Jet mill capable of removing static electricity and method for pulverizing sulfide-based solid electrolyte using same

Abstract

The jet mill capable of removing static electricity according to the present invention is characterized in that: when a raw material is fed into a hollow grinding main body through a predetermined feeding pipe from a feeding part, and the raw material fed into the grinding main body is filled to a certain height or more, the static electricity is removed; the raw materials collide with each other and are pulverized by strong jet air jetted from an air nozzle provided in the grinding body, and the jet mill removes static electricity inside the grinding body by grounding an upper portion and a lower portion of the grinding body.

Description

Technical Field

[0001] The present invention relates to a jet mill capable of removing static electricity and a method for crushing a sulfide solid electrolyte using the same. Specifically, the present invention relates to a jet mill capable of removing static electricity and a method for crushing a sulfide solid electrolyte using the same. The jet mill can remove static electricity inside a grinding body for crushing, thereby making it easy to adjust the particle size and improving the crushing efficiency. Background Art

[0002] In recent years, secondary batteries have been widely used in electronic devices such as smartphones.

[0003] Secondary batteries use lithium as the positive electrode, and are charged by the movement of lithium ions from the positive electrode to the negative electrode, and discharged and generate electricity by the movement of lithium ions from the negative electrode to the positive electrode.

[0004] Such lithium secondary batteries have the advantages of high energy density and long life, and are therefore widely used in a variety of electronic devices. In recent years, the demand has been increasing due to the rapid growth of the electric vehicle market.

[0005] However, such lithium secondary batteries use an organic solvent as an electrolyte for ion transfer, and therefore accidents may occur due to leakage or volatilization of the electrolyte, which poses a problem in terms of safety.

[0006] Solid electrolytes developed in recent years are a technology that uses solid-phase sulfide compounds to replace existing liquid-phase electrolytes. Since only lithium ions move inside the electrolyte, there are no side reactions and it has the advantages of very excellent safety and durability.

[0007] Among the solid electrolytes used in lithium secondary batteries, the compound represented by Li7-XPS6-xClx has a cubic argyrodite-type crystal structure. Due to its high ionic conductivity and electrochemical stability over a wide temperature range, it has attracted much attention as a mass-produced sulfide solid electrolyte.

[0008] This solid electrolyte is prepared into particles of a certain size through a grinding process after synthesis.

[0009] The existing solid electrolyte grinding process usually uses a ball mill. However, for this ball mill, in order to prepare particles less than 10 μm required in the solid electrolyte particles, not only does it take tens of hours of process time, but there are also problems such as the formation of carbon compounds based on solvent reactions and the resulting decrease in conductivity.

[0010] Therefore, in recent years, in order to adjust the particle size of solid electrolytes, a method of dry-grinding particles using a jet mill has been mainly used.

[0011] Figure 1 is a diagram schematically showing an existing jet mill, Figure 2 This is a diagram for explaining the process of raw material pulverization in a conventional jet mill.

[0012] like Figure 1 As shown, the conventional jet mill includes: a feeding portion 10 , a grinding body 20 , a cyclone separator (Cyclone) 30 , a bag filter 40 and a blower 50 .

[0013] The jet mill constructed in this way passes Figure 2 The process shown is used to crush the raw materials.

[0014] Right now, The raw material is fed from the feed section 10 through a predetermined feed pipe 12 into the hollow grinding body 20. When the raw materials put into the grinding body 20 are filled to a certain height, the strong jet air ejected from the air nozzle 24a provided at the lower part of the grinding body 20 causes the raw materials to collide with each other and be crushed. The crushed raw material particles rise with the air flow. When the particle size is below a certain size, they pass through the classifying wheel 26a. When the particle size is above a certain size, they fall again along the inner wall of the grinding body 20 to the lower part of the grinding body 20. The particles passing through a classifying wheel 26a move to a product collecting portion.

[0015] Here, unexplained reference numeral 28 is a first product moving pipe (connecting the classifying wheel 26a and the cyclone separator 30), and unexplained reference numeral 32 is a second product moving pipe (connecting the cyclone separator 30 and the bag filter 40).

