Microwave fast solid phase sintering method for cathode material lithium iron phosphate of lithium ionic cell

A lithium-ion battery and lithium iron phosphate technology, applied in battery electrodes, chemical instruments and methods, circuits, etc., can solve the problems of being unsuitable for large-scale industrial production, poor stability of mass production, and reducing sintering time, etc., to achieve excellent pole pieces Processing performance, low cost, and simplified production process

Active Publication Date: 2009-12-02
HENGDIAN GRP DMEGC MAGNETICS CO LTD
View PDF7 Cites 0 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

Although this preparation method produces tap density can reach 2.0-2.2g / cm 3 At room temperature, the first discharge specific capacity can reach 140-160mA / g, which is a lithium-ion battery positive electrode material with high bulk density and high volume specific capacity, spherical lithium iron phosphate, and also greatly reduces the sintering time, but it still uses divalent iron source It is a precursor, thereby greatly increasing the cost of the product; and the microwave equipment used in this method is a household microwave oven, which is only in the laboratory test stage, and the stability of mass production is relatively poor; it is not suitable for large-scale industrial production

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
  • Microwave fast solid phase sintering method for cathode material lithium iron phosphate of lithium ionic cell
  • Microwave fast solid phase sintering method for cathode material lithium iron phosphate of lithium ionic cell
  • Microwave fast solid phase sintering method for cathode material lithium iron phosphate of lithium ionic cell

Examples

Experimental program
Comparison scheme
Effect test

Embodiment 1

[0028] Mix 3080 grams of lithium hydroxide, 5620 grams of ferric oxide, 8261 grams of ammonium hydrogen phosphate and 2240 grams of sucrose, put them into a sand mill, add 8 liters of water, add 20 kilograms of agate balls, and mix for 3.5 hours. Dry the mixed slurry with a spray granulator at a temperature of 200°C, then use a continuous extruder to form a block, and put it into a 2KW microwave reaction furnace. The temperature was raised to 750°C at a rate of 50°C / min, held for 45 minutes, and then cooled to room temperature; after the sintered material was crushed with a crusher, it was graded on a jet mill to obtain lithium iron phosphate with uniform particles.

[0029] The measured carbon content in the material is 5.6%, and its XRD spectrum is shown in figure 1 , compared with the standard card, it is olivine lithium iron phosphate with intact crystal form, no diffraction peak of carbon is observed, indicating that carbon exists as amorphous carbon.

[0030] The measur...

Embodiment 2

[0034] Mix 3695 grams of lithium carbonate, 7985 grams of ferric oxide, 123206 grams of ammonium hydrogen phosphate and 1600 grams of sucrose, put them into a sand mill, add 8 liters of water, add 20 kilograms of agate balls, and mix for 2 hours. The mixed slurry is finely ground with an ultra-fine mill, then dried in an oven at a temperature of 100°C, then made into a block using an extruder, and put into a microwave reaction furnace with a power of 3KW. Under a nitrogen atmosphere of 1 / min, the temperature was raised to 800°C at a rate of 60°C / min, kept for 30 minutes, and then cooled to room temperature. After the sintered material is crushed with a crusher, it is classified on a jet mill to obtain lithium iron phosphate with uniform particles.

[0035] The carbon content of the active material was measured to be 5.8%, and the simulated button battery was prepared according to the method of Example 1. After the battery was assembled, the reversible gram capacity was 148mAh / ...

Embodiment 3

[0037] Mix 30.0 kg of lithium phosphate, 62.2 kg of ferric oxide, 68.7 kg of diammonium hydrogen phosphate, 24.0 kg of sucrose and 12.0 kg of glucose, put them into a mixer, add 50 liters of alcohol, add 200 kg of agate balls, and mix for 2 hours . Then mix with an ultrafine mill for 1 hour, dry the mixed slurry with a spray granulator at a temperature of 180°C, then put the powder into a crucible, and put it into a continuous In a microwave reaction furnace for industrial use, under a nitrogen atmosphere of 10 liters / min, the temperature was raised to 700°C at a rate of 40°C / min, kept for 60 minutes, and then cooled to room temperature. After the sintered material is crushed with a crusher, it is classified on a jet mill to obtain lithium iron phosphate with uniform particles.

[0038] The obtained materials were sent to the lithium-ion battery factory to prepare electrode sheets and assembled into 17500 cylindrical batteries. Under the charge and discharge rate of 0.5C, the...

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
densityaaaaaaaaaa
densityaaaaaaaaaa
Login to view more

Abstract

The invention relates to a microwave rapid solid state sintering method for lithium iron phosphate of lithium ion battery anode material. In the method, lithium salt, Fe<3+> compound, phosphate and additive are mixed according to certain ratio, then the rapid solid state sintering is carried out under the protection of inert gas in a 1.5-5KW microwave sintering furnace and at last grinding is carried out. The method takes the Fe<3+> compound as iron source, which has low cost, easily controllable process parameters and good batch stability and is easy to realize industrial production. The 1.5-5KW microwave sintering furnace is used for carrying out the rapid solid state sintering, which reduces the reaction time from 6-30 hours that is needed traditionally to 20-60 minutes and can greatly simplify production process, improve production efficiency and save energy.

Description

technical field [0001] The invention relates to a preparation method of a positive electrode material of a lithium ion battery, more specifically, the invention relates to a microwave rapid solid-phase sintering method of lithium iron phosphate, a positive electrode material of a lithium ion battery, and belongs to the technical field of lithium ion battery materials. Background technique [0002] In recent years, lithium-ion batteries have developed very rapidly. The demand for lithium-ion batteries in various portable electronic products and communication tools has continued to increase, and large-scale power lithium-ion power supplies are also in the upsurge of development. Cathode materials are an important part of lithium-ion batteries, and the development of new cathode materials has become the key to the development of lithium-ion batteries. LiCoO is currently commercialized on a large scale 2 , high toxicity, high price, and certain safety problems. LiNiO 2 The co...

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 金江剑王国光徐君
Owner HENGDIAN GRP DMEGC MAGNETICS 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