Method for preparing lithium iron phosphate by using steel slag

A lithium iron phosphate and steel slag technology, applied in chemical instruments and methods, phosphorus compounds, inorganic chemistry, etc., can solve problems such as no public reports, and achieve the effects of ensuring tap density, saving resources, and improving conductivity

Active Publication Date: 2012-01-11
BAOSHAN IRON & STEEL CO LTD +1
View PDF0 Cites 2 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

Metallurgical solid waste steel slag itself contains many 4 Doped metal components, but using steel slag for LiFePO 4 The preparation technology has not been reported publicly

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

Examples

Experimental program
Comparison scheme
Effect test

Embodiment 1

[0014] (1) Weigh 1000 grams of steel slag powder (see Table 1 for the main components of steel slag) and mix it with 100 grams of carbon powder, place it in a high-temperature furnace at 1400 ° C for 2.5 hours of roasting and reduction treatment, take it out and cool it to room temperature. The Fe-P base alloy containing Mn, Cr and other doping elements after reduction treatment is separated by magnetic separation. (2) Oxidize the Fe-P-based alloy obtained by magnetic separation at 650° C. for 3.4 hours in an air environment to obtain a composite oxide. (3) Weigh 440 grams of NH 4 h 2 PO 4 98 g of LiOH was mechanically mixed with the obtained composite oxide to make it uniform. (4) Put the mixed ingredients in a ceramic crucible, bake at 520°C for 8 hours under the protection of nitrogen, and cool to room temperature with the furnace to obtain LiFePO 4 Material.

Embodiment 2

[0016] (1) Take by weighing 1000 grams of steel slag powder (see Table 1 for the main components of steel slag), place it in a high-temperature furnace, feed in a CO reducing gas with a flow rate of 2 liters / min, roast and reduce the reaction for 1.8 hours at 1250° C., take it out and cool it to room temperature. Fe-P based alloy containing appropriate amount of doping elements is obtained by magnetic separation. (2) Oxidize the alloy obtained by magnetic separation at 750° C. for 2.5 hours in an air environment to obtain a composite oxide. (3) Weigh 690 grams (NH 4 ) 2 HPO 4 and 132 g of LiOH were mechanically mixed together with the obtained composite oxide to make it uniform. (4) Put the mixed ingredients in a ceramic crucible, bake at 620°C under the protection of nitrogen for 6 hours, and cool to room temperature with the furnace to obtain LiFePO 4 Material.

Embodiment 3

[0018] (1) Take by weighing 1000 grams of steel slag powder (the main components of steel slag are shown in Table 1), place it in a high-temperature furnace, and feed in a flow rate of 2 liters / minute of H 2 Reducing gas, bake the reduction reaction at 1300°C for 1.5 hours, take it out and cool to room temperature. Fe-P based alloy containing appropriate amount of doping elements is obtained by magnetic separation. (2) The obtained alloy was oxidized at 950° C. for 2.5 hours in an air environment to obtain a composite oxide. (3) Weigh 590 grams of NH 4 h 2 PO 4 and 79 g Li 2 O is mechanically mixed together with the obtained composite oxide to make it uniform. (4) Put the mixed ingredients in a ceramic crucible, bake at 570°C under the protection of argon for 7.5 hours, and cool to room temperature with the furnace to obtain LiFePO 4 Material.

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 relates to a method for preparing phosphate containing over two metals, in particular to a method for preparing lithium iron phosphate. The method for preparing the lithium iron phosphate by using steel slag comprises the following steps: selecting and using the steel slag containing Fe and P and containing more than two elements of Mn, Ti, Cr, V and Ni, and reducing the steel slag at the temperature of between 1,200 and 1,600 DEG C to obtain Fe-P-based alloy containing doped elements; oxidizing the Fe-P-based alloy containing the doped elements at the temperature of between 500and 1,000 DEG C to obtain Fe, P and oxides of the doped elements, namely preparing precursors of LiFePO4; adding a lithium source material, a phosphorus source material or a phosphorus-lithium sourcematerial into the precursors to make the molar ratio of Li to Fe to P in the mixture equal to 1-1.2: 1: 1, and mixing the material and the precursors uniformly; and roasting the mixture at the temperature of between 500 and 700 DEG C under the protection of nitrogen or argon to obtain a multi-element doped LiFePO4 material.

Description

technical field [0001] The invention relates to a preparation method of phosphate containing two or more metals, especially a preparation method of lithium iron phosphate. Background technique [0002] Lithium iron phosphate (LiFePO 4 ) is a lithium-ion battery cathode material. Currently, LiFePO 4 The preparation methods mainly include solid phase sintering method and hydrothermal method. The general process of the solid-state sintering method is to mix the lithium source, iron source and phosphorus source materials uniformly in a certain stoichiometric ratio, sinter under the protection of an inert gas, and cool to room temperature after a certain period of time. The hydrothermal method is to mix the aqueous solution of water-soluble lithium source, iron source and phosphorus source material according to a certain stoichiometric ratio, transfer it to the reaction kettle, keep it at a certain temperature for several hours, and obtain LiFePO after cooling. 4 precipitatio...

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 Patents(China)
IPC IPC(8): C01B25/45H01M4/58
CPCY02E60/10
Inventor 陈荣欢王如意石磊顾德仁吴照金李辽沙武杏荣王平
Owner BAOSHAN IRON & STEEL CO LTD
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