High-silicon-content silicon-carbon negative electrode plate and preparation method thereof

A negative pole piece, silicon carbon technology, applied in the direction of battery electrodes, electrode carriers/current collectors, electrical components, etc., can solve the problems of low electronic conductivity, poor cycle performance, and low potential for lithium extraction and extraction, and achieve improved specific capacity , solve the cost and process difficulty, and alleviate the effect of silicon negative electrode expansion

Pending Publication Date: 2022-01-11
LANXI ZHIDE ADVANCED MATERIALS CO LTD
View PDF4 Cites 0 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

[0002] With the development of economy and society, consumer electronics such as mobile phones and electric vehicles have higher and higher requirements for battery life. The energy density of existing lithium-ion batteries has gradually been unable to meet the demand. Increasing the specific capacity of positive and negative electrode materials is the key to improving battery life. An effective method for energy density, there is no better choice for positive electrode materials at this stage, and the main improvement is in negative electrode materials
Silicon carbon anode is recognized as the next-generation high energy density lithium battery anode material, which has high specific capacity (close to 10 times that of existing graphite anode), low potential for lithium deintercalation (0.2~0.4V vs Li), non-toxic and abundant reserves Rich (the abundance of the earth's crustal elements is second only to oxygen), but there are also disadvantages such as large volume expansion resulting in poor cycle performance, low electronic conductivity resulting in poor rate performance, etc.

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
  • High-silicon-content silicon-carbon negative electrode plate and preparation method thereof
  • High-silicon-content silicon-carbon negative electrode plate and preparation method thereof

Examples

Experimental program
Comparison scheme
Effect test

preparation example Construction

[0022] This embodiment also provides a method for preparing a silicon-carbon negative electrode sheet with a high silicon content, which is characterized in that it includes the following steps:

[0023] S1: Use a double planetary mixer to disperse and homogenize the carbon material and binder A in deionized water or N-methylpyrrolidone according to a certain ratio to obtain a carbon slurry; use an extrusion coating machine to apply the carbon slurry to the current collector Coating and drying on the carbon layer to obtain a pole piece coated with a carbon layer; the solid content of the carbon slurry is not specifically limited, preferably 20%-40%, if the solid content is too high or too low, the viscosity of the slurry will be unsuitable and difficult to apply;

[0024] S2: Use a double planetary mixer to disperse and homogenize the silicon particles, conductive agent and binder B in deionized water or N-methylpyrrolidone according to a certain proportion to obtain a silicon...

Embodiment 1

[0030] SiO silicon particles were selected, and the average particle diameter of the SiO particles in a fully charged state was measured to be 15 μm according to the above method. Use a double planetary mixer to disperse conductive carbon black SP and polyacrylic acid PAA in deionized water at a ratio of 98:2, with a solid content of 25%, and then use an extrusion coater to coat the slurry on copper foil And dry, after coating, the porosity measured by mercury porosimeter and BET specific surface area test method is 66%, and the coating thickness is 35 μm, which meets the requirements of fully charged particle size of silicon particles < thickness of carbon layer × porosity < silicon particles Fully charged state particle size × 2. Disperse and homogenize SiO silicon particles, single-wall carbon nanotube conductive agent SWCNT and polyacrylonitrile PAN binder in N-methylpyrrolidone solvent according to the ratio of 95:1.5:3.5, with a solid content of 45%, and then use extrusi...

Embodiment 2

[0033] Other steps are the same as in Example 1, the difference is that the SiO silicon particles in Example 1 are replaced by nano-silicon particles, and the average particle diameter of the nano-silicon particles in a fully charged state is 8 μm, and the conductive carbon black SP in Example 1 is replaced by Adult artificial graphite, the porosity after coating is 47%, and the coating thickness is 30μm.

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
Thicknessaaaaaaaaaa
Login to view more

Abstract

The invention provides a high-silicon-content silicon-carbon negative electrode plate, which comprises a current collector, a carbon layer formed on the surface of the current collector and a silicon material layer formed on the surface of the carbon layer, and the mass ratio of the carbon layer to the silicon material layer is 5: 95-50: 50. The surface of the current collector is coated with the carbon layer, the thickness and porosity of the current collector are controlled, silicon negative electrode expansion can be greatly relieved, and when a proper silicon negative electrode material is matched, the silicon negative electrode content of 50% or above can be achieved, and then the specific capacity of the pole piece can be greatly improved.

Description

technical field [0001] The invention belongs to the technical field of batteries, and in particular relates to a silicon-carbon negative electrode sheet with high silicon content and a preparation method thereof. Background technique [0002] With the development of economy and society, consumer electronics such as mobile phones and electric vehicles have higher and higher requirements for battery life. The energy density of existing lithium-ion batteries has gradually been unable to meet the demand. Increasing the specific capacity of positive and negative electrode materials is the key to improving battery life. For effective methods of energy density, there is no better choice for positive electrode materials at this stage, and the main improvement lies in negative electrode materials. Silicon carbon anode is recognized as the next-generation high energy density lithium battery anode material, which has high specific capacity (close to 10 times that of existing graphite a...

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): H01M4/133H01M4/134H01M4/66H01M4/38H01M4/583H01M4/62
CPCH01M4/133H01M4/134H01M4/667H01M4/583H01M4/625H01M4/386H01M4/621Y02E60/10
Inventor 姚林林其他发明人请求不公开姓名
Owner LANXI ZHIDE ADVANCED MATERIALS 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