CN114212770B - Modified hard carbon material, preparation method thereof, electrode and application - Google Patents

Modified hard carbon material, preparation method thereof, electrode and application Download PDF

Info

Publication number
CN114212770B
CN114212770B CN202111683674.2A CN202111683674A CN114212770B CN 114212770 B CN114212770 B CN 114212770B CN 202111683674 A CN202111683674 A CN 202111683674A CN 114212770 B CN114212770 B CN 114212770B
Authority
CN
China
Prior art keywords
hard carbon
carbon material
reaction
temperature
modified hard
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.)
Active
Application number
CN202111683674.2A
Other languages
Chinese (zh)
Other versions
CN114212770A (en
Inventor
陈兵帅
张秀云
潘福森
范拯华
王晓阳
胡国志
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.)
Shanghai Shanshan Technology Co Ltd
Original Assignee
Shanghai Shanshan Technology Co Ltd
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 Shanghai Shanshan Technology Co Ltd filed Critical Shanghai Shanshan Technology Co Ltd
Priority to CN202111683674.2A priority Critical patent/CN114212770B/en
Publication of CN114212770A publication Critical patent/CN114212770A/en
Application granted granted Critical
Publication of CN114212770B publication Critical patent/CN114212770B/en
Active legal-status Critical Current
Anticipated expiration legal-status Critical

Links

Images

Classifications

    • C—CHEMISTRY; METALLURGY
    • C01—INORGANIC CHEMISTRY
    • C01B—NON-METALLIC ELEMENTS; COMPOUNDS THEREOF; METALLOIDS OR COMPOUNDS THEREOF NOT COVERED BY SUBCLASS C01C
    • C01B32/00—Carbon; Compounds thereof
    • C01B32/05—Preparation or purification of carbon not covered by groups C01B32/15, C01B32/20, C01B32/25, C01B32/30
    • 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
    • H01M4/13—Electrodes for accumulators with non-aqueous electrolyte, e.g. for lithium-accumulators; Processes of manufacture thereof
    • H01M4/133—Electrodes based on 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
    • H01M4/13—Electrodes for accumulators with non-aqueous electrolyte, e.g. for lithium-accumulators; Processes of manufacture thereof
    • H01M4/139—Processes of manufacture
    • H01M4/1393—Processes of manufacture of electrodes based on carbonaceous material, e.g. graphite-intercalation compounds or CFx
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02E—REDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGY GENERATION, TRANSMISSION OR DISTRIBUTION
    • Y02E60/00—Enabling technologies; Technologies with a potential or indirect contribution to GHG emissions mitigation
    • Y02E60/10—Energy storage using batteries

Abstract

The invention discloses a modified hard carbon material, a preparation method thereof, an electrode and application. The preparation method of the modified hard carbon material comprises the following steps: (1) Mixing asphalt and a catalyst, and preparing a hard carbon precursor through oxidation reaction; the mass ratio of the catalyst to the asphalt is (0.01-0.2): 1; (2) And (3) dispersing and kneading the hard carbon precursor and the nano material, then carrying out a curing reaction or a bonding reaction, and then carrying out heat treatment. The modified hard carbon material prepared by the invention has small specific surface area, high tap density and low resistivity, and the lithium ion battery prepared by the modified hard carbon material serving as the negative electrode material can maintain high first charge capacity, and meanwhile, the first coulombic efficiency is improved and the multiplying power performance is good.

