Lithium-ion battery pole piece and preparation method thereof

A lithium ion battery and pole piece technology, which is applied in the field of lithium ion battery pole pieces with gradient porosity and its preparation, can solve the problems of poor pore-making effect and difficult penetration of pore-forming agents, and achieves good ion conduction rate, The effect of increased energy density and good hole-making effect

Active Publication Date: 2020-09-29
SHENZHEN XINYUREN TECH
View PDF7 Cites 15 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

However, in the pore-forming process, the pore-forming agent i

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 pole piece and preparation method thereof
  • Lithium-ion battery pole piece and preparation method thereof
  • Lithium-ion battery pole piece and preparation method thereof

Examples

Experimental program
Comparison scheme
Effect test

Example Embodiment

[0058] Example 1

[0059] See Figure 1-Figure 3 According to the present invention, a lithium ion battery pole piece with gradient porosity is prepared according to the following method:

[0060] (1) Mix NMC, conductive agent Super-P, polyvinylidene fluoride PVDF at a mass ratio of 9.4:0.3:0.3 to prepare a mixture, and then mix the mixture with N-methylpyrrolidone at a mass ratio of 2:1, Prepared into electrode slurry;

[0061] (2) Divide the above-mentioned electrode slurry into two parts, add uniform and fine ammonium carbonate powder as the pore-forming agent, adjust the stirring speed to fully mix and disperse. Among them, the pore-forming agent and the active material in the first slurry The mass ratio is 0.3:1, and the mass ratio of the pore former to the active material in the second slurry is 0.6:1.

[0062] (3) Apply the first electrode slurry to the aluminum foil side of the current collector. After drying, the pore former decomposes and escapes, and no other substances re...

Example Embodiment

[0064] Example 2

[0065] The present invention prepares a lithium ion battery pole piece with gradient porosity according to the following method:

[0066] (1) Mix LFP, conductive agent Super-P, polyvinylidene fluoride PVDF at a mass ratio of 9.6:0.2:0.2 to prepare a mixture, and then mix the mixture with N-methylpyrrolidone at a mass ratio of 2:1, Prepared into electrode slurry;

[0067] (2) Divide the electrode slurry into two parts, add uniform and fine ammonium bicarbonate powder as the pore former, adjust the stirring speed to fully mix and disperse, among which, the pore former and active material in the first slurry The mass ratio of pore former is 0.4:1, and the mass ratio of pore former to active material in the second slurry is 0.8:1.

[0068] (3) Apply the first electrode slurry to the aluminum foil side of the current collector. After drying, the pore former decomposes and escapes, and no other substances remain; use a smooth surface pressure roller to perform the first ...

Example Embodiment

[0070] Example 3

[0071] The present invention prepares a lithium ion battery pole piece with gradient porosity according to the following method:

[0072] (1) Mix graphite, conductive agent Super-P, and adhesive LA133 at a mass ratio of 8.6:0.7:0.7 to prepare a mixture, and then mix the mixture with water solvent at a mass ratio of 3:1 to prepare electrode slurry material;

[0073] (2) Divide the above-mentioned electrode slurry into three parts, add uniform and fine ammonium bicarbonate powder as the pore former, adjust the stirring speed to fully mix and disperse, among which, the pore former and active material in the first slurry The mass ratio of pore former to active material is 0.2:1, the mass ratio of pore former to active material in the second slurry is 0.4:1, and the mass ratio of pore former to active material in the third slurry is 0.7:1.

[0074] (3) Apply the first electrode slurry to the copper foil side of the current collector. After drying, the pore former decomp...

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
Coating surface densityaaaaaaaaaa
Thicknessaaaaaaaaaa
Login to view more

Abstract

The invention belongs to the technical field of lithium-ion batteries and particularly relates to a lithium-ion battery pole piece with gradient porosity and a preparation method thereof, and the preparation method comprises the following steps: (1) mixing powder pore-forming agents with different contents with an active material, a conductive agent and a polymer binder according to the number ofdesigned pole piece layers to obtain multiple parts of electrode slurry with different pore-forming agent contents; (2) coating a current collector with the electrode slurry with the lowest pore-forming agent content, drying, and carrying out primary rolling compaction by using a compression roller to obtain a first coating; (3) applying the electrode slurry on the surface of the first coating layer by layer according to the sequence of the pore-forming agent contents from low to high; (4) heating and drying a pole piece to decompose and escape the pore-forming agents, and forming a gradient pore channel in the coating; and (5) carrying out secondary rolling on the dried multi-layer structure pole piece by adopting an embossing roller with a continuous hemispherical convex point structure.Compared with the prior art, the method has the advantages that the pole piece with the gradient porosity is prepared, high energy density is obtained through rolling, meanwhile, good rate capabilityis achieved, and the utilization rate of the active material is increased.

Description

technical field [0001] The invention belongs to the technical field of lithium-ion batteries, and more specifically relates to a lithium-ion battery pole piece with gradient porosity and a preparation method thereof. Background technique [0002] The energy density and rate performance of lithium-ion batteries are the focus of research attention, and the two often cannot be considered at the same time. For high-capacity pole pieces, the coating thickness or rolling compaction density is large, and the energy density of the pole piece is increased. However, under high-current conditions, lithium ions in the battery electrolyte are in the current high tortuosity porous electrodes. Transmission has become the shortest link with the lowest efficiency in the entire kinetic process. With the increase of coating thickness or compaction density, and in the cold pressing process, the pressure on the active material gradually decreases from the surface of the coating to the bottom, a...

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): H01M4/04H01M4/139H01M4/13H01M10/0525
CPCH01M4/0404H01M4/0435H01M4/13H01M4/139H01M10/0525H01M2004/021Y02E60/10
Inventor 周华民宋岚杨志明张云陶波王云明周军黄志高
Owner SHENZHEN XINYUREN 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