Composite anode active material, method of preparing the same, and anode and lithium secondary battery including the composite anode active material

Patent metadata

Field	Value
Publication number	US-10199638-B2
Application number	US-201514982790-A
Country	US
Kind code	B2
Filing date	Dec 29, 2015
Priority date	Dec 31, 2014
Publication date	Feb 5, 2019
Grant date	Feb 5, 2019

Abstract

A composite anode active material including: a silicon material and a coating layer formed on at least a portion of a surface of the silicon material, wherein the coating layer is chemically bonded to the silicon material, and wherein the coating layer includes a hydrosilylation product of a C4-C30 alkene having a terminal —C(═O)OR group, wherein R is a hydrogen, a C1-C5 alkyl group, a C2-C6 heteroalkyl group, a C6-C12 aryl group, or a C7-C13 arylalkyl group, each of which except hydrogen is substituted or unsubstituted.

First claim

What is claimed is:

1. A composite anode active material comprising:
a silicon material; and
a coating layer formed on at least a portion of a surface of the silicon material,
wherein the coating layer is chemically bonded to the silicon material,
wherein the coating layer comprises a hydrosilylation product of a C4-C30 alkene comprising a terminal —C(═O)OR group, wherein R is a hydrogen, a C1-C5 alkyl group, a C2-C6 heteroalkyl group, a C6-C12 aryl group, or a C7-C13 arylalkyl group, each of which except hydrogen is substituted or unsubstituted, and
wherein the coating layer further comprises a polymer that has been chemically reacted with the —C(═O)OR group of the hydrosilylation product.

2. The composite anode active material of claim 1 , wherein the polymer before reacting comprises a hydroxyl group (—OH) capable of reacting with the —C(═O)OR group of the hydrosilylation product.

3. The composite anode active material of claim 1 , wherein the hydrosilylation product of the C4-C30 alkene is a hydrosilylation product of a hydride-terminated silicon material and the C4-C30 alkene.

4. The composite anode active material of claim 1 , wherein the C4-C30 alkene comprising the terminal —C(═O)OR group is a compound represented by Formula 1:

wherein, in Formula 1,
n is an integer of 1 to 10, and
R 1 , R 2 , and R are each independently a hydrogen, a C1-C5 alkyl group a C2-C6 heteroalkyl group, a C6-C12 aryl group, or a C7-C13 arylalkyl group, each of which is substituted or unsubstituted.

5. The composite anode active material of claim 4 , wherein the compound represented by Formula 1 is a compound represented by Formula 2:

wherein, in Formula 2,
n is an integer of 1 to 10, and
R is a hydrogen, a methyl group, or an ethyl group.

6. The composite anode active material of claim 4 , wherein the compound represented by Formula 1 is one of compounds represented by Formulae 3 to 5, 10-undecenoic acid, methyl 10-undecenoate, ethyl 10-undecenoate, 4-pentenoic acid, methyl 4-pentenate, ethyl 4-pentenate, 2-Methyl-4-pentenoic acid, 3-Methyl-4-pentenoic acid, 2,2-dimethyl-4-pentenoic acid, 8-nonenoic acid, methyl 8-nonenoate, and ethyl 8-nonenoate:

7. The composite anode active material of claim 1 , wherein the polymer is at least one selected from a polyvinylalcohol, a polyvinylacetate, and a cellulose ether.

8. The composite anode active material of claim 1 , wherein the silicon material is at least one selected from silicon (Si), SiO x (wherein 0<x<2), and a silicon alloy.

9. The composite anode active material of claim 1 , wherein an amount of the C4-C30 alkene comprising the terminal —C(═O)OR group is in a range of about 0.01 part to about 50 parts by weight based on 100 parts by weight of the silicon material.

10. The composite anode active material of claim wherein an amount of the polymer is in a range of about 0.01 part to about 50 parts by weight of the silicon material.

11. The composite anode active material of claim 1 , wherein the coating layer comprises a unit represented by Formula 6:

wherein, in Formula 6,
n is an integer of 1 to 10, and
R is a hydrogen, a methyl group, or an ethyl group, and
* refers to a binding site to a surface of the silicon material.

12. The composite anode active material of claim 1 , wherein the coating layer comprises a unit represented by Formula 7:

wherein, in Formula 7,
n is an integer of 1 to 10,
m is an integer of 5 to 18,000, and
* is a binding site to a surface of the silicon material.

13. The composite anode active material of claim 1 further comprising a carbon material.

14. A method of preparing the composite anode active material of claim 1 , the method comprising:
obtaining a hydride-terminated silicon material by etching the silicon material;
reacting the hydride-terminated silicon material with a C4-C30 alkene comprising a terminal —C(═O)OR group to obtain a hydrosilylation product comprising a terminal —C(═O)OR group, wherein R is a hydrogen, a C1-C5 alkyl group, a C2-C6 heteroalkyl group, a C6-C12 aryl group, or a C7-C13 arylalkyl group, each of which except hydrogen is substituted or unsubstituted to obtain the composite anode active material, and
reacting a polymer comprising a functional group capable of reacting with the terminal —C(═O)OR group of the hydrosilylation product to obtain the composite anode active material.

15. The method of claim 14 , further comprising
mixing the silicon material and a carbon material to obtain a mixture; and
milling the mixture before the obtaining of the hydride-terminated silicon material.

16. An anode comprising a composite anode active material, wherein the composite anode active material comprises:
a silicon material; and
a coating layer formed on at least a portion of a surface of the silicon material,
wherein the coating layer is chemically bonded to the silicon material,
wherein the coating layer comprises a hydrosilylation product of a C4-C30 alkene comprising a terminal —C(═O)OR group, wherein R is a hydrogen, a C1-C5 alkyl group, a C2-C6 heteroalkyl group, a C6-C12 aryl group, or a C7-C13 arylalkyl group, each of which except hydrogen is substituted or unsubstituted, and
wherein the coating layer further comprises a polymer that has been chemically reacted with the —C(═O)OR group of the hydrosilylation product.

17. A lithium secondary battery comprising the anode of claim 16 .

Assignees

• Samsung Electronics Co Ltd
• Samsung Sdi Co Ltd

Inventors

• Yang Jeeeun

Classifications

• H01M10/052

  Li-accumulators · CPC title

• H01M4/0402

  Methods of deposition of the material · CPC title

• Y02T10/7011

  Cross-Sectional Technologies · mapped topic

• H01M4/366 Primary

  as layered products · CPC title

• H01M4/134 Primary

  Electrodes based on metals, Si or alloys · CPC title