A three-dimensional porous lithium negative electrode protected by a surface organic modification layer and its preparation method and application

A three-dimensional porous and modified layer technology, which is applied in the direction of negative electrodes, battery electrodes, lithium batteries, etc., can solve the problems of high energy density advantages of engulfing metal lithium, lower energy density of negative electrodes, uneven distribution of lithium deposition, etc., to achieve suppression of unevenness Effects of deposition, suppression of dendrites, and reduction of average current density

Active Publication Date: 2021-10-26
CENT SOUTH UNIV
View PDF21 Cites 0 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

However, these methods have not fundamentally solved the problem of uneven distribution of lithium deposition, which is not conducive to long-term development
Another example is the patent document CN107785586A, to prepare a three-dimensional porous copper / graphene composite current collector, it is necessary to put the nanoporous metal foil into the quartz boat, which needs to be reacted at high temperature in the atmosphere of argon, hydrogen, acetylene, argon and hydrogen successively , is not conducive to the actual production
The dopamine-coated copper foil and other metal carriers used in patent 201811300712.X, in practical applications, the metal carrier does not provide capacity, but the mass ratio is high, the overall energy density of the negative electrode is reduced, even lower than the graphite negative electrode, the metal carrier will High energy density advantage of devouring lithium metal

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
  • A three-dimensional porous lithium negative electrode protected by a surface organic modification layer and its preparation method and application
  • A three-dimensional porous lithium negative electrode protected by a surface organic modification layer and its preparation method and application

Examples

Experimental program
Comparison scheme
Effect test

Embodiment 1

[0034] (1) SiO with a diameter of 150nm 2 The sphere was used as a template, cassava flour was used as organic carbon, uniformly mixed according to the mass ratio of template to organic carbon of 1:6, carbonized in a tube furnace at 1000 °C for 3 hours, and then the template was cleaned with NaOH with a concentration of 3M / L to obtain the required The porous carbon (the specific surface area is 957m 2 / g; the particle size is 180nm; the pore diameter of the internal communicating pores is 150nm~200nm).

[0035](2) Porous carbon, ferrocene gel (viscosity: 25mPa s; molecular weight: 10000) and PVDF are evenly dispersed in NMP according to the mass ratio of 9:0.5:0.5 to form a uniform slurry, which is coated on the copper foil set On the fluid, the coating thickness is 30μm, and after vacuum drying, the amount of electrodeposited lithium in the coin cell is 5mAh / cm 2 , the three-dimensional porous lithium negative electrode protected by the surface modification layer (thickness...

Embodiment 2

[0049] (1) Fe with a diameter of 350nm 2 o 3 The sphere was used as a template, and glucose was used as organic carbon. According to the mass ratio of template and organic carbon of 1:5, it was uniformly mixed, carbonized in a tube furnace at 1100 °C for 4 hours, and then the template was cleaned with HCl with a concentration of 3M / L to obtain the required The porous carbon (specific surface area is 1083m 2 / g; the particle size is 400nm; the pore diameter of the internal communicating pores is 350nm~400nm).

[0050] (2) Porous carbon, carboxylic acid groups and o-xylene generate gel (viscosity: 30mPa s; molecular weight: 12000) and PVDF are uniformly dispersed in NMP according to the mass ratio of 9:0.5:0.5 to form a uniform slurry, Coated artificial SEI film with a thickness of 150nm, coated on the copper foil current collector with a coating thickness of 30μm, after vacuum drying, the amount of electrodeposited lithium in the button battery is 5mAh / cm 2 , the three-dimen...

Embodiment 3

[0064] (1) Fe with a diameter of 500nm 2 o 3 The sphere is used as template, glucose is used as organic carbon, uniformly mixed according to the mass ratio of template and organic carbon of 1:4, carbonized in a tube furnace at 1200°C, and then the template is cleaned with HCl with a concentration of 3M / L to obtain the desired porous Carbon (specific surface area is 1187m 2 / g; the particle size is 550nm; the pore diameter of the internal communicating pores is 500nm~600nm).

[0065](2) Porous carbon and porphyrin derivatives form gels in ZnP3-cyclohexane (viscosity: 35mPa s; molecular weight: 13000) and PVDF are uniformly dispersed in NMP according to the mass ratio of 9:0.5:0.5 to form Uniform slurry, coated on the copper foil current collector, the coating thickness is 30μm, after vacuum drying, the amount of electrodeposited lithium in the button battery is 5mAh / cm 2 , the three-dimensional porous lithium negative electrode protected by the surface modification layer (th...

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
viscosityaaaaaaaaaa
thicknessaaaaaaaaaa
pore sizeaaaaaaaaaa
Login to view more

Abstract

The invention discloses a three-dimensional porous lithium negative electrode protected by a surface organic modification layer and its preparation method and application, comprising a current collector, porous carbon compounded on the surface of the current collector, and an organic polymer modification layer compounded on the surface of the porous carbon. Porous carbon is a carbon skeleton material with an internal connected pore structure, and the filling chamber formed by the connected holes is filled with lithium metal; the organic polymer is selected from the group consisting of porphyrin derivatives in ZnP 3 ‑One or more of gels generated in cyclohexane, ferrocene gels, blended gels of diamines and lithocholic acid, gels generated by carboxyl amino groups and o-xylene, organic polymerization The viscosity of the product is 15-50mPa·s; the molecular weight is 8000‑15000. The present invention synergistically improves the cycle coulombic efficiency of the metal lithium secondary battery and increases its cycle life through the dual effects of the porous carbon with a high specific surface area and the organic polymer modification layer.

Description

technical field [0001] The invention belongs to the field of new energy devices, and in particular relates to a three-dimensional porous lithium negative electrode protected by a surface modification layer for a secondary battery and a preparation method and application thereof. Background technique [0002] With the increasing awareness of environmental crisis and energy crisis, the field of new energy has gradually become a hot spot in recent years, and battery materials have also attracted more and more attention. Moreover, the energy density of lithium-ion batteries using graphite as the negative electrode at this stage cannot meet the needs of large-scale equipment such as electric vehicles. With its high theoretical specific capacity (3860mAh / g), the lowest electrode potential (-3.040V vs. SHE) and low density (0.53g / cm 3 ), is an ideal negative electrode material in lithium batteries. The safety hazard caused by the high activity of metals limits its commercial appl...

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 Patents(China)
IPC IPC(8): H01M4/134H01M4/62H01M4/1395H01M10/052
CPCH01M4/134H01M4/1395H01M4/628H01M10/052H01M2004/021H01M2004/027Y02E60/10
Inventor 洪波赖延清董庆元高春辉张治安张凯
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