Process for preparing electroactive materials for metal-ion batteries

Patent metadata

Field	Value
Publication number	US-12203165-B2
Application number	US-202418444891-A
Country	US
Kind code	B2
Filing date	Feb 19, 2024
Priority date	Dec 21, 2018
Publication date	Jan 21, 2025
Grant date	Jan 21, 2025

Abstract

The disclosure relates to a process for preparing particulate materials having high electrochemical capacities that are suitable for use as anode active materials in rechargeable metal-ion batteries. In one aspect, the disclosure provides a process for preparing a particulate material comprising a plurality of composite particles. The process includes providing particulate porous carbon frameworks comprising micropores and/or mesopores, wherein the porous carbon frameworks have a D 50 particle diameter of at least 20 μm; depositing an electroactive material selected from silicon and alloys thereof into the micropores and/or mesopores of the porous carbon frameworks using a chemical vapour infiltration process in a fluidised bed reactor, to provide intermediate particles; and comminuting the intermediate particles to provide said composite particles.

First claim

The invention claimed is:

1. A process for preparing composite particles, the process comprising:
(a) providing particulate porous carbon frameworks comprising micropores and/or mesopores, wherein the porous carbon frameworks have a D 50 particle diameter of at least 20 μm;
(b) depositing an electroactive material selected from silicon, tin, aluminium, germanium and alloys thereof into the micropores and/or mesopores of the porous carbon frameworks using chemical vapour infiltration while the porous carbon frameworks are in a fluidized state, to provide intermediate particles;
(c) comminuting the intermediate particles to provide said composite particles; and
(d) depositing a conductive coating on the composite particles from step (c) to produce coated composite particles.

2. The process according to claim 1 , wherein the conductive coating is a carbon-based conductive coating.

3. The process according to claim 2 , wherein the carbon-based conductive coating is obtained by chemical vapour deposition.

4. The process according to claim 2 , wherein the carbon-based conductive coating is formed by depositing a solution of carbon-containing compound onto the surface of the particulate material followed by pyrolysis.

5. The process according to claim 1 , wherein the conductive coating has a thickness of 2 to 30 nm.

6. The process according to claim 1 , wherein the BET surface area of the coated composite particles after step (d) is less than 50 m 2 /g.

7. The process according to claim 1 , further comprising transferring the intermediate particles into a comminuting device prior to step (c).

8. The process according to claim 1 , wherein the electroactive material is silicon.

9. The process according to claim 4 , wherein the intermediate particles, the composite particles, and the coated composite particles comprise a plurality of nanoscale electroactive domains located within the micropores and/or mesopores of the porous carbon frameworks.

10. The process according to claim 1 , wherein the chemical vapour infiltration process comprises contacting the porous carbon frameworks with a silicon-containing precursor.

11. The process according to claim 10 , wherein the silicon-containing precursor gas is selected from the group consisting of silane (SiH 4 ), disilane (Si 2 H 6 ), trisilane (Si 3 H 8 ), tetrasilane (Si 4 H 10 ), chlorosilanes such as trichlorosilane (HSiCl 3 ), methylchlorosilanes such as methyltrichlorosilane (CH 3 SiCl 3 ) or dimethyldichlorosilane ((CH 3 ) 2 SiCl 2 ), preferably wherein the silicon-containing precursor gas is silane.

12. The process according to claim 1 , wherein the chemical vapour infiltration process is performed at a temperature in the range from 200 to 1,250° C.

13. The process according to claim 12 , wherein the chemical vapour infiltration process is performed at a temperature in the range from 200 to 500° C.

14. The process according to claim 13 , wherein the chemical vapour infiltration process is performed at a temperature in the range from 400 to 500° C.

15. The process according to claim 1 , further comprising a step of passivating the intermediate particles.

16. The process according to claim 1 , further comprising a step of passivating the intermediate particles to remove the reactive Si—H bonds.

17. The process according to claim 1 , wherein the step of comminuting the intermediate particles is performed in an inert gas or in an environment where the oxygen concentration is less than 10 vol % oxygen.

18. The process according to claim 1 , wherein the micropores and/or mesopores of the porous carbon frameworks have a total pore volume as measured by gas adsorption of P 1 cm 3 /g, wherein the value of P 1 is in the range from 0.4 to 2.5.

19. The process according to claim 18 , wherein the value of P 1 is in the range from 0.65 to 1.2.

20. The process according to claim 1 , wherein the porous carbon frameworks have D 50 particle diameter of at least 30 μm.

21. The process according to claim 1 , wherein the porous carbon frameworks have a D 50 particle diameter of no more than 1000 μm.

22. The process according to claim 1 , wherein the porous carbon frameworks have a D 10 particle diameter of at least 5 μm and a D 90 particle diameter of no more than 1,500 μm.

23. The process according to claim 1 , wherein the porous carbon frameworks have a BET surface area of at least 750 μm 2 /g and no more than 4,000 μm 2 /g.

24. The process according to claim 1 , wherein the porous carbon frameworks have a PD 50 pore diameter as measured by gas adsorption of no more than 5 nm.

25. The process according to claim 1 , wherein the porous carbon frameworks have a PD 50 pore diameter as measured by gas adsorption of no more than 2 nm.

26. The process according to claim 1 , wherein the porous carbon frameworks have a PD 90 pore diameter as measured by gas adsorption of no more than 10 nm.

27. The process according to claim 1 , wherein the porous carbon frameworks have a volume fraction of micropores as measured by gas adsorption of greater than 0.5.

28. The process according to claim 1 , wherein the composite particles have a D 50 particle diameter in the range from 0.5 to 20 μm.

29. The process according to claim 1 , wherein the composite particles have a D 50 particle diameter in the range from 0.5 to 8 μm.

30. The process according to claim 4 , wherein the composite particles have a D 10 particle diameter of at least 0.2 μm and a D 90 particle diameter of no more than 80 μm.

31. The process according to claim 1 , wherein the composite particles have a particle size distribution span of no more than 5.

32. The process according to claim 1 , wherein the electroactive material is silicon, wherein the pore volume of the composite particles is expressed as P 1 cm 3 /g, and wherein the weight ratio, for the composite particles, of silicon to the porous carbon framework in the composite particles is in the range from [0.5×P 1 to 2.2×P 1 ]:1.

33. The process according to claim 1 , wherein the electroactive material is silicon, and wherein the composite particles comprise 30 to 80 wt % silicon.

34. The process according to claim 1 , wherein the composite particles comprise no more than 10 wt % oxygen.

35. A particulate material comprising the coated composite particles obtainable by the process according to claim 1 .

Assignees

• Nexeon Ltd

Inventors

• Yilmaz Sefa
• Mason Charles A
• Taylor Richard Gregory
• Bent David

Classifications

• B82Y30/00

  Nanotechnology for materials or surface science, e.g. nanocomposites · CPC title

• B82Y40/00

  Manufacture or treatment of nanostructures · CPC title

• H01M10/0525

  Rocking-chair batteries, i.e. batteries with lithium insertion or intercalation in both electrodes; Lithium-ion batteries · CPC title

• H01M4/628

  Inhibitors, e.g. gassing inhibitors, corrosion inhibitors · CPC title

• H01M4/625

  Carbon or graphite · CPC title