CN112018386B - Artificial graphite material, composite material, preparation method of composite material and lithium ion secondary battery - Google Patents
Artificial graphite material, composite material, preparation method of composite material and lithium ion secondary battery Download PDFInfo
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- CN112018386B CN112018386B CN201910467031.0A CN201910467031A CN112018386B CN 112018386 B CN112018386 B CN 112018386B CN 201910467031 A CN201910467031 A CN 201910467031A CN 112018386 B CN112018386 B CN 112018386B
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- 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
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- H—ELECTRICITY
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- 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
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- 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
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- Y02E60/10—Energy storage using batteries
Abstract
The invention discloses an artificial graphite material, a composite material, a preparation method of the artificial graphite material and the composite material, and a lithium ion secondary battery. The artificial graphite material is prepared by the following method: carrying out temperature programming treatment and graphitization treatment on the raw materials; the raw materials are petroleum green coke particles or a mixture of calcined coke particles and asphalt particles; in the petroleum green coke or the mixture of the calcined coke particles and the asphalt particles, the mass percentage of volatile components is 5-15%; in the temperature programming treatment, when the temperature is more than or equal to 200 ℃ and less than 500 ℃, the temperature rising rate is less than or equal to 2 ℃/min. The artificial graphite particles are compact in interior, few in gaps, high in compaction density and discharge capacity, small in volume expansion in the charge-discharge cycle process and good in cycle performance; the further prepared composite graphite material combines the advantages of high first-efficiency artificial graphite material, good cycle performance and high natural graphite capacity, and can meet the requirement of high energy density of the battery cathode.
Description
Technical Field
The invention relates to the field of lithium battery negative electrode materials, in particular to an artificial graphite material, a composite material, a preparation method of the artificial graphite material and a lithium ion secondary battery.
Background
The lithium ion battery has the advantages of high specific energy, no memory effect, high working voltage, safety, long service life and good cycle performance, and is widely applied to electric automobiles, electronic equipment and energy storage equipment. With the gradual improvement of living standard of substances and the acceleration of rhythm of working life, the endurance requirement of people on electronic products is higher and higher, so that batteries with higher capacity and longer service life are needed to meet the requirements of people.
The lithium ion battery mainly comprises four parts, namely a positive electrode, a negative electrode, a diaphragm and electrolyte, wherein the negative electrode material of the battery has a large influence on the capacity of the battery, so that the development of the negative electrode material with high specific capacity and good cycle performance is the premise of improving the capacity and cycle life of the lithium battery.
CN 103855395A carries out high-temperature pretreatment on spherical natural graphite, then petroleum asphalt and a graphitization catalyst are added, carbonization treatment is carried out after uniform mixing, high-temperature graphitization is carried out after cooling, the obtained material is graded, and the high-capacity natural graphite cathode material is prepared. The material retains the characteristic of high capacity of natural graphite. However, the preparation process needs carbonization, graphitization and grading at last, the preparation process is long, the process is complex, the yield is low, and the prepared natural graphite particles are single particles, so that the cycle expansion is large, and the service life of the battery can be influenced in the using process. CN 1691374A discloses an artificial graphite material coated with asphalt, which has good cycle performance but low capacity of 335mAh/g, and low pole piece compaction density, and can not meet the requirement of high energy density of the current battery.
Therefore, how to prepare a negative electrode material with high discharge capacity, high compaction density and high capacity retention rate is a technical problem to be solved in the field.
Disclosure of Invention
The invention aims to overcome the defect that the discharge capacity of a negative electrode material and the capacity retention rate in the circulation process cannot be simultaneously kept at a higher level (the discharge capacity is more than or equal to 350mAh/g, and the capacity retention rate is more than or equal to 90%) in the prior art, and provides an artificial graphite material, a composite material, a preparation method of the artificial graphite material and the composite material, and a lithium ion secondary battery. The discharge capacity of the artificial graphite material is more than or equal to 350mAh/g, the first efficiency is more than or equal to 93 percent, the 1C/1C circulation 500-week capacity efficiency is more than or equal to 89 percent, and the 3C/0.2C capacity retention rate percent is more than or equal to 75 percent. The composite graphite material prepared by compounding the artificial graphite material and the natural graphite material has the advantages that the discharge capacity, the compaction density, the rate capability, the cycle performance and the like are obviously improved.
The invention provides a preparation method of an artificial graphite material, which comprises the following steps:
carrying out temperature programming treatment and graphitization treatment on the raw materials;
the raw materials are petroleum green coke particles or a mixture of calcined coke particles and asphalt particles; in the petroleum green coke or the mixture of the calcined coke particles and the asphalt particles, the mass percentage of volatile components is 5-15%;
the temperature programming treatment comprises the following steps: the end point temperature of the temperature programming treatment is more than or equal to 500 ℃; in the temperature programming treatment, when the temperature is more than or equal to 200 ℃ and less than 500 ℃, the temperature rising rate is less than or equal to 2 ℃/min.
In the invention, the petroleum green coke particles can be prepared by adopting the conventional process in the field, for example, the petroleum green coke is crushed by jaw and mechanically crushed.
The petroleum green coke can be conventional petroleum green coke in the field, and generally refers to a product which is formed by separating light oil from heavy oil through distillation and then converting the heavy oil through a thermal cracking process and is not calcined. The petroleum green coke may be purchased from Mitsubishi chemical corporation.
In the present invention, the D50 particle size of the petroleum green coke particles may be in the range of D50 particle size as is conventional in the art, for example, 5 to 30 μm, preferably 5 to 15 μm, more preferably 9.0 μm, 9.4 μm, 10 μm or 11 μm.
