Graphene-enhanced anode particulates for lithium ion batteries

Patent metadata

Field	Value
Publication number	US-9558860-B2
Application number	US-80763510-A
Country	US
Kind code	B2
Filing date	Sep 10, 2010
Priority date	Sep 10, 2010
Publication date	Jan 31, 2017
Grant date	Jan 31, 2017

Abstract

A nano graphene-enhanced particulate for use as a lithium-ion battery anode active material, wherein the particulate is formed of a single sheet of graphene or a plurality of graphene sheets and a plurality of fine anode active material particles with a size smaller than 10 μm. The graphene sheets and the particles are mutually bonded or agglomerated into the particulate with at least a graphene sheet embracing the anode active material particles. The amount of graphene is at least 0.01% by weight and the amount of the anode active material is at least 0.1% by weight, all based on the total weight of the particulate. A lithium-ion battery having an anode containing these graphene-enhanced particulates exhibits a stable charge and discharge cycling response, a high specific capacity per unit mass, a high first-cycle efficiency, a high capacity per electrode volume, and a long cycle life.

First claim

The invention claimed is:

1. A lithium-ion battery anode comprising:
multiple nano graphene-enhanced particulates, wherein at least one of said particulate is formed of a single or a plurality of graphene sheets and a plurality of fine anode active material particles with a size smaller than 10 μm, and the graphene sheets and the particles are mutually bonded or agglomerated into said particulate with at least a graphene sheet embracing inside an envelope constituted by the graphene sheet or multiple graphene sheets said anode active material particles and said a single or plurality of graphene sheets, and wherein said graphene sheets are in an amount of at least 0.01% but less than 99% by weight and said anode active material is in an amount of at least 0.1% by weight, all based on the total weight of said particulate.

2. The anode of claim 1 wherein the graphene amount is at least 0.1% by weight.

3. The anode of claim 1 wherein the graphene amount is at least 1% by weight.

4. The anode of claim 1 wherein said particulate is spherical or ellipsoidal in shape.

5. The anode of claim 1 wherein said graphene comprises single-layer graphene or few-layer graphene, wherein said few-layer graphene is defined as a graphene platelet formed of less than 10 graphene planes.

6. The anode of claim 1 , wherein said anode active material comprises Sn or Si as a primary element with Si or Sn content no less than 20% by weight based on the total weight of the anode active material.

7. The anode of claim 1 , wherein said anode active material comprises an element selected from Si, Ge, Sn, Cd, Sb, Pb, Bi, Zn, Al, Co, Ni, or Ti.

8. The anode of claim 1 , wherein said anode active material is selected from the group consisting of:
(g) silicon (Si), germanium (Ge), tin (Sn), lead (Pb), antimony (Sb), bismuth (Bi), zinc (Zn), aluminum (Al), titanium (Ti), nickel (Ni), cobalt (Co), and cadmium (Cd);
(h) alloys or intermetallic compounds of Si, Ge, Sn, Pb, Sb, Bi, Zn, Al, Ti, Ni, Co, or Cd with other elements, wherein said alloys or compounds are stoichiometric or non-stoichiometric;
(i) oxides, carbides, nitrides, sulfides, phosphides, selenides, and tellurides of Si, Ge, Sn, Pb, Sb, Bi, Zn, Al, Ti, Fe, Ni, Co, or Cd, and their mixtures, composites, or lithium-containing composites;
(j) salts and hydroxides of Sn;
(k) lithium titanate, lithium manganate, lithium aluminate, lithium-containing titanium oxide, lithium transition metal oxide; and
(l) combinations thereof.

9. The anode of claim 1 , wherein said anode active material particles in a particulate have a dimension smaller than 1 μm.

10. The anode of claim 1 , wherein said anode active material particles in a particulate have a dimension smaller than 100 nm.

11. The anode of claim 1 , further comprising a carbon or graphite material in electronic contact with said anode active material and a graphene sheet.

12. The anode of claim 1 , further comprising a carbon or graphite material coated on or in contact with at least one of said anode active material particles, wherein said carbon or graphite material is selected from polymeric carbon, amorphous carbon, chemical vapor deposition carbon, coal tar pitch, petroleum pitch, meso-phase pitch, carbon black, coke, acetylene black, activated carbon, fine expanded graphite particle with a dimension smaller than 100 nm, artificial graphite particle, natural graphite particle, or a combination thereof.

