Processing system and method with a single variable RPM mill for the production of spheroidized graphite powder

Abstract

The present disclosure relates to a system (100) for producing spheroidized graphite powder, the system including a feeder (104) adapted to convey primary crushed particles to a grinding section (106). A first classifier (108) is disposed in an upper portion of the chamber and configured to receive the crushed particles and to separate the crushed particles into first particles and second particles. A controller (112) operably coupled to one or more motors (110) is configured to operate the one or more motors at a stepped RPM, at a high RPM, to cut off rough edges of the particles and form first fine graphite particles and second shaped graphite particles. When the RPM decreases to a lower level, a surface smoothing process of the shaped particles occurs, resulting in spheroidized graphite with smooth surfaces.

Description

[Technical Field]

[0001] The present disclosure relates generally to graphite spheroidization, and more particularly to a processing system and method comprising a single variable RPM mill for producing spheroidized graphite powder. [Background technology]

[0002] Graphite particles are widely used as anode materials for lithium-ion secondary batteries and bipolar plates for fuel cells. However, natural graphite flakes are generally flat, have sharp edges, and have low tap density, making them difficult to prepare as anodes for lithium-ion batteries. This results in low electrode density, low battery energy density, and a short life cycle.

[0003] Furthermore, natural graphite flakes tend to orient themselves parallel to the current collector during electrode preparation, which slows the intercalation and deintercalation processes in lithium-ion batteries because lithium ions cannot enter the graphite crystals from the "basal plane" facing the electrolyte but must migrate around the flake to the "edge plane."

[0004] Therefore, there is a strong demand for a process to produce spherical graphite from graphite flake and coke materials, which would result in compact spherical graphite particles with high tap density and smooth surfaces, resulting in electrodes with high density, low cost, and high lithium insertion capacity.

[0005] In conventional processes such as those described in patent documents CN101391105A and CN110872118A, the production of spherical graphite requires multiple steps, making the process very expensive and time-consuming.This system is configured so that flake graphite, which has been ground to the required size of D50 = 10 to 30 microns in a primary crusher, is sequentially fed to secondary crushers No. 2 to No. 5, and then sequentially fed to molding crushers No. 10 to No. 12, and the spherical graphite product is recovered at the end of the molding crusher.

[0006] Therefore, conventional processes require multiple systems, approximately 20 in total, to produce spherical graphite. Each system consists of a feeder, mill, primary classifier, secondary classifier, bag filler, blower, and control system. This multi-system approach makes controlling and operating these processes extremely difficult.

[0007] Another example is described in patent US6,939,526 B2, which describes soft flake particles that are folded like spherical onion layers into spherical graphite. However, due to their soft nature, the particles tend to break and flatten during calendering of the electrode to increase electrode density, resulting in closed surface porosity and poor charge / discharge performance.

[0008] Yet another example is described in Patent CN112110444A. The system has three grinding sections in a single chamber with three drives. The ground / formed particles, including fines, exit the grinding chamber and are classified, then the larger particles are directed back into the grinding chamber and the fines are collected at the bottom of a cyclone. The drive / motor has the option to vary the motor's revolutions per minute (RPM). However, the process is run at a fixed RPM as required. This system required multiple drives in the grinding chamber.

[0009] Yet another method disclosed in US2013 / 0130117A1 describes producing spherical graphite in one machine and then feeding the intermediate particles to another mechanical grinding machine to smooth the particle surface. This method reduces the number of steps, but still requires multiple steps and multiple machines.

[0010] Therefore, it is desirable to develop a process for producing spheroidal graphite that overcomes the drawbacks, shortcomings, and limitations associated with existing solutions and eliminates the multiple steps used in conventional processes for spheroidizing and smoothing graphite material. Purpose of this disclosure

[0011] The object of this disclosure relates generally to graphite spheroidization, and more particularly to a processing system and method for producing spheroidized graphite powder having a single grinding chamber with a single grinding drive for continuous / stepwise variation of mill RPM.

