Preparation method of carbon-coated lithium iron phosphate with grade structure

A hierarchical structure, lithium iron phosphate technology, applied in structural parts, chemical instruments and methods, phosphorus compounds, etc., can solve problems affecting the chemical and electrochemical properties of products, achieve good development prospects, improve purity, and have a wide range of raw material sources Effect

Inactive Publication Date: 2014-07-30
WUHAN UNIV OF TECH
View PDF3 Cites 15 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

However, with the deepening of the research, it was found that there are often metastable FePO in the structure of the product prepared by the hydrothermal synthesis method. 4 , affecting the chemical and electrochemical properties of the product

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 carbon-coated lithium iron phosphate with grade structure
  • Preparation method of carbon-coated lithium iron phosphate with grade structure
  • Preparation method of carbon-coated lithium iron phosphate with grade structure

Examples

Experimental program
Comparison scheme
Effect test

Embodiment 1

[0035] Take LiAc·2H 2 O, Fe(NO 3 ) 3 9H 2 O, H 3 PO 4 As raw material, 0.01mol LiAc·2H 2 O and 0.01molFe(NO 3 ) 3 9H 2 O was dissolved in 70ml of diethylene glycol (DEG), and after stirring evenly, 0.01mol H 3 PO 4 , stirred for 30min, added 3ml of ethylenediamine (EN) dropwise, stirred for 30min, transferred the stirred solution into a 100ml hydrothermal kettle, heated it at 220°C for 24h, then cooled to room temperature, and deionized the reaction solution After multiple washings with water and ethanol, they were oven dried at 100°C. Dry the spare LiFePO 4 Powder and sucrose (the amount of sucrose added to make the carbon content 4wt%) is mixed and dissolved in deionized water, stirred with a glass rod until dry, and then dried in a vacuum oven at 100°C after stirring, and the dried powder is reduced Atmosphere (5vol.%H 2 and 95vol.% Ar) to 700°C and calcined for 10h. Naturally cooled to room temperature with the furnace to obtain the carbon-coated lithium iron ...

Embodiment 2

[0038] Take LiAc·2H 2 O, Fe(NO 3 ) 3 9H 2 O, H 3 PO 4 As raw material, 0.0102mol LiAc·2H 2 O and 0.01molFe(NO 3 ) 3 9H 2O was dissolved in 35ml of diethylene glycol (DEG), and after stirring evenly, 0.01mol H 3 PO 4 , stirred for 30min, added 3ml of ethylenediamine (EN) dropwise, stirred for 30min, transferred the stirred solution into a 100ml hydrothermal kettle, heated it at 220°C for 24h, then cooled to room temperature, and deionized the reaction solution After multiple washings with water and ethanol, they were oven dried at 100°C. Dry the spare LiFePO 4 Powder and sucrose (the amount of sucrose added to make the carbon content 4wt%) is mixed and dissolved in deionized water, stirred with a glass rod until dry, and then dried in a vacuum oven at 100°C after stirring, and the dried powder is reduced Atmosphere (5vol.%H 2 and 95vol.% Ar) to 700°C and calcined for 10h. Naturally cooled to room temperature with the furnace to obtain the carbon-coated lithium iron...

Embodiment 3

[0041] Take LiAc·2H 2 O, FeCl 3 、H 3 PO 4 As raw material, 0.01mol LiAc·2H 2 O and 0.01mol FeCl 3 Dissolve in 70ml ethylene glycol (EG), stir evenly, add 0.01mol H 3 PO 4 , stirred for 30min, added 4ml of ethylenediamine (EN) dropwise, stirred for 30min, transferred the stirred solution into a 100ml hydrothermal kettle, heated it at 220°C for 36h, then cooled to room temperature, and deionized the reaction solution After multiple washings with water and ethanol, they were oven dried at 100°C. Dry the spare LiFePO 4 Powder and sucrose (the amount of sucrose added to make the carbon content 4wt%) is mixed and dissolved in deionized water, stirred with a glass rod until dry, and then dried in a vacuum oven at 100°C after stirring, and the dried powder is reduced Atmosphere (5vol.%H 2 and 95vol.% Ar) to 750°C and calcined for 10h. Naturally cooled to room temperature with the furnace to obtain the carbon-coated lithium iron phosphate cathode material LiFePO 4 / C.

[004...

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
sizeaaaaaaaaaa
sizeaaaaaaaaaa
sizeaaaaaaaaaa
Login to view more

Abstract

The invention relates to a preparation method of a lithium iron phosphate material as a lithium ion battery positive electrode active substance. The preparation method comprises the following steps: dissolving a lithium source, an iron source and a phosphorus source in a reducing agent, adding a chelating agent, and uniformly stirring to form a mixed solution; performing a hydrothermal reaction; washing and drying to obtain lithium iron phosphate with a grade structure; and mixing with a carbon source, and calcining in a reducing atmosphere to obtain carbon-coated lithium iron phosphate with the grade structure. Compared with the prior art, the preparation method has the beneficial effects that the purity of the product is increased; the reducing agent has a reducing function, the chelating agent has a structure guiding function; the conductivity of lithium iron phosphate is enhanced, and the electrochemical property is improved; a resultant temperature interval is large, and a great application value and a bright development prospect are achieved; the specific capacity is high, the specific surface area is moderate, the cycle performance is good, the repeatability is high, the processing property is excellent, and the demand on a high energy storage device in practical production can be met.

Description

technical field [0001] The invention belongs to the technical field of energy material manufacturing, and in particular relates to a method for preparing a lithium iron phosphate material, which is a positive electrode active material of a lithium ion battery. Background technique [0002] Lithium-ion battery, as a high-performance rechargeable green power source, has been widely used in various portable electronic products and communication tools in recent years, and has been gradually developed as a power source for electric vehicles, thereby promoting its development towards safety, environmental protection, Development in the direction of low cost and high specific energy. Among them, the development of new electrode materials, especially positive electrode materials, is extremely critical. [0003] At present, the widely studied cathode materials for lithium-ion batteries focus on transition metal oxides of lithium such as LiMO with a layered structure. 2 (M=Co, Ni, M...

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): H01M4/58C01B25/45H01M4/62
CPCH01M4/366H01M4/5825H01M4/625H01M10/0525Y02E60/10
Inventor 李昱张倩王洪恩黄绍专苏宝连陈丽华吴旻邓兆
Owner WUHAN 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