Looking for breakthrough ideas for innovation challenges? Try Patsnap Eureka!

Diaphragm and preparation method thereof as well as lithium ion battery

A lithium-ion battery and diaphragm technology, which is applied in the direction of secondary batteries, battery pack components, circuits, etc., can solve the problem that the battery cannot achieve high-rate discharge, and achieve good high-rate discharge characteristics, good liquid absorption, and production technology simple effect

Inactive Publication Date: 2012-11-21
BYD CO LTD
View PDF0 Cites 0 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

[0006] In order to solve the problem that batteries with traditional separators cannot achieve high rate discharge

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
  • Diaphragm and preparation method thereof as well as lithium ion battery
  • Diaphragm and preparation method thereof as well as lithium ion battery
  • Diaphragm and preparation method thereof as well as lithium ion battery

Examples

Experimental program
Comparison scheme
Effect test

preparation example Construction

[0026] In the preparation method of the above diaphragm, the organic polymer film-forming material is dissolved in an organic solvent to form a transparent solution, and the solution is coated on the surface of the substrate and dried to prepare the diaphragm.

[0027] The coating adopts coating methods known to those skilled in the art, such as printing, rolling, squeegeeing, dipping, spraying and pulling.

[0028] At the same time, the present invention also provides a lithium ion battery containing the above separator, including a positive electrode, a negative electrode, a separator, and an electrolyte. The positive electrode, the separator and the negative electrode are made into cells by techniques known to those skilled in the art, such as winding or stacking in sequence. Put the cell into the battery casing, inject the electrolyte, and seal the battery to obtain the battery. The electrolyte is an electrolyte known to those skilled in the art; the battery casing is a ca...

Embodiment 1

[0032] (1) Preparation of diaphragm

[0033]Take 2g of PVDF powder, among them, the selected PVDF has a heat-resistant temperature of 170°C and a heat shrinkage rate of 3%, dissolve it in 40g of organic solvent, add 1.5g of plasticizer, and stir at a temperature of 50°C until the powder is completely Dissolve to obtain a colorless and transparent solution, apply the solution on both sides of the PET film by dipping, dry to form a film, and the film thickness is controlled at 2 μm.

[0034] (2) Preparation of battery

[0035] (a) Preparation of positive electrode

[0036] Dissolve 30 grams of polyvinylidene fluoride (PVDF) in 450 grams of N-methylpyrrolidone (NMP) solvent to prepare a binder solution, and then mix 940 grams of LiCoO 2 Add 30 grams of acetylene black powder into the above solution, stir and mix evenly to obtain a positive electrode slurry; use a pulper to evenly coat the positive electrode slurry on both sides of an aluminum foil with a thickness of 18 microns...

Embodiment 2

[0043] A PET composite separator was prepared according to the method of Example 1, except that no plasticizer was added.

[0044] The SL6043122 soft package battery was fabricated according to the method of Example 1, except that the battery separator used was the separator of Example 2.

[0045] Prepare 50 PCS of SL6043122 flexible packaging battery according to the above method.

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
thermal resistanceaaaaaaaaaa
pore sizeaaaaaaaaaa
thicknessaaaaaaaaaa
Login to View More

Abstract

A diaphragm is selected from a composite membrane containing polyethylene terephthalate membrane as the base material. The composite membrane contains at least one organic polymer membrane consisting of polymer film-forming materials with a thermal resistant temperature of 170 DEG C to 500 DEG C and heat shrinkage of 0% to 5%. Preferably, a plasticizer is added during solution preparation to achieve more uniform pore distribution so as to obtain the composite membrane with excellent performance. The diaphragm has high temperature resistance and high safety when used for battery diaphragm. In addition, the diaphragm has good solution adsorption performance, so that the diaphragm can adsorb the electrolyte to improve the circle performance of the battery. The invention also provides the diaphragm preparation method, which is simple and convenient. Compared with the conventional battery and the battery using PET composite diaphragm with inorganic coating, the battery using the diaphragm has higher capacity, better high-rate discharge characteristics and low-temperature discharger performance, no flame and liquid leakage during high-temperature test, and excellent high-temperature safety performance.

Description

【Technical field】 [0001] The invention relates to a diaphragm, a preparation method thereof and a lithium ion battery. 【Background technique】 [0002] Separators are a key component of lithium-ion batteries. Separators for Li-ion batteries are usually thin porous insulating materials with high ion permeability, good mechanical strength, and long-term stability to various chemicals and chemical solvents. When a large current is generated inside the battery due to an external short circuit or wrong connection, and the internal temperature of the battery rises to the closed cell temperature of the diaphragm, the diaphragm will be thermally melted and the micropore structure will be closed, thereby cutting off the current and ensuring the safety of the battery. The performance of the separator determines the interface structure and internal resistance of the battery, which in turn affects the key characteristics of the battery such as capacity, cycle, charge and discharge curre...

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): H01M2/16C08J5/22H01M10/40H01M50/403H01M50/411H01M50/417H01M50/42H01M50/426H01M50/491
CPCY02E60/12H01M2/1653H01M2/162Y02E60/10H01M50/44H01M50/417H01M50/42H01M50/426
Inventor 武汉辉梁世硕
Owner BYD CO LTD
Who we serve
  • R&D Engineer
  • R&D Manager
  • IP Professional
Why Patsnap Eureka
  • Industry Leading Data Capabilities
  • Powerful AI technology
  • Patent DNA Extraction
Social media
Patsnap Eureka Blog
Learn More
PatSnap group products

Browse by: Latest US Patents, China's latest patents, Technical Efficacy Thesaurus, Application Domain, Technology Topic, Popular Technical Reports.

© 2024 PatSnap. All rights reserved.Legal|Privacy policy|Modern Slavery Act Transparency Statement|Sitemap|About US| Contact US: help@patsnap.com