Method of producing prelithiated anodes for secondary lithium ion batteries

1. A method of producing a lithium-ion battery anode comprising:

A) Providing an anode active material; wherein said anode active material is selected from the group consisting of:

a) silicon (Si), germanium (Ge), tin (Sn), lead (Pb), antimony (Sb), bismuth (Bi), zinc (Zn), aluminum (Al), and cadmium (Cd);

b) alloys or intermetallic compounds of Si, Ge, Sn, Pb, Sb, Bi, Zn, Al, or Cd with other elements, wherein said alloys or compounds are stoichiometric or non-stoichiometric;

c) oxides, carbides, nitrides, sulfides, phosphides, selenides, and tellurides of Si, Ge, Sn, Pb, Sb, Bi, Zn, Al, Fe, or Cd, and their mixtures or composites; and

d) combinations thereof;

B) Intercalating or absorbing a desired amount of lithium into said anode active material to produce a prelithiated anode active material;

C) Comminuting said prelithiated anode active material into fine particles with an average size less than 10 μm; and

D) Combining multiple fine particles of said prelithiated anode active material with a conductive additive and/or a binder material to form said anode.

2. The method of claim 1 wherein said comminuted, prelithiated fine particles have an average particle size less than 1 μm.

3. The method of claim 1 wherein said comminuted, prelithiated fine particles have an average particle size less than 200 nm.

4. The method of claim 1 wherein said comminuted, prelithiated fine particles have an average particle size less than 100 nm.

5. The method of claim 1 wherein said prelithiated anode active material is produced electrochemically.

6. The method of claim 1 wherein said anode active material is in a fine powder form with an average particle size less than 10 μm; in a thin film form with a thickness less than 10 μm; or in a thin rod form with a transverse dimension less than 10 μm.

7. The method of claim 1 wherein said anode active material is in a fine powder form with an average particle size less than 5 gm.

8. The method of claim 1 wherein said anode active material comprises silicon and said prelithiated particles comprise a prelithiated silicon Li 4 Si, Li 4.4 Si, or Li x Si, wherein numerical x is between 1 and 4.4.

9. The method of claim 1 wherein said comminuted, prelithiated fine particles comprise a prelithiated silicon particle having a size less than 200 nm.

10. The method of claim 1 wherein said step of providing an anode active material comprises providing a doped semiconductor material.

11. The method of claim 1 wherein said step of providing an anode active material comprises providing a doped semiconductor material selected from Si or Ge doped with n -type and/or p-type dopants.

12. The method of claim 1 further comprising a step of coating a surface of said comminuted, prelithiated fine particles with a thin layer of carbon having a thickness less than 1 μm prior to step D).

13. The method of claim 12 wherein said thin layer of carbon has a thickness less than 100 nm.

14. The method of claim 12 wherein said thin layer of carbon is obtained from pyrolization of a polymer, pitch, or organic precursor or obtained by chemical vapor deposition.

15. The method of claim 1 wherein step (d) comprises combining multiple fine particles of said prelithiated anode active material with a conductive additive and/or a binder material, plus a desired amount of another anode active material selected from particles of graphite, hard carbon, soft carbon, meso-carbon micro-bead, surface-modified graphite, carbon-coated graphite, or a combination thereof.

16. The method of claim 1 wherein said conductive additive comprise an electrically conductive material selected from the group consisting of electro-spun nano fibers, carbonized electro-spun nano fibers, vapor-grown carbon or graphite nano fibers, carbon or graphite whiskers, carbon nano-tubes, nano-scaled graphene platelets, metal nano wires, metal-coated nano wires, carbon-coated nano wires, metal-coated nano fibers, carbon-coated nano fibers, and combinations thereof.

17. A method of producing a lithium-ion battery comprising (A) preparing an anode using a method as defined in claim 1 ; and (B) combining said anode with a cathode, separator, and electrolyte to form said battery.

18. A method of producing a lithium-ion battery comprising (A) preparing an anode from pre-lithiated and pre-pulverized particles of claim 1 ; and (B) combining said anode with a cathode, separator, and electrolyte to form said battery.

19. The method as defined in claim 18 , wherein said pre-lithiated and pre-pulverized particles have a size small than 200 nm.