Description

Modified hard carbon material, preparation method thereof, electrode and application
Technical Field
The invention relates to a modified hard carbon material, a preparation method thereof, an electrode and application.
Background
In recent years, lithium ion batteries iterate rapidly. Due to the self reasons of graphite materials, the novel negative electrode material is rapidly promoted, and the hard carbon material serving as the negative electrode material has good interlayer spacing and pores, so that lithium ions can be greatly embedded into the material, and the material has high energy density, charge-discharge performance and low-temperature performance and is accepted by the market. Due to the shortage of lithium resources, the sodium ion battery becomes the next research hot spot, the popularization and the use of hard carbon are accelerated, and the problem of lithium resource shortage is solved to a certain extent.
The existing hard carbon material for the lithium battery has the problems of large specific surface area and low initial coulomb efficiency, and is particularly obvious in the sodium ion battery. An amorphous carbon negative electrode material is prepared in Chinese patent document CN 112531160A. The amorphous carbon negative electrode material is characterized in that a precursor obtained by the meridian combination reaction of carbon particles is inlaid in a foam carbon skeleton, the surface of the amorphous carbon negative electrode material comprises macropores and ultra-micropores, the specific surface area of the amorphous carbon negative electrode material is large, and the formed composite material has anti-adsorptivity, but the initial coulombic efficiency is low.
Therefore, how to prepare a hard carbon material with small specific surface and high initial coulomb efficiency, which can be applied to a negative electrode material, is a technical problem to be solved in the field.
Disclosure of Invention
The invention aims to overcome the defects of large specific surface and low first coulomb efficiency of a hard carbon material in the prior art, and provides a modified hard carbon material, a preparation method, an electrode and application thereof. The modified hard carbon material provided by the invention has the characteristics of small specific surface area, high tap density and low resistivity, and the battery prepared from the modified hard carbon material provided by the invention can improve the first coulomb efficiency while maintaining high first charge capacity, and has good multiplying power performance and quick charge performance. The invention adopts a unique hard carbon preparation process, has simple process and environment-friendly operation without pollution.
The invention solves the technical problems through the following technical scheme.
The invention provides a preparation method of a modified hard carbon material, which comprises the following steps:
(1) Mixing asphalt and a catalyst, and preparing a hard carbon precursor through oxidation reaction; the mass ratio of the catalyst to the asphalt is (0.01-0.2): 1;
(2) And (3) dispersing and kneading the hard carbon precursor and the nano material, then carrying out a curing reaction or a bonding reaction, and then carrying out heat treatment.
In step (1), the mass ratio of the catalyst to the pitch is preferably (0.02-0.15): 1, e.g. 0.0225:1, 0.03:1, 0.044:1 or 0.05:1.
In step (1), the pitch may be one or more of coal tar pitch, petroleum pitch, natural pitch and wood pitch, for example petroleum pitch.
In step (1), the softening point of the bitumen may be conventional in the art, preferably from 120 to 300 ℃, more preferably from 180 to 280 ℃, for example 200 ℃, 250 ℃ or 280 ℃.
In step (1), the pitch may have a particle size of 2 to 20. Mu.m, preferably 4 to 12. Mu.m, for example 8. Mu.m.
In the step (1), before the mixing, the asphalt may be subjected to a pretreatment operation of crushing.
Wherein the equipment used for the pulverization may be roll mill, mechanical mill, air mill or cryogenic mill, such as air mill.
In step (1), the catalyst may be a catalyst having a pore-forming effect, preferably one or more of metal oxides, metal sulfides, metal chlorides, sulfates and phosphates.
Wherein the metal oxide is preferably one or more of aluminum oxide, magnesium oxide, titanium oxide and zinc oxide.
Wherein the metal sulfide is preferably one or more of zinc sulfide, calcium sulfide and magnesium sulfide, such as magnesium sulfide.
Wherein the metal chloride is preferably one or more of mercury chloride, copper chloride and aluminum chloride, such as aluminum chloride.
Wherein the sulfate is preferably calcium sulfate.
In step (1), the equipment used for mixing may be a VC blender, a semi-finished blender or a wire rod blender, such as a VC blender.
In step (1), the temperature of the oxidation reaction may be conventional in the art, preferably from 100 to 600 ℃, more preferably from 180 to 400 ℃, for example 360 ℃ or 400 ℃.
In the step (1), the temperature of the oxidation reaction can be reached by means of constant temperature, continuous temperature rise or temperature rise-constant temperature interval in the oxidation reaction process.
When a continuous heating is employed, the heating rate may be conventional in the art, preferably 1-10deg.C/min, preferably 2-5deg.C/min, such as 2deg.C/min or 3deg.C/min. The slower heating rate can remove asphalt volatile matters completely, and the influence on the subsequent process is avoided.
In step (1), the time of the oxidation reaction may be conventional in the art, preferably 0.5 to 8 hours, more preferably 1 to 4 hours, for example 2 hours or 4 hours.
In the step (1), the atmosphere of the oxidation reaction may be an air atmosphere, an ammonia atmosphere, an oxygen atmosphere or an ozone atmosphere, for example, an air atmosphere or an oxygen atmosphere.
In the step (1), the gas flow rate during the oxidation reaction may be conventional in the art, and is preferably 0.01 to 10L/(kg. Min), more preferably 0.5 to 2.5L/(kg. Min), for example 1.5L/(kg. Min) or 2L/(kg. Min).
In step (1), the equipment used in the oxidation reaction may be an electrically heated mixer, a muffle furnace, a resistance furnace, a tube furnace, a roller kiln, or a roller furnace, such as a muffle furnace.
In the step (1), after the oxidation reaction is finished, the method can further comprise post-treatment operations of cooling and crushing.
Wherein the temperature after the temperature reduction can be room temperature, and can be 20-25 ℃ generally.
Wherein the equipment used for the pulverization may be roll mill, mechanical mill, air mill or cryogenic mill, such as air mill.
In step (2), the mass ratio of the hard carbon precursor to the nanomaterial may be 1 (0.01-0.3), preferably 1 (0.01-0.2), such as 1:0.1, 1:0.15, or 1:0.175.
