Flow rate control device and method for coating multi-zone double layer

Abstract

An embodiment of the present invention relates to a flow rate control device and method for coating a multi-zone double layer, the flow rate control device comprising: a plurality of slit molds distributed as upper and lower layers and configured to coat an electrode with a slurry; a pump configured to supply slurry from the reservoir to each of the upper layer and the lower layer; a valve at the plurality of slit molds and configured to divert the slurry supplied from the pump and supply the diverted slurry to the plurality of slit molds; a flow meter configured to measure a flow rate of the slurry supplied to the plurality of slit molds; and a processor configured to control the pump and the valve to control a coating amount of the electrode based on the flow rate of the slurry measured by the flow meter.

Description

Technical Field

[0001] Aspects of embodiments of the present invention relate to a flow rate control device and a flow rate control method. Background Art

[0002] Unlike primary batteries that cannot be recharged, secondary batteries are batteries that can be charged and discharged. Low-capacity secondary batteries are used in small portable electronic devices such as smartphones, feature phones, laptop computers, digital cameras, and video cameras, and high-capacity secondary batteries are widely used as drive power sources and power storage batteries for electric motors in hybrid vehicles and electric vehicles. Such secondary batteries include an electrode assembly provided with a positive electrode and a negative electrode, a case for accommodating the electrode assembly, electrode terminals connected to the electrode assembly, and the like.

[0003] Manufacturing such secondary batteries involves a process of coating positive and negative electrode substrates with an active material slurry.

[0004] The electrodes can be coated by the following method: using a pump to supply the slurry contained in a storage tank to a slot die, and coating the electrodes with the slurry discharged through the slot die.

[0005] When the coated electrodes pass through a drying furnace, the coated electrodes (such as electrode plates) are dried, and the coating quality of the electrode plates passing through the drying furnace is measured and managed in the width direction and the moving direction of the electrodes using the load level per unit area (hereinafter referred to as L / L) measured by a densitometer.

[0006] However, in a system for coating electrodes, when increasing the width of the slot die to improve productivity, a large number of coated rows can be produced simultaneously, but there are problems of deteriorated coating quality, such as an increase in the dispersion of L / L per unit area in the width direction.

[0007] In addition, in a system for coating electrodes, when the coating thickness is increased, there are problems of deteriorated electrode quality, such as a decrease in the bonding strength between the dried electrode and the slurry, and a decrease in ionic conductivity due to the concentration of the binder in the upper part.

[0008] Therefore, a method for improving both electrode quality and productivity is needed.

[0009] The above information described in the background art of the present invention is only for helping to understand the background of the present invention, and may also include information not included in conventional technologies. Summary of the Invention

[0010] Aspects of embodiments of the present invention relate to a flow rate control device and a flow rate control method for coating a multi-division double layer, and the flow rate control device controls the flow rate of a slurry for coating electrodes.

[0011] Aspects of some embodiments of the present invention are directed to providing a flow rate control device and method for coating a multi-zone bilayer, in which the bilayer is divided into a plurality of parts, and the flow rate control device or method controls the flow rate of a slurry to adjust the coating amount of an electrode of a secondary battery and improve the coating quality.

[0012] However, the technical objectives to be solved by the present invention are not limited to the above objectives, and those skilled in the art will clearly understand other objectives not described above through the following description.

[0013] According to some embodiments of the present disclosure, there is provided a flow rate control device for coating a multi-zone bilayer, including: a plurality of slot dies, which are assigned to an upper layer and a lower layer and are configured to coat an electrode with a slurry; a pump configured to supply the slurry from a storage tank to each of the upper layer and the lower layer; a valve at the plurality of slot dies and configured to split the slurry supplied from the pump and supply the split slurry to the plurality of slot dies; a flow meter configured to measure the flow rate of the slurry supplied to the plurality of slot dies; and a processor configured to control the pump and the valve based on the flow rate of the slurry measured by the flow meter to control the coating amount of the electrode.

[0014] In some embodiments, the valve is provided as a plurality of valves; the slurry to be supplied to the upper layer is supplied to the plurality of slot dies of the upper layer through the pump; and the slurry to be supplied to the lower layer is supplied to the plurality of slot dies of the lower layer through the pump.

[0015] In some embodiments, the pump includes: a first pump configured to supply the slurry contained in the storage tank to the upper layer; and a second pump configured to supply the slurry contained in the storage tank to the lower layer.

