Processing system and method for manufacturing spheroidized graphite powder using a single variable rpm mill

Abstract

The present disclosure relates to a system (100) for manufacturing spheroidized graphite powder, the system comprising a feeder (104) adapted to deliver primary crushed particles to a grinding section (106). A first classifier (108) is located at the top of the chamber and is configured to receive milled particles and is adapted to separate the milled particles into first particles and second particles. A controller (112) is operably coupled to one or more motors (110), the controller configured to operate the one or more motors at progressively varying RPMs, at higher RPMs which cut the rough edges of the particles to form first fine graphite particles and second shaped graphite particles, and when its RPMs are reduced to lower levels, a surface smoothing process of the shaped particles occurs which produces surface smoothed spherical graphite.

Description

Technical Field

[0001] This disclosure generally relates to graphite spheroidization, and more specifically to a processing system and method using a single variable RPM mill for producing spheroidized graphite powder. Background Technology

[0002] Graphite particles have been widely used as anode materials in lithium-ion secondary batteries and in fuel cell bipolar plates. Natural graphite flakes are typically flat with sharp edges and low tap density, making the fabrication of anodes for lithium-ion batteries difficult. Furthermore, this results in lower electrode density, leading to lower battery energy density and poorer battery life.

[0003] Furthermore, during electrode fabrication, natural graphite flakes are often oriented parallel to the current collector. This orientation slows down the insertion and extraction process of lithium-ion batteries because lithium ions cannot enter the graphite crystal through its "basal surface" facing the electrolyte, but must instead migrate around the flake to the "prismatic surface".

[0004] Therefore, there is a strong need for a process to manufacture spherical graphite from graphite flakes and coke materials. This process can produce spherical graphite particles with high tap density, smooth surface, and higher compactness, resulting in high electrode density, low cost, and high lithium intercalation capacity.

[0005] In conventional processes, according to patents CN101391105A and CN110872118A, manufacturing spherical graphite requires multiple steps, making the process very expensive and time-consuming. This system is configured to feed flake graphite, already ground in a primary pulverizer, to the desired size D50 = 10-30 micrometers, then sequentially to 2 to 5 secondary pulverizers, and then to 10 to 12 forming pulverizers connected in series, collecting the spherical graphite product at the end of the forming pulverizers.

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

[0007] Another embodiment is described in patent US 6,939,526B2, which relates to particles of soft, folded sheets resembling spherical onion layers, and to the fabrication of spherical graphite. However, due to their soft nature, the particles tend to break and flatten when the electrodes are rolled to higher electrode densities, resulting in closed surface porosity and consequently, low-rate charge and discharge performance.

[0008] Another embodiment is described in patent CN112110444A. The system includes three grinding sections within a single chamber with three actuators. Grinded / shaped particles with fine powder exit the grinding chamber and are sorted; larger particles are then guided into the grinding chamber, while the fine powder is collected at the bottom of a cyclone separator. The actuators / motors can be selected to vary the motor's revolutions per minute (RPM). However, the process is carried out at a desired fixed RPM. The system also requires multiple actuators within the grinding chamber.

[0009] Another method disclosed in US2013 / 0130117A1 describes manufacturing spherical graphite in one machine and then feeding the intermediate particles again to another mechanical mill to smooth the particle surface. While it reduces the number of steps, it still requires multiple steps and multiple machines.

[0010] Therefore, it is desirable to overcome the drawbacks, shortcomings and limitations associated with existing solutions and to develop a process for manufacturing spherical graphite that eliminates the multiple steps used in conventional processes for spheroidizing and smoothing graphite materials.

[0011] The purpose of this disclosure

[0012] The purpose of this disclosure generally relates to graphite spheroidization, and more specifically to a processing system and method utilizing a single grinding chamber and a single grinding driver, which continuously / gradually changes the RPM of the mill for the production of spheroidized graphite powder.

[0013] Another object of this disclosure is to provide a system that enables particle forming and surface smoothing in the same grinding chamber by continuously / gradually changing the RPM of the mill drive.

[0014] Another object of the present invention is to provide a system for producing spherical graphite particles that do not break or flatten during the electrode manufacturing process, thereby providing high rate performance of the electrode.

[0015] Another objective of this disclosure is to provide a system that is easy to operate and control.