In step (2), the hard carbon precursor may have a particle size of 6-10 μm, for example 6 μm or 8 μm.
In the step (2), the nanomaterial may be one or more of a carbonate, a silica, graphene, a carbon nanotube, a nano alumina, a Prussian blue nanoparticle, a polystyrene nanoparticle, and a polyglyceryl methacrylate nanoparticle, for example, a carbon nanotube, a polyglyceryl methacrylate nanoparticle, or graphene. The nanomaterial may fill small holes or micropores in the hard carbon precursor.
In the step (2), the dispersion kneading may be performed by using a kneader, a planetary dispersion mixer, a conical twin screw mixer or a horizontal ribbon heating mixer, for example, a kneader or a horizontal ribbon heating mixer.
In the step (2), the linear velocity during the dispersion kneading may be 1 to 10m/s, for example, 1m/s, 5m/s or 8m/s.
In step (2), the time of the dispersion kneading may be 0.5 to 3 hours, for example, 0.5 hours, 1 hour or 2 hours.
In step (2), the curing agent used in the curing reaction may be one or more of conventional in the art, preferably resol, epoxy, amino, acrylic, sodium carboxymethyl cellulose (CMC), synthetic resin, rubber, cyanoacrylate-polyethylene glycol, cyanoacrylate-acetylated hydroxypropyl cellulose, emulsion and latex, such as acrylic, sodium carboxymethyl cellulose (CMC) or latex.
In step (2), the binder used in the bonding reaction may be conventional in the art, preferably an emulsion and/or a latex, such as a latex.
In step (2), the mass ratio of the hard carbon precursor to the curing agent in the curing reaction may be 1 (0.01-0.2), preferably 1 (0.01-0.15), for example 1:0.05, 1:0.0625 or 1:0.1.
In step (2), the mass ratio of the hard carbon precursor to the binder in the bonding reaction may be 1 (0.01-0.2), preferably 1 (0.01-0.15), for example 1:0.1125.
In step (2), the linear velocity during the curing reaction or the bonding reaction may be 2 to 6m/s, for example 2m/s or 5m/s.
In step (2), the curing reaction or bonding reaction may be carried out for a period of time ranging from 0.5 to 3 hours, for example 0.5 hours, 1 hour or 2 hours.
In step (2), the holding temperature during the heat treatment may be conventional in the art, preferably 600-1400 ℃, more preferably 800-1100 ℃, for example 1000 ℃.
In step (2), the rate of heating during the heat treatment may be conventional in the art, preferably 1-10deg.C/min, more preferably 2-5deg.C/min, such as 2deg.C/min, 3deg.C/min or 5deg.C/min.
In step (2), the incubation time during the heat treatment may be conventional in the art, preferably 1 to 12 hours, more preferably 1 to 6 hours, for example 4 hours or 6 hours.
In the step (2), the heat treatment may adopt a step-wise temperature raising method, and the step-wise temperature raising method may include the following steps: heating rate of 2-3 ℃/min to 200-400 ℃, constant temperature of 30-60min,2-3 ℃/min to 500-700 ℃, constant temperature of 30-60min,2-3 ℃/min to 900-1100 ℃ and constant temperature for 4-6h;
or, the step-up heating mode may include the following steps: the temperature rising rate is 3-6 ℃/min to 900-1100 ℃, and the constant temperature is 4-6 hours.
In a preferred embodiment, the step-wise heating method includes the following steps: heating rate of 2 ℃/min to 200 ℃, constant temperature of 30min,2 ℃/min to 600 ℃, constant temperature of 30min,3 ℃/min to 1000 ℃ and constant temperature for 4h.
In another preferred embodiment, the step-wise heating mode includes the following steps: heating rate of 2 ℃/min to 400 ℃, constant temperature of 60min,3 ℃/min to 600 ℃, constant temperature of 60min,2 ℃/min to 1000 ℃ and constant temperature of 6h.
In another preferred embodiment, the step-wise heating mode includes the following steps: heating rate is 5 ℃/min to 1000 ℃, and the temperature is kept for 4 hours.
In the step (2), the atmosphere of the heat treatment may be a gas which does not participate in the reaction of the system, and may be nitrogen, such as nitrogen or argon, without being limited to an inert gas.
In step (2), the equipment used for the heat treatment may be conventional in the art, such as a vacuum furnace.
In the step (2), after the heat treatment reaction is finished, the method can further comprise a cooling operation.
Wherein the temperature after the temperature reduction can be room temperature, and can be 20-25 ℃ generally.
The invention also provides a modified hard carbon material, which is prepared by the preparation method of the modified hard carbon material.
The invention also provides an electrode comprising a modified hard carbon material as described above.
The invention also provides an application of the modified hard carbon material as the anode material or the electrode in a battery.
In the present invention, the battery may be a lithium ion battery, a sodium ion battery, or a solid state battery.
On the basis of conforming to the common knowledge in the field, the above preferred conditions can be arbitrarily combined to obtain the preferred examples of the invention.
The reagents and materials used in the present invention are commercially available.
The invention has the positive progress effects that:
1. the invention carries out catalytic oxidation on asphalt to form hard carbon precursor, then disperses and kneads the hard carbon precursor with nano material, and obtains modified hard carbon material through curing reaction or bonding reaction and heat treatment. In the modified hard carbon material prepared by the invention, the large holes are more, the micropores are filled, the capability of rapid intercalation and deintercalation of lithium ions can be promoted, and the modified hard carbon material has small specific surface area (can be less than or equal to 2.3 m) 2 High tap density (0.9-1.1 g/cm) 3 ) The SEI film has the characteristics of low resistivity (lower than 0.20Ω & cm under 10 MPa), more lithium ions can react after the SEI film is formed, and the prepared modified hard carbon material has good wettability with electrolyte, thereby reducing the diffusion resistance of lithium ions.
2. When the modified hard carbon material prepared by the invention is used as a cathode material for preparing a battery, the first charge capacity is higher than 490.2mAh/g, the first coulomb efficiency of the first charge capacity is higher than 88%, the highest coulomb efficiency is 91.2%, and the 3C rapid discharge constant current ratio is higher than 53%.
3. The preparation method of the modified hard carbon material is simple in operation, green, pollution-free, easy to control, safe, reliable, environment-friendly, wide in selection equipment, wide in raw material selection range, capable of performing industrial production and low in cost.
Drawings
FIG. 1 is an XRD pattern of the modified hard carbon material obtained in example 1.
FIG. 2 is an SEM image of the modified hard carbon material obtained in example 1.
Detailed Description