[0016] In some embodiments, the processor is configured to receive, using the flow meter, the flow rate for each of the plurality of slot dies, and compare the sum of the flow rates for the upper layer with the sum of the flow rates for the lower layer; and in response to the ratio between the sum of the flow rates for the upper layer and the sum of the flow rates for the lower layer not reaching a target value, the processor is configured to control the revolutions per minute (RPM) of the pump to adjust the supply amount of the slurry supplied to either the upper layer or the lower layer.

[0017] In some embodiments, the processor is configured to compare the flow rates for the plurality of slot dies in the lower layer; and in response to a difference in the flow rates for the plurality of slot dies existing between rows, the processor is configured to control the valve to reduce the difference in the flow rates of the slurry for the plurality of slot dies.

[0018] In some embodiments, the flow rate control device further includes a densitometer configured to measure the thickness of the coating amount of the electrode.

[0019] In some embodiments, in response to the coating amount of the electrode measured by the densitometer not meeting the target coating amount, the processor is configured to control the pump to adjust the supply amount of the slurry.

[0020] In some embodiments, the processor is configured to calculate the coating amount difference for a plurality of slot dies measured by the densitometer between rows; and in response to there being a coating amount difference for the plurality of slot dies between rows, the processor is configured to control the valve to adjust the flow rate of the slurry supplied to the plurality of slot dies.

[0021] In some embodiments, the processor is configured to calculate the average value of the flow rates for a plurality of slot dies of a row measured by the flowmeter, calculate the change amount by subtracting the target flow rate from the average value of the flow rates, and set the change amount of the revolutions per minute (RPM) of the pump according to the range of the change amount.

[0022] In some embodiments, the processor is configured to calculate the total average value of the flow rates measured by the flowmeter, calculate the deviation using the value obtained by subtracting the flow rate of the row from the total average value, and adjust the opening degree of the valve according to the magnitude of the deviation.

[0023] According to some embodiments of the present invention, there is provided a flow rate control method for coating a multi-partition double layer, including: supplying a slurry for coating an electrode from a storage tank to a plurality of slot dies of an upper layer and a lower layer through a pump; diverting the slurry supplied from the pump through a valve and supplying the diverted slurry to the plurality of slot dies of the upper layer and the lower layer; measuring the flow rate of the slurry supplied to the plurality of slot dies through a flowmeter; and changing the flow rate of the slurry supplied to any one of the plurality of slot dies by the processor by controlling at least any one of the pump and the valve based on the flow rate of the slurry measured by the flowmeter.

[0024] In some embodiments, the supply of the slurry includes: supplying the slurry contained in the storage tank to the upper layer through a first pump; and supplying the slurry contained in the storage tank to the lower layer through a second pump.

[0025] In some embodiments, the diversion of the slurry and the supply of the diverted slurry include: diverting the slurry to be supplied to the upper layer through a valve installed at the upper layer and supplying the diverted slurry to a plurality of slot dies provided in the upper layer; and diverting the slurry to be supplied to the lower layer through a valve installed at the lower layer and supplying the diverted slurry to a plurality of slot dies provided in the lower layer.

[0026] In some embodiments, changing the flow rate of the slurry includes: receiving, via a flow meter, each of the flow rates for a plurality of slot dies, and comparing the sum of the flow rates for the upper layer with the sum of the flow rates for the lower layer; determining whether the ratio between the sum of the flow rates for the upper layer and the sum of the flow rates for the lower layer reaches a target value based on the comparison result; and in response to the ratio between the sum of the flow rates for the upper layer and the sum of the flow rates for the lower layer not reaching the target value, controlling the revolutions per minute (RPM) of the pump to adjust the supply amount of the slurry supplied to either the upper layer or the lower layer.

[0027] In some embodiments, changing the flow rate of the slurry includes: comparing the flow rates for a plurality of slot dies at the lower layer; and in response to a flow rate difference existing between rows of the plurality of slot dies, controlling a valve to reduce the flow rate difference of the slurry for the plurality of slot dies.

[0028] In some embodiments, changing the flow rate of the slurry includes: calculating an average value of the flow rates for a row of a plurality of slot dies measured by a flow meter; calculating a change amount by subtracting a target flow rate from the average value of the flow rates; and setting a change amount of the revolutions per minute (RPM) of the pump according to the range of the change amount.