[0016] As described above, the conventional jet mill can inject high-pressure air through the air nozzle 24a to cause mutual collision between the crushed particles, thereby obtaining particles of a desired size.

[0017] The jet mill is mainly used to pulverize sulfide-based solid electrolyte (LPSCl), and is useful in controlling a desired particle size by using only air.

[0018] However, the conventional jet milling as described above may generate static electricity inside the grinding body 20 . Due to the ductile properties of the solid electrolyte, particles may aggregate and adhere to the inner wall surface of the grinding body 20 .

[0019] Therefore, there are problems that it is difficult to adjust the particle size when pulverizing the solid electrolyte, and the pulverization efficiency decreases. Summary of the invention Technical Problems to be Solved by the Invention

[0020] The present invention is proposed to solve the above-mentioned various existing problems. The purpose of the present invention is to provide a jet mill capable of removing static electricity and a method for crushing sulfide solid electrolytes using the same, which can remove static electricity inside the grinding body for crushing, thereby making it easy to adjust the particle size and improve the crushing efficiency. Technical Solution

[0021] In order to achieve the above-mentioned purpose, according to the first aspect of the present invention, a jet mill capable of removing static electricity is characterized in that when raw materials are fed from a feeding portion through a prescribed feeding pipe into a hollow grinding body, and the raw materials fed into the grinding body are filled to a certain height or above, strong jet air is ejected from an air nozzle arranged in the grinding body to cause the raw materials to collide and be crushed, and the jet mill removes static electricity inside the grinding body by grounding the upper and lower parts of the grinding body.

[0022] A horizontally disposed concave lower plate may be disposed at the lower side of the interior of the grinding body, a plurality of air nozzles may be spaced apart along the edge of the lower plate, and the air nozzles may be disposed toward the center of the lower plate.

[0023] The lower plate may be made of ceramic.

[0024] A cover may be provided at the open upper end of the grinding body, and a grading wheel may be provided inside the cover.

[0025] A horizontally arranged upper plate may be provided on the upper side of the grinding body, and one or more feed holes may be formed on the upper plate in a vertically penetrating manner along the circumferential direction, and the raw material supplied from the feed pipe may be put into the feed holes.

[0026] The upper plate may be made of ceramic.

[0027] The feed pipe may be provided with a predetermined ionizer to supply ionized air while supplying the raw material to the feed hole of the upper plate, so that the raw material is not accumulated on the upper plate.

[0028] On the other hand, according to the second aspect of the present invention, a method for crushing a sulfide solid electrolyte using an air flow mill capable of removing static electricity is characterized in that an air flow mill is used, in which, when a sulfide solid electrolyte is fed from a feed portion through a prescribed feed pipe into a hollow grinding body and the sulfide solid electrolyte fed into the grinding body is filled to a height above a certain level, strong jet air is ejected from an air nozzle disposed at a lower portion of the grinding body to cause the sulfide solid electrolytes to collide and crush each other, and the air flow mill removes static electricity inside the grinding body by grounding the upper and lower portions of the grinding body.

[0029] In addition, the feed pipe may be provided with a predetermined ionizer to supply ionized air while supplying the sulfide-based solid electrolyte to the inside of the grinding body.

[0030] Specific matters of other embodiments are included in the “Detailed Description” and “Drawings”.

[0031] The advantages and / or features of the present invention, and methods for achieving them, can be found by reference to the accompanying Figure 1 This will become clear from various embodiments described in detail later.

[0032] However, the present invention is not limited to the compositions of the embodiments disclosed below, but may be implemented in a variety of different forms. The embodiments disclosed in this specification are only provided to complete the disclosure of the present invention and to fully inform the ordinary technicians in the technical field to which the present invention belongs of the scope of the present invention. It should be known that the claims of the present invention are only defined by the scope of each claim. Beneficial Effects

[0033] According to the solution of the aforementioned technical problem, the present invention has the following effects.