The invention is further illustrated by means of the following examples, which are not intended to limit the scope of the invention. The experimental methods, in which specific conditions are not noted in the following examples, were selected according to conventional methods and conditions, or according to the commercial specifications.
The reagents and the raw materials adopted by the invention are all commercial products.
In the present invention, steps and methods not described in detail can be described with reference to conventional methods or related equipment in the industry.
Example 1
1.5 kg of petroleum asphalt with a softening point of 200 ℃ is subjected to jet milling and crushing, and the particle size of the crushed asphalt is 8 mu m. Taking 2kg of prepared asphalt, adding 60g of aluminum chloride, and placing a sample into a VC mixer for mixing. And (3) discharging, putting the material into a muffle furnace for oxidization, wherein an air atmosphere is selected, the gas flow is 2L/(kg.min), and the heating rate is 3 ℃/min. Heating to 360 ℃, and constant-temperature oxidation time is 2h. And cooling to room temperature, and crushing the oxidized and discharged material by using an jet mill crusher to obtain hard carbon precursors with the particle size of 8 mu m.
2. And (3) dispersing, kneading and curing the hard carbon precursor with the particle size of 8 mu m, which is prepared according to the step (1), the carbon nano tube and the acrylic resin. 800g of hard carbon precursor with the particle size of 8 mu m is taken and placed in a kneader, 80g of carbon nano tube is added, and then dispersed and kneaded, wherein the linear speed of a turntable is 5m/s, and the kneading is carried out for 30min. After the materials are uniformly mixed, 40g of acrylic resin is added for curing, a kneader is started, the linear speed of a turntable is 2m/s, and the curing is carried out for 30min.
3. And (3) carrying out carbonization heat treatment on the material prepared in the step (2), carrying out a vacuum furnace and a nitrogen atmosphere, wherein the heating rate adopts stage heating, the constant temperature is 30min from 2 ℃/min to 200 ℃, the constant temperature is 30min from 2 ℃/min to 600 ℃, the constant temperature is 30min from 3 ℃/min to 1000 ℃, the constant temperature is 4h, and discharging after cooling to room temperature, thus obtaining the modified hard carbon material.
Example 2
1. The asphalt in example 1 was replaced with asphalt having a softening point of 250℃and 2kg of the prepared asphalt was taken, 100g of magnesium sulfide was added, and the mixture was oxidized at a heating rate of 3℃per minute as in example 1. Heating to 400 ℃, and constant-temperature oxidation time is 4h. And cooling to room temperature, and crushing the oxidized and discharged material by using an jet mill crusher to obtain hard carbon precursors with the particle size of 8 mu m.
2. And (3) dispersing, kneading and curing the hard carbon precursor with the particle size of 8 mu m, which is prepared according to the step (1), the carbon nano tube and the acrylic resin. 800g of hard carbon precursor with the particle size of 8 mu m is taken, 120g of carbon nano tube is added into a horizontal spiral ribbon heating mixer, and the linear speed is 1m/s, and the dispersion is carried out for 1h. After the materials are uniformly mixed, 50g of acrylic resin is added for curing, the linear speed is 2m/s, and the curing is carried out for 30min.
3. And 2, carrying out carbonization heat treatment on the material prepared in the step 2, wherein equipment and gas atmosphere are the same as those in the embodiment 1, the temperature rising rate adopts stage temperature rising, the temperature is between 2 ℃/min and 400 ℃, the temperature is kept for 60min, the temperature is between 3 ℃/min and 600 ℃, the temperature is kept for 60min, the temperature is between 2 ℃/min and 1000 ℃, the temperature is kept for 6h, and the modified hard carbon material is obtained after cooling to the room temperature.
Example 3
1. The asphalt and equipment used were the same as in example 1, 2kg of the asphalt obtained was mixed with 45g of calcium sulfate. And (3) discharging for oxidation, wherein an oxygen atmosphere is selected, the gas flow is 1.5L/(kg.min), and the heating rate is 2 ℃/min. Heating to 360 ℃, and constant-temperature oxidation time is 4h. Cooling to room temperature, and pulverizing to obtain hard carbon precursor with particle size of 8 μm.
2. And (3) dispersing, kneading and curing the hard carbon precursor with the particle size of 8 mu m, which is prepared according to the step (1), the carbon nano tube and the acrylic resin. The apparatus was as in example 1, and 800g of hard carbon precursor having a particle diameter of 8 μm was added to 140g of polyglyceryl methacrylate nanobeads, followed by dispersion kneading at a turntable linear speed of 8m/s in a kneader for 30 minutes. After the materials are uniformly mixed, 80g of sodium carboxymethylcellulose (CMC) is added for curing, a kneader is started, and the linear speed of a turntable is 5m/s for curing for 1h.
3. And (3) carrying out carbonization heat treatment on the material prepared in the step (2), carrying out heat treatment in the same way as in the example (1), and discharging after cooling to room temperature to obtain the modified hard carbon material.
Example 4
1.5 kg of petroleum asphalt with a softening point of 280 ℃ is subjected to small air flow grinding and crushing, and the particle size of the crushed asphalt is 6 mu m. 2kg of the asphalt obtained was mixed with 88g of aluminum chloride, and the mixture was carried out in the same manner as in example 1. The oxidation conditions were the same as in example 1, and the resultant was discharged and pulverized to obtain a hard carbon precursor having a particle diameter of 6. Mu.m.
2. And (3) dispersing, kneading and solidifying the hard carbon precursor with the particle size of 6 mu m, which is prepared according to the step (1), graphene and latex. Taking 800g of hard carbon precursor with the particle size of 6 mu m, adding 120g of graphene into a kneader, performing dispersion kneading, and adding 90g of latex for bonding after uniformly mixing the materials. Dispersing and bonding are carried out at the linear speed of the turntable of 5m/s for 2 hours.
3. And (3) carrying out carbonization heat treatment on the material prepared in the step (2), carrying out a vacuum furnace and a nitrogen atmosphere, keeping the temperature for 4 hours at a heating rate of 5 ℃/min to 1000 ℃, and discharging after cooling to room temperature to obtain the modified hard carbon material.
Comparative example 1
