A lithium iron phosphate with high compact density and a preparation method thereof

A technology of lithium iron phosphate and positive electrode material, applied in electrical components, electrochemical generators, battery electrodes, etc., can solve the problem that the compaction density and material properties of the pole pieces need to be further improved, the large particles and small particles are effectively filled, and the large and small particles are difficult to achieve. problems such as uniform mixing, to achieve the effect of directional and controllable growth, promotion of stability, and reduction of internal resistance

Active Publication Date: 2019-01-11
SHENZHEN DYNANONIC
View PDF11 Cites 14 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

[0007] However, the above solutions all have the problems of complex preparation methods, difficulty in mixing large and small particles evenly, and difficulty in effectively filling the gaps between large particles with small particles, which leads to further improvement in the compaction density and material properties of the pole piece.

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
  • A lithium iron phosphate with high compact density and a preparation method thereof
  • A lithium iron phosphate with high compact density and a preparation method thereof
  • A lithium iron phosphate with high compact density and a preparation method thereof

Examples

Experimental program
Comparison scheme
Effect test

Embodiment 1

[0079] This embodiment prepares high compacted density lithium iron phosphate according to the following method:

[0080] (1) Provide the lithium iron phosphate precursor prepared by the solid phase method; place the lithium iron phosphate precursor prepared in step 1 and the nano-alumina catalyst in a ball mill for ball milling and mixing, and after mixing, obtain a mixed material; nano-alumina catalyst The mass fraction of the lithium iron phosphate precursor is 0.01%, and the particle size of the nanocatalyst is 1-4nm;

[0081](2) The mixed material is sintered in a nitrogen atmosphere, and at the same time, ethanol is intermittently introduced, and the mass of ethanol is 10% of the mass of the lithium iron phosphate precursor. The sintering operation is as follows: firstly, the temperature is raised to 300°C at a rate of 15°C / min and kept for 4 hours, then the temperature is raised from 300°C to 500°C at a rate of 30°C / min and kept for 16 hours, and then at a rate of 15°C / ...

Embodiment 2

[0087] This embodiment prepares high compacted density lithium iron phosphate according to the following method:

[0088] (1) Prepare the lithium iron phosphate precursor by liquid phase method; deposit titanium dioxide onto the surface of the lithium iron phosphate precursor prepared in step 1 by vapor phase deposition to obtain a mixed material; the nanometer titanium dioxide catalyst accounts for the mass of the lithium iron phosphate precursor The fraction is 1%; the particle size of the nano catalyst is 3-8nm;

[0089] (2) The mixed material is sintered in a nitrogen atmosphere, and at the same time, ethanol is intermittently introduced, and the mass of ethanol is 10% of the mass of the lithium iron phosphate precursor. The sintering operation is as follows: firstly, the temperature is raised to 500°C at a rate of 5°C / min and kept for 1 hour, then the temperature is raised from 500°C to 700°C at a rate of 10°C / min and kept for 3 hours, and then the temperature is raised a...

Embodiment 3

[0093] This embodiment prepares high compacted density lithium iron phosphate according to the following method:

[0094] (1) Provide a lithium iron phosphate precursor; dissolve the lithium iron phosphate precursor and magnesium oxide in a solvent to obtain a mixed material; the mass fraction of the nano-magnesium oxide catalyst in the lithium iron phosphate precursor is 2%; the particle size of the nano-catalyst The diameter is 6-10nm;

[0095] (2) The mixed material is sintered in a nitrogen atmosphere, and at the same time, ethanol is intermittently introduced, and the mass of ethanol is 10% of the mass of the lithium iron phosphate precursor. The sintering operation is as follows: firstly, the temperature is raised to 400°C at a rate of 10°C / min and kept for 2 hours, then the temperature is raised from 400°C to 600°C at a rate of 20°C / min and kept for 10 hours, and then at a rate of 12°C / min Raise the temperature from 600°C to 800°C and keep it warm for 2 hours; after si...

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
diameteraaaaaaaaaa
thicknessaaaaaaaaaa
Login to view more

Abstract

The invention provides a lithium iron phosphate with high compact density and a preparation method thereof. The lithium iron phosphate positive electrode material comprise large particles of lithium iron phosphate and small particle of lithium iron phosphate, wherein that small particles of lithium iron phosphate are filled in the voids between the large particle of lithium iron phosphate, and theshape of the small particles of lithium iron phosphate comprises a spherical shape. A method for prepare that lithium iron phosphate precursor comprises sinter the lithium iron phosphate precursor ina protective gas atmosphere, wherein the sintering is three-stage sintering, the sintering temperature of the three-stage sintering is sequentially increased, and aft the three-stage sintering is finished, the lithium iron phosphate positive electrode material is obtained; Wherein the shape of the lithium iron phosphate precursor comprises a spherical shape. The compaction density of the lithiumiron phosphate with high compaction density provided by the invention can reach 2.7 g/cm3, the electrochemical performance is excellent, the first discharge specific capacity of 1C can reach 150 mAh/g, and the capacity retention rate of 50 cycles of 1C can reach 99.9%.

Description

technical field [0001] The invention belongs to the technical field of energy storage and relates to lithium ion battery materials, in particular to a high compacted density lithium iron phosphate and a preparation method thereof. Background technique [0002] At present, the anode materials of lithium-ion batteries mainly include lithium iron phosphate and ternary materials. Because lithium iron phosphate has a stable P-O bond, it is difficult to decompose. Even under high temperature or overcharge conditions, the structure will not collapse and has good performance. Cycle performance and safety, so it has broad application prospects. However, the energy density of the battery system composed of it is low, which limits its application in power batteries. [0003] In order to increase the energy density of lithium iron phosphate batteries, it is necessary to increase the capacity, voltage platform or compaction density of lithium iron phosphate, but the capacity and voltage...

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): H01M4/36H01M4/58H01M4/62H01M10/0525
CPCH01M4/366H01M4/5825H01M4/625H01M10/0525Y02E60/10
Inventor 孔令涌尚伟丽陈彩凤任望保
Owner SHENZHEN DYNANONIC
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