CN115101730A - Silicon-based composite negative electrode material and preparation method thereof - Google Patents

Silicon-based composite negative electrode material and preparation method thereof Download PDF

Info

Publication number
CN115101730A
CN115101730A CN202210700892.0A CN202210700892A CN115101730A CN 115101730 A CN115101730 A CN 115101730A CN 202210700892 A CN202210700892 A CN 202210700892A CN 115101730 A CN115101730 A CN 115101730A
Authority
CN
China
Prior art keywords
silicon
based composite
negative electrode
carbon nano
composite negative
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Pending
Application number
CN202210700892.0A
Other languages
Chinese (zh)
Inventor
谭龙
苏恒榕
汤昊
熊文俊
幸振
孙润光
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Nanchang University
Original Assignee
Nanchang University
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Nanchang University filed Critical Nanchang University
Priority to CN202210700892.0A priority Critical patent/CN115101730A/en
Publication of CN115101730A publication Critical patent/CN115101730A/en
Pending legal-status Critical Current

Links

Classifications

    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • H01M4/00—Electrodes
    • H01M4/02—Electrodes composed of, or comprising, active material
    • H01M4/36—Selection of substances as active materials, active masses, active liquids
    • H01M4/362—Composites
    • H01M4/366—Composites as layered products
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • H01M10/00—Secondary cells; Manufacture thereof
    • H01M10/05—Accumulators with non-aqueous electrolyte
    • H01M10/052—Li-accumulators
    • H01M10/0525—Rocking-chair batteries, i.e. batteries with lithium insertion or intercalation in both electrodes; Lithium-ion batteries
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • H01M4/00—Electrodes
    • H01M4/02—Electrodes composed of, or comprising, active material
    • H01M4/36—Selection of substances as active materials, active masses, active liquids
    • H01M4/38—Selection of substances as active materials, active masses, active liquids of elements or alloys
    • H01M4/386—Silicon or alloys based on silicon
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • H01M4/00—Electrodes
    • H01M4/02—Electrodes composed of, or comprising, active material
    • H01M4/36—Selection of substances as active materials, active masses, active liquids
    • H01M4/48—Selection of substances as active materials, active masses, active liquids of inorganic oxides or hydroxides
    • H01M4/483—Selection of substances as active materials, active masses, active liquids of inorganic oxides or hydroxides for non-aqueous cells
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • H01M4/00—Electrodes
    • H01M4/02—Electrodes composed of, or comprising, active material
    • H01M4/36—Selection of substances as active materials, active masses, active liquids
    • H01M4/58—Selection of substances as active materials, active masses, active liquids of inorganic compounds other than oxides or hydroxides, e.g. sulfides, selenides, tellurides, halogenides or LiCoFy; of polyanionic structures, e.g. phosphates, silicates or borates
    • H01M4/583—Carbonaceous material, e.g. graphite-intercalation compounds or CFx
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • H01M4/00—Electrodes
    • H01M4/02—Electrodes composed of, or comprising, active material
    • H01M4/36—Selection of substances as active materials, active masses, active liquids
    • H01M4/60—Selection of substances as active materials, active masses, active liquids of organic compounds
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • H01M4/00—Electrodes
    • H01M4/02—Electrodes composed of, or comprising, active material
    • H01M2004/026—Electrodes composed of, or comprising, active material characterised by the polarity
    • H01M2004/027—Negative electrodes

Landscapes

  • Chemical & Material Sciences (AREA)
  • Chemical Kinetics & Catalysis (AREA)
  • Electrochemistry (AREA)
  • General Chemical & Material Sciences (AREA)
  • Composite Materials (AREA)
  • Engineering & Computer Science (AREA)
  • Inorganic Chemistry (AREA)
  • Materials Engineering (AREA)
  • Manufacturing & Machinery (AREA)
  • Battery Electrode And Active Subsutance (AREA)