In the present invention, the mass percentage of volatile components in the petroleum green coke particles is preferably 10 to 15%, for example 11.50% or 12.7%.
In the present invention, the calcined coke particles can be prepared by a conventional process in the art, for example, by jaw crushing and mechanical crushing of calcined coke.
Wherein the calcined coke can be calcined coke which is conventional in the field, and is generally obtained by calcining the petroleum green coke. The temperature of the calcination may be 1000-1500 ℃. The calcined coke is available from Mitsubishi chemical corporation.
In the present invention, the D50 particle size of the calcined coke particles may be in the range of D50 particle size as is conventional in the art, for example, 5 to 30 μm, preferably 5 to 15 μm, more preferably 9.0 μm, 9.4 μm, 10 μm or 11 μm.
In the present invention, the mass percentage of volatile components in the calcined coke particles is preferably 0.1 to 5%, for example, 1.8%.
In the present invention, the D50 particle size of the asphalt particles may be in the range of D50 particle size as is conventional in the art, for example, 1 to 20 μm, preferably 1 to 10 μm, and more preferably 5 μm.
In the invention, the asphalt is preferably asphalt with a softening point of more than or equal to 250 ℃ and a coking value of more than or equal to 75%. The coking value of the bitumen is preferably ≥ 80%, for example 84.4%.
In the present invention, the "mixture of calcined coke particles and asphalt particles" preferably contains 10 to 15% by mass of volatile matter, for example, 11.5%.
In the present invention, the mass ratio of the calcined coke particles to the asphalt particles is preferably (20-30):1, for example, 22: 1.
When the mass ratio of the calcined coke particles to the asphalt particles is 22:1, the mass percentage of volatile components in the calcined coke particles is preferably 1.8%, and the coking value of the asphalt is preferably 84.4%.
In the present invention, the coking value of the asphalt generally refers to the mass percentage of the accumulated coke block formed after the volatile component is separated out from the asphalt under the condition of high temperature (for example 1500 ℃) and oxygen deficiency.
In the invention, the volatile component can be a volatile component which is conventional in the field, and generally refers to a small molecular substance with a boiling point less than or equal to 800 ℃ in the raw material. The content of the volatile components can generally be determined by the following method: heating the raw materials at 850 + -20 deg.C for 7 min under air-isolated condition to reduce the weight, i.e. volatile content.
In the present invention, in the temperature programming treatment, when the temperature is less than 200 ℃, the temperature raising rate is preferably 0.29 to 5.83 ℃/min, for example, 1.83 ℃/min, 1.98 ℃/min or 2.92 ℃/min.
In the present invention, in the temperature programming treatment, when the temperature is 200 ℃ or higher and less than 500 ℃, the temperature raising rate is preferably 0.17 to 2.00 ℃/min, for example, 0.83 ℃/min, 1 ℃/min, 1.11 ℃/min, 1.67 ℃/min, 1.83 ℃/min or 1.98 ℃/min.
In the present invention, in the temperature programming treatment, when the temperature is not less than 200 ℃ and less than 300 ℃, the temperature raising rate is preferably 1.11 to 1.98 ℃/min, for example, 1.11 ℃/min, 1.83 ℃/min or 1.98 ℃/min.
In the present invention, in the temperature programming treatment, when the temperature is equal to or higher than 300 ℃ and lower than 500 ℃, the temperature raising rate is preferably 0.83 to 1.98 ℃/min, for example, 0.83 ℃/min, 1 ℃/min, 1.67 ℃/min or 1.98 ℃/min.
In the invention, in the temperature programming treatment, when the temperature is more than or equal to 500 ℃, constant temperature treatment can be carried out. The duration of the isothermal treatment may be from 1 to 10 hours, for example from 1 to 4 hours, for example again from 2 hours.
In the present invention, the temperature-programmed treatment is preferably: firstly, the temperature is less than 200 ℃, and the temperature is 0.29-5.83 ℃/min; ② the temperature is more than or equal to 200 ℃ and less than 300 ℃, and the temperature is 1.11-1.98 ℃/min; ③ the temperature is less than or equal to 300 ℃ and less than 500 ℃, and the temperature is 0.83-1.98 ℃/min; fourthly, keeping the temperature at 500 ℃ for 1 to 10 hours. More preferably: firstly, the temperature is less than 200 ℃, and 2.92 ℃/min; ② the temperature is more than or equal to 200 ℃ and less than 300 ℃, and the temperature is 1.11 ℃/min; ③ the temperature is less than or equal to 300 ℃ and less than or equal to 500 ℃, 1.67 ℃/min; fourthly, keeping the temperature at 500 ℃ for 1 to 4 hours.
In the present invention, the temperature-programmed treatment may be performed in a drum furnace.
Wherein, when feeding, the rotating speed of the roller furnace can be 5-50Hz, such as 15 Hz.
Wherein, when the temperature programming treatment is carried out, the rotating speed of the roller furnace can be 5-50Hz, such as 25 Hz.
In the invention, after the temperature programming treatment is finished, the graphitization treatment can be carried out after the temperature is cooled to normal temperature by a fan according to the conventional operation in the field. The normal temperature is generally 25 ℃.
In the present invention, the graphitization treatment may be a graphitization treatment that is conventional in the art, for example, in an atmosphere of chlorine at 2800-.
Wherein the temperature of the graphitization treatment is preferably 3000-3200 ℃, for example 3100 ℃.
The invention also provides the artificial graphite material prepared by the method.
The invention also provides an artificial graphite material, which comprises single particles and secondary particles, wherein the single particles are monomer particles with the D50 particle size of 10-20 mu m, the secondary particles are formed by agglomerating primary particles with the D50 particle size of 1-9 mu m, and the D50 particle size of the secondary particles is 10-20 mu m;
the mass ratio of the single particles to the particles is (1-2.33): 1.