[0012] Another object of the present disclosure is to provide a system that can perform particle shaping process and surface smoothing in the same grinding chamber by continuously / stepwise changing the RPM of the mill drive.

[0013] Another object of the present disclosure is to provide a system that can provide spherical graphite particles that do not break or flatten during the electrode manufacturing process and have high-speed performance for the electrode.

[0014] Another object of the present disclosure is to provide a system that is easy to operate and control.

[0015] It is yet another object of the present disclosure to provide a low number of motors, mills, and classifiers to provide a cost-effective system. Summary of the Invention

[0016] The present disclosure relates generally to graphite spheroidization, and more particularly to a processing system and method having a single grinding chamber with continuously / stepwise variable mill RPM for producing spheroidized graphite powder.The primary objective of the present disclosure is to overcome the drawbacks, limitations, and shortcomings of existing systems and solutions by providing a system and method with a single continuously / stepwise variable mill RPM for producing spheroidized graphite powder.

[0017] The present disclosure relates to a feeder adapted to convey primary crushed particles to a grinding / shaping section enclosed in a chamber. The particles are selected from natural graphite, petroleum- and coal-tar-based coke breeze, and any combination thereof. These modified natural graphite / coke particles are obtained by a manufacturing method that includes applying impact forces to the natural graphite / coke particles at high RPM to effect random edge shearing and spheroidization, followed by successive / stepwise reductions in the RPM to allow for smoothing of the particle surface.

[0018] The first classifier is positioned at the top of the chamber. The first classifier is configured to receive the crushed / molded particles and is adapted to separate the powder into first and second particles. The first particles are fine graphite particles, and the second particles are spherical graphite particles. One motor is coupled to the grinding section, and the other motor is coupled to the first classifier. The grinding motor and the classifier motor can be independently operated to rotate at RPMs that are stepwise / continuously variable, from high to low or from low to high. The RPM variation of the grinding motor is shown, where x = RPM of the grinding process y, where y is between 0 and 200 RPM. The RPM variation of classifier-1 is shown, where m = 70% of the maximum RPM of classifier-n, where n is between 0 and 50 RPM.

[0019] a controller operably coupled to the one or more motors, the controller configured to operate the one or more motors at a high RPM to cut off the rough edges of the grains at the high RPM to form the first and second particles, the controller configured to operate the classifier at a low RPM to remove the first fine graphite particles through the first classifier and direct the second particles further to a grinding chamber, and the surfaces of the shaped particles are smoothed in a grinding mill at a low RPM to form spheroidal graphite, thereby facilitating the smoothing and shaping process in a single grinding system.

[0020] Furthermore, the spherical forming process is carried out in a single mill by applying impact and shear forces, which are generated by rotating hammers and stationary liners in the mill at variable rotor RPMs, thereby quickly grinding the graphite. Smooth spherical graphite with low surface area is obtained by rotating the rotors of one or more motors at variable RPMs, from high to low.

[0021] In addition, spherical graphite is coated with a carbon source such as pitch and then carbonized / graphitized to obtain spherical graphite anode powder, and the purified spherical graphite has a surface area of ​​2m 2 / g and a high tap density of 1.2 g / cc, which results in 368 mAh / g and a high first cycle columbic efficiency of 94%. The nodular graphite produced by the declared process exhibits an orientation index of less than 50. The orientation index is determined by powder X-ray diffraction analysis. 002 / I 110 It is measured by the ratio of peak to peak. A lower index is better for cells with high rate and long cycle life.

[0022] The surface area of ​​the obtained spherical graphite particles is 8 m when the diameter D50 is 10 μm. 2 / g, and the diameter D50 is 15 μm. 2 The obtained spherical graphite particles have a length-to-diameter (L / D) ratio in the optimum range of 1.2, a molding yield of over 65%, and a tap density of 0.99 when the diameter D50 is 10 μm.