Abstract

The invention discloses a silicon-based composite anode material and a preparation method thereof, wherein the silicon-based composite anode material comprises a silicon-based material, a one-dimensional carbon nano-material and Schiff base coated on the surface, and the preparation method comprises the following steps: ultrasonically dispersing and assembling the silicon-based material and the one-dimensional carbon nano material in tetrahydrofuran, adding a material for synthesizing Schiff base, heating in water bath, stirring, filtering and drying to obtain the silicon-based composite negative electrode material. In the silicon-based composite negative electrode material prepared by the invention, the one-dimensional carbon nano material can enhance the conductivity of the silicon-based negative electrode, the Schiff base of the surface coating layer can inhibit the volume expansion of the silicon-based negative electrode, the carbon-nitrogen double bond of the silicon-based composite negative electrode material improves the ionic conductivity, inhibits the growth of lithium dendrites and reduces lithium ions consumed by first charge and discharge; therefore, the silicon-based composite negative electrode material provided by the invention can reduce the irreversible capacity of the battery and improve the first coulombic efficiency and the cycling stability of the battery.

Description

Silicon-based composite anode material and preparation method thereof
Technical Field
The invention belongs to the technical field of lithium ion batteries, and particularly relates to a silicon-based composite negative electrode material and a preparation method thereof.
Background
With the exhaustion of fossil fuels and the increasing demand for energy, the problem of developing new energy is imminent. Lithium ion batteries have received much attention due to their excellent energy storage properties and power supply characteristics. At present, the application of lithium ion batteries in the fields with low requirements on energy density, such as mobile phones, notebook computers, electric tools and the like, is nearly mature, but the application of lithium ion batteries in the fields with high requirements on energy density, such as automobile power batteries and the like, has a great space for improving the energy density. Graphite is used as a common cathode material in a lithium ion battery, the theoretical gram capacity of the graphite is only 372mAh/g, and the high-end graphite material in the market can reach 360-365mAh/g, so that the promotion space of the energy density of the corresponding lithium ion battery is quite limited.
Silicon-based materials have high theoretical gram capacity and low lithium removal potential, are environmentally friendly, abundant in reserves and low in cost, and have been widely concerned. However, during the first charge and discharge of the silicon-based material, an SEI film is formed on the surface of the negative electrode, and active lithium is consumed; in addition, the silicon-based material has huge volume expansion in the charging and discharging processes, so that an SEI film can be continuously broken and grown, active lithium in the electrolyte is lost, and the battery performance is greatly reduced; in addition, silicon has poor conductivity, and a large proportion of conductive carbon black is required to enable the electronic conductivity of the electrode to meet the requirements of the battery. Therefore, a large number of workers have been dealing with silicon-based materials in an attempt to solve the problems of the silicon-based materials.
CN110137485B discloses a method for preparing an artificial SEI film, which comprises coating a layer of polyacrylate, carboxymethyl cellulose salt or alginate polymer film on the surface of a silicon material by solvent evaporation or spray drying, and coating a PAN microporous film on the surface of the polymer film by the same method to obtain a silicon negative electrode material containing a surface modification film. The existence of the surface modification film can improve the volume expansion of the silicon material in the circulating process, but the PAN and the lithium electrode have poor compatibility and serious passivation phenomenon, and the circulating stability of the silicon cathode material is reduced.
CN108963229B discloses a preparation method of a high-performance silicon cathode active material, which comprises the steps of preparing a conductive coating solution, preparing a nano-silicon dispersion solution, preparing the silicon active material by a coaxial electrostatic spinning method, and finally drying to obtain the silicon cathode active material. The prepared silicon cathode active material has a core-shell structure, can participate in electrode reaction, exerts the high-capacity characteristic of the silicon cathode material, can solve the problem of poor conductivity of the silicon material and limits the volume expansion of the nano silicon by a shell layer, but has the disadvantages of complex preparation method, high cost and unsuitability for large-scale production.
