KR102254336B1 - Method of Manufacturing Electrode Slurry for Secondary Battery Comprising Degassing Process at Atmospheric Pressure - Google Patents

Abstract

The present invention is a method for producing an electrode slurry for a secondary battery,
(a) mixing raw materials of the electrode slurry;
(b) storing and transferring the electrode slurry mixed in step (a);
(c) removing air bubbles in the electrode slurry, which is a gaseous component, by centrifugation of the electrode slurry at normal pressure, and sending the defoamed electrode slurry to a coater die; And
(d) circulating the electrode slurry remaining in the coating process from the coater die to the centrifugal separation of step (c);
It relates to a manufacturing method comprising a.

Description

[Method of Manufacturing Electrode Slurry for Secondary Battery Comprising Degassing Process at Atmospheric Pressure}

The present invention relates to a method of manufacturing an electrode slurry for a secondary battery including the process of defoaming at atmospheric pressure.

Due to the rapid increase in the use of fossil fuels, the demand for the use of alternative energy or clean energy is increasing, and as part of that, the fields that are most actively studied are the fields of power generation and storage using electrochemistry.

Currently, a secondary battery is a representative example of an electrochemical device that uses such electrochemical energy, and its use area is gradually expanding.

Meanwhile, in order to manufacture an electrode for a secondary battery, a process of coating and drying the electrode slurry on a current collector is performed. The electrode slurry is prepared by mixing an electrode active material, a binder, and a solvent, and during the mixing process, air bubbles in the electrode slurry are included.

In the process of coating and drying the electrode slurry containing air bubbles on the current collector, gas craters are formed as the air bubbles escape from the inside of the current collector, causing a defect in the electrode.

In order to prevent defective electrodes in which gas craters are formed, it is necessary to undergo a so-called degassing process to remove air bubbles in the electrode slurry. In order to perform the defoaming process, a method of stirring while applying a vacuum is generally used.

However, in the case of stirring by applying a vacuum, there is a problem that a long dead time occurs during the degassing process, so that continuous operation is impossible, and the overall efficiency of the electrode slurry manufacturing process is deteriorated.

In addition, when the degassing operation is performed by applying a vacuum, a problem occurs in that volatile components in the electrode slurry evaporate.

Accordingly, there is a high need for a technology capable of producing an electrode slurry through a continuous process without dead time and maintaining a volatile component in the electrode slurry without evaporation.

An object of the present invention is to solve the problems of the prior art and technical problems that have been requested from the past.

The inventors of the present application have conducted in-depth research and various experiments, and as will be described later, in the case of removing air bubbles in the electrode slurry, which is a gaseous component, by centrifugation of the electrode slurry at normal pressure, It was confirmed that the electrode slurry could be continuously produced, and the volatile component in the electrode slurry was also maintained without evaporation, and the present invention was completed.

Therefore, the method of manufacturing an electrode slurry for a secondary battery according to the present invention,

(a) mixing raw materials of the electrode slurry;

(b) storing and transferring the electrode slurry mixed in step (a);

(c) removing air bubbles in the electrode slurry, which is a gaseous component, by centrifugation of the electrode slurry at normal pressure, and sending the defoamed electrode slurry to a coater die; And

(d) circulating the electrode slurry remaining in the coating process from the coater die to the centrifugal separation of step (c);

It characterized in that it comprises a.

That is, in the process of removing air bubbles in the process (c), since vacuum is not applied, no dead time occurs, and an electrode slurry can be continuously manufactured. In addition, since no vacuum is applied, there is an effect that the volatile components in the electrode slurry are not evaporated and maintained.

In one specific example, raw materials of the electrode slurry may include an electrode active material, a binder, and a solvent. However, this is only an example, and it goes without saying that other additives such as a filler and a conductive material may be further included if necessary.

In one specific example, raw materials may be mixed using a mixer in the process (a), and in detail, the mixer includes a planetary for low-speed stirring and a homo-disper for high-speed stirring ( homo-disper) may be equipped with a mixer.

