A kind of polymer coating diaphragm and preparation method thereof

A polymer coating, polymer technology, applied in the direction of structural parts, electrical components, battery pack components, etc., can solve the problem of insignificant improvement in heat resistance, unfavorable rapid mass production, poor stability of oil-based slurry, etc. problem, to achieve the effect of not easy to fall off, improve ion permeability, and improve safety performance

Active Publication Date: 2020-08-28
深圳市鼎泰祥新能源科技有限公司
View PDF13 Cites 0 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

CN105336901A provides a method for preparing a high-performance interpore coated diaphragm, that is, the high-temperature-resistant polymer is configured into a low-concentration oil-based slurry, and applied to the base film in the form of dip coating. This method does not increase the thickness of the diaphragm, and the operation Simple, but due to the poor solubility of such high-temperature-resistant polymers in the solvent, the stability of the oil-based slurry is poor, and there is a phenomenon of powder falling in the composite diaphragm, so that the improvement of heat resistance is not obvious
CN103531736A prepares heat-resistant fibers such as aromatic polyamide into slurry, and prepares a heat-resistant coating through the steps of coating, pre-forming holes, solidifying, washing and drying, although this method can make the fusing temperature of the diaphragm higher than 210 ° C, However, the method is cumbersome and time-consuming, which is not conducive to rapid and large-scale industrial production, and the slurry is not stable enough.

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 kind of polymer coating diaphragm and preparation method thereof
  • A kind of polymer coating diaphragm and preparation method thereof
  • A kind of polymer coating diaphragm and preparation method thereof

Examples

Experimental program
Comparison scheme
Effect test

Embodiment 1

[0036] A polymer coated separator prepared by the following method

[0037] (1) 10g weight average molecular weight Mw is 1.2×10 5 , polyetherimide with molecular weight distribution Mw / Mn of 2 and 1.6g polyvinylidene fluoride were added to 55g N,N-dimethylacetamide and 6.5g ionic liquid [BMIM]BF 4 In the mixed solvent of composition, stir and dissolve at 80 ℃. After the dissolution is complete, add 1.3g polyethylene glycol and 0.6g Tween 80, continue heating and stirring until completely dissolved, then cool and stand for 1 hour.

[0038] (2) Coat both sides of the polyethylene microporous membrane with the prepared coating solution, and place it in a constant temperature and humidity chamber with a temperature of 60°C and a humidity of 80% for 5 minutes to form pores by using the respiration pattern method, and then use deionization Wash with water, and finally dry the diaphragm in hot air at 75°C to obtain a composite diaphragm.

Embodiment 2

[0042] A polymer coated separator prepared by the following method

[0043] (1) The 10g weight average molecular weight Mw is 8×10 4 , polyacrylonitrile with a molecular weight distribution of Mw / Mn of 4 and 2g of vinylidene fluoride-hexafluoropropylene copolymer were added to 40g of N,N-dimethylformamide and 4.5g of ionic liquid [EMIM]AlCl 4 In the mixed solvent of composition, stir and dissolve at 70 ℃. After the dissolution is complete, add 1.5g polyvinylpyrrolidone and 0.4g Tween 60, continue heating and stirring until completely dissolved, then cool and stand for 1.5h.

[0044] (2) Put the prepared coating solution on both sides of the polypropylene microporous membrane after standing for 24 hours, and use the respiration pattern method to make holes, that is, place it in a constant temperature and humidity box with a temperature of 65°C and a humidity of 85%. The pores were formed for 4 minutes, washed with deionized water, and then the membrane was dried in hot air at...

Embodiment 3

[0048] A polymer coated separator prepared by the following method

[0049] (1) The 10g weight average molecular weight Mw is 8×10 4 , molecular weight distribution Mw / Mn is 2 polym-phenylene isophthalamide and 2g polyvinylidene fluoride joins 70g N-methylpyrrolidone and 6.5g ionic liquid [CPMIm]NTf 2 in a mixed solvent, stirred and dissolved at 80°C. After the dissolution is complete, add 1g of polyvinylpyrrolidone and 0.5g of Tween 60, continue heating and stirring until completely dissolved, then cool and stand for 1h.

[0050] (2) Coat the prepared coating solution on both sides of the polyethylene microporous membrane, and use the respiration pattern method to make holes, that is, place it in a constant temperature and humidity box with a temperature of 60 ° C and a humidity of 80% for 5 minutes, and use Wash with deionized water, and finally dry the diaphragm in hot air at 75°C to obtain a composite diaphragm.

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
melting pointaaaaaaaaaa
thermal resistanceaaaaaaaaaa
quality scoreaaaaaaaaaa
Login to view more

Abstract

The invention discloses a polymer coating separator and a preparation method thereof. The polymer coating separator comprises a polyolefin micropore membrane and a polymer coating, wherein the polymer coating is form from polymer coating paste coated on the polyolefin micropore membrane, and the polymer coating paste comprises the following raw materials based on parts by mass: 100 parts of main polymer, 10-30 parts of auxiliary polymer, 300-900 parts of mixed solvent, 5-20 parts of pore-forming agent and 3-10 parts of surfactant. Since the polymer coating paste employs the auxiliary polymer and the mixed solvent containing an ionic liquid, the polymer coating paste is high in stability, and the polymer coating is high in adhesion and is difficult to fall off; and the production of the polymer coating separator cannot be affected even standing for 72 hours, the product performance cannot be affected after standing for 48 hours, the composite separator is endowed with functions of thermal insulation, lyophilicity and the like by the polymer coating, and the safety performance and the ion permeability of the separator are improved.

Description

technical field [0001] The invention relates to the technical field of lithium-ion battery separators, in particular to a polymer-coated separator and a preparation method thereof. Background technique [0002] Due to the advantages of high working voltage, high energy density, no memory effect and long cycle life, lithium-ion batteries have been widely used in portable digital devices, power tools and electric vehicles. [0003] The diaphragm is an indispensable part of the lithium-ion battery. Its main function is to isolate the positive and negative electrodes to prevent direct contact and short circuit, while allowing the ions in the electrolyte to pass freely. The performance of the separator will affect the internal resistance of the battery and the structure of the battery interface, thereby affecting the energy output, power output, and cycle life of the lithium-ion battery. Therefore, lithium-ion battery separators should have good electronic insulation, thermal st...

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 Patents(China)
IPC IPC(8): H01M2/14H01M2/16
CPCH01M50/403H01M50/411Y02E60/10
Inventor 朱赟黄美容王松钊蔡朝辉
Owner 深圳市鼎泰祥新能源科技有限公司
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