The above reports cannot solve the problems of SEI film breakage and poor electronic conductivity of the pole piece caused by volume expansion of the silicon-based negative electrode material in the charging and discharging processes, and further influence the reversible capacity, the first coulombic efficiency and the cycling stability of the battery.
Disclosure of Invention
Aiming at the defects of the prior art, the invention aims to provide a silicon-based composite anode material and a preparation method thereof. According to the invention, a silicon-based material and a one-dimensional carbon nano material are subjected to ultrasonic dispersion, and meanwhile, Schiff base is synthesized on the surface of the silicon-based material and the one-dimensional carbon nano material to construct an artificial SEI film, so that the artificial SEI film is not cracked in the expansion process; the method is beneficial to improving the ionic conductivity, inhibiting the growth of Li dendritic crystals and further improving the first reversible capacity, the first coulombic efficiency and the cycling stability of the battery.
In order to achieve the purpose, the invention adopts the technical scheme that:
in a first aspect, the invention provides a silicon-based composite anode material, which comprises a silicon-based material, a one-dimensional carbon nanomaterial and Schiff base wrapping the silicon-based material and the one-dimensional carbon nanomaterial.
The Schiff base organic matter with good flexibility is coated on the surface of the silicon-based material to play a role of an artificial SEI film, and the Schiff base organic matter is insoluble in organic solvents such as EC and DMC, so that the volume expansion of the silicon-based material in the circulation process can be relieved, and the stability of the artificial SEI film is improved.
The silicon-based composite negative electrode material can reduce the irreversible capacity of the battery and improve the first coulombic efficiency and the cycling stability of the battery.
Further, the silicon-based material comprises a pure silicon material, a silicon carbon material and a silicon oxygen material; preferably, the silicon-based material is a pure silicon material.
Further, the one-dimensional carbon nano material comprises carbon nano tubes and carbon nano fibers; preferably, the carbon nanotubes are single-walled carbon nanotubes; preferably, the pipe diameter of the single-walled carbon nanotube is 1-2 nm.
Further, the thickness of the Schiff base wrapping the silicon-based material and the one-dimensional carbon nano material is 0.5-50 nm; preferably, the schiff base is 5nm thick.
Further, the content of the one-dimensional carbon nano material is 0.01-0.3% of the mass of the silicon-based composite negative electrode material, wherein the mass of the silicon-based composite negative electrode material is 100%; preferably, the content of the one-dimensional carbon nanomaterial is 0.04% -0.05%.
Further, the content ratio of the silicon-based material, the one-dimensional carbon nano material and the Schiff base is (95-99) to (0.01-0.1) to (0.1-5) based on 100% of the mass of the silicon-based composite negative electrode material.
Further, the Schiff base is synthesized from one of terephthalaldehyde, isophthalaldehyde and 4, 4 ' -biphenyldicarboxaldehyde and one of 2, 4, 6-tris (4-aminophenyl) -1, 3, 5-triazine, 4 ' -diaminodiphenyl ether and 3, 3 ' -diaminobenzidine.
Preferably, the schiff base is synthesized from terephthalaldehyde and 2, 4, 6-tris (4-aminophenyl) -1, 3, 5-triazine.
Preferably, acetic acid is added during the synthesis for catalysis and heating in a water bath.
In the invention, the one-dimensional carbon nano material and the silicon-based material are assembled together, so that the cycle performance of the silicon-based material can be further improved. The one-dimensional carbon nanomaterial has excellent mechanical rigidity and tensile strength due to the nanostructure and interatomic bonding strength. The one-dimensional carbon nano material also has certain chemical stability and high conductivity, and can greatly enhance the conductivity of the silicon-based material.
In a second aspect, the present invention provides a method for preparing a silicon-based composite anode material according to the first aspect, wherein the method comprises the following steps:
ultrasonically dispersing and assembling a silicon-based material and a one-dimensional carbon nano material in tetrahydrofuran, adding a Schiff base synthesis material, heating in a water bath at 60-90 ℃, stirring, adding 5mL of acetic acid with the concentration of 6mol/L for catalysis, continuously stirring for 12-48h, and then filtering and drying to obtain the silicon-based composite negative electrode material.
Preferably, the water bath temperature is 70 ℃.
Preferably, the stirring time is 24 h.
Compared with the prior art, the invention has the following beneficial effects:
(1) according to the invention, Schiff base with good flexibility is coated on the surface of the silicon-based material to play a role of an artificial SEI film, so that the volume expansion of the silicon-based material in the circulation process can be relieved, the stability of the artificial SEI film is improved, the ionic conductivity can be improved, the growth of lithium dendrites and side reactions between metal lithium and electrolyte can be inhibited, the irreversible capacity of the battery can be further reduced, and the first coulombic efficiency of the battery can be improved. Meanwhile, the doped single-walled carbon nanotube has good conductivity, can improve the conductivity of a silicon-based material, and improves the cycle stability.
(2) The Schiff base coating provided by the invention has good flexibility, can further strengthen the inhibition effect on the growth of lithium dendrites and the side reaction between metal lithium and electrolyte, and can greatly improve the stability of the artificial SEI film; meanwhile, carbon-nitrogen double bonds contained in the Schiff base are matched, so that the binding capacity between the silicon-based material and the single-walled carbon nanotube is improved, the artificial SEI film is not fallen off in the lithium desorption process, and the problem of the cracking growth of the SEI film in the circulation process of the silicon-based negative electrode material is solved.
(3) The preparation method is simple and is easy to realize large-scale production.
Detailed Description
The technical solutions of the present invention are further illustrated below by specific embodiments, which are only for the understanding of the present invention and should not be construed as specifically limiting the present invention.
Example 1
Weighing 5g of silicon powder and 0.05g of single-walled carbon nanotube, placing the silicon powder and the single-walled carbon nanotube into tetrahydrofuran for ultrasonic dispersion, adding 0.804g of terephthalaldehyde and 0.708g of 2, 4, 6-tris (4-aminophenyl) -1, 3, 5-triazine, heating in a water bath at 70 ℃, stirring for 24 hours, adding 5mL of acetic acid with the concentration of 6mol/L for catalysis, and then filtering and drying to obtain the silicon-based composite negative electrode material.
The silicon-based composite negative electrode material prepared in the embodiment is mixed with conductive carbon black, CMC and SBR according to the mass ratio of 16: 2: 1 and evenly coated on the surface of copper foil to prepare the pole piece. And assembling the obtained pole piece, a metal lithium piece counter electrode, LX-025 electrolyte and a Celgard2400 type diaphragm into a button battery, and performing charge and discharge tests on the manufactured button battery. The charging and discharging voltage used in the test process is 0.01-1.5V, and the current density is 300 mA-g -1 . The sample test results are shown in table 1.
Example 2
Weighing 5gSi/SiO X And putting the powder and 0.05g of single-walled carbon nanotube into tetrahydrofuran for ultrasonic dispersion, adding 0.804g of terephthalaldehyde and 0.708g of 2, 4, 6-tris (4-aminophenyl) -1, 3, 5-triazine, heating in a water bath at 70 ℃, stirring for 24 hours, adding 5mL of acetic acid with the concentration of 6mol/L for catalysis, and filtering and drying to obtain the silicon-based composite negative electrode material.
The silicon-based composite negative electrode material prepared in the embodiment is mixed with conductive carbon black, CMC and SBR according to the mass ratio of 16: 2: 1 and evenly coated on the surface of copper foil to prepare the pole piece. And assembling the obtained pole piece, a metal lithium piece counter electrode, LX-025 electrolyte and a Celgard2400 type diaphragm into a button battery, and performing charge and discharge tests on the manufactured button battery. The charging and discharging voltage used in the test process is 0.01-1.5V, and the current density is 300 mA.g < -1 >. The sample test results are shown in table 1.
Example 3
Weighing 5g of silicon-carbon composite powder and 0.05g of single-walled carbon nanotube, putting the silicon-carbon composite powder and the single-walled carbon nanotube into tetrahydrofuran, performing ultrasonic dispersion to assemble the silicon-carbon composite powder and the single-walled carbon nanotube together, adding 0.804g of terephthalaldehyde and 0.708g of 2, 4, 6-tris (4-aminophenyl) -1, 3, 5-triazine, heating in a water bath at 70 ℃, stirring for 24 hours, simultaneously adding 5mL of acetic acid with the concentration of 6mol/L for catalysis, and then filtering and drying to obtain the silicon-based composite negative electrode material.
The silicon-based composite negative electrode material prepared in the embodiment is mixed with conductive carbon black, CMC and SBR according to the mass ratio of 16: 2: 1 and uniformly coated on the surface of copper foil to prepare a pole piece. And assembling the obtained pole piece, a metal lithium piece counter electrode, LX-025 electrolyte and Celgard2400 type diaphragm into a button battery, and carrying out charging and discharging tests on the manufactured button battery. The charging and discharging voltage used in the test process is 0.01-1.5V, and the current density is 300 mA.g -1 . The sample test results are shown in table 1.