The mixer is capable of low-speed stirring and high-speed stirring, and thus the overall process efficiency can be improved by adjusting the stirring speed and time according to the composition and viscosity of the electrode slurry.

In one specific example, in the process (b), the electrode slurry may go through a storage tank and a transfer tank to store and transfer the electrode slurry. In this way, by passing through the storage tank and the transfer tank, even when a problem occurs in some manufacturing processes, the process can be performed using the electrode slurry stored in the tank, and thus the dead time can be further reduced.

In addition, a pump may be used in the process of transmitting the electrode slurry to the storage tank and the transfer tank, and the type of the pump is not particularly limited as long as a predetermined capacity can be transmitted.

In one specific example, the electrode slurry may be sent from the mixer to the storage tank using a diaphragm pump and then sent from the storage tank to the transfer tank, and the diaphragm pump has high energy efficiency and a transfer flow rate. Because of this, it may be suitable for sending electrode slurry to storage tanks and transfer tanks.

Meanwhile, the removal of air bubbles in the process (c) may be performed by a continuous defoaming machine based on centrifugal separation.

Specifically, the continuous defoaming machine may be continuously supplied with electrode slurry from a transfer tank without a dead time, and may transmit the continuously defoamed slurry without a dead time to a coater die.

The transfer tank may supply electrode slurry to a continuous defoaming machine using a controlled volume pump.

The metering pump does not have a large transfer flow rate, but does not generate pulsation, and thus can stably supply a predetermined amount of electrode slurry, and has an advantage that bubbles are less likely to occur during the transfer process of the electrode slurry. That is, in order for the continuous defoaming machine to continuously perform a defoaming process without dead time, it is very important to supply a quantitative amount of electrode slurry through a metering pump. In addition, when the metering pump is used, since bubbles are not generated during the transfer process, the process of removing bubbles in the continuous defoaming machine can be performed more easily.

In one specific example, the continuous defoaming device, the cylindrical chamber; A raw material supply unit for supplying electrode slurry to the cylindrical chamber; A rotating part located on the lower space of the cylindrical chamber and separating the gas component of the electrode slurry and the electrode slurry component by centrifugal separation by rotational application; A slurry discharge unit for discharging the defoamed electrode slurry stacked on the inner circumferential portion of the lower space of the cylindrical chamber as a result of the centrifugation by moving upward; And a gas discharge unit configured to pass upward through the center of the cylindrical chamber in order to discharge the gas collected in the central portion of the lower space of the cylindrical chamber as a result of the centrifugal separation.

That is, by centrifugal separation by rotational application of the rotating part, gas with a light weight is collected in the center of the cylindrical chamber, and the electrode slurry component with a heavy weight moves to the inner circumferential surface outside of the cylindrical chamber. Since the fuel is continuously supplied through the raw material supply unit, the defoamed electrode slurry is stacked on the inner circumferential surface of the cylindrical chamber by centrifugal separation and moves upward. When the electrode slurry moves upward and reaches the slurry discharge part, it is continuously discharged through the slurry discharge part.

Meanwhile, the collected gas component is discharged to the outside through a gas discharge unit having a structure penetrating upward through the center of the cylindrical chamber, and at this time, it is not necessary to discharge by applying a special vacuum. However, it is not intended to exclude promoting gas discharge by applying an atmospheric pressure slightly lower than normal pressure.

Specifically, the raw material supply unit may have a hollow structure through which the gas discharge unit penetrates the inner center, and may have a structure in which a raw material injection hole is formed at an upper end.

In addition, the slurry discharge unit may have a hollow structure through which the raw material supply unit penetrates the inner center, and a slurry discharge port is formed at an upper portion thereof.

Meanwhile, the rotation unit may apply rotation of 200 rpm to 2,000 rpm, and in this case, the viscosity of the electrode slurry may be 2,000 cps to 30,000 cps.

That is, when the electrode slurry has a relatively low viscosity, bubbles can be sufficiently removed even when a relatively low rotation is applied, and when the viscosity is relatively high, bubbles cannot be sufficiently removed unless a high rotation is applied.