[0023] Those skilled in the art will appreciate that the present invention avoids the need for multiple motors, mills, and classifiers, eliminates the need for additional particle usage and additional assembly operations, thereby reducing the cost of the system. Moreover, the system requires only about 10 motors for milling and spheronization, and is easy to operate and control.

[0024] Various objects, features, aspects and advantages of the present subject matter will become more apparent from the following detailed description of preferred embodiments, taken in conjunction with the accompanying drawings in which like numerals represent like elements.

[0025] The following drawings form part of the present specification and are included to further explain aspects of the present disclosure. The present disclosure may be better understood by reference to the drawings in combination with the detailed description of specific embodiments presented herein. [Brief explanation of the drawings]

[0026] [Figure 1A] 1 illustrates an exemplary single mill grinding and first classifier according to one embodiment of the present disclosure. [Figure 1B] 1 illustrates an exemplary spherical molding process system according to one embodiment of the present disclosure. [Figure 1C] FIG. 1 illustrates an exemplary block diagram of a single processing system, according to one embodiment of the present disclosure. [Figure 2A] 1 illustrates an exemplary block diagram of RPM variation of a grinding motor according to one embodiment of the present disclosure. [Figure 2B] FIG. 10 illustrates an example block diagram of RPM variation of the first classifier motor according to one embodiment of the present disclosure. [Figure 3] 3A-3D show exemplary views of scanning electron microscope (SEM) of spheroidized graphite, according to one embodiment of the present disclosure. [Figure 4] 1 illustrates an exemplary method for producing spheroidized graphite powder according to one embodiment of the present disclosure. DETAILED DESCRIPTION OF THE INVENTION

[0027]

[0013] Below is a detailed description of embodiments of the present disclosure as illustrated in the accompanying drawings. The embodiments are in sufficient detail to clearly convey the present disclosure. When the specification states that a certain component or feature "may," "can," "could," or "might" be included or have a characteristic, that particular component or feature does not have to be included or have that characteristic.

[0028] As used in this description and in the claims that follow, the meanings of "a," "an," and "the" include plural references unless the context clearly dictates otherwise. Also, as used in this description, the meaning of "in" includes "in" and "on" unless the context clearly dictates otherwise.

[0029] The present disclosure relates generally to graphite spheroidization, and more particularly to a processing system and method having a single system with continuous / stepwise variation of mill RPM to produce spheroidized graphite powder.

[0030] As used herein, the term "spheroidization" refers to the forming of graphite flake particles into spherical or nearly spherical graphite particles.

[0031] The proposed system disclosed in this disclosure overcomes the drawbacks, shortcomings, and limitations associated with conventional systems by providing a system including a feeder adapted to transport primary crushed particles to a grinding section enclosed in a chamber. The particles are selected from natural graphite flakes, petroleum- and coal-tar-based coke breeze, and any combination thereof. The term "flake" refers to crystalline graphite composed of highly ordered layers, ultimately defining the size ratio of the particles.

[0032] Further, a first classifier is disposed at the top of the grinding chamber, the first classifier configured to receive the ground particles and adapted to separate the ground particles into first particles and second particles. The controller is configured to operate one or more motors to continuously / stepwise change the RPM to cut off the rough edges of the particles to form fine graphite particles and gradually decrease the RPM at a low rate to smooth the particle surfaces to form spheroidal graphite particles produced at the end of the process. The fine graphite particles pass through an upper exit of the chamber into the first enclosure, and the spheroidal graphite particles pass through a central exit of the chamber into the second classifier after being formed for a preset time.

[0033] The controller is configured to execute the spherical forming process by applying impact and shear forces, which are generated by the rotating hammer and fixed liner of the grinding section at variable rotor frequencies. The obtained spherical graphite particles have an optimal length-to-diameter (L / D) ratio of less than 1.2, and the forming yield is greater than 65%.