Example 4
Weighing 5g of silicon powder and 0.05g of single-walled carbon nanotube, placing the silicon powder and the single-walled carbon nanotube into tetrahydrofuran for ultrasonic dispersion, adding 0.402g of m-phthalaldehyde and 0.2g of 4, 4' -diaminodiphenyl ether, heating in a water bath at 70 ℃, stirring for 48 hours, simultaneously adding 5mL of acetic acid with the concentration of 6mol/L for catalysis, and then filtering and drying to obtain the silicon-based composite negative electrode material.
The silicon-based composite negative electrode material prepared in the embodiment is mixed with conductive carbon black, CMC and SBR according to the mass ratio of 16: 2: 1 and evenly coated on the surface of copper foil to prepare the pole piece. And assembling the obtained pole piece, a metal lithium piece counter electrode, LX-025 electrolyte and a Celgard2400 type diaphragm into a button battery, and performing charge and discharge tests on the manufactured button battery. The charging and discharging voltage used in the test process is 0.01-1.5V, and the current density is 300 mA.g < -1 >. The sample test results are shown in table 1.
Example 5
Weighing 5gSi/SiO X And putting the powder and 0.05g of single-walled carbon nanotube into tetrahydrofuran for ultrasonic dispersion, adding 0.402g of m-phthalaldehyde and 0.2g of 4, 4' -diaminodiphenyl ether, heating in a water bath at 70 ℃, stirring for 48 hours, simultaneously adding 5mL of acetic acid with the concentration of 6mol/L for catalysis, and then filtering and drying to obtain the silicon-based composite negative electrode material.
The silicon-based composite negative electrode material prepared in the embodiment is mixed with conductive carbon black, CMC and SBR according to the mass ratio of 16: 2: 1 and uniformly coated on the surface of copper foil to prepare a pole piece. And assembling the obtained pole piece, a metal lithium piece counter electrode, LX-025 electrolyte and a Celgard2400 type diaphragm into a button battery, and performing charge and discharge tests on the manufactured button battery. The charging and discharging voltage used in the test process is 0.01-1.5V, and the current density is 300 mA.g < -1 >. The sample test results are shown in table 1.
Example 6
Weighing 5g of silicon-carbon composite powder and 0.05g of single-walled carbon nanotube, putting the silicon-carbon composite powder and the single-walled carbon nanotube into tetrahydrofuran for ultrasonic dispersion, adding 0.402g of m-phthalaldehyde and 0.2g of 4, 4' -diaminodiphenyl ether, heating in a water bath at 70 ℃, stirring for 24 hours, simultaneously adding 5mL of acetic acid with the concentration of 6mol/L for catalysis, and then filtering and drying to obtain the silicon-based composite negative electrode material.
The silicon-based composite negative electrode material prepared in the embodiment is mixed with conductive carbon black, CMC and SBR according to the mass ratio of 16: 2: 1 and evenly coated on the surface of copper foil to prepare the pole piece. And assembling the obtained pole piece, a metal lithium piece counter electrode, LX-025 electrolyte and a Celgard2400 type diaphragm into a button battery, and performing charge and discharge tests on the manufactured button battery. The charging and discharging voltage used in the test process is 0.01-1.5V, and the current density is 300 mA-g -1 . The sample test results are shown in table 1.
Example 7
Weighing 5g of silicon powder and 0.05g of single-walled carbon nanotube, putting the silicon powder and the single-walled carbon nanotube into tetrahydrofuran, performing ultrasonic dispersion to assemble the silicon powder and the single-walled carbon nanotube together, adding 0.21g of 4, 4 '-biphenyldicarboxaldehyde and 0.214g of 3, 3' -diaminobenzidine, heating in a water bath at 70 ℃, stirring for 48 hours, simultaneously adding 5mL of acetic acid with the concentration of 6mol/L for catalysis, and then filtering and drying to obtain the silicon-based composite negative electrode material.
The silicon-based composite negative electrode material prepared in the embodiment is mixed with conductive carbon black, CMC and SBR according to the mass ratio of 16: 2: 1 and evenly coated on the surface of copper foil to prepare the pole piece. Assembling the obtained pole piece, a metal lithium piece counter electrode, LX-025 electrolyte and a Celgard2400 type diaphragm into a button battery, and pairingAnd (5) carrying out charge and discharge tests on the manufactured button cell. The charging and discharging voltage used in the test process is 0.01-1.5V, and the current density is 300 mA-g -1 . The sample test results are shown in table 1.
Example 8
Weighing 5gSi/SiO X Putting the powder and 0.05g of single-walled carbon nanotube into tetrahydrofuran, performing ultrasonic dispersion to assemble the two together, adding 0.21g of 4, 4 '-biphenyldicarboxaldehyde and 0.214g of 3, 3' -diaminobenzidine, heating in a water bath at 70 ℃, stirring for 48 hours, simultaneously adding 5mL of acetic acid with the concentration of 6mol/L for catalysis, and then filtering and drying to obtain the silicon-based composite negative electrode material.