[0016] Another objective of this disclosure is to provide a cost-effective system by using a small number of motors, mills, and classifiers. Summary of the Invention

[0017] This disclosure generally relates to graphite spheroidization, and more specifically to a processing system and method utilizing a single grinding chamber with continuously / gradually varying RPM of the mill for producing spheroidized graphite powder. The primary objective of this disclosure is to overcome the shortcomings, limitations, and deficiencies of existing systems and solutions by providing a system and method for producing spheroidized graphite powder using a single continuously / gradually variable RPM mill.

[0018] This disclosure relates to a feeder suitable for conveying primary pulverized particles to a closed grinding / shaping section within a chamber. The particles are selected from natural graphite, petroleum and coal tar-based coke powders, and any combination thereof. These modified natural graphite / coke particles are obtained by a manufacturing method comprising the steps of: applying an impact force to the natural graphite / coke particles to cut random edges and spheroidize them at a high RPM, and smoothing the surface of the particles as the RPM continuously / gradually decreases.

[0019] The first classifier is located at the top of the chamber. The first classifier is configured to receive milled / shaped particles and is adapted to separate the powder into first particles 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 another motor is coupled to the first classifier. The grinding and classifier motors can operate independently to rotate gradually / continuously at a variable RPM, from high to low or from low to high. The RPM variation of the grinding motor is described, where x = grinding RPM - y, where y is between 0 and 200 RPM. The RPM variation of classifier-1 is shown, where m = 70% of the classifier's maximum RPM - n, where n is between 0 and 50 RPM.

[0020] A controller is operatively coupled to one or more motors and configured to operate the motors at high RPM to cut the rough edges of the particles to form first and second particles. The controller is also configured to operate a classifier at lower RPM to facilitate the removal of first fine graphite particles through the classifier and further guide the second particles into the grinding chamber, where the surfaces of the formed particles are smoothed at the low RPM of the grinding mill to form spherical graphite, thereby facilitating the smoothing and shaping process within a single grinding system.

[0021] Furthermore, the spheroidizing process is carried out in a single grinding mill by applying impact and shear forces, where the forces are generated by the variable RPM of the rotor through rotating hammers and stationary bushings in the grinding mill, thereby grinding graphite in a short time. Smooth spheroidized graphite with low surface area is obtained by rotating the rotor of one or more motors using a variable RPM from high to low.

[0022] Furthermore, spherical graphite is coated with a carbon source, such as pitch, followed by carbonization / graphitization to produce spherical graphite anode powder, wherein the purified spherical graphite has a particle size of less than 2 μm. 2 With a surface area of ​​ / g and a high tap density of 1.2g / cc, it provides a high first-cycle coulombic efficiency of 368mAh / g and 94%. The spherical graphite produced by the stated process exhibits an orientation index of less than 50. The orientation index was determined by powder X-ray diffraction analysis via I0. 002 / I 110 It is measured by the ratio of peaks. For batteries with high speed and long cycle life, the lower the index, the better.

[0023] The prepared spherical graphite particles have a surface area of ​​less than 8 m² / g at a diameter D50 of 10 μm and less than 6 m² / g at a diameter D50 of 15 μm, exhibiting a smooth surface. The obtained spherical graphite particles have an aspect ratio (L / D) within an optimal range of 1.2, a forming rate exceeding 65%, and a tap density of 0.99 for a diameter D50 of 10 μm.

[0024] Those skilled in the art will understand that this invention avoids a large number of motors, grinding mills, and classifiers, eliminating the need for additional particle usage and assembly operations, thereby reducing system costs. Furthermore, the system can utilize only about ten motors for grinding and spheroidizing, making it easy to operate and control.

[0025] Various objects, features, aspects and advantages of the subject matter of the invention will become more apparent from the following detailed description of preferred embodiments and the accompanying drawings, wherein the same numerals represent the same parts. Attached Figure Description

[0026] The following figures form part of this specification and are included to further illustrate various aspects of this disclosure. A better understanding of this disclosure can be achieved by referring to the accompanying drawings and the detailed description of the specific embodiments shown herein.

[0027] Figure 1A The illustration shows an exemplary single grinding mill grinding and a first classifier according to an embodiment of the present disclosure.

[0028] Figure 1B An exemplary spherical forming process system according to an embodiment of the present disclosure is illustrated.

[0029] Figure 1C An exemplary block diagram of a single processing system according to an embodiment of the present disclosure is illustrated.

[0030] Figure 2A An exemplary block diagram of RPM variation for a grinding motor according to an embodiment of the present disclosure is illustrated.

[0031] Figure 2B An exemplary block diagram is shown for RPM variation of a first classifier motor according to an embodiment of the present disclosure.