In the present invention, the D50 particle size of the single particles is preferably 15-16 μm, for example 15 μm, 15.4 μm or 15.2 μm.
In the present invention, the D50 particle size of the primary particles is preferably 5 to 7 μm, for example 6.0 μm, 5.8 μm or 6.5 μm.
In the present invention, the D50 particle size of the secondary particles is preferably 12 to 15 μm, for example 13 μm, 14.6 μm or 13.8 μm.
In the present invention, the mass ratio of the single particles to the secondary particles is preferably (1-1.5):1, for example, 1.5:1, 1: 1.
In the present invention, the particle size of D50 of the artificial graphite material may be a particle size conventional in the art, and is preferably 15.0-20.0. mu.m, such as 15.0. mu.m, 15.5. mu.m, 15.6. mu.m, 16.4. mu.m, 15.3. mu.m, 15.7. mu.m, 15.8. mu.m, 15.6. mu.m, or 17.0. mu.m.
In the invention, the discharge capacity of the artificial graphite material is more than or equal to 350mAh/g, such as 354.6mAh/g, 357.2mAh/g, 352.3mAh/g, 350.4mAh/g, 350.2mAh/g, 353.7mAh/g, 352.6mAh/g, 354.3mAh/g, 357.8mAh/g or 353.2 mAh/g.
In the invention, the first efficiency of the artificial graphite material is more than or equal to 94 percent, such as 94.5 percent, 94.7 percent, 93.8 percent, 93.4 percent, 94.2 percent, 94.6 percent, 94.5 percent, 94.2 percent or 93.9 percent.
The invention also provides application of the artificial graphite material as a battery negative electrode material.
The invention also provides a composite graphite material, which comprises the following raw materials: the artificial graphite material and the natural graphite material;
the weight ratio of the artificial graphite material to the natural graphite material is more than or equal to 0.43: 1.
In the present invention, the natural graphite material may be a natural graphite material that is conventional in the art, for example, a natural graphite material prepared by the following method: the spherical natural graphite particles are coated and carbonized.
Wherein the spherical natural graphite particles may have a D50 particle size of 10-50 μm, such as 15-20 μm, and further such as 16.0 μm or 17.0 μm.
Wherein, the coating can be performed according to the conventional operation in the field, for example, the spherical natural graphite particles and the coating agent are mixed and coated.
The coating agent may be one or more of coating agents conventional in the art, such as petroleum asphalt, coal asphalt, and polymer resins. The high molecular resin can be phenolic resin and/or epoxy resin. The petroleum asphalt is preferably petroleum asphalt with a softening point of more than or equal to 250 ℃ and a coking value of more than or equal to 75%.
The particle size of the coating agent may be conventional in the art, for example the particle size of D50 is 1-10 μm, for example 5 μm.
The ratio of the spherical natural graphite particles to the coating agent may be a ratio conventional in the art, and preferably the mass ratio of the spherical natural graphite particles to the coating agent is (2.5-20):1, for example, 19: 1.
The mixing may be carried out in a manner conventional in the art, for example in a conical blender. The rotational speed of the conical blender may be 10-50Hz, for example 20 Hz.
The mixing time may be 0.5-1h, e.g. 45 min.
Wherein the carbonization can be performed according to the conventional operation in the field, such as: increasing the temperature from 25 ℃ to 1300 ℃ in an inert atmosphere for 0.5-24h (e.g., 10 h); keeping the temperature of 1300 ℃ for 1-10h (for example 8 h).
The particle size of the natural graphite material D50 may be as conventional in the art, and is preferably 15.0-20.0 μm, for example 16.5 μm or 17.3 μm.
Wherein the discharge capacity of the natural graphite material is more than or equal to 360mAh/g, such as 368.8mAh/g, 367.6mAh/g or 369.7 mAh/g.
Wherein the first efficiency of the natural graphite material is more than or equal to 93 percent, such as 94.30 percent, 93.80 percent or 93.50 percent.
In the present invention, the weight ratio of the artificial graphite material to the natural graphite material is preferably (0.43-4):1, such as (1-2.33):1 or 4:1, and more preferably 7:3 or 1: 1.
In the present invention, the particle size of the D50 particle of the composite graphite material may be of a size conventional in the art, preferably in the range of 15.0-20.0 μm, for example 15.8 μm or 16.8 μm.
In the invention, the discharge capacity of the composite graphite material is more than or equal to 355mAh/g, such as 358.0mAh/g or 363.5 mAh/g.
In the invention, the first efficiency of the composite graphite material is more than or equal to 94 percent, such as 94.1 percent or 94.4 percent.
The invention also provides a preparation method of the composite graphite material, which comprises the following steps of mixing the artificial graphite material and the natural graphite material.
Wherein the artificial graphite material and the natural graphite material may be mixed in a conical blender. The mixing time may be 45 min. The rotating speed of the conical mixer can be 20 Hz.
The invention also provides application of the composite graphite material as a battery negative electrode material.
The invention also provides a lithium ion secondary battery, and the negative electrode material of the lithium ion secondary battery is the artificial graphite material or the composite graphite material.
On the basis of the common knowledge in the field, the above preferred conditions can be combined randomly to obtain the preferred embodiments of the invention.
The reagents and starting materials used in the present invention are commercially available.
The positive progress effects of the invention are as follows:
(1) the artificial graphite particles are prepared by adopting petroleum coke as a raw material through temperature programming treatment and high-temperature graphitization, and have the advantages of compact interior, fewer gaps, higher compaction density and discharge capacity, small volume expansion in the charge-discharge cycle process and good cycle performance; specifically, the method comprises the following steps: the discharge capacity is more than or equal to 350mAh/g, the first efficiency is more than or equal to 93 percent, the 1C/1C circulation 500-week capacity efficiency is more than or equal to 89 percent, the 3C/0.2C capacity retention rate is more than or equal to 75 percent, and the discharge capacity, the rate capability, the circulation performance and the like are obviously improved.