The silicon-based composite negative electrode material prepared in the embodiment is mixed with conductive carbon black, CMC and SBR according to the mass ratio of 16: 2: 1 and evenly coated on the surface of copper foil to prepare the pole piece. And assembling the obtained pole piece, a metal lithium piece counter electrode, LX-025 electrolyte and a Celgard2400 type diaphragm into a button battery, and performing charge and discharge tests on the manufactured button battery. The charging and discharging voltage used in the test process is 0.01-1.5V, and the current density is 300 mA.g < -1 >. The sample test results are shown in table 1.
Example 9
Weighing 5g of silicon-carbon composite powder and 0.05g of single-walled carbon nanotube, putting the silicon-carbon composite powder and the single-walled carbon nanotube into tetrahydrofuran for ultrasonic dispersion, adding 0.21g of 4, 4 '-biphenyldicarboxaldehyde and 0.214g of 3, 3' -diaminobenzidine, heating in a water bath at 70 ℃, stirring for 24 hours, simultaneously adding 5mL of acetic acid with the concentration of 6mol/L for catalysis, and then filtering and drying to obtain the silicon-based composite negative electrode material.
The silicon-based composite negative electrode material prepared in the embodiment is mixed with conductive carbon black, CMC and SBR according to the mass ratio of 16: 2: 1 and evenly coated on the surface of copper foil to prepare the pole piece. And assembling the obtained pole piece, a metal lithium piece counter electrode, LX-025 electrolyte and a Celgard2400 type diaphragm into a button battery, and performing charge and discharge tests on the manufactured button battery. The charging and discharging voltage used in the test process is 0.01-1.5V, and the current density is 300 mA-g -1 . The sample test results are shown in table 1.
Comparative example 1
Mixing silicon powder, conductive carbon black, CMC and SBR according to the mass ratio of 16: 2: 1, and uniformly coating the mixture on the surface of copper foil to prepare the pole piece. And assembling the obtained pole piece, a metal lithium piece counter electrode, LX-025 electrolyte and a Celgard2400 type diaphragm into a button battery, and performing charge and discharge tests on the manufactured button battery. The charging and discharging voltage used in the test process is 0.01-1.5V, and the current density is 300 mA.g < -1 >. The sample test results are shown in table 1.
Comparative example 2
According to the mass ratio of 16: 2: 1, mixing Si/SiO X Mixing with conductive carbon black, CMC and SBR, and uniformly coating on the surface of copper foil to obtain the pole piece. And assembling the obtained pole piece, a metal lithium piece counter electrode, LX-025 electrolyte and a Celgard2400 type diaphragm into a button battery, and performing charge and discharge tests on the manufactured button battery. The charging and discharging voltage used in the test process is 0.01-1.5V, and the current density is 300 mA.g < -1 >. The sample test results are shown in table 1.
Comparative example 3
And mixing the silicon-carbon composite powder with conductive carbon black, CMC and SBR according to the mass ratio of 16: 2: 1, and uniformly coating the mixture on the surface of the copper foil to prepare the pole piece. And assembling the obtained pole piece, a metal lithium piece counter electrode, LX-025 electrolyte and a Celgard2400 type diaphragm into a button battery, and performing charge and discharge tests on the manufactured button battery. The charging and discharging voltage used in the test process is 0.01-1.5V, and the current density is 300 mA.g < -1 >. The sample test results are shown in table 1.
TABLE 1 comparison of electrochemical Performance of different samples of examples 1-9 with comparative examples 1-3
Figure BDA0003702211680000081
It can be known from the combination of the above examples 1 to 9 and comparative examples 1 to 3 that the silicon-based composite anode material provided by the invention utilizes Schiff base to wrap the silicon-based material and the one-dimensional carbon nano material to construct an artificial SEI film, thereby ensuring that the artificial SEI film is not cracked in the expansion process. Meanwhile, the method is beneficial to improving the ionic conductivity, inhibiting the growth of Li dendritic crystals and further improving the first reversible capacity, the first coulombic efficiency and the cycling stability of the battery.
The above description is only for the specific embodiment of the present invention, but the protection scope of the present invention is not limited thereto, and it should be understood by those skilled in the art that any changes or substitutions that can be easily conceived by those skilled in the art within the technical scope of the present invention are within the protection scope and the disclosure of the present invention.