[0034] The present invention can remove static electricity inside the grinding body by grounding the upper and lower parts of the grinding body, thereby preventing raw material particles (such as sulfide solid electrolyte) from polymerizing and adhering to the inner wall of the grinding body.

[0035] Thus, the particle size can be easily adjusted by removing static electricity inside the grinding body that realizes pulverization.

[0036] In addition, the present invention can set a specified ion generator (ionizer) on the feed pipe, and while supplying the raw material to the feed hole of the upper plate arranged inside the grinding body, it also supplies ionized air, thereby having the effect of improving the crushing efficiency and productivity, so that the raw material (such as sulfide solid electrolyte) will not accumulate on the upper plate due to static electricity. BRIEF DESCRIPTION OF THE DRAWINGS

[0037] Figure 1 This is a diagram schematically showing a conventional jet mill.

[0038] Figure 2 This is a diagram for explaining the process of pulverizing a raw material in a conventional jet mill.

[0039] Figure 3 It is a figure which shows schematically the grinding body in the jet mill of this invention.

[0040] Figure 4 This is a diagram showing an upper plate provided inside a grinding body of the jet mill of the present invention.

[0041] Figure 5 This is a diagram showing a lower plate provided at the lower part of the grinding body of the jet mill of the present invention.

[0042] Figure 6 This is a diagram showing a cover of a grinding body in the jet mill of the present invention.

[0043] Figure 7 The graph shows photographs and particle size analysis results comparing an upper plate inside a grinding body of a jet mill of the present invention (Example) and an upper plate inside a grinding body of a jet mill of the prior art (Comparative Example). Description of Reference Numerals

[0044] 10: Feeding Department

[0045] 12: Feed pipe

[0046] 14: Ion Generator

[0047] 20: Grinding body

[0048] 22: Upper board

[0049] 24: Lower plate

[0050] 24a: Air nozzle

[0051] 26: Lid

[0052] 26a: Grading wheel

[0053] 28: First product mobile tube

[0054] 30: Cyclone separator

[0055] 32: Second product mobile tube

[0056] 40: Bag filter

[0057] 50: Blower DETAILED DESCRIPTION

[0058] Hereinafter, the preferred embodiments of the static-eliminating air flow mill of the present invention and the pulverizing method of the sulfide solid electrolyte using the same will be described in detail according to the accompanying drawings. For reference, the terms and words used in this specification and claims should not be interpreted as limited to their conventional meanings or meanings in the dictionary, and the inventor should be based on the principle that the concepts of the terms can be appropriately defined in order to explain his own invention in the best way, and use the meanings and concepts that are consistent with the technical ideas of the present invention for interpretation. In addition, the embodiments described in this specification and the configuration shown in the accompanying drawings are only the most preferred embodiments of the present invention and do not represent the entire technical ideas of the present invention. Therefore, it should be understood that there may be a variety of equivalents and modifications that can replace them when this application is submitted.

[0059] Figure 3 It is a figure which shows schematically the grinding body in the jet mill of this invention.

[0060] The static-free air jet mill of the present invention is constructed as follows: when raw materials are fed from a feed section through a specified feed pipe 12 into a hollow grinding body 20, and the raw materials fed into the grinding body 20 are filled to a certain height or above, strong jet air is ejected from an air nozzle 24a disposed at the bottom of the grinding body 20, causing the raw materials to collide and be crushed.

[0061] In this case, the raw material may be a sulfide-based solid electrolyte.

[0062] The sulfide-based solid electrolyte described above is a type of inorganic solid electrolyte.

[0063] Inorganic solid electrolytes are generally classified into oxides and sulfides.

[0064] Sulfide solid electrolytes are being widely studied as promising materials in the development of a new generation of all-solid-state batteries. Like liquid electrolytes, the sulfide solid electrolytes have the advantages of high ionic conductivity, low mechanical deformability and low weight density.

[0065] When a raw material (such as the sulfide-based solid electrolyte) is put into the grinding body 20 , static electricity may be generated. Due to the ductility of the solid electrolyte, particles aggregate and adhere to the inner wall of the grinding body 20 .