(2) According to the invention, the artificial graphite material and the natural graphite are mixed to obtain the composite graphite material, the composite graphite material has high capacity and good compaction performance, and the advantages of high first efficiency, good cycle performance and high capacity of the natural graphite of the artificial graphite material are combined, so that the composite material has the advantages of high capacity and good compaction performance, and meets the requirement of high energy density of the battery cathode.
(3) The composite graphite material disclosed by the invention is simple in preparation process, low in cost and short in preparation period, combines the advantages of artificial graphite and natural graphite, has high energy density, is easy to produce in mass production, and can be applied to cylindrical and square aluminum shell batteries.
Drawings
Fig. 1 is a Scanning Electron Microscope (SEM) image of composite graphite particles prepared in example 1.
Fig. 2 is a button cell charge-discharge curve diagram of the composite graphite particles prepared in example 1.
Detailed Description
The invention is further illustrated by the following examples, which are not intended to limit the scope of the invention. The experimental methods without specifying specific conditions in the following examples were selected according to the conventional methods and conditions, or according to the commercial instructions.
In the following examples:
the oil-based green coke particles are purchased from Mitsubishi chemical corporation, and have a volatile content of 10-15%;
the spherical natural graphite is purchased from Qingdao Guangxing electronic materials Co Ltd;
the petroleum asphalt is purchased from German Lutcoge chemical company, the softening point is more than or equal to 250 ℃, and the coking value is more than or equal to 75 percent;
the oil-based calcined coke particles are purchased from Mitsubishi chemical corporation, and have a volatile content of 0.1-5%;
epoxy resins were purchased from Mitsubishi chemical corporation and had a volatile content of 20%.
Example 1
(1) Taking 220kg of oil-based green coke particles (the volatile component is 12.7%) with the particle size D50 of 10 mu m after jaw crushing and mechanical crushing, putting the particles into a roller furnace, adjusting the rotating speed of the roller furnace to be 15Hz, feeding while rotating, adjusting the rotating speed to be 25Hz after the feeding is finished, heating in the furnace, and heating up according to the following procedures: 25 ℃ to 200 ℃ for 1 hour (the heating rate is 2.92 ℃/min); 200 ℃ to 300 ℃ for 1.5 hours (the heating rate is 1.11 ℃/min); 300 ℃ to 500 ℃ for 2 hours (the heating rate is 1.67 ℃/min); keeping the temperature at 500 ℃ for 2 hours, cooling to 25 ℃ after cooling by a fan, and discharging. Then carrying out catalytic graphitization treatment at 2800 ℃ and 3200 ℃ under chlorine gas. Artificial graphite particles (D5015.0 μm) were obtained without crushing, and had a discharge capacity of 354.6mAh/g and a first efficiency of 94.7%.
The artificial graphite particles prepared in the step comprise single particles and secondary particles, wherein the single particles are monomer particles with the diameter of D5015.0 mu m, the secondary particles are formed by agglomerating primary particles with the diameter of D506.0 mu m, the D50 of the secondary particles is 13.0 mu m, and the mass ratio of the single particles to the secondary particles is 1.5: 1.
(2) 95kg of spherical natural graphite (D5017.0 mu m) and 5kg of petroleum asphalt (D505 mu m, the softening point is more than or equal to 250 ℃) are put into a conical mixer for mixing for 45min, and then the materials are discharged. Then carrying out carbonization treatment at 1300 ℃ in a nitrogen atmosphere, wherein the carbonization process comprises the following steps: keeping the temperature of the mixture at 25-1300 ℃ for 10 hours, keeping the temperature of the mixture at 1300 ℃ for 8 hours, then cooling and discharging. The natural graphite particles (D5017.3 mu m) are prepared without crushing, the discharge capacity is 368.8mAh/g, and the first efficiency is 94.3%.
(3) And (3) putting 70kg of the artificial graphite particles in the step (1) and 30kg of the natural graphite particles in the step (2) into a conical mixer, mixing for 45min, and discharging. The composite graphite particles (D5015.8 μm) were obtained without crushing, and had a discharge capacity of 358.0mAh/g and a first efficiency of 94.4%.
Example 2
(1) 200kg of oil-based calcined coke particles (with the volatile component of 1.8%) with the particle size D50 of 11 mu m after jaw crushing and mechanical crushing are mixed with 10kg of petroleum asphalt (with the coking value of 84.4%) with the particle size D505 mu m (in the mixture of the calcined coke particles and the asphalt particles, the mass percent of the volatile component is 11.5%), the rotating speed of a roller furnace is adjusted to 15Hz, the feeding is carried out while rotating, the rotating speed is adjusted to 25Hz after the feeding is finished, the heating in the furnace is started, and the temperature rising program is as follows: 25 ℃ to 200 ℃ for 1 hour (the heating rate is 2.92 ℃/min); 200 ℃ to 300 ℃ for 1.5 hours (the heating rate is 1.11 ℃/min); 300 ℃ to 500 ℃ for 2 hours (the heating rate is 1.67 ℃/min); the temperature is kept constant at 500 ℃ for 2 hours. Cooling to normal temperature after cooling by a fan, and discharging. Then carrying out catalytic graphitization treatment at 3100 ℃ under chlorine gas. Artificial graphite particles (D5017.0 μm) were obtained without crushing, having a discharge capacity of 357.2mAh/g and a first efficiency of 94.5%.
