Anion-cation co-doped lithium-rich manganese-based positive electrode material as well as preparation method and application thereof

A lithium-rich manganese-based, positive electrode material technology, applied in the direction of positive electrodes, battery electrodes, active material electrodes, etc., to achieve the effects of inhibiting oxygen release, increasing cycle ratio, and reducing polarization

Pending Publication Date: 2020-12-11
CENT SOUTH UNIV
View PDF9 Cites 2 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

In order to solve the above problems, researchers have done a series of modification work on lithium-rich manganese-based cathode materials, among which cation doping is one of the most effective ways to suppress capacity / voltage fading, which stabilizes the crystal structure and improves lithium ion migration. rate, thereby improving the electrochemical performance of the material, and anion doping is a method to improve the electrochemical performance of the material by affecting the redox of oxygen ions in the structure, but there is still room for improvement in the effect of doping improvement

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
  • Anion-cation co-doped lithium-rich manganese-based positive electrode material as well as preparation method and application thereof
  • Anion-cation co-doped lithium-rich manganese-based positive electrode material as well as preparation method and application thereof
  • Anion-cation co-doped lithium-rich manganese-based positive electrode material as well as preparation method and application thereof

Examples

Experimental program
Comparison scheme
Effect test

Embodiment 1

[0026] According to the general chemical formula (Mn 0.526 Ni 0.421 co 0.053 )CO 3 The precursor 1g powder of the lithium-rich manganese cathode material is mixed with 0.04744g potassium acetate CH3COOK, 0.006108g lithium chloride LiCl and 0.4326g lithium carbonate Li 2 CO 3 Mix evenly, heat up to 500°C at a rate of 2°C / min in an air atmosphere, hold for 5 hours, then raise the temperature to 880°C at a rate of 1°C / min, hold for 15 hours, and cool naturally to room temperature to obtain anion-cation co-doped modification Lithium-rich manganese-based cathode material (chemical formula: Li 1.155 K 0.045 mn 0.421 Ni 0.337 co 0.042 o 1.987 Cl 0.013 ).

[0027] The X-ray diffractometer results of the positive electrode material prepared by the above method are as follows: figure 1 As shown in the figure, it can be seen that the material conforms to the crystal peak of lithium-rich materials, which conforms to α~NaFeO 2 structure, and there is no impurity peak, indicati...

Embodiment 2

[0030] According to the general chemical formula (Mn 0.526 Ni 0.368 co 0.105 )CO 3 1g powder of the precursor of the lithium-rich manganese cathode material and 0.03668g rubidium carbonate Rb 2CO 3 , 0.013847g nickel bromide NiBr and 0.4293g lithium carbonate Li 2 CO 3 Mix evenly, heat up to 500°C at a rate of 2°C / min in an air atmosphere, hold for 5 hours, then raise the temperature to 900°C at a rate of 1°C / min, hold for 15 hours, and cool naturally to room temperature. That is, the anion-cation co-doped modified lithium-rich manganese-based positive electrode material (Li 1.185 Rb 0.015 mn 0.421 Ni 0.29 5 co 0.084 o 1.983 Br 0.017 ). According to the battery test conditions of Example 1, the first-cycle efficiency of the battery of the material of this example is 80%, the capacity retention rate after 100 cycles is 87%, and the average voltage retention rate is 93%.

Embodiment 3

[0032] According to the general chemical formula (Mn 0.526 Ni 0.316 co 0.158 )CO 3 The precursor of lithium-rich manganese cathode material and 0.00702g cesium carbonate Cs 2 CO 3 , 0.0058735g lithium iodide LiI and 0.4932g lithium carbonate Li 2 CO 3 Mix evenly, heat up to 500°C at a rate of 2°C / min in an air atmosphere, hold for 5 hours, then raise the temperature to 880°C at a rate of 1°C / min, hold for 15 hours, and cool to room temperature naturally. That is, the anion-cation co-doped modified lithium-rich manganese-based positive electrode material (Li 1.198 Cs 0.002 mn 0.421 Ni 0.253 co 0.12 6 o 1.996 I 0.004 ). According to the battery test conditions of Example 1, the first cycle efficiency of the battery of the material of this example is 83%, the capacity retention rate after 100 cycles is 90%, and the average voltage retention rate is 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

PropertyMeasurementUnit
diameteraaaaaaaaaa
Login to view more

Abstract

The invention provides a preparation method and application of an anion-cation co-doped lithium-rich manganese-based positive electrode material, which comprises the following steps: uniformly mixingprecursor powder, lithium-containing compound powder, a certain amount of alkali metal M1-containing compound powder and a certain amount of negative valence M2-containing compound powder, carrying out heat treatment at 300-600 DEG C for 3-7 hours, heating to 700-1000 DEG C, and carrying out heat treatment for 8-20 hours. The element M1 replaces Li to inhibit migration of transition metal ions tothe lithium layer so as to stabilize the structure; the element M2 replaces O, so that the release of oxygen can be inhibited. According to the anion-cation co-doped lithium-rich manganese-based positive electrode material, the interlayer spacing is enlarged, the lithium ion migration rate is increased, the structure is stable, the average working voltage is relatively high, and the rate capability and the cycle performance are good.

Description

technical field [0001] The invention relates to a lithium-rich manganese-based cathode material and a preparation method and application thereof, belonging to the technical field of energy storage material design. Background technique [0002] The positive electrode material is the most critical component of lithium-ion batteries, it is the + The source directly determines its energy density and is also an important factor affecting battery power density, cycle life and safety performance. The lithium-rich manganese-based layered cathode material first proposed by Dahn and his colleagues and Thackeray et al. has the advantages of high discharge specific capacity higher than 250mAh / g and high energy density, and is regarded as the main material for the next generation of power batteries. But its average operating voltage of 3.5V is lower than 3.8V of the high-nickel ternary material. In addition, its discharge voltage decays significantly during cycling, leading to a furthe...

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): H01M4/62H01M4/505H01M4/525H01M10/0525
CPCH01M4/505H01M4/525H01M4/628H01M10/0525H01M2004/028Y02E60/10
Inventor 王天硕张春晓韦伟峰江文俊何玮涛
Owner CENT SOUTH 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