Lithium-ion battery negative electrode material, lithium-ion battery, method for manufacturing lithium-ion battery negative electrode material and apparatus for manufacturing the same

Abstract

The present invention provides a lithium-ion battery negative electrode material with good charge-discharge cycle characteristics, a lithium-ion battery, a method for manufacturing the lithium-ion battery negative electrode material, and an apparatus for manufacturing the same. [Solution] The negative electrode material of the lithium-ion battery includes aggregates or collections of thin silicon fine particles, each having a major axis of approximately 100 nm or less, which are stacked in a multilayered petal-like or scale-like manner, and graphene, graphene sheets, and / or amorphous carbon derived from graphite cover at least a portion of the aggregates or collections.

Claims

1. Silicon fine particles having a volume distribution of mode diameter and median diameter of 30 nm or less, and / or aggregates or aggregates of said silicon fine particles, comprising at least the said aggregates or aggregates in a state of being folded in a multilayered petal-like or scale-like manner, and The graphite surrounds at least a portion of the silicon fine particles and / or the aggregates or aggregates. Anode material for lithium-ion batteries.

2. At least a portion of the surface of the silicon fine particles and / or the aggregates or aggregates is covered with carbon. The negative electrode material for a lithium-ion battery according to claim 1.

3. The silicon fine particles and / or aggregates or aggregates having a volume distribution of mode diameter and median diameter of 20 nm or less A negative electrode material for a lithium-ion battery according to claim 1 or claim 2.

4. X-ray diffraction measurements of the silicon fine particles and / or the aggregates or assemblies show that the intensity of the diffraction peak attributed to Si(111) around 2θ = 28.4° is greater than the intensity of the other diffraction peaks. A negative electrode material for a lithium-ion battery according to any one of claims 1 to 3.

5. The aforementioned graphite is expanded graphite. A negative electrode material for a lithium-ion battery according to any one of claims 1 to 4.

6. It contains crystalline silicon chips or cutting debris, and The graphite surrounds at least a portion of the chips or cutting debris. Anode material for lithium-ion batteries.

7. At least a portion of the surface of the chips or cutting debris is covered with carbon. The negative electrode material for a lithium-ion battery according to claim 6.

8. A lithium-ion battery comprising the negative electrode material according to any one of claims 1 to 7, Lithium-ion battery.

9. An apparatus comprising the lithium-ion battery described in claim 8.

10. A grinding unit that grinds crystalline silicon to form silicon fine particles and / or aggregates or aggregates of said silicon fine particles having a volume distribution of mode diameter and median diameter of 30 nm or less, wherein the aggregates or aggregates are at least in a multilayered petal-like or scale-like folded state, A composite forming section comprises graphite surrounding at least a portion of the silicon fine particles and / or the aggregates or aggregates, thereby forming a composite containing the graphite and the silicon fine particles, or the graphite and the aggregates or aggregates. A manufacturing device for the negative electrode material of lithium-ion batteries.

11. The system further comprises a coating-forming portion that forms carbon covering at least a portion of the surface of the silicon fine particles and / or the aggregates or aggregates, The apparatus for manufacturing a negative electrode material for a lithium-ion battery according to claim 10.

12. The crystalline silicon is chips or cutting debris generated by a fixed abrasive wire. An apparatus for manufacturing a negative electrode material for a lithium-ion battery according to claim 10 or claim 11.

13. The grinding section comprises a ball mill and a bead mill used after the ball mill. An apparatus for manufacturing a negative electrode material for a lithium-ion battery according to any one of claims 10 to 12.

14. The composite forming section comprises a part in which graphite surrounds at least a portion of the crystalline silicon chips or cutting debris, thereby forming a composite containing the graphite and the chips or cutting debris. A manufacturing device for the negative electrode material of lithium-ion batteries.

15. The composite forming unit includes a bead mill machine. The apparatus for manufacturing a negative electrode material for a lithium-ion battery according to claim 14.

16. The system further comprises a coating forming portion that forms carbon covering at least a portion of the surface of the chips or cutting debris. An apparatus for manufacturing a negative electrode material for a lithium-ion battery according to claim 14 or claim 15.

17. A grinding step of grinding crystalline silicon to form silicon fine particles and / or aggregates or aggregates of said silicon fine particles having a volume distribution of mode diameter and median diameter of 30 nm or less, wherein the aggregates or aggregates are at least in a multilayered petal-like or scale-like folded state, The process includes a composite formation step in which graphite surrounds at least a portion of the silicon fine particles and / or the aggregates or aggregates, thereby forming a composite comprising the graphite and the silicon fine particles, or the graphite and the aggregates or aggregates. A method for manufacturing the negative electrode material of a lithium-ion battery.

18. The process further includes a coating formation step of forming carbon that covers at least a portion of the surface of the silicon fine particles and / or the aggregates or aggregates, A method for manufacturing a negative electrode material for a lithium-ion battery according to claim 17.

19. The crystalline silicon is chips or cutting debris generated by a fixed abrasive wire. A method for manufacturing a negative electrode material for a lithium-ion battery according to claim 17 or claim 18.

20. In the grinding step, the crystalline silicon is ground by a ball mill and then by a bead mill to form the aggregates or aggregates. A method for manufacturing a negative electrode material for a lithium-ion battery according to any one of claims 17 to 19.

21. The process includes a composite formation step, in which graphite surrounds at least a portion of crystalline silicon chips or cutting debris to form a composite comprising the graphite and the chips or cutting debris. A method for manufacturing the negative electrode material of a lithium-ion battery.

22. In the composite formation step, the composite is formed by a bead mill machine. A method for manufacturing a negative electrode material for a lithium-ion battery according to claim 21.

23. The process further includes a coating formation step of forming carbon that covers at least a portion of the surface of the chips or cutting debris, A method for manufacturing a negative electrode material for a lithium-ion battery according to claim 21 or claim 22.

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