1.5 kg of petroleum asphalt with a softening point of 200 ℃ is subjected to small air flow grinding and crushing, and the particle size of the crushed asphalt is 8 mu m. 2kg of the asphalt obtained was taken and no catalyst was added, and the conditions of the oxidation equipment were the same as in example 1. And (3) crushing the oxidized discharge material by using an jet mill crusher to obtain hard carbon precursors with the particle size of 8 mu m.
2. The hard carbon precursor with the particle size of 8 mu m prepared according to the step 1 and the carbon nano tube are dispersed, kneaded, solidified and bonded, and the experimental scheme is the same as that of the example 1.
3. And (3) carrying out carbonization heat treatment on the material prepared in the step (2), cooling the heat treatment equipment to room temperature under the same conditions as in the example (1), and discharging to obtain the contrast hard carbon material.
Comparative example 2
1. A hard carbon precursor having a particle diameter of 8 μm was prepared in the same manner as in example 1.
2. And (3) dispersing and kneading the hard carbon precursor with the particle size of 8 mu m prepared in the step (1) and the carbon nano tube. 800g of hard carbon precursor with the particle size of 8 μm was taken without adding a curing agent, and 100g of carbon nanotubes were added in a kneader to carry out dispersion kneading.
3. And (3) carrying out carbonization heat treatment on the material prepared in the step (2), cooling the heat treatment equipment to room temperature under the same conditions as in the example (1), and discharging to obtain the contrast hard carbon material.
Comparative example 3
1. A hard carbon precursor having a particle diameter of 8 μm was prepared in the same manner as in comparative example 1.
2. And (2) carrying out curing and bonding on the hard carbon precursor with the particle size of 8 mu m prepared in the step (1) and a curing agent, taking 800g of the hard carbon precursor with the particle size of 8 mu m, and adding 80g of acrylic resin into a kneader to carry out curing and bonding.
3. And (3) carrying out carbonization heat treatment on the material prepared in the step (2), cooling the heat treatment equipment to room temperature under the same conditions as in the example (1), and discharging to obtain the contrast hard carbon material.
Effect example 1 morphology and Structure of modified hard carbon Material
The modified hard carbon materials prepared in examples 1 to 4 and comparative examples 1 to 3 were subjected to performance test by a method conventional in the art, and the test results are shown in fig. 1, 2 and table 1.
The particle size distribution was determined using a Mastersize 2000 laser particle size analyzer and D50 was calculated and the test results are shown in table 1.
The material was subjected to phase testing by XRD diffractometer (X' Pert3 Powder) in a scanning manner of theta-2 theta, a step of 2 DEG/s, and FIG. 1 is an XRD pattern of the modified hard carbon material obtained in example 1. The spectrum was analyzed, and the modified hard carbon material prepared in example 1 was a standard hard carbon structure.
The microstructure was characterized by zeissegiminsem 500 field emission scanning electron microscopy, and fig. 2 is an SEM image of the modified hard carbon material prepared in example 1. The modified hard carbon material prepared in the embodiment 1 has uniform particle morphology and smooth surface, and is beneficial to the rapid movement of lithium ions.
Effect example 2 conductivity and electrochemical Properties
(1) Resistivity test
The modified hard carbon materials prepared in examples 1 to 4 and comparative examples 1 to 3 were subjected to resistivity test at 10MPa using ST2722-SZ equipment.
(2) Preparation of electrodes
The modified hard carbon materials prepared in examples 1-4 and comparative examples 1-3 are respectively mixed with acetylene black conductive agent and PVDF according to the mass ratio of 85:2:13 under the condition of room temperature, NMP is used as solvent to prepare uniform slurry, the slurry is uniformly coated on copper foil, and then the copper foil is put into a vacuum drying oven to be dried for 12 hours at 100 ℃. Cutting the dried copper foil into 2cm in area 2 The wafer of (2) is made into a working electrode.
(3) Assembly of button cell
Under the room temperature condition, taking a metal lithium sheet as a negative electrode and a counter electrode, taking the product obtained in the step (1) as a working electrode, taking a Celgard2400 polypropylene porous membrane as a diaphragm, and taking 1mol/L LiPF 6 /EC:DECThe solution (volume ratio is 1:1) is taken as electrolyte, and the CR-2032 button cell is assembled in a vacuum glove box and tightly sealed mechanically. The assembled cell was allowed to stand at room temperature for 24 hours and then electrochemical testing was started.
(4) Electrochemical testing
The assembled cell was allowed to stand at room temperature for 24 hours and then electrochemical testing was started. On an Arbin battery test system, the current of 0.1C is adopted in the first week of test, and the charging and discharging voltage interval is 5 mV-1.5V. And (5) standing for 5 minutes after the charge or discharge is finished. The button cell 3C rapid discharge constant current ratio test adopts a button cell after 3 weeks of 0.1C circulation, wherein 0.1C is firstly charged to 2V, then 3C is firstly discharged to 5mV to obtain capacity a, and then 0.1C is discharged to 5mV to obtain capacity b.3C rapid discharge constant current ratio=a/(a+b) ×100%.
The modified hard carbon materials prepared in examples 1 to 4 and comparative examples 1 to 3 were tested for particle diameter, tap density, specific surface area and resistivity, and first charge capacity, first coulombic efficiency and 3C fast discharge constant current ratio of lithium ion batteries, and the test results are shown in table 1.
TABLE 1
Figure BDA0003444685220000111
As can be seen from Table 1, the modified hard carbon materials prepared in examples 1 to 4 of the present invention, combined with the particle size, show that the specific surface area, tap density and resistivity of the modified hard carbon materials are all superior to those of comparative examples 1 to 3, and the specific surface area is reduced to be less than or equal to 2.3m 2 Per gram, the tap density can reach 0.9-1.1g/cm 3 The resistivity (at 10 MPa) may be lower than 0.20Ω·cm. Examples 1-4 lithium ion batteries prepared again from modified hard carbon materials prepared by filling small holes with a nanomaterial by increasing the pore diameter of the material through a catalyst and oxidation reaction, and combining with a curing agent or a binder have high first charge capacity, high first coulombic efficiency and high 3C fast discharge constant current ratio, and the first charge capacity can be higher than 490.2mAh/g, the first coulombic efficiency can be higher than 88%, the highest can be 91.2%, and the 3C fast discharge constant current ratio can be higher thanGreater than 53%.

