Method for preparing lithium iron phosphate/carbon composite material by thickener doping modification

A carbon composite material, lithium iron phosphate technology, applied in electrical components, battery electrodes, circuits, etc., can solve the problems of lack of cobalt resources, excessive grain growth of product particles, low purity, etc., to achieve large-scale industrial production, The effect of reduced electrode polarization and controllable process flow

Inactive Publication Date: 2013-06-19
HUNAN ZHENGYUAN ENERGY STORAGE MATERIALS & DEVICE INST
View PDF3 Cites 20 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

LiCoO with a layered structure has a high theoretical specific capacity (274 mAh·g-1), and a high tap density (5.1g·cm-3 sup>), but lithium cobalt oxide has disadvantages such as lack of cobalt resources, toxicity, large environmental pollution, high cost, and poor safety.
Compared with lithium cobaltate, lithium nickelate with a layered structure has improved raw materials in terms of cost, source and toxicity, but has disadvantages such as poor thermal stability, toxic raw materials, harsh preparation conditions, and rapid cycle capacity decay.
Lithium manganese oxide cathode material has been greatly improved in terms of safety and price, but the specific capacity is relatively low, and the high-temperature cycle performance is poor
Ternary materials show excellent electrochemical performance and safety performance, but the raw materials contain highly toxic and high-cost cobalt
The disadvantage is that the reactants are usually mixed unevenly, the purity is not high, the product particles and grains grow too large, and it is difficult to control the batch stability of the product, etc.
However, during the preparation process, Fe2+ is easily oxidized, and the pH is difficult to control during the co-precipitation stage. Limited by the precipitation conditions, the selection range of raw materials is small, and a large amount of waste liquid, the production cost is high, and it is difficult to realize industrialization, which affects its practical value

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/carbon composite material by thickener doping modification
  • Method for preparing lithium iron phosphate/carbon composite material by thickener doping modification
  • Method for preparing lithium iron phosphate/carbon composite material by thickener doping modification

Examples

Experimental program
Comparison scheme
Effect test

Embodiment 1

[0024] Weigh 1 mol FeC 2 o 4 2H 2 O, 1 mol NH 4 h 2 PO 4 and 0.4975 mol Li 2 CO 3 , and adding sucrose as a carbon source, ball milling and mixing for 6 hours by ball milling, then putting it into an argon-protected tube furnace, and pretreating at 600°C for 5 hours to obtain the precursor.

[0025] Weigh 0.005mol sodium carboxymethylcellulose, and completely dissolve it in water to form an aqueous solution. Stir the sodium carboxymethyl cellulose aqueous solution with a certain solubility at a high speed under a mechanical mixer, add sucrose therein, and after it dissolves, add the precursor material, and continue stirring at a high speed for a period of time to obtain a uniformly stirred The mixture is dried in an oven. Finally, in an argon-protected tube furnace, heat treatment at 700 °C for 10 h at high temperature to obtain the product Li 0.995 Na 0.005 FePO 4 / C.

[0026] In the above preparation method, the lithium iron phosphate / carbon composite material is...

Embodiment 2

[0029] Weigh 1 mol Fe 2 o 3 , 1 mol H 3 PO 4 and 0.99 mol LiOH, and glucose was added as a carbon source. After ball milling and mixing for 3 hours, it was placed in a nitrogen-protected tube furnace and pretreated at 350 ° C for 3 hours to obtain the precursor.

[0030] Weigh 0.01mol of sodium alginate and dissolve it completely in water to form an aqueous solution. Stir the prepared sodium alginate aqueous solution at high speed under a mechanical stirrer, add glucose to it, and after it dissolves, add the precursor material, continue stirring at high speed for a period of time, and place the uniformly stirred mixture in an oven for drying Dry. Finally, in a nitrogen-protected tube furnace, heat treatment at 600 °C for 6 hours at high temperature to obtain the product Li 0.99 Na 0.01 FePO 4 / C.

[0031] In the above preparation method, the lithium iron phosphate / carbon composite material is prepared by doping and modifying the thickener. The final product adopts a S...

Embodiment 3

[0033] Weigh 1 mol Fe(NO 3 ) 3 9H 2 O, 1 mol (NH 4 ) 3 PO 4 and 0.98 mol LiCH 3 COO, and citric acid was added as a carbon source, ball milled and mixed for 10 h by ball milling, then placed in a nitrogen-protected tube furnace, and pretreated at 500°C for 10 h to obtain a precursor.

[0034] Weigh 0.02mol potassium alginate and dissolve it completely in water to form an aqueous solution. Stir the prepared sodium alginate aqueous solution at high speed under a mechanical mixer, add citric acid to it, and after it dissolves, add the precursor material, continue stirring at high speed for a period of time, and place the uniformly stirred mixture in an oven for drying. Finally, in an argon-protected tube furnace, heat treatment at 600°C for 20 hours at high temperature to obtain the product Li 0.98 K 0.02 FePO 4 / C.

[0035] In the above preparation method, the lithium iron phosphate / carbon composite material is prepared by doping and modifying the thickener. The fina...

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 a lithium ion battery positive electrode material, specifically a lithium iron phosphate / carbon composite material by thickener doping modification, and provides an improvement method for the problems that lithium iron phosphate particles are not uniform, strength of a surface carbon coating layer is unstable, and the like in the prior art. The method has the technical characteristics that a water-soluble organic carbon resource or a conductive carbon black is added in a prepared water solution of the thickener with a certain concentration under mechanical stirring; then precursor powder is added with stirring; and finally the obtained slurry is dried and heat-treated at a high temperature to obtain doped high-performance Li1-xMxFePO4 / C powder with consistent particle morphologies. The method is simple in process, convenient for operations and easy for industrialized production and has relatively wide application prospects.

Description

technical field [0001] The invention relates to a method for preparing a positive electrode material of a lithium ion battery, belonging to the field of material preparation in new energy materials. Background technique [0002] Traditional lithium-ion battery cathode materials include lithium cobalt oxide (LiCoO 2 ), lithium nickelate (LiNiO 2 ), lithium manganate (LiMn 2 o 4 ) and ternary materials (LiNi 1 / 3 co 1 / 3 mn 1 / 3 o 2 )wait. LiCoO with a layered structure has a high theoretical specific capacity (274 mAh g -1 ), and a higher tap density (5.1g cm -3 ), but lithium cobalt oxide has the disadvantages of lack of cobalt resources, toxicity, serious environmental pollution, high cost, and poor safety. Compared with lithium cobalt oxide, lithium nickel oxide with layered structure has improved raw materials in terms of cost, source, and toxicity, but has disadvantages such as poor thermal stability, toxic raw materials, harsh preparation conditions, and rapid cy...

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): H01M4/62H01M4/58
CPCY02E60/10
Inventor 李荐刘凡周宏明黄祖琼刘芙蓉方珍奇
Owner HUNAN ZHENGYUAN ENERGY STORAGE MATERIALS & DEVICE INST
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