Specifically, when the viscosity of the electrode slurry is 2,000 cps to 4,000 cps, the rotation unit may apply rotation of 800 rpm to 1,600 rpm, and in this case, the electrode slurry may include a negative active material.

In contrast, when the viscosity of the electrode slurry is 8,000 cps to 30,000 cps, the rotation unit may apply rotation of 1,600 rpm to 2,000 rpm, and in this case, the electrode slurry may include a positive electrode active material.

The higher the viscosity of the electrode slurry, the longer it takes for degassing. Therefore, in the case of the positive electrode slurry, it may be preferable to design the positive electrode slurry with a relatively large capacity compared to the negative electrode slurry in terms of process efficiency.

Meanwhile, between the continuous deaerator and the coater die, a supply tank may be additionally positioned in order to more stably supply the electrode slurry to the coater die. In this case, in order to prevent bubbles from occurring in the electrode slurry during the process of using the electrode slurry as a coater die in the supply tank, and to deliver an accurate capacity, a metering pump may be used.

The present invention also provides a system for manufacturing an electrode slurry for a secondary battery, the system comprising: a mixer for mixing raw materials of the electrode slurry; A pump for transferring the electrode slurry; A tank for storing the electrode slurry; A continuous deaerator for removing air bubbles in the electrode slurry, which is a gaseous component, by centrifugation of the electrode slurry at normal pressure; And a coater die for coating the defoamed electrode slurry on a current collector.

In one specific example, the pump may include a diaphragm pump and a metering pump, and the tank may include a storage tank, a transfer tank, and a supply tank.

In one specific example, the system sends the electrode slurry mixed from the mixer to a storage tank using a diaphragm pump, and sends the electrode slurry stored in the storage tank to a transfer tank using a diaphragm pump, and the continuous removal In the aeration process, electrode slurry is continuously supplied from the transfer tank through a metering pump without dead time, and the continuously defoamed slurry without dead time is sent to the coater die, and the electrode slurry remaining in the coating process is transferred from the coater die to the continuous deaerator. Can be circulated.

In this case, a supply tank may be additionally positioned between the continuous deaerator and the coater die.

The present invention also provides an electrode for a secondary battery including an electrode mixture layer formed by applying the electrode slurry degassed by the above method on the surface of a current collector.

In detail, the electrode mixture layer may not have a gas crater formed as air bubbles escape during the drying process of the electrode slurry.

The present invention also provides a secondary battery including the electrode.

Hereinafter, other components of the secondary battery will be described.

The secondary battery includes a positive electrode, a negative electrode, and a separator, and the positive electrode may be manufactured by coating, for example, a positive electrode mixture in which a positive electrode active material, a conductive material, and a binder are mixed on a positive electrode current collector. A filler may be further added to the positive electrode mixture.

The positive electrode current collector is generally manufactured to a thickness of 3 to 201 µm, and is not particularly limited as long as it has high conductivity without causing chemical changes to the battery. For example, stainless steel, aluminum, nickel, titanium , And one selected from among those surface-treated with carbon, nickel, titanium or silver on the surface of aluminum or stainless steel may be used, and in detail, aluminum may be used. The current collector may increase the adhesion of the positive electrode active material by forming fine irregularities on its surface, and various forms such as films, sheets, foils, nets, porous bodies, foams, and nonwoven fabrics are possible.

