Electroactive materials for metal-ion batteries

Patent metadata

Field	Value
Publication number	US-10424786-B1
Application number	US-201916274187-A
Country	US
Kind code	B1
Filing date	Feb 12, 2019
Priority date	Dec 19, 2018
Publication date	Sep 24, 2019
Grant date	Sep 24, 2019

Abstract

The invention relates to a particulate material comprising a plurality of composite particles, wherein the composite particles comprise: (a) a porous carbon framework comprising micropores and mesopores having a total pore volume of at least 0.6 cm3/g and no more than 2 cm3/g, where the volume fraction of micropores is in the range from 0.5 to 0.9 and the volume fraction of pores having a pore diameter no more than 10 nm is at least 0.75, and the porous carbon framework has a D50 particle size of less than 20 μm; (b) silicon located within the micropores and/or mesopores of the porous carbon framework in a defined amount relative to the volume of the micropores and/or mesopores.

First claim

The invention claimed is:

1. A particulate material comprising a plurality of composite particles, wherein the composite particles comprise:
(a) a porous carbon framework comprising micropores and mesopores, wherein
(i) the micropores and mesopores have a total pore volume as measured by gas adsorption of P 1 cm 3 /g, wherein P 1 has a value of at least 0.6 and no more than 2,
(ii) the volume fraction of micropores (φ a ) is in the range from 0.5 to 0.9, based on the total volume of micropores and mesopores;
(iii) the volume fraction of pores having a pore diameter no more than 10 nm (φ 10 ) is at least 0.75, based on the total volume of micropores and mesopores, and
(iv) the porous carbon framework has a D 50 particle size of less than 20 μm;

(b) a plurality of nanoscale elemental silicon domains located within the micropores and/or mesopores of the porous carbon framework;

wherein the weight ratio of silicon to the porous carbon framework in the composite particles is in the range from [1×P 1 to 1.9×P 1 ]:1.

2. A particulate material according to claim 1 , wherein P 1 has a value of at least 0.65.

3. A particulate material according to claim 1 , wherein P 1 has a value of no more than 1.8.

4. A particulate material according to claim 1 , wherein the volume fraction of micropores (φ a ) is in the range from 0.5 to 0.85.

5. A particulate material according to claim 1 , wherein the weight ratio of silicon to the porous carbon framework in the composite particles is at least the value given by [φ b +0.75]×P 1 , wherein φ b represents the volume fraction of mesopores, based on the total volume of micropores and mesopores.

6. A particulate material according to claim 1 , wherein the weight ratio of silicon to the porous carbon framework in the composite particles is at least the value given by [φ b +1]×P 1 .

7. A particulate material according to claim 1 , wherein the weight ratio of silicon to the porous carbon framework in the composite particles is at least the value given by [φ b +1.1]×P 1 .

8. A particulate material according to claim 1 , wherein the weight ratio of silicon to the porous carbon framework in the composite particles is no more than the value given by [φ b +1.6]×P 1 .

9. A particulate material according to claim 1 , wherein the weight ratio of silicon to the porous carbon framework in the composite particles is no more than the value given by [φ b +1.5]×P 1 .

10. A particulate material according to claim 1 , wherein the weight ratio of silicon to the porous carbon framework in the composite particles is at least 1.1×P 1 .

11. A particulate material according to claim 1 , wherein the volume fraction of pores having a pore diameter of no more than 10 nm (φ 10 ) is at least 0.75, based on the total volume of micropores and mesopores.

12. A particulate material according to claim 1 , wherein the volume fraction of pores having a pore diameter of no more than 5 nm (φ 5 ) is at least 0.7, based on the total volume of micropores and mesopores.

13. A particulate material according to claim 1 , wherein the porous carbon framework has a monomodal pore size distribution.

14. A particulate material according to claim 1 , wherein the porous carbon framework has a bimodal or multimodal pore size distribution.

15. A particulate material according to claim 1 , wherein the porous carbon framework comprises macropores having a diameter in the range from greater than 50 nm to 100 nm having a total volume P 2 cm 3 /g as measured by mercury porosimetry, wherein P 2 is no more than 0.2×P 1 .

16. A particulate material according to claim 1 , wherein the composite particles have a D 50 particle diameter of at least 0.5 μm.

17. A particulate material according to claim 1 , wherein the composite particles have a D 50 particle diameter of no more than 18 μm.

18. A particulate material according to claim 1 , wherein the composite particles have a D 10 particle diameter of at least 0.2 μm.

19. A particulate material according to claim 1 , wherein the composite particles have a D 90 particle diameter of no more than 40 μm.

20. A particulate material according to claim 1 , wherein the composite particles have a BET surface area of at least 0.1 m 2 /g and no more than 30 m 2 /g.

21. A particulate material according to claim 1 , wherein
P 1 has a value of at least 0.65 and no more than 1.8;
the volume fraction of micropores (φ a ) is in the range from 0.55 to 0.8; and
the weight ratio of silicon to the porous carbon framework in the composite particles is no more than the value given by [φ b +1.6]×P 1 .

22. A particulate material according to claim 21 , wherein the weight ratio of silicon to the porous carbon framework in the composite particles is at least the value given by [φ b +0.75]×P 1 , wherein φ b represents the volume fraction of mesopores, based on the total volume of micropores and mesopores.

23. A particulate material according to claim 1 , having specific capacity on lithiation of 1200 to 2340 mAh/g.

24. A composition comprising a particulate material as defined in claim 1 , and at least one other component selected from: (i) a binder; (ii) a conductive additive; and (iii) an additional particulate electroactive material.

25. A composition according to claim 24 , comprising from 1 to 20 wt % of the particulate material, based on the total dry weight of the composition.

26. A composition according to claim 24 , comprising from 10 to 98 wt % of the at least one additional particulate electroactive material, based on the total dry weight of the composition.

27. A composition according to claim 24 , wherein the at least one additional particulate electroactive material has a specific capacity on lithiation in the range from 100 to 600 mAh/g.

28. An electrode comprising a particulate material as defined in claim 1 electrical contact with a current collector.

29. A rechargeable metal-ion battery comprising:
(i) an anode, wherein the anode comprises an electrode as described in claim 28 ;
(ii) a cathode comprising a cathode active material capable of releasing and reabsorbing metal ions; and
(iii) an electrolyte between the anode and the cathode.

Assignees

• Nexeon Ltd

Inventors

• Mason Charles
• Taylor Richard
• Friend Christopher Michael

Classifications

• H01M2004/021

  Physical characteristics, e.g. porosity, surface area · CPC title

• H01M10/0525 Primary

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

• H01M4/625

  Carbon or graphite · CPC title

• H01M4/366 Primary

  as layered products · CPC title

• H01M4/364 Primary

  as mixtures · CPC title