Lithium ion battery core and preparation method thereof, and lithium ion battery

A technology of lithium-ion batteries and batteries, which is applied in the manufacture of electrolyte batteries, secondary batteries, battery pack components, etc. It can solve problems such as poor bonding and diaphragm clogging, and achieve improved bonding and enhanced bonding effects Effect

Active Publication Date: 2018-08-10
DO FLUORIDE NEW ENERGY TECHNOLOGY CO LTD
View PDF13 Cites 17 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

[0006] The purpose of the present invention is to provide a method for preparing a lithium-ion battery cell, thereby solving the problem that the separator coated with a bonding substance is easily bonded weakly or the separator is blocked during use.

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
  • Lithium ion battery core and preparation method thereof, and lithium ion battery
  • Lithium ion battery core and preparation method thereof, and lithium ion battery
  • Lithium ion battery core and preparation method thereof, and lithium ion battery

Examples

Experimental program
Comparison scheme
Effect test

Embodiment 1

[0030] The lithium-ion battery cell of the present embodiment has a structural schematic diagram as Figure 1 ~ Figure 3 As shown, it includes a first thin cell unit 4 and a second thin cell unit 5 that are stacked in sequence. The first thin cell unit 4 includes a separator bag 1 with a positive electrode sheet 3 and a negative electrode sheet 2 stacked on top of each other. The number of bags 1 is 3, the number of negative electrode sheets is 2, the structure of the second thin cell unit 5 can refer to the first thin cell unit 4, the difference is that the number of diaphragm bags 1 is 2, and the number of negative electrode sheets 2 Quantity is 3 pcs. The membrane bag 1 is made of a membrane including a polyolefin film and polyvinylidene fluoride adhesive layers provided on both surfaces of the polyolefin film. The thickness of the polyolefin film was 20 μm, and the thickness of the polyvinylidene fluoride adhesive layer was 1 μm. The lithium-ion battery cell is specifica...

Embodiment 2

[0035] The preparation method of the lithium-ion battery cell of the present embodiment, such as Figure 1 ~ Figure 3 shown, including the following steps:

[0036] 1) Refer to Example 1 to make the first thin cell unit and the second thin cell unit. The hot pressing conditions of the first thin cell unit and the second thin cell unit are the same, both at 90°C and 0.2MPa Hold down for 20s;

[0037] 2) After the first thin cell unit and the second thin cell unit are stacked in sequence, they are kept at 90° C. and 0.3 MPa for 60 seconds to obtain the lithium-ion battery cell.

[0038] In step 1), the diaphragm used in the diaphragm bag includes a polyolefin film and polyvinylidene fluoride adhesive layers arranged on both sides of the polyolefin film. The thickness of the polyolefin film was 20 μm, and the thickness of the polyvinylidene fluoride adhesive layer was 2 μm.

Embodiment 3

[0040] The preparation method of the lithium-ion battery cell of the present embodiment, such as Figure 1 ~ Figure 3 shown, including the following steps:

[0041] 1) Refer to Example 1 to make the first thin cell unit and the second thin cell unit, the hot pressing conditions of the first thin cell unit and the second thin cell unit are the same, both at 85°C and 0.1MPa Hold down for 10s;

[0042]2) After stacking the first thin cell unit and the second thin cell unit in sequence, they are kept at 90° C. and 0.3 MPa for 20 seconds to obtain the lithium-ion battery cell.

[0043] In step 1), the diaphragm used in the diaphragm bag includes a polyolefin film, and one side surface of the polyolefin film is provided with a ceramic particle layer and a polymethyl methacrylate adhesive layer sequentially from the inside to the outside, and the other side surface is It is also coated with a polymethyl methacrylate adhesive layer. The thickness of the polyolefin film is 20 μm, th...

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 core and a preparation method thereof, and a lithium ion battery. The preparation method comprises: assembling a positive electrode sheet, a negative electrode sheet and a separation membrane, and carrying out hot pressing at least twice to prepare the battery core, wherein the separation membrane comprises a base membrane and a polymer bonding substance coated on the base membrane. According to the present invention, the lithium ion battery core is prepared through the multiple hot pressing, wherein the first hot pressing provides the pre-pressing effect so as to achieve the primary bonding of the separation membrane and the electrode sheet and expose the gap at the bonding interface position, and the second hot pressing provides the supplementing effect, such that the polymer bonding substance can fully fill the gap generated by the pre-pressing, and the bonding effect of the bonding interface can be enhanced; and with the at least two hot pressing, the bonding effect at the bonding interface can be improved in a targeted manner, and the clogging of the separation membrane due to the infiltrating of the molten polymer bonding substance into the pores of the separation membrane can be avoided.

Description

technical field [0001] The invention belongs to the field of lithium-ion battery preparation, and in particular relates to a lithium-ion battery cell, a preparation method thereof, and a lithium-ion battery. Background technique [0002] Lithium-ion batteries, as a clean new energy source, have been more and more widely used in mobile phones, power vehicles and other fields. Lithium-ion batteries generally include a packaging case and a battery cell contained in the packaging case. The battery cell includes a positive electrode sheet, a negative electrode sheet, and a separator spaced between the positive electrode sheet and the negative electrode sheet. The separator is an ion-conducting, electronically insulating porous membrane that acts as a separator between the positive and negative electrodes. [0003] At present, the separators used in conventional lithium-ion batteries are polypropylene porous membranes, polyethylene porous membranes or polypropylene / polyethylene / p...

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): H01M10/058H01M10/0525H01M2/16H01M50/411H01M50/431H01M50/449
CPCH01M10/0525H01M10/058H01M50/431H01M50/411H01M50/449Y02E60/10Y02P70/50
Inventor 赵红娟许飞李云峰赵永锋王攀马红涛刘兴丹高红艳朱林剑尼亚琼
Owner DO FLUORIDE NEW ENERGY TECHNOLOGY 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