Method for preparing high-performance lithium iron phosphate / carbon anode material by microwave method

A technology of lithium iron phosphate and positive electrode materials, which is applied in battery electrodes, electrical components, circuits, etc., can solve the problems of weak wave absorption ability of lithium iron phosphate, and achieve the effect of easy operation, simple method and remarkable effect

Active Publication Date: 2012-02-08
NINGBO INST OF MATERIALS TECH & ENG CHINESE ACADEMY OF SCI
View PDF5 Cites 12 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

For example, carbon materials have strong absorbing ability, while lithium iron phosphate has relatively weak absorbing ability.

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 high-performance lithium iron phosphate / carbon anode material by microwave method
  • Method for preparing high-performance lithium iron phosphate / carbon anode material by microwave method
  • Method for preparing high-performance lithium iron phosphate / carbon anode material by microwave method

Examples

Experimental program
Comparison scheme
Effect test

Embodiment 1

[0035] Embodiment 1 (comparative test)

[0036] Select ferrous oxalate, lithium hydroxide and ammonium dihydrogen phosphate raw materials, weigh them in a molar ratio of 1:1.02:1 and place them in an aqueous solution, add 8% glucose of the quality of the above raw materials, and simultaneously make the solid content reach 50%. After mixing in a high-energy ball mill for 7 hours until uniform, spray-dried, then placed in a resistance heating furnace, heat-treated at 350°C for 2h under the protection of argon, and then cooled to room temperature at 800°C for 10h to obtain the required phosphoric acid Lithium iron / carbon composite cathode material.

[0037] The scanning electron microscope pictures of the obtained material are shown in figure 1 a, It can be seen that the particles can grow to several microns.

[0038] Electrochemical tests showed that ( figure 2 a), the material has a capacity of 101 mAh / g.

[0039] The conductivity of the material is 2X10 -5 S / cm.

Embodiment 2

[0041] Select ferrous oxalate, lithium hydroxide and ammonium dihydrogen phosphate raw materials, weigh them in a molar ratio of 1:1.02:1 and place them in an aqueous solution, add 8% glucose of the quality of the above raw materials, and simultaneously make the solid content reach 50%. After mixing in a high-energy ball mill for 7 hours until uniform, spray-dried, then placed in a microwave heating furnace, heat-treated at 350°C for 2 hours under the protection of a vacuum atmosphere, and then cooled to room temperature at 800°C for 10 hours to obtain the required iron phosphate Lithium / carbon composite cathode material. The vacuum degree is 5X10 1 Pa.

[0042] The scanning electron microscope pictures of the obtained material are shown in figure 1 b, It can be seen that the particles are about 100-300 nm in size.

[0043] Electrochemical tests showed that ( figure 2 b), the material has a capacity of 154mAh / g.

[0044] The electrical conductivity of the material is 5X1...

Embodiment 3

[0046] Select ferrous citrate, lithium hydroxide and ammonium dihydrogen phosphate raw materials, weigh them in a molar ratio of 1:1.02:1 and place them in an aqueous solution, add 8% polyvinyl alcohol of the quality of the above raw materials, wherein the solid content reaches 50 %, mixed evenly in a high-energy ball mill, sprayed after drying, and then placed in a microwave heating furnace, heat-treated at 350°C for 2h under the protection of a vacuum atmosphere, then heat-treated at 650°C for 10h and cooled to room temperature to obtain the required phosphoric acid Lithium iron / carbon composite cathode material. where the degree of vacuum is 10 2 Pa.

[0047] The material has a capacity of 158mAh / g and a conductivity of about 5X10 -5 S / cm.

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
electrical conductivityaaaaaaaaaa
electrical conductivityaaaaaaaaaa
electrical conductivityaaaaaaaaaa
Login to view more

Abstract

The invention discloses a method for preparing a lithium iron phosphate / carbon anode material under a microwave heating condition with vacuum-protected environment; microwave heating is adopted to promote the graphitization of the carbon material, and the growth of lithium iron phosphate particles is inhibited in vacuum-protected environment; and thus a nanometer lithium iron phosphate / carbon anode material with high conductivity is obtained. The lithium iron phosphate / carbon material prepared by the invention has a conductivity of more than 10-4 S/cm, a particle size of less than 200 nanometers, a specific capacity of more than 140 mAh/g, and has comprehensive performance indexes higher than those of materials prepared by resistor heating in inert atmosphere protected environment under a same condition; and the preparation method is simple in operation, and is applicable to large-scale production.

Description

technical field [0001] The invention belongs to the technical field of energy storage materials, and specifically relates to controlling lithium iron phosphate particles to a nanometer size and increasing the graphitization degree of carbon materials under the conditions of vacuum atmosphere and microwave selective heating, thereby improving the lithium iron phosphate / carbon composite positive electrode. The electronic and lithium ion conductivity of the material improves the rate performance of the material. Background technique [0002] With the depletion of traditional fossil energy and the increasing emphasis on environmental protection, people's demand for new green and efficient energy is increasingly urgent. As a new energy source with a strong competitive advantage, lithium-ion batteries have received special attention. In addition to their wide application in existing small portable batteries, the development prospects of lithium-ion batteries in high-power and high...

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): H01M4/139
CPCY02E60/10
Inventor 刘兆平唐长林王军马池张建刚姚霞银
Owner NINGBO INST OF MATERIALS TECH & ENG CHINESE ACADEMY OF SCI
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