The positive electrode active material may include, for example, _{a layered compound such as lithium cobalt oxide (LiCoO 2} ) or lithium nickel oxide (LiNiO ₂ ), or a compound substituted with one or more transition metals; Lithium manganese oxides such as formula Li _1+x Mn _2-x O ₄ (wherein x is 0 to 0.33), LiMnO ₃ , LiMn ₂ O ₃ , and LiMnO _2; Lithium copper oxide (Li ₂ CuO ₂ ); Vanadium oxides such as LiV ₃ O ₈ , LiV ₃ O ₄ , V ₂ O ₅ , and Cu ₂ V ₂ O _7; Ni site-type lithium nickel oxide represented by the formula LiNi _1-x M _x O ₂ (here, M = Co, Mn, Al, Cu, Fe, Mg, B or Ga, and x = 0.01 to 0.3); Formula LiMn _2-x M _x O ₂ (where M = Co, Ni, Fe, Cr, Zn or Ta, and x = 0.01 to 0.1) or Li ₂ Mn ₃ MO ₈ (where M = Fe, Co, A lithium manganese composite oxide represented by Ni, Cu, or Zn); _{LiMn 2} O _{4 in} which part of Li in the formula is substituted with alkaline earth metal ions; Disulfide compounds; Fe ₂ (MoO ₄ ) ₃ and the like may be mentioned, but the present invention is not limited thereto.

The total content of the conductive material may be added in an amount of 0.1 to 3.0% by weight based on the total weight of the positive electrode mixture.

The binder contained in the positive electrode is a component that aids in bonding of the active material and the conductive material and bonding to the current collector, and is typically added in an amount of 0.1 to 3.0% by weight based on the total weight of the mixture including the positive electrode active material. Examples of such a binder include polyvinylidene fluoride, polyvinyl alcohol, carboxymethylcellulose (CMC), starch, hydroxypropylcellulose, regenerated cellulose, polyvinylpyrrolidone, tetrafluoroethylene, polyethylene , Polypropylene, ethylene-propylene-diene terpolymer (EPDM), sulfonated EPDM, styrene-butadiene rubber, fluorine rubber, and various copolymers.

The filler is selectively used as a component that suppresses the expansion of the positive electrode, and is not particularly limited as long as it is a fibrous material without causing chemical changes to the battery, and examples thereof include olefin-based polymers such as polyethylene and polypropylene; Fibrous materials such as glass fiber and carbon fiber are used.

On the other hand, the negative electrode may be manufactured by coating a negative electrode mixture including a negative electrode active material, a conductive material, and a binder on the negative electrode current collector, and a filler may be optionally further included therein.

The negative electrode current collector is not particularly limited as long as it has conductivity without causing chemical changes to the battery, for example, copper, stainless steel, aluminum, nickel, titanium, calcined carbon, copper, or stainless steel. Surface treatment with carbon, nickel, titanium, silver, etc., aluminum-cadmium alloy, etc. may be used. In addition, like the positive electrode current collector, it is possible to enhance the bonding strength of the negative electrode active material by forming fine irregularities on the surface thereof, and it may be used in various forms such as films, sheets, foils, nets, porous bodies, foams, and nonwoven fabrics.

In the present invention, the thickness of the negative electrode current collector may all be the same within the range of 3 to 201 μm, but may have different values in some cases.

The negative active material may include, for example, carbon such as non-graphitized carbon and graphite-based carbon; Li _x Fe ₂ O ₃ (0≤x≤1), Li _x WO ₂ (0≤x≤1), Sn _x Me _1-x Me' _y O _z (Me: Mn, Fe, Pb, Ge; Me' : Al, B, P, Si, elements of groups 1, 2, and 3 of the periodic table, halogen, metal complex oxides such as 0<x≦1;1≦y≦3;1≦z≦8); Lithium metal; Lithium alloy; Silicon-based alloys; Tin-based alloys; SnO, SnO ₂ , PbO, PbO ₂ , Pb ₂ O ₃ , Pb ₃ O ₄ , Sb ₂ O ₃ , Sb ₂ O ₄ , Sb ₂ O ₅ , GeO, GeO ₂ , Bi ₂ O ₃ , Bi ₂ O ₄ , and metal oxides such as _{Bi 2} O _5; Conductive polymers such as polyacetylene; Li-Co-Ni-based materials and the like can be used.

In one specific example, the porous substrate may be a polyolefin-based separation film commonly used in the art, for example, high-density polyethylene, low-density polyethylene, linear low-density polyethylene, ultra-high molecular weight polyethylene, polypropylene, polyethylene terephthalate (polyethyleneterephthalate), polybutyleneterephthalate, polyester, polyacetal, polyamide, polycarbonate, polyimide, polyetheretherketone , Polyethersulfone (polyethersulfone), polyphenylene oxide (polyphenyleneoxide), polyphenylene sulfidero (polyphenylenesulfidro), polyethylene naphthalene (polyethylenenaphthalene) It may be a sheet consisting of one or more selected from the group consisting of a mixture thereof.

