Looking for breakthrough ideas for innovation challenges? Try Patsnap Eureka!

Silicon fine particles and method for producing same

A manufacturing method and technology of silicon particles, applied in chemical instruments and methods, silicon, silicon compounds, etc., can solve the problems of less damage/deformation, oxidation resistance, difficult continuous production, clogging of reaction tubes, etc., and achieve less irreversible reactions. Destructive, long-term stable performance effects

Inactive Publication Date: 2020-12-18
TOKUYAMA CORP
View PDF4 Cites 0 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

However, the method of Patent Document 1 has the following disadvantages: when the reaction temperature is near the upper limit of the above range, the reaction tube is clogged due to the precipitation of silicon, so that continuous production is difficult, and when the temperature is lowered, a large amount of chlorine remains. Silicon, easily reacts with moisture in the air and oxidizes
[0013] As mentioned above, the current situation is that it is not always possible to obtain silicon that has less damage / distortion due to expansion and contraction during lithium alloying, has a low oxygen concentration, and is also excellent in oxidation resistance.

Method used

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
View more

Image

Smart Image Click on the blue labels to locate them in the text.
Viewing Examples
Smart Image
  • Silicon fine particles and method for producing same
  • Silicon fine particles and method for producing same

Examples

Experimental program
Comparison scheme
Effect test

Embodiment 1

[0110] Synthesis of chlorine-containing silicon particle precursors

[0111] A graphite reaction cylinder with an inner diameter of 80 mm and a length of 2500 mm was heated to 750° C., and a silicon microparticle precursor was synthesized by feeding trichlorosilane at a rate of 900 g / min and entraining nitrogen at a rate of 37 NL (L is liter) / min. Baghouses separate / trap unreacted gases. The reaction rate of trichlorosilane was about 40%, and the baghouse captured about 70% of the resulting silicon particle precursors. The collected silicon fine particle precursor was stored in a storage container whose atmosphere was replaced with nitrogen.

[0112] When a part of the captured silicon microparticle precursor is released to the atmosphere, it reacts with moisture in the air to generate white smoke of hydrogen chloride and oxidizes it. Analysis of the silicon fine particle precursor after the atmosphere was released revealed that the oxygen concentration was 15.2%. The speci...

Embodiment 2

[0117] In Example 1, the silicon fine particle precursor was obtained under the same conditions except that the temperature of the reaction cylinder when synthesizing the silicon fine particle precursor was set at 850°C.

[0118] The obtained silicon fine particle precursor was dechlorinated under the same dechlorination conditions as in Example 1. As a result, the oxygen concentration (C o ) is 0.6% by mass, the chlorine concentration is 4.7% by mass, and the specific surface area (S) is 20m 2 / g. The ratio of oxygen concentration to specific surface area (C o / S) becomes 0.030. In addition, the average particle diameter was 129 nm, and the crystallite diameter was 8 nm.

Embodiment 3

[0120] In Example 1, the silicon fine particle precursor was obtained under the same conditions except that the temperature of the reaction cylinder during the synthesis of the silicon fine particle precursor was set at 700°C. The obtained silicon fine particle precursor was dechlorinated under the same dechlorination conditions as in Examples. As a result, the oxygen concentration (C o ) is 0.8% by mass, the chlorine concentration is 4.8% by mass, and the specific surface area (S) is 22m 2 / g. The ratio of oxygen concentration to specific surface area (C o / S) becomes 0.036. In addition, the average particle diameter was 117 nm, and the crystallite diameter was 7 nm.

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to View More

PUM

PropertyMeasurementUnit
diameteraaaaaaaaaa
diameteraaaaaaaaaa
specific surface areaaaaaaaaaaa
Login to View More

Abstract

Provided are silicon fine particles in which oxidization is effectively prevented and which have a crystallite diameter that is close to an amorphous solid. The silicon fine particles are characterized by having: an average primary particle diameter of 30-900 nm; a crystallite diameter of less than 10 nm; a chlorine concentration of 1-10 mass%; a ratio of oxygen concentration (Co: mass%) and a specific surface area (S: m2 / g), i.e., (Co / S), of less than 0.05. In this method for producing silicon fine particles, a gas including trichlorosilane is heated to 600-950 DEG C in a reaction chamber to thermally decompose the trichlorosilane and to generate a chlorine-containing silicon fine particle precursor. Next, the silicon fine particle precursor is collected, and then the collected siliconfine particle precursor is heated at 750-900 DEG C, while an inert gas is supplied or under a reduced pressure, and subjected to dechlorination.

Description

technical field [0001] The present invention relates to novel silicon microparticles and a method for producing the same. Specifically, silicon microparticles containing a trace amount of chlorine and having an oxygen content controlled within a predetermined range and having a specific primary particle diameter and crystallite diameter, and a method for producing the microparticles are provided. Background technique [0002] At present, silicon is used in various applications including an electrode material (negative electrode material) of a lithium ion secondary battery, or its application is proposed. [0003] In the past, carbon-based materials such as graphite and graphite were usually used as negative electrode materials for lithium-ion batteries, but the theoretical capacity was low at 372mAh / g (lithiated to LiC 6 case), expect higher capacity anode materials. Compared with carbon materials, silicon has a large storage capacity per unit mass of lithium, and its theo...

Claims

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to View More

Application Information

Patent Timeline
no application Login to View More
Patent Type & Authority Applications(China)
IPC IPC(8): C01B33/03H01M4/38
CPCC01B33/03Y02E60/10H01M4/386C01B33/02C01P2004/60H01M4/38C01P2002/60C01P2004/64C01P2006/80C01B33/037C01P2004/03C01P2004/62H01M10/0525H01M2004/021H01M2004/027
Inventor 望月直人石田晴之有行正男福原浩二
Owner TOKUYAMA CORP
Who we serve
  • R&D Engineer
  • R&D Manager
  • IP Professional
Why Patsnap Eureka
  • Industry Leading Data Capabilities
  • Powerful AI technology
  • Patent DNA Extraction
Social media
Patsnap Eureka Blog
Learn More
PatSnap group products

Browse by: Latest US Patents, China's latest patents, Technical Efficacy Thesaurus, Application Domain, Technology Topic, Popular Technical Reports.

© 2024 PatSnap. All rights reserved.Legal|Privacy policy|Modern Slavery Act Transparency Statement|Sitemap|About US| Contact US: help@patsnap.com