Porous silicon composite cluster and carbon composite thereof, and electrode, lithium battery, and electronic device each including the same

Patent metadata

Field	Value
Publication number	US-2019207221-A1
Application number	US-201816230946-A
Country	US
Kind code	A1
Filing date	Dec 21, 2018
Priority date	Jan 3, 2018
Publication date	Jul 4, 2019
Grant date	—

Abstract

A porous silicon composite includes: a porous core including a porous silicon composite secondary particle; and a shell disposed on a surface of the porous core and surrounding the porous core, wherein the porous silicon composite secondary particle includes an aggregate of silicon composite primary particles, each including silicon, a silicon suboxide on a surface of the silicon, and a first graphene on a surface of the silicon suboxide, wherein the shell include a second graphene, and at least one of the first graphene and the second graphene includes at least one element selected from nitrogen, phosphorus, and sulfur.

First claim

What is claimed is:

1 . A silicon-containing composite comprising:
a porous core comprising a porous silicon composite secondary particle; and a shell on a surface of the porous core and surrounding the porous core, wherein the porous silicon composite secondary particle comprises an aggregate of silicon composite primary particles, each comprising
silicon,
a silicon suboxide on a surface of the silicon, and
a first graphene on a surface of the silicon suboxide,
wherein the shell comprises a second graphene, and wherein at least one of the first graphene and the second graphene comprises at least one element selected from nitrogen, phosphorus, and sulfur.

2 . The silicon-containing composite of claim 1 , wherein the silicon suboxide is present in a form of a film, a matrix, or a combination thereof, and
the first graphene and the second graphene are each independently in a form of a film, a particle, a matrix, or a combination thereof,

3 . The silicon-containing composite of claim 1 , wherein the first graphene is disposed directly on the surface of the silicon suboxide, and the second graphene is disposed directly on the surface of the silicon-containing composite secondary particle.

4 . The porous silicon composite-containing of claim 1 , wherein an amount of the at least one element selected from nitrogen, phosphorus, and sulfur in the silicon-containing composite is about 0.2 atomic percent or less at a surface depth of 10 nanometers or less, as analyzed by X-ray photoelectron spectroscopy.

5 . The silicon-containing composite of claim 1 , wherein a carbon to silicon atomic ratio in the silicon-containing composite is from about 100:1 to about 200:1, when analyzed by X-ray photoelectron spectroscopy, and
wherein the carbon to silicon atomic ratio is increased as compared with the carbon to silicon atomic ratio in a silicon-containing composite which does not comprise the at least one element selected from nitrogen, phosphorous, and sulfur.

6 . The silicon-containing composite of claim 1 , wherein an intensity ratio of peak D to peak G in the silicon-containing composite is about 0.8 to about 1.5, when analyzed by Raman spectroscopy.

7 . The silicon-containing composite of claim 1 , wherein as measured by thermogravimetric analysis, a 20% weight loss temperature of the silicon-containing composite is about 7° C. to about 15° C. greater than a 20% weight loss temperature of a silicon-containing composite which does not comprise the at least one element selected from nitrogen, phosphorous, and sulfur.

8 . The silicon-containing composite of claim 1 , wherein the first graphene comprises a plurality of layers and the number of graphene layers in the first graphene of the core is identical to or different from the number of graphene layers in the second graphene of the shell, and the second graphene of the shell has a density which is greater than a density of the first graphene of the core.

9 . The silicon-containing composite of claim 1 , wherein the silicon-containing composite comprises a first core/shell structure and a second core/shell structure.

10 . The silicon-containing composite of claim 8 , wherein the first core/shell structure comprises the porous core comprising the porous silicon composite secondary particle and the shell comprising the second graphene on the surface of the porous core, and
the second core/shell structure comprises a core comprising the silicon and the silicon suboxide on a surface of the silicon, and the shell comprises the first graphene on a surface of the silicon suboxide.

