NANOCOMPOSITE BATTERY ELECTRODE PARTICLES WITH CHANGING PROPERTIES

• US 20160104882A1
• Filed: 10/13/2015
• Published: 04/14/2016
• Est. Priority Date: 10/14/2014
• Status: Active Grant

• Current Assignee: Sila Nanotechnologies Inc.
• Original Assignee: Sila Nanotechnologies Inc.
• Inventors: YUSHIN, Gleb, BERDICHEVSKY, Eugene Michael, JACOBS, Alexander Thomas, ZDYRKO, Bogdan, NESE, Alper, HARRIS, Damian
• Granted Patent: US 10,340,520 B2
• Time in Patent Office: Days
• US Class Current: 1/1
• 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 4/0402 Methods of deposition of the material
• CPC Class Codes: H01M 4/13 Electrodes for accumulators with non-aqueous electrolyte, e.g. for lithium-accumulators; Processes of manufacture thereof
• CPC Class Codes: H01M 4/362 Composites
• CPC Class Codes: H01M 4/386 Silicon or alloys based on silicon
• CPC Class Codes: H01M 4/388 Halogens
• CPC Class Codes: H01M 4/625 Carbon or graphite
• CPC Class Codes: Y02E 60/10 Energy storage using batteries

Abstract

Battery electrode compositions and methods of fabrication are provided that utilize composite particles. Each of the composite particles may comprise, for example, a high-capacity active material and a porous, electrically-conductive scaffolding matrix material. The active material may store and release ions during battery operation, and may exhibit (i) a specific capacity of at least 220 mAh/g as a cathode active material or (ii) a specific capacity of at least 400 mAh/g as an anode active material. The active material may be disposed in the pores of the scaffolding matrix material. According to various designs, each composite particle may exhibit at least one material property that changes from the center to the perimeter of the scaffolding matrix material.

Claims

1. A battery electrode composition comprising composite particles, each composite particle comprising:

a high-capacity active material provided to store and release ions during battery operation, wherein the active material exhibits (i) a specific capacity of at least 220 mAh/g as a cathode active material or (ii) a specific capacity of at least 400 mAh/g as an anode active material; and

a porous, electrically-conductive scaffolding matrix material within the pores of which the active material is disposed,

wherein each composite particle exhibits at least one material property that changes from the center to the perimeter of the scaffolding matrix material.

2. The battery electrode composition of claim 1, wherein the active material is an anode active material and comprises silicon.

3. The battery electrode composition of claim 1, wherein the active material is a cathode active material and comprises fluorine.

4. The battery electrode composition of claim 1, wherein the scaffolding matrix material comprises carbon.

5. The battery electrode composition of claim 1, wherein the at least one material property comprises a material composition of the scaffolding matrix material that changes from the center to the perimeter of the scaffolding matrix material.

6. The battery electrode composition of claim 5, wherein each composite particle further comprises a shell at least partially encasing the active material and the scaffolding matrix material, the shell being substantially permeable to the ions stored and released by the active material and forming a barrier between the active material and an electrolyte solvent.

7. The battery electrode composition of claim 1, wherein the at least one material property comprises a mechanical property of the scaffolding matrix material that changes from the center to the perimeter of the scaffolding matrix material.

8. The battery electrode composition of claim 7, wherein the mechanical property includes a lower elastic modulus or lower hardness near the center of the scaffolding matrix material as compared to the perimeter of the scaffolding matrix material.

9. The battery electrode composition of claim 1, wherein the at least one material property comprises a degree of disorder of the scaffolding matrix material that changes from the center to the perimeter of the scaffolding matrix material.

10. The battery electrode composition of claim 1, wherein the at least one material property comprises an average pore size of the scaffolding matrix material that changes from the center to the perimeter of the scaffolding matrix material.

11. The battery electrode composition of claim 10, wherein the average pore size is larger near the center of the scaffolding matrix material as compared to the perimeter of the scaffolding matrix material.

12. The battery electrode composition of claim 10, wherein the average pore size is larger near the center of the scaffolding matrix material and the perimeter of the scaffolding matrix material as compared to an intermediate region of the scaffolding matrix located between the center and the perimeter.

13. The battery electrode composition of claims 10, wherein the average pore size in the center of the scaffolding matrix material particles is in the range of about 2 nm to about 100 nm.

14. The battery electrode composition of claim 1, wherein the at least one material property comprises a pore orientation of the scaffolding matrix material that changes from the center to the perimeter of the scaffolding matrix material.

15. The battery electrode composition of claim 1, wherein the at least one material property comprises a volume fraction of the active material to the scaffolding matrix material that changes from the center to the perimeter of the scaffolding matrix material.

16. The battery electrode composition of claim 1, wherein the at least one material property comprises a material composition of the active material that changes from the center to the perimeter of the scaffolding matrix material.

17. The battery electrode composition of claim 16, wherein the material composition includes a first active material that is more concentrated near the center of the scaffolding matrix material and a second active material that is more concentrated near the perimeter of the scaffolding matrix material, and wherein the first active material has a higher energy density than the second active material.

18. The battery electrode composition of claim 1, wherein the at least one material property comprises a density of the composite particle that changes from the center to the perimeter of the scaffolding matrix material.

19. The battery electrode composition of claim 18, wherein the density is higher near the center of the scaffolding matrix material as compared to the perimeter of the scaffolding matrix material.

20. The battery electrode composition of claim 1, wherein each composite particle further comprises a shell at least partially encasing the active material and the scaffolding matrix material, the shell being formed of a thermally-sensitive material that substantially reduces its electrical or ionic conductivity at temperatures above about 80°

C.

21. The battery electrode composition of claim 1, wherein each composite particle exhibits a surface roughness characterized by a peak-to-valley difference in the range of about 1 nm to about 500 nm.

22. The battery electrode composition of claim 1, wherein each composite particle further comprises a conductive carbon shell at least partially encasing the active material and the scaffolding matrix material.

23. A metal-ion battery, comprising:

ion-permeable anode and cathode electrodes, wherein at least one of the electrodes comprises the battery electrode composition of claim 1;

an electrolyte ionically coupling the anode and the cathode electrodes; and

a separator electrically separating the anode and the cathode electrodes.

24. A method of fabricating a battery electrode composition comprising composite particles, the method comprising:

providing a high-capacity active material to store and release ions during battery operation, wherein the active material exhibits (i) a specific capacity of at least 220 mAh/g as a cathode active material or (ii) a specific capacity of at least 400 mAh/g as an anode active material; and

forming a porous, electrically-conductive scaffolding matrix material within the pores of which the active material is disposed,

wherein each composite particle is formed with at least one material property that changes from the center to the perimeter of the scaffolding matrix material.

25. The method of claim 24, wherein the forming comprises introducing one or more functional groups within the scaffolding matrix material with a distribution that changes from the center to the perimeter of the scaffolding matrix material.

26. The method of claim 24, wherein the forming comprises infiltrating the active material into the scaffolding matrix material.