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

Tangent plane coated lithium ion battery positive plate and preparation method thereof

A lithium-ion battery, battery cathode technology, applied in battery electrodes, non-aqueous electrolyte battery electrodes, secondary batteries, etc., can solve the problems of lowering the qualification of the manufacturing process, lowering the production qualification rate, battery safety problems, etc., to reduce burrs, Low cost and good effect

Inactive Publication Date: 2020-05-19
ГУАНДУН ГУАНШЭНЬ ИНВАЙРОНМЕНТАЛ ПРОТЕКШН ТЕКНОЛОДЖИ КО ЛТД
View PDF6 Cites 0 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

The shape of the positive electrode, the separator and the negative electrode is generally a rectangular sheet, and the widths between them are generally designed to be different. The middle separator is the widest and fully isolates the positive electrode and the negative electrode. The width of the positive electrode is the smallest, and the width ratio of the negative electrode is The width of the positive electrode is slightly larger. This is because during the charging process of lithium-ion batteries, lithium ions migrate from the positive electrode to the negative electrode. The negative electrode corresponding to the vertical square must have enough material for lithium ions to intercalate, otherwise lithium ions will be reduced to form metals. Simple substance, commonly known as "lithium analysis", lithium analysis can lead to internal short circuit of the battery, causing safety problems in battery use
[0005] Designing that the width of the positive electrode is smaller than that of the negative electrode can solve the problem of "lithium separation", but at the same time it also creates a new problem, that is: the edge of the positive electrode is produced by cutting equipment, because the cutting process is affected by the performance of the equipment and the operating process The edge of the positive electrode is not completely flat. This unevenness leads to two defects of the pole piece: the first is the existence of "burrs". Reduced, and more seriously, those "burrs" hidden dangers that have not been effectively detected during the manufacturing process may be stimulated by certain effects such as vibration to form an internal short circuit during subsequent use, causing safety problems such as swelling, heating, and fire; The second is that the electrode material falls off and forms conductive dust. This falling dust can form a micro-short circuit point inside the battery, resulting in a lower qualification of the manufacturing process, and may also form an internal short circuit of the battery.

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
  • Tangent plane coated lithium ion battery positive plate and preparation method thereof
  • Tangent plane coated lithium ion battery positive plate and preparation method thereof

Examples

Experimental program
Comparison scheme
Effect test

Embodiment 1

[0035] 1. Materials used: INR18650-2000mAh lithium-ion battery positive plate and polyurethane spray (produced by Kejian Polymer Materials (Shanghai) Co., Ltd., brand KJ-1807) mass-produced by the factory.

[0036] 2. Equipment used: Fixtures for spraying (such as figure 1 ), adjustable constant temperature air duct (Foshan Yaojiang Electronics Co., Ltd., 8018 model), retracting and unwinding roller seat frame.

[0037] 3. Coating process of sectioned polyurethane:

[0038] 3.1 Hang the rolled battery positive electrode on two roller mounts with a distance of 2 meters;

[0039] 3.2 Install the nozzles of the two-pack polyurethane spray container and the spraying fixture in the middle of the roller mount and vertically align them with the cutting surfaces on both sides of the positive electrode sheet;

[0040] 3.3 Install two sets of adjustable constant temperature air cylinders in the middle of the polyurethane nozzle and the rewinding roller frame, and make the middle of th...

Embodiment 2

[0052] (1) Carry out group marking in a batch of 50,000 positive electrode sheets of the model INR18650-2000mAh in normal mass production, with 10,000 pieces in each group, and the groups are marked as A, B, C, D and E respectively.

[0053] (2) Take group B pole pieces and coat them with a polyurethane coating with a thickness of 20±10 μm, and then make 10,000 pole group structures together with negative pole pieces and separators.

[0054] (3) Use a DC resistance tester to detect the number S1 of the short circuit (the resistance between the positive and negative electrodes of the pole group is less than 200 megohms).

[0055] (4) Analyze the medium caused by the short circuit, the quantity caused by burrs is Sa1, the quantity caused by dust is Sb1, and the quantity caused by other factors is Sc1.

[0056] (5) Record the values ​​of S1, Sa1, Sb1 and Sc1 respectively; the results are shown in Table 1: S1=25, Sa1=4, Sb1=11, Sc1=10.

[0057] Compared with Comparative Example 1...

Embodiment 3

[0059] (1) Carry out group marking in a batch of 50,000 positive electrode sheets of the model INR18650-2000mAh in normal mass production, with 10,000 pieces in each group, and the groups are marked as A, B, C, D and E respectively.

[0060] (2) Take group C pole pieces and coat them with a polyurethane coating with a thickness of 50±10 μm, and then make 10,000 pole group structures together with negative pole pieces and separators.

[0061] (3) Use a DC resistance tester to detect the number S2 of short circuit (resistance between the positive and negative electrodes of the pole group is less than 200 megohms).

[0062] (4) Analyze the medium caused by the short circuit, the quantity caused by burrs is Sa2, the quantity caused by dust is Sb2, and the quantity caused by other factors is Sc2.

[0063] (5) Record the values ​​of S2, Sa2, Sb2 and Sc2 respectively; the results are shown in Table 1: S2=15, Sa2=1, Sb2=6, Sc2=8.

[0064] Compared with Example 2, the total number of ...

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
Thicknessaaaaaaaaaa
Thicknessaaaaaaaaaa
Thicknessaaaaaaaaaa
Login to View More

Abstract

The invention relates to a lithium ion battery positive plate, at least one side section of the lithium ion battery positive plate is coated with a polyurethane coating, and the thickness of the polyurethane coating is 90-210 microns. The polyurethane is sprayed on the tangent plane of the battery positive plate, so that the burr problem of the tangent plane of the positive plate is greatly reduced, and meanwhile, the powder falling problem of the tangent plane is reduced through the cohesiveness of the polyurethane, so that the percent of pass of the production and manufacturing process is improved, and the safety performance of the lithium ion battery is improved.

Description

technical field [0001] The invention belongs to the technical field of chemical power supply—lithium ion battery, and in particular relates to a cut surface-coated lithium ion battery positive electrode sheet and a preparation method thereof. Background technique [0002] Since lithium-ion batteries were commercialized in 1991, they have been rapidly and widely used in many fields, including military industry, aerospace, industrial production and civilian use, due to their high energy density, long cycle life, and high comprehensive performance such as environmental protection. And so on, the application also includes the power supply of high rate performance and the energy storage of lower rate performance. In recent years, with the further strengthening of domestic and international social demands for new energy vehicles and energy-saving and environmental protection concepts, the application of lithium-ion batteries has been further developed in the field of vehicles. ...

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): H01M4/13H01M4/139H01M4/36H01M4/62H01M10/0525
CPCH01M4/13H01M4/139H01M4/366H01M4/622H01M10/0525Y02E60/10
Inventor 庄文生温尚龙陈欣义
Owner ГУАНДУН ГУАНШЭНЬ ИНВАЙРОНМЕНТАЛ ПРОТЕКШН ТЕКНОЛОДЖИ КО ЛТД