13. The anode of claim 12 , wherein said polymeric carbon or amorphous carbon is obtained from pyrolyzation of a polymer selected from the group consisting of phenol-formaldehyde, polyacrylonitrile, styrene-based polymers, cellulosic polymers, epoxy resins, and combinations thereof.

14. The anode of claim 1 , wherein said anode active material is selected from lithiated titanium dioxide, lithiated titanium oxide, lithium titanate, or Li 4 Ti 5 O 12 .

15. The anode of claim 1 wherein said anode active material is selected from natural graphite, artificial graphite, meso-carbon micro-bead (MCMB), graphitic coke, meso-phase carbon, hard carbon, soft carbon, polymeric carbon, carbon or graphite fiber segments, carbon nano-fiber or graphitic nano-fiber, carbon nano-tube, or a combination thereof.

16. A lithium ion battery comprising an anode of claim 1 , a cathode, a separator disposed between the anode and the cathode, and electrolyte in physical contact with both the anode and the cathode.

17. A lithium ion battery of claim 16 , wherein said cathode comprises a graphene-enhanced cathode particulate formed of a single or a plurality of graphene sheets and a plurality of fine cathode active material particles with a size smaller than 10 μm, and the graphene sheets and the particles are mutually bonded or agglomerated into said cathode particulate with at least a graphene sheet embracing said cathode active material particles, and wherein said graphene is in an amount of from 0.01% to 30% by weight based on the cathode particulate weight.

18. The lithium ion battery of claim 17 , wherein said cathode active material particles have a size smaller than 1 μm.

19. The lithium ion battery of claim 17 , wherein said cathode active material particles have a size smaller than 100 nm.

20. The lithium ion battery of claim 17 , wherein said cathode active material is selected from the group consisting of lithium cobalt oxide, lithium nickel oxide, lithium manganese oxide, lithium vanadium oxide, lithium-mixed metal oxide, lithium iron phosphate, lithium manganese phosphate, lithium vanadium phosphate, lithium mixed metal phosphates, metal sulfides, and combinations thereof.

21. A lithium ion battery comprising an anode of claim 12 , a cathode, a separator disposed between the anode and the cathode, and electrolyte in physical contact with both the anode and the cathode.

22. A lithium ion battery comprising an anode of claim 14 , a cathode, a separator disposed between the anode and the cathode, and electrolyte in physical contact with both the anode and the cathode.

23. A process for producing the anode of claim 1 , said process comprising:
(a) Preparing a precursor mixture of graphene or graphene precursor with an anode active material or anode active material precursor;
(b) Thermally and/or chemically converting said precursor mixture to said graphene-enhanced anode particulate; and
(c) Combining multiple particulates prepared in step (b) and a binder material to form an anode.

24. The process of claim 23 , wherein said step of preparing a precursor mixture comprises preparing a suspension of graphene or graphene precursor in a liquid medium and mixing an anode active material or anode active material precursor in said suspension to form a multi-component suspension.

25. The process of claim 24 , wherein the process further comprises a step of drying said multi-component suspension to form said precursor mixture.

26. The process of claim 24 , wherein the process further comprises a step of drying said multi-component suspension to form said precursor mixture using a spray-drying, spray-pyrolysis, fluidized-bed drying, or atomization or aerosolizing step.

27. The process of claim 23 , wherein said step of converting comprises a sintering, heat-treatment, spray-pyrolysis, or fluidized bed drying or heating procedure.

28. The process of claim 23 , wherein said step of converting comprises a procedu

Assignees

• Zhamu Aruna
• Shi Jinjun
• Chen Guorong
• Fang Qing
• Jang Bor Z
• Samsung Electronics Co Ltd

Inventors

• Zhamu Aruna
• Shi Jinjun
• Chen Guorong
• Fang Qing
• Jang Bor Z

Classifications

• H01M4/5825

  Oxygenated metallic salts or polyanionic structures, e.g. borates, phosphates, silicates, olivines · CPC title

• H01M4/387

  Tin or alloys based on tin · CPC title

• H01M4/483

  for non-aqueous cells (H01M4/485 takes precedence) · CPC title

• H01M4/0471

  involving thermal treatment, e.g. firing, sintering, backing particulate active material, thermal decomposition, pyrolysis · CPC title

• H01M4/386

  Silicon or alloys based on silicon · CPC title