Lithium ion battery diaphragm, preparation method and lithium ion battery

A technology for lithium batteries and diaphragms, which is applied in the field of preparation and diaphragms for lithium batteries. It can solve the problems of unresolved battery safety issues, aggravated battery thermal runaway, and inability to maintain the original form, so as to avoid continuous expansion of thermal runaway and facilitate large-scale industrialization. Production, low heat shrinkage effect

Inactive Publication Date: 2018-06-12
GUANGZHOU GREAT POWER ENERGY & TECH CO LTD
View PDF3 Cites 7 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

Although the thermal shrinkage rate and high temperature resistance of the improved separator have been improved to a certain extent, the characteristics of the substrate determine that these two separators cannot solve the safety problem of the battery. Often when the substrate is not closed and partitioned, the rupture of the separator cannot be maintained. In the original form, the thermal runaway of the battery will be exacerbated, eventually causing the battery to explode or burn
All in all, the safety performance of the existing separators for lithium batteries has not yet achieved a relatively ideal effect, and needs to be further improved and enhanced.

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, preparation method and lithium ion battery
  • Lithium ion battery diaphragm, preparation method and lithium ion battery
  • Lithium ion battery diaphragm, preparation method and lithium ion battery

Examples

Experimental program
Comparison scheme
Effect test

preparation example Construction

[0047] In the second aspect, in some embodiments, a method for preparing the above-mentioned separator for lithium batteries is provided, comprising the following steps:

[0048] (a) Coating the surface of the high molecular polymer membrane or the polytetrafluoroethylene microporous membrane with an adhesive, or soaking the high molecular polymer membrane or the polytetrafluoroethylene microporous membrane in the adhesive;

[0049] (b) Adhering the film with the adhesive on the surface to another film, compacting and drying to obtain the lithium battery separator.

[0050] The above method is simple, practical and easy to implement, that is, one of the sub-membranes is first coated with an adhesive or soaked in the adhesive, and then the film is adhered to the other sub-membrane, compacted and then dried to obtain the obtained product. The separator for the lithium battery described above, and the prepared separator has the advantages of good safety performance, excellent ele...

Embodiment 1

[0070] A diaphragm for a lithium battery has a double-layer film structure, including a high molecular polymer film and a polytetrafluoroethylene microporous film, and an adhesive is coated between the high molecular polymer film and the polytetrafluoroethylene microporous film.

[0071] Wherein, the polymer film is PE film, the polytetrafluoroethylene microporous film is ePTFE film, and the binder is PVDF-HFP solution.

[0072] The preparation method of described diaphragm for lithium battery comprises the following steps:

[0073] (a) Soak the polytetrafluoroethylene microporous membrane in ethanol, take it out after soaking for 5 minutes, then soak it in the PVDF-HFP solution with a mass percentage content of 2%, take it out after soaking for 30 minutes;

[0074] (b) Paste the soaked ePTFE membrane directly on the PE membrane;

[0075] (c) After being compacted, vacuum-dry at 60° C. for 30 minutes, and take out after complete drying to obtain a separator for lithium batter...

Embodiment 2

[0077] A diaphragm for a lithium battery has a double-layer film structure, including a high molecular polymer film and a polytetrafluoroethylene microporous film, and an adhesive is coated between the high molecular polymer film and the polytetrafluoroethylene microporous film.

[0078] Wherein, the polymer film is PP film, the polytetrafluoroethylene microporous film is ePTFE film, and the binder is PVDF-HFP solution.

[0079] The difference between this embodiment and embodiment 1 is that the PE film is replaced by a PP film.

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

No PUM Login to view more

Abstract

The invention belongs to the technical field of lithium ion batteries and relates to a lithium ion battery diaphragm, a preparation method and a lithium ion battery. The lithium battery diaphragm provided by the invention is of a two-layer film structure which comprises a high-molecular polymer film and a polytetrafluoroethylene microporous film; a binder is applied between the high-molecular polymer film and the polytetrafluoroethylene microporous film. The diaphragm provided by the invention integrates the advantages of both sub-films, including a closing function at relatively low temperature, fairly strong strength and excellent high-temperature resistance; the diaphragm can be used stably at 200 DEG C, a complete structure is maintained at 250 DEG C, the safety performance of the battery is remarkably enhanced, and the safety of the battery is guaranteed in needling, impact and other unfavorable conditions.

Description

technical field [0001] The invention belongs to the technical field of lithium ion batteries, and in particular relates to a separator for lithium batteries, a preparation method and a lithium ion battery. Background technique [0002] In the existing secondary battery system, whether in terms of development space or technical indicators such as life, specific energy, working voltage and self-discharge rate, lithium-ion batteries are currently the most competitive secondary batteries, and are regarded as the most competitive secondary batteries. Widely used in various fields. With the continuous development of electronic technology, higher requirements are put forward for lithium-ion batteries, which require higher energy density, better cycle life, better high and low temperature charge and discharge performance and safety performance. [0003] With the improvement of the energy density of the existing lithium-ion battery, its safety performance is also greatly affected. F...

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): H01M2/16H01M10/0525H01M50/409
CPCH01M10/0525H01M50/409Y02E60/10
Inventor 崔燕陈家辉薛建军周意君
Owner GUANGZHOU GREAT POWER ENERGY & TECH 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