Claims (8)

1. A silicon-based composite anode material is characterized in that: the silicon-based composite negative electrode material comprises a silicon-based material, a one-dimensional carbon nano material and Schiff base wrapping the silicon-based material and the one-dimensional carbon nano material.
2. The silicon-based composite anode material according to claim 1, wherein: the silicon-based material comprises a pure silicon material, a silicon carbon material and a silicon oxygen material.
3. The silicon-based composite anode material according to claim 1, wherein: the one-dimensional carbon nano material comprises carbon nano tubes and carbon nano fibers.
4. The silicon-based composite anode material according to claim 1, wherein: the thickness of the Schiff base wrapping the silicon-based material and the one-dimensional carbon nano material is 0.5-50 nm.
5. The silicon-based composite anode material according to claim 1, wherein: the content of the one-dimensional carbon nano material is 0.01-0.3% of the mass of the silicon-based composite negative electrode material, wherein the mass of the silicon-based composite negative electrode material is 100%.
6. The silicon-based composite anode material according to claim 1, wherein: the silicon-based composite negative electrode material comprises, by mass, 100% of a silicon-based composite negative electrode material, and the content ratio of the silicon-based composite negative electrode material to the one-dimensional carbon nano material to the Schiff base is (95-99) to (0.01-0.1) to (0.1-5).
7. A method for preparing a silicon-based composite anode material according to any one of claims 1 to 6, characterized in that:
ultrasonically dispersing a silicon-based material and a one-dimensional carbon nano material in tetrahydrofuran, then adding a material for synthesizing Schiff base, adding 5ml of 6mol/L acetic acid in the process of heating and stirring in a water bath at the temperature of 60-90 ℃, continuously stirring for 12-48h, and then filtering and drying to obtain the silicon-based composite negative electrode material.
8. The method for preparing a silicon-based composite anode material according to claim 7, wherein: the Schiff base is synthesized by one of terephthalaldehyde, m-phthalaldehyde and 4, 4 ' -biphenyldicarboxaldehyde and one of 2, 4, 6-tri (4-aminophenyl) -1, 3, 5-triazine, 4 ' -diaminodiphenyl ether and 3, 3 ' -diaminobenzidine.
CN202210700892.0A 2022-06-20 2022-06-20 Silicon-based composite negative electrode material and preparation method thereof Pending CN115101730A (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
CN202210700892.0A CN115101730A (en) 2022-06-20 2022-06-20 Silicon-based composite negative electrode material and preparation method thereof

