Preparation and application of PEO-based film coated silicon carbon electrode

A technology of coating silicon and thin films, applied in the direction of negative electrodes, battery electrodes, active material electrodes, etc., can solve the problem of Si nano particle crushing, achieve the effect of reducing the falling off of crushed particles and good electrical contact

Inactive Publication Date: 2020-03-27
INST OF PROCESS ENG CHINESE ACAD OF SCI
View PDF3 Cites 3 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

However, without proper surface protection, bare Si nanoparticles (NPs) can still be pulverized by deintercalation and lithiation.

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
  • Preparation and application of PEO-based film coated silicon carbon electrode

Examples

Experimental program
Comparison scheme
Effect test

Embodiment 1

[0025] (1) Weigh silicon carbon negative electrode material silicon carbon 650, aqueous binder sodium hydroxymethyl cellulose (CMC), styrene-butadiene rubber (SBR), and conductive agent (superP), according to the mass ratio of 8:0.5:0.5; 1 Mix and grind evenly, add an appropriate amount of ultrapure water and place on a magnetic stirrer to fully stir for 8 hours. Coated, and then placed in a vacuum oven to dry at 80°C for later use.

[0026] (2) Dissolve PEO in acetonitrile solution, fully mix and dissolve, and then add lithium bistrifluoromethanesulfonimide to prepare a mixed solution with a mass fraction of PEO of 1%, wherein the molar ratio of PEO to lithium salt is 1:15 .

[0027] (3) Fix the dried silicon carbon electrode sheet on the glass plate, select a 500mm scraper, scrape and coat the PEO mixed solution on the electrode sheet, and dry it in the glove box to volatilize the acetonitrile solvent to obtain a PEO-based film coating Silicon carbon electrodes.

Embodiment 2

[0029] (1) Weigh silicon carbon negative electrode material silicon carbon 650, aqueous binder sodium hydroxymethyl cellulose (CMC), styrene-butadiene rubber (SBR), and conductive agent (superP), according to the mass ratio of 8:0.5:0.5; 1 Mix and grind evenly, add an appropriate amount of ultrapure water and place on a magnetic stirrer to fully stir for 8 hours. Coated, and then placed in a vacuum oven to dry at 80°C for later use.

[0030] (2) Dissolve PEO in acetonitrile solution, fully mix and dissolve, and then add lithium bistrifluoromethanesulfonimide to prepare a mixed solution with a mass fraction of PEO of 3%, wherein the molar ratio of PEO to lithium salt is 1:15 .

[0031] (3) Fix the dried silicon carbon electrode sheet on the glass plate, select a 500mm scraper, scrape and coat the PEO mixed solution on the electrode sheet, and dry it in the glove box to volatilize the acetonitrile solvent to obtain a PEO-based film coating Silicon carbon electrodes.

Embodiment 3

[0033] (1) Weigh silicon carbon negative electrode material silicon carbon 650, aqueous binder sodium hydroxymethyl cellulose (CMC), styrene-butadiene rubber (SBR), and conductive agent (superP), according to the mass ratio of 8:0.5:0.5; 1 Mix and grind evenly, add an appropriate amount of ultrapure water and place on a magnetic stirrer to fully stir for 8 hours. Coated, and then placed in a vacuum oven to dry at 80°C for later use.

[0034] (2) Dissolve PEO in acetonitrile solution, fully mix and dissolve, and then add lithium bistrifluoromethanesulfonimide to prepare a mixed solution with a mass fraction of PEO of 5%, wherein the molar ratio of PEO to lithium salt is 1:15 .

[0035] (3) Fix the dried silicon carbon electrode sheet on the glass plate, select a 500mm scraper, scrape and coat the PEO mixed solution on the electrode sheet, and dry it in the glove box to volatilize the acetonitrile solvent to obtain a PEO-based film coating Silicon carbon electrodes.

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
thicknessaaaaaaaaaa
Login to view more

Abstract

The invention provides a preparation method and application of a PEO-based thin film coated silicon carbon electrode. The method comprises the following steps: 1) preparing a silicon-carbon negative electrode plate as a substrate; 2) preparing a PEO-based mixed solution, and blade-coating the prepared solution on a silicon-carbon electrode substrate; and 3) airing the silicon-carbon electrode plate to obtain the silicon-carbon electrode coated with the PEO-based film, and applying the silicon-carbon electrode to the lithium ion battery. A mixed solution of PEO and a lithium salt is prepared byutilizing the elasticity of PEO and the property that the lithium salt can conduct lithium ions. Blade-coating the mixed solution on a silicon-carbon electrode plate to form a layer of protective film; and when the PEO mass concentration of the PEO-based mixed solution is 3%, the battery shows optimal cycling stability. In the charging and discharging process, the lithium salt in the film can conduct lithium ions, the elastic PEO film can buffer stress caused by volume expansion in the charging and discharging process, and breakage and smashing of the electrode plate are reduced.

Description

technical field [0001] The invention belongs to the field of lithium ion batteries, and in particular relates to the preparation and application of a PEO-based film-coated silicon-carbon electrode. Background technique [0002] In view of the current global warming and energy crisis, it is very important to find renewable energy and high-performance energy storage equipment. Rechargeable lithium-ion batteries (LIBs) have attracted considerable attention as energy storage devices due to their long life, high energy and power densities, chemical stability, and absence of potential environmental pollutants. In addition, LIBs have been widely used as power sources for portable electronic devices and hybrid electric vehicles. [0003] Considering the limitation of energy capacity, the theoretical capacity of commercial graphite electrodes (372mAh g -1 ) can no longer meet the requirements of the existing energy demand, silicon (Si) as the anode material of the next generation o...

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): H01M4/1395H01M4/62H01M4/134H01M10/0525
CPCH01M4/134H01M4/1395H01M4/628H01M10/0525H01M2004/021H01M2004/027Y02E60/10
Inventor 陈仕谋王如梦刘玉文张锁江
Owner INST OF PROCESS ENG CHINESE ACAD OF SCI
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