Preparation method of spherical lithium iron phosphate cathode material

A lithium iron phosphate, spherical technology, applied in the direction of battery electrodes, electrical components, circuits, etc., can solve the problems of carbon doping or uneven coating dispersion, low electrical conductivity, low packing density, etc., to avoid uneven distribution of elements Uniformity, easy doping, and the effect of reducing multiple mixing processes

Active Publication Date: 2012-05-30
HENAN KELONG NEW ENERGY CO LTD
View PDF7 Cites 9 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

[0006] In view of the problems of low electrical conductivity of lithium iron phosphate materials, uneven carbon doping or coating dispersion, and low bulk density, this paper proposes a technical principle and process for the traditional modification of lithium iron phosphate: first, through the liquid phase Synthesize spherical lithium iron phosphate precursor by method, and then coat the upper layer of high-conductivity metal oxide or metal carbide on the surface of the precursor, thereby synthesizing a spherical lithium iron phosphate with high conductivity and high tap density

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 spherical lithium iron phosphate cathode material
  • Preparation method of spherical lithium iron phosphate cathode material
  • Preparation method of spherical lithium iron phosphate cathode material

Examples

Experimental program
Comparison scheme
Effect test

Embodiment 1

[0025] Weigh 1mol FeC 2 o 4 2H 2 O, 1mol H 3 PO 4 , 1mol of LiOH·H 2 O and 0.008mol V 2 o 3 Prepare 1mol / L, 1mol / L, 1mol / L, 0.008mol / L solutions, and add them into a 10L reaction kettle with an overflow port through a metering pump at a flow rate of 15mL / min, and simultaneously add 3mol / L ammonia water and 2mol / L sodium borohydride are added into a 10L reaction kettle with an overflow port at a flow rate of 5-10mL / min and 15mL / min respectively. Adjust the pH value of the reaction solution to 3.5, control the stirrer speed to 220r / min, and keep the temperature in the reactor at 70°C to make it D 50 The suspension of spherical lithium iron phosphate precursor >3 μm flows out from the overflow port.

[0026]Then it is carried out surface coating treatment according to the following scheme: take polytetrafluoroethylene (PTFE) by spherical lithium iron phosphate precursor: polytetrafluoroethylene=15:1 (wt%), add water and be made into 70% floating liquid ( wt%), according ...

Embodiment 2

[0030] Weigh 1molFeO, 1molH 3 PO 4 , 1mol LiOH·H 2 O and 0.01mol Mg(CH 3 COO) 2 9H 2 O is made into solutions of 1mol / L, 1mol / L, 1mol / L, and 0.01mol / L, and are added into a 10L reaction kettle with an overflow port through a metering pump at a flow rate of 15mL / min, and 3mol / L of Add ammonia water and 2mol / L ascorbic acid into a 10L reaction kettle with an overflow port at a flow rate of 5-10mL / min and 15mL / min respectively. Keep the pH value of the reaction solution at 4, control the stirrer speed to 200r / min, and keep the temperature in the reactor at 85°C to make it D 50 The suspension of the spherical lithium iron phosphate precursor >2 μm flows out from the overflow port.

[0031] Then it is carried out surface coating treatment according to the following scheme: take by weighing styrene-butadiene rubber (SBR) by spherical lithium iron phosphate precursor: styrene-butadiene rubber=16: 1wt%, add water and be made into 65% floating liquid (wt%), press Lithium iron ph...

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
particle sizeaaaaaaaaaa
densityaaaaaaaaaa
densityaaaaaaaaaa
Login to view more

Abstract

A preparation method of a spherical lithium iron phosphate cathode material. The method comprises steps of: 1) preparing lithium source, divalent ferric salt, phosphor salt compound and doped metallic element in a molar ratio of 0.95-1.05:1:1:0.005-0.05 into a solution; adding the solution, reducing agent and precipitating agent into a reaction kettle with an overflow mouth through a metering pump; preparing a spherical lithium iron phosphate precursor through reaction condition control; 2) cladding a layer of nano metal oxide or metallic carbide with excellent conductivity on a surface of the spherical lithium iron phosphate precursor by using polymer as an adjuvant; 3) placing the spherical lithium iron phosphate cladded with metal oxide or metallic carbide in an atmosphere protection furnace, introducing inert atmosphere, insulating for 6-24 h at 500-900 DEG C, cooling naturally to a room temperature to obtain the spherical lithium iron phosphate cladded with metal oxide or metallic carbide conductive film. The lithium iron phosphate material prepared by the method has advantages of uniform chemical components and easily controlled product morphology. Especially, the cladding of metal oxide or metallic carbide enhances conductivity between lithium iron phosphate particles and tap density of the material.

Description

technical field [0001] The invention relates to the technical field of cathode materials for lithium ion batteries, in particular to a method for preparing spherical lithium iron phosphate cathode materials through the process of synthesizing spherical lithium iron phosphate precursors by a liquid phase method and coating them with metal oxides or metal carbides. technical background [0002] Among the many secondary battery systems, lithium-ion batteries have the advantages of high working voltage, high energy density, long cycle life, low self-discharge rate, and environmental protection, and have become the main trend of secondary battery development. Among them, the positive electrode material is an important part of lithium-ion batteries, and the positive electrode materials of commercial lithium-ion batteries include lithium cobalt oxide (LiCoO 2 ), lithium nickelate (LiNiO 2 ), lithium manganese oxide with spinel structure (LiMn 2 o 4 ), lithium iron phosphate (LiF...

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): H01M4/1397H01M4/58
CPCY02E60/122Y02E60/10
Inventor 张天纪魏玲贾金桃徐拥军尹正中程迪
Owner HENAN KELONG NEW ENERGY 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