Lithium ion secondary battery and preparation method thereof

A secondary battery and lithium-ion technology, applied in the direction of secondary batteries, battery electrodes, battery components, etc., can solve problems such as limited capacity and inability to meet the needs of large-capacity batteries

Inactive Publication Date: 2010-02-17
BYD CO LTD
View PDF1 Cites 19 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

However, the capacity increased by this method is limited and cannot me

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

Examples

Experimental program
Comparison scheme
Effect test

preparation example Construction

[0029] The preparation method of the positive electrode can adopt various methods commonly used in the art, such as preparing the positive electrode active material, binder and conductive agent into a positive electrode material slurry with a solvent, and the addition amount of the solvent is well known to those skilled in the art. The viscosity and operability requirements of the slurry coating of the prepared positive electrode slurry can be flexibly adjusted. Then, the prepared positive electrode material slurry is drawn and coated on the positive electrode current collector, dried and pressed into sheets, and then cut into pieces to obtain positive electrodes. The drying temperature may be 80-150° C., and the drying time may be 2-10 hours.

[0030] The solvent used in the positive electrode slurry can be various solvents in the prior art, such as N-methylpyrrolidone (NMP), dimethylformamide (DMF), diethylformamide (DEF), diethylformamide (DEF), One or more of methyl sulfo...

Embodiment 1

[0036] This embodiment is used to illustrate the lithium ion secondary battery provided by the present invention.

[0037] Positive electrode: the positive active material LiCoO 2 , Conductive agent acetylene black, conductive polymer (cationized product of polyaniline, conductivity 10S / cm, EHSY company) as binder, mix thoroughly with solvent NMP by weight ratio 100:5:2. Spread the dressing on both sides on aluminum foil with a thickness of 20 μm and spread evenly. Dried at 100°C, rolled, rolled and cut into positive electrode sheets, the size of the electrode sheet was 450cm (length)×44cm (width)×0.12cm (thickness), containing 7 grams of positive electrode active material.

[0038] Negative electrode: uniformly mix artificial graphite, binder SBR and CMC in deionized water at a weight ratio of 100:5:3. Apply double-sided dressing on copper foil with a thickness of 12 microns and spread evenly. Dry at 90°C, roll, roll and cut into positive pole pieces, the size of which is ...

Embodiment 2

[0042] This embodiment is used to illustrate the lithium ion secondary battery provided by the present invention.

[0043] Positive electrode: the positive active material LiCoO 2 , Conductive agent acetylene black, conductive polymer (cationized product of polythiophene, EHSY company, conductivity 8S / cm) as binder, mix thoroughly with NMP by weight ratio 100:5:0.5. Spread the dressing on both sides on aluminum foil with a thickness of 20 μm and spread evenly. Dry at 100°C, roll, roll and cut into positive electrode pieces, the size of the electrode piece is 450cm×44cm, and the weight of the positive electrode material is 7 grams.

[0044] Negative electrode: proceed according to the method for preparing the negative electrode in Example 1.

[0045] Diaphragm: A 25 micron thick polyimide porous film with a porosity of 60% and an average pore diameter of 80 nanometers.

[0046] Battery 2 was assembled according to the method of Example 1.

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
Average pore diameteraaaaaaaaaa
Thicknessaaaaaaaaaa
Average pore diameteraaaaaaaaaa
Login to view more

Abstract

The invention provides a lithium ion secondary battery. The lithium ion battery comprises a battery shell, a pole core and an electrolyte, wherein the pole core and the electrolyte are accommodated inthe battery shell; the pole core comprises a positive pole, a negative pole and a diaphragm positioned between the positive pole and the negative pole; the positive pole comprises a current collectorand positive materials; the positive materials comprise positive active substances, a conductive agent and a binder; the binder is provided with conductive performance; and the diaphragm is a porouspolyimide film. The invention also provides a preparation method for the lithium ion secondary battery. Due to the adoption of a conductive polymer serving as the positive binder and polyimide servingas the battery diaphragm, the lithium ion secondary battery provided by the invention significantly increases the capacity and the cycle performance of the battery, and significantly improves the high-rate charge and discharge performance.

Description

technical field [0001] The invention relates to a lithium ion secondary battery and a preparation method thereof. Background technique [0002] In recent years, the rapid development of electronic technology has enabled electronic devices to be miniaturized and light in weight, and thus more and more portable electronic devices have appeared. Lithium-ion secondary batteries have become the preferred energy sources for these portable electronic devices due to their advantages of high discharge voltage, high energy density and long cycle life. [0003] The capacity and cycle performance of lithium-ion secondary batteries are the main performance indicators of lithium-ion secondary batteries, and the capacity and cycle performance are greatly affected by the resistance of the battery. A lithium-ion secondary battery is mainly composed of a positive electrode, a negative electrode, a separator, and an electrolyte. The positive electrode includes a current collector and a posit...

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): H01M10/40H01M4/62H01M2/16H01M10/38
Inventor 黄艺凤马鲁飞吴声本姜占锋
Owner BYD 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