11 . The silicon-containing composite of claim 1 , wherein the total amount of the first graphene and the second graphene is from about 0.1 parts by weight to about 2,000 parts by weight based on 100 parts by weight of silicon.

12 . The silicon-containing composite of claim 1 , wherein the first graphene of the silicon composite primary particle is spaced apart from a surface of the silicon suboxide a distance of about 10 nanometers or less, and
the first graphene is oriented at an angle of about 0° to about 90° with respect to a major axis of the silicon.

13 . The silicon-containing composite of claim 1 , wherein the first graphene comprises about 1 to about 30 graphene layers, and has a total thickness of about 0.3 nanometers to about 1,000 nanometers.

14 . The silicon-containing composite of claim 1 , wherein the second graphene of the shell is spaced apart from the silicon suboxide by a distance of about 1,000 nanometers or less, and
the second graphene is oriented at an angle of about 0° to about 90° with respect to a major axis of the silicon.

15 . The silicon-containing composite of claim 1 , where the second graphene comprises about 1 to about 30 graphene layers, and has a total thickness of about 0.6 nanometers to about 50 nanometers.

16 . The silicon-containing composite of claim 1 , wherein the silicon suboxide has a thickness of about 30 micrometers or less.

17 . The silicon-containing composite of claim 1 , wherein the silicon has a form comprising a sphere, a nanowire, a needle, a rod, a particle, a nanotube, a nanorod, a wafer, a nanoribbon, or a combination comprising at least one of the foregoing.

18 . The silicon-containing composite of claim 1 , wherein the porous silicon composite secondary particle has an average particle diameter of about 1 micrometer to about 30 micrometers, a specific surface area of about 0.1 square meter per gram to about 100 square meters per gram, and a density of about 0.1 gram per cubic centimeter to about 2.57 grams per cubic centimeter.

19 . The silicon-containing composite of claim 1 , wherein the silicon has an average particle diameter of about 10 nanometers to about 30 micrometers.

20 . The silicon-containing composite of claim 1 , wherein an amount of oxygen in the porous silicon composite is from about 0.01 atomic percent to about 15 atomic percent based on the total atomic percentage of oxygen, carbon, and silicon atoms in the silicon-containing composite cluster.

21 . The silicon-containing composite of claim 1 , further comprising a carbonaceous coating layer on a surface of the silicon-containing composite cluster, the carbonaceous coating layer comprising an amorphous carbon.

22 . The silicon-containing composite of claim 20 , wherein the carbonaceous coating layer further comprises at least one element selected from nitrogen, phosphorous, and sulfur.

23 . The silicon-containing composite of claim 20 , wherein the carbonaceous coating layer further comprises a crystalline carbon.

24 . The silicon-containing composite of claim 1 , wherein the carbonaceous coating layer is a non-porous continuous coating layer, and has a thickness of about 1 nanometer to about 5,000 nanometers.

25 . A method of preparing the silicon-containing composite of claim 1 , the method comprising:
providing a porous silicon secondary particle; supplying at least one of a nitrogen precursor, a phosphorus precursor, or a sulfur precursor, and a gas comprising a carbon source, to the porous silicon secondary particle; and thermally treating the porous silicon secondary particle composite to prepare the silicon-containing composite of claim 1 .

26 . The method of claim 25 , further comprising reacting the porous silicon secondary particle with the carbon source and the at least one of the nitrogen

Assignees

• Samsung Electronics Co Ltd
• Samsung Sdi Co Ltd

Inventors

• Son Inhyuk
• Kim Mijong
• Lee Jumyeung
• Lim Minwoo
• Choi Junghyun
• Han Sungsoo

Classifications

• H01M10/0565

  Polymeric materials, e.g. gel-type or solid-type · CPC title

• H01M4/1395

  of electrodes based on metals, Si or alloys · CPC title

• H01M4/364

  as mixtures · CPC title

• H01M4/366

  as layered products · CPC title

• H01M4/0471

  involving thermal treatment, e.g. firing, sintering, backing particulate active material, thermal decomposition, pyrolysis · CPC title