Silicon-carbon composite material and preparation method thereof

A technology of silicon-carbon composite materials and pastes, applied in nanotechnology for materials and surface science, electrical components, battery electrodes, etc., can solve problems affecting battery cycle stability, carbon layer separation, peeling, electrode pulverization, etc. problem, to achieve the effect of good battery cycle performance

Active Publication Date: 2012-10-03
DONGHUA UNIV
View PDF2 Cites 17 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

However, there are also major problems with silicon as the negative electrode material of lithium-ion batteries: during the charging and discharging process of the battery, the negative electrode material has a serious volume expansion effect (silicon is as high as 300%), which will cause electrode powdering, thereby reducing the service life of the battery; Repeated charging and discharging will cause agglomeration of negative electrode materials, which will affect the cycle stability of the battery
However, the thickness of the carbon coating layer of the composite material prepared by this method is uneven, and the bonding force between the carbon layer and the silicon alloy is weak. During the rapid charge and discharge process, the carbon layer is easy to separate and peel off from the silicon alloy, which seriously affects the cycle of the battery. stable 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
  • Silicon-carbon composite material and preparation method thereof

Examples

Experimental program
Comparison scheme
Effect test

Embodiment 1

[0038] (1) Beat the bacterial cellulose with a beater to prepare a uniform bacterial cellulose slurry;

[0039] (2) Take part of the bacterial cellulose slurry, add a certain amount of nano-scale silicon to the bacterial cellulose slurry, and add a certain amount of surfactant Triton-100, and mix evenly to obtain silicon-containing Bacterial cellulose slurry; wherein, the addition of silicon is 10wt.% of bacterial cellulose, and the addition of surfactant is 20wt.% of silicon;

[0040] (3) Pour the bacterial cellulose slurry and the silicon-containing bacterial cellulose slurry into a Buchner funnel for suction filtration and stack them alternately to obtain a silicon-containing bacterial cellulose film; the number of superimposed layers is 5 layers, the uppermost layer and the lowermost layer are all layers of the bacterial cellulose slurry, the thickness of the bacterial cellulose slurry is 0.1mm, and the thickness of the silicon-containing bacterial cellulose slurry layer i...

Embodiment 2

[0045] (1) Beat the bacterial cellulose with a beater to prepare a uniform bacterial cellulose slurry;

[0046] (2) Take part of the bacterial cellulose slurry, add a certain amount of nano-scale silicon to the bacterial cellulose slurry, and add a certain amount of surfactant Triton-100, and mix evenly to obtain silicon-containing Bacterial cellulose slurry; wherein, the addition of silicon is 100wt.% of bacterial cellulose, and the addition of surfactant is 100wt.% of silicon;

[0047] (3) Pour the bacterial cellulose slurry and the silicon-containing bacterial cellulose slurry into a Buchner funnel for suction filtration and stack them alternately to obtain a silicon-containing bacterial cellulose film; the number of superimposed layers is 11 layers, the uppermost layer and the lowermost layer are all layers of the bacterial cellulose slurry, the thickness of the bacterial cellulose slurry is 1mm, and the thickness of the silicon-containing bacterial cellulose slurry layer ...

Embodiment 3

[0052] (1) Beat the bacterial cellulose with a beater to prepare a uniform bacterial cellulose slurry;

[0053] (2) Take part of the bacterial cellulose slurry, add a certain amount of nano-scale silicon to the bacterial cellulose slurry, and add a certain amount of surfactant Triton-100, and mix evenly to obtain silicon-containing Bacterial cellulose slurry; wherein, the addition of silicon is 50wt.% of bacterial cellulose, and the addition of surfactant is 40wt.% of silicon;

[0054] (3) Pour the bacterial cellulose slurry and the silicon-containing bacterial cellulose slurry into a Buchner funnel for suction filtration and stack them alternately to obtain a silicon-containing bacterial cellulose film; the number of superimposed layers is 7 layers, the uppermost layer and the lowermost layer are all layers of the bacterial cellulose slurry, the thickness of the bacterial cellulose slurry is 0.5mm, and the thickness of the silicon-containing bacterial cellulose slurry layer i...

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
thicknessaaaaaaaaaa
Login to view more

Abstract

The invention relates to a silicon-carbon composite material and a preparation method thereof, and the silicon-carbon composite material is a mesh structure coated nano-grade silicon-carbon composite material. The mesh structure is a structure layer which is formed by mutually wound carbon fibers with a loose structure, and provided with uniform three-dimensional holes inside, and nano-grade silicon is uniformly dispersed in gaps of the mesh structure. The invention provides two preparation methods of the silicon-carbon composite materials, wherein the mesh structure is made by carbon pyrolysis and carbonization of bacterial cellulose. The silicon-carbon composite material is particularly suitable for cathode materials of lithium ion batteries, has high lithium storage capacity, and the special structure of the material can be used for effectively relieving the volume effect of silicon in a lithium ion battery charging and releasing process, so that the cycling stability of the anode material is further improved.

Description

technical field [0001] The invention relates to a silicon-carbon composite material and a preparation method thereof, in particular to a silicon-carbon composite material with nanoscale silicon coated in a network structure and a preparation method thereof. Background technique [0002] With the rapid development of the microelectronics industry and the automobile industry, and the popularization of various portable communication devices, personal computers, and small electronic devices, human requirements for lithium-ion batteries are also moving towards high energy density, high power density, high safety, Development in the direction of long life, fast charging and discharging, and light and thin. At present, commercial lithium-ion batteries use graphite as the negative electrode material. The theoretical specific capacity of graphite is only 372mAh / g, which has become a huge obstacle to improving the performance of lithium-ion batteries. At the same time, graphite has a...

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): H01M4/38H01M4/587B82Y30/00
CPCY02E60/12Y02E60/10
Inventor 王彪白雪君王华平
Owner DONGHUA 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

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