[0029] In some embodiments, changing the flow rate of the slurry includes: calculating a total average value of the flow rates measured by a flow meter; calculating a deviation using a value calculated by subtracting the flow rate for a row from the total average value; and adjusting the opening degree of a valve according to the magnitude of the deviation.

[0030] In some embodiments, the flow rate control method further includes measuring, via a densitometer, the thickness of the coating amount for an electrode.

[0031] In some embodiments, the flow rate control method further includes: comparing, via a processor, the coating amount for an electrode measured by a densitometer with a target coating amount; and in response to the coating amount of the electrode not meeting the target coating amount, controlling, via the processor, a pump to adjust the supply amount of the slurry.

[0032] In some embodiments, the flow rate control method further includes: calculating, via a processor, the coating amount difference for a plurality of slot dies measured by a densitometer between rows; and in response to a coating amount difference for a plurality of slot dies existing between rows, controlling, via the processor, a valve to adjust the flow rate of the slurry supplied to the plurality of slot dies. BRIEF DESCRIPTION OF THE DRAWINGS

[0033] The following drawings attached to this specification illustrate embodiments of the present invention, and further describe aspects and features of the present invention as well as the detailed description of the present invention. Therefore, the present invention should not be construed as being limited to the drawings:

[0034] Figure 1 andFigure 2 are a schematic view and a cross-sectional view showing a cylindrical battery according to some embodiments of the present invention;

[0035] Figure 3 is a schematic block diagram showing a flow rate control device for coating a multi-zone bilayer according to some embodiments of the present invention;

[0036] Figure 4 is a diagram showing the configuration of a system for coating a multi-zone bilayer according to some embodiments of the present invention;

[0037] Figure 5 is a diagram showing the operation process of a flow rate control device for coating a multi-zone bilayer according to some embodiments of the present invention;

[0038] Figure 6 is a flowchart showing a flow rate control method for coating a multi-zone bilayer according to some embodiments of the present invention;

[0039] Figure 7 is a table showing the pump control standard values of a flow rate control device for coating a multi-zone bilayer according to some embodiments of the present invention;

[0040] Figure 8 is a table showing the standard values of the valve opening degrees of a flow rate control device for coating a multi-zone bilayer according to some embodiments of the present invention;

[0041] Figure 9A and Figure 9B shows a graph of the deviation of the flow rate and thickness of the operation of the pump of a flow rate control device for coating a multi-zone bilayer according to some embodiments in accordance with the present invention; and

[0042] Figure 10A and Figure 10B shows a graph of the flow rate control result of a flow rate control device for coating a multi-zone bilayer according to some embodiments of the present invention. Detailed embodiments

[0043] Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings. First, the terms and words used in this specification and claims should not be construed as limited to the common meanings or meanings in the dictionary, but should be interpreted as having meanings and concepts consistent with the technical scope of the present invention based on the fact that the inventor has appropriately defined the concepts of the terms in order to describe the principles of the present invention in the best way. Therefore, since the embodiments described in this specification and the components shown in the drawings are only some exemplary embodiments and do not represent the entire technical scope of the present invention, it should be understood that various equivalents or modifications of the alternative exemplary embodiments may be available at the time of filing this application. In addition, the terms "comprising", "including", "comprising... of" and / or "including... of" used herein specify the existence of some of the stated shapes, quantities, steps, operations, components, elements and / or groups thereof, but do not exclude the existence or addition of one or more other shapes, quantities, operations, components, elements and / or groups thereof. In addition, when describing the embodiments of the present invention, the term "may" or "may be" may include "one or more embodiments of the present invention".

[0044] In addition, for ease of understanding of the present invention, the drawings are not drawn to scale, and the dimensions of some components may be exaggerated. In addition, in different embodiments, the same reference numerals may be assigned to the same elements.

[0045] The statement that "two comparison objects are the same" means that "the two comparison objects are actually the same". Therefore, the term "actually the same" includes cases where there are deviations considered to be at a low level in the art (for example, a deviation of 5% or less). In addition, the description that "some parameters are consistent within a certain region" may mean that "some parameters are consistent from an average perspective".

[0046] Although terms such as first, second, etc. may be used to describe various elements, the elements are not limited by such terms. These terms are only used to distinguish one element from another, and unless otherwise specifically described, the first element may also be the second element.

[0047] Throughout the specification, unless otherwise specifically described, each element may be single or multiple.

