Silicon and carbon negative electrode material for lithium ion battery and preparation method thereof

A technology for lithium-ion batteries and negative electrode materials, applied in battery electrodes, nanotechnology for materials and surface science, secondary batteries, etc., can solve problems that affect applications, poor conductivity, and environmental protection, and achieve no decline in conductivity , stable structure and high efficiency

Inactive Publication Date: 2019-04-23
CHENGDU GUIBAO SCI & TECH
View PDF5 Cites 45 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

This method only coats a layer of pyrolytic carbon on the surface of silicon nanoparticles, which has poor conductivity, which affects its application in t...

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 and carbon negative electrode material for lithium ion battery and preparation method thereof
  • Silicon and carbon negative electrode material for lithium ion battery and preparation method thereof
  • Silicon and carbon negative electrode material for lithium ion battery and preparation method thereof

Examples

Experimental program
Comparison scheme
Effect test

Embodiment 1

[0061] Sand-mill 3um coarse silicon in a 1:1 mixed solution of acetone and ethanol to a median particle size of 50nm, and control the solid content to 10% to prepare a nano-silicon slurry. Add the mixed dispersant of isobutanol and glyceryl monostearate with a mass ratio of 1:1 to the nano-silicon slurry at a mass ratio of dispersant: nano-silicon slurry of 3:100, and stir for 1 hour using a high-speed disperser at 1300RPM Added to the vacuum kneader. Then according to the mass ratio of nano-silicon: artificial graphite is 5:100; select carbon nanotubes with a median particle size of 80nm according to carbon nanotubes: nano-silicon / graphite mass ratio is 1:100; : The mass ratio of nano-silicon / graphite is 5:100; weigh the corresponding materials and add them to the vacuum kneader, heat to 250°C under vacuum (vacuum degree ≤ 0.085Mpa), mix and knead for 4 hours, cool to room temperature, and dry in a blast drying oven Dry at 85°C for 4 hours to obtain the precursor.

[0062] ...

Embodiment 2

[0065] Silicon powder with a median particle size of 50nm is dispersed in a mixed solution of acetone and ethanol with a mass ratio of 1:1 by stirring and ultrasonic, and the solid content is controlled at 10%. Add the mixed dispersant of isobutanol and glyceryl monostearate with a mass ratio of 1:1 to the nano-silicon slurry according to the mass ratio of dispersant: nano-silicon slurry of 3:100, and use a high-speed disperser at 1300RPM to stir and disperse for 1h Then add to the vacuum kneader. Then according to the mass ratio of nano-silicon: artificial graphite is 5:100; select carbon nanotubes with a median particle size of 80nm according to carbon nanotubes: nano-silicon / graphite mass ratio is 1:100; : The mass ratio of nano-silicon / graphite is 5:100; weigh the corresponding materials and add them to the vacuum kneader, heat to 250°C under vacuum (vacuum degree ≤ 0.085Mpa), mix and knead for 4 hours, cool to room temperature, and dry in a blast drying oven Dry at 85°C ...

Embodiment 3

[0068] Compared with Implementation 1, except that the mass ratio of nano-silicon:artificial graphite is 10:100, the silicon-carbon composite anode material is prepared under the same process conditions.

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
Median particle sizeaaaaaaaaaa
Median particle sizeaaaaaaaaaa
Compaction densityaaaaaaaaaa
Login to view more

Abstract

The invention discloses a silicon and carbon composite negative electrode material for a lithium ion battery. The material is a three-dimensional composite material of a core-shell structure, and sequentially comprises nanometer silicon/ graphite, a conductive network layer and an organic cracking carbon layer from inside to outside, wherein the nanometer silicon/ graphite uses the graphite as aninner core volume expansion buffer base body; the nanometer silicon particles are embedded in graphite particle gaps or are attached onto the surface of the graphite particles; the conductive networklayer is formed by nanometer conductive agents which penetrate and insert into silicon particle gaps, silicon particle and graphite particle gaps and graphite particle gaps and/or coat the surface ofthe nanometer silicon particles; the organic cracking carbon layer uniformly coat the surface of the silicon nanometer silicon/graphite. The invention also discloses a preparation method of the silicon and carbon negative electrode material. The dispersing agents are used for directly compounding the nanometer silicon slurry, the nanometer conducting agents and organic carbon source; the production process is simple; the operation is easy; the method is suitable for mass production. The material has excellent first time efficiency, circulation performance, rate capability and relatively low volume expansion effects.

Description

technical field [0001] The invention relates to a material for lithium ion batteries, in particular to a silicon carbon negative electrode material for lithium ion batteries and a preparation method thereof, belonging to the technical field of lithium ion batteries. Background technique [0002] Lithium-ion batteries have high energy density, long life, no pollution, and excellent storage performance, and are widely used in 3C products, electric vehicles, and energy storage power stations. At present, the anode material of commercial lithium-ion batteries is graphite-based materials. Many anode material manufacturers can achieve a capacity of >360mAh / g, approaching its theoretical limit of 372mAh / g, but it can no longer meet the market's demand for high energy density energy storage systems. Therefore, the development of anode materials with high specific capacity has become an urgent need for the lithium battery industry. [0003] Silicon, as an anode material for lithi...

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
IPC IPC(8): H01M4/36H01M4/38H01M4/62H01M10/0525B82Y30/00
CPCB82Y30/00H01M4/362H01M4/366H01M4/386H01M4/625H01M10/0525Y02E60/10
Inventor 贺金味罗才坤王力君吴旭翔黄强王有治
Owner CHENGDU GUIBAO SCI & TECH
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