Preparation method of lithium ion battery positive plate and lithium battery manufactured thereby

A technology for lithium ion batteries and positive electrode sheets, which is applied in electrode manufacturing, battery electrodes, secondary batteries, etc., can solve the problems of poor flexibility of the electrode sheets, uneven coating, and temperature rise, and achieve the effect of reducing easy fragmentation.

Active Publication Date: 2015-07-15
DONGGUAN CHUANGMING BATTERY TECH
View PDF6 Cites 7 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

[0003] 1. When the temperature is below 20°C and the humidity is below 25%, the traditional positive electrode is easy to be brittle; PVDF is a commonly used positive electrode slurry preparation material, and PVDF is very plastic at a temperature below 20°C, which makes the flexibility of the electrode change. Poor, making it easy to crisp
[0004] 2. The 18650 high-capacity battery (above 2.5Ah) made of traditional positive electrodes has a high rate discharge temperature rise, and the temperature rise can reach 8-10°C at 1C discharge; after PVDF is swollen and formed into a film, it forms a layer The denser polymer film is not conducive to the transmission of lithium ions in the positive electrode, the polarization of lithium ions increases during discharge, and the discharge temperature rises
[0005] 3. The traditional coating method is easy to cause uneven coating, and powder falling off the edge when the pole piece is cut, which will eventually increase the self-discharge of the battery and affect the consistency 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
  • Preparation method of lithium ion battery positive plate and lithium battery manufactured thereby
  • Preparation method of lithium ion battery positive plate and lithium battery manufactured thereby
  • Preparation method of lithium ion battery positive plate and lithium battery manufactured thereby

Examples

Experimental program
Comparison scheme
Effect test

preparation example Construction

[0031] A preparation method of lithium ion battery positive plate, it comprises the following steps:

[0032] Step 1, using nitrogen methylpyrrolidone NMP or amides as solvent, adding dry powder mixed with PVDF, PEO, PVP or mixed with PVDF, PEO, PEG, wherein the weight ratio of PVDF:PEO:PVP or PVDF:PEO:PEG 18.5:1:0.5 to 16:3.5:0.5; formulated as 4-8 wt% glue. Among them, the amides can be dimethylformamide, diethylacetamide or dimethylacetamide and the like. With NMP or amides as solvent, PVDF, PEO, PVP, PEG can be dissolved.

[0033] Step 2, mix the positive electrode active material and the conductive agent for 30 to 60 minutes, then add 1 / 3 of the glue and stir for 20 to 40 minutes, then add 1 / 3 of the glue and stir for 20 to 30 minutes, and finally put the remaining 1 / 3 of the glue solution was added and stirred for 10 to 20 minutes to prepare a positive electrode slurry with a solid content of 78 to 85%. Add the glue solution into the mixture of the positive electrode ...

Embodiment 1

[0039] Embodiment one, a kind of preparation method of lithium-ion battery, comprises the following steps:

[0040] S1. Add dry powder of PVDF, PEO, PVP (or PEG) with nitrogen methylpyrrolidone (NMP) or amides (such as: dimethylformamide, diethylacetamide, dimethylacetamide) solvent, Among them, the ratio of PVDF:PEO:PVP is 18.5:1:0.5; it is formulated into 4-8wt% glue.

[0041] S2. Mix the positive electrode active material and the conductive agent for 30-60 minutes, add 1 / 3 of the glue and stir for 20-40 minutes, add 1 / 3 of the glue and stir for 20-30 minutes, add the remaining 1 / 3 of the glue and stir for 10-20 minutes, Prepare a slurry with a solid content of 78-85%.

[0042] S3. Using the silk screen printing process, some of the mesh holes of the screen template will leak the positive and negative electrode slurry onto the surface of the aluminum foil and copper foil current collector respectively, and the rest of the mesh holes will be blocked and cannot pass through t...

Embodiment 2

[0044] Embodiment two, a kind of preparation method of lithium ion battery, comprises the following steps:

[0045]S1. Add dry powder of PVDF, PEO, PVP (or PEG) with nitrogen methylpyrrolidone (NMP) or amides (such as: dimethylformamide, diethylacetamide, dimethylacetamide) solvent, Among them, the ratio of PVDF:PEO:PVP is 16:3.5:0.5; it is formulated into 4-8wt% glue.

[0046] S2. Mix the positive electrode active material and the conductive agent for 30-60 minutes, add 1 / 3 of the glue and stir for 20-40 minutes, add 1 / 3 of the glue and stir for 20-30 minutes, add the remaining 1 / 3 of the glue and stir for 10-20 minutes, Prepare a slurry with a solid content of 78-85%.

[0047] S3. Using the silk screen printing process, some of the mesh holes of the screen template will leak the positive and negative electrode slurry onto the surface of the aluminum foil and copper foil current collector respectively, and the rest of the mesh holes will be blocked and cannot pass through 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

No PUM Login to view more

Abstract

The invention discloses a preparation method of a lithium ion battery positive plate. The method comprises the following steps: 1, adding dry powder containing polyoxyethylene PEO into a solvent to prepare a glue solution; 2, adding the glue solution into a mixture of a positive active material and a conductive agent and stirring to prepare positive paste; and 3, coating the positive paste by means of silk-screen printing coating and drying. According to the preparation method of the lithium ion battery positive plate and the lithium ion battery positive plate manufactured by using the preparation method, PEO softening positive paste is added to prevent the crisping of the positive plate; by using a silk-screen printing coating way, the phenomenon that powder falls down during slicing is avoided, and the performance of the lithium ion battery is greatly improved.

Description

technical field [0001] The invention relates to the technical field, in particular to a method for preparing a positive electrode sheet of a lithium ion battery and the prepared lithium ion battery. Background technique [0002] At present, the positive electrodes of lithium-ion batteries generally have the following disadvantages: [0003] 1. When the temperature is below 20°C and the humidity is below 25%, the traditional positive electrode is easy to be brittle; PVDF is a commonly used positive electrode slurry preparation material, and PVDF is very plastic at a temperature below 20°C, which makes the flexibility of the electrode change. Poor, making it easy to crisp. [0004] 2. The 18650 high-capacity battery (above 2.5Ah) made of traditional positive electrodes has a high rate discharge temperature rise, and the temperature rise can reach 8-10°C at 1C discharge; after PVDF is swollen and formed into a film, it forms a layer The denser polymer film is not conducive to...

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): H01M4/139H01M10/0525
CPCH01M4/0414H01M4/139H01M10/0525Y02E60/10
Inventor 赵悠曼程建良
Owner DONGGUAN CHUANGMING BATTERY TECH
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

Browse by: Latest US Patents, China's latest patents, Technical Efficacy Thesaurus, Application Domain, Technology Topic.

© 2024 PatSnap. All rights reserved.Legal|Privacy policy|Modern Slavery Act Transparency Statement|Sitemap