[0066] Thus, the present invention can remove static electricity inside the grinding body 20 by grounding the upper and lower parts of the grinding body 20, thereby facilitating the adjustment of particle size and improving pulverization efficiency.

[0067] The grinding body 20 is in a hollow cylindrical shape, and one end of the feed pipe 12 is coupled to one side of the grinding body 20 so as to communicate with the inside of the grinding body 20 .

[0068] At the same time, a horizontally arranged upper plate 22 is provided on the upper side of the grinding body 20, a horizontally arranged lower plate 24 is provided on the lower side of the grinding body 20, and a cover 26 is provided at the open upper end of the grinding body 20 for sealing the upper part of the grinding body 20.

[0069] At the same time, a specified ionizer 14 is provided in the feed pipe 12 to supply the raw material to the feed hole of the upper plate 22 arranged on the upper side of the grinding body 20, and at the same time supply ionized air, so as to prevent the raw material from aggregating between particles due to static electricity from accumulating on the upper part of the upper plate 22.

[0070] Figure 4 This is a diagram showing an upper plate provided inside a grinding body of the jet mill of the present invention.

[0071] A horizontal upper plate 22 is provided on the upper side of the grinding body 20 .

[0072] At this time, the outer surface of the upper plate 22 can be in a shape corresponding to the inner surface of the grinding body 20. When the upper plate 22 is set inside the grinding body 20, the outer surface of the upper plate 22 and the inner surface of the grinding body 20 can be kept airtight.

[0073] For example, the upper plate 22 may be in a disk shape, and the interior of the grinding body 20 may be in a cylindrical shape.

[0074] In the upper plate 22 as described above, one or more feed holes 22a are formed in a vertically penetrating manner in the circumferential direction, and the raw material supplied from the feed pipe 12 is put into the feed hole 22a and filled in the grinding body 20 to a certain height.

[0075] When the interior of the grinding body 20 is filled with raw materials to a certain height or more, the raw materials are caused to collide with each other and crushed by the strong jet air ejected from the air nozzle 24a.

[0076] Such an upper plate 22 may be made of ceramic.

[0077] Figure 5 This is a diagram showing a lower plate provided at the lower part of the grinding body of the jet mill of the present invention.

[0078] A horizontally disposed concave (in a shape that slopes downward from the edge toward the inside) lower plate 24 is provided at the lower side of the inside of the grinding body 20 .

[0079] A plurality of air nozzles 24 a may be provided along the edge of the lower plate 24 as described above, the air nozzles 24 a are spaced apart and radially arranged, and the air jet ports of the air nozzles 24 a may be arranged toward the center of the lower plate 24 .

[0080] The raw material is fed into the grinding body 20 through the feed hole 22a formed in the upper plate 22, descends to the lower plate 24 and is filled into the grinding body 20 to a certain height. When the raw material is filled to above a certain height, the raw material particles are crushed due to the strong jet air ejected from the air nozzle 24a.

[0081] At this time, the lower plate 24 may be made of ceramic.

[0082] Figure 6 This is a diagram showing a cover of a grinding body in the jet mill of the present invention.

[0083] A cover 26 is provided at the open upper end of the grinding body 20 for sealing the upper portion of the grinding body 20 .

[0084] A classifying wheel 26 a may be provided on the inner side of the cover 26 as described above (a side facing the inside of the grinding body 20 when the cover 26 seals the grinding body 20 ).

[0085] The raw material particles crushed by the strong jet air ejected from the air nozzle 24a inside the grinding body 20 rise with the air flow, and when the size of the particles is below a certain size, they pass through the classification wheel 26a and then move to the product collection part.

[0086] In addition, when the size of the raw material particles is larger than a certain size, they fall again along the inner wall of the grinding body 20 to the lower part of the grinding body 20 and are crushed by the jet air.

[0087] Figure 7 The graph shows photographs and particle size analysis results comparing an upper plate inside a grinding body of a jet mill of the present invention (Example) and an upper plate inside a grinding body of a jet mill of the prior art (Comparative Example).