The artificial graphite particles prepared in the step comprise single particles and secondary particles, wherein the single particles are monomer particles with the diameter of D5015.4 mu m, the secondary particles are formed by agglomerating primary particles with the diameter of D505.8 mu m, the D50 of the secondary particles is 14.6 mu m, and the mass ratio of the single particles to the secondary particles is 1: 1.
(2) 95kg of spherical natural graphite (D5016.0 mu m) and 5kg of petroleum asphalt (D505 mu m) are put into a conical mixer for mixing for 45min, and then the materials are discharged. Then carrying out carbonization treatment at 1300 ℃ in a nitrogen atmosphere, wherein the carbonization process comprises the following steps: keeping the temperature of the mixture at 25-1300 ℃ for 10 hours, keeping the temperature of the mixture at 1300 ℃ for 8 hours, then cooling and discharging. The natural graphite particles (D5016.5 mu m) are prepared without crushing, the discharge capacity is 367.6mAh/g, and the primary efficiency is 93.8%.
(3) And (3) putting 50kg of the artificial graphite particles in the step (1) and 50kg of the natural graphite particles in the step (2) into a conical mixer, mixing for 45min, and discharging. Composite graphite particles (D5016.8 μm), discharge capacity 363.5mAh/g, first efficiency 94.1% were obtained.
Example 3
Taking 220kg (volatile component is 12.7%) of oil-based green coke particles with the particle size D50 of 10 mu m after jaw crushing and mechanical crushing, putting the particles into a roller furnace, adjusting the rotating speed of the roller furnace to be 15Hz, feeding while rotating, adjusting the rotating speed to be 25Hz after feeding, and carrying out a temperature rise program as follows: 25 ℃ to 200 ℃ for 1 hour (the heating rate is 2.92 ℃/min); 200 ℃ to 300 ℃ for 1.5 hours (the heating rate is 1.11 ℃/min); 300 ℃ to 500 ℃ for 2 hours (the heating rate is 1.67 ℃/min); the temperature is kept constant at 500 ℃ for 2 hours. Cooling to normal temperature after cooling by a fan, and discharging. Then carrying out catalytic graphitization treatment at 3100 ℃ under chlorine gas. Artificial graphite particles (D5015.5 μm) were obtained without crushing, and had a discharge capacity of 352.3mAh/g and a first efficiency of 94.5%.
The artificial graphite particles prepared in the step comprise single particles and secondary particles, wherein the single particles are monomer particles with the diameter of D5015.2 mu m, the secondary particles are formed by agglomerating primary particles with the diameter of D506.5 mu m, the D50 of the secondary particles is 13.8 mu m, and the mass ratio of the single particles to the secondary particles is 1.5: 1.
Example 4
The temperature rising procedure is as follows: 25 ℃ to 200 ℃ for 1 hour (the heating rate is 2.92 ℃/min); 200 ℃ to 300 ℃ for 1.5 hours (the heating rate is 1.11 ℃/min); 300 ℃ to 500 ℃ for 4 hours (the heating rate is 0.83 ℃/min); keeping the temperature at 500 ℃ for 4 hours, cooling by a fan and then cooling to 25 ℃.
The rest is the same as example 3.
Example 5
The temperature rising procedure is as follows: 25 ℃ to 500 ℃ for 4 hours (the heating rate is 1.98 ℃/min); keeping the temperature at 500 ℃ for 2 hours, cooling by a fan and then cooling to 25 ℃.
The rest is the same as example 3.
Example 6
The temperature rising procedure is as follows: 25 ℃ to 300 ℃ for 2.5 hours (the heating rate is 1.83 ℃/min); 300 ℃ to 350 ℃ for 1 hour (the heating rate is 0.83 ℃/min); 350 ℃ to 500 ℃ for 2.5 hours (the heating rate is 1 ℃/min); keeping the temperature at 500 ℃ for 4 hours, cooling by a fan and then cooling to 25 ℃.
The rest is the same as example 3.
Example 7
The volatile content of the oil-based green coke particles was 11.5%. The rest is the same as example 3.
Example 8
The D50 particle size of the oil-based green coke particles was 9.4. mu.m. The rest is the same as example 3.
Example 9
The calcined coke particles had a D50 particle size of 9.0. mu.m. The rest is the same as the step (1) in the example 2 to obtain artificial graphite particles.
Example 10
In the step (3), 80kg of the artificial graphite particles in the step (1) and 20kg of the natural graphite particles in the step (2) are taken. The rest is the same as example 1.
Comparative example 1
95kg of spherical natural graphite (D5017.0 mu m) and 5kg of petroleum asphalt (D505 mu m) are put into a conical mixer for mixing for 45min, and then the materials are discharged. Then carrying out carbonization treatment at 1300 ℃ in a nitrogen atmosphere, wherein the carbonization process comprises the following steps: keeping the temperature of the mixture at 25-1300 ℃ for 10 hours, keeping the temperature of the mixture at 1300 ℃ for 8 hours, then cooling and discharging. The prepared natural graphite particles (D5017.3 mu m), the discharge capacity of 369.7mAh/g and the first efficiency of 93.5 percent.
Comparative example 2
The temperature rising procedure is as follows: 25 ℃ to 600 ℃ for 2 hours (the heating rate is 4.79 ℃/min); keeping the temperature of 600 ℃ for 2 hours, cooling by a fan and then cooling to 25 ℃.
The rest is the same as example 3.
Comparative example 3
In the step (3), 20kg of the artificial graphite particles in the step (1) and 80kg of the natural graphite particles in the step (2) are taken. The rest is the same as example 1.
Comparative example 4
The mass percentage of volatile components in the oil-based green coke particles is 17.8%. The rest is the same as example 3.