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
CN202210700892.0A CN115101730A (en) 2022-06-20 2022-06-20 Silicon-based composite negative electrode material and preparation method thereof

Publications (1)

Publication Number Publication Date
CN115101730A true CN115101730A (en) 2022-09-23

Family

ID=83293510

Family Applications (1)

Application Number Title Priority Date Filing Date
CN202210700892.0A Pending CN115101730A (en) 2022-06-20 2022-06-20 Silicon-based composite negative electrode material and preparation method thereof

Country Status (1)

Country Link
CN (1) CN115101730A (en)

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN116217854A (en) * 2023-03-27 2023-06-06 福州大学 Conjugated microporous polymeric material and application thereof in photoinduction controllable free radical polymerization

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN116217854A (en) * 2023-03-27 2023-06-06 福州大学 Conjugated microporous polymeric material and application thereof in photoinduction controllable free radical polymerization

Similar Documents

Publication Publication Date Title
Xu et al. Tri-functionalized polypropylene separator by rGO/MoO 2 composite for high-performance lithium–sulfur batteries
CN113054165B (en) Negative pole piece of zinc secondary battery and preparation method and application thereof
CN107895779B (en) High-capacity potassium ion battery negative electrode material and preparation method and application thereof
CN110233256B (en) Composite nano material and preparation method thereof
CN110289408A (en) Nano-silicon and silicon/carbon composite and preparation method and application based on cutting scrap silicon
CN111785949B (en) Modified conductive polymer coated silicon-based negative electrode material, and preparation method and application thereof
CN111180714A (en) Carbon/molybdenum dioxide/silicon/carbon composite material, battery cathode comprising same and lithium ion battery
CN115101741B (en) Nitrogen-doped graphene-coated silicon-carbon composite material and preparation method and application thereof
CN112110448A (en) Nitrogen-doped carbon and nano-silicon composite anode material and preparation method thereof
CN112038614B (en) Negative electrode material for sodium ion battery and preparation method thereof
CN112002886A (en) Potassium ion battery negative electrode material metal alloy and preparation method thereof
CN104103808B (en) A kind of lithium ion battery lamellar stannum carbon composite and preparation method thereof
CN112038637A (en) Composite conductive agent, preparation method thereof and lithium ion battery
CN113991089B (en) Sodium ion battery and preparation method thereof
CN111180717A (en) Novel silicon-carbon composite negative electrode material and preparation method thereof
CN108695509B (en) Composite lithium battery positive electrode with high energy storage efficiency, preparation method thereof and lithium battery
CN115101730A (en) Silicon-based composite negative electrode material and preparation method thereof
CN114050226A (en) Negative electrode material and preparation method thereof, negative plate and lithium ion battery
CN110416515B (en) Lithium ion battery, lithium ion battery cathode material and preparation method
CN110970606B (en) Nitrogen-doped hollow spherical carbon-coated sulfur positive electrode material and preparation method and application thereof
WO2023240891A1 (en) Cyano group-modified zr-fe mof, preparation method therefor, and zinc-based flow battery zinc negative electrode material
CN108695496B (en) Graphene-coated porous red phosphorus and conductive carbon composite material, and preparation method and application thereof
WO2022120592A1 (en) Preparation of negative electrode material base on potassium polycarboxylate and graphite composite and use of potassium ion battery
CN115172680A (en) High-capacity high-rate lithium ion battery and preparation method thereof
CN111525107B (en) Novel synthesis method of organic micromolecule coated silicon negative electrode material

Legal Events

Date Code Title Description
PB01 Publication
PB01 Publication
SE01 Entry into force of request for substantive examination
SE01 Entry into force of request for substantive examination