[0034] Additionally, graphite anode powder is produced by coating spherical graphite with a carbon source such as pitch and then carbonizing / graphitizing it at temperatures ranging from 2600°C to 2900°C, where the refined spherical graphite has a surface area of ​​2m for a 10-micron powder. 2 / g and has a tap density of 1.2 g / cc.

[0035] The treated graphite anode powder exhibited a discharge capacity of over 365 mAh / g and a first cycle efficiency of over 93%. The present disclosure can be described in more detail in the following examples, which may represent multiple embodiments of the present disclosure.

[0036] The advantages achieved by the system of the present disclosure may be apparent from the embodiments provided herein. The system enables a particle surface area shaping and smoothing process. The system avoids particle breakage and flattening during electrode calendering, resulting in high-speed performance. The present disclosure provides several motors, mills, and classifiers, resulting in a cost-effective system that is easy to operate and control. While the explanations of terms and features associated with the present disclosure are apparent from the illustrated and described embodiments, the present invention is not limited to these embodiments alone. Numerous modifications, changes, variations, substitutions, and equivalents of the embodiments are possible within the scope of the present disclosure. Furthermore, the present invention may include other embodiments within the scope of the claims that are not described in detail with respect to the following description.

[0037] FIG. 1A illustrates an exemplary single mill grinding and first classifier according to one embodiment of the present disclosure.

[0038] 1A, a single grinding processing system 100 (also referred to herein as system 100) is configured to perform spheroidization of graphite. System 100 can include a feeder 104 enclosed in a chamber 102, a grinding section 106, a first classifier 108, a programmable logic controller (PLC) 112, and a motor 110. The particles shown in the example can be natural flake graphite or coke particles.

[0039] In one embodiment, particles are transported via a feeder 104 to a grinding section 106, where the particles are deformed. The particles are crushed to approximately 20 micrometers in a primary crusher and then fed to the grinding section 106 within the chamber 102. The grinding section 106 is coupled to a first classifier 108 located at the top of the chamber 102. The chamber 102 may include an upper outlet 114 and a middle outlet 116. The upper outlet 114 of the chamber 102 is coupled to a first enclosure 118, and the middle outlet 116 is coupled to a second classifier 120. The first enclosure 118 is coupled to a second enclosure 122, which may include a bag filter 126, and finally, the second enclosure 122 is coupled to a blower 128.

[0040] In one embodiment, one or more motors 110 are coupled to the grinding section 106 and the first classifier 108. The one or more motors 110 are operated to rotate at a frequency that is variable in steps from a high RPM to a low RPM or from a low RPM to a high RPM. A programmable logic controller (PLC) (also referred to herein as controller 112) is operably coupled to the one or more motors 110 and the valves (124, 130). The PLC 112 is configured to operate the one or more motors 110 at variable RPMs. The controller 112 is configured to operate the one or more motors in a stepwise manner at a high RPM to cut through rough edges and then gradually reduce the RPM to a low RPM to enable a smooth surface of the graphite. The controller 112 is configured to perform the spherical forming process in the single mill shown in FIGS. 1A and 1B, respectively, by applying impact and shear forces generated by the rotating hammers and stationary liners in the system 100 at variable rotor frequencies to facilitate rapid particle grinding, as shown in FIGS. 2A and 2B, respectively. The hammers are made of hardened steel and carbide-tipped hammers. The liners are made of hardened steel and are four times the height of the hammers.

[0041] The first classifier 108 is configured to receive the pulverized particles and is adapted to separate the pulverized particles, e.g., graphite, into first particles and second particles. The first particles can be fine graphite particles, and the second particles can be spherical graphite. Furthermore, the first classifier 108 can discharge only the fine graphite particles from an upper outlet 114 of the chamber 102, while the formed particles, i.e., spherical graphite, are collected at a central outlet 116 of the chamber 102 after forming for a predetermined period of time.

