Synergistically modified cobalt lithium fluorophosphate cathode material and preparation method thereof

A lithium cobalt fluorophosphate, cathode material technology, applied in nanotechnology for materials and surface science, battery electrodes, electrical components, etc., can solve problems such as low conductivity and poor cycle performance, achieve high energy density, improve Electronic conductivity, effect of protecting structural stability

Active Publication Date: 2018-03-27
UNIV OF JINAN
View PDF1 Cites 4 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

[0005] The purpose of the present invention is to overcome the shortcomings of the positive electrode material such as low electronic and ionic conductivity and poor cycle performance, and prepare nickel-doped and carbon / silicon dioxide-coated synergistically modified lithium cobalt fluorophosphate positive electrode material by hydrothermal method

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
  • Synergistically modified cobalt lithium fluorophosphate cathode material and preparation method thereof
  • Synergistically modified cobalt lithium fluorophosphate cathode material and preparation method thereof
  • Synergistically modified cobalt lithium fluorophosphate cathode material and preparation method thereof

Examples

Experimental program
Comparison scheme
Effect test

Embodiment 1

[0034] (1) LiOH . h 2 O, Co(CH 3 COO) 2 . 4H 2 O, Ni(CH 3 COO) 2 . 4H 2 O, LiF press Li: Co: Ni: the ratio of the amount of F substance is 2.02:0.93:0.07:1 in deionized water and stir evenly, mix H 3 PO 4 , LiF press PO 4 3- : The ratio of the amount of F substance to H is 1:1 3 PO 4 Drop into the above solution, continue to stir for 8 minutes, transfer it to a high-pressure reactor, heat it in water at 200°C for 11 hours, naturally cool to room temperature, take it out, and dry it to obtain the precursor;

[0035] (2) Mix the above-mentioned nickel-doped precursor with the carbon in Ketjen black / ascorbic acid at a mass ratio of 95:5, dry-grind, press into tablets, pre-fire at 350°C for 6 hours in an argon atmosphere, and Cool down, take out and grind, press into tablets, and calcined at 650°C for 5 h to obtain Li 2 co 0.93 Ni 0.07 PO 4 F / C material;

[0036] (3) Weigh 0.5 g of silica powder into a beaker, add ionized water, ultrasonicate for 30 min, then ad...

Embodiment 2

[0038] (1) LiOH . h 2 O, Co(NO 3 ) 2 . 6H 2 O, Ni(NO 3 ) 2 . 6H 2 O and LiF are stirred in deionized water evenly according to the ratio of Li: Co: Ni: F substance amount of 2.02:0.93:0.07:1, and NH 4 h 2 PO 4 , LiF press PO 4 3- : NH in the amount ratio of F substance to 1:1 4 h 2 PO 4 Add it into the above solution, continue to stir for 15 min, transfer it to a high-pressure reactor, heat it in water at 180°C for 15 h, cool it down to room temperature naturally, take it out, and dry it to obtain the precursor;

[0039] (2) After mixing the above-mentioned nickel-doped precursor and the carbon in glucose / sucrose at a mass ratio of 90:10, add an appropriate amount of ethanol, wet mill, dry at 60°C, grind, and press into tablets. Under an argon atmosphere, Precalcined at 400°C for 4 h, quenched the sample in water, ground, pressed into tablets, and calcined at 700°C for 4 h to obtain Li 2 co 0.93 Ni 0.07 PO 4 F / C material;

[0040] (3) Weigh 1.0 g pH=8.5 na...

Embodiment 3

[0042] (1) LiCH 3 COO . 2H 2 O. CoSO 4 . 7H 2 O, NiSO 4 . 6H 2 O and HF are stirred evenly in deionized water according to the ratio of Li: Co: Ni: F substance amount of 2.02:0.93:0.07:1, and NH 4 h 2 PO 4 , LiF press PO 4 3- : NH in the amount ratio of F substance to 1:1 4 h 2 PO 4 Add it into the above solution, continue to stir for 20 min, transfer it to a high-pressure reactor, heat it in water at 120°C for 20 h, cool it down to room temperature naturally, take it out, and dry it to obtain the precursor;

[0043] (2) Mix the above-mentioned nickel-doped precursor with the carbon in carbon nanofibers / pyrrole at a mass ratio of 85:15, dry-grind, press into tablets, and pre-calcine at 300 °C for 7 h in an argon atmosphere, continuously Calcined at 600°C for 5 h to obtain Li 2 co 0.93 Ni 0.07 PO 4 F / C material;

[0044] (3) Weigh 1.0 g of silica particles into a beaker, add ionized water, ultrasonicate for 90 min, then add 1.0 g of the above Li 2 co 0.93 ...

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 a nickel-doped and carbon / silica-coated synergistically modified cobalt lithium fluorophosphates cathode material and a preparation method thereof. The preparation method comprises the following steps: (1) respectively adding a lithium source, a cobalt source, a fluorine source and a nickel source compound into deionized water in a certain stoichiometric ratio, stirring, adding a certain amount of a phosphate source compound into the solution, further stirring, transferring into a high pressure reaction kettle, airtightly heating, reacting, then naturally cooling, taking out, and drying, so that a precursor is obtained; (2) mixing the obtained precursor and a carbon source compound, grinding, and calcining for two stages in inert atmosphere, so that a carbon-coatednickel-doped Li2Co1-xNixPO4F / C material is obtained; and (3) weighing a certain amount of silica, putting into a breaker, adding deionized water, carrying out ultrasonic treatment, then adding the Li2Co1-xNixPO4F / C material, stirring, drying, and grinding, so that the Li2Co1-xNixPO4F / C+SiO2 target material is obtained. The prepared material is uniform in particles and good in crystallinity and has relatively high specific capacity and good cycle performance; and meanwhile, the synthetic process is simple and easy, and the production cost is low.

Description

technical field [0001] The invention relates to a positive electrode material and its preparation, in particular to a cobalt lithium fluorophosphate positive electrode material synergistically modified by nickel doping and carbon / silicon dioxide coating and a preparation method thereof, belonging to the technical field of lithium ion batteries. Background technique [0002] In recent years, the emerging composite polyanionic lithium cobalt fluorophosphate (Li 2 CoPO 4 F) The material has a strong electronegativity F - PO with ions and strong inductive effects 4 3- ions, while exhibiting a high redox potential (4.9 V vs. Li + / Li) and good structural stability, since the material contains two Li + , its theoretical capacity is as high as 287 mAh g -1 , the energy density can reach 1435 Wh kg -1 , is expected to become a hot spot for future development. However, poor ionic and electronic conductivity and cycle performance are the key factors hindering the wide applicat...

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
IPC IPC(8): H01M4/36H01M4/485H01M4/505H01M4/525H01M4/58H01M4/62H01M10/0525B82Y30/00
CPCB82Y30/00H01M4/366H01M4/485H01M4/505H01M4/525H01M4/5825H01M4/625H01M10/0525Y02E60/10
Inventor 常彩云冯季军姜鑫宇
Owner UNIV OF JINAN
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