Porous core-shell structure silicon-carbon negative electrode material for lithium ion battery and preparation method thereof

A technology of lithium-ion batteries and negative electrode materials, applied in the direction of nanotechnology for materials and surface science, battery electrodes, negative electrodes, etc., can solve the problems of silicon electrode powdering and falling off, poor cycle performance, and current collector loss, etc., to achieve The effect of reducing absolute volume expansion, improving electrical conductivity, and increasing migration rate

Active Publication Date: 2020-05-12
MAANSHAN KEDA PURUI ENERGY TECH CO LTD +2
View PDF13 Cites 8 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

However, silicon has a volume expansion of up to 300% during charge and discharge, which will cause the silicon electrode to pulverize and fall off during the charge and discharge cycle, and lose electrical contact with the current collector, eventually leading to battery failure and showing extremely poor cycle 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
  • Porous core-shell structure silicon-carbon negative electrode material for lithium ion battery and preparation method thereof
  • Porous core-shell structure silicon-carbon negative electrode material for lithium ion battery and preparation method thereof
  • Porous core-shell structure silicon-carbon negative electrode material for lithium ion battery and preparation method thereof

Examples

Experimental program
Comparison scheme
Effect test

Embodiment 1

[0039] A method for preparing a porous core-shell structure silicon-carbon negative electrode material for a lithium ion battery, comprising the steps of:

[0040] (1) Preparation of nano-silicon slurry: 500 g of polycrystalline silicon powder with a median particle size of 10 μm and 5 g of polyvinylpyrrolidone, according to the mass ratio of silicon powder: polyvinylpyrrolidone = 100:1, are added to absolute ethanol, and the mixed solution solidifies The content is 10%, and the mixed slurry is introduced into a sand mill, and ground for 100 hours under the protection of nitrogen to obtain a nano-silicon slurry with a median particle size of 50nm, wherein the diameter of the ground zirconium ball is 0.1mm, and the zirconium ball and silicon powder The mass ratio of is 10:1;

[0041] (2) Preparation of porous carbon: put 900g of sucrose in a muffle furnace, feed nitrogen and oxygen mixed gas, in which the volume ratio of oxygen is 80%, heat up to 700°C, control the degree of co...

Embodiment 2

[0046] A method for preparing a porous core-shell structure silicon-carbon negative electrode material for a lithium ion battery, comprising the steps of:

[0047] (1) Preparation of nano-silicon slurry: the median particle size is 30 μm polycrystalline silicon powder 400g and sodium lauryl sulfate 2g, according to the mass ratio of silicon powder: sodium lauryl sulfate=100:0.5, join propanol , the solid content of the mixed solution is 20%, the mixed slurry is introduced into a sand mill, and ground for 80 hours under nitrogen protection to obtain a nano-silicon slurry with a median particle size of 100nm, wherein the diameter of the zirconium ball is 0.2mm, The mass ratio of zirconium balls to silicon powder is 10:1;

[0048] (2) Preparation of porous carbon: put 1000g of starch in a muffle furnace, feed nitrogen and oxygen mixed gas, in which the volume ratio of oxygen is 70%, heat up to 800°C, control the degree of combustion of starch, and obtain a porosity of 65 % porou...

Embodiment 3

[0053] A method for preparing a porous core-shell structure silicon-carbon negative electrode material for a lithium ion battery, comprising the steps of:

[0054] (1) Preparation of nano-silicon slurry: the median particle size is 50 μm polycrystalline silicon powder 300g and Gur gum 15g, according to the mass ratio of silicon powder: Gur gum=100:5, join in acetone, the solid content of the mixed solution is 30%, the mixed slurry is introduced into a star-type ball mill, and ground for 50 hours under the protection of nitrogen to obtain a nano-silicon slurry with a median particle size of 100nm, wherein the diameter of the ground zirconium ball is 0.3mm, and the mass of the zirconium ball and silicon powder The ratio is 10:1;

[0055] (2) Preparation of porous carbon: put 675g of glucose in a muffle furnace, feed nitrogen and oxygen mixed gas, in which the volume ratio of oxygen is 50%, heat up to 900°C, control the degree of combustion of glucose, and obtain a porosity of 60...

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
thicknessaaaaaaaaaa
particle sizeaaaaaaaaaa
Login to view more

Abstract

The invention belongs to the field of lithium ion battery negative electrode materials and electrochemistry, and particularly relates to a porous core-shell structure silicon-carbon negative electrodematerial for a lithium ion battery and a preparation method thereof. The silicon-carbon negative electrode material is of a porous core-shell structure, wherein the inner core is formed by homogeneously compounding nano silicon and porous carbon, and the shell is coated with carbon formed by an organic cracking carbon source. According to the porous core-shell structure silicon-carbon negative electrode material prepared by the invention, the porous carbon is formed by combustion and carbonization of a carbon precursor, the nano-silicon is embedded into pores of the porous carbon, and the prepared negative electrode material is high in specific capacity, good in cycle performance and high-rate performance charge-discharge performance, simple in preparation process, low in cost and suitable for industrialization.

Description

technical field [0001] The invention belongs to the field of lithium-ion battery negative electrode materials and electrochemistry, and in particular relates to a silicon-carbon negative electrode material with a porous core-shell structure for lithium-ion batteries and a preparation method thereof. Background technique [0002] The conventional negative electrode material on the market is graphite negative electrode, which has good cycle performance and safety performance, and has been widely used in the production and application of lithium-ion batteries. However, the theoretical specific capacity of graphite negative electrode is only 372mAh / g, which cannot meet the requirements of high specific capacity. Capacity lithium battery demand. Silicon has an ultra-high theoretical specific capacity (4200mAh / g) and a low delithiation potential (<0.5V), and the voltage platform of silicon is slightly higher than that of graphite. It is difficult to cause lithium precipitation ...

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): H01M4/36H01M4/38H01M4/62H01M10/0525B82Y30/00
CPCH01M4/366H01M4/386H01M4/625H01M4/628H01M10/0525B82Y30/00H01M2004/021H01M2004/027Y02E60/10
Inventor 胡亮张少波俞有康张志权
Owner MAANSHAN KEDA PURUI ENERGY TECH 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