The pore size and porosity of the porous substrate are not particularly limited, but the porosity may be in the range of 10 to 95%, and the pore size (diameter) may be in the range of 0.1 to 50 μm. When the pore size and porosity are less than 0.1 μm and 10%, respectively, it acts as a resistance layer, and when the pore size and porosity exceed 50 μm and 95%, it is difficult to maintain mechanical properties.

The electrolyte may be a lithium salt-containing non-aqueous electrolyte, and the lithium salt-containing non-aqueous electrolyte is composed of a non-aqueous electrolyte and a lithium salt, and as the non-aqueous electrolyte, a non-aqueous organic solvent, an organic solid electrolyte, an inorganic solid electrolyte, etc. are used. It is not limited to only.

As the non-aqueous organic solvent, for example, N-methyl-2-pyrrolidinone, propylene carbonate, ethylene carbonate, butylene carbonate, dimethyl carbonate, diethyl carbonate, gamma -Butylrolactone, 1,2-dimethoxyethane, tetrahydroxyfuran, 2-methyl tetrahydrofuran, dimethylsulfoxide, 1,3-dioxolone, formamide, dimethylformamide, dioxolone, acetonitrile , Nitromethane, methyl formate, methyl acetate, phosphate tryester, trimethoxy methane, dioxolone derivative, sulfolane, methyl sulfolane, 1,3-dimethyl-2-imidazolidinone, propylene carbonate derivative, Aprotic organic solvents such as tetrahydrofuran derivatives, ethers, methyl pyropionate, and ethyl propionate may be used.

Examples of the organic solid electrolyte include polyethylene derivatives, polyethylene oxide derivatives, polypropylene oxide derivatives, phosphate ester polymers, poly agitation lysine, polyester sulfide, polyvinyl alcohol, polyvinylidene fluoride, ions A polymerization agent or the like containing an active dissociation group may be used.

As the inorganic solid electrolyte, for example, Li ₃ N, LiI, Li ₅ NI ₂ , Li ₃ N-LiI-LiOH, LiSiO ₄ , LiSiO ₄ -LiI-LiOH, Li ₂ SiS ₃ , Li ₄ SiO ₄ , Nitrides, halides, and sulfates of Li such as Li ₄ SiO ₄ -LiI-LiOH and Li ₃ PO ₄ -Li ₂ S-SiS _{2 may be used.}

The lithium salt is a material soluble in the non-aqueous electrolyte, for example, LiCl, LiBr, LiI, LiClO ₄ , LiBF ₄ , LiB ₁₀ Cl ₁₀ , LiPF ₆ , LiCF ₃ SO ₃ , LiCF ₃ CO ₂ , LiAsF ₆ , LiSbF _{6 , LiAlCl 4} , CH ₃ SO ₃ Li, (CF ₃ SO ₂ ) ₂ NLi, lithium chloroborane, lithium lower aliphatic carboxylic acid, lithium 4 phenyl borate, imide, and the like may be used.

In addition, in the non-aqueous electrolyte, for the purpose of improving charge/discharge properties and flame retardancy, for example, pyridine, triethylphosphite, triethanolamine, cyclic ether, ethylene diamine, n-glyme, hexaphosphate triamide, Nitrobenzene derivatives, sulfur, quinone imine dyes, N-substituted oxazolidinone, N,N-substituted imidazolidine, ethylene glycol dialkyl ether, ammonium salt, pyrrole, 2-methoxy ethanol, aluminum trichloride, etc. may be added. have. In some cases, in order to impart non-flammability, a halogen-containing solvent such as carbon tetrachloride and ethylene trifluoride may be further included, and carbon dioxide gas may be further included to improve high-temperature storage characteristics, and FEC (Fluoro-Ethylene Carbonate), PRS (Propene sultone), and the like may be further included.