Claims (21)

1. The preparation method of the modified hard carbon material is characterized by comprising the following steps:
(1) Mixing asphalt and a catalyst, and preparing a hard carbon precursor through oxidation reaction; the mass ratio of the catalyst to the asphalt is (0.01-0.2): 1; the catalyst is metal sulfide, metal chloride or sulfate; the temperature of the oxidation reaction is 360-600 ℃; the time of the oxidation reaction is 2-8h;
wherein the metal sulfide is one or more of zinc sulfide, calcium sulfide and magnesium sulfide; the metal chloride is one or more of mercury chloride, copper chloride and aluminum chloride; the sulfate is calcium sulfate;
(2) Dispersing and kneading the hard carbon precursor and the nano material, then carrying out a curing reaction or a bonding reaction, and then carrying out heat treatment; the nano material is graphene, a carbon nano tube, prussian blue nano particles, polystyrene nano microspheres or polymethacrylate nano microspheres;
wherein, in the curing reaction, the curing agent is one or more of resol, epoxy resin, amino resin, acrylic resin, sodium carboxymethyl cellulose, rubber, cyanoacrylate-polyethylene glycol and cyanoacrylate-acetylated hydroxypropyl cellulose; in the bonding reaction, the adopted bonding agent is emulsion and/or latex;
in the heat treatment process, the heat preservation temperature is 600-1400 ℃ and the heat preservation time is 1-12h.
2. The method for preparing a modified hard carbon material according to claim 1, wherein the pitch is one or more of coal tar pitch, petroleum pitch, natural pitch and wood pitch;
and/or, in the step (1), the softening point of the asphalt is 120-300 ℃;
and/or, in the step (1), the particle size of the asphalt is 2-20 μm;
and/or, in the step (2), the particle size of the hard carbon precursor is 6-10 mu m;
and/or in the step (2), the nanomaterial is carbon nanotubes, polyglyceryl methacrylate nanospheres or graphene.
3. The method for producing a modified hard carbon material according to claim 2, wherein the asphalt is petroleum asphalt;
and/or, in the step (1), the softening point of the asphalt is 180-280 ℃;
and/or, in the step (1), the particle size of the asphalt is 4-12 μm;
and/or, in the step (1), the metal sulfide is magnesium sulfide;
and/or, in the step (1), the metal chloride is aluminum chloride;
and/or, in step (2), the hard carbon precursor has a particle size of 6 μm or 8 μm;
and/or in the step (2), the curing agent adopted in the curing reaction is acrylic resin or sodium carboxymethyl cellulose;
and/or in the step (2), the adhesive adopted in the bonding reaction is latex.
4. The method for producing a modified hard carbon material as defined in claim 3, wherein in the step (1), the asphalt has a softening point of 200 ℃, 250 ℃ or 280 ℃;
and/or, in the step (1), the particle size of the asphalt is 8 μm.
5. The method for producing a modified hard carbon material according to claim 1, wherein in the step (1), the mass ratio of the catalyst to the pitch is (0.02-0.15): 1;
and/or in the step (2), the mass ratio of the hard carbon precursor to the nano material is 1 (0.01-0.3);
and/or, in the step (2), in the curing reaction, the mass ratio of the hard carbon precursor to the curing agent is 1 (0.01-0.2);
and/or in the step (2), in the bonding reaction, the mass ratio of the hard carbon precursor to the binder is 1 (0.01-0.2).
6. The method of producing a modified hard carbon material according to claim 5, wherein in the step (1), the mass ratio of the catalyst to the pitch in the step (1) is 0.0225:1, 0.03:1, 0.044:1 or 0.05:1;
and/or in the step (2), the mass ratio of the hard carbon precursor to the nano material is 1 (0.01-0.2);
and/or in the step (2), in the curing reaction, the mass ratio of the hard carbon precursor to the curing agent is 1 (0.01-0.15);
and/or in the step (2), in the bonding reaction, the mass ratio of the hard carbon precursor to the binder is 1 (0.01-0.15).
7. The method of claim 6, wherein in step (2), the mass ratio of the hard carbon precursor to the nanomaterial is 1:0.1, 1:0.15, or 1:0.175;
and/or, in the step (2), in the curing reaction, the mass ratio of the hard carbon precursor to the curing agent is 1:0.05, 1:0.0625 or 1:0.1;
and/or in the step (2), in the bonding reaction, the mass ratio of the hard carbon precursor to the binder is 1:0.1125.
8. The method for producing a modified hard carbon material according to claim 1, wherein in the step (1), the temperature of the oxidation reaction is 360 ℃ or 400 ℃;
and/or in the step (1), the temperature of the oxidation reaction is reached by means of constant temperature, continuous temperature rise or temperature rise-constant temperature interval in the oxidation reaction process; when adopting a continuous heating mode, the heating rate is 1-10 ℃/min;
and/or, in the step (1), the time of the oxidation reaction is 2 hours or 4 hours;
and/or, in the step (1), the atmosphere of the oxidation reaction is an air atmosphere, an ammonia gas atmosphere, an oxygen gas atmosphere or an ozone atmosphere;
and/or, in the step (1), the gas flow rate is 0.01-10L/(kg.min) in the oxidation reaction process.
9. The method for producing a modified hard carbon material according to claim 8, wherein in the step (1), when a continuous temperature rising manner is adopted in the oxidation reaction, the temperature rising rate is 2 to 5 ℃/min;