[0032] Figures 3A to 3D An exemplary view of spheroidized graphite by scanning electron microscopy (SEM) according to an embodiment of the present disclosure is illustrated.

[0033] Figure 4 An exemplary method for manufacturing spheroidized graphite powder according to an embodiment of the present disclosure is illustrated. Detailed Implementation

[0034] The following is a detailed description of embodiments of this disclosure as depicted in the accompanying drawings. The embodiments are described in such detail to clearly convey this disclosure. If the specification states that a component or feature "may," "can," "is capable of," or "may" be included or have a characteristic, then that particular component or feature need not be included or have a characteristic.

[0035] As used in this description and throughout the claims, “a,” “an,” and “the” have the meaning of plural reference unless the context clearly specifies otherwise. Furthermore, as used in this description, “in” has the meaning of both “in” and “on” unless the context clearly specifies otherwise.

[0036] This disclosure generally relates to graphite spheroidization, and more specifically to a processing system and method using a single system for manufacturing spheroidized graphite powder by continuously / gradually changing the RPM of a mill.

[0037] In this article, the term "spheroidization" refers to the process of shaping graphite flakes into spherical or near-spherical graphite particles.

[0038] The system disclosed herein overcomes the drawbacks, deficiencies, and limitations associated with conventional systems by providing a system comprising a feeder adapted to convey primary pulverized particles into a closed grinding section within a chamber. The particles are selected from natural graphite flakes, petroleum and coal tar-based coke powders, and any combination thereof. The term "flake" describes crystalline graphite composed of highly ordered layers, ultimately defining the particle size ratio.

[0039] Furthermore, a first classifier is located at the top of the grinding chamber. The first classifier is configured to receive the milled particles and is adapted to separate the milled particles into first particles and second particles. A controller is configured to operate one or more motors to continuously / gradually change the RPM to cut the rough edges of the particles to form fine graphite particles, and to gradually decrease the RPM to smooth the surface of the particles to form spherical graphite at the end of the process. The fine graphite particles are passed from the top outlet of the chamber to the first housing, and the spherical graphite, after being formed for a preset time, is passed from the middle outlet of the chamber to the second classifier.

[0040] The controller is configured to perform the spherical forming process by applying impact and shear forces, which are generated using the variable frequency of the rotor via rotating hammers and stationary bushings in the grinding section. The resulting spherical graphite particles have an aspect ratio (L / D) within an optimal range of less than 1.2 and a forming rate exceeding 65%.

[0041] Furthermore, spherical graphite is coated with a carbon source, such as pitch, and then carbonized / graphitized at a temperature ranging from 2600°C to 2900°C to produce graphite anode powder, wherein the purified spherical graphite has a particle size of less than 2 μm. 2 / g surface area and 1.2g / cc tap density for 10-micron powder.

[0042] The treated graphite anode powder provides a discharge capacity exceeding 365 mAh / g and a first-cycle efficiency exceeding 93%. This disclosure is described in detail in the following examples, which may represent more than one embodiment of this disclosure.

[0043] The advantages achieved by the system of this disclosure are clearly apparent from the embodiments provided herein. The system enables the shaping and smoothing of particle surface area. The system avoids particle breakage and flattening during electrode calendering, thereby achieving high-ratio performance. This disclosure provides a small number of motors, mills, and classifiers, resulting in a cost-effective system that is easy to operate and control. The description of terms and features related to this disclosure should be clearly understood from the illustrated and described embodiments; however, the invention is not limited to these embodiments. Various modifications, alterations, variations, substitutions, and equivalents can be made to the embodiments within the scope of this disclosure. Furthermore, the invention may include other embodiments within the scope of the claims but not described in detail below.

[0044] Figure 1A The illustration shows an exemplary single grinding mill grinding and a first classifier according to an embodiment of the present disclosure.

[0045] refer to Figure 1AA single grinding mill processing system 100 (also referred to herein as system 100) is configured to perform spheroidization of graphite. System 100 may include a feeder 104, a grinding section 106 enclosed in a chamber 102, a first classifier 108, a programmable logic controller (PLC) 112, and a motor 110. The particles shown in the embodiments may be natural flake graphite or coke particles.