In one specific example, _{lithium salts such as LiPF 6} , LiClO ₄ , LiBF ₄ , LiN(SO ₂ CF ₃ ) ₂ are used in the cyclic carbonate of EC or PC as a highly dielectric solvent and DEC, DMC or EMC as a low viscosity solvent. The lithium salt-containing non-aqueous electrolyte can be prepared by adding it to a mixed solvent of linear carbonate.

The present invention also provides a battery pack including such a secondary battery as a unit cell, and a device including such a battery pack as a power source.

The device includes, for example, a notebook computer, a netbook, a tablet PC, a mobile phone, an MP3, a wearable electronic device, a power tool, an electric vehicle (EV), and a hybrid electric vehicle (HEV). , Plug-in Hybrid Electric Vehicle (PHEV), electric bicycle (E-bike), electric scooter (E-scooter), electric golf cart (electric golf cart), or power storage system However, of course, it is not limited to these only.

Since the structure and manufacturing method of such a device are well known in the art, detailed descriptions thereof are omitted herein.

As described above, in the method of manufacturing an electrode slurry for a secondary battery according to the present invention, air bubbles in the electrode slurry, which is a gaseous component, are removed by centrifugation of the electrode slurry at normal pressure, and the defoamed electrode slurry is applied to a coater die. Including the process of sending to the electrode, the electrode slurry can be continuously manufactured without dead time, and the volatile component in the electrode slurry is maintained without evaporation.

In addition, a gas crater is not formed when bubbles escape from the electrode mixture layer, so that a defect rate during electrode manufacturing can be reduced.

1 is a photograph of a gas crater formed in an electrode mixture layer;
Figure 2 is an enlarged photograph of the gas crater of Figure 1;
3 is a schematic diagram showing a method of manufacturing an electrode slurry for a secondary battery according to an embodiment of the present invention;
4 is a vertical cross-sectional view schematically showing a continuous defoaming machine according to an embodiment of the present invention.

Hereinafter, it will be described with reference to the drawings according to an embodiment of the present invention, but this is for an easier understanding of the present invention, and the scope of the present invention is not limited thereto.

3 is a schematic diagram showing a method of manufacturing an electrode slurry for a secondary battery according to an embodiment of the present invention.

Referring to FIG. 3, in the manufacturing method according to the present invention, an electrode slurry is manufactured using a mixer, a storage tank, a transfer tank, a continuous defoaming machine, a supply tank, a coater die, two diaphragm pumps, and two metering pumps.

Specifically, an electrode active material, a binder, and a solvent, which are raw materials of an electrode slurry, are added to a mixer and mixed. The electrode slurry mixed by the mixer contains air bubbles therein.

The mixer is equipped with a planetary for low-speed stirring and a homo-disper for high-speed stirring, and through this, low-speed stirring and high-speed stirring are possible, and stirring according to the composition and viscosity of the electrode slurry Adjust the speed and stirring time.

For storage and transfer, the electrode slurry passes through the storage tank and the transfer tank, and thus, by passing through the storage tank and the transfer tank, it is possible to continuously supply the electrode slurry without dead time even when a problem occurs in some manufacturing processes.

The process of transferring the electrode slurry from the mixer to the storage tank is performed through a diaphragm pump having high energy efficiency and a large transfer flow rate, and a process of transferring the electrode slurry from the storage tank to the transfer tank is also performed through a diaphragm pump.

Thereafter, the electrode slurry stored in the transfer tank is sent to a continuous deaerator using a metering pump, and the continuous deaerator receives electrode slurry from the transfer tank continuously without dead time, and continuously degassed slurry without dead time. Send it to the supply tank.

The continuous defoaming machine receives a fixed amount of electrode slurry through a metering pump in order to continuously perform a defoaming process without dead time. In addition, when the metering pump is used, bubbles are not generated during the transfer process, so that the process of removing the bubbles in the continuous defoaming machine is easier.

