Preparation method of high-density lithium iron phosphate cathode material

A technology of lithium iron phosphate and positive electrode materials, which is applied in the field of preparation of high-density lithium iron phosphate positive electrode materials, can solve the problems of insufficient drying of precursors, poor performance of lithium iron phosphate, and low solid content of slurry, and achieve excellent electrochemical performance. performance, promotion of uniform distribution, effect of low liquid content

Active Publication Date: 2020-04-07
江西省金锂科技股份有限公司
View PDF5 Cites 1 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

[0005] The purpose of the present invention is to provide a method for preparing a high-density lithium iron phosphate cathode material with excellent performance, which can effectively solve the problem of poor performance of the lithium iron phosphate prepared in the prior art, low solid content of the slurry and poor drying of the precursor during the preparation process. Sufficient, technical problems of high preparation cost and large pollution

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 high-density lithium iron phosphate cathode material
  • Preparation method of high-density lithium iron phosphate cathode material
  • Preparation method of high-density lithium iron phosphate cathode material

Examples

Experimental program
Comparison scheme
Effect test

preparation example Construction

[0029] The invention provides a method for preparing a high-density lithium iron phosphate cathode material, the method comprising the following steps:

[0030] A. Mechanical activation: add a certain amount of deionized water to the ball milling equipment, and then add lithium source, composite iron source, phosphorus source, carbon source and surfactant in proportion, wherein, Li: Fe: P molar ratio is (1 ~1.2): (0.96 ~ 1.2): 1, the carbon source weight is 8-12wt% of the theoretical production amount of lithium iron phosphate, and the weight of the surfactant is 8-20wt% of the lithium source addition; the composite iron source is It is obtained by mixing reducing iron powder with a D50 of 1-2 μm and ferric orthophosphate with a primary particle size of 50-200 nm in a molar ratio of 1:10-1:1 (preferably 1:5-1:1), and high-speed ball milling for 4-200 nm. After 8 hours, a mixed slurry is formed, and the solid content of the slurry is 52% to 68%;

[0031] B, solid-liquid separa...

Embodiment 1

[0037] Ferric orthophosphate (FePO) with a primary particle size of 50 nm 4 ) 300.00 kg and 11.14 kg of metal iron powder with a particle size D50 of 2um are mixed to obtain a composite iron source, and 400 kg of deionized water is added to the ball mill, and then 73.52 kg of lithium carbonate, composite iron source, 20.68 kg of lithium dihydrogen phosphate, hard 41.47 kilograms of fatty acid, 18.84 kilograms of surfactant cetyltrimethylammonium bromide are placed in the ball mill, carry out ball milling and make slurry, the ball milling time is 4 hours, and the slurry particle size controls 1.5 microns, obtains that solid content is 65 % homogeneous mixed slurry. Then the ball mill slurry is pumped into a diaphragm filter press with a diaphragm pump for pressure filtration, and the filtration time is 1.5 hours to obtain a precursor with a moisture content of 15% or less; then the precursor is transported into a flash dryer for further Drying and mixing, the drying inlet temp...

Embodiment 2

[0041] Ferric orthophosphate (FePO) with a primary particle size of 100 nm 4 ) 150.00 kilograms and 11.14 kilograms of metal iron powders of 1um with a particle diameter D50 mix to obtain a composite iron source, add 250 kilograms of deionized water in the ball mill, then lithium carbonate 44.33 kilograms, composite iron source, 15.78 kilograms of stearic acid, sixteen 6.65 kg of alkyltrimethylammonium bromide was placed in a ball mill, and ball milled to make a slurry. The ball milling time was 6 hours, and the slurry particle size was controlled at 1.0 micron to obtain a homogeneous mixed slurry with a solid content of 60%. Then the ball mill slurry is pumped into a diaphragm filter press with a diaphragm pump for press filtration, and the filter press time is 2.0 hours to obtain a precursor with a liquid content of 12%; then the precursor is transported into a flash dryer for further Drying and mixing, the drying inlet temperature is 150°C, and the outlet temperature is 70°...

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
particle diameteraaaaaaaaaa
densityaaaaaaaaaa
densityaaaaaaaaaa
Login to view more

Abstract

The invention provides a preparation method of a high-density lithium iron phosphate cathode material, comprising the main steps: mixing reducing iron powder and ferric phosphate according to a certain ratio to obtain a composite iron source; adding deionized water into a ball milling apparatus, adding a lithium source, the composite iron source, a phosphorous source, a carbon source and a surfactant, and performing ball milling to obtain a slurry; injecting the slurry into a diaphragm press filter to carry out solid-liquid separation to obtain a precursor having a solid content of about 85%;drying the precursor in a flash dryer to obtain precursor powder having a liquid content of less than 1%; sintering the precursor powder in a kiln with a protective atmosphere, cooling, and performingjet crushing to obtain lithium iron phosphate powder. The preparation method has the advantages that the method is simple, the cost is low and the finished material has good electrochemical properties.

Description

technical field [0001] The invention belongs to the field of green energy materials, in particular to the technical field of lithium batteries, and in particular to a preparation method of a high-density lithium iron phosphate cathode material. Background technique [0002] Lithium-ion batteries have the advantages of high specific energy, high working voltage, low self-discharge rate, long cycle life, and no pollution, and have become a hot spot in the development of power batteries. As an important part of lithium-ion batteries, cathode materials are the key factors that determine the safety, capacity and price of batteries. At present, the anode materials for industrialized power lithium-ion batteries are mainly lithium iron phosphate and high-nickel ternary materials, among which lithium iron phosphate materials are in great demand. [0003] The high-temperature solid-phase method is used to produce lithium iron phosphate. At present, the general process route in the in...

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 Patents(China)
IPC IPC(8): C01B25/45H01M4/58H01M10/0525
CPCC01B25/45C01P2004/03C01P2004/61C01P2006/10C01P2006/11C01P2006/12C01P2006/40C01P2006/80H01M4/5825H01M10/0525H01M2004/028Y02E60/10
Inventor 谢香兰杨安臣肖水龙熊杜娟罗邵滨
Owner 江西省金锂科技股份有限公司
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