CN114665082A - Negative electrode material and preparation method and application thereof - Google Patents
Negative electrode material and preparation method and application thereof Download PDFInfo
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- 239000007773 negative electrode material Substances 0.000 title claims abstract description 38
- 238000002360 preparation method Methods 0.000 title claims abstract description 24
- OKTJSMMVPCPJKN-UHFFFAOYSA-N Carbon Chemical compound [C] OKTJSMMVPCPJKN-UHFFFAOYSA-N 0.000 claims abstract description 92
- 229910002804 graphite Inorganic materials 0.000 claims abstract description 52
- 239000010439 graphite Substances 0.000 claims abstract description 52
- PSHMSSXLYVAENJ-UHFFFAOYSA-N dilithium;[oxido(oxoboranyloxy)boranyl]oxy-oxoboranyloxyborinate Chemical compound [Li+].[Li+].O=BOB([O-])OB([O-])OB=O PSHMSSXLYVAENJ-UHFFFAOYSA-N 0.000 claims abstract description 37
- 229910021389 graphene Inorganic materials 0.000 claims abstract description 32
- 239000010405 anode material Substances 0.000 claims abstract description 10
- 239000002994 raw material Substances 0.000 claims abstract description 7
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- 229910001416 lithium ion Inorganic materials 0.000 abstract description 34
- HBBGRARXTFLTSG-UHFFFAOYSA-N Lithium ion Chemical compound [Li+] HBBGRARXTFLTSG-UHFFFAOYSA-N 0.000 abstract description 33
- 239000000463 material Substances 0.000 abstract description 13
- 238000012546 transfer Methods 0.000 abstract description 6
- 238000009792 diffusion process Methods 0.000 abstract description 5
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- 229910013458 LiC6 Inorganic materials 0.000 abstract 1
- XKRFYHLGVUSROY-UHFFFAOYSA-N Argon Chemical group [Ar] XKRFYHLGVUSROY-UHFFFAOYSA-N 0.000 description 16
- 238000000576 coating method Methods 0.000 description 16
- 230000000052 comparative effect Effects 0.000 description 14
- 229910052744 lithium Inorganic materials 0.000 description 14
- WHXSMMKQMYFTQS-UHFFFAOYSA-N Lithium Chemical compound [Li] WHXSMMKQMYFTQS-UHFFFAOYSA-N 0.000 description 12
- 239000011248 coating agent Substances 0.000 description 12
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- 229910052786 argon Inorganic materials 0.000 description 8
- 239000010406 cathode material Substances 0.000 description 8
- 229910021393 carbon nanotube Inorganic materials 0.000 description 6
- 239000002041 carbon nanotube Substances 0.000 description 6
- 238000001816 cooling Methods 0.000 description 6
- 230000000694 effects Effects 0.000 description 6
- 238000012216 screening Methods 0.000 description 6
- 238000005245 sintering Methods 0.000 description 6
- 230000014759 maintenance of location Effects 0.000 description 5
- 238000012360 testing method Methods 0.000 description 5
- IJGRMHOSHXDMSA-UHFFFAOYSA-N Atomic nitrogen Chemical compound N#N IJGRMHOSHXDMSA-UHFFFAOYSA-N 0.000 description 4
- 230000004888 barrier function Effects 0.000 description 4
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- KMTRUDSVKNLOMY-UHFFFAOYSA-N Ethylene carbonate Chemical compound O=C1OCCO1 KMTRUDSVKNLOMY-UHFFFAOYSA-N 0.000 description 1
- 229910001290 LiPF6 Inorganic materials 0.000 description 1
- 239000000654 additive Substances 0.000 description 1
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- 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
- H01M4/58—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
- H01M4/62—Selection of inactive substances as ingredients for active masses, e.g. binders, fillers
- H01M4/624—Electric conductive fillers
-
- 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
- H01M4/62—Selection of inactive substances as ingredients for active masses, e.g. binders, fillers
- H01M4/624—Electric conductive fillers
- H01M4/625—Carbon or graphite
-
- 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
Abstract
The invention discloses a negative electrode material and a preparation method and application thereof, and the negative electrode material provided by the invention comprises an inner core and a shell wrapping the surface of the inner core; the preparation raw material of the inner core comprises graphite; the raw materials for preparing the shell comprise graphene and lithium tetraborate. The lithium tetraborate has good lithium ion conductivity, promotes the diffusion transfer efficiency of lithium ions on the surface and the inner layer of the material, improves the lithium ion transfer kinetics, greatly reduces the reaction polarization and improves the multiplying power performance; meanwhile, the graphene with high electronic conductivity rapidly conducts electrons to graphite and cooperates with lithium ions to gradually form LiC6Compound to achieve rapid charging. The invention also provides a preparation method and application of the anode material.
