Lithium ion battery diaphragm as well as lithium ion battery

A lithium-ion battery and separator technology, which is applied in secondary batteries, battery pack components, non-aqueous electrolyte storage batteries, etc., can solve problems such as not taking into account differences, performance degradation of lithium-ion batteries, and impact on performance of lithium-ion batteries. Achieve the effect of reducing DC internal resistance and excellent performance

Active Publication Date: 2018-10-23
SUNWODA ELECTRIC VEHICLE BATTERY CO LTD
View PDF4 Cites 6 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

However, organic coatings coated on the separator / positive electrode and separator / negative electrode interfaces have different effects on the performance of lithium-ion batteries.
This symmetrical coating only considers the overall performance in lithium-ion batteries. Although it can reduce costs, it does not take into account the difference in the impact of the organic coating on the two interfaces of the separator / positive electrode and the separator / negative electrode on the performance of lithium-ion batteries. Therefore, the DC internal resistance of the lithium-ion battery increases more, resulting in a decline in the performance of the lithium-ion battery

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

Examples

Experimental program
Comparison scheme
Effect test

preparation example Construction

[0032] The process flow of the preparation method of the diaphragm in the embodiment of the present invention is as follows:

[0033] S1: Select a diaphragm substrate with a specified thickness range.

[0034] For example, the base material of the separator is selected as one of polypropylene, polyethylene, polypropylene / polyethylene / polypropylene three-layer composite film and the like as the base material of the separator. Its thickness is 5um-25um.

[0035] S2: After stirring and dispersing the ceramic particles in an aqueous solvent or an organic solvent under certain process conditions, a ceramic slurry is formed.

[0036] For example, disperse alumina with a particle size range of 0.2um-3um in water or N-methylpyrrolidone or acetone, and add a binder and a dispersant, and then stir and disperse according to certain process conditions to form a ceramic slurry .

[0037]S3: Dispersing the organic polymer in a designated solvent, stirring evenly according to the first pr...

Embodiment 1

[0054] A polyolefin with a thickness of 15um is selected as the diaphragm substrate; the thermally stable filler alumina ceramic powder with a particle size range of 0.8um and the thickener carboxymethyl cellulose and the binder acrylonitrile multi-polymer are in a mass ratio of 90: Mix 4:6 in deionized water for 3 hours to obtain a ceramic coating slurry. The measured viscosity of the ceramic slurry can be discharged within the range of 50-500mPa.s; the organic polymer polyvinylidene fluoride-hexafluoropropylene Copolymer and thickener carboxymethyl cellulose and binder acrylonitrile multi-polymer were mixed in deionized water for 4 hours at a mass ratio of 95:2:3 to make the first organic slurry, and the measured viscosity was 20 The material can be discharged within the range of ~500mPa.s; the organic polymer polyvinylidene fluoride-hexafluoropropylene copolymer, the thickener carboxymethyl cellulose and the binder acrylonitrile multi-polymer are in a mass ratio of 93:2: 5 ...

Embodiment 2

[0060] The difference from Example 1 is that the surface density of the formed first organic coating layer and the second organic coating layer are different. In Example 2, the above-mentioned first organic slurry is coated on the surface containing the above-mentioned aluminum oxide by micro-gravure. On one side of the separator substrate with ceramic coating, the surface density is 2g / m 2 The first organic coating layer, the above-mentioned second organic slurry is coated on the other side of the separator substrate without the above-mentioned alumina ceramic coating by means of micro-gravure, forming a surface density of 1g / m 2 the second organic coating. The rest are the same as in Example 1 to form a lithium ion battery 2.

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
viscosityaaaaaaaaaa
viscosityaaaaaaaaaa
viscosityaaaaaaaaaa
Login to view more

Abstract

The invention discloses a lithium ion battery diaphragm as well as a lithium ion battery. The lithium ion battery diaphragm includes a diaphragm base material and non-symmetric organic coatings comprising a first organic coating and a second organic coating, which are formed by respectively coating both surfaces of the diaphragm base material with organic polymers; herein, the first organic coating and the second organic coating include non-symmetric organic coatings, which are prepared from the same organic polymer but are in different surface densities, or include non-symmetric organic coatings, which are prepared from different organic polymers but are in the same surface densities, or include non-symmetric organic coatings, which are prepared from different organic polymers and are indifferent surface densities. In the invention, by coating the both surface of the diaphragm base material with the non-symmetric organic coatings, direct current internal resistance of the lithium ionbattery is reduced on the basis of satisfying the adhesivity between positive and negative plates of the lithium ion battery, so that the lithium ion battery has better performances.

Description

technical field [0001] The invention relates to the technical field of lithium ion batteries, in particular to a lithium ion battery diaphragm and a lithium ion battery. Background technique [0002] Existing lithium-ion batteries are mainly composed of positive electrode materials, negative electrode materials, separators, and electrolytes. The diaphragm is one of the core key materials of lithium-ion batteries. In lithium-ion batteries, the separator mainly plays the role of preventing positive and negative electrodes from contacting and allowing ion conduction. [0003] At present, the existing commercial lithium-ion batteries mainly adopt polyolefin diaphragm materials with microporous structure, and then add inorganic and organic coatings on the surface. Organic coatings can be divided into single and double sides. When using single-sided organic coatings, only one of the two interfaces of the separator / positive electrode or separator / negative electrode can be guarant...

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): H01M2/14H01M2/16H01M10/0525H01M10/058
CPCH01M10/0525H01M10/058H01M50/403H01M50/411H01M50/431H01M50/449Y02E60/10Y02P70/50
Inventor 李国龙张耀陈辉
Owner SUNWODA ELECTRIC VEHICLE BATTERY CO LTD
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