Copolymer latex for negative electrode of lithium ion secondary battery, preparation method and application

A copolymer latex, lithium-ion battery technology, applied in secondary batteries, battery electrodes, circuits, etc., can solve the problems of low cohesion between electrode active materials and current collectors, affecting battery capacity, etc., and improve resistance to electrolyte swelling. The effect of improving the adhesion, reducing the dosage

Active Publication Date: 2020-10-27
RIZHAO GUANGDA BUILDING MATERIALS
View PDF5 Cites 4 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

Oil-based binders are mainly polyvinylidene fluoride polymers. Due to their low binding force to electrode active materials and current

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
  • Copolymer latex for negative electrode of lithium ion secondary battery, preparation method and application
  • Copolymer latex for negative electrode of lithium ion secondary battery, preparation method and application

Examples

Experimental program
Comparison scheme
Effect test

Embodiment 1~7

[0037] A kind of copolymer latex for negative electrode of lithium ion secondary battery, specific formula is shown in Table 1.

[0038] Produced by seed emulsion polymerization method, the specific method is as follows:

[0039] (1) fully stirring and mixing the styrene, butadiene, unsaturated carboxylic acid monomer and emulsifier, deionized water of formula quantity, obtains the core layer monomer pre-emulsion;

[0040] (2) butadiene, styrene, ethylenically unsaturated monomer of formula quantity are fully stirred and mixed with emulsifier and deionized water to obtain shell monomer pre-emulsion;

[0041] (3) After mixing 40% of the total mass of the nuclear layer monomer pre-emulsion obtained in step (1) with the first part of the pH regulator and the first part of the initiator, stir and heat up to 72 ° C, and keep stirring for 5 hours to obtain the nuclear seed microemulsion;

[0042] (4) First raise the temperature of the nuclear seed microemulsion prepared in step (3) ...

Embodiment 8

[0050] A kind of copolymer latex for negative electrode of lithium ion secondary battery, the latex particle contained in it has hard core soft shell structure, and average particle diameter is 100nm, by weight, described hard core is made of 80 parts of styrene, 15 parts of butyl A polymer formed by copolymerization of diene and 1 part of unsaturated carboxylic acid monomer. The glass transition temperature of the hard core is above 60°C. The soft shell is composed of 80 parts of butadiene, 20 parts of styrene, and 30 parts of vinyl A polymer formed by copolymerization of unsaturated monomers and 0.5 parts of nitrogen-sulfur-fluorine co-doped carbon nanotubes, wherein the hard core and soft shell account for 20% and 80% of the latex particle weight respectively.

[0051] The unsaturated carboxylic acid is acrylic acid.

[0052] The ethylenically unsaturated monomer is methyl acrylate.

[0053] In parts by weight, the hard core is a polymer formed by copolymerization of 100 p...

Embodiment 9

[0065] A kind of copolymer latex for negative electrode of lithium ion secondary battery, the latex particle contained in it has hard core soft shell structure, and average particle diameter is 100nm, and by weight, described hard core is made of 100 parts of styrene, 5 parts of butyl A polymer formed by copolymerization of diene and 5 parts of unsaturated carboxylic acid monomers. The glass transition temperature of the hard core is above 60°C. The soft shell is composed of 30 parts of butadiene, 70 parts of styrene, and 20 parts of vinyl A polymer formed by copolymerization of unsaturated monomers and 0.8 parts of 1-allyl-3-butylimidazolium tetrafluoroborate-modified carbon nanotubes, wherein the hard core and soft shell respectively account for 5% of the weight of latex particles , 95%.

[0066] The unsaturated carboxylic acid is methacrylic acid and maleic acid, and the mass ratio of the two is 1:1.

[0067] The ethylenically unsaturated monomer is octyl acrylate and itac...

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
Glass transition temperatureaaaaaaaaaa
Login to view more

Abstract

The invention discloses copolymer latex for a negative electrode of a lithium ion secondary battery. Firstly, styrene, butadiene and unsaturated carboxylic acid monomers are copolymerized to prepare ahard core, and butadiene, styrene and vinyl unsaturated monomers are copolymerized to prepare a soft shell so that a latex product with a hard core and soft shell structure is prepared, and the latexproduct is particularly suitable for a lithium ion secondary battery negative electrode adhesive. Research finds that the copolymer latex with the polymer particles with the hard-core and soft-shellstructures can improve the cohesiveness so that the dosage of the adhesive is reduced, and the influence of the adhesive on the internal resistance of the battery is reduced. The functional group introduced by copolymerization can change the polarity and dielectric properties of the polymer, thereby improving the electrolyte swelling resistance of the adhesive and the influence on the internal resistance of the battery.

Description

technical field [0001] The invention relates to a copolymer latex for negative electrodes of lithium ion secondary batteries. The invention belongs to the technical field of lithium ion secondary battery technology. Background technique [0002] The negative electrode of lithium ion secondary battery is composed of active material graphite, conductive additive, binder and current collector. The preparation method of the negative electrode is usually to mix and disperse the active material, the conductive additive and the binder with water as the medium to form a uniform slurry, coat it on the copper foil on the current collector, and make it through drying and pressing rolls. [0003] The performance of the binder is one of the important indicators to determine the capacity and life of lithium-ion secondary batteries. As a non-conductive substance, the amount of the binder affects the capacity and internal resistance of the lithium-ion secondary battery. Therefore, the amo...

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): C08F257/02C08F236/10C08F212/08C08F220/14C08F220/46C08F220/06C08F222/02H01M4/62H01M10/0525
CPCC08F257/02H01M4/622H01M10/0525C08F236/10C08F212/08C08F220/14C08F220/46C08F220/06C08F222/02Y02E60/10
Inventor 丁子豪程昌华张荣新郭伟刘江安吕孙单静
Owner RIZHAO GUANGDA BUILDING MATERIALS
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