Polyimide composite fiber membrane, preparation method thereof and lithium ion battery

A technology of polyimide fiber and composite fiber membrane, applied in the direction of fiber type, secondary battery, fiber processing, etc., can solve battery safety problems and other issues

Active Publication Date: 2021-07-13
SUNWODA ELECTRIC VEHICLE BATTERY CO LTD
View PDF3 Cites 0 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

However, the traditional polyolefin separators currently on the market are

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
  • Polyimide composite fiber membrane, preparation method thereof and lithium ion battery

Examples

Experimental program
Comparison scheme
Effect test

preparation example Construction

[0030] A preparation method of a polyimide composite fiber membrane is one of the preparation methods of the above-mentioned polyimide composite fiber membrane, and the preparation method of the polyimide composite fiber membrane comprises the following steps:

[0031] Step S100: dissolving the low-melting polymer in an organic solvent to obtain a filling solution of the low-melting polymer.

[0032] Further, the melting point of the low melting point polymer is 100°C to 160°C. Specifically, the low-melting point polymer is selected from low-density polyethylene (LDPE), high-density polyethylene (HDPE), polymethyl methacrylate (PMMA), polyethylene oxide (PEO), polyethylene succinate At least one of alcohol esters (PES).

[0033] Specifically, the organic solvent is selected from one of toluene, xylene, acetone, chloroform, glacial acetic acid, and tetrahydrofuran. The organic solvent is capable of dissolving the low-melting polymer into a homogeneous polymer solution.

[00...

Embodiment 1

[0056] The preparation steps of the polyimide composite fiber membrane of the present embodiment are as follows:

[0057] (1) Preparation of polyimide fiber base film:

[0058] At room temperature, 10 g of polyamic acid, a precursor of polyimide, was weighed, then added to 100 mL of N,N-dimethylacetamide, and mechanically stirred for 6 hours to obtain a uniform and viscous polyamic acid spinning solution. The spinning solution was prepared into a polyamic acid fiber membrane by using an electrospinning apparatus, and the spinning conditions were: voltage 20kV, ambient temperature 25°C; ambient humidity 40%; receiving distance 20cm. The polyamic acid fiber membrane is then subjected to thermal imidization treatment, and heat-treated at 100° C., 200° C., and 300° C. for 1 hour respectively, to obtain a layer of polyimide fiber base membrane. Among them, the specifications of the polyimide fiber base membrane are: the thickness is 8±1 μm; the fiber diameter is 0.4±0.1 μm, and th...

Embodiment 2

[0064] The preparation steps of the polyimide composite fiber membrane of the present embodiment are as follows:

[0065] (1) Preparation of polyimide fiber base film:

[0066] At room temperature, 16 g of polyamic acid, a precursor of polyimide, was weighed, and then added to 100 mL of N,N-dimethylacetamide, and mechanically stirred for 6 hours to obtain a uniform and viscous polyamic acid spinning solution. The spinning solution was prepared into a polyamic acid fiber membrane by using an electrospinning apparatus, and the spinning conditions were as follows: voltage 25kV, ambient temperature 20°C; ambient humidity 45%; receiving distance 16cm. The polyamic acid fiber membrane is then thermally imidized, and heat-treated at 100°C, 200°C, and 300°C for 1 hour, respectively, to obtain a layer of polyimide fiber base film. Among them, the specifications of the polyimide fiber base membrane are: the thickness is 12±1 μm; the fiber diameter is 0.7±0.1 μm, and the pore diameter i...

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
Melting pointaaaaaaaaaa
Thicknessaaaaaaaaaa
Fiber diameteraaaaaaaaaa
Login to view more

Abstract

The invention relates to a polyimide composite fiber membrane, a preparation method thereof and a lithium ion battery, and belongs to the technical field of batteries. The polyimide composite fiber membrane comprises a polyimide fiber base membrane and a low-melting-point polymer embedded in internal pores of the polyimide fiber base membrane, wherein the low-melting-point polymer has a microporous structure. The low-melting-point polymer of the polyimide composite fiber membrane has the microporous structure, so that the polyimide composite fiber membrane has a thermal closing function; and when the temperature of the polyimide composite fiber membrane rises to the melting temperature of the low-melting-point polymer, the low-melting-point polymer can be automatically melted to fill the microporous structure of the fiber membrane, so that the porous membrane is converted into a compact membrane to increase the air permeability value of the polyimide composite fiber membrane, the internal resistance of the polyimide composite fiber membrane is further increased, the charging and discharging current of the battery is reduced, and the safety problem caused by continuous charging and discharging of the battery in a high-temperature environment is avoided.

Description

technical field [0001] The invention relates to the technical field of batteries, in particular to a polyimide composite fiber membrane, a preparation method thereof and a lithium ion battery. Background technique [0002] Lithium-ion batteries have the advantages of low self-discharge rate, long cycle life and good safety. They are currently one of the most widely used energy storage technologies and are widely used in mobile phones, notebook computers and digital cameras. Especially in recent years, people have begun to use lithium-ion batteries with high energy density as the power source of automobiles to alleviate energy shortage and environmental pollution problems. Generally speaking, lithium-ion batteries are mainly composed of four parts: positive electrode, negative electrode, electrolyte and separator. The separator is an insulating film material with many micropores inside. In the battery, physical isolation is used to avoid short circuit caused by contact betwe...

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): D06M15/227D01F6/74D04H1/728D04H1/4326H01M10/0525D06M101/30
CPCD06M15/227D01F6/74D04H1/728D04H1/4326H01M10/0525D06M2101/30Y02E60/10
Inventor 李艳玲程忠林峰李娟娟
Owner SUNWODA ELECTRIC VEHICLE BATTERY 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