High-purity iron phosphate used for producing lithium ion battery positive-pole material and preparation method thereof

A technology for lithium-ion batteries and cathode materials, which is applied in chemical instruments and methods, phosphorus compounds, inorganic chemistry, etc., can solve the problems of long synthesis cycle, high production cost, high energy consumption and price, etc.

Inactive Publication Date: 2012-10-03
SICHUAN UNIV
View PDF3 Cites 0 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

The advantage of using the high-temperature solid-phase method to prepare iron phosphate is that the process is simple and convenient, and it is easy to operate. The disadvantage is that the synthesis cycle is longer, the energy consumption is higher, and the expensive iron ammonium phosphate is required as a raw material, resulting in higher production costs.

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
  • High-purity iron phosphate used for producing lithium ion battery positive-pole material and preparation method thereof
  • High-purity iron phosphate used for producing lithium ion battery positive-pole material and preparation method thereof
  • High-purity iron phosphate used for producing lithium ion battery positive-pole material and preparation method thereof

Examples

Experimental program
Comparison scheme
Effect test

Embodiment 1

[0068] Example 1 : prepare ferric orthophosphate hydrate according to the present invention

[0069] Purify NH with pH=8, 1.5mol / L 4 HCO 3 The solution was slowly added to 300 mL of refined FeSO4 with pH=3 and Fe concentration of 4.579% under constant stirring. 4 solution, while using a pH meter to detect the pH of the reaction mixture solution, when the pH=7, stop adding the NH 4 HCO 3 Solution, after the bubbles in the reaction system completely disappear, let stand, filter and separate to obtain the filtrate and filter cake, and recover ammonium sulfate, FeCO 3 The filter cake was washed with deionized water until it was washed with Ba(NO 3 ) 2 The solution detection filtrate has no white turbidity;

[0070] Then, the washed FeCO 3 The precipitate was transferred to a beaker, and phosphoric acid with a concentration of 85% was added according to the molar ratio of phosphorus to iron of 1:1, and the stirring was continued for half an hour. During the stirring proces...

Embodiment 2

[0073] Example 2 : prepare ferric orthophosphate hydrate according to the present invention

[0074] Purify NaHCO with pH=8, 2mol / L 3 The solution was slowly added to 300 mL of refined FeSO4 with pH=3 and Fe concentration of 4.579% under constant stirring. 4 In solution, detect the pH of reaction mixture solution with pH meter simultaneously, when pH=6, stop adding described NaHCO 3 Solution, after the bubbles in the reaction system completely disappear, let stand, filter and separate to obtain the filtrate and filter cake, and recover ammonium sulfate, FeCO 3 The filter cake was washed with deionized water until it was washed with Ba(NO 3 ) 2 Solution detection filtrate no white turbidity appears;

[0075] Then, the washed FeCO 3 Transfer the precipitate to a beaker, add phosphoric acid with a concentration of 85% according to the molar ratio of phosphorus to iron 1.5:1, continue to stir for half an hour, heat up to 50 ° C during the stirring process, and let the FeCO ...

Embodiment 3

[0078] Example 3 : prepare ferrous orthophosphate dihydrate according to the present invention

[0079] Purify Na with pH=8, 2.5mol / L 2 CO 3 The solution was slowly added to 300 mL of refined FeCl with pH=2 and Fe concentration of 6.585% under constant stirring. 2 In solution, detect the pH of reaction mixture solution with pH meter simultaneously, when pH=8, stop adding described Na 2 CO 3 Solution, after the bubbles in the reaction system completely disappear, let stand, filter and separate to obtain the filtrate and filter cake, and recover ammonium sulfate, FeCO 3 The filter cake was washed with deionized water until AgNO 3 Solution detection filtrate no white turbidity appears;

[0080] Then, the washed FeCO 3 Transfer the precipitate to a beaker, add phosphoric acid with a concentration of 85% according to the molar ratio of phosphorus to iron 1.3:1, continue to stir for half an hour, heat up to 50 ° C during the stirring process, and let the FeCO 3 The precipitat...

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 relates to high-purity iron phosphate used for producing a lithium ion battery positive-pole material and a preparation method thereof. The preparation method is characterized by comprising the following steps: taking ferrous salt and carbonate as raw materials; reacting to generate intermediate product ferrous carbonate precipitation, wherein, the ferrous carbonate is easy to filter, and the foreign ions are easy to wash; filtering and recovering ammonium sulfate; dissolving the ferrous carbonate precipitation; adding oxidant for oxidizing; regulating the pH value of the solution; heating and preserving the temperature for a certain time to obtain the iron phosphate precipitation; filtering, drying and precipitating to obtain the high-purity iron phosphate; and mixing and calcining the high-purity iron phosphate, the lithium source and the carbon source to obtain the lithium ion battery positive-pole material with excellent electrochemistrical performance. By using the method provided by the invention, the impurity content in the iron phosphate is effectively lowered, the process time is shortened, the energy consumption is reduced, and the cost and the consumption of the raw materials are lowered; and the filter liquor is easy to recover, and the production cost is very low, thus being beneficial for large-scale production in scaled industry.

Description

【Technical field】 [0001] The invention belongs to the technical field of lithium ion battery materials. More specifically, the present invention relates to a method for preparing high-purity iron phosphate used to produce positive electrode materials for lithium-ion batteries; the present invention also relates to the high-purity iron phosphate prepared by the preparation method. 【Background technique】 [0002] At present, lithium-ion batteries are increasingly used in communications, transportation, computers and other industries all over the world, providing countless conveniences for people's lives. And with the improvement of living standards, people pay more attention to resources, environment, safety and other issues. Since the discovery of lithium iron phosphate lithium-ion battery cathode material with olivine structure in 1997, due to its rich source of raw materials, low price, environmental friendliness, good thermal stability and safety, high specific capacity a...

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): C01B25/37
Inventor 刘恒钟本和陈亮
Owner SICHUAN UNIV
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