Si-C-N composite negative pole material and preparation method thereof

A negative electrode material and silicon-based material technology, applied in battery electrodes, electrical components, circuits, etc., can solve the problems of negative electrode material cycle stability and poor rate performance, achieve excellent rate performance, buffer volume effect, and improve conductivity Effect

Active Publication Date: 2015-02-25
CHERY AUTOMOBILE CO LTD
View PDF6 Cites 2 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

[0006] The negative electrode materials provided by the prior art have poor cycle stability and rate performance

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
  • Si-C-N composite negative pole material and preparation method thereof
  • Si-C-N composite negative pole material and preparation method thereof
  • Si-C-N composite negative pole material and preparation method thereof

Examples

Experimental program
Comparison scheme
Effect test

preparation example Construction

[0028] In the first aspect, an embodiment of the present invention provides a method for preparing a silicon-carbon-nitrogen composite negative electrode material, including:

[0029] Step 101. Under an argon atmosphere, heat the mixture of silicon source and nitrogen source to 600-1000°C at a heating rate of 0.5-10°C / min, and sinter at 600-1000°C for 3-15 hours, and then Cool down to room temperature to obtain a nitrogen-doped silicon-based material.

[0030] In the embodiment of the present invention, a mixture of a silicon source and a nitrogen source is sintered in an argon atmosphere, so that nitrogen is doped into the silicon material to form a nitrogen-doped silicon-based material. Since the silicon material is doped with nitrogen, the energy band width of the silicon material can be reduced, the conductivity of the silicon material can be effectively improved, and the cycle stability and rate performance of the prepared negative electrode material can be improved.

[...

Embodiment 1

[0046] Preparation of nitrogen-doped silicon-based materials:

[0047] Mix silicon monoxide and ethylenediamine evenly, then heat the mixture of silicon monoxide and ethylenediamine to 800°C at a heating rate of 3°C / min under an argon atmosphere, and sinter at this temperature for 7 hours. Then cool down to room temperature to obtain a nitrogen-doped silicon-based material. Wherein, the mass fraction of nitrogen in the nitrogen-doped silicon-based material is 4%.

[0048] Coating artificial graphite on the surface of nitrogen-doped silicon-based materials:

[0049] According to the mass ratio: nitrogen-doped silicon-based material: artificial graphite = 2:11, mix the nitrogen-doped silicon-based material and artificial graphite evenly, and in a nitrogen atmosphere, heat the nitrogen-doped silicon-based material at a heating rate of 5°C / min. The mixture of material and artificial graphite was heated to 650°C and sintered at this temperature for 6 hours. Then the temperature ...

Embodiment 2

[0051] Preparation of nitrogen-doped silicon-based materials:

[0052] Mix tetraethyl orthosilicate and acetamide evenly, and then heat the mixture of silicon monoxide and ethylenediamine to 650°C at a heating rate of 1°C / min under an argon atmosphere, and sinter at this temperature for 5 hours. Then cool down to room temperature to obtain a nitrogen-doped silicon-based material. Wherein, the mass fraction of nitrogen in the nitrogen-doped silicon-based material is 0.5%.

[0053] Coating artificial graphite on the surface of nitrogen-doped silicon-based materials:

[0054] According to the mass ratio: nitrogen-doped silicon-based material: artificial graphite = 4:1, mix the nitrogen-doped silicon-based material and artificial graphite evenly, and in a nitrogen atmosphere, heat the nitrogen-doped silicon-based material at a heating rate of 5°C / min. The mixture of material and artificial graphite was heated to 700°C and sintered at this temperature for 8 hours. Then the tempe...

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
particle diameteraaaaaaaaaa
particle sizeaaaaaaaaaa
densityaaaaaaaaaa
Login to view more

Abstract

The invention discloses a Si-C-N composite negative pole material and a preparation method thereof and belongs to the field of lithium ion battery negative pole materials. The preparation method comprises the following steps of heating a mixture of a Si source and an N source to a temperature of 600-1000 DEG C at a heating rate of 0.5-10 DEG C/min in an Ar atmosphere, carrying out sintering at a temperature of 600-1000 DEG C for 3-15h, carrying out cooling to a room temperature to obtain an N-doped Si-based material, mixing the N-doped Si-based material and graphite to obtain a uniform mixture, heating the mixture of the N-doped Si-based material and graphite to a temperature of 500-900 DEG C at a heating rate of 0.5-10 DEG C/min in an N atmosphere, carrying out sintering at a temperature of 500-900 DEG C for 1-10h, and carrying out cooling to a room temperature to obtain the Si-C-N composite negative pole material. Through use of N in the Si material, Si material bandwidth is reduced and conductivity is improved. Through coating of the N-doped Si-based material with graphite, volume effects of the Si material is effectively buffered. The Si-C-N composite negative pole material has excellent multiplying power performances and cycle stability.

Description

technical field [0001] The invention relates to the field of negative electrode materials for lithium ion batteries, in particular to a silicon-carbon-nitrogen composite negative electrode material and a preparation method thereof. Background technique [0002] Lithium battery (that is, lithium ion battery) is a rechargeable battery that uses carbon active material as the negative electrode and a lithium-containing compound as the positive electrode. The charging and discharging process is the intercalation and deintercalation process of lithium ions: when charging, lithium ions are deintercalated from the positive electrode, pass through the electrolyte and separator, and embed in the negative electrode. The more lithium ions are embedded in the negative electrode, the higher the specific charge capacity of the battery On the contrary, during discharge, lithium ions are deintercalated from the negative electrode, pass through the electrolyte and separator, and intercalate i...

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): H01M4/36H01M4/62
CPCH01M4/364H01M4/62Y02E60/10
Inventor 刘三兵梅周盛
Owner CHERY AUTOMOBILE CO LTD
Who we serve
  • R&D Engineer
  • R&D Manager
  • IP Professional
Why Eureka
  • Industry Leading Data Capabilities
  • Powerful AI technology
  • Patent DNA Extraction
Social media
Try Eureka
PatSnap group products

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

© 2024 PatSnap. All rights reserved.Legal|Privacy policy|Modern Slavery Act Transparency Statement|Sitemap