[0046] In one embodiment, particles are conveyed via feeder 104 to a grinding section 106, where deformed particles are obtained. The particles are primary-ground to approximately 20 micrometers in a primary grinder and fed into the grinding section 106 within chamber 102. The grinding section 106 is coupled to a first classifier 108 located at the top of chamber 102. Chamber 102 may include a top outlet 114 and a middle outlet 116. The top outlet 114 of chamber 102 is coupled to a first housing 118, and the middle outlet 116 is coupled to a second classifier 120. The first housing 118 is coupled to a second housing 122, wherein the second housing 122 may include a bag filter 126, and finally, the second housing 122 is coupled to a blower 128.

[0047] In one embodiment, one or more motors 110 are coupled to grinding section 106 and first classifier 108. The one or more motors 110 are operated to rotate at a gradually variable frequency, from high to low or from low to high RPM. A programmable logic controller (PLC) (also referred to herein as controller 112) is operatively coupled to the one or more motors 110 and valves (124, 130). PLC 112 is configured to operate the one or more motors 110 at a variable RPM. Controller 112 is configured to operate the one or more motors 110 at a high RPM using a gradually changing RPM to cut off the rough edges of the particles, and then gradually reduce to a low RPM to smooth the surface of the graphite. Controller 112 is configured to operate as follows: Figure 2A and Figure 2B As shown, by applying impact and shear forces generated in system 100 through a rotating hammer and a fixed bushing using the variable frequency of the rotor, in Figure 1A and Figure 1B The individual grinding mills shown perform a spheroidizing process, thereby promoting particle grinding in a short time. The hammers are made of hardened steel and carbide tips. The bushings are made of hardened steel and are four times the height of the hammers.

[0048] The first classifier 108 is configured to receive milled particles and is adapted to separate the milled particles (e.g., graphite) into first particles and second particles. The first particles may be fine graphite particles, and the second particles may be spherical graphite. Further, the first classifier 108 may allow only fine graphite particles to be dispensed from the top outlet 114 of the chamber 102, and after forming for a preset time, collect the formed particles, i.e., spherical graphite, at the middle outlet 116 of the chamber 102.

[0049] For example, granules are fed into the chamber for 15 minutes. Initially, while motor 110 maintains a high RPM, the edges of the flakes are cut and begin to bend. The irregular edges of the granules are cut to form fine graphite particles, and motor 110 is gradually reduced to a low RPM frequency, folding the edges to smooth the surface and form spherical graphite particles. The fine particles are allowed to pass through the top outlet 114 of chamber 102. After a preset time, the valve is opened, and the formed particles, such as spherical graphite, pass through the middle outlet 116 and are collected at the bottom of the second classifier 120.

[0050] Fine particles are passed to valve 130 located in the first housing 118 and further processed using bag filter 126 provided in the second housing 122, and then conveyed to blower 128 to obtain fine graphite particles. Spherical graphite is passed to second classifier 120 and collected at the bottom of second classifier 120 via discharge valve 124.

[0051] Figure 1C An exemplary block diagram of a single processing system according to an embodiment of the present disclosure is illustrated. Particles are conveyed via feeder 104 to a grinding section 106. The grinding section 106 is coupled to a first classifier 108, which is configured to receive the ground particles and is adapted to separate the ground particles into first particles and second particles. A controller 112 is operably coupled to one or more motors 110 at high RPM to cut the rough edges of the particles to form first particles belonging to fine graphite particles, and operates at low RPM to smooth the surface of the particles to form second particles belonging to spherical graphite.

[0052] The spherical natural graphite obtained through this process can be coated with a carbon source, such as pitch, and treated at a temperature of approximately 2600°C to 2900°C, simultaneously undergoing carbon coating and purification processes. The spherical graphite is coated with pitch, followed by carbonization / graphitization, resulting in a spherical graphite with a diameter less than 2 μm. 2 Spherical graphite powder with a surface area of ​​ / g and a tap density of 1.15g / cc was first heat-treated at 500°C for about 30 min, and then carbonized at 1,000°C for about one hour. Subsequently, graphitization was carried out at a temperature of about 2900°C.

[0053] In this embodiment, the coating is essentially a partially graphitized carbon shell that protects the spherical graphite particles from exfoliation and improves cycle stability by inhibiting the reaction between the electrolyte and the graphite particles, resulting in increased battery capacity and lifespan. Furthermore, carbon coatings (such as pitch-derived amorphous carbon coatings) effectively reduce irreversible capacity. Carbon pitch coating can also be performed using solvents or other coating techniques.

