A silicon carbon composite negative electrode material and negative electrode sheet, its preparation method and lithium ion battery

A silicon-carbon composite material and negative electrode material technology, which is applied in the direction of battery, negative electrode, electrode manufacturing, etc., can solve the problems of volume expansion, electrochemical performance and cycle life to be improved, and poor cycle performance of lithium-ion batteries

Active Publication Date: 2022-07-01
厦门高容纳米新材料科技有限公司
View PDF2 Cites 0 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

However, due to the severe volume expansion (volume expansion of about 400%) of silicon materials during charge and discharge, the cycle performance of lithium-ion batteries is very poor.
In order to alleviate the volume expansion of silicon materials, silicon-carbon composite materials have been developed, and carbon is used to coat and modify silicon-based materials. However, the electrochemical performance and cycle life of existing silicon-carbon composite materials still need to be improved.

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
  • A silicon carbon composite negative electrode material and negative electrode sheet, its preparation method and lithium ion battery
  • A silicon carbon composite negative electrode material and negative electrode sheet, its preparation method and lithium ion battery

Examples

Experimental program
Comparison scheme
Effect test

preparation example Construction

[0034] The present invention also provides a method for preparing a negative electrode sheet. The method includes uniformly mixing a negative electrode material with a conductive agent, a binder and a solvent to obtain electrode slurry, coating the electrode slurry on the surface of the current collector, and drying it. Dry, wherein, the negative electrode material is the above-mentioned silicon carbon composite negative electrode material.

[0035] The main improvement of the preparation method of the negative electrode sheet provided by the present invention is that a new negative electrode material is adopted, and the specific types of the conductive agent, the binder and the solvent, as well as the amount of them and the negative electrode material, etc. can be compared with the existing ones. The technology is the same. For example, specific examples of the conductive agent include, but are not limited to, at least one of super carbon black, graphene, carbon fiber, and gr...

Embodiment 1

[0042] S1. Mix 100mL of ethanol and 20mL of water and heat to 60°C, add 2.5mL of ammonia water (concentration is 5wt%, the same below) and 0.5mL of ethylenediamine and mix well, then add 1g of 3-aminophenol, 2mL of formaldehyde and 4mL of silicic acid Ethyl ester was vigorously stirred at 30 rpm for 6 hours to form a precipitated product. The precipitated product was centrifuged, and the obtained solid product was dried at 60 °C for 3 h to obtain a silica / phenolic composite with a fractal structure.

[0043] S2. Take 2g of the above-mentioned silica / phenolic compound and 2g of magnesium powder, grind and mix them evenly and put them into a tube furnace. The tube furnace is protected by argon gas containing 1% hydrogen, and the tube furnace is heated to 350° C. The heat preservation reaction was performed for 10 hours, and the composite material powder of silicon and amorphous carbon with fractal structure was obtained by the reaction. The composite powder is taken out, treated...

Embodiment 2

[0046] S1. Mix 90 mL of ethanol and 10 mL of water and heat to 80°C, add 2 mL of ammonia water and 0.3 mL of ethylenediamine and mix well, then add 1.5 g of 3-aminophenol, 3.2 mL of formaldehyde and 6 mL of ethyl silicate, and stir vigorously at 150 rpm After 4 hours, a precipitated product was formed by the reaction, and the precipitated product was centrifuged, and the obtained solid product was dried at 90° C. for 1 h to obtain a silica / phenolic complex with a fractal structure.

[0047] S2: Take 2g of the above-mentioned silica / phenolic compound and put it into a tube furnace, pass argon gas containing 1% hydrogen into the tube furnace for protection, and heat the tube furnace to 1000° C. for calcination for 0.5h. The calcined product was cooled to room temperature, crushed, ground and mixed with 3 g of aluminum powder, and then put into the tube furnace again. hours, the reaction obtains a composite powder of silicon and amorphous carbon with a fractal structure. The com...

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
current efficiencyaaaaaaaaaa
current efficiencyaaaaaaaaaa
Login to view more

Abstract

The invention belongs to the field of new energy materials, and relates to a silicon-carbon composite negative electrode material and a negative electrode sheet, a preparation method thereof, and a lithium ion battery. The preparation method of the silicon-carbon composite negative electrode material includes: S1, dispersing phenol and / or aminophenol, formaldehyde and silicon precursor material in an alcohol-amine mixed aqueous solution, vigorously stirring the reaction at 20-90 ° C for at least 20 minutes, solid-liquid Separating and drying to obtain a silica / phenolic composite with a fractal structure; S2, calcining the silica / phenolic composite in the presence of magnesium powder and / or aluminum powder to obtain a silicon-carbon composite material with a fractal structure. When the silicon-carbon composite material is used as a negative electrode material for lithium-ion batteries, it can well overcome the failure caused by the volume change during charging and discharging, maintain a good conductive network, reduce volume expansion, improve the first reversible capacity and the first Coulomb efficiency, reduce the First cycle capacity loss and improved cycle stability.

Description

technical field [0001] The invention belongs to the field of new energy materials, and particularly relates to a silicon-carbon composite negative electrode material and a negative electrode sheet, a preparation method thereof, and a lithium ion battery. Background technique [0002] At present, with the development of new energy industry and the aggravation of environmental pollution, the development of electric vehicles is becoming more and more rapid, and lithium-ion batteries with high capacity, high power and long cycle life have also become urgently important. Lithium-ion batteries are the core of new energy vehicles and energy storage technology at this stage, and the electrochemical performance of lithium-ion batteries mainly depends on the positive and negative electrodes of the battery. Therefore, the development of positive and negative electrode materials with high energy density is the development of the next generation of high performance. The key to lithium-io...

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 Patents(China)
IPC IPC(8): H01M4/36H01M4/38H01M4/583H01M4/1395H01M4/1393H01M4/134H01M4/133H01M4/04H01M10/0525
CPCH01M4/364H01M4/386H01M4/583H01M4/1395H01M4/1393H01M4/134H01M4/133H01M4/0471H01M10/0525H01M2220/20H01M2004/027Y02E60/10
Inventor 蒋玉雄
Owner 厦门高容纳米新材料科技有限公司
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