The slurry sent from the continuous defoaming machine is temporarily stored in a supply tank, and sent back to the coater die through a metering pump.

For uniform coating in the coater die, it is set to receive an excessive amount of electrode slurry, and thus, the electrode slurry remaining in the coating process is circulated from the coater die to a continuous defoaming machine and undergoes a defoaming process once again.

Through this process, the electrode slurry can be continuously manufactured without dead time, and since the process is performed at normal pressure, volatile components in the electrode slurry can be maintained without evaporation.

4 schematically shows a vertical cross-sectional view of a continuous defoaming machine according to an embodiment of the present invention.

Referring to FIG. 4, the continuous deaerator 100 includes a cylindrical chamber 110, a raw material supply unit 120, a rotating unit 130, a slurry discharge unit 140, and a gas discharge unit 150.

Specifically, the electrode slurry is supplied to the cylindrical chamber 110 through the raw material supply unit 120. The electrode slurry injected through the raw material supply unit 120 moves to the rotating unit 130 located on the lower space of the cylindrical chamber 110 according to the arrow.

The rotating part 130 applies rotation to the electrode slurry to centrifuge the gas component and the defoamed electrode slurry. That is, by centrifugal separation by rotational application of the rotating part 130, the gas having a light weight is collected in the center of the cylindrical chamber 110, and the degassed electrode slurry component having a heavy weight moves to the inner circumferential surface of the cylindrical chamber 110. do.

The defoamed electrode slurry component is deposited on the inner circumferential surface of the cylindrical chamber 110 and moves upward along the inner circumferential surface. The defoamed electrode slurry thus moved upward is continuously discharged through the slurry discharge unit 140.

The gas collected in the center of the cylindrical chamber 110 is discharged to the outside through a gas discharge unit 150 formed in a structure that penetrates upward through the center of the cylindrical chamber 110.

In this case, the raw material supply unit 120 has a hollow structure through which the gas discharge unit 150 passes through the inner center, and the raw material injection hole 121 is formed at the upper portion.

The slurry discharge unit 140 has a hollow structure through which the raw material supply unit 120 penetrates the inner center, and a slurry discharge port 141 is formed at an upper portion thereof.

Although the above has been described with reference to the embodiments of the present invention, a person of ordinary skill in the field to which the present invention belongs will be able to perform various applications and modifications within the scope of the present invention based on the above contents.

Claims (21)