Comparative example 5
The mass percentage of volatile components in the oil-based green coke particles is 4.5%. The rest is the same as example 3.
Comparative example 6
The oil coke particles have a volatile content of 3.6% by mass and a coking value of 71% by mass. In the mixture of calcined coke particles and asphalt particles, the mass percentage of volatile components is 18.6%. The rest is the same as the step (1) in the example 2 to obtain artificial graphite particles.
Comparative example 7
The mass percentage of volatile components in the oil system calcined coke particles is 0.9 percent, and the coking value of the asphalt particles is 84 percent. In the mixture of calcined coke particles and asphalt particles, 200kg of calcined coke, 5kg of asphalt and 3.4 percent of volatile components by mass. The rest is the same as the step (1) in the example 2 to obtain artificial graphite particles.
Comparative example 8
The volatile content of the oil-based calcined coke particles was 1.8%, and the asphalt particles were replaced with epoxy resin (volatile content was 20%). The rest is the same as the step (1) in the example 2 to obtain artificial graphite particles.
Effect example 1
And (3) performance testing:
the graphite negative electrode materials of examples and comparative examples were subjected to particle size, tap density, specific surface area, and the like, respectively, and the results are shown in table 1. The name and model of the instrument used for the test are as follows: particle size, laser particle size distribution instrument MS 2000; tap density, a compactor FZS 4-4B; specific surface area, specific surface area meter NOVA 2000.
The results of the discharge capacity and the first efficiency tests using the half-cell test method comparative examples and the graphite negative electrode material in comparative examples are shown in table 1.
The half cell test method comprises the following steps: respectively and uniformly mixing the graphite negative electrode materials prepared in the embodiment and the comparative example, N-methyl pyrrolidone containing 6-7% of polyvinylidene fluoride and 2% of conductive carbon black, coating the mixture on a copper foil, and putting the coated pole piece into a vacuum drying oven at the temperature of 110 ℃ for vacuum drying for 4 hours for later use. The simulated cell was assembled in an argon-filled German Braun glove box with an electrolyte of 1MLiPF6+ EC: DEC: DMC 1:1 (volume ratio), with a lithium metal plate as the counter electrode, and the electrochemical performance test was performed on a American ArbinBT2000 model cell tester, with a charge-discharge voltage range of 0.005 to 2.0V and a charge-discharge rate of 0.1C.
The capacity retention rates before and after the cycling of the graphite anode materials in the examples and comparative examples were measured by the full cell test method, and the results are shown in table 1.
The full battery test method comprises the following steps: the graphite of the embodiment and the comparative example of the invention is used as a negative electrode, lithium cobaltate is used as a positive electrode, 1M-LiPF6EC, DMC, EMC (volume ratio) is 1:1 is used as electrolyte to assemble a full cell, and the capacity retention rate of the full cell is tested at 25 ℃ for 500 weeks during 1C charging and discharging.
In addition, the negative electrode sheets of the mixed graphite obtained in the above examples and comparative examples were rolled twice under a pressure of 17.0MPa, and the rolled thickness was measured to calculate the graphite compaction density.
The properties of the above tests are shown in table 1:
TABLE 1 electrochemical and processing Property test results for materials
As can be seen from table 1:
(1) the discharge capacity of the artificial graphite material prepared in the application is more than or equal to 350mAh/g, the first efficiency is more than or equal to 93%, the 1C/1C circulation 500-week capacity efficiency is more than or equal to 89%, the 3C/0.2C capacity retention rate is more than or equal to 75%, and the discharge capacity, the rate capability, the circulation performance and the like are remarkably improved;
(2) after the artificial graphite material and the natural graphite material are compounded, the prepared composite graphite material has the characteristics of high capacity, high compaction and good cycle performance, is suitable for lithium ion secondary batteries with high energy density requirements, has the performance characteristics of excellent artificial graphite cycle performance and high natural graphite capacity, and generates synergistic effect on the performances such as 3C/0.2C capacity retention rate%, 20 ℃ below zero capacity retention rate% and the like.
The above embodiments are preferred embodiments of the present invention, but the present invention is not limited to the above embodiments, and any other changes, modifications, substitutions, combinations, and simplifications which do not depart from the spirit and principle of the present invention should be construed as equivalents thereof, and all such changes, modifications, substitutions, combinations, and simplifications are intended to be included in the scope of the present invention.
Claims (18)
1. The preparation method of the artificial graphite material is characterized by comprising the following steps of:
carrying out temperature programming treatment and graphitization treatment on the raw materials;
the raw materials are petroleum green coke particles or a mixture of calcined coke particles and asphalt particles; in the petroleum green coke or the mixture of the calcined coke particles and the asphalt particles, the mass percentage of volatile components is 5-15%;
the temperature programming treatment comprises the following steps: the end point temperature of the temperature programming treatment is more than or equal to 500 ℃; in the temperature programming treatment, when the temperature is more than or equal to 200 ℃ and less than 500 ℃, the temperature rising rate is less than or equal to 2 ℃/min;
in the temperature programming treatment, when the temperature is more than or equal to 200 ℃ and less than 300 ℃, the temperature rising rate is 1.11-1.98 ℃/min; when the temperature is more than or equal to 300 ℃ and less than 500 ℃, the heating rate is 0.83-1.98 ℃/min.