Description
Technical Field
The invention belongs to the technical field of new energy materials, and particularly relates to a negative electrode material and a preparation method and application thereof.
Background
At present, the effective endurance mileage of the new energy automobile is generally short, the number of charging piles is limited, the charging piles are distributed unevenly, the charging time is long, convenience is achieved, and the consumption experience of users is very important, so that the market demand of high-magnification quick charging of the new energy automobile is increasingly urgent.
The graphite has low cost, rich source and low lithium-releasing potential (0.1V)vs.Li/Li+) The first coulombic efficiency is high, the electronic conductivity is high, and the volume expansion rate in the charging and discharging process is only about 10%, so that the negative electrode material in the commercial lithium ion power battery is mainly made of graphite, and in terms of capacity performance, the specific capacity of the commercial graphite negative electrode is close to the theoretical specific capacity (372 mAh/g), the technology is mature, but the graphite serving as the main negative electrode material of the lithium ion battery in a new energy automobile cannot meet the requirement of quick charging. This is because the lithium ion conductivity of the electrolyte is about 10-3S/cm, the lithium ion conductivity in graphite is far lower than that in electrolyte, under the drive of an electric field with high-rate quick charging, lithium ions can quickly penetrate through the electrolyte and concentrate on the surface of a graphite cathode, cannot enter the interior of a graphite material in time, so that local current is concentrated, the local potential of the cathode is reduced to be below 0V, and finally lithium is seriously separated from the surface of the graphite cathode, a small amount of separated lithium metal can be oxidized into lithium ions by galvanic corrosion and then inserted into a graphite layer again, and most of lithium metal generated by lithium separation is stripped into dead lithium, so that how to improve the lithium ion conductivity in the graphite is a key link for solving the problem of quick charging of the graphite. Researches show that graphite has a highly oriented layered structure, graphite layers are usually stacked in a direction parallel to a current collector during coating, and density functional theory calculates that the energy potential barrier of 10.2eV is required to be overcome when lithium ions pass through a six-membered carbon ring, and even if the structure has the defects of Stone-Wales topological defect, single atom vacancy defect, diatomic vacancy defect and the like, the energy potential barrier of 2.36eV is required to be overcome when the lithium ions pass through the six-membered carbon ring; thermodynamic calculations in LiPF6In a mixed EC and DMC electrolyte, which is an electrolyte, the energy barrier overcome by lithium ions entering graphite is about 0.5eV, and therefore the barrier for lithium ions through edge sites is significantly lower than the barrier through six-membered rings. For this reason, by reducing the stoneThe method for realizing quick charge by weakening the anisotropy of the ink by the particle size, shortening the diffusion distance of lithium ions and reducing the migration resistance of the lithium ions is a method for realizing quick charge, but the quick charge effect of the graphite negative electrode obtained by the method is still not obvious.
Therefore, it is a urgent task to develop a negative electrode material capable of solving the problem of slow charging rate of the conventional graphite negative electrode material.
Disclosure of Invention
The present invention is directed to solving at least one of the problems of the prior art described above. According to the invention, lithium tetraborate and graphene are coated on the surface of graphite, and the lithium tetraborate has good lithium ion conduction performance, so that the diffusion transfer efficiency of lithium ions on the surface and the inner layer of the material is promoted, the lithium ion transfer kinetics is improved, the reaction polarization is greatly reduced, and the rate capability is improved. Meanwhile, the graphene with high electronic conductivity can rapidly conduct electrons to graphite and gradually form LiC by matching with lithium ions6Compound to achieve rapid charging.
According to one aspect of the invention, a negative electrode material is provided, which comprises an inner core and an outer shell wrapping the inner core;
the preparation raw material of the inner core comprises graphite;
the shell is prepared from raw materials including graphene and lithium tetraborate.
The negative electrode material disclosed by the invention has at least the following beneficial effects:
if the requirement of quick charge is to be met, the negative electrode material needs to have high lithium ion conductivity and high electronic conductivity. Lithium ion conductivity of lithium tetraborate 10-4S/cm, lithium ion conductivity close to that of the electrolyte, and electronic conductivity of graphene is 106S/cm is two orders of magnitude higher than that of graphite, but the electronic conductivity of lithium tetraborate and the ionic conductivity of graphene are both lower, and the lithium tetraborate can not meet the requirement of quick charging when used alone as a shell. According to the invention, the lithium tetraborate and the graphene are coated on the surface of the graphite, and the lithium tetraborate has good lithium ion conduction performance, so that the lithium ions are promoted to expand on the surface and the inner layer of the materialThe bulk transfer efficiency improves the lithium ion transfer dynamics, greatly reduces the reaction polarization and improves the multiplying power performance. Meanwhile, the graphene with high electronic conductivity can rapidly conduct electrons to graphite and gradually form LiC by matching with lithium ions6Compound to achieve rapid charging.
