Ferric phosphate lithium material for lithium ion powder cell and preparation method thereof

A lithium iron phosphate and power battery technology, applied in the field of positive electrode materials and their preparation, can solve the problems of difficult industrialized large-scale production, wide particle size distribution range, poor high-rate charge-discharge performance, etc., and achieves high-rate discharge and safety performance. Industrial production, high specific capacity effect

Active Publication Date: 2007-12-05
BTR (TIANJIN) NANO MATERIAL MFG CO LTD
View PDF7 Cites 76 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

However, the particle size distribution range of the product is wide, the crystal size is large, the powder is composed of irregular particles, the bulk density is low, and the tap density is generally only 1.0g / cm 3 About, much lower than the current lithium cobalt oxide (2.8g / cm 3 ), lithium manganate (2.2g / cm 3 ) tap density; and the low electrical conductivity of lithium iron phosphate, high rate charge and discharge performance is poor, resulting in difficulties in the practical application of materials
[0004] In order to improve the performance of lithium iron phosphate, it is generally doped, such as the oxygen site doping disclosed in Chinese patent document CN1772604, the transition element doping disclosed in CN1785799, the rare earth doping disclosed in CN1785800, and the phosphorus site disclosed in CN1785823. Doping, although the above method can partially improve the performance of lithium iron phosphate, it is not easy to realize industrialized mass production

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
  • Ferric phosphate lithium material for lithium ion powder cell and preparation method thereof
  • Ferric phosphate lithium material for lithium ion powder cell and preparation method thereof
  • Ferric phosphate lithium material for lithium ion powder cell and preparation method thereof

Examples

Experimental program
Comparison scheme
Effect test

Embodiment 1

[0030] 740g lithium carbonate (Li 2 CO 3 ), 3600g ferrous oxalate (FeC 2 o 4 2H 2 O) and 2300g ammonium dihydrogen phosphate (NH 4 h 2 PO 4 ), and 50g magnesium hydroxide, add 10kg deionized water, ball mill 24h in the wet stirring ball mill (model SX-30), the medium that uses is the zirconia ball of diameter 1mm, adopts MalvernMS2000 laser particle size analyzer to record the mixture particle The diameter is 200nm. Then add 990g of glucose, continue ball milling for 24 hours, and then use a centrifugal spray granulation dryer to obtain a spherical precursor at an inlet temperature of 250°C and an outlet temperature of 90°C; Inject nitrogen, keep warm at 300°C for 12h, then raise the temperature to 800°C and keep the temperature constant for 24h, and cool down to room temperature naturally; put the above materials into the ultrafine pulverizer, pulverize at 6000rpm for 45min, and then add them to the impact ball mill Inside, the spheroidization process was carried out ...

Embodiment 2

[0034] 840g lithium hydroxide (LiOH·H 2 O), 1600g ferric oxide (Fe 2 o 3 ) and 2300g ammonium dihydrogen phosphate (NH 4 h 2 PO 4 ), 474g magnesia, add 10kg deionized water, ball mill 48h in the wet stirring ball mill (model SX-30), the medium that uses is the zirconia ball of diameter 1mm, adopts MalvemMS2000 laser particle size analyzer to measure the particle size of mixture is 5nm. Then add 990g of glucose, continue ball milling for 4 hours, and then use a centrifugal spray granulation dryer to obtain a spherical precursor at an inlet temperature of 280°C and an outlet temperature of 90°C; put the above precursor into an atmosphere-protected tube furnace, pass Inject nitrogen, keep warm at 400°C for 2 hours, then raise the temperature to 750°C and keep the temperature constant for 20 hours, and cool down to room temperature naturally; put the above materials into the ultrafine pulverizer, pulverize at 6000rpm for 10min, and then add them to the impact ball mill , and...

Embodiment 3

[0036] 740g lithium carbonate (Li 2 CO 3 ), 1600g ferric oxide (Fe 2 o 3 ), 2300g ammonium dihydrogen phosphate (NH 4 h 2 PO 4 ), and 50g magnesium hydroxide, add 10kg deionized water, ball mill 4h in wet stirring ball mill (model SX-30), the medium that uses is the zirconia ball of diameter 1mm, adopts Malvem MS2000 laser particle size analyzer to measure the mixture The particle size is 300nm. Then add 400g of conductive carbon black, continue ball milling for 48 hours, and then use a centrifugal spray granulation dryer to obtain a spherical precursor at an inlet temperature of 250°C and an outlet temperature of 90°C; put the above precursor into an atmosphere-protected tube furnace , feed nitrogen, keep warm at 350°C for 8h, then raise the temperature to 800°C and keep the temperature constant for 20h, then cool down to room temperature naturally; put the above materials into a superfine pulverizer, pulverize at 5000rpm for 80min, and then add them to impact spheroidi...

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 sizeaaaaaaaaaa
specific surface areaaaaaaaaaaa
densityaaaaaaaaaa
Login to view more

Abstract

The present invention discloses lithium iron phosphate material for lithium ion power cell and its preparation process, and dissolves the technological problem of raising the discharge power and safety performance. The lithium iron phosphate material is spherical or spheroid composite particle with one base body of lithium iron phosphate and doping and modifying agent and one coating carbon layer. Its preparation process includes wet ball milling the mixture comprising lithium salt, ferric salt, phosphoric acid, doping and modifying agent and dispersant, spraying to pelletize, heating for pre-treatment, maintaining temperature, cooling, pulverizing and shaping. Compared with available technology, the present invention has the features of high crystallization, single structure, average composite particle size of 5-60 microns, specific surface area of 8.0-15.0 sq m / g, bulk density of 1.4-1.7 g / cu cm, high specific capacity, high safety, etc.

Description

technical field [0001] The invention relates to a positive electrode material of a lithium ion power battery and a preparation method thereof, in particular to a lithium iron phosphate positive electrode material and a preparation method thereof. Background technique [0002] As a new generation of green high-energy batteries, lithium-ion batteries are widely used due to their high voltage, high energy density, good cycle performance, small self-discharge, no memory effect, and wide operating temperature range. Cathode materials are an important part of lithium-ion batteries, and lithium iron phosphate, as a new generation of cathode materials, has become a current research hotspot. Lithium iron phosphate cathode material has many advantages such as high theoretical capacity, about 170mAh / g, non-toxicity, wide selection of raw materials, stable working voltage, stable structure, excellent safety, good thermal stability, high temperature and cycle performance. [0003] The s...

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): C01B25/45C01D15/00C01G49/00H01M4/58H01M4/04
CPCY02E60/10
Inventor 岳敏田强
Owner BTR (TIANJIN) NANO MATERIAL MFG CO LTD
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