[0048] The case where the first element is disposed "above (or below)" or "on (or under)" the second element may include the case where the first element is disposed in contact with the upper (or lower) surface of the second element, or the case where a third element is interposed between the first element and the second element disposed above (or below) the first element.

[0049] It should be understood that when a first element is referred to as being "connected", "coupled" or "joined" to a second element, although the first element may be directly connected or joined to the second element, it should be understood that a third element may be interposed therebetween, or the elements may be connected, coupled or joined through other elements. In addition, when a first portion is referred to as being "electrically connected" to a second portion, it includes not only the case where the first portion is "directly connected" to the second portion, but also the case where the first portion is "connected" to the second portion and a third element is interposed therebetween.

[0050] As used herein, the term "and / or" includes any and all combinations of one or more of the associated listed items. For example, the expression "A and / or B" means A, B, or A and B. Expressions such as "one or more" and "at least one of" when preceding a list of elements modify the entire list of elements, rather than individual elements in the list. For example, the expressions "one or more of A, B, and C", "at least one of A, B, or C", "at least one of A, B, and C", and "at least one selected from the group consisting of A, B, and C" mean only A, only B, only C, both A and B, both A and C, both B and C, or all of A, B, and C.

[0051] In addition, when "may" is used in describing embodiments of the inventive concept, it refers to "one or more embodiments of the inventive concept". In addition, the term "exemplary" is intended to refer to an example or instance.

[0052] Figure 1 and Figure 2 are a schematic view and a cross-sectional view, respectively, showing a cylindrical battery according to some embodiments of the present invention.

[0053] Referring to Figure 1 and Figure 2 , a cylindrical lithium-ion secondary battery 100 according to various embodiments of the present invention may include a cylindrical can 110, an electrode assembly 120, and a cap assembly 140. In addition, in some cases, the cylindrical lithium-ion secondary battery 100 may further include a center pin 130. In addition, in the secondary battery 100 according to an embodiment of the present invention, since the cap assembly 140 is used to interrupt current, the cap assembly 140 may be referred to as a current interrupt device in some cases.

[0054] The cylindrical can 110 may include a substantially circular bottom 111 and a cylindrical sidewall 112 extending upward from a circumferential portion of the bottom 111 to a set or predetermined length. During the manufacturing process of the secondary battery, the upper portion of the cylindrical can 110 is open. Thus, during the assembly process of the secondary battery, the electrode assembly 120, the center pin 130, and the electrolyte may be inserted into the cylindrical can 110. For example, the cylindrical can 110 may be formed of steel, stainless steel, aluminum, aluminum alloy, and / or equivalent materials, but is not limited thereto.

[0055] In addition, the cylindrical can 110 may include an inwardly recessed beading part 113 disposed below the lid assembly 140 and an inwardly curved hemming part 114 disposed above the lid assembly 140, such that the lid assembly 140 does not escape outward. Here, the beading part 113 and the hemming part 114 are disposed around the lid assembly 140.

[0056] The electrode assembly 120 may be accommodated in the cylindrical can 110. The electrode assembly 120 may include: a negative electrode plate 121, in which a negative current collector plate is coated with a negative electrode active material (e.g., graphite, carbon, or the like); a positive electrode plate 122, in which a positive current collector plate is coated with a positive electrode active material (e.g., a transition metal oxide such as LiCoO 2 、LiNiO 2 、LiMn 2 O 4 or the like); and a separator 123 disposed between the negative electrode plate 121 and the positive electrode plate 122 to prevent or greatly reduce the possibility of a short circuit and to allow only lithium ions to move. In addition, the negative electrode plate 121, the positive electrode plate 122, and the separator 123 may be wound in a substantially cylindrical shape. Here, for example, the negative current collector plate may be made of copper (Cu) foil and / or the like, the positive current collector plate may be formed of aluminum (Al) foil and / or the like, and the separator may be formed of polyethylene (PE), polypropylene (PP), and / or the like, but the present invention is not limited thereto.

[0057] In addition, a negative electrode tab 124 protruding downward to extend to a set or predetermined length may be welded to the negative electrode plate 121, and a positive electrode tab 125 protruding upward to extend to a set or predetermined length may be welded to the positive electrode plate 122, but the reverse is possible. In addition, for example, the negative electrode tab 124 may be formed of copper (Cu), nickel (Ni), and / or the like, and the positive electrode tab 125 may be formed of aluminum (Al) and / or the like, but the present invention is not limited thereto.