In some embodiments of the invention, the anode material has a particle size of 33 μm or less.
In some preferred embodiments of the present invention, the D50 of the negative electrode material is 15 μm or more.
The particle size of the cathode material can improve the electrochemical performance and the service life of a power battery or an energy storage battery, and after the graphene and the lithium tetraborate are mixed and coated, the conductivity and the electronic conductivity of lithium ion are improved, the impedance is reduced, and the cycle life is prolonged.
In some embodiments of the invention, the capacity retention rate of the anode material at the 100 th week of (4C/0.1C) is not less than 93.0%.
In some embodiments of the invention, the capacity retention rate of the anode material at 100 weeks (6C/0.1C) is not less than 90.4%.
The second aspect of the present invention provides a preparation method of the above negative electrode material, including the following steps:
s1, mixing the lithium tetraborate, the graphene and the graphite;
s2, carrying out heat treatment on the mixture obtained in the step S1;
in the preparation method provided by the invention, the reactions and mechanisms of the steps are as follows:
the mixing in step S1 is actually dry coating by physical adsorption;
the heat treatment in the step S2 improves the adhesion between the outer shell and the inner core coated by the dry method in the step S1; specifically, the lithium tetraborate melts to perform a bonding function.
The preparation method of the negative electrode material at least has the following beneficial effects:
1. in the production process of the present invention, the dry coating by physical adsorption in step S1 does not generate a component in the casing which is ineffective or adversely affects the coating effect.
2. The coating process is simple, no additional equipment is needed to be purchased and a factory building is arranged when the coating process is implemented on a production line, the three-waste treatment is not involved, and the coating process is easy to implement technically.
In some preferred embodiments of the present invention, the method further comprises sieving the heat-treated mixture obtained in step S2.
The coating process may produce some large particles due to sticking, which are removed by sieving.
In some embodiments of the invention, the lithium tetraborate and graphene are analytically pure grade materials.
In some embodiments of the invention, the mass ratio of the lithium tetraborate to the graphene to the graphite is 0.01 to 0.05: 0.001-0.007: 1.
in some preferred embodiments of the present invention, the mass ratio of the graphene to the graphite is 0.001 to 0.005: 1.
in some preferred embodiments of the present invention, the mass ratio of the graphene to the graphite is: 0.002-0.004: 1.
in some preferred embodiments of the present invention, the mass ratio of the lithium tetraborate to the graphite is 0.03 to 0.04: 1.
in the preparation method provided by the invention, the shell is formed by solid-phase fusion coating, and the coated area is related to the amount of the shell preparation raw material; if the addition amount of the lithium tetraborate is too low, the coating area is too small (discontinuous coating), and the diffusion efficiency of lithium ions in the negative electrode material obtained by the invention is influenced; if the addition amount of lithium tetraborate is too large, a large amount of graphite surface is coated (the thickness is too thick), and meanwhile, the coating of graphene on the graphite surface is reduced, but because the electronic conductivity of lithium tetraborate is low, the excessive coating of lithium tetraborate can influence the electronic conductivity of a negative electrode material formed after coating and influence the charge and discharge performance. In addition, since graphene is a two-dimensional network structure, if excessive graphene is added, diffusion of lithium ions in the coated material is affected, and the barrier for lithium ions to penetrate through the graphene six-membered ring is also high.
In some embodiments of the invention, the mixing is performed in a vertical high efficiency coulter mixer.
In some embodiments of the invention, the vertical high-efficiency coulter mixer has a rotation speed of 30-50 m/s.
In some embodiments of the invention, the mixing time is 12-24 hours.
In some preferred embodiments of the present invention, the mixing time is 17 to 19 hours.
If the mixing time is too short, the mixing is not uniform, which may result in non-uniform coating; if the mixing time is too long, the production efficiency will be affected.
In some embodiments of the present invention, the heating rate of the heat treatment is 4-10 ℃/min.
In some embodiments of the present invention, the temperature of the heat treatment is 1000 to 1200 ℃.
In some preferred embodiments of the present invention, the temperature of the heat treatment is 1100 to 1200 ℃.
If the temperature of the heat treatment is lower than 1000 ℃, lithium tetraborate is difficult to melt, so that the coated negative electrode material is easy to fall off under stress; if the temperature of the heat treatment is higher than 1200 ℃, the energy consumption is increased and the cost is increased.
