles are in the pores of the crystalline carbon material, or on a surface of the crystalline carbon material, or both in the pores and on the surface of the crystalline carbon material;

a positive electrode comprising a positive active material; and

a non-aqueous electrolyte.

19. The rechargeable lithium battery of claim 18, wherein the crystalline carbon comprises a material selected from the group consisting of natural graphite, artificial graphite, and combinations thereof.

20. The rechargeable lithium battery of claim 18, wherein the crystalline carbon has a porosity of about 15% to about 50%.

22. The rechargeable lithium battery of claim 18, wherein the amorphous conductive nanoparticles have an average particle diameter of about 50 nm to about 200 nm.

23. The rechargeable lithium battery of claim 18, wherein the amorphous conductive nanoparticles are present in the negative active material in an amount of about 5 to about 25 parts by weight based on 100 parts by weight of the crystalline carbon material.

24. The rechargeable lithium battery of claim 18, further comprising amorphous carbon at least partially surrounding the carbon-nanoparticle composite.

25. The rechargeable lithium battery of claim 24, wherein the amorphous carbon comprises a material selected from the group consisting of soft carbon, hard carbon, a mesophase pitch carbonized product, baked coke, and combinations thereof.

26. The rechargeable lithium battery of claim 24, wherein the amorphous carbon is present in the negative active material in an amount of about 5 to about 25 parts by weight based on 100 parts by weight of the crystalline carbon.

27. The rechargeable lithium battery of claim 18, wherein the non-aqueous electrolyte comprises a non-aqueous organic solvent and a lithium salt, wherein the non-aqueous organic solvent comprises a material selected from the group consisting of vinylene carbonate, ethylene carbonate based compounds represented by Formula 2, and combinations thereof:

28. The rechargeable lithium battery of claim 27, wherein the material selected from the group consisting of vinylene carbonate, ethylene carbonate based compounds represented by Formula 2, and combinations thereof is present in the electrolyte in an amount of about 15 to about 30 volume % based on a total volume of the non-aqueous organic solvent.