[0042] For example, particles are fed into the chamber for 15 minutes. Initially, the motor 110 is maintained at a high RPM, causing the flake edges to break and begin to bend. The irregular edges of the particles are broken off to form fine graphite particles. The motor 110 frequency is then gradually reduced to a lower RPM, causing the edges to fold and smooth the surface, forming spherical graphite particles. The fine particles are allowed to pass through the top outlet 114 of the chamber 102. After a preset time, a valve is opened, allowing the formed particles, e.g., spherical graphite, to pass through the central outlet 116 and collect at the bottom of the second classifier 120.

[0043] The fine particles are passed to a valve 130 in the first enclosure 118, further processed in a bag filter 126 in the second enclosure 122, and conveyed to a blower 128 to obtain fine graphite particles. The spherical graphite is passed to the second classifier 120 and collected at the bottom of the second classifier 120 through a discharge valve 124.

[0044] 1C shows an exemplary block diagram of a single processing system according to one embodiment of the present disclosure. Particles are conveyed through a feeder 104 to a grinding section 106. The grinding section 106 is coupled to a first classifier 108, which is configured to receive the pulverized particles and adapted to separate the pulverized particles into first particles and second particles. A controller 112 is operably coupled to one or more motors 110 operating at a high RPM to cut rough edges of the particles to form first particles representing fine graphite particles and at a low RPM to smooth the surfaces of the particles to form second particles representing spheroidal graphite.

[0045] The spherical natural graphite obtained by this process can be coated with a carbon source such as pitch and treated at temperatures of approximately 2600°C to 2900°C to carry out the carbon coating and purification process together. After the spherical graphite is coated with pitch, it is carbonized / graphitized, resulting in a surface area of ​​2m. 2 The resulting graphite powder is spherical and has a tap density of 1.15 g / cc and a viscosity of less than 1000 kJ / g. First, the pitch-coated graphite is heat-treated at 500°C for about 30 minutes, then carbonized at 1,000°C for about 1 hour. Graphitization then continues at a temperature of about 2,900°C.

[0046] In embodiments, the coating is essentially a partially graphitized carbon shell that protects the spherical graphite particles from exfoliation and inhibits the reaction between the electrolyte and the graphite particles, thereby improving cycling stability and resulting in increased battery capacity and lifespan. Furthermore, carbon coatings, such as pitch-derived amorphous carbon coatings, effectively reduce irreversible capacity. Carbon pitch coatings can also be applied using solvents or other coating techniques.

[0047] The purification of spherical graphite particles is carried out to remove harmful elements, including silicon dioxide (SiO2), iron (Fe), and other metallic elements. The purification is carried out by several purification techniques, such as strong acid purification using hydrofluoric acid, thermal purification, or other similar techniques. The spherical graphite particles obtained after thermal purification have a surface area of ​​2 m 2 / g and a tap density of 1.2 g / cc, indicating that the particles are highly spherical.

[0048] Refined natural graphite has a surface area of ​​2m 2 / g and a high tap density of 1.2 g / cc, which results in a yield of 368 mAh / g and a first cycle columbic efficiency of 94%. Powder X-ray diffraction analysis shows that the powder orientation index of the spherical graphite is less than 70.

[0049] The surface area of ​​an uncoated spherical graphite particle is 8 m when the diameter D50 is 10 μm. 2 / g, and the diameter D50 is 15 μm. 2 / g and has a smooth surface. The obtained spherical graphite particles have a length-to-diameter (L / D) ratio in the optimum range of 1.2, a molding yield of over 65%, and a tap density of 0.99 when the diameter D50 is 10 μm. The low L / D ratio, high tap density, and small surface area indicate a smooth surface and good sphericity.

[0050] 2A and 2B, Fig. 2A shows the change in RPM of the grinding motor, where x = RPM of the grinding process and y is 0-200 RPM. Fig. 2B shows the change in RPM of the first classifier, where m = 70% RPM of the maximum RPM of the classifier-n and n is 0-50 RPM.

