Composite diaphragm as well as preparation method and application thereof

A composite diaphragm and diaphragm material technology, applied in the field of lithium-ion batteries, can solve the problems of increasing the manufacturing cost of ceramic diaphragms, high toxicity of organic solvents, flammable and volatile safety, etc.

Inactive Publication Date: 2014-09-24
XIAMEN UNIV +1
View PDF9 Cites 36 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

The binder is mainly a polymer compound, such as polyvinylidene fluoride (PVDF), polyvinylidene fluoride-hexafluoropropylene copolymer (PVDF-HFP), polymethyl methacrylate (PMMA), etc.,

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
  • Composite diaphragm as well as preparation method and application thereof
  • Composite diaphragm as well as preparation method and application thereof
  • Composite diaphragm as well as preparation method and application thereof

Examples

Experimental program
Comparison scheme
Effect test

Example Embodiment

[0052] Example 1

[0053] The synthesized alumina nanoparticles, sodium carboxymethyl cellulose (CMC) and styrene butadiene rubber (SBR) with a mass ratio of 95:2:3 mixed powder 1g, put in deionized water and acetone (3:1, v : V) 10ml of mixed solution, ball mill the resulting ceramic slurry overnight, ultrasonically disperse the mixed slurry for 20 minutes, and apply the resulting slurry to diaphragm coating. The ceramic diaphragm is made of ordinary polyethylene (PE) diaphragm as the diaphragm substrate. The obtained slurry is evenly coated on one side or both sides of an ordinary polyethylene (PE) separator. Use an electric heating plate to preheat at 60°C, and after most of the solvent is volatilized, put it in a vacuum oven at 60°C to dry overnight to completely remove the solvent to obtain a modified ceramic diaphragm.

[0054] figure 1 In order to obtain a scanning electron micrograph of a composite diaphragm with alumina as an inorganic powder, it can be clearly observed...

Example Embodiment

[0055] Example 2

[0056] Mix 1g of synthesized silica nanoparticles and polyacrylate terpolymer latex (LA132) with a mass ratio of 90:4:6, and put deionized water and ethanol solvent (3:1, v:v) mixed solvent 15ml, ball mill the resulting ceramic slurry overnight, ultrasonically disperse the mixed slurry for 30 minutes, and apply the resulting slurry to diaphragm coating. The ceramic diaphragm is made of ordinary polypropylene (PP) diaphragm as the diaphragm substrate. The obtained slurry is uniformly coated on one side or both sides of an ordinary polyethylene (PP) separator. Use an electric heating plate to preheat at 60°C, and after most of the solvent is volatilized, put it in a vacuum oven at 60°C to dry overnight to completely remove the solvent to obtain a modified ceramic diaphragm.

[0057] figure 2 In order to prepare the SEM picture of the composite diaphragm with silica as inorganic powder, it can be clearly observed that the silica powder is evenly spread on the sur...

Example Embodiment

[0059] Example 3

[0060] The synthesized magnesium oxide nanoparticles and polyacrylate terpolymer latex (LA133) with a mass ratio of 85:6:9 mixed powder 1g, put in a suitable ratio of deionized water and acetone (3:1, v:v ) Mix 20 ml of solvent, ball mill the resulting ceramic slurry overnight, ultrasonically disperse the mixed slurry for 40 minutes, and apply the resulting slurry to diaphragm coating. A ceramic diaphragm is made of polyvinylidene fluoride (PVDF) diaphragm as the diaphragm substrate. The obtained slurry is uniformly coated on one side or both sides of a polyvinylidene fluoride (PVDF) separator. Use an electric heating plate to preheat at 60°C, and after most of the solvent is volatilized, put it in a vacuum oven at 60°C to dry overnight to completely remove the solvent to obtain a modified ceramic diaphragm.

[0061] The heat shrinkage rate diagram of the composite diaphragm of Example 3 before and after heat shrinkage is shown in Figure 4 with 5 .

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 composite diaphragm as well as a preparation method and application thereof, and relates to a lithium ion battery. The composite diaphragm comprises a base diaphragm material; a protective layer coats the surface of the base diaphragm material and adopts a water-soluble bonding agent; a solvent used by slurry of the protective layer is water. The preparation method of the composite diaphragm comprises the steps of (1) evenly mixing inorganic particle powder, the water-soluble bonding agent and the solvent to obtain mixed powder; and (2) coating the single or double surfaces of a common commercially available diaphragm with the mixed powder obtained in the step (1) by a film applicator, carrying out vacuum drying, and removing the solvent to obtain the composite diaphragm, wherein the thickness of the composite diaphragm can be adjusted by controlling the concentration of the slurry and the parameters of the film applicator. The composite diaphragm can be applied to the preparation of a secondary battery and can be used for replacing an existing ceramic diaphragm, wherein the secondary battery comprises but not limited to a lithium ion battery.

Description

technical field [0001] The invention relates to a lithium ion battery, in particular to a composite separator and its preparation method and application. Background technique [0002] At present, chemical power systems using liquid electrolytes, such as lithium-ion batteries, need to use diaphragm materials to block the positive and negative electrodes to avoid short circuits. The diaphragm material is mainly composed of polyethylene (Polyethylene, PE), polypropylene (Polypropylene, PP), polytetrafluoroethylene (Polytetrafluoroethylene, PTFE) and other polymer films or non-woven fabrics containing microporous structures. Liquid electrolyte (generally a carbonate organic solvent containing electrolyte salt) exists in the microporous structure to realize the conduction of ions between the positive and negative electrodes. The separator and liquid electrolyte constitute the electrolyte system. [0003] With the development of fields such as electric vehicles, higher requireme...

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
IPC IPC(8): H01M2/16H01M50/403H01M50/451
CPCH01M10/0525H01M50/446H01M50/403Y02E60/10
Inventor 赵金保张鹏石川
Owner XIAMEN UNIV
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