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

Positive pole piece and lithium ion battery comprising positive pole piece

A technology of positive electrode sheet and positive current collector, which is applied in the direction of positive electrode, battery electrode, secondary battery, etc., can solve the problems of poor battery safety performance, poor safety performance, and potential safety hazards, and achieve improved cycle performance and DCIR The effect of a large rate of change in growth

Active Publication Date: 2020-12-11
ZHUHAI COSMX BATTERY CO LTD
View PDF4 Cites 5 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

In recent years, the development of volume energy density and mass energy density of digital lithium-ion batteries has almost reached the limit of materials. Due to the poor safety performance of high-voltage lithium cobaltate (≥4.4V) and high-nickel materials, the safety performance of the corresponding batteries Performance deteriorates, and lithium-ion batteries use flammable organic solvents as electrolyte solvents, which poses safety hazards

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
  • Positive pole piece and lithium ion battery comprising positive pole piece
  • Positive pole piece and lithium ion battery comprising positive pole piece
  • Positive pole piece and lithium ion battery comprising positive pole piece

Examples

Experimental program
Comparison scheme
Effect test

Embodiment 1

[0057] (1) The positive electrode active material lithium iron phosphate (D 50 <3μm), the conductive agent SP and the binder 5130 glue are mixed at a weight ratio of 86%:4%:10%, and the mixture is dispersed in NMP, and the safety layer slurry is obtained after double planetary stirring. The safety layer slurry was coated on the front and back sides of an aluminum foil current collector with a thickness of 12 μm, dried after coating, and the thickness of the coating layer on one side was 5 μm, to obtain a positive electrode sheet containing a safety layer.

[0058] (2) Mix lithium aluminum titanium phosphate (LATP), PVDF, and carbon nanotubes in a weight ratio of 50%:20%:30%, disperse the mixture in NMP, and obtain a conductive layer slurry after double planetary stirring. The conductive layer slurry is coated on the surface of the positive electrode sheet containing the safety layer, and dried after coating. The thickness of the coating layer on one side is 2 μm, and the posit...

Embodiment 2

[0075] The preparation method of embodiment 2 is the same as embodiment 1, except that step (2):

[0076] (2) Mix lithium aluminum titanium phosphate (LATP), PVDF, and SP at a weight ratio of 55%:15%:30%, disperse the mixture in NMP, and obtain a conductive layer slurry after double-planetary stirring. The conductive layer slurry is coated on the surface of the positive electrode sheet containing the safety layer, and dried after coating. The thickness of the coating layer on one side is 2 μm, and the positive electrode sheet containing the conductive layer and the safety layer is obtained.

Embodiment 3-9

[0094] The preparation method of Examples 3-9 is the same as that of Example 1, except that the selection and additives of the second conductive agent, the second binder, and the ion-conducting compound in step (2) are different, as shown in Table 2.1.

[0095] Table 2.1 Composition of the positive pole pieces of Examples 1, 3-9 and Comparative Examples 1, 4

[0096]

[0097] Table 2.2 Lithium-ion battery performance test results of Examples 1, 3-9 and Comparative Examples 1, 4

[0098] Experimental group 400 cycles capacity retention (%) 400 cycle internal resistance change rate (%) Acupuncture test Heavy Object Impact Test Example 1 89.31％ 51.3％ 10 / 10 pass 9 / 10 pass Comparative example 4 90.28％ 48.5％ 9 / 10 pass 8 / 10 pass Example 3 88.79％ 49.4％ 10 / 10 pass 10 / 10 pass Example 4 90.31％ 45.3％ 10 / 10 pass 10 / 10 pass Example 5 89.27％ 43.1％ 10 / 10 pass 10 / 10 pass Example 6 91.45％ 41.2％ 10 / 10 pass 9 / 10...

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 provides a lithium ion battery positive pole piece and a preparation method thereof. The positive pole piece comprises a positive current collector layer, a safety layer, a conductive layer and an active substance layer, and the conductive layer comprises a conductive ion compound, a second conductive agent and a second binder. Compared with a conventional pole piece with a two-layercoating structure, the novel multi-layer coating pole piece has higher safety and more excellent cycle performance by using the novel multi-layer coating pole piece structure design; and a multi-layer coating technology is used, and the interface problem caused by poor electronic conductivity and ionic conductivity of the safety layer and the active substance layer in the positive pole piece in the circulation process can be improved by utilizing the high conductivity and the ionic conductivity of the conductive layer, so the safety of the high-energy-density lithium ion battery is ensured, and meanwhile, the cycle performance of the lithium ion battery and the problem of large DCIR growth change rate in the cycle process can be further improved.

Description

technical field [0001] The invention belongs to the technical field of lithium ion batteries, and in particular relates to a positive pole piece and a lithium ion battery including the positive pole piece. Background technique [0002] Power batteries and high-voltage digital batteries are currently developing rapidly, and are widely used in 3C consumer digital fields such as mobile phones, notebook computers, tablet computers, and small Bluetooth batteries and electric vehicles. Whether it is digital or power fields, the requirements for the safety performance of lithium-ion batteries are getting higher and higher. In recent years, the development of volume energy density and mass energy density of digital lithium-ion batteries has almost reached the limit of materials. Due to the poor safety performance of high-voltage lithium cobaltate (≥4.4V) and high-nickel materials, the safety performance of the corresponding batteries Performance deteriorates, and lithium-ion batter...

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): H01M4/131H01M4/36H01M4/48H01M4/58H01M10/0525H01M4/02H01M4/62
CPCH01M4/131H01M4/366H01M4/48H01M4/58H01M10/0525H01M4/62H01M2004/028Y02E60/10
Inventor 曾家江樊亚楠伍鹏李素丽
Owner ZHUHAI COSMX BATTERY CO LTD