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

A lithium-ion battery separator with high fusing temperature and preparation method thereof

A lithium ion battery and separator technology, which is applied to the high fusing temperature lithium ion battery separator and the field of its preparation, can solve the problems of poor compatibility, many additional equipment, and the structure of the composite membrane is not easy to maintain, and achieves stable performance and good compatibility. The effect of improving the safety of use

Inactive Publication Date: 2016-10-19
INST OF CHEM CHINESE ACAD OF SCI
View PDF6 Cites 0 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

However, since the PTFE-based film cannot be prepared by the commonly used extrusion processing method, the preparation process of the composite film is cumbersome and requires many additional equipment.
Moreover, PTFE has poor compatibility with other polymers, and the composite membrane structure is not easy to maintain.

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

Examples

Experimental program
Comparison scheme
Effect test

Embodiment 1

[0024] By twin-screw extruder 1 the ETFE (weight average molecular weight 2.5 * 10 of 10wt%) 6 ), the diisobutyl adipate of 90wt% is at 250 ℃, melt extrusion under the condition of 180rpm obtains ETFE film liquid A; By twin-screw extruder 2, the high-density polyethylene (weight-average molecular weight 2.5× 10 6 ), 70wt% diisobutyl adipate was melt-extruded at 200°C and 160rpm to obtain PE film solution B; the two solutions were symmetrically arranged in three layers of A / B / A in a T-shaped co-extrusion die The structure is co-extruded and casted into a film, which is drawn and formed on a cooling roll with a surface temperature of 25°C. The thickness ratio of the three layers is 1:1.5:1 to obtain the primary film. The initial film is biaxially stretched, and the stretching ratio is vertical x horizontal = 3 x 3 times. The film obtained after stretching is washed with methanol and dried. Then the film was heat-set at a setting temperature of 100° C. for 1 min to obtain a thr...

Embodiment 2

[0026] By twin-screw extruder 1 with 60wt% ETFE (weight-average molecular weight 2.0 * 10 5 ), the triethyl citrate of 40wt% is at 240 ℃, melt extrusion under the condition of 200rpm obtains ETFE membrane liquid A; By twin-screw extruder 2, the high-density polyethylene (weight-average molecular weight 9.0 * 10 6 ), 90wt% triethyl citrate was melt-extruded at 200°C and 150rpm to obtain PE film solution B. The two solutions were co-extruded and casted into a film in a T-shaped co-extrusion die with an A / B / A three-layer symmetrical structure, and drawn on a cooling roll with a surface temperature of 25°C. The thickness ratio of the three layers was 1. : 1.5: 1, the initial film was obtained. The initial film is biaxially stretched, and the stretching ratio is vertical x horizontal = 6 x 6 times. The film obtained after stretching is washed with petroleum ether and dried. Then the film was heat-set at a setting temperature of 85° C. for 5 minutes to obtain a three-layer composi...

Embodiment 3

[0028] By twin-screw extruder 1 the ETFE (weight-average molecular weight 3 * 10 of 15wt%) 6 ), 85wt% dibutyl phthalate is at 280 ℃, and melt extrusion under the condition of 200rpm obtains ETFE film liquid A; By twin-screw extruder 2, 50wt% high-density polyethylene (weight-average molecular weight 5.0 * 10 5 ), 50wt% dibutyl phthalate was melt-extruded at 220°C and 180rpm to obtain PE film solution B. The two solutions were co-extruded and casted into a film in a T-shaped co-extrusion die with an A / B / A three-layer symmetrical structure, and drawn on a cooling roll with a surface temperature of 25°C. The thickness ratio of the three layers was 1. : 1.5: 1, the initial film was obtained. The initial film is biaxially stretched, and the stretching ratio is vertical x horizontal = 10 x 10 times. The film obtained after stretching is washed with trichlorethylene and dried. Then the film was heat-set at a setting temperature of 110° C. for 3 minutes to obtain a three-layer compo...

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
temperatureaaaaaaaaaa
pore sizeaaaaaaaaaa
Login to View More

Abstract

The invention discloses a lithium-ion battery diaphragm with high fusing temperature and a preparation method thereof. The separator is composed of ethylene-tetrafluoroethylene copolymer (ETFE) microporous membrane and polyethylene (PE) microporous membrane. ETFE and PE are respectively made into separators by thermal phase separation method, and after A / B / A three-layer co-extrusion casting composite, after biaxial stretching, the diluent is extracted to make lithium-ion battery separators; among them, the A layer is ETFE microporous Membrane, B layer is PE microporous membrane. The lithium-ion battery diaphragm provided by the invention has high fusing temperature, high mechanical strength and low cell closure temperature, and can effectively improve the safety performance of the lithium-ion battery.

Description

technical field [0001] The invention relates to the research field of lithium-ion battery separators, in particular to a lithium-ion battery separator with a high fusing temperature and a preparation method thereof. Background technique [0002] Environmental pollution and energy crisis have attracted widespread attention from all over the world. The new energy industry, represented by the new energy automobile industry and the energy storage industry, has received full support from the governments of major countries and regions around the world. Among them, the lithium-ion battery is the core component of the new energy industry, and its importance is self-evident. [0003] Lithium-ion batteries are mainly composed of positive and negative electrode materials, electrolytes and separators. The separator is an important part of the lithium-ion battery. Its main functions are: 1. To isolate the positive and negative electrodes and prevent the electrons in the battery from pa...

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): H01M2/16H01M50/417H01M50/426H01M50/491H01M50/581
CPCH01M50/403H01M50/449H01M50/411Y02E60/10
Inventor 吴杰刘必前叶钢
Owner INST OF CHEM CHINESE ACAD OF SCI