Process for solid phase synthesis of lithium iron phosphate anode materials under high pressure

A technology of lithium iron phosphate and cathode material, applied in chemical instruments and methods, phosphorus compounds, battery electrodes, etc., can solve the problems of low charge and discharge current density, low diffusion speed of lithium ions, and limitations of coarse particles, so as to reduce the reaction Time, small grain size, effect of reducing production cost

Inactive Publication Date: 2006-12-27
SOUTH CHINA UNIV OF TECH
View PDF0 Cites 36 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

However, there are still many shortcomings, such as low conductivity, low lithium ion diffusion rate, low charge and discharge current density, and long charge and discharge time.
At present, the most commonly used preparation method of this kind of electrode material is solid-phase synthesis method. Due to the shortcomings of high synthesis temperature, uneven particle size distribution, and coarse particles, this synthesis method cannot completely solve the inherent limitations of the material.

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
  • Process for solid phase synthesis of lithium iron phosphate anode materials under high pressure
  • Process for solid phase synthesis of lithium iron phosphate anode materials under high pressure
  • Process for solid phase synthesis of lithium iron phosphate anode materials under high pressure

Examples

Experimental program
Comparison scheme
Effect test

Embodiment 1

[0023] Will Li 2 CO 3 , FeC 2 o 4 2H 2 O and NH 4 h 2 PO 4 Weigh 45g according to the stoichiometric ratio of Li:Fe:P=1:1:1, mix evenly, and ball mill on a planetary ball mill for 6h; then pretreat at 300°C for 5h under air atmosphere, and after natural cooling, the powder is obtained Shape product; Add low molecular weight phenolic resin 5g as carbon source in above-mentioned powdery product, ball mill 6h again in planetary ball mill, in N 2 Sintering was carried out at 550° C. for 6 hours under a pressure of 10 MPa in an air atmosphere to obtain a carbon-coated lithium iron phosphate cathode material.

[0024] The XRD pattern of the product is shown in figure 1 As shown in the middle a curve, it can be seen from the figure that a lithium iron phosphate cathode material with a pure phase olivine structure was synthesized by using this high-temperature solid-state sintering method. There is no impurity peak in the spectrogram, and the product has high purity. The cyc...

Embodiment 2

[0026] LiNO 3 , FeC 2 o 4 2H 2 O and (NH 4 ) 2 HPO 4 Weigh 50g according to the stoichiometric ratio of Li:Fe:P=1:1:1, mix evenly, and ball mill on a planetary ball mill for 12h; then under air atmosphere, carry out pretreatment at 200°C for 8h, after natural cooling, to obtain Powdered product; then add 1 g of acetylene black as a carbon source to the above powdered product, ball mill it again in a planetary ball mill for 10 h, and sinter at 560 ° C for 6 h in an Ar gas atmosphere to obtain a carbon package Coated lithium iron phosphate cathode material.

[0027] The XRD pattern of the product is shown in figure 1 As shown in the middle b curve, it can be seen from the figure that there is no impurity in the product, and it is a lithium iron phosphate positive electrode material with a pure-phase olivine structure. The first charge and discharge curve of the lithium iron phosphate cathode material at a rate of 0.1C is shown in image 3, the charge and discharge capac...

Embodiment 3

[0029] LiCH 3 COO, FeC 2 o 4 2H 2 O and (NH 4 ) 3 PO 4 Weigh 99g according to the stoichiometric ratio of Li:Fe:P=1:1:1, mix uniformly, and ball mill on a planetary ball mill for 20h; then under air atmosphere, carry out pretreatment at 300°C for 12h, after natural cooling, to obtain powdered product; then add graphite 1g as a carbon source in the above powdered product, and ball mill for 10 h again in the planetary ball mill, in CO 2 Sintering was carried out at 550° C. for 6 hours under a pressure of 15 MPa in an air atmosphere to obtain a lithium iron phosphate cathode material.

[0030] The XRD pattern of the product is shown in figure 1 As shown in the middle c curve, it can be seen from the figure that there is no impurity in the product, and it is a lithium iron phosphate positive electrode material with a pure-phase olivine structure. The first charge and discharge curves of the lithium iron phosphate cathode material at different rates are shown in Figure 4 ...

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 discloses a synthesizing method of anode material of high-pressure solid-phase ferric-lithium phosphate, which comprises the following steps: blending lithium salt, ferric salt and phosphate according to 1:1:1 proportion evenly; grinding the material into ball for 6-24 h to obtain priority; disposing priority for 2-10 h at 200-350 deg.c in the air environment; cooling naturally; grinding to obtain powder material; adding carbon material in the powder material with weight percentage of carbon material at 1-20 percent; grinding again for 6-24 h; disposing for 4-24 h at 450-1000 deg.c in the 1-15 Mpa inert environment; cooling naturally to obtain the product.

Description

technical field [0001] The invention relates to a method for preparing a positive electrode material of a battery, in particular to a method for synthesizing a lithium iron phosphate positive electrode material in a high-pressure solid state. Background technique [0002] Lithium-ion battery is a new generation of green high-energy rechargeable battery after nickel-metal hydride batteries. It is a new power supply system developed rapidly in the early 1990s on the basis of lithium secondary battery research. Due to its outstanding advantages such as high voltage, high energy density, good cycle performance, small self-discharge, and no memory effect, it has developed rapidly in the past 10 years. It has become a tripartite rivalry with nickel-cadmium batteries and nickel-hydrogen batteries in the secondary battery market. With the improvement of performance and the continuous decline of production cost, its market share is still expanding. Lithium-ion batteries have occupie...

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): C01B25/45H01M4/58
CPCY02E60/12Y02E60/10
Inventor 赵彦明董有忠付鹏侯兴梅
Owner SOUTH CHINA UNIV OF TECH
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