and/or, in the step (1), the atmosphere of the oxidation reaction is an air atmosphere or an oxygen atmosphere;
and/or, in the step (1), the gas flow rate is 0.5-2.5L/(kg.min) in the oxidation reaction process.
10. The method for producing a modified hard carbon material according to claim 9, wherein in the step (1), when a continuous temperature rising manner is adopted during the oxidation reaction, the temperature rising rate is 2 ℃/min or 3 ℃/min;
and/or, in the step (1), the gas flow rate during the oxidation reaction is 1.5L/(kg-min) or 2L/(kg-min).
11. The method for producing a modified hard carbon material according to claim 1, wherein in the step (2), a linear velocity is 1 to 10m/s during the dispersion kneading;
and/or, in the step (2), the time of the dispersion kneading is 0.5 to 3 hours;
and/or, in the step (2), the linear speed is 2-6m/s in the process of the curing reaction or the bonding reaction;
and/or, in the step (2), the time of the curing reaction or the bonding reaction is 0.5-3h;
and/or, in the step (2), in the heat treatment process, the heating rate is 1-10 ℃/min;
and/or, in the step (2), the heat treatment adopts a step-by-step heating mode;
and/or, in the step (2), the atmosphere of the heat treatment is nitrogen or argon.
12. The method for producing a modified hard carbon material as defined in claim 11, wherein in the step (2), the linear velocity is 1m/s, 5m/s or 8m/s during the dispersion kneading;
and/or, in the step (2), the time of the dispersion kneading is 0.5h, 1h or 2h;
and/or, in the step (2), the linear velocity is 2m/s or 5m/s in the curing reaction or the bonding reaction;
and/or, in the step (2), the time of the curing reaction or the bonding reaction is 0.5h, 1h or 2h;
and/or, in the step (2), the heat preservation temperature is 800-1100 ℃ in the heat treatment process;
and/or, in the step (2), in the heat treatment process, the heating rate is 2-5 ℃/min;
and/or, in the step (2), the heat preservation time is 1-6h in the heat treatment process.
13. The method for producing a modified hard carbon material according to claim 12, wherein in the step (2), the heat-retaining temperature is 1000 ℃ during the heat treatment;
and/or, in the step (2), in the heat treatment process, the heating rate is 2 ℃/min, 3 ℃/min or 5 ℃/min;
and/or, in the step (2), the heat preservation time is 4 hours or 6 hours in the heat treatment process.
14. The method for producing a modified hard carbon material as defined in any one of claims 11 to 13, wherein in the step (2), the stepwise temperature rising means comprises the steps of: heating rate of 2-3 ℃/min to 200-400 ℃, constant temperature of 30-60min,2-3 ℃/min to 500-700 ℃, constant temperature of 30-60min,2-3 ℃/min to 900-1100 ℃ and constant temperature for 4-6h;
and/or, in the step (2), the step-wise heating mode comprises the following steps: the temperature rising rate is 3-6 ℃/min to 900-1100 ℃, and the constant temperature is 4-6 hours.
15. The method for preparing a modified hard carbon material according to claim 14, wherein in the step (2), the step of heating comprises the steps of: heating rate of 2 ℃/min to 200 ℃, constant temperature of 30min,2 ℃/min to 600 ℃, constant temperature of 30min,3 ℃/min to 1000 ℃ and constant temperature for 4h; or heating rate of 2 ℃/min to 400 ℃, keeping constant temperature of 60min,3 ℃/min to 600 ℃, keeping constant temperature of 60min,2 ℃/min to 1000 ℃ and keeping constant temperature for 6h;
and/or, in the step (2), the step-wise heating mode comprises the following steps: heating rate is 5 ℃/min to 1000 ℃, and the temperature is kept for 4 hours.
16. The method of producing a modified hard carbon material according to claim 1, wherein in the step (1), the asphalt is further subjected to a pretreatment operation of pulverization before the mixing;
and/or, in the step (1), after the oxidation reaction is finished, the method further comprises the post-treatment operation of cooling and crushing;
and/or, in the step (2), after the heat treatment reaction is finished, the method further comprises the operation of cooling.
17. The method for producing a modified hard carbon material according to claim 16, wherein in the step (1), the temperature after the temperature reduction is 20 to 25 ℃;
and/or, in the step (2), the temperature after cooling is 20-25 ℃.
18. A modified hard carbon material produced by the method for producing a modified hard carbon material according to any one of claims 1 to 17.
19. An electrode comprising the modified hard carbon material of claim 18.
20. Use of the modified hard carbon material of claim 18 as a negative electrode material or the electrode of claim 19 in a battery.
21. Use of the electrode according to claim 19 in a battery, wherein the battery is a lithium ion battery, a sodium ion battery or a solid state battery.
CN202111683674.2A 2021-12-29 2021-12-29 Modified hard carbon material, preparation method thereof, electrode and application Active CN114212770B (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
CN202111683674.2A CN114212770B (en) 2021-12-29 2021-12-29 Modified hard carbon material, preparation method thereof, electrode and application

