Method for preparing lithium iron phosphate material

A technology of lithium iron phosphate and raw materials, which is applied in the field of preparation of lithium iron phosphate material, a positive active material of lithium ion batteries, can solve the problems of large specific surface area, low tap density, low compaction density, etc., and achieves high specific capacity, high vibration Moderate solid density, the effect of reducing steps

Active Publication Date: 2012-10-24
SICHUAN JINWANGTONG ELECTRONICS SCI & TECH
View PDF5 Cites 19 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

Among them, the lithium iron phosphate material produced by ferrous oxalate has low tap density and large specific surface area, and the lithium iron phosphate material produced by iron oxide has high hardness, large primary particle size, low gram capacity and high density. The compaction density under

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 material
  • Method for preparing lithium iron phosphate material
  • Method for preparing lithium iron phosphate material

Examples

Experimental program
Comparison scheme
Effect test

preparation example Construction

[0031] figure 1 A process flow diagram of a method for preparing a lithium iron phosphate material according to an embodiment of the present invention is shown. like figure 1 The process flow chart of the method for preparing lithium iron phosphate material shown, comprises the following steps:

[0032] Mixing raw materials for preparing lithium iron phosphate materials, including lithium source 101, iron source 102, phosphorus source 103 and carbon source 104;

[0033] Ball milling and drying 105 of the mixed raw materials, ball milling and drying 105 is to put the mixed raw materials into a ball mill for ball milling, and then carry out drying treatment;

[0034] Pre-burn the dried raw materials by 106 ball mill to obtain the precursor of lithium iron phosphate material;

[0035] The precursor of the lithium iron phosphate material obtained by crushing 107 and pre-burning 106;

[0036] The precursor of the lithium iron phosphate material after crushing 107 is subjected t...

Embodiment 1

[0044] The lithium source, the iron source and the phosphorus source are mixed with a mixture of lithium carbonate, ferrous oxalate and ferric oxide and ammonium dihydrogen phosphate in a molar ratio Li:Fe:P=1:1:1, wherein ferrous oxalate and triferrous The mol ratio of ferric oxide is 4:1, adds the sucrose that accounts for all raw material gross mass 2.6% simultaneously;

[0045] Put the mixed raw materials into a ball mill for 3 hours at a speed of 80 rpm, and then put them into a vacuum dryer with a vacuum degree of -0.07MP at 140°C to dry;

[0046]Put the dried material into an atmosphere box furnace for pre-calcination, and pre-fire it at a rate of 8 °C / min in nitrogen atmosphere from room temperature to 350 °C, keep the temperature for 7 hours, and then at a rate of 8 °C / min Down to room temperature, obtain the precursor of lithium iron phosphate material;

[0047] The precursor of the lithium iron phosphate material obtained by pre-burning is crushed by a crusher;

...

Embodiment 2

[0054] The finished product of lithium iron phosphate material is prepared according to the method described in Example 1, the difference is: Lithium source, iron source and phosphorus source take lithium hydroxide, ferrous oxalate and three according to the molar ratio Li:Fe:P=1:1:1 The mixture of ferric oxide and diammonium hydrogen phosphate are mixed, the molar ratio of ferrous oxalate to ferric oxide is 1:1, the secondary sintering temperature is 710°C, and the constant temperature time is 14h.

[0055] The method for preparing a half-cell described in Example 1 was used to make a half-cell from the finished lithium iron phosphate material prepared in this example, and the half-cell was tested, and the results are shown in the following table:

[0056]

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

No PUM Login to view more

Abstract

The invention discloses a method for preparing a lithium iron phosphate material. The method comprises the following steps of: mixing raw materials for preparing the lithium iron phosphate material, wherein the raw materials include a lithium source, an iron source, a phosphorus source and a carbon source, and the iron source is a mixture of ferrous iron and ferric iron; performing ball milling and drying on the mixed raw materials: putting the mixed raw materials into a ball mill for performing ball milling, and drying; pre-burning the ball-milled and dried raw materials to obtain a precursor of the lithium iron phosphate material; crushing the precursor of the lithium iron phosphate material obtained by pre-burning; and performing secondary sintering on the crushed precursor of the lithium iron phosphate material to obtain a finished lithium iron phosphate material. The lithium iron phosphate material prepared with the method has the advantages of high specific capacity, appropriate tap density, appropriate specific surface area, excellent circulating performance and excellent processing performance.

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 batteries have become the main choice of rechargeable power supplies for today's portable products because of their advantages such as large specific energy, high power density, long cycle life, low self-discharge, high performance-price ratio, and less pollution. With the development of lithium-ion batteries, cathode materials have become one of the important bottlenecks restricting the development of lithium-ion batteries. Due to the existence of mixed valence states, transition metals often have relatively ideal electronic conductivity and are not prone to disproportionation reactions. Their oxides have become the first choice for lithium-ion battery cathode materials. As f...

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): C01B25/45
Inventor 刘海润
Owner SICHUAN JINWANGTONG ELECTRONICS SCI & 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