A method for compounding silicon-carbon-silicon dioxide in an extruder to prepare lithium battery negative electrode

A technology of silicon dioxide and nano-silicon dioxide, which is applied in battery electrodes, secondary batteries, negative electrodes, etc., can solve the problems of complex preparation process and difficulty in continuous production, and achieve volume effect, improve composite performance, and prepare The process is simple and controllable

Active Publication Date: 2021-10-12
梧州市同创新能源材料有限公司
View PDF7 Cites 0 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

[0007] Aiming at the volume effect defects of silicon-based negative electrode materials for lithium batteries during use, and at the same time solving the problem that the existing silicon oxide negative electrode materials are complicated in preparation process and difficult to produce continuously, the present invention proposes a silicon-carbon- A method for preparing the negative electrode of a lithium battery by compounding silicon dioxide, thereby using a simple process to obtain a carbon powder-coated silicon oxide negative electrode material

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 method for compounding silicon-carbon-silicon dioxide in an extruder to prepare lithium battery negative electrode
  • A method for compounding silicon-carbon-silicon dioxide in an extruder to prepare lithium battery negative electrode
  • A method for compounding silicon-carbon-silicon dioxide in an extruder to prepare lithium battery negative electrode

Examples

Experimental program
Comparison scheme
Effect test

Embodiment 1

[0036] (1) Mix nano-silicon powder and nano-silicon dioxide evenly according to the molar ratio of 1:1, then place 25kg of nano-silicon powder and silicon dioxide mixed powder in a vacuum furnace with a vacuum degree of 50 Pad, and then heat up to 1500 ℃ for heat treatment to obtain silicon oxide vapor;

[0037] (2) Introduce the silicon oxide vapor into the first mixing area of ​​the twin-screw extruder through the guide tube. The screw diameter is 40mm, the aspect ratio is 45, and the screw speed is 100rpm. At the same time, 105kg of graphite powder is passed through the feed port Once added to the first mixing area, the twin-screw extruder is evacuated to a vacuum of 750Pa through the vacuum port at the end of the first mixing area, and the first mixing area is cooled using circulating cooling water, and then 2kgCMC, 2kgSBR and 2kgCTAB are added to the second mixing area through the second feeding port, and 7.5kgPTFE and 4kg paraffin powder are added to the third mixing are...

Embodiment 2

[0039] (1) Mix nano-silicon powder and nano-silicon dioxide evenly according to the molar ratio of 1:0.9, then place 22kg of nano-silicon powder and silicon dioxide mixed powder in a vacuum furnace with a vacuum degree of 20 Pad, and then heat up to 1300 ℃ for heat treatment to obtain silicon oxide vapor;

[0040] (2) The silicon oxide vapor is introduced into the first mixing area of ​​the twin-screw extruder through the guide tube. The screw diameter is 30mm, the aspect ratio is 40, and the screw speed is 50rpm. At the same time, 108kg of graphite powder is passed through the feed port Once added to the first mixing area, vacuum the twin-screw extruder through the vacuum port at the end of the first mixing area to a vacuum of 600Pa, and use circulating cooling water to cool the first mixing area, and then put 1.5kgCMC , 1.5kgSBR, 1.5kgCTAB are added to the second mixing area through the second feed port, 6kgPTFE, 3.5kg paraffin powder are added to the third mixing area throu...

Embodiment 3

[0042] (1) Mix nano-silicon powder and nano-silicon dioxide evenly according to the molar ratio of 1:1.1, then place 28kg of nano-silicon powder and silicon dioxide mixed powder in a vacuum furnace with a vacuum degree of 80 Pad, and then heat up to 1700 ℃ for heat treatment to obtain silicon oxide vapor;

[0043] (2) The silicon oxide vapor is introduced into the first mixing area of ​​the twin-screw extruder through the guide tube. The screw diameter is 40mm, the aspect ratio is 50, and the screw speed is 180rpm. At the same time, 102kg of graphite powder is passed through the feed port Once added to the first mixing area, the twin-screw extruder is evacuated to a vacuum of 700Pa through the vacuum port at the end of the first mixing area, and the temperature of the first mixing area is lowered with circulating cooling water, and then 2.5kgCMC , 2.5kgSBR, 2.5kgCTAB are added to the second mixing area through the second feed port, 9kgPTFE and 4.5kg paraffin powder are added t...

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 proposes a method for compounding silicon-carbon-silicon dioxide in an extruder to prepare a negative electrode of a lithium battery. The negative electrode of a lithium battery is obtained by heat treatment of nano-silicon powder and nano-silicon dioxide to obtain silicon oxide vapor, and then uses diversion The pipe is introduced into the twin-screw extruder, and then the graphite powder, CMC, SBR, CTAB, PTFE, and paraffin powder are added to the twin-screw extruder for mixed extrusion, and then the extruded powder is passed through the screen at the outlet. made by screening. The method provided by the present invention obtains an effectively coated silicon oxide / carbon negative electrode material by mixing and extruding auxiliary agents such as silicon oxide vapor and graphite powder in a screw extruder, which can effectively prevent silicon-based negative electrode materials from being The volume effect in use, and the whole preparation process is simple and controllable, get rid of the problems of high equipment requirements and complicated preparation process in the original process, and have broad application prospects.

Description

technical field [0001] The invention relates to the technical field of lithium battery negative electrode materials, in particular to a method for compounding silicon-carbon-silicon dioxide in an extruder to prepare lithium battery negative electrodes. Background technique [0002] Lithium batteries are currently one of the most widely used secondary battery systems. It has higher energy density, higher working voltage, limited self-discharge and lower maintenance cost. The capacity of a lithium battery depends on the active lithium ions of the positive electrode material and the ability of the negative electrode material to intercalate and remove lithium. The stability of the positive and negative electrodes in various environments determines the performance of the battery and even seriously affects the safety of the battery. Therefore, the electrode The performance of the lithium battery determines the overall performance of the lithium battery to a certain extent. Among...

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 & AuthorityPatents(China)
IPC IPC(8): H01M4/1391H01M4/04H01M4/48H01M4/62H01M10/0525
CPCH01M4/0411H01M4/1391H01M4/483H01M4/625H01M4/628H01M10/0525H01M2004/021H01M2004/027Y02E60/10
Inventor陈庆廖健淞司文彬李钧
Owner梧州市同创新能源材料有限公司