Porous silicon/carbon composite material synthesized in situ by taking porous polymer microspheres as template, preparation method and lithium ion battery

A porous polymer, in-situ synthesis technology, applied in battery electrodes, secondary batteries, active material electrodes, etc., can solve problems such as unfavorable industrial production, unfavorable long-term circulation, complex preparation procedures, and achieve a safe and controllable reduction process. , the effect of shortening the diffusion path and improving the cycle performance

Pending Publication Date: 2022-02-22
昱瓴新能源科技(浙江)有限公司
View PDF4 Cites 1 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

The metals used in this method are very active metals, and their single substance cost is high and dangerous, so it is not conducive to industrial production.
[0008] CN103531760 discloses a porous silicon / carbon composite microsphere with egg yolk-eggshell structure and a preparation method thereof. The core of the microsphere provided by it is a porous submicron silicon sphere with a diameter of 400-900 nm, and the shell is porous carbon with a thickness of 10-100 nm. 60nm, the inner diameter of the cavity is 800-1400nm, and its preparation method is based on SiO 2 Coating the core with carbon source, firing to obtain porous carbon-coated SiO 2 powder, and then through alkali treatment part of SiO 2 Porous carbon-coated SiO with egg yolk-eggshell structure 2 powder, and then SiO by magnestic reduction 2 It is reduced to silicon powder, and finally the excess silicon dioxide is treated by HF to obtain silicon / carbon composite microspheres of porous carbon coated with porous silicon of egg yolk-eggshell structure. The preparation process of this method is complicated, and the inner diameter of the cavity is difficult to control. A certain expansion space is reserved for silicon, but the silicon particles are not densely covered by porous carbon, and the conductivity is poor, which is not good for its long-term cycle

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
  • Porous silicon/carbon composite material synthesized in situ by taking porous polymer microspheres as template, preparation method and lithium ion battery
  • Porous silicon/carbon composite material synthesized in situ by taking porous polymer microspheres as template, preparation method and lithium ion battery
  • Porous silicon/carbon composite material synthesized in situ by taking porous polymer microspheres as template, preparation method and lithium ion battery

Examples

Experimental program
Comparison scheme
Effect test

Embodiment 1

[0044] see figure 1 , take 50g of porous polystyrene microspheres with a particle size D50 of 500nm and a pore size of about 20nm, add an appropriate amount of water, heat to 40°C, and stir at 200r / min for 20min to disperse evenly; then slowly add to the obtained suspension solution Add 50g of ethyl silicate, and continue to stir at 200r / min at 40°C for 20min; then filter the mixed solution, wash with deionized water, and dry at 50°C for 1h, then add 250g of aluminum powder with a particle size of 3μm As a reducing agent, milling and mixing yielded Intermediate A.

[0045] The temperature was raised to 800° C. at 2° C. / min, and kept for 1 h under vacuum atmosphere, and the intermediate product A was reduced to obtain the intermediate product B. Put the intermediate product B into 2.0mol / L hydrochloric acid for pickling for 0.5h, wash with deionized water, filter, and dry at 50°C for 1h to obtain a porous silicon / carbon composite material, see figure 2 .

[0046] The obtain...

Embodiment 2

[0048] Take 50g of porous polyvinyl chloride microspheres with a particle size D50 of 5μm and a pore size of about 70nm, add an appropriate amount of water, heat to 50°C, and stir at 500r / min for 30min to disperse evenly; then slowly add 600g of methyl silicate and 400g of sodium silicate, and continuously stirred at 50°C at 500r / min for 40min; then the mixed solution was filtered, washed with deionized water, and dried at 70°C for 2h, and then added 3000g of 5 μm aluminum powder was used as a reducing agent, and the intermediate product A was obtained by grinding and mixing.

[0049] The temperature was raised to 900°C at 5°C / min, and kept for 2h under an argon atmosphere, and the intermediate product A was reduced to obtain the intermediate product B. Put the intermediate product B into 3.0 mol / L sulfuric acid for pickling for 1 h, wash with deionized water, filter, and dry at 80° C. for 2 h to obtain a porous silicon / carbon composite material.

[0050] The obtained porous ...

Embodiment 3

[0052] Take 20g of porous polyethylene microspheres with a particle size D50 of 15μm and a pore size of about 90nm and 30g of porous polyurethane microspheres with a particle size of D50 of 15μm and a pore size of about 70nm. to disperse evenly; then slowly add 700g of methoxysilane and 800g of ethoxysilane to the resulting suspension solution, and continue stirring at 600r / min for 40min at 55°C; then the mixed solution is filtered, Wash with deionized water, dry at 80°C for 1.5 h, then add 650 g of aluminum powder with a particle size of 8 μm and 850 g of titanium hydride powder with a particle size of 10 μm as reducing agents, grind and mix to obtain intermediate product A.

[0053] The temperature was raised to 950°C at 10°C / min, and kept for 4h under a nitrogen atmosphere, and the intermediate product A was reduced to obtain the intermediate product B. The intermediate product B was put into 3.0 mol / L sulfuric acid for pickling for 2 hours, washed with deionized water, fil...

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 sizeaaaaaaaaaa
sizeaaaaaaaaaa
sizeaaaaaaaaaa
Login to view more

Abstract

The invention relates to a porous silicon/carbon composite negative electrode material in-situ synthesized by taking porous polymer microspheres as a template, a preparation method and a lithium ion battery. The preparation process comprises the following steps of: adding porous polymer microspheres into water, heating and stirring to obtain a suspension solution; adding a silicon source into the suspension solution to obtain a mixed solution; filtering the mixed solution, washing the mixed solution with deionized water and drying the mixed solution in sequence, then adding a reducing agent, and conducting grinding and mixing to obtain an intermediate product A; treating the intermediate product A through a thermal reduction process to obtain an intermediate product B; and carrying out acid pickling on the intermediate product B, washing with deionized water, filtering, and drying to obtain a final product. Compared with the prior art, a carbon layer obtained through in-situ compounding can better improve the electrical conductivity, the cycling stability, the charge-discharge efficiency, the rate capability and other electrochemical properties of a silicon negative electrode, and the unique micro-nano pores reserve a lithium-intercalation expansion space for silicon and reduces the absolute volume change of the composite material in the charge-discharge process.

Description

technical field [0001] The invention relates to the field of preparation of negative electrode materials for lithium ion batteries, in particular to a porous silicon / carbon composite material synthesized in situ using porous polymer microspheres as a template, a preparation method and a lithium ion battery. Background technique [0002] With the advancement of electronics industry, electric vehicles and aerospace technology, higher requirements are placed on the performance of lithium-ion batteries. Therefore, in order to achieve breakthroughs in energy density and power density of lithium-ion batteries, the crucial "bottleneck" issue is how to design and develop new electrode materials. In the research field of lithium-ion batteries, the research focus is on negative electrode materials. At present, the theoretical lithium storage capacity of the graphite electrode itself is relatively low (LiC 6 , 372mAh / g) makes it difficult to make breakthroughs. Therefore, it is extr...

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): H01M4/36H01M4/38H01M4/583H01M4/62H01M10/0525
CPCH01M4/362H01M4/386H01M4/583H01M4/625H01M10/0525H01M2004/027H01M2004/021Y02E60/10
Inventor 刘萍万文文王磊陈辉高瑞星徐怀良常凯铭
Owner 昱瓴新能源科技(浙江)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