Positive electrode and preparation method and application thereof

A positive electrode and positive active material technology, applied in the field of positive electrode and its preparation, can solve the problems of increased battery internal resistance, increased heat production, etc., and achieve the effect of reducing internal resistance, reducing heat production, and simple preparation methods

Pending Publication Date: 2020-09-01
SVOLT ENERGY TECHNOLOGY CO LTD
View PDF10 Cites 12 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

[0006] The purpose of the present invention is to solve the problems of increased battery internal resistance and increased heat generation when the conductivity of the ternary material decreases, and to provide a positive electrode and its preparation method and application

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 electrode and preparation method and application thereof
  • Positive electrode and preparation method and application thereof

Examples

Experimental program
Comparison scheme
Effect test

preparation example Construction

[0037] The second aspect of the present invention provides a method for preparing a positive electrode as described above, wherein the method includes the following steps:

[0038] (1) The positive electrode active material, the first conductive agent, the optional second conductive agent and the binder are according to the weight of (85-97):(0.5-5):(0-5):(1-5) Mix evenly in the nitrogen methyl pyrrolidone solvent to prepare at least two coating slurries containing different total conductive agent contents;

[0039] (2) Mix the first conductive agent, the optional second conductive agent and the binder in the nitrogen methyl pyrrolidone solvent according to the weight ratio of (10-95):(0-70):(3-15) , prepared into a conductive layer slurry;

[0040] (3) Alternately coating the coating slurry and the conductive layer slurry on both sides of the current collector, then drying and hot rolling to obtain the positive electrode;

[0041] Wherein, along the direction away from the cu...

Embodiment 1

[0061] (1) Li(Ni 0.65 mn 0.35 )O 2 , conductive carbon black, carbon nanotubes and polyvinylidene fluoride are uniformly mixed in nitrogen methyl pyrrolidone solvent according to the weight ratio of 90:2.5:2.5:5 to obtain coating slurry 1, wherein, in coating slurry 1 , Li(Ni 0.65 mn 0.35 )O 2 , the weight ratio of the total weight of conductive carbon black, carbon nanotubes and polyvinylidene fluoride to nitrogen methyl pyrrolidone solvent is 1:0.65;

[0062] (2) Li(Ni 0.65 mn 0.35 )O 2 , conductive carbon black, carbon nanotubes and polyvinylidene fluoride are uniformly mixed in nitrogen methyl pyrrolidone solvent according to the weight ratio of 92:2.5:2:3.5 to obtain coating slurry 2, wherein, in coating slurry 2 , Li(Ni 0.65 mn 0.35 )O 2 , the weight ratio of the total weight of conductive carbon black, carbon nanotubes and polyvinylidene fluoride to nitrogen methylpyrrolidone (NMP) solvent is 1:0.65;

[0063] (3) Conductive carbon black, carbon nanotubes and...

Embodiment 2

[0070] (1) Li(Ni 0.7 mn 0.3 )O 2 , conductive carbon black, carbon nanotubes and polyvinylidene fluoride are uniformly mixed in nitrogen methyl pyrrolidone solvent according to the weight ratio of 95.5:1.5:1.2:1.8 to obtain coating slurry 1, wherein, in coating slurry 1 , Li(Ni 0.7 mn 0.3 )O 2 , the weight ratio of the total weight of conductive carbon black, carbon nanotubes and polyvinylidene fluoride to nitrogen methyl pyrrolidone solvent is 1:0.35;

[0071] (2) Li(Ni 0.7 mn 0.3 )O 2 , conductive carbon black, carbon nanotubes and polyvinylidene fluoride are uniformly mixed in nitrogen methyl pyrrolidone solvent according to the weight ratio of 96.5:1.3:1:1.2 to obtain coating slurry 2, wherein, in coating slurry 2 , Li(Ni 0.7 mn 0.3 )O 2 , the weight ratio of the total weight of conductive carbon black, carbon nanotubes and polyvinylidene fluoride to nitrogen methylpyrrolidone (NMP) solvent is 1:0.35;

[0072] (3) Conductive carbon black, carbon nanotubes and p...

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
densityaaaaaaaaaa
thicknessaaaaaaaaaa
Login to view more

Abstract

The invention relates to the technical field of power lithium ion battery cathode materials, and discloses a positive electrode and a preparation method and application thereof. The positive electrodecomprises a current collector, at least two layers of coatings and conductive layers, wherein the two sides of the current collector are sequentially coated with the coatings respectively, and the conductive layers are arranged between the adjacent coatings. Each coating contains a positive electrode active material, a first conductive agent, an optional second conductive agent and a binder, andthe weight ratio of the positive electrode active material to the first conductive agent to the second conductive agent to the binder is (85-97):(0.5-5):(0-5):(1-5); in the direction away from the current collector, in the adjacent coatings, the total content of the first conductive agent and the second conductive agent is sequentially decreased progressively, and the decreasing amount is not smaller than 10% of the total amount of the conductive agents; or the compaction densities of the adjacent coatings are sequentially decreased progressively, and the decreasing amount is not smaller than2%. The positive electrode can improve the bonding force and conductivity between coatings, can improve the electron transmission efficiency, can reduce the internal resistance of the electrode and the battery, can reduce the heat production of the battery and can further reduce the cost of the battery.

Description

technical field [0001] The invention relates to the technical field of positive electrode materials for power lithium-ion batteries, in particular to a positive electrode and a preparation method and application thereof. Background technique [0002] The positive electrode material systems of power batteries mainly include ternary systems, lithium manganese oxide systems and lithium iron phosphate systems. Among them, the ternary system has higher energy density, so it is most widely used in power batteries. However, in the power battery of the ternary system, the cost of the positive electrode material accounts for 30%-45% of the total cost of the battery, which is much higher than that of the lithium manganese oxide system and the lithium iron phosphate system. One of the important reasons is the cobalt resource in the ternary system scarcity. If the content of cobalt can be reduced in the ternary system or cobalt-free materials can be used, it will play a positive role ...

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): H01M4/13H01M4/131H01M4/139H01M4/1391H01M4/04H01M10/0525
CPCH01M4/0404H01M4/13H01M4/131H01M4/139H01M4/1391H01M10/0525H01M2004/021H01M2004/028Y02E60/10
Inventor 马锐苏树发罗必圣张健余金飞阴济光王化东
Owner SVOLT 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

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