Hydrothermal synthesis method for lithium ion-cell anode material of ferric phosphate lithium

A technology of lithium ion battery and hydrothermal synthesis method, which is applied in the field of phosphate, can solve the problems of poor electrochemical performance, impure phase, and uneven particle size, and achieve improved electronic conductivity, good batch stability, and particle size The effect of uniform diameter distribution

Inactive Publication Date: 2008-02-06
HEBEI LITAO BATTERY MATERIAL
View PDF7 Cites 81 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

The method adopts feeding process parameter control and surfactant technology to effectively control LiFePO 4 The particle size and chemical composition of the product overcome the shortcomings of poor electrochemical performance, uneven particle size, impure phase, large equipment investment and complicated process.

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
  • Hydrothermal synthesis method for lithium ion-cell anode material of ferric phosphate lithium

Examples

Experimental program
Comparison scheme
Effect test

Embodiment 1

[0032] The first step, hydrothermal synthesis reaction

[0033] 973g or 3.5mol of FeSO 4 ·7H 2 O was dissolved in water and diluted to 3.5L. After standing for 12 hours, filtered to remove a small amount of precipitate; 408g of 85% phosphoric acid containing 3.5mol of pure phosphoric acid was dissolved in water and diluted to 0.5L; 442g That is, 10.5mol of LiOH·H 2 O was dissolved in water and diluted to 3L.

[0034]Add the above-mentioned phosphoric acid solution and lithium hydroxide solution into a 10L autoclave, then add 2g of cationic surfactant cetyltrimethylammonium bromide and 0.5g of nonionic surfactant octylphenol polyoxyethylene ether, and use an inert After the air in the dead volume in the autoclave is purged by gas, the autoclave is sealed, heated to 45 ° C under stirring at 200 rpm, the feed valve and the exhaust valve are opened, and pure ferrous salt solution is added, then the autoclave is sealed, and the 150°C, react for 300 minutes, at this time, the co...

Embodiment 2

[0044] Except that the reaction temperature in the first step of Example 1 was changed to 180° C., the corresponding autogenous pressure was 1.0 Mpa, and the reaction time was changed to 30 minutes, the others were the same as in Example 1.

[0045] The morphology of the product obtained in this embodiment is the same as that in Example 1. The electrochemical performance test method of the product of this embodiment is the same as that of Example 1, and the test results are shown in Table 1.

Embodiment 3

[0060] The first step, hydrothermal synthesis reaction

[0061] 795g or 4mol of FeCl 2 4H 2 O dissolved in water and diluted to 4L, after standing for 12 hours, filtered; 484g of 85% phosphoric acid was dissolved in water and diluted to 1.5L, wherein the pure phosphoric acid was 4.2mol; 2 O was dissolved in water and diluted to 2.5 L.

[0062] Add above-mentioned phosphoric acid solution and lithium hydroxide solution in the autoclave of 10L, then add 1.6g cationic surfactant bis-octyl dimethyl ammonium bromide and 0.8g nonionic surfactant nonylphenol polyoxyethylene ether, After purging the air in the dead volume of the autoclave with an inert gas, seal the autoclave, heat it to 40°C under stirring at 200rpm, open the feed valve and exhaust valve, then add pure ferrous salt solution, and then seal the autoclave , at 140°C, reacted for 480 minutes, the corresponding autogenous pressure was 0.36Mpa, and the Li:Fe:P molar ratio was 3.15:1:1.06. When the reaction was started, ...

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
particle diameteraaaaaaaaaa
Login to view more

Abstract

The invention discloses a hydrothermal synthesis method of lithium-ion battery anode material of lithium iron phosphate, relating two kinds of metal phosphate. The steps are as follows: lithium source and phosphorus source are dissolved in water or mixed with water, and added into the reaction autoclave, the quaternary cationic surfactants and the alkylphenols polyoxyethylene ethers nonionic surfactant is also added into the reaction autoclave, the air in the dead volume of the autoclave inside is purged by the inert gas, the autoclave is sealed and heated to 40-50 DEG C with stirring, a feed valve and an exhaust valve are opened, pure ferrous salting liquid is added into the autoclave, and then the autoclave is sealed for the reaction of the material at 140 to 180 DEG C for 30 to 480 minutes; the mixture ratio of the invention is set as follows: the molar ratio of Li, Fe and P is 3.0-3.15:1:1.0-1.15, and then the resultant is filtered, washed, dried and carbon-coated, thus the lithium iron phosphate is obtained. The lithium iron phosphate which is produced by the invention has the advantages that: the electrochemical performance is excellent, the particle size distribution of which the D50 is between 1.5 um to 2 um is even, the phase purity is above 99 percent and the electronic conductivity of the material is improved.

Description

technical field [0001] The technical solution of the invention relates to a phosphate containing two metals, in particular to a hydrothermal synthesis method of lithium iron phosphate, a cathode material of a lithium ion battery. Background technique [0002] Most commercial lithium-ion batteries currently use LiCoO 2 for the positive electrode material. Due to the LiCoO under overcharge condition 2 It will release active oxygen and cause the organic electrolyte to catch fire, the battery will explode, and other safety issues and higher prices. Therefore, people have been experimenting to develop ideal electrode active materials with excellent performance and easy-to-obtain raw materials. In 1997, Goodenough et al synthesized LiFePO with olivine type 4 and use it as a positive electrode active material. LiFePO 4 The theoretical capacity is 170mAh / g, and the discharge platform is 3.4V. Since there is no volume change during the extraction and insertion of lithium, acti...

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): C01B25/45H01M4/58
CPCY02E60/12Y02E60/10
Inventor 梁广川欧秀芹梁金生徐圣钊王丽
Owner HEBEI LITAO BATTERY MATERIAL
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