Unlock instant, AI-driven research and patent intelligence for your innovation.

A kind of self-stabilizing p (vdf-hfp) slurry and its preparation method and lithium ion battery diaphragm

A VDF-HFP, lithium-ion battery technology, applied in battery pack parts, circuits, electrical components, etc., can solve the problems of non-dispersion, battery consistency, safety hazards, etc., to promote dispersion, improve performance and safety performance , the effect of increasing the surface free energy

Active Publication Date: 2021-04-09
HEFEI GUOXUAN HIGH TECH POWER ENERGY
View PDF2 Cites 0 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

Although this method has certain advantages, there are also many defects. On the one hand, the hydrogen bonds formed in the P(VDF-HFP) molecular chain are very strong, and the electronegativity of oxygen in water is not enough to separate the hydrogen bonds, resulting in P(VDF-HFP) is basically not dispersed in water, so a surfactant needs to be added to reduce the surface tension of water and increase the surface free energy of P(VDF-HFP); on the other hand, a binder needs to be added to the slurry to Realize the bonding between P(VDF-HFP) and polyolefin separator to prevent powder falling
However, the introduction of surfactants and binders may dissolve under the long-term infiltration of the electrolyte, which poses potential safety hazards to the consistency of the battery, especially the safety.

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
  • A kind of self-stabilizing p (vdf-hfp) slurry and its preparation method and lithium ion battery diaphragm

Examples

Experimental program
Comparison scheme
Effect test

preparation example Construction

[0022] The invention discloses a preparation method of self-stabilizing P(VDF-HFP) slurry, comprising the following steps:

[0023] a. Add acrylic acid monomer and polymerization inhibitor to deionized water for mixing and dissolving, then add P(VDF-HFP) powder to obtain a mixed system;

[0024] b. Pass inert gas into the mixed system to get rid of the air in the mixed system, and then keep it sealed;

[0025] c. Put the mixed system sealed and preserved in step b into 60 Irradiate in a Coγ-ray irradiation device to obtain a dispersion;

[0026] d. After the dispersion liquid is centrifuged and washed with water, it is redispersed in deionized water to prepare a self-stabilizing P(VDF-HFP) slurry.

[0027] Make self-stabilizing P (VDF-HFP) slurry by the preparation method among the present invention, on the one hand because its surface is grafted with PAA, therefore can serve as dispersant, promotes P (VDF-HFP) microsphere well in water Dispersion; on the other hand, the gr...

Embodiment 1

[0038] a. Add 5g of acrylic acid monomer and 0.25g of ferrous sulfate heptahydrate into 50ml of deionized water to mix and dissolve, then add 1.5g of P(VDF-HFP) powder to obtain a mixed system;

[0039] b. Infuse nitrogen into the mixing system for 30 minutes to remove the air in the mixing system, and then seal it for storage;

[0040] c. Put the mixed system sealed and preserved in step b into 60 In the Coγ-ray irradiation device, the irradiation dose rate is 9Gy / min for 24h, and the total absorbed dose of irradiation is 13kGy to obtain the dispersion liquid;

[0041] d. After the dispersion liquid was centrifuged and washed 6 times, it was redispersed in 30ml deionized water to make a self-stabilizing P(VDF-HFP) slurry with a solid content of 1%;

[0042] f. Coat the self-stabilizing P (VDF-HFP) slurry on the surface of polyolefin or polyolefin separator coated with ceramics using a micro gravure roll to obtain a lithium-ion battery separator with a coating thickness of 0....

Embodiment 2

[0044] a. Add 15g of acrylic acid monomer and 0.5g of copper sulfate into 100ml of deionized water to mix and dissolve, then add 4g of P(VDF-HFP) powder to obtain a mixed system;

[0045] b. Infuse nitrogen gas into the mixing system for 25 minutes to remove the air in the mixing system, and then seal it for storage;

[0046] c. Put the mixed system sealed and preserved in step b into 60In the Coγ-ray irradiation device, the irradiation dose rate is 6Gy / min for 40h, and the total absorbed dose of irradiation is 50kGy to obtain the dispersion liquid;

[0047] d. After the dispersion liquid was centrifuged and washed 5 times, it was redispersed in 40ml deionized water to make a self-stabilizing P(VDF-HFP) slurry with a solid content of 5%;

[0048] f. Coat the self-stabilizing P (VDF-HFP) slurry on the surface of polyolefin or polyolefin separator coated with ceramics by micro gravure roll to obtain lithium ion battery separator, the coating thickness is 1 μm, and the coated su...

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 discloses a preparation method of self-stabilizing P(VDF-HFP) slurry, adding acrylic acid monomers and polymerization inhibitors into deionized water to mix and dissolve, and then adding P(VDF-HFP) powder to obtain a mixed system; Pass inert gas into the mixed system to get rid of the air in the mixed system, and then keep it sealed; put the mixed system sealed and preserved in step b into 60 Irradiate in a Coγ-ray irradiation chamber to obtain a dispersion; the dispersion is centrifugally washed and then redispersed in deionized water to prepare a self-stabilizing P(VDF-HFP) slurry. The slurry prepared by the present invention does not need to add any surfactants and binders, and it is used to coat lithium-ion battery separators without worrying about the performance degradation and degradation caused by the dissolution of surfactants and binders in the electrolyte. Potential safety hazards, fundamentally improve the performance and safety performance of lithium-ion batteries.

Description

technical field [0001] The invention relates to the field of lithium-ion battery separators, in particular to a self-stabilizing P(VDF-HFP) slurry and a preparation method thereof, and also to a lithium-ion battery separator. Background technique [0002] In recent years, with the rise of new energy vehicles as an emerging strategic industry, power lithium-ion batteries with high energy density, excellent safety, and excellent cruising range have attracted more and more attention. As one of the four key main materials of lithium-ion batteries (positive electrode, negative electrode, diaphragm, and electrolyte), the separator mainly plays the role of isolating the positive and negative electrodes and allowing lithium ions to pass freely. Although the separator does not participate in the electrochemical reaction in the battery, it directly affects the capacity, cycle performance and safety performance of the battery. With the improvement of battery energy density, especially...

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): C08F259/08C09D151/00C08F220/06H01M50/417H01M50/403H01M50/443
CPCC09D151/003C08F259/08H01M50/403H01M50/411C08F220/06Y02E60/10
Inventor 汪杰陈萌谢玉虎宋仲海
Owner HEFEI GUOXUAN HIGH TECH POWER ENERGY