High-capacity silicon carbon negative electrode material, and preparation method and applications thereof

A negative electrode material and high-capacity technology, applied in the field of high-capacity silicon-carbon negative electrode materials and their preparation, can solve the problems of consuming water resources and time, difficulty in realizing industrial production, high cost, etc., to reduce absolute volume expansion and relieve volume Swelling problem, effect of easy mass production

Inactive Publication Date: 2018-09-14
SHAANXI COAL & CHEM TECH INST
View PDF5 Cites 17 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

[0004] At present, most technical routes have problems such as complex process, high cost and difficulty in realizing industrial production.
Such as patent CN20130307450.0 reports a kind of preparation method of nano-silicon / graphene lithium-ion battery negative electrode material, wherein involves the preparation of graphene oxide colloidal solution, this process needs to carry out repeated centrifugal washing to graphene oxide suspension (until solution The pH value is neutral), the process yield is low, and consumes a lot of water resources and time, it is difficult to realize the large-scale preparation of high-capacity silicon-carbon materials; patent CN201510027926.4 uses chemical vapor deposition to prepare nano-silicon composite negative electrode materials, At present, the chemical vapor deposition method is still difficult to achieve uniform deposition of nano-silicon on graphite, and there are problems such as poor product uniformity and low output.

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
  • High-capacity silicon carbon negative electrode material, and preparation method and applications thereof
  • High-capacity silicon carbon negative electrode material, and preparation method and applications thereof
  • High-capacity silicon carbon negative electrode material, and preparation method and applications thereof

Examples

Experimental program
Comparison scheme
Effect test

preparation example Construction

[0039] A method for preparing a high-capacity silicon-carbon material of the present invention comprises the following steps:

[0040] S1. Ball milling: disperse the nano-silicon and carbon materials in the required metering ratio in a solvent for wet ball milling, the ball milling speed is 300-2000rpm, the ball milling time is 0.2-8.0h, preferably, the ball milling time is 0.5-2.5h;

[0041]The carbon material is any one of graphite, nanofiber, graphene, porous carbon or a combination thereof; the solvent is any one of deionized water, ethanol, N-methylpyrrolidone, acetone, ethylene glycol or a combination thereof.

[0042] S2. Ultrasonic: Dilute the ball-milled slurry to a solid content of 10-40% and perform ultrasonic treatment at 5°C. The ultrasonic power is 500-2000W, and the ultrasonic time is 0.5-2.0h;

[0043] S3. Slurry preparation: add carbon source and surfactant to the ultrasonicated slurry, stir vigorously for 0.5-5h, and rotate at 800-2000rpm;

[0044] Carbon so...

Embodiment 1

[0050] Synthesis of high-capacity silicon-carbon anode materials

[0051] (1) Ball milling: disperse silicon with a medium particle size of 230nm and graphite of 8um in ethanol at a mass ratio of 3.25:1 for ball milling, the ball-to-material ratio is 8:1, the rotating speed is 1000rpm, and the ball milling time is 2h;

[0052] (2) Ultrasonic: Adjust the solid content of the slurry after ball milling to 20%, and ultrasonicate for 30 minutes at 5°C, and the ultrasonic power is 1300W;

[0053] (3) Add surfactant and carbon source: add 0.03mol / L ethanol of PVP8000 and PEG20000 to the slurry and stir vigorously for 2.0h at a speed of 800rpm;

[0054] (4) Spray drying: the inlet and outlet temperatures are 150 and 60°C respectively, and the liquid inlet speed is 8mL / min;

[0055] (5) Heat treatment: N 2 Atmosphere, 480°C 2h+850°C 3h.

[0056] Characterization of physicochemical properties of silicon-carbon composites:

[0057] The microscopic morphology of the silicon carbon mat...

Embodiment 2

[0062] (1) Ball milling: disperse silicon with a particle size of 80nm, graphite A of 20um, and graphite B of 8um in ethanol at a mass ratio of 45:25:5 for ball milling, the ball-to-material ratio is 8:1, the ball milling speed is 400rpm, time 2h;

[0063] (2) Ultrasonic: Adjust the solid content of the slurry after ball milling to 15%, and ultrasonically perform 30 minutes at 5°C with an ultrasonic power of 1000W;

[0064] (3) Spray drying: the inlet and outlet temperatures were 150°C and 60°C respectively, and the feed rate was 5mL / min to prepare precursor C;

[0065] (4) Add carbon source: add coal tar pitch to the slurry, adjust the solid content to 10%, stir vigorously for 1.0h, and the rotating speed is 1500rpm;

[0066] (5) Spray drying: the inlet and outlet temperatures are 150 and 60°C respectively, and the liquid inlet speed is 7.5mL / min;

[0067] (6) Heat treatment: N2 atmosphere, 2h at 200°C + 3h at 850°C.

[0068] The test results of thermogravimetric method sh...

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
particle diameteraaaaaaaaaa
Login to view more

Abstract

The invention discloses a high-capacity silicon carbon negative electrode material, and a preparation method and applications thereof. According to the preparation method, ball milling, surfactant treatment, ultrasonic wave treatment, spray drying, and the like are adopted, and related technological parameters are optimized for effective dispersion and combination of nanometer silicon and a carbonmaterial to prepare the silicon carbon composite material with a high specific capacity ranging from 1000 to 1700mAh / g and long cycle life. The preparation method is simple; cost is low; industrialized production is convenient to realize; and the silicon carbon composite material high in specific capacity and long in cycle life is prepared through ball milling, surfactant treatment, ultrasonic wave treatment, spray drying, and the like, and based on optimized related technological parameters.

Description

technical field [0001] The invention belongs to the technical field of secondary batteries, and in particular relates to a high-capacity silicon-carbon negative electrode material and a preparation method and application thereof. Background technique [0002] In recent years, with the rapid development and wide application of various 3C electronic products and electric vehicles, people's requirements for battery energy density are increasing day by day, and the current battery material system has gradually been unable to meet the high energy density requirements. As far as negative electrode materials are concerned, the theoretical capacity of widely commercialized graphite-based negative electrode materials is only 372mAh / g, which has been unable to meet the development requirements of lithium-ion batteries with light weight, miniature size and long battery life. Silicon material has a theoretical specific capacity (4200mAh / g, Li 22 Si 5 ), wide sources and low cost have ...

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
CPCB82Y30/00H01M4/362H01M4/386H01M4/625H01M4/628H01M10/0525H01M2004/021H01M2004/027Y02E60/10
Inventor 杨时峰张大鹏田占元李广杰邵乐邓增社
Owner SHAANXI COAL & CHEM TECH INST
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