Process for synthesizing LiFePO4 as positive electrode materials of lithium ion cell

A technology for lithium ferrous phosphate and lithium ion batteries, which is applied in battery electrodes, phosphorus compounds, chemical instruments and methods, etc. It can solve the problem of uneven positive electrode materials in ferrous phosphate, inability to effectively increase material capacity, incomplete mixing, etc. problem, to achieve the effect of thorough mixing, easy mixing, and increased charging capacity

Inactive Publication Date: 2006-09-27
SHANDONG UNIV OF SCI & TECH
View PDF1 Cites 37 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

This preparation method is simple to operate and easy to control, and the prepared product has excellent electrical conductivity. The disadvantage is: since the added carbon is added in the form of solid, the amount of adulteration is relatively small, so it is not easy to mix, and the mixing is not easy. Thoroughly, so that the positive electrode material in the synthesized ferrous phosphate is not uniform, and the capacity of the material cannot be effectively improved

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

Examples

Experimental program
Comparison scheme
Effect test

Embodiment 1

[0016] (1) First, lithium oxalate, ferrous oxalate and ammonium dihydrogen phosphate are uniformly mixed in a ratio of lithium ion: iron ion: phosphate ion molar ratio of 1:1:1 to obtain mixture A

[0017] (2) Take 1 kg of mixture A and put it into 1 kg of aqueous solution B containing glucose and zirconium nitrate and stir evenly. Under nitrogen atmosphere, heat at a heating rate of 20°C / min. When the temperature reaches about 100°C, keep it warm for 5 hours, and then continue to heat up , kept at 700°C for 10 hours, cooled naturally, and synthesized lithium ferrous phosphate powder containing carbon simple substance and doped metal zirconium ions, wherein:

[0018] Require 1kg of aqueous solution B to contain glucose 10g, zirconium nitrate (Zr(NO 3 ) 4 ) 1 g (about 0.003 mole);

[0019] According to step (1), it can be seen that 1kg of mixture A contains 1.62 moles of lithium oxalate (Li 2 C 2 o 4 Molecular weight 102), 3.24 moles ferrous oxalate (FeC 2 o 4 Molecular ...

Embodiment 2

[0022] (1) First, lithium carbonate, ferrous oxalate and ammonium dihydrogen phosphate are uniformly mixed in a ratio of lithium ion: iron ion: phosphate ion molar ratio of 1:1:1 to obtain mixture A

[0023] (2) Take 1kg of mixture A and put it into 1kg of aqueous solution B containing polyvinyl alcohol and magnesium nitrate, stir evenly, heat at a heating rate of 30°C / min under a nitrogen atmosphere, and keep it warm for 4 hours when the temperature rises to about 110°C. Continue to heat up, when the temperature reaches 300 ° C, keep the temperature for 5 hours, then continue to heat up to 700 ° C, keep the temperature for 5 hours, cool naturally, and synthesize lithium ferrous phosphate powder containing carbon element and doped metal magnesium ions, wherein:

[0024] It is required that 1 kg of aqueous solution B contains 10 g of polyvinyl alcohol and 1 g of magnesium nitrate (about 0.004 moles);

[0025] According to step (1), it can be known that 1kg mixture A contains 1....

Embodiment 3

[0028] (1) At first three kinds of materials dilithium hydrogen phosphate, ferrous oxalate and ammonium dihydrogen phosphate are uniformly mixed in the ratio of lithium ion: iron ion: phosphate ion molar ratio is 1: 1: 1 to obtain mixture A;

[0029] (2) Take 1 kg of mixture A and put it into 1 kg of aqueous solution B containing sucrose and magnesium nitrate and stir evenly. Under nitrogen atmosphere, heat at a heating rate of 5°C / min. When the temperature reaches about 90°C, keep it warm for 6 hours, and continue heating. When the temperature reaches 300°C, keep the temperature for 5 hours, then continue to heat up to 700°C, keep the temperature for 5 hours, cool naturally, and synthesize lithium ferrous phosphate powder containing carbon element and doped metal magnesium ions, wherein:

[0030] It is required to contain 10 g of sucrose and 1 g of magnesium nitrate (about 0.004 mole) in 1 kg of aqueous solution B;

[0031] According to step (1), it can be seen that 1kg of mi...

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 Synthesis of lithium ferrous phosphate which is anode material of lithium ion battery. The material synthesis is as follows: geeting lithium salt, malysite and mammonium dihydrogen phosphate, according to the mole ratio of lithium ion: iron ion: phosphate radical ion is (0.8-1.2):(0.8-1.2):(0.8-1.2), getting compound A of equal proportion, joining some compound A in aqueous solution B which contains soluble salt and soluble organic species, putting it in high temperature furnace, then cooling naturely, compounding ferrous phosphate powder containing carbon and adulterating metal ion, milling the synthetical aqueous lithium solution powder, controllong the grain diameter between 1-50 mum. The synthetical material of this invention distribute equally, using this material as positive material can improve batteries' charging capacity effectively.

Description

technical field [0001] The invention relates to a cathode material of a lithium ion battery, in particular to a synthesis method of lithium iron phosphate, an anode material of a lithium ion battery. Background technique [0002] As a green high-energy power source, lithium-ion batteries have been widely valued for more than ten years. It has the characteristics of high energy density, good cycle performance and low self-discharge rate. In recent years, the battery industry generally believes that lithium iron phosphate (molecular formula: LiFePO 4 ) is one of the best new cathode materials for high-energy power batteries. In order to improve the capacity of lithium iron phosphate, carbon and metal ions are generally added during the synthesis process. Chinese Patent Publication No. (Patent No.: 200410039176.4) discloses a preparation method of lithium ferrous phosphate, a positive electrode material for lithium ion batteries. It is to mix lithium salt, ferrous salt, phosph...

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
CPCY02E60/10
Inventor 谷亦杰黄小文崔洪芝
Owner SHANDONG UNIV OF SCI & 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

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