Preparation method of nano silicon-carbon negative electrode material

A technology of carbon anode material and nano-silicon, which is applied in the direction of nanotechnology, nanotechnology, nanotechnology for materials and surface science, etc., can solve the problems of complicated process and affecting the performance of final products, and achieve simple process, reduce attenuation, Avoid the effect of reunion

Pending Publication Date: 2022-04-26
SHANGHAI JIAO TONG UNIV
View PDF10 Cites 1 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

This reaction requires a two-step method to prepare Si / C materials, the process is more complicated, and the magnesium added in the formula is excessive, according to the requirements of the patent SiO 2 The reaction ratio with magnesium is 1:2.5, and it is difficult for magnesium powder to react with SiO 2 Uniform reaction occurs, and a large amount of magnesium will react with Si to form magnesium silicide, which will affect the performance of the final product

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
  • Preparation method of nano silicon-carbon negative electrode material
  • Preparation method of nano silicon-carbon negative electrode material
  • Preparation method of nano silicon-carbon negative electrode material

Examples

Experimental program
Comparison scheme
Effect test

Embodiment 1

[0044] Mix tetraethyl orthosilicate with ammonia water at a mass ratio of 8:2, and react at a constant temperature of 28°C to prepare nano-SiO 2 , prepared containing nano-SiO 2 Microsphere solution, after washing, take 1g nano-SiO 2 Disperse the solution in 170ml of deionized water, ultrasonically disperse for 10min, add 10.5mg of styrene monomer, and 0.35mg of methacrylic acid, mix thoroughly with electromagnetic stirring, heat in a water bath at 80°C, keep the temperature for 30min, then add 0.037mg of potassium persulfate, Stir at a constant speed under the protection of nitrogen, react at a constant temperature of 80° C. for 10 h, and then cool to room temperature to obtain polymer microspheres with nano-Si as the core. After washing with deionized water, it was vacuum filtered and dried in an oven at 50°C for 12 hours. After grinding, pass through a 400-mesh sieve to obtain coated nano-SiO 2 Particles to obtain the nano-silicon-carbon precursor Put the above-mentioned...

Embodiment 2

[0048] Mix tetraethyl orthosilicate with ammonia water at a ratio of 7:3, and react at a constant temperature of 28°C to prepare nano-SiO 2 , prepared containing nano-SiO 2 The solution of the microspheres, after washing, was taken containing 2g nano-SiO 2 solution, ultrasonically dispersed for 10 minutes, added 10.5 mg of styrene monomer, and 0.35 mg of methacrylic acid, mixed thoroughly with electromagnetic stirring, heated in a water bath at 80°C, and kept at a constant temperature for 30 minutes, added 0.040 mg of potassium persulfate, stirred at a constant speed under nitrogen protection, 80 ℃ constant temperature reaction for 10h, cooled to room temperature, and freeze-dried to obtain coated nano-SiO 2 For the microspheres, pass the microspheres through a 400-mesh sieve to obtain a nano-silicon-carbon precursor. The above-mentioned nano-silicon-carbon precursor and 1.6g of magnesium powder were put into crucibles respectively, then placed in an electric furnace, protec...

Embodiment 3

[0051] Mix tetraethyl orthosilicate and ammonia water at a ratio of 6:4, and react at a constant temperature of 28°C to prepare nano-SiO 2 , prepared containing nano-SiO 2 For the solution of microspheres, after washing, take a solution containing 4g of nano-SiO2, add 0.4g of glucose to obtain a uniformly dispersed mixed solution; dry the mixed solution at 105°C for 24h, remove water, and obtain dry nano-SiO2 coated with glucose. 2 particles. After crushing with a ball mill, pass through a 400-mesh sieve to obtain glucose-coated nano-SiO 2 microspheres to obtain nano-silicon carbon precursors. Put the SiO2 and 3.2g magnesium powder in the above granules into crucibles respectively, then place them in an electric furnace under argon protection, heat up to 850°C at a heating rate of 15°C / min, keep the temperature constant for 2 hours, take it out after cooling. That is, the nano-silicon-carbon negative electrode material is obtained.

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
sizeaaaaaaaaaa
Login to view more

Abstract

The invention relates to a preparation method of a nano silicon-carbon negative electrode material, which comprises the following steps: preparing nano SiO2 microspheres from tetraethoxysilane, and uniformly coating the surfaces of the nano SiO2 microspheres with a polymer or an organic matter layer to form a nano silicon-carbon precursor; under the protection of argon, the nanometer silicon carbon precursor and magnesium powder are pyrolyzed, a polymer on the surface of the nanometer silicon carbon precursor is carbonized to form a carbon shell coating the surface of SiO2, meanwhile, the magnesium powder is volatilized into magnesium steam, the magnesium steam permeates the carbon shell and enters the interior to react with nanometer SiO2, and the nanometer silicon carbon negative electrode material is prepared. Compared with the prior art, the prepared nano silicon-carbon negative electrode material is of a core-shell structure, silicon in the nano silicon-carbon negative electrode material is a core, the particle size of the nano silicon-carbon negative electrode material is all nanoscale, the size of the silicon is uniform, and the content of the silicon is 5wt%-60wt%; the surface of nano Si is coated with a carbon layer, and nano silicon is protected by the carbon layer, so that the capacity of the lithium ion battery is improved, and the cycle life of the lithium ion battery is prolonged.

Description

technical field [0001] The present invention relates to materials and preparation methods in the technical field of lithium batteries, in particular to a preparation method for a nano-silicon carbon negative electrode material with uniform particle size. 2 The specific preparation process for preparing nano-silicon-carbon anode materials. Background technique [0002] As an energy storage basis, lithium-ion batteries have many advantages, such as stable voltage, high energy density, long cycle life, etc., so they are widely used in telephones, speakers, portable medical equipment, electric motorcycles and electric vehicles, etc. "Made in China 2025" clarifies the development plan of power lithium batteries: by 2020, the energy density of batteries will reach 300Wh / kg; by 2025, the energy density of batteries will reach 400Wh / kg; so there is an urgent need to develop new negative electrode materials. This puts forward higher requirements for the negative electrode materials ...

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): H01M4/62H01M4/60H01M4/48H01M4/36B82Y40/00B82Y30/00
CPCH01M4/366H01M4/48H01M4/602H01M4/625B82Y30/00B82Y40/00
Inventor 胡晓斌林升炫肖佳佳
Owner SHANGHAI JIAO TONG UNIV
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