[0054] Spherical graphite particles are purified to remove harmful elements, including silicon dioxide (SiO2), iron (Fe), and other metallic elements. Purification is performed using various techniques, such as corrosive acidic purification with hydrofluoric acid and thermal purification, or similar techniques. The spherical graphite particles obtained after thermal purification have a particle size of less than 2 μm. 2 With a surface area of ​​ / g and a tap density of 1.2g / cc, it exhibits very high spherical properties of particles.

[0055] Purified natural graphite has a particle size of less than 2 μm. 2 With a surface area of ​​ / g and a high tap density of 1.2g / cc, it yields a first-cycle coulombic efficiency of 368mAh / g and 94%. As analyzed by powder X-ray diffraction, the powder orientation index of the spherical graphite is less than 70.

[0056] Uncoated spherical graphite particles have a surface area of ​​less than 8 m² / g at a diameter D50 of 10 μm and less than 6 m² / g at a diameter D50 of 15 μm, exhibiting a smooth surface. The obtained spherical graphite particles have an aspect ratio (L / D) within an optimal range of 1.2, a forming rate exceeding 65%, and a tap density of 0.99 for a diameter D50 of 10 μm. The low L / D ratio, high tap density, and low surface area indicate good sphericity and a smooth surface.

[0057] refer to Figure 2A and Figure 2B , Figure 2A The RPM variation of the grinding motor is shown, where x = grinding RPM and y is between 0 and 200 RPM. Figure 2B The RPM variation of the first classifier is shown, where m = 70% of the classifier's maximum RPM - n, and n is between 0 and 50 RPM.

[0058] Therefore, this invention overcomes the drawbacks, deficiencies, and limitations associated with existing solutions and provides a cost-effective system that reduces defects, resulting in shaped graphite with a smaller surface area. It also reduces the generation of fine powder, thereby increasing yield. This is achieved by continuously decreasing the RPM from high to low at a predetermined rate. At the higher end of the frequency range, irregular edges of the particles are cut off, and at the lower end of the frequency range, the edges are folded and the surface becomes smooth. Furthermore, the system can be operated and controlled using only about ten motors for grinding and balling, thus reducing capital costs.

[0059] Experimental results

[0060] Figures 3A to 3D An exemplary scanning electron microscope (SEM) view of spheroidized graphite according to an embodiment of the present disclosure is illustrated. Figure 3A and Figure 3B As depicted, considering the diameter D50 of the graphite particles, the correct particle shape was not obtained when the controller operated the motor at 2800 RPM (Comparative Example 1) or 2400 RPM (Comparative Example 2). Therefore, in order to obtain graphite particles with a D50 of 10 micrometers (Example 1), the controller gradually reduced the grinding motor speed from 2800 RPM to 2400 RPM, as shown in the figure. Figure 2A As shown. Where x = 2800 RPM, y = 100 RPM and T1 to T5 = 3 min. The classifier motor follows... Figure 2B The process is controlled, with m = 2600 RPM, n = 50 RPM, and T1 to T5 = 3 min. Gradual control of RPM produces well-formed spherical particles with smooth surfaces, such as... Figure 3C As shown.

[0061] Similarly, to obtain 15-micron D50 graphite spherical particles, the RPM was adjusted as follows; the grinding motor speed was gradually reduced from 1300 RPM to 1900 RPM, as... Figure 2A As shown. Where x = 1300 RPM, y = 100 RPM, and T1 to T5 = 3 min. The classifier motor follows... Figure 2B The process was controlled with m = 2600 RPM, n = 50 RPM, and T1 to T5 = 3 min. This process (Example 2) yielded 15-micron spherical graphite powder with a tap density greater than 1.02 g / cc and a surface area less than 6 m² / g.

[0062] The proposed system 100 can be operated by optimizing process parameters to manufacture particles of different sizes. It can produce 10-micron and 15-micron particles using the same process with different parameters, as shown in Examples 1 and 2. Experimental data for manufacturing spheroidized graphite from a single processing system are presented in Table 1 below.

[0063]

[0064] Table 1: Experimental data for manufacturing spheroidized graphite from a single processing system.

[0065] However, these are just exemplary values; actual values ​​can range widely, and the values ​​included here are for illustrative purposes only. Other values ​​and integer multiples are also possible.

[0066] Figure 4 An exemplary method for manufacturing spheroidized graphite powder according to an embodiment of the present disclosure is illustrated.

[0067] refer to Figure 4 A method 400 for manufacturing spheroidized graphite powder. At block 402, a feeder can convey primary crushed particles to a closed grinding section within a chamber. In block 404, a first classifier can receive the milled particles and is adapted to separate the milled particles into first particles and second particles; the first classifier is located at the top of the chamber.