As a method of manufacturing an electrode slurry for a secondary battery,
(a) mixing raw materials of the electrode slurry;
(b) storing and transferring the electrode slurry mixed in step (a);
(c) removing air bubbles in the electrode slurry, which is a gaseous component, by centrifugation of the electrode slurry at normal pressure, and sending the defoamed electrode slurry to a coater die; And
(d) circulating the electrode slurry remaining in the coating process from the coater die to the centrifugal separation of step (c); Including,
The removal of air bubbles in the process (c) is performed by a continuous defoaming machine based on centrifugation,
The continuous defoaming group,
Cylindrical chamber;
A raw material supply unit for supplying electrode slurry to the cylindrical chamber;
A rotating part located on the lower space of the cylindrical chamber and separating the gas component of the electrode slurry and the electrode slurry component by centrifugal separation by rotational application;
A slurry discharge unit for discharging the defoamed electrode slurry stacked on the inner circumferential portion of the lower space of the cylindrical chamber as a result of the centrifugation by moving upward; And
A gas discharge unit configured to penetrate upward through the center of the cylindrical chamber in order to discharge the gas collected in the central portion of the lower space of the cylindrical chamber as a result of the centrifugal separation; Including,
When the viscosity of the electrode slurry is 2,000 cps to 30,000 cps, the rotating part applies rotation of 200 rpm to 2,000 rpm,
In the process (b), the electrode slurry is passed through a storage tank and a transfer tank for storage and transfer of the electrode slurry, and the electrode slurry is transferred from the mixer to the storage tank using a diaphragm pump, and then again from the storage tank. Sent to the transfer tank,
The continuous defoaming machine receives electrode slurry from a transfer tank continuously without dead time, and sends the continuously defoamed slurry without dead time to a coater die, and the transfer tank uses a controlled volume pump to provide electrode slurry. A manufacturing method, characterized in that supplying to the continuous defoaming machine. The method of claim 1, wherein the raw materials of the electrode slurry include an electrode active material, a binder, and a solvent. The manufacturing method according to claim 1, wherein the raw materials are mixed using a mixer in the step (a). The manufacturing method according to claim 3, wherein the mixer is provided with a planetary for low-speed stirring and a homo-disper for high-speed stirring. delete delete delete delete delete delete The manufacturing method according to claim 1, wherein the raw material supply unit has a hollow structure through which the gas discharge unit penetrates the inner center, and a raw material injection hole is formed at an upper end thereof. The method of claim 1, wherein the slurry discharge part has a hollow structure through which the raw material supply part penetrates the inner center, and a slurry discharge port is formed at an upper end thereof. The method of claim 1, wherein the continuous defoaming machine receives electrode slurry from the transfer tank continuously without dead time, and sends the continuously defoamed slurry without dead time to the coater die,
The transfer tank supplies electrode slurry to a continuous defoaming machine using a controlled volume pump,
The continuous defoaming group,
Cylindrical chamber;
A raw material supply unit for supplying electrode slurry to the cylindrical chamber;
A rotating part located on the lower space of the cylindrical chamber and separating the gas component of the electrode slurry and the electrode slurry component by centrifugal separation by rotational application;
A slurry discharge unit for discharging the defoamed electrode slurry stacked on the inner circumferential portion of the lower space of the cylindrical chamber as a result of the centrifugation by moving upward; And
A gas discharge unit configured to penetrate upward through the center of the cylindrical chamber in order to discharge the gas collected in the central portion of the lower space of the cylindrical chamber as a result of the centrifugal separation; Including,
The raw material supply unit has a hollow structure through which the gas discharge unit passes through the inner center, and the raw material injection port is formed at the upper end,
The slurry discharging unit has a hollow structure through which the raw material supply unit penetrates the inner center, and a slurry discharging port is formed at an upper end thereof.
The manufacturing method according to claim 1, wherein a supply tank is additionally located between the continuous defoaming unit and the coater die. As a system for manufacturing an electrode slurry for a secondary battery,
A mixer for mixing raw materials of the electrode slurry;
A pump for transferring the electrode slurry;
A tank for storing the electrode slurry;
A continuous deaerator for removing air bubbles in the electrode slurry, which is a gaseous component, by centrifugation of the electrode slurry at normal pressure; And
A coater die coating the defoamed electrode slurry on a current collector; Including,
The continuous defoaming group,
Cylindrical chamber;
A raw material supply unit for supplying electrode slurry to the cylindrical chamber;
A rotating part located on the lower space of the cylindrical chamber and separating the gas component of the electrode slurry and the electrode slurry component by centrifugal separation by rotational application;
A slurry discharge unit for discharging the defoamed electrode slurry stacked on the inner circumferential portion of the lower space of the cylindrical chamber as a result of the centrifugation by moving upward; And
A gas discharge unit configured to penetrate upward through the center of the cylindrical chamber in order to discharge the gas collected in the central portion of the lower space of the cylindrical chamber as a result of the centrifugal separation; Including,
When the viscosity of the electrode slurry is 2,000 cps to 30,000 cps, the rotation unit applies a rotation of 200 rpm to 2,000 rpm,
Sending the electrode slurry mixed from the mixer to a storage tank using a diaphragm pump,
The electrode slurry stored in the storage tank is sent to a transfer tank using a diaphragm pump,
The continuous defoaming machine receives electrode slurry from a transfer tank through a metering pump continuously without dead time, and sends the continuously defoamed slurry without dead time to a coater die,
A system characterized in that the electrode slurry remaining in the coating process is circulated from the coater die to a continuous deaerator. delete delete 16. The system of claim 15, further comprising a feed tank positioned between the continuous defoaming unit and the coater die. delete delete delete

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