Preparation method of iron phosphate, iron phosphate prepared by method, preparation method of lithium iron phosphate, lithium iron phosphate prepared by method and lithium battery

A technology of lithium iron phosphate and iron phosphate, applied in the field of lithium batteries including lithium iron phosphate and lithium iron phosphate, can solve the problems of poor conductivity, low tap density, unstable performance, etc., and achieve improved filling and tap density. High, energy density enhancement effect

Active Publication Date: 2018-01-09
GUANGZHOU TINCI MATERIALS TECH
View PDF5 Cites 19 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

[0004] However, lithium iron phosphate also has the following shortcomings: poor conductivity, low tap density, and unstable performance
[0006] However, the performance of the existing lithium iron phosphate cathode materials still needs to be further improved, especially in terms of conductivity, tap density and stability.

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
  • Preparation method of iron phosphate, iron phosphate prepared by method, preparation method of lithium iron phosphate, lithium iron phosphate prepared by method and lithium battery
  • Preparation method of iron phosphate, iron phosphate prepared by method, preparation method of lithium iron phosphate, lithium iron phosphate prepared by method and lithium battery
  • Preparation method of iron phosphate, iron phosphate prepared by method, preparation method of lithium iron phosphate, lithium iron phosphate prepared by method and lithium battery

Examples

Experimental program
Comparison scheme
Effect test

preparation example Construction

[0050] A preparation method for an iron phosphate precursor prepared by lithium iron phosphate, said method comprising the following steps:

[0051] Steps to prepare ferrous sulfate : Add reduced iron powder accounting for 15% by weight of the aqueous solution to an aqueous solution containing 30% sulfuric acid and 1-10% organic acid, and control the temperature of the aqueous solution at 60-90°C to allow the reduced iron powder to react with the solution. The time is controlled within 5-10 hours. After the reaction is completed, the first reaction solution is obtained, and the first reaction solution is subjected to high magnetic filtration to remove iron element and high-priced iron ions, thereby obtaining an aqueous solution of ferrous sulfate;

[0052] The organic acid is at least one of lactic acid, malic acid, succinic acid, phytic acid or derivatives thereof (referring to derivatives of lactic acid, malic acid, succinic acid or phytic acid);

[0053] The steps of pre...

Embodiment 1

[0084] The preparation of nano-spherical ferric phosphate: put the iron with high-purity iron content greater than 99.8% into the reaction tank filled with 30% sulfuric acid and 1% phytic acid derivative (in mass fraction) as the lining of the acid solution, After heating to 95°C and fully reacting for 20 hours, the pH value is 3; filter, demagnetize, and remove impurities to obtain a pure ferrous sulfate solution with a concentration of 170g / L. Put 500L of the ferrous sulfate solution into the enamel oxidation kettle. At the same time, 72 kg of dissolved diammonium hydrogen phosphate and 50 kg of oxidant ammonium persulfate were added to the oxidation kettle within 10 minutes, and after full reaction, pressure filtration, demagnetization, cleaning, and impurity removal were obtained to obtain initially pure nano-iron phosphate slurry. The value is 5.

[0085] Use phosphoric acid to adjust the acidic pH value of the initial slurry to 2.5, and fully disperse it, put it into the...

Embodiment 2

[0089] Preparation of nano-spherical ferric phosphate: Put iron with a high-purity iron content greater than 99.8% into a reaction tank filled with 30% sulfuric acid and 5% phytic acid derivatives, heat to 90°C, and fully react for 30 hours. The pH value is 3; filter, Demagnetize and remove impurities to obtain ferrous sulfate solution. Put 400L of ferrous salt solution into the enamel oxidation kettle. At the same time, add 58kg of dissolved diammonium hydrogen phosphate and 58kg of ammonium persulfate into the oxidation kettle within 15 minutes. After fully reacting Press filtration to clean and remove impurities to obtain initially pure nano-iron phosphate slurry.

[0090] Use phosphoric acid to adjust the acidic pH value of the initial slurry to 2.8, add a nanometer control agent to 1%, and fully disperse it, put it into the reaction kettle, heat it to 95°C, and make the initial ferric phosphate form nanocrystals, filter and rinse, and vacuum at 110°C Dry to obtain nano-sp...

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
particle diameteraaaaaaaaaa
densityaaaaaaaaaa
sizeaaaaaaaaaa
Login to view more

Abstract

The invention discloses a preparation method of an iron phosphate precursor particularly suitable for preparation of lithium iron phosphate, iron phosphate prepared by the method, a preparation methodof the lithium iron phosphate and the lithium iron phosphate prepared by the method. The preparation method of the iron phosphate comprises the following steps of adding reduced iron powder to an aqueous solution containing sulfuric acid and organic acid, performing reaction for 5-10 hours at 60-90 DEG C, and performing high-magnetic filtering after reaction is completed to obtain a ferrous sulfate aqueous solution; and dropwise adding a mixture liquid comprising ammonium persulfate, ammonium phosphate and a nanoparticle control agent into the ferrous sulfate aqueous solution, performing precipitation at 60-80 DEG C and a pH value being 3, performing stirring and mixing reaction for 5-8 hours, performing demagnetization and filtering after reaction is completed, pressing to form a filtercake, and performing rinsing, spraying, drying and powder making to obtain an iron phosphate product. By improving a lithium iron phosphate preparation process, preparation processes of a raw materialand the iron phosphate and constituents of the raw material and initial raw material ferrous sulfate, the conductivity, the tap density and the performance stability of the finally-obtained lithium iron phosphate can be fully improved.

Description

technical field [0001] The invention belongs to the field of new energy, and specifically relates to a method for preparing an iron phosphate precursor that is particularly suitable for preparing lithium iron phosphate, iron phosphate prepared by the method, a new method for preparing lithium iron phosphate, and a new type of lithium iron phosphate. Lithium iron phosphate, and lithium batteries including lithium iron phosphate. Background technique [0002] Lithium iron phosphate electrode materials are mainly used in various lithium-ion batteries. Since 1996, Japan's NTT first revealed A y MPO4 (A is an alkali metal, M is a combination of Co and Fe, LiFeCoPO 4 ) Lithium battery anode material with olivine structure, in 1997, John.B.Goodenough and other research groups at Texas State University also reported LiFePO 4 The characteristics of reversibly moving in and out of lithium. The United States and Japan have simultaneously published the structure of olivine (LiMPO 4...

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): H01M4/58H01M10/0525C01B25/26C01B25/45C01B25/37
CPCY02E60/10
Inventor 高延敏
Owner GUANGZHOU TINCI MATERIALS 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