Lithium ion battery diaphragm and preparation method thereof

A lithium-ion battery and separator technology, applied in the field of preparation of the battery separator, can solve the problems of insufficient flatness and large roughness of the coating separator, and achieve the effects of good flatness, small roughness and reduction of shrinkage cavities

Active Publication Date: 2014-09-17
河南惠强新能源材料科技股份有限公司
View PDF7 Cites 31 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

[0006] In order to solve the problems of insufficient flatness and large roughness of the existing lithium-ion battery coating diaphragm, thereby improving battery assembly efficiency and yield, and improving the cycle life and safety of lithium-ion batteries, the invention provides a lithium-ion battery diaphragm , and the present invention also provides a preparation method of the battery diaphragm

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
  • Lithium ion battery diaphragm and preparation method thereof
  • Lithium ion battery diaphragm and preparation method thereof
  • Lithium ion battery diaphragm and preparation method thereof

Examples

Experimental program
Comparison scheme
Effect test

Embodiment 1

[0044] Dry coating treatment:

[0045] The silane coupling agent is configured as a 1% alcohol-water mixed solution (alcohol:water=1:1).

[0046] Put the first and second magnesium hydroxide flake particles into the circulating air mixer respectively, and mix them under the spray environment of the above mixed solution for 15 hours, dry them, and take them out.

[0047] Grind and disperse the coated first and second magnesium hydroxide flake particles respectively, and filter the agglomerated particles. The average particle diameter of the first magnesium hydroxide flaky particles is 150nm, the particle size distribution range is (60-450)nm, and the aspect ratio of the flaky particles is 1-5; the second magnesium hydroxide flaky particles are measured The average particle size is 1 μm, the particle size distribution range is 450 nm-2.5 μm, and the aspect ratio of the flake particles is 1-5.

Embodiment 2

[0049] Wet Wrap Treatment:

[0050] The first and second magnesium hydroxide flaky particles are respectively configured into 6% slurry (water is a solvent), stirred in a water bath at 70° C., and 1 part of acrylic acid, 90 parts of inorganic particles, 0.1 part of inorganic peroxide and 90 parts of butyl acrylate, coated for 3 hours, suction filtered, washed, dried and taken out.

[0051] Grind and disperse the first and second magnesium hydroxide flake particles respectively, and filter the agglomerated particles. The average particle diameter of the first magnesium hydroxide flaky particles is 150nm, the particle size distribution range is (60-450)nm, and the aspect ratio of the flaky particles is 1-5; the second magnesium hydroxide flaky particles are measured The average particle size is 1 μm, the particle size distribution range is 450nm-3 μm, and the aspect ratio of the flake particles is 1-5.

Embodiment 3

[0053] The inorganic particles treated in Example 1 were used.

[0054] Get 25g of the first magnesium hydroxide flaky particles and 60g of the second magnesium hydroxide flaky particles, 0.6g of PE wax and 1g of polysiloxane mixture, 15g of acrylonitrile emulsion, 0.75g of acrylic leveling agent, 180g of water and 45g of Ethanol is mixed and dispersed evenly to make a suspension coating slurry.

[0055] The above-mentioned suspension coating slurry was coated on one side of a 16 μm ultra-high molecular weight polyethylene substrate, and then dried and solidified to obtain the coated separator for lithium-ion batteries of the present invention. The total thickness of the coating on one side was 4 μm.

[0056] The measured magnesium hydroxide flaky particle angle distribution range is 0~45 °; the first magnesium hydroxide flaky particle is evenly distributed in the second inorganic flaky particle gap, and the compactness is good (see figure 2 ); the appearance of the coating ...

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
The average particle sizeaaaaaaaaaa
Particle sizeaaaaaaaaaa
Particle sizeaaaaaaaaaa
Login to view more

Abstract

The invention relates to a lithium ion battery diaphragm. The lithium ion battery diaphragm comprises a polyolefin substrate and a composite coating, wherein the coating is connected with the polyolefin substrate through a binder, the coating is formed by stacking a plurality of inorganic particle layers, and each two adjacent inorganic particle layers of the coating are connected with each other through a binder; each inorganic particle layer consists of flaky inorganic particles, and the flaky inorganic particles are distributed in parallel or at a small angle in the coating. The invention also relates to a preparation method of the lithium ion battery diaphragm. The preparation method comprises the following steps: preparing flaky inorganic particles; screening first inorganic particles and second inorganic particles; preparing coating slurry; coating the polyolefin substrate with the coating slurry, and drying the polyolefin substrate with the coating to obtain a product. The lithium ion battery diaphragm is high in flatness, low in coarseness, low in water absorption rate, low inn coating expansion degree, capable of effectively reducing the natural crimpness of single-side coated diaphragm and capable of improving the assembling efficiency and rate of finished products of a laminated battery.

Description

technical field [0001] The invention relates to a lithium-ion battery diaphragm, and also relates to a preparation method of the battery diaphragm. Background technique [0002] Lithium-ion secondary batteries are widely used due to their long life and high energy density. The separator is an important part of the lithium-ion battery, which plays the role of isolating the positive and negative electrodes and ion conduction. Most of the separator materials currently on the market are polyolefin materials, mainly including polyethylene and polypropylene. [0003] Due to the difference in thermal properties between polyethylene and polypropylene, the current shutdown temperature (Shut-down temperature) of the separator made of polyethylene is relatively low. When the battery is overloaded, as the temperature rises, the microporous structure inside the separator quickly It is destroyed and melted closed, blocking the current in time. However, the disadvantage is that its melt...

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): H01M2/16H01M2/14H01M50/403H01M50/417H01M50/431H01M50/443H01M50/457H01M50/489
CPCH01M50/403H01M50/446Y02E60/10
Inventor 邱钧锋黄美容吴耀根蔡朝辉廖凯明
Owner 河南惠强新能源材料科技股份有限公司
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