[0051] Thus, the present invention overcomes the drawbacks, shortcomings, and limitations associated with existing solutions and provides a cost-effective system for producing compacted graphite with reduced surface area and reduced defects. Fines generation is also reduced, improving yield. This is achieved by continuously varying the RPM from high to low at a predetermined decreasing rate. At the high end of the frequency, irregular edges of the particles are cut, while at the low end of the frequency, the edges are folded and the surface is smoothed. Furthermore, the system requires only about 10 motors for milling and spheronization, making it easier to operate and control, thereby reducing capital costs. Experimental results

[0052] 3A-3D show exemplary scanning electron microscope (SEM) images of spheroidized graphite according to one embodiment of the present disclosure. Considering the diameter size D50 of the graphite particles as shown in FIGS. 3A and 3B, if the controller operates the motor at 2800 RPM (Com. Ex-1) or 2400 RPM (Com. Ex-2), the appropriate shape of the particles will not be obtained. Therefore, to obtain graphite particles (Ex-1) with a D50 of 10 microns, the controller operates the grinding motor to gradually decrease from 2800 RPM to 2400 RPM, as shown in FIG. 2A, where x = 2800 RPM, y = 100 RPM, and T1-T5 = 3 minutes. The classifier motor is controlled as shown in FIG. 2B, with m = 2600 RPM, n = 50 RPM, and T1-T5 = 3 minutes. By controlling the RPM stepwise, good spherical particles with smooth surfaces can be obtained, as shown in Figure 3C.

[0053] Similarly, to obtain graphite spherical particles with a D50 of 15 microns, the RPM is adjusted as follows: the grinding motor is gradually decreased from 1300 RPM to 1900 RPM, as shown in Figure 2A, where x = 1300 RPM, y = 100 RPM, and T1 to T5 = 3 minutes. The classifier motor is controlled as shown in Figure 2B, where m = 2600 RPM, n = 50 RPM, and T1 to T5 = 3 minutes. This process, Example 2, produced graphite spherical particles with a tap density of over 1.02 g / cc and a surface area of ​​6 m. 2 15 micron spherical graphite powder of less than 15 microns / g is obtained.

[0054] The proposed system 100 can be operated to produce different particle sizes by optimizing the process parameters. As shown in Examples 1 and 2, 10 micron and 15 micron particles can be obtained by using different parameters in the same process. Experimental data for producing spheroidized graphite from a single processing system are shown in Table 1 below. [Table 1]

[0055] However, these are merely exemplary values, and the actual values ​​may vary widely; the values ​​included here are merely exemplary, and other values ​​and integer multiples are also possible.

[0056] FIG. 4 illustrates an exemplary method for producing spheroidized graphite powder according to one embodiment of the present disclosure.

[0057] 4, a method 400 for producing spheroidized graphite powder is shown. In block 402, a feeder can transport primary crushed particles to a grinding section enclosed in a chamber. In block 404, a first classifier can receive the crushed particles and is adapted to separate the crushed particles into first particles and second particles, the first classifier being disposed at an upper portion of the chamber.

[0058] In block 406, the controller is operably coupled to the first classifier and operates one or more motors at stepped RPMs, at a high RPM to cut off rough edges of the particles to form first particles and at a low RPM to smooth surfaces of the particles to form second particles. One or more motors are coupled to the grinding section and the first classifier, and the one or more motors are adapted to rotate at a variable frequency from high RPM to low RPM or from low RPM to high RPM.

[0059] It will be apparent to those skilled in the art that the system 100 of the present disclosure may be provided using some or all of the features and components described without departing from the scope of the present disclosure. While various embodiments of the present disclosure have been illustrated and described herein, it will be apparent that the present disclosure is not limited to these embodiments. Numerous modifications, changes, variations, substitutions, and equivalents will be apparent to those skilled in the art without departing from the spirit and scope of the present disclosure, as defined in the claims. Advantages of the Invention

[0060] The present invention provides a system that enables particle shaping and surface smoothing processes.