In some embodiments of the present invention, the heat treatment time is 1 to 6 hours.
In some preferred embodiments of the present invention, the heat treatment time is 3 to 5 hours.
In some preferred embodiments of the present invention, the heat treatment time is 3 to 4 hours.
In some embodiments of the invention, the heat treatment is performed under a protective atmosphere.
In some embodiments of the invention, the protective atmosphere is argon.
The heat treatment process of the present invention uses argon gas for protection because if nitrogen is used, the nitrogen will react with lithium, weakening the coating effect.
The third aspect of the invention provides an application of the negative electrode material in a secondary battery.
In some embodiments of the invention, the secondary battery comprises a lithium ion battery.
Drawings
The invention is further described with reference to the following figures and examples, in which:
FIG. 1 is a scanning electron micrograph of the negative electrode material obtained in example 1 of the present invention.
FIG. 2 is a transmission electron microscope image of the negative electrode material obtained in example 1 of the present invention.
Detailed Description
The concept and technical effects of the present invention will be clearly and completely described below in conjunction with the embodiments to fully understand the objects, features and effects of the present invention. It is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all embodiments, and those skilled in the art can obtain other embodiments without inventive effort based on the embodiments of the present invention, and all embodiments are within the protection scope of the present invention.
Example 1:
the embodiment provides a preparation method of an anode material, which comprises the following specific steps:
mixing lithium tetraborate, graphene and graphite in a vertical high-efficiency coulter mixer at a mass ratio of 3:0.1:100 at a speed of 40m/s for 17 hours, putting the mixture into a tubular sintering furnace, carrying out argon protection at a temperature rise speed of 5 ℃/min, raising the temperature to 1000 ℃, keeping the temperature for 3 hours, naturally cooling the sintered material to 25 ℃, and screening by using a 425-mesh sieve to obtain the qualified graphite cathode material.
The scanning electron microscope image of the negative electrode material obtained in this example is shown in fig. 1, the transmission electron microscope image of the negative electrode material is shown in fig. 2, the shell on the left side of the dotted line is a coating layer, and the graphite with a lamellar structure is on the right side.
Graphite is produced by the new material melted lithium technology limited in Hunan province, and graphene is produced by the new material melted lithium technology limited in Hunan province.
Example 2
The embodiment provides a preparation method of a negative electrode material, which comprises the following specific steps:
mixing lithium tetraborate, graphene and graphite in a vertical high-efficiency coulter mixer at a mass ratio of 3:0.3:100 for 17 hours at a speed of 40m/s, placing the mixture into a tubular sintering furnace, carrying out argon protection at a heating speed of 7 ℃/min, heating to 1200 ℃, carrying out heat preservation for 5 hours, naturally cooling the sintered material to 25 ℃, and screening by using a 425-mesh sieve to obtain the qualified graphite cathode material.
Example 3
The embodiment provides a preparation method of a negative electrode material, which comprises the following specific steps:
mixing lithium tetraborate, graphene and graphite in a vertical high-efficiency coulter mixer according to a mass ratio of 4:0.5:100 at a speed of 40m/s for 17 hours, placing the mixture into a tubular sintering furnace, carrying out argon protection at a heating speed of 10 ℃/min, heating to 1100 ℃, carrying out heat preservation for 3 hours, naturally cooling a sintered material to 25 ℃, and screening by using a 425-mesh sieve to obtain a qualified graphite cathode material.
Comparative example 1
The comparative example provides a preparation method of a negative electrode material, in which the graphene in example 1 is replaced by a carbon nanotube, and the other conditions are the same, and the preparation method specifically comprises the following steps:
mixing lithium tetraborate, carbon nano tubes and graphite in a vertical efficient coulter mixer at a mass ratio of 4:1:100 for 17 hours at a speed of 40m/s, placing the mixture into a tubular sintering furnace, performing argon protection at a heating speed of 5 ℃/min, heating to 1000 ℃, preserving heat for 3 hours, naturally cooling the sintered material to 25 ℃, and screening by using a 425-mesh sieve, wherein the undersize product is the qualified graphite cathode material.
Comparative example 2
The comparative example provides a preparation method of a negative electrode material, wherein the lithium tetraborate in the example 1 is changed into beta-alumina, and the other conditions are the same, and the preparation method comprises the following specific steps:
mixing beta-alumina, graphene and graphite in a vertical high-efficiency coulter mixer according to a mass ratio of 5:0.1:100 at a speed of 40m/s for 17 hours, placing the mixture into a tubular sintering furnace, carrying out argon protection at a temperature rise speed of 5 ℃/min, raising the temperature to 1000 ℃, carrying out heat preservation for 3 hours, naturally cooling the sintered material to 25 ℃, and screening by using a 425-mesh sieve to obtain the qualified graphite cathode material.
