Functional diaphragm coating material for protecting lithium metal negative electrode as well as preparation method and application thereof

A lithium metal negative electrode and coating material technology, which is applied in the direction of lithium batteries, battery pack components, electrical components, etc., can solve the problems of limited lithium ion diffusion rate, reduced battery Coulombic efficiency, and consumption of electrolyte, etc. Ion concentration, reducing space charge effects, slowing the effect of buildup formation

Active Publication Date: 2020-09-22
SOUTH CHINA NORMAL UNIVERSITY
View PDF6 Cites 2 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

[0002] The theoretical specific capacity of lithium metal is 3860 mAh / g, and its standard potential is -3.04 V. Compared with other anode materials, it has obvious advantages and is a promising anode material for lithium batteries. The development of lithium metal batteries, such as the phenomenon of lithium dendrites, as the number of cycles of the battery increases, the dendrites gradually grow, and even pierce the separator, causing safety problems. At the same time, the formation of dead lithium will not only cause the battery Coulombic efficiency At the same time, the SEI film on its surface will also consume the electrolyte. The combination of the above factors means that the commercial application of lithium metal batteries still has a long way to go.
[0003] At present, many researchers have conducted many studies on the formation mechanism of lithium dendrites. However, the growth of lithium dendrites involves many fields such as electrochemistry, interfacial science, crystallography, thermodynamics, etc., and there is still no universal mechanism expression. , one of the theories is that in the lithium ion deposition process, limited by the diffusion rate of lithium ions, there is a concentration gradient in the electrolyte. When the current density increases to a certain level, the lithium ions are exhausted on the lithium negative electrode side. This creates localized space charges leading to the formation of lithium dendrites

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
  • Functional diaphragm coating material for protecting lithium metal negative electrode as well as preparation method and application thereof
  • Functional diaphragm coating material for protecting lithium metal negative electrode as well as preparation method and application thereof
  • Functional diaphragm coating material for protecting lithium metal negative electrode as well as preparation method and application thereof

Examples

Experimental program
Comparison scheme
Effect test

Embodiment 1

[0035] Preparation of a functional separator coating material-trihydroxyaldehyde-hydrazine-covalent organic framework:

[0036] Take 18 mg of 2,4,6-trihydroxy-1,3,5-benzenetricarbaldehyde and 64 μL of hydrazine hydrate (the molar ratio is 2:30), add 3 mL of methanol, 3 mL of tetrahydrofuran, and then add 6 mol / L acetic acid solution, the amount of acetic acid solution added is 10% of the total volume of the above mixture, and then argon gas is introduced and sealed, and the above mixed solution is placed in an oven at 120°C for 72 h, and the obtained reactants are respectively used in 1 , 4-dioxane, tetrahydrofuran and acetone for washing, that is, the red powder membrane coating material - trihydroxy aldehyde - hydrazine - covalent organic framework, such as figure 2 A schematic diagram of the reaction of a trihydroxyaldehyde-hydrazine-covalent organic framework is shown;

[0037] Such as figure 1 It is the SEM scanning image of trihydroxy aldehyde-hydrazine-covalent orga...

Embodiment 2

[0040] Preparation of a functional separator coating material-trihydroxyaldehyde-hydrazine-covalent organic framework:

[0041] Take 18 mg of 2,4,6-trihydroxy-1,3,5-benzenetricarbaldehyde and 85 μL of hydrazine hydrate (the molar ratio is 1:20), add 3 mL of methanol, 3 mL of tetrahydrofuran, and then add 6 mol / L acetic acid solution, the addition of acetic acid solution is 12% of the total volume of the above mixture, then pass through argon and seal it, place the above mixed solution in an oven at 120°C for 72 h, and use 1 , 4-dioxane, tetrahydrofuran and acetone for washing to obtain a red powder diaphragm coating material-trihydroxyaldehyde-hydrazine-covalent organic framework;

[0042] Mix 0.16 g of trihydroxyaldehyde-hydrazine-covalent organic framework, 0.06 g of 5% aqueous binder LA132, and 0.04 g of conductive agent carbon black (the mass ratio of the three is 4:2:1), and then drop 2.4 Prepare the slurry with n-propanol aqueous solution in mL, and coat it on one side o...

Embodiment 3

[0044] Preparation of a functional separator coating material-trihydroxyaldehyde-hydrazine-covalent organic framework:

[0045] Take 18 mg of 2,4,6-trihydroxy-1,3,5-benzenetricarbaldehyde and 71 μL of hydrazine hydrate (the molar ratio is 3:50), add 3 mL of methanol, 3 mL of tetrahydrofuran, and then add 6 mol / L acetic acid solution, the amount of acetic acid solution added is 15% of the total volume of the above mixture, then pass through argon and seal it, place the above mixed solution in an oven at 120°C for 72 h, and use 1 , 4-dioxane, tetrahydrofuran and acetone for washing to obtain a red powder diaphragm coating material-trihydroxyaldehyde-hydrazine-covalent organic framework;

[0046] Mix 0.20 g of trihydroxyaldehyde-hydrazine-covalent organic framework, 0.08 g of 5% aqueous binder LA132 and 0.04 g of conductive agent carbon black (the mass ratio of the three is 5:2:1), and then drop 2 Prepare the slurry with n-propanol aqueous solution in mL, and coat it on one sid...

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
current efficiencyaaaaaaaaaa
Login to view more

Abstract

The invention belongs to the technical field of electrochemical diaphragm materials, and particularly relates to a functional diaphragm coating material for protecting a lithium metal negative electrode as well as a preparation method and application thereof. The diaphragm coating material has a trihydroxy aldehyde-hydrazine-covalent organic framework. 2,4,6-trihydroxy-1,3,5-benzenetricarboxaldehyde and hydrazine hydrate are mixed, an organic mixed solvent is added, a high-temperature reaction is carried out in an inert gas environment, an obtained reaction product is washed and dried, and obtained red powder is the trihydroxy aldehyde-hydrazine-covalent organic framework coating material. The prepared trihydroxy aldehyde-hydrazine-covalent organic framework has abundant polar functional groups which are hydroxyl groups; the coating material is applied to protection of lithium metal, through the lithium affinity effect of polar groups, anions are fixed, dissociation of electrolyte saltis promoted, the migration number of lithium ions is increased, the concentration of the lithium ions near a lithium negative electrode is increased, the space charge effect of cations is reduced, growth of lithium ion tips is reduced, and the performance of lithium dendrites can be effectively inhibited.

Description

technical field [0001] The invention belongs to the technical field of electrochemical diaphragm materials, and in particular relates to a functional diaphragm coating material for protecting lithium metal negative electrodes, a preparation method and application thereof. Background technique [0002] The theoretical specific capacity of lithium metal is 3860 mAh / g, and its standard potential is -3.04 V. Compared with other anode materials, it has obvious advantages and is a promising anode material for lithium batteries. The development of lithium metal batteries, such as the phenomenon of lithium dendrites, as the number of cycles of the battery increases, the dendrites gradually grow, and even pierce the separator, causing safety problems. At the same time, the formation of dead lithium will not only cause the battery Coulombic efficiency At the same time, the SEI film on its surface will also consume the electrolyte. The combination of the above factors means that the co...

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): C07D259/00H01M2/14H01M2/16H01M10/052
CPCC07D259/00H01M10/052Y02E60/10
Inventor 蔡跃鹏洪旭佳袁丽娟邢军伟
Owner SOUTH CHINA NORMAL UNIVERSITY
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