[0088] The ion generator 14 arranged in the feed pipe 12 is used to remove the static electricity of the supplied air. This is to prevent the static electricity of the raw materials put into the grinding body 20 from causing the raw material particles to aggregate and block the feed hole 22a of the upper plate 22, and to prevent such aggregated particles from accumulating on the upper plate 22.

[0089] When ionized air is supplied through the ion generator 14, the phenomenon that the raw materials are accumulated on the upper part of the upper plate 22 can be improved. Figure 7As shown in the upper right photograph (Example), it can be seen that the raw material is not deposited in the portion where ionized air is supplied.

[0090] Figure 7 The photograph on the upper left side of (comparative example) shows a state where the raw materials are accumulated on the upper plate, causing the feed hole to be blocked (as in the prior art).

[0091] When the raw materials are not accumulated on the upper part of the upper plate 22 as described above, the raw materials crushed at the lower part of the grinding body 20 can be smoothly moved (classified) by the classifying wheel 26a located at the upper part along the rising airflow, thereby improving the crushing efficiency and productivity.

[0092] at the same time, Figure 7 The lower part shows the particle size analyzer (PSA) results, which show the maximum particle size (D max ) was micronized from 22.00 μm (Comparative Example) to 13.08 μm (Example), and the yield (g / h) was significantly improved from 300 g / h (Comparative Example) to 600 g / h (Example).

[0093] The present invention described above is not limited to the aforementioned embodiments and drawings, and various substitutions, deformations and changes can be made without departing from the technical concept of the present invention, which is obvious to ordinary technicians in the technical field to which the present invention belongs.

Claims

1. A jet mill capable of removing static electricity, characterized in that: When the raw materials are fed from the feeding part through a predetermined feeding pipe into the hollow grinding body, and when the raw materials fed into the grinding body are filled to a certain height or above, the raw materials are collided and crushed by strong jet air ejected from the air nozzle provided in the grinding body. The jet mill removes static electricity inside the grinding body by grounding the upper and lower parts of the grinding body.

2. The jet mill capable of removing static electricity according to claim 1, characterized in that: A horizontally arranged concave lower plate is provided at the lower side of the interior of the grinding body, a plurality of air nozzles are arranged at intervals along the edge of the lower plate, and the air nozzles are arranged toward the center of the lower plate.

3. The jet mill capable of removing static electricity according to claim 2, characterized in that: The lower plate is made of ceramic.

4. The jet mill capable of removing static electricity according to claim 1, characterized in that: A cover is arranged at the open upper end of the grinding body, and a grading wheel is arranged on the inner side of the cover.

5. The jet mill capable of removing static electricity according to claim 1, characterized in that: A horizontally arranged upper plate is provided on the upper side of the grinding body, and one or more feed holes are formed in the upper plate in a vertically penetrating manner along the circumferential direction, and the raw material supplied from the feed pipe is put into the feed hole.

6. The jet mill capable of removing static electricity according to claim 5, characterized in that: The upper plate is made of ceramic.

7. The jet mill capable of removing static electricity according to claim 1, characterized in that: The feed pipe is provided with a predetermined ion generator, which supplies ionized air while supplying the raw material to the feed hole of the upper plate, so that the raw material is not accumulated on the upper plate.

8. A method for pulverizing a sulfide solid electrolyte using a jet mill capable of removing static electricity, characterized in that: The method utilizes a jet mill, in which, when a sulfide solid electrolyte is fed from a feed portion through a predetermined feed pipe into a hollow grinding body and the sulfide solid electrolyte fed into the grinding body is filled to a certain height or more, a strong jet of air is ejected from an air nozzle disposed at a lower portion of the grinding body to cause the sulfide solid electrolyte to collide with each other and be crushed, The jet mill removes static electricity inside the grinding body by grounding the upper part and the lower part of the grinding body.

9. The method for pulverizing a sulfide-based solid electrolyte using a jet mill capable of removing static electricity according to claim 8, characterized in that: A predetermined ion generator is provided in the feed pipe to supply sulfide-based solid electrolyte to the inside of the grinding body and also to supply ionized air.

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