Comparative example 3
The comparative example provides a preparation method of a negative electrode material, wherein the lithium tetraborate in example 1 is omitted, the other conditions are the same, and the preparation method comprises the following specific steps:
mixing graphene and graphite in a vertical efficient coulter mixer according to a mass ratio of 0.1:100 at a speed of 40m/s for 17 hours, placing the mixture into a tubular sintering furnace, carrying out argon protection at a heating speed of 5 ℃/min, heating to 1000 ℃, keeping the temperature for 3 hours, naturally cooling the sintered material to 25 ℃, and screening by using a 425-mesh sieve, wherein the undersize is the qualified graphite cathode material.
Test example 1
The test example tests the charge and discharge detection results of the negative electrode materials of examples 1 to 3 and comparative examples 1 to 3, and the test results are shown in table 1, wherein lithium tetrafluoroborate is used as an electrolyte in examples 1 to 3 and comparative examples 1 to 2, the concentration of the electrolyte is 1mol/L, the volume ratio of ethylene carbonate to diethyl carbonate is 1:1, and lithium tetraborate is added as an additive in addition to the conventional electrolyte lithium tetrafluoroborate and is 0.02% of the mass of the electrolyte in comparative example 3; the calculation method for detecting the rate performance and the capacity retention rate by adopting the button cell is the ratio of the gram specific capacity of charge N to the gram specific capacity of charge first week, and the first cycle lithium removal capacity at 4C rate/the first cycle lithium removal capacity at 0.1 rate.
TABLE 1 Charge test results of the negative electrode materials obtained in examples 1 to 3 and comparative examples 1 to 3
As can be seen from table 1, in comparative example 1, the electronic conductivity of the carbon nanotube is close to that of graphite, but the carbon nanotube is a coaxial circular tube made of carbon atoms, the lithium ion conductivity of the carbon nanotube is lower than that of graphene and far lower than that of graphite, in comparative example 2, β -alumina has high hardness and poor compaction effect, and the lithium ion conductivity of the carbon nanotube is lower than that of lithium tetraborate, so that the capacity retention rate of the graphite anode material coated by mixing lithium tetraborate and graphene is far higher than that of comparative examples 1-2. And because the solubility of lithium tetraborate is very low, even if the electrolyte added with lithium tetraborate is adopted in comparative example 3, the capacity retention rate is lower than that of the graphite negative electrode material coated by lithium tetraborate and graphene. The cathode material prepared by the method has more excellent rate capability, and can better meet the requirements of new energy automobiles on power lithium batteries.
The technical solutions of the present invention have been described in detail with reference to the embodiments, but the present invention is not limited to the embodiments, and various changes can be made within the knowledge of those skilled in the art without departing from the spirit of the present invention. The embodiments of the invention and the features of the embodiments can be combined with each other without conflict.
Claims (10)
1. The negative electrode material is characterized by comprising an inner core and an outer shell wrapping the inner core;
the preparation raw material of the inner core comprises graphite;
the shell is prepared from raw materials including graphene and lithium tetraborate.
2. The negative electrode material of claim 1, wherein the negative electrode material has a particle size of 33 μm or less.
3. The method for preparing the anode material according to claim 1 or 2, comprising the steps of:
s1, mixing the lithium tetraborate, the graphene and the graphite;
s2, carrying out heat treatment on the mixture obtained in the step S1.
4. The preparation method of the negative electrode material according to claim 3, wherein the mass ratio of the lithium tetraborate to the graphene to the graphite is 0.01-0.05: 0.001-0.007: 1.
5. the method for preparing the negative electrode material of claim 4, wherein the mass ratio of the lithium tetraborate to the graphite is 0.03-0.04: 1.
6. the method for preparing the negative electrode material according to claim 3, wherein the temperature rise rate of the heat treatment is 4-10 ℃/min.
7. The method for preparing the negative electrode material according to claim 3, wherein the temperature of the heat treatment is 1000 to 1200 ℃.
8. The preparation method of the anode material according to claim 3, wherein the heat treatment time is 1-6 h.
9. The method for producing the anode material according to claim 3, wherein the heat treatment is performed in a protective atmosphere.
10. Use of the anode material according to claim 1 or 2 in a secondary battery.
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| CN115321526A (en) * | 2022-08-24 | 2022-11-11 | 湖南镕锂新材料科技有限公司 | Preparation method and application of graphene precursor slurry |
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