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

A technology of silicon carbon composite material and negative electrode material, which is applied in battery electrodes, secondary batteries, circuits, 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, preparation method thereof, and lithium ion battery
  • A silicon carbon composite negative electrode material and negative electrode sheet, preparation method thereof, and lithium ion battery

Examples

Experimental program
Comparison scheme
Effect test

Embodiment approach

[0035] In the present invention, the carbon particulate material coated with a silica layer on the surface may be a graphite particulate material or other carbon particulate material coated with a silica layer on the surface, which can be obtained commercially, or can be obtained according to existing There are various methods to prepare. According to a specific embodiment of the present invention, the graphite particle material whose surface is coated with a silica layer is prepared according to the following method: 10 g of acid-treated graphite particles are dispersed in 80-120 mL of pH 8-13 In ammonia water, add 1-3 mL of silane coupling agent for functionalization treatment for 3-8 h, then add 80-120 mL of ethanol and dropwise add 20-40 mL of ethanol solution containing 1-5 wt% silicon precursor material III, the silicon precursor material Ⅲ is a compound that can be hydrolyzed into silica, the reaction is stirred at room temperature for 5-20 hours, the solid-liquid is se...

Embodiment 1

[0052] S1. Disperse 1 g of polystyrene balls in 100 mL of ammonia water with a pH value of 10, add 2 mL of silane coupling agent (MPS) for functionalization for 5 h, add 100 mL of ethanol, drop 30 mL of ethanol solution containing 6% TEOS, and stir at room temperature 10h, solid-liquid separation, the obtained solid product was dried at 60 °C, then heated to 600 °C and treated in an air atmosphere for 30 min to obtain hollow SiO 2 Microspheres.

[0053] The above hollow SiO 2 The microspheres were dispersed in 50mL ethanol-water mixed solution (the volume ratio of ethanol and water was 2.3:1, the same below), 1.5mL ammonia water (concentration was 5wt%, the same below) and 0.5mL ethylenediamine were added to mix well, and then added 0.5 g of 3-aminophenol, 2 mL of formaldehyde and 2 mL of ethyl silicate were vigorously stirred (150 rpm) for 5 h at 40 °C, centrifuged, and the obtained solid product was dried at 60 °C for 2 h to obtain a hollow surface with fractal structure. ...

Embodiment 2

[0057] S1. Disperse 10 g of acid-treated graphite particles in 100 mL of ammonia water with pH 8, add 2 mL of silane coupling agent (MPS) for functionalization for 5 h, add 100 mL of ethanol, and then dropwise add 30 mL of an ethanol solution containing 3wt% TEOS. Stir at room temperature for 10 h. Solid-liquid separation, and the obtained solid product is dried to obtain a graphite particle material (denoted as SiO) coated with a silica layer on the surface. 2 / C microspheres).

[0058] The above SiO 2 / C microspheres were dispersed in 50 mL of ethanol-water mixture, 2.5 mL of ammonia water and 0.5 mL of ethylenediamine were added to mix well, then 1 g of 3-aminophenol, 2 mL of formaldehyde and 4 mL of ethyl silicate were added, and vigorous stirring at 40°C (30 rpm ) reacted for 6 h, centrifuged, and the obtained solid product was dried at 60° C. for 3 h to obtain a silica / phenolic composite material with a fractal structure on the surface of the graphite core.

[0059] S...

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

No PUM 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 hollow silica microspheres or carbon particle materials coated with silica layers, phenol and / or aminophenol, formaldehyde and silicon precursor materials in In the mixed aqueous solution of alkanolamine, the reaction is vigorously stirred at 20 to 90 ° C for at least 20 minutes, the solid-liquid is separated, and dried to obtain a silica / phenolic composite material with a fractal structure on the surface; S2, the silica / phenolic composite material is placed in magnesium calcined in the presence of powder and / or aluminum powder. When the silicon-carbon composite material is used as a negative electrode material for a lithium-ion battery, 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, and reduce the first time Cycling capacity loss and improved cycling 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): H01M4/36H01M4/38H01M4/583H01M4/62H01M10/0525
CPCH01M4/362H01M4/583H01M4/625H01M4/386H01M10/0525Y02E60/10
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