[0061] The present invention provides a system that avoids particle breakage and flattening during calendering, thereby maintaining uniform porosity within the electrode, which aids in high rate performance and long cycles.

[0062] The present invention provides a system that is easy to operate and control.

[0063] The present invention provides a low number of motors, mills, and classifiers resulting in a cost-effective system.

Claims

1. A system (100) for producing spheroidized graphite powder, comprising: a feeder (104) adapted to convey the primary crushed particles to a grinding section (106) enclosed in the chamber (102); a first classifier (108) disposed in an upper portion of the chamber, the first classifier (108) configured to receive the pulverized particles and adapted to separate the pulverized particles into first particles and second particles; one or more motors (110) coupled to the grinding section (106) and the first classifier (108), the one or more motors (110) being operable to rotate at a number of revolutions (RPM) that can be varied in steps from a high to a low or from a low to a high number; a controller (112) operably coupled to the one or more motors, the controller comprising: operating the one or more motors at a high RPM in stepped RPMs to cut the coarse edges of the grains and form the first particles associated with fine graphite particles; operating the one or more motors at a low RPM with stepwise varying RPM to smooth the surfaces of the particles and form the second particles relative to the spherical graphite particles; The controller and A system comprising:

2. 10. The system of claim 1, wherein the particles are selected from natural graphite, synthetic graphite, petroleum coke powder, and any combination thereof.

3. 2. The system of claim 1, wherein the fine graphite particles pass from an upper outlet (114) of the chamber (102) to a first enclosure (118), and the spherical graphite particles, after being shaped for a predetermined time, pass from a central outlet (116) of the chamber (102) to a second classifier (120).

4. The spherical graphite particles are coated with carbon pitch and then carbonized to form the spherical graphite powder, and the refined spherical graphite particles are 2 m ２ 10. The system of claim 1, wherein the material has a surface area of ​​less than 1.0 g / cc and a tap density of 1.2 g / cc.

5. 10. The system of claim 1, wherein the spherical graphite particles have a powder orientation index of less than 40.

6. The system of claim 1 , wherein the low surface area, smooth, spherical graphite particles are obtained by rotating rotors of one or more motors (110) at varying RPMs.

7. 2. The system of claim 1, wherein the obtained spherical graphite particles have a length to diameter (L / D) ratio in an optimum range of 1.2, a molding yield of more than 65%, and a tap density of 0.99 g / cc when the diameter D50 is 10 microns (μm).

8. The surface area of ​​the spherical graphite particles is 8 m when the diameter D50 is 10 μm. ２ / g, and the diameter D50 is 15 μm. ２ 10. The system of claim 1, wherein the surface is smooth and the surface has a viscosity of less than 1000 MPa.

9. 2. The system of claim 1, wherein the controller (112) is configured to perform a spherical forming process by applying impact and shear forces, the forces being generated by rotating hammers and stationary liners of the grinding section at variable speeds of the rotor to form the spherical graphite particles.

10. A method (400) for producing spheroidized graphite powder, comprising: Conveying the primary crushed particles by a feeder to a grinding section surrounded by a chamber (402); receiving (404) the pulverized particles in a first classifier, the first classifier being adapted to separate the pulverized particles into first particles and second particles, the first classifier being positioned at an upper portion of the chamber; and operating, by a controller, one or more motors at a high RPM in a stepped manner to cut off rough edges of the particles to form the first particles, which correspond to fine graphite particles, and operating the one or more motors at a low RPM in a stepped manner to smooth surfaces of the particles to form the second particles, which correspond to spheroidal graphite (406), wherein the controller is operably coupled to the one or more motors coupled to the grinding section and the first classifier (406). A method comprising:

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