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

Novel composite diaphragm for lithium ion battery

An ion battery, composite lithium technology, applied in secondary batteries, battery pack components, circuits, etc., can solve problems such as difficulty in meeting safety requirements, easy precipitation of lithium dendrites, battery explosion, etc., to improve thermal stability performance , The effect of improving heat shrinkage performance and high porosity

Inactive Publication Date: 2017-05-24
NANJING UNIV OF AERONAUTICS & ASTRONAUTICS +1
View PDF3 Cites 0 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

With the rapid development of lithium-ion power battery technology and technology, pure polyolefin materials have been difficult to meet their safety requirements
During the high-current charging process, lithium dendrites are easily precipitated on the surface of the graphite cathode, which will cause a short circuit after piercing the diaphragm, and even a battery explosion in severe cases

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

[0020] HDPE, paraffin oil, KH550 crosslinking agent, ultra-fine glass fiber, ethanol, etc. are selected as raw materials. The preparation method has the following steps:

[0021] (1) Take one part of KH550 and add 4 parts of ethanol to make a solution;

[0022] (2) Take a glass fiber, take 0.5 part of the solution in (1) and spray it on the glass fiber, mix the glass fiber with the solution by grinding, and dry the mixed fiber in an oven at 90 degrees Celsius ;

[0023] (3) Take 0.1 part of dried glass fiber and add 1 part of mixed melt of HDPE and paraffin oil at 150 degrees Celsius, and stir and mix with a high-speed mixer;

[0024] (4) After the mixed slurry is passed through three processes of casting machine, extruder and widening machine, a film is obtained.

[0025] The physical properties of the prepared diaphragm are as follows: (1) Air permeability: ≤160s / 100cc; (2) Porosity: 30%-45%; (3) Tensile strength (MD): MD≥2230Kgf / Cm 2 ; (4) Tensile strength (TD): TD ≥ 198...

Embodiment 2

[0026] HDPP, paraffin oil, KH550 crosslinking agent, ultra-fine glass fiber, ethanol, etc. are selected as raw materials. The preparation method has the following steps:

[0027] (1) Take one part of KH550 and add 5 parts of ethanol to make a solution;

[0028] (2) Take a glass fiber, take 0.1 part of the solution in (1) and spray it on the glass fiber, mix the glass fiber with the solution by grinding, and dry the mixed fiber in an oven at 90 degrees Celsius ;

[0029] (3) Take 0.1 part of dried glass fiber and add 1 part of HDPP and paraffin oil mixed melt at 180 degrees Celsius, and stir and mix with a high-speed mixer;

[0030] (4) After the mixed slurry is passed through three processes of casting machine, extruder and widening machine, a film is obtained.

[0031] The physical properties of the prepared diaphragm are as follows: (1) Air permeability: ≤160s / 100cc; (2) Porosity: 30%-45%; (3) Tensile strength (MD): MD≥2300Kgf / Cm 2 ; (4) Tensile strength (TD): TD ≥ 2020Kg...

Embodiment 3

[0032] HDPE, paraffin oil, KH550 crosslinking agent, ultra-fine glass fiber, ethanol, etc. are selected as raw materials. The preparation method has the following steps:

[0033] (1) Take a portion of KH550 and add 3 portions of ethanol to make a solution;

[0034] (2) Take a glass fiber, take 0.08 parts of the solution in (1) and spray it on the glass fiber, mix the glass fiber with the solution by ball milling, and dry the mixed fiber in an oven at 100 degrees Celsius ;

[0035] (3) Take 0.2 parts of dried glass fiber and add 1 part of HDPE and paraffin oil mixed solution at 150 degrees Celsius, and stir and mix with a high-speed mixer;

[0036] (4) After the mixed slurry is passed through three processes of casting machine, extruder and widening machine, a film is obtained.

[0037] The physical properties of the prepared diaphragm are as follows: (1) Air permeability: ≤160s / 100cc; (2) Porosity: 30%-45%; (3) Tensile strength (MD): MD≥2320Kgf / Cm 2 ; (4) Tensile strength (...

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
diameteraaaaaaaaaa
thicknessaaaaaaaaaa
strengthaaaaaaaaaa
Login to View More

Abstract

The invention relates to a novel composite diaphragm for a lithium ion battery. The composite diaphragm is prepared by soaking ultrafine fiber glass in a solution containing a crosslinking agent, filtering and drying; adding the treated ultrafine fiber glass into a mixed solution of molten polyethylene or polypropylene and paraffin, violently stirring for dispersing, broadening by using an extruder, and uniaxially or biaxially stretching to obtain the composite diaphragm. The composite diaphragm can effectively improve the supporting strength of a PP battery diaphragm, a PE battery diaphragm and other battery diaphragms and greatly improves the heat shrinkage performance on the basis that the advantages of excellent insulation, chemical stability, high porosity and the like of PP, PE and other materials are maintained; compared with the diaphragm into which the fiber glass is not added, the composite diaphragm provided by the invention has significantly improved heat stability under the condition that the charge capacity and the discharge capacity are ensured.

Description

technical field [0001] The invention belongs to the field of lithium-ion battery diaphragms, and in particular relates to a novel composite lithium-ion battery diaphragm. Background technique [0002] At present, lithium-ion battery separator materials are mainly polyolefin compounds such as polyethylene and polypropylene, and their properties such as acid and alkali resistance and heat resistance can basically meet the safety requirements of consumer electronics batteries. With the rapid development of lithium-ion power battery technology and technology, pure polyolefin materials have been difficult to meet their safety requirements. During the high-current charging process, lithium dendrites are easily precipitated on the surface of the graphite cathode, which will cause a short circuit after piercing the diaphragm, and even a battery explosion in severe cases. Contents of the invention [0003] In order to solve the problem of battery safety, the present invention prop...

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): H01M2/14H01M2/16H01M10/0525
CPCH01M10/0525H01M50/403H01M50/431H01M50/44Y02E60/10
Inventor 黄现礼何建平王涛龚浩宋尚军白耀宗刘杲珺董浩宇
Owner NANJING UNIV OF AERONAUTICS & ASTRONAUTICS