2. The method for producing artificial graphite material according to claim 1, wherein the petroleum green coke particles have a D50 particle size of 5 to 30 μm;
and/or the mass percentage of volatile components in the petroleum green coke particles is 10-15%;
and/or the D50 particle size of the calcined coke particles is 5-30 μm;
and/or the mass percent of volatile components in the calcined coke particles is 0.1-5%;
and/or the asphalt particles have a D50 particle size of 1-20 μm;
and/or the softening point of the asphalt is more than or equal to 250 ℃, and the coking value is more than or equal to 75%;
and/or in the mixture of calcined coke particles and asphalt particles, the mass percentage of volatile components is 10-15%;
and/or the mass ratio of the calcined coke particles to the asphalt particles is (20-30) to 1;
and/or in the temperature programming treatment, when the temperature is less than 200 ℃, the temperature rising rate is 0.29-5.83 ℃/min;
and/or in the temperature programming treatment, when the temperature is more than or equal to 200 ℃ and less than 500 ℃, the temperature rising rate is 0.17-2.00 ℃/min;
and/or in the temperature programming treatment, when the temperature is more than or equal to 500 ℃, carrying out constant temperature treatment;
and/or the temperature programming treatment is carried out in a roller furnace;
and/or after the temperature programming treatment is finished, cooling by a fan and then carrying out the graphitization treatment;
and/or, the graphitization treatment is carried out according to the following steps: and carrying out catalytic graphitization treatment on the raw material subjected to temperature programming treatment in a chlorine atmosphere at 2800-3200 ℃.
3. The method for producing artificial graphite material according to claim 2, wherein the petroleum green coke particles have a D50 particle size of 5 to 15 μm;
and/or the mass percentage of volatile components in the petroleum green coke particles is 11.50% or 12.7%;
and/or the D50 particle size of the calcined coke particles is 5-15 μm;
and/or the mass percentage of volatile components in the calcined coke particles is 1.8%;
and/or the asphalt particles have a D50 particle size of 1-10 μm;
and/or the coking value of the asphalt is more than or equal to 80 percent;
and/or in the mixture of calcined coke particles and asphalt particles, the mass percentage of volatile components is 11.5%;
and/or the mass ratio of the calcined coke particles to the asphalt particles is 22: 1;
and/or in the programmed heating treatment, when the temperature is lower than 200 ℃, the heating rate is 1.83 ℃/min, 1.98 ℃/min or 2.92 ℃/min;
and/or in the programmed heating treatment, when the temperature is more than or equal to 200 ℃ and less than 500 ℃, the heating rate is 0.83 ℃/min, 1 ℃/min, 1.11 ℃/min, 1.67 ℃/min, 1.83 ℃/min or 1.98 ℃/min;
and/or in the temperature programming treatment, the constant temperature treatment time is 1-10 h;
and/or, when feeding, the rotating speed of the roller furnace is 5-50 Hz;
and/or when the temperature programming treatment is carried out, the rotating speed of the roller furnace is 5-50 Hz;
and/or the temperature of the graphitization treatment is 3000-3200 ℃.
4. The method for preparing an artificial graphite material according to claim 1, wherein the rate of temperature rise is 1.11 ℃/min, 1.83 ℃/min or 1.98 ℃/min when the temperature is not less than 200 ℃ and less than 300 ℃;
and/or when the temperature is more than or equal to 300 ℃ and less than 500 ℃, the heating rate is 0.83 ℃/min, 1 ℃/min, 1.67 ℃/min or 1.98 ℃/min.
5. The method for producing artificial graphite material according to claim 3, wherein the petroleum green coke particles have a D50 particle size of 9.0 μm, 9.4 μm, 10 μm or 11 μm;
and/or the calcined coke particles have a D50 particle size of 9.0 μm, 9.4 μm, 10 μm, or 11 μm;
and/or the asphalt particles have a D50 particle size of 5 μm;
and/or the pitch has a coking value of 84.4%;
and/or in the temperature programming treatment, the constant temperature treatment lasts for 1-4 h;
and/or, when feeding, the rotating speed of the roller furnace is 15 Hz;
and/or when the temperature programming treatment is carried out, the rotating speed of the roller furnace is 25 Hz;
and/or the temperature of the graphitization treatment is 3100 ℃.
6. An artificial graphite material produced by the method for producing an artificial graphite material according to any one of claims 1 to 5.
7. Use of the artificial graphite material according to claim 6 as a battery negative electrode material.
8. The composite graphite material is characterized by comprising the following raw materials: the artificial graphite material and the natural graphite material according to claim 6; the weight ratio of the artificial graphite material to the natural graphite material is more than or equal to 0.43: 1.
9. The composite graphite material of claim 8, wherein the weight ratio of the artificial graphite material to the natural graphite material is (0.43-4): 1.
10. The composite graphite material of claim 8, wherein the weight ratio of the artificial graphite material to the natural graphite material is (1-2.33):1 or 4: 1.
11. The composite graphite material according to any one of claims 8 to 10, wherein the natural graphite material is prepared by a method comprising: the spherical natural graphite particles are coated and carbonized.
12. The composite graphite material according to claim 11, wherein the spherical natural graphite particles have a D50 particle size of 10-50 μ ι η;
and/or, the coating is carried out according to the following steps: mixing and coating the spherical natural graphite particles and a coating agent;
and/or, the carbonization is carried out according to the following steps: in inert atmosphere, increasing the temperature from 25 ℃ to 1300 ℃ for 0.5-24 h; keeping the temperature of 1300 ℃ for 1-10 h.
13. The composite graphite material according to claim 12, wherein the spherical natural graphite particles have a D50 particle size of 15-20 μ ι η;
and/or the coating agent is one or more of petroleum asphalt, coal asphalt and high molecular resin;
and/or the D50 particle size of the coating agent is 1-10 μm;
and/or the mass ratio of the spherical natural graphite particles to the coating agent is (2.5-20): 1;
and/or, the mixing is in a conical blender mixer;
and/or the mixing time is 0.5-1 h.