[0058] In addition, the negative electrode tab 124 of the electrode assembly 120 may be welded to the bottom portion 111 of the cylindrical can 110. Accordingly, the cylindrical can 110 may operate as a negative electrode. However, conversely, the positive electrode tab 125 may be welded to the bottom portion 111 of the cylindrical can 110, and in this example, the cylindrical can 110 may operate as a positive electrode.

[0059] In addition, a first insulating plate 126, which is coupled to the cylindrical can 110 and in which a first hole 126a is formed at its center and a second hole 126b is formed at its outer side, can be interposed between the electrode assembly 120 and the bottom portion 111. The first insulating plate 126 is used to prevent the electrode assembly 120 from making electrical contact with the bottom portion 111 in the cylindrical can 110, or to significantly reduce the possibility of such electrical contact. In some examples, the first insulating plate 126 is used to prevent the positive electrode plate 122 in the electrode assembly 120 from making electrical contact with the bottom portion 111, or to significantly reduce the possibility of such electrical contact. Here, when a large amount of gas is generated due to an abnormality of the secondary battery, the first hole 126a is used to allow the gas to quickly move upward through the center pin 130, and the second hole 126b is used to allow the negative electrode tab 124 to pass through it and be welded to the bottom portion 111.

[0060] In addition, a second insulating plate 127, which is coupled to the cylindrical can 110 and in which a first hole 127a is formed at its center and a plurality of second holes 127b are formed at its outer side, can be interposed between the electrode assembly 120 and the lid assembly 140. The second insulating plate 127 is used to prevent the electrode assembly 120 from making electrical contact with the lid assembly 140, or to significantly reduce the possibility of such electrical contact. In some examples, the second insulating plate 127 is used to prevent the negative electrode plate 121 in the electrode assembly 120 from making electrical contact with the lid assembly 140, or to significantly reduce the possibility of such electrical contact. Here, when a large amount of gas is generated due to an abnormality of the secondary battery, the first hole 127a is used to allow the gas to quickly move to the lid assembly 140, and the second holes 127b are used to allow the positive electrode tab 125 to pass through it and be welded to the lid assembly 140. In addition, the remaining second holes 127b are used to allow the electrolyte to quickly flow into the electrode assembly 120 during the electrolyte injection process.

[0061] In addition, the diameters of the first holes 126a and 127a of the first and second insulating plates 126 and 127 should be formed to be smaller than the diameter of the center pin 130, so that the center pin 130 does not make electrical contact with the bottom portion 111 of the cylindrical can 110 or the lid assembly 140 when an external impact is applied to it.

[0062] The center pin 130 can have a hollow circular tubular shape and can be coupled to the approximate center of the electrode assembly 120. For example, the center pin 130 can be formed of steel, stainless steel, aluminum, aluminum alloy, polybutylene terephthalate, and / or the like, but is not limited thereto. The center pin 130 is used to suppress the deformation of the electrode assembly 120 during battery charging or discharging and serves as a gas movement channel in the secondary battery. However, the center pin 130 can be omitted in some cases.

[0063] The lid assembly 140 can include a top plate 141, an intermediate plate 142, an insulating plate 143, and a bottom plate 144.

[0064] The intermediate plate 142 may be located below the top plate 141 and may have a substantially flat shape.

[0065] When viewed from below, the insulating plate 143 may form an annular shape having a set or predetermined width. In addition, the insulating plate 143 is used to insulate the intermediate plate 142 and the bottom plate 144 from each other. For example, the insulating plate 143 may be inserted between the intermediate plate 142 and the bottom plate 144 and ultrasonically welded to the intermediate plate 142 and the bottom plate 144, but is not limited thereto.

[0066] Although the present invention has been described by taking a cylindrical secondary battery as an example, the present invention can be applied to any secondary battery including electrodes.

[0067] Figure 3 is a schematic block diagram showing a flow rate control device for coating a multi-partition double layer according to some embodiments of the present invention.

[0068] A flow rate control device 200 for coating a multi-partition double layer (hereinafter referred to as a flow rate control device) can adjust the amount of slurry for coating an electrode in a system for coating an electrode of a secondary battery.

[0069] Referring Figure 3 , the flow rate control device 200 according to some embodiments of the present invention may include a memory 220, a communication unit 230, an input unit 270, an output unit 280, a densitometer 240, a flow meter 250, a valve 260, a pump 290, and a processor 210.

