Electrolyte resistant wrinkle lithium ion battery diaphragm preparation method and prepared diaphragm

A lithium ion battery and electrolyte technology, which is applied in the preparation of anti-electrolyte wrinkle lithium ion battery separators, and the field of anti-electrolyte wrinkle lithium ion battery separators, can solve the problems of complexity and great influence on battery performance, etc.

Active Publication Date: 2019-05-03
深圳市博盛新材料有限公司
View PDF3 Cites 5 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

However, the improvement of the viscosity of the electrolyte involves changing various components of the electrolyte, and various components have a great influence on the performance of the battery, which is very complicated.

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
  • Electrolyte resistant wrinkle lithium ion battery diaphragm preparation method and prepared diaphragm
  • Electrolyte resistant wrinkle lithium ion battery diaphragm preparation method and prepared diaphragm
  • Electrolyte resistant wrinkle lithium ion battery diaphragm preparation method and prepared diaphragm

Examples

Experimental program
Comparison scheme
Effect test

Embodiment 1

[0066] (1) Raw material preparation: the polypropylene raw material with a melt index of 0.8 g / 10 min, an isotacticity of 98%, and a number average molecular weight of 420,000 was used.

[0067] (2) Diaphragm preparation: the polypropylene raw material is melt-extruded by using a single-screw extruder with an aspect ratio L / D≥34, and the extrusion temperature is 230°C. The melt is coarsely filtered, precisely metered, and finely filtered, and then cast into a film through a forming die with an opening of 2mm, and cooled to 80°C by a casting roll with a diameter of 700mm to form a cast film with high crystallinity and orientation. Thin film diaphragm. The diaphragm is further wound after traction, on-line thickness measurement, surface defect treatment, edge trimming. The thickness of the diaphragm is 10-15 microns, and the thickness uniformity is ±0.1 microns. The extrusion screw is preferably a separating screw, which can separate the fully plasticized or not melt, transpor...

Embodiment 2

[0074] This embodiment adopts the polypropylene raw material that melt index is 1.0g / 10min, isotacticity is 98.5%, and number average molecular weight is 440000, and adopts the same technological step as embodiment 1, and wherein cold drawing temperature is 80 ℃, cold drawing The magnification is 1.03, the heat drawing temperature is 135°C, the heat drawing magnification is 3, and the heat setting shrinkage rate is 5%. After testing and calculation, the 5% strain stress, average pore size and porosity of the obtained lithium-ion battery separator are 520kgf / cm 2 , 41nm and 47.5%. The obtained lithium-ion battery separator was used to make a square battery, and the battery was disassembled and observed after liquid injection and formation, and the separator was flat and wrinkle-free.

Embodiment 3

[0076] This embodiment adopts the polypropylene raw material that melt index is 1.2g / 10min, isotacticity is 99%, and number average molecular weight is 410000, and adopts the same process step as embodiment 1, and wherein cold drawing temperature is 100 ℃, cold drawing The magnification is 1.07, the heat drawing temperature is 145°C, the heat drawing magnification is 5, and the heat setting shrinkage rate is 10%. After testing and calculation, the 5% strain stress, average pore size and porosity of the obtained lithium-ion battery separator are 516kgf / cm 2 , 42nm and 48%. The obtained lithium-ion battery separator was used to make a square battery, and the battery was disassembled and observed after liquid injection and formation, and the separator was flat and wrinkle-free.

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
melt flow indexaaaaaaaaaa
melt flow indexaaaaaaaaaa
pore sizeaaaaaaaaaa
Login to view more

Abstract

The invention provides an electrolyte resistant wrinkle lithium ion battery diaphragm preparation method. The electrolyte resistant wrinkle lithium ion battery diaphragm preparation method comprises the following steps that polypropylene raw materials are provided; the polypropylene raw materials are melted and extruded, a piece is made into a diaphragm by casting, and cooling is performed to obtain a diaphragm piece; heat treatment is performed on the diaphragm piece to make the diaphragm piece be perfect in crystallization, and then the cooling is performed; the diaphragm piece is subjectedto cold stretching to form microdefects, and then hot- stretching pore broadening is performed; heat shaping is performed on the stretched diaphragm piece; and natural cooling annealing is performed on the diaphragm piece after the heat shaping to obtain a lithium ion battery diaphragm finished product. According to the electrolyte resistant wrinkle lithium ion battery diaphragm preparation method, the melt index of the polypropylene raw materials is 0.8-1.8 g/10min, the isotacticity is 98-99%, the number-average molar mass is 410000-480000, and in the stretching step, the cold stretching temperature is 80-100 DEG C, the cold stretching multiple ratio is 1.03-1.07, the hot stretching temperature is 135-145 DEG C, and the hot stretching multiple ratio is 3-5. The invention further providesan electrolyte resistant wrinkle lithium ion battery diaphragm obtained by the electrolyte resistant wrinkle lithium ion battery diaphragm preparation method.

Description

technical field [0001] The invention belongs to the field of lithium ion battery separators, and in particular relates to a preparation method of an anti-electrolyte wrinkle lithium ion battery separator and an anti-electrolyte wrinkle lithium ion battery separator prepared by the method. Background technique [0002] Lithium-ion battery separator is one of the four key main materials of lithium-ion battery (positive electrode material, negative electrode material, electrolyte, separator). The separator is placed between the positive and negative poles of the battery, which plays a role in isolating electrons in the battery and preventing the short circuit of the positive and negative electrodes. The performance of the core components has a certain impact on the internal resistance, capacity, cycle performance and safety performance of the battery. [0003] Today, lithium-ion batteries are widely used in electric vehicles, power tools, and energy storage. According to diff...

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 Applications(China)
IPC IPC(8): B29C48/025B29C48/09B29C71/02H01M2/14H01M2/16B29K23/00H01M50/403H01M50/406H01M50/417H01M50/494
CPCY02E60/10
Inventor 徐志远
Owner 深圳市博盛新材料有限公司
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