14. The composite graphite material according to claim 13, wherein the polymer resin is a phenol resin and/or an epoxy resin;
and/or the petroleum asphalt has a softening point of more than or equal to 250 ℃ and a coking value of more than or equal to 75 percent;
and/or the D50 particle size of the coating agent is 5 μm;
and/or the rotating speed of the conical mixer is 10-50 Hz;
and/or the mixing time is 45 min.
15. The composite graphite material of claim 14, wherein the conical blender is operated at a speed of 20 Hz.
16. A method of producing a composite graphite material as claimed in any one of claims 8 to 15, comprising the step of mixing the artificial graphite material and the natural graphite material.
17. Use of the composite graphite material as claimed in any one of claims 8 to 15 as a battery negative electrode material.
18. A lithium ion secondary battery, characterized in that the negative electrode material of the lithium ion secondary battery is the artificial graphite material according to claim 6 or the composite graphite material according to any one of claims 8 to 15.
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| CN112713271B (en) * | 2020-12-29 | 2022-07-05 | 上海杉杉科技有限公司 | Modified graphite material, preparation method thereof, lithium ion battery and application |
| CN113422019B (en) * | 2021-06-24 | 2023-03-21 | 湖南中科星城石墨有限公司 | Graphite negative electrode material, preparation method thereof and secondary battery |
| CN113528171B (en) * | 2021-08-11 | 2022-11-04 | 山东亿维新材料有限责任公司 | Needle coke calcination process |
| CN114653302A (en) * | 2022-03-15 | 2022-06-24 | 上海杉杉新材料有限公司 | Granulation method of artificial graphite, granulated material, artificial graphite, preparation method and application of artificial graphite, and secondary battery |
Citations (10)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102485648A (en) * | 2010-12-03 | 2012-06-06 | 上海杉杉科技有限公司 | Modified graphite, composite graphite material containing the modified graphite and their preparation methods and application |
| CN105794027A (en) * | 2014-07-29 | 2016-07-20 | 株式会社Lg化学 | Graphite secondary particle, and lithium secondary battery comprising same |
| CN105938906A (en) * | 2016-06-18 | 2016-09-14 | 湖南星城石墨科技股份有限公司 | Artificial graphite composite negative electrode material for lithium-ion battery and preparation method of artificial graphite composite negative electrode material |
| CN105958070A (en) * | 2016-06-03 | 2016-09-21 | 田东 | Preparation method for artificial graphite negative electrode material for lithium ion battery |
| CN106486669A (en) * | 2015-11-17 | 2017-03-08 | 上海杉杉科技有限公司 | A kind of high-discharge-rate lithium ion battery graphite cathode material and preparation method thereof |
| CN107507979A (en) * | 2016-06-14 | 2017-12-22 | 上海杉杉科技有限公司 | A kind of preparation method of high jolt ramming artificial plumbago negative pole material |
| CN107579252A (en) * | 2017-09-07 | 2018-01-12 | 福建杉杉科技有限公司 | A kind of high power charcoal bag covers the preparation method of artificial plumbago negative pole material |
| CN108190879A (en) * | 2017-12-25 | 2018-06-22 | 惠州Tcl金能电池有限公司 | Modified artificial graphite and preparation method thereof and lithium ion battery |
| CN108383116A (en) * | 2018-02-11 | 2018-08-10 | 珠海光宇电池有限公司 | Artificial plumbago negative pole material and preparation method thereof and negative electrode of lithium ion battery |
| CN108550850A (en) * | 2018-05-08 | 2018-09-18 | 中航锂电（洛阳）有限公司 | A kind of high power capacity high-pressure solid artificial plumbago negative pole material and preparation method thereof, lithium ion battery |
-
2019
- 2019-05-31 CN CN201910467031.0A patent/CN112018386B/en active Active
Patent Citations (10)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102485648A (en) * | 2010-12-03 | 2012-06-06 | 上海杉杉科技有限公司 | Modified graphite, composite graphite material containing the modified graphite and their preparation methods and application |
| CN105794027A (en) * | 2014-07-29 | 2016-07-20 | 株式会社Lg化学 | Graphite secondary particle, and lithium secondary battery comprising same |
| CN106486669A (en) * | 2015-11-17 | 2017-03-08 | 上海杉杉科技有限公司 | A kind of high-discharge-rate lithium ion battery graphite cathode material and preparation method thereof |
| CN105958070A (en) * | 2016-06-03 | 2016-09-21 | 田东 | Preparation method for artificial graphite negative electrode material for lithium ion battery |
| CN107507979A (en) * | 2016-06-14 | 2017-12-22 | 上海杉杉科技有限公司 | A kind of preparation method of high jolt ramming artificial plumbago negative pole material |
| CN105938906A (en) * | 2016-06-18 | 2016-09-14 | 湖南星城石墨科技股份有限公司 | Artificial graphite composite negative electrode material for lithium-ion battery and preparation method of artificial graphite composite negative electrode material |
| CN107579252A (en) * | 2017-09-07 | 2018-01-12 | 福建杉杉科技有限公司 | A kind of high power charcoal bag covers the preparation method of artificial plumbago negative pole material |
| CN108190879A (en) * | 2017-12-25 | 2018-06-22 | 惠州Tcl金能电池有限公司 | Modified artificial graphite and preparation method thereof and lithium ion battery |
| CN108383116A (en) * | 2018-02-11 | 2018-08-10 | 珠海光宇电池有限公司 | Artificial plumbago negative pole material and preparation method thereof and negative electrode of lithium ion battery |
| CN108550850A (en) * | 2018-05-08 | 2018-09-18 | 中航锂电（洛阳）有限公司 | A kind of high power capacity high-pressure solid artificial plumbago negative pole material and preparation method thereof, lithium ion battery |
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