Fluorine and vanadium ion-doped lithium iron phosphate material and preparation method thereof

A technology of lithium iron phosphate and vanadium ions, applied in chemical instruments and methods, phosphorus compounds, inorganic chemistry, etc., can solve the problem of simultaneously improving the rate performance and discharge potential of lithium iron phosphate, the rate performance and ion conduction of lithium iron phosphate The role of efficiency is not obvious, and the requirements of lithium-ion power batteries cannot be well met, so as to achieve the effect of superior electrochemical performance, cheap raw materials, and easy operation.

Inactive Publication Date: 2012-07-18
SOUTH CHINA UNIV OF TECH
View PDF10 Cites 21 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

[0006] 1. Although fluorine doping can effectively improve the rate performance of lithium iron phosphate, the increase of fluorine ions will lead to a significant decrease in discharge potential, which in turn affects the specific energy and specific power of the battery, which still cannot meet the requirements of lithium-ion power batteries.
[0007] 2. Although vanadium doping can effectively increase the discharge potential of lithiu

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
  • Fluorine and vanadium ion-doped lithium iron phosphate material and preparation method thereof
  • Fluorine and vanadium ion-doped lithium iron phosphate material and preparation method thereof
  • Fluorine and vanadium ion-doped lithium iron phosphate material and preparation method thereof

Examples

Experimental program
Comparison scheme
Effect test

Embodiment 1

[0036] Combine lithium oxalate, iron phosphate, ammonium dihydrogen phosphate, ammonium vanadate and ammonium fluoride according to the molar ratio of ions Li + : Fe 3+ : V 5+ : PO 4 3- : F - =0.97:0.99:0.01:0.99:0.03 Weigh, add glucose according to 25% of the mass of iron phosphate, then add deionized water according to 300% of the total mass of reactant materials, ball mill and mix for 10 hours to obtain a uniform slurry. Then place it in a pit furnace protected by a nitrogen atmosphere, heat it up to 400°C at a rate of 4°C / min for pre-sintering, and keep it for 2 hours; then heat it up at 10°C / min to 750°C for calcination and keep it for 30 hour. After the furnace is naturally cooled to room temperature, it is taken out and ground and passed through a sieve (400 mesh) to obtain lithium iron phosphate co-doped with fluorine and vanadium ions.

[0037] The fluorine and vanadium ion co-doped lithium iron phosphate material prepared by the above method is used as the positive elec...

Embodiment 2

[0039] Combine lithium carbonate, ferric oxide, diammonium hydrogen phosphate, vanadium pentoxide and ammonium fluoride in the molar ratio of Li + : Fe 3+ : V 5+ : PO 4 3- : F - =1:0.9:0.1:0.95:0.15 Weigh, add soluble starch according to 5% of the mass of ferric oxide, then add absolute ethanol according to 150% of the total mass of reactant materials, ball mill and mix for 6 hours to obtain a uniformly mixed The slurry is then placed in a pit furnace protected by a nitrogen atmosphere. The temperature is raised to 350°C at a heating rate of 2°C / min for pre-sintering, and the temperature is kept for 10 hours; then it is heated at 5°C / min to 650°C for calcination , Keep warm for 24 hours. After the furnace is naturally cooled to room temperature, it is taken out and ground and passed through a sieve (400 mesh) to obtain a lithium iron phosphate co-doped with fluorine and vanadium ions. For comparison purposes, fluorine-doped lithium iron phosphate materials and lithium iron phos...

Embodiment 3

[0043] Lithium acetate, iron nitrate, ammonium phosphate, ammonium vanadate and lithium fluoride according to the molar ratio of ions Li + : Fe 3+ : V 5+ : PO 4 3- : F - =1.02:0.95:0.05:0.9:0.3 Weigh, add sucrose according to 50% of the mass of ferric nitrate, then add acetone according to 100% of the total mass of reactant materials, ball mill and mix for 8 hours to obtain a uniform slurry, and then It is placed in a pit furnace protected by a nitrogen atmosphere, heated to 300°C at a heating rate of 1°C / min for pre-sintering and kept for 6 hours; then heated at 15°C / min to 550°C for calcination and kept for 18 hours. After the furnace is naturally cooled to room temperature, it is taken out and ground and passed through a sieve (400 mesh) to obtain lithium iron phosphate co-doped with fluorine and vanadium ions.

[0044] The fluorine and vanadium ion co-doped lithium iron phosphate material prepared by the above method is used as the positive electrode active material to make th...

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
Particle sizeaaaaaaaaaa
Thicknessaaaaaaaaaa
Login to view more

Abstract

The invention discloses a fluorine and vanadium ion-doped lithium iron phosphate material and a preparation method thereof. The fluorine and vanadium ion-doped lithium iron phosphate material has a general chemical formula of LiFe1-yVy(PO4)1-xF3x/C, wherein x is equal to or greater than 0.01 and less than or equal to 0.5; y is equal to or greater than 0.01 and less than or equal to 0.5; and the sum of x and y is equal to or greater than 0.02 and less than or equal to 1.0. The preparation method provided by the invention comprises the following steps of mixing one or more lithium salts, one or more ferric salts, one or more phosphates, one or more carbon sources and doping agents of one or more fluorides and one or more vanadium compounds according to a certain ratio, adding a mixing medium into the mixture, carrying out ball milling mixing, carrying out pre-sintering, carrying out calcining at a high temperature, cooling, and grinding to obtain the fluorine and vanadium ion-doped lithium iron phosphate material. The preparation method provided by the invention realizes synthesis of the fluorine and vanadium ion-doped lithium iron phosphate material by a carbothermal reduction method which is obtained by improvement of the traditional solid phase method. The fluorine and vanadium ion-doped lithium iron phosphate material has excellent multiplying power charge-discharge performances and discharge potential platform electrochemical performances. The preparation method has simple processes, low energy consumption and low costs of raw materials, and is convenient for industrial production.

Description

Technical field [0001] The invention relates to the field of lithium ion battery materials, in particular to a lithium iron phosphate material co-doped with fluorine and vanadium ions and a preparation method thereof. The material can be used in lithium ion batteries, supercapacitors and capacitor batteries. Background technique [0002] Since 1997, J.B.Goodnough[J.Electrochem.Soc.,144(1997)1188] research group first reported olivine-type LiFePO 4 Since it has been used as a cathode material for lithium-ion batteries, LiFePO 4 It has the characteristics of non-toxic, stable structure, high specific capacity, long cycle life, low manufacturing cost, good safety performance and environmental friendliness, and is considered to be one of the most promising cathode materials for lithium ion power batteries. [0003] However, LiFePO 4 The inherently low electronic conductivity and ion conductivity greatly limit its practical application in the field of lithium-ion power batteries. In or...

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): C01B25/45H01M4/58
CPCY02E60/12Y02E60/10
Inventor 周震涛盘茂森
Owner SOUTH CHINA UNIV OF 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