Looking for breakthrough ideas for innovation challenges? Try Patsnap Eureka!

Method for preparing lithium iron phosphate cathode material of lithium ion battery by supercritical hydrothermal process

A lithium-ion battery, lithium iron phosphate technology, applied in the direction of battery electrodes, circuits, electrical components, etc., can solve the problems of shortened reaction time, large particle size, insufficient charge and discharge performance, etc., to achieve shortened reaction time, small particles, The effect of excellent electrochemical performance

Inactive Publication Date: 2012-07-11
DALIAN UNIV OF TECH
View PDF2 Cites 12 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

[0006] The technical problem to be solved by the present invention is to improve the existing large particle size of lithium iron phosphate and insufficient charge and discharge performance, shorten the reaction time to the greatest extent, reduce energy consumption, and reduce production costs, and provide a new lithium ion positive electrode Supercritical hydrothermal synthesis method of material lithium iron phosphate

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
  • Method for preparing lithium iron phosphate cathode material of lithium ion battery by supercritical hydrothermal process
  • Method for preparing lithium iron phosphate cathode material of lithium ion battery by supercritical hydrothermal process
  • Method for preparing lithium iron phosphate cathode material of lithium ion battery by supercritical hydrothermal process

Examples

Experimental program
Comparison scheme
Effect test

Embodiment 1

[0034] The first step, hydrothermal synthesis reaction

[0035] 5.56g of FeSO 4 ·7H 2 O was dissolved in 100 mL of deionized water; 2.306 g of 85% phosphoric acid was dissolved in 50 mL of deionized water; 2.569 g of LiOH·H 2 O was dissolved in 50 mL of deionized water.

[0036] Add the above phosphoric acid solution into the ferrous sulfate solution, stir and mix evenly; then add the lithium hydroxide solution into the mixed solution, finally add 0.3g of polyvinylpyrrolidone, and stir well. Transfer the mixed solution to a 500mL high-temperature and high-pressure reactor, seal the autoclave, use a vacuum pump to extract the air in the dead volume of the reactor, heat the high-temperature and high-pressure reactor to 400°C, adjust the internal pressure of the reactor to 25MPa through a water injection pump, and react for 1 minute. The proportioning control of reaction substance is: Li: Fe: P molar ratio is 3: 1: 1, before starting reaction, reactant concentration is counted...

Embodiment 2

[0049] The first step, hydrothermal synthesis reaction

[0050] 5.56g of FeSO 4 ·7H 2 O was dissolved in 100 mL of deionized water; 2.306 g of 85% phosphoric acid was dissolved in 50 mL of deionized water; 2.569 g of LiOH·H 2 O was dissolved in 50 mL of deionized water.

[0051] Add the above phosphoric acid solution into the ferrous sulfate solution, stir and mix evenly; then add the lithium hydroxide solution into the mixed solution, finally add 0.3g of cetyltrimethylammonium bromide, and stir well. Transfer the mixed solution to a 500mL high-temperature and high-pressure reactor, seal the autoclave, use a vacuum pump to extract the air in the dead volume of the reactor, heat the high-temperature and high-pressure reactor to 380°C, adjust the internal pressure of the reactor to 25MPa through a water injection pump, and react for 10 minutes. The proportioning control of reaction substance is: Li: Fe: P molar ratio is 3: 1: 1, before starting reaction, reactant concentratio...

Embodiment 3

[0058] The first step, hydrothermal synthesis reaction

[0059] 5.56g of FeSO 4 ·7H 2 O was dissolved in 100 mL of deionized water; 2.306 g of 85% phosphoric acid was dissolved in 50 mL of deionized water; 2.569 g of LiOH·H 2 O was dissolved in 50 mL of deionized water.

[0060] Add the above-mentioned phosphoric acid solution into the ferrous sulfate solution, stir and mix evenly; then add the lithium hydroxide solution into the mixed solution, finally add 0.2g of polyvinylpyrrolidone, and stir well. Transfer the mixed solution to a 500mL high-temperature and high-pressure reactor, seal the autoclave, use a vacuum pump to pump out the air in the dead volume of the reactor, heat the high-temperature and high-pressure reactor to 400°C, adjust the internal pressure of the reactor to 30MPa through a water injection pump, and react for 1 minute. The proportioning control of reaction substance is: Li: Fe: P molar ratio is 3: 1: 1, before starting reaction, reactant concentration...

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 sizeaaaaaaaaaa
Login to View More

Abstract

The invention relates to a method for preparing a lithium iron phosphate cathode material of a lithium ion battery by a supercritical hydrothermal process and belongs to the technical field of a novel material. The method comprises the following steps: (1) hydrothermal synthesis reaction, i.e. dissolving an iron source, a phosphorus source, a lithium source and a template agent in water, placing mixes solution into a reaction kettle, pumping out the air in the kettle by adopting a vacuum pump, heating the reaction kettle to the temperature of 380 DEG C to 500 DEG C, regulating the pressure in the kettle into 23MPa to 40MPa by a water injection pump, performing a reaction for 10s to 100min, and controlling the proportion of the added materials into a molar ratio of Li to Fe to P of (3.0 to 3.15):1:(1.0 to 1.15); (2) filtration, washing and drying of a product, i.e. after the reaction is completed, carrying out water-cooling temperature reduction on the reaction kettle and finally, filtering, washing and drying the generated product to obtain gray white LiFePO4 powder; (3) calcining and carbon coating treatment, i.e. calcining the obtained product for 1 to 8 hours at the temperature of 500 DEG C to 800 DEG C in the protective atmosphere to obtain carbon-coated lithium iron phosphate. The product obtained by the method of the invention has excellent electrochemical performance and uniform particle size distribution. The sizes of the particles of the product are in the range of 300nm to 800nm. The phase purity of the product can reach over 99%. The electron conductivity of the material and the diffusion performance of lithium ions are improved.

Description

technical field [0001] The invention relates to a hydrothermal synthesis method of lithium iron phosphate, a positive electrode material of a lithium ion battery, in particular to the synthesis of lithium iron phosphate, a positive electrode material of a lithium ion battery, by using a supercritical hydrothermal one-step liquid phase method, and belongs to the technical field of new materials. Background technique [0002] At present, lithium-ion battery cathode materials mainly include lithium cobalt oxide, lithium manganese oxide, ternary materials, and transition metal phosphates. Commercial lithium-ion batteries are mostly based on LiCoO 2 for the positive electrode material. Due to LiCoO 2 The battery is easy to cause the battery to explode, and there is a serious safety problem. As a strategic resource, cobalt is short of resources, high in cost and high in toxicity, which limits its further development. Lithium manganese oxide cathode materials are rich in resour...

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): H01M4/58
CPCY02E60/12Y02E60/10
Inventor 刘学武魏浩王晋汤洁
Owner DALIAN UNIV OF TECH
Who we serve
  • R&D Engineer
  • R&D Manager
  • IP Professional
Why Patsnap Eureka
  • Industry Leading Data Capabilities
  • Powerful AI technology
  • Patent DNA Extraction
Social media
Patsnap Eureka Blog
Learn More
PatSnap group products

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

© 2024 PatSnap. All rights reserved.Legal|Privacy policy|Modern Slavery Act Transparency Statement|Sitemap|About US| Contact US: help@patsnap.com