[0068] At block 406, the controller is operatively coupled to the first classifier and can operate one or more motors at progressively varying RPMs, operating at high RPMs to cut the rough edges of the particles to form first particles and at low RPMs to smooth the surface of the particles to form second particles. One or more motors are coupled to the grinding section and the first classifier, and are adapted to rotate at a variable frequency ranging from high to low or from low to high RPMs.

[0069] It will be apparent to those skilled in the art that some or all of the mentioned features and components can be used to provide the system 100 of this disclosure without departing from the scope of this disclosure. Although various embodiments of this disclosure have been illustrated and described herein, it is apparent that this disclosure is not limited to these embodiments. Various modifications, alterations, variations, substitutions, and equivalents will be apparent to those skilled in the art without departing from the spirit and scope of this disclosure as set forth in the claims.

[0070] Advantages of the present invention

[0071] This invention provides a system capable of forming particles and smoothing their surfaces.

[0072] This invention provides a system to prevent particle breakage and flattening during calendering, thereby maintaining uniform porosity in the electrode, which contributes to high rate performance and long cycling.

[0073] This invention provides a system that is easy to operate and control.

[0074] This invention provides a cost-effective system by using a small number of motors, grinding mills, and classifiers.

Claims

1. A system (100) for manufacturing spheroidized graphite powder, said system comprising: The feeder (104) is adapted to convey the primary crushed particles to the closed grinding section (106) in the chamber (102). A first classifier (108) is located at the top of the chamber and is configured to receive the milled particles and is adapted to separate the milled particles into first particles and second particles. One or more motors (110) connected to the grinding section (106) and the first classifier (108) operate the one or more motors (110) to rotate at a gradually variable frequency of revolutions per minute (RPM) from high to low or from low to high; and A controller (112), operably coupled to the one or more motors, is configured to: Operating the one or more motors at high RPM using gradually varying RPM to cut the rough edges of the particles to form the first particle belonging to the fine graphite particles; and The one or more motors are operated at a low RPM using gradually varying RPM to smooth the surface of the particles, thereby forming a second particle belonging to spherical graphite particles.

2. The system according to claim 1, wherein the particles are selected from natural graphite, artificial graphite, petroleum coke powder, and any combination thereof.

3. The system according to claim 1, wherein the fine graphite particles are transferred from the top outlet (114) of the chamber (102) to the first housing (118), and the spherical graphite particles are transferred from the middle outlet (116) of the chamber (102) to the second classifier (120) after a predetermined forming time.

4. The system of claim 1, wherein the spherical graphite particles are coated with carbon pitch, followed by carbonization to produce spherical graphite powder, wherein the purified spherical graphite particles have a particle size of less than 2 μm. 2 The material has a surface area of ​​ / g and a tap density of 1.2g / cc.

5. The system according to claim 1, wherein the powder orientation index of the spherical graphite particles is less than 40.

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

7. The system of claim 1, wherein the obtained spherical graphite particles have an aspect ratio (L / D) in the optimal range of 1.2, a forming rate of more than 65%, and a tap density of 0.99 g / cc for a diameter D50 of 10 micrometers (μm).

8. The system according to claim 1, wherein the surface area of ​​the spherical graphite particles is less than 8 m² at a diameter D50 of 10 μm. 2 / g, with a diameter D50 of 15μm, the surface area of ​​the spherical graphite particles is less than 6m². 2 / g, with a smooth surface.

9. The system of claim 1, wherein the controller (112) is configured to perform a spheroidizing process by applying impact and shear forces, the forces being generated by a variable frequency of the rotor through rotating hammers and fixed bushings in the grinding section, wherein the spheroidized graphite particles are formed.

10. A method for manufacturing spheroidized graphite powder, the method comprising: The primary crushed particles are conveyed to the closed grinding section in the chamber via a feeder. The chamber receives milled particles at a first classifier, which is adapted to separate the milled particles into first particles and second particles, the first classifier being located at the top of the chamber; and The controller operates one or more motors at high RPM using gradually varying RPM to cut the rough edges of the particles to form the first particles belonging to fine graphite particles, and operates the one or more motors at low RPM using gradually varying RPM to smooth the surface of the particles to form the second particles belonging to spherical graphite, wherein the controller is operatively coupled to the one or more motors, and the one or more motors are coupled to the grinding section and the first classifier.

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