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
CN202111683674.2A CN114212770B (en) 2021-12-29 2021-12-29 Modified hard carbon material, preparation method thereof, electrode and application

Publications (2)

Publication Number Publication Date
CN114212770A CN114212770A (en) 2022-03-22
CN114212770B true CN114212770B (en) 2023-05-05

Family

ID=80707661

Family Applications (1)

Application Number Title Priority Date Filing Date
CN202111683674.2A Active CN114212770B (en) 2021-12-29 2021-12-29 Modified hard carbon material, preparation method thereof, electrode and application

Country Status (1)

Country Link
CN (1) CN114212770B (en)

Citations (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US20120077020A1 (en) * 2009-05-26 2012-03-29 Kazuo Muramatsu Carbon material and method for producing same
CN105977490A (en) * 2016-05-18 2016-09-28 河南田园新能源科技有限公司 Method for preparing graphene composite negative electrode material from modified graphene oxide

Family Cites Families (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN101887966B (en) * 2010-06-18 2012-12-05 深圳市贝特瑞新能源材料股份有限公司 Preparation method of composite hard carbon cathode material of lithium ion battery
KR20130030769A (en) * 2010-06-18 2013-03-27 비티알 뉴 에너지 머티리얼즈 인코포레이티드 Composite hard carbon material of negative electrode for lithium ion battery and method for preparing the same
CN103199254B (en) * 2013-04-03 2016-08-10 深圳市贝特瑞新能源材料股份有限公司 A kind of graphite negative material of lithium ion battery and preparation method thereof
CN106981629A (en) * 2016-01-16 2017-07-25 山东玉皇新能源科技有限公司 A kind of preparation of lithium-ion-power cell hard carbon cathode material and its method of modifying
CN108963253B (en) * 2018-09-18 2020-07-17 杭州致德新材料有限公司 Porous hard carbon negative electrode material, preparation method thereof and lithium ion battery
CN113800496A (en) * 2021-08-06 2021-12-17 深圳市德方纳米科技股份有限公司 Hard carbon material and preparation method and application thereof

Patent Citations (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US20120077020A1 (en) * 2009-05-26 2012-03-29 Kazuo Muramatsu Carbon material and method for producing same
CN105977490A (en) * 2016-05-18 2016-09-28 河南田园新能源科技有限公司 Method for preparing graphene composite negative electrode material from modified graphene oxide

Also Published As

Publication number Publication date
CN114212770A (en) 2022-03-22

Similar Documents

Publication Publication Date Title
WO2022121136A1 (en) Artificial graphite negative electrode material for high-rate lithium ion battery and preparation method therefor
CN109524648B (en) Porous carbon nanofiber flexible battery material containing nano-silicon and preparation method thereof
CN111653738B (en) Silicon-carbon negative electrode material of lithium ion battery and preparation method thereof
CN113213470A (en) Artificial graphite secondary particle, coating agent, preparation method and application thereof
CN108417813A (en) A kind of preparation method of lithium ion battery negative material
CN112768691B (en) Coating agent, coating modified graphite negative electrode material, preparation method and application thereof, and lithium ion battery
CN112758911B (en) Hard carbon material, preparation method and application thereof, and lithium ion battery
CN111653739B (en) Method for preparing high-cycle-performance SiO negative electrode material of lithium battery
CN106410177A (en) Ellipsoidal SiOx/graphite cathode composite material and preparation method and application thereof
CN112652753A (en) Lithium ion battery negative electrode material, lithium ion battery and preparation method and application thereof
CN113206249A (en) Lithium battery silicon-oxygen composite negative electrode material with good electrochemical performance and preparation method thereof
CN113233451A (en) Modified artificial graphite material, preparation method and application thereof, and lithium ion battery
CN112661133A (en) Preparation method of hard carbon material
CN109860580B (en) Positive electrode material, preparation method thereof, positive plate and lithium-sulfur battery
CN114388755A (en) Silicon-carbon negative electrode material of lithium ion battery and preparation method thereof
CN109638231B (en) Silicon monoxide composite negative electrode material, preparation method thereof and lithium ion battery
CN110970599B (en) Graphene-based composite negative electrode material, preparation method thereof and lithium ion battery
CN114212770B (en) Modified hard carbon material, preparation method thereof, electrode and application
CN112670460A (en) Silicon-carbon composite material, electrode, lithium ion battery and preparation method and application thereof
CN110723721A (en) Method for preparing silicon-carbon negative electrode material of lithium battery, negative electrode material and lithium battery
CN113506862B (en) Nano carbon fiber composite material for lithium-sulfur battery anode and preparation method and application thereof
CN112713277B (en) Hard carbon material, preparation method and application thereof, and lithium ion battery
CN111725512B (en) Porous silicon-carbon composite material of lithium ion battery and preparation method and application thereof
CN114203979A (en) Graphite negative electrode material and preparation method and application thereof
CN112701288A (en) Coated modified graphite material, preparation method and application thereof, and lithium ion battery

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
GR01 Patent grant
GR01 Patent grant