[0070] The densitometer 240 can measure the coating amount (thickness) based on the density of the coated slurry. A separate thickness measuring device can be used as the densitometer 240.

[0071] The densitometer 240 may be installed at each of the front end and the rear end of the drying furnace (for example, installed on each), and may measure the coating amount (for example, its thickness).

[0072] The densitometer 240 can obtain density data or thickness data for the width direction and the moving direction. The densitometer 240 inputs the obtained data into the processor 210.

[0073] The flow meter 250 measures the flow rate of the slurry moved by the pump 290. The flow meter 250 measures the amount of slurry used to coat the electrode and inputs the measured amount into the processor 210.

[0074] The flow meter 250 may be installed at each row corresponding to multiple slit dies (for example, installed on each row). The flow meter 250 may be installed at each of the upper layer and the lower layer of multiple rows (for example, installed on each layer).

[0075] The valve 260 diverts the slurry supplied by the pump 290 and supplies the diverted slurry to the multi-line slot die.

[0076] The valve 260 can adjust the amount of slurry to be supplied. An automatic valve can be used as the valve 260. The valve 260 adjusts the amount of slurry by adjusting its opening degree according to the control command of the processor 210.

[0077] The pump 290 supplies the slurry from the storage tank in which the slurry is accommodated to the system for coating the electrode. One pump 290 can be installed on one storage tank.

[0078] The memory 220 can store the density data or thickness data input from the densitometer 240 and the flow rate data of the slurry input from the flow meter 250. The memory 220 can store the opening degree of the valve 260 and the data of the revolutions per minute (RPM) of the pump 290. In addition, the memory 220 can store the feedback data of the densitometer 240 and store the setting data for controlling the pump 290 and the valve 260 based on the feedback data.

[0079] The memory 220 can store data on flow rate control algorithms, coating amount control algorithms, thickness measurement algorithms, pump control algorithms, interlocking control algorithms, valve control algorithms, etc.

[0080] The memory 220 can include storage media (such as random access memory (RAM), non-volatile memories such as read-only memory (ROM) and electrically erasable programmable ROM (EEPROM)), flash memory, hard disk drive (HDD), solid state drive (SSD), solid state disk drive (SDD), and / or the like.

[0081] The communication unit 230 sends data to and receives data from the processor 210, the memory 220, the densitometer 240, the flow meter 250, the valve 260, the pump 290, the input unit 270, and the output unit 280. In addition, the communication unit 230 can send data to and receive data from an external terminal or server.

[0082] The communication unit 230 supports at least one of near-field communication (such as Ethernet, WiFi, and Bluetooth), mobile communication, and serial communication.

[0083] The input unit 270 can receive data for flow rate control. In addition, the input unit 270 can receive a user command according to the flow rate control. The input unit 270 can include at least one of a button, a switch, and a touchpad.

[0084] The processor 210 can include at least one microprocessor and operate based on the algorithms and data stored in the memory 220.

[0085] The processor 210 controls the pump 290 to supply the slurry for coating the electrodes from the storage tank and adjusts the supply amount of the slurry, and controls the valve 260 to adjust the amount of the slurry supplied to each of the multi-row slit dies.

[0086] The processor 210 supplies the slurry from a storage tank through a pump 290, and the slurry to be supplied is branched and supplied to the multi-row slit die.

[0087] The processor 210 can monitor the amount of the slurry for each row in the multi-rows based on the data measured by the flowmeter 250, and control the valve 260 in response to the monitored amount.

[0088] The processor 210 can control the valve 260 installed at each row in the multi-rows (for example, installed on each row).

[0089] In addition, the processor 210 can measure the flow rate of the slurry controlled by the valve 260 through the flowmeter 250. The processor 210 can measure the flow rates of the slurry for the upper layer and the lower layer of the multi-rows through a plurality of flowmeters 250 installed on the multi-row slit die.

[0090] The processor 210 can receive the flow rate of the slurry for the multi-row slit die measured by the flowmeter 250 and the data of the densitometers 240 connected to the upper end and the lower end of the drying furnace to feedback-control the pump 290 (for example, use the feedback to control the pump 290). In addition, the processor 210 can feedback-control the valve 260 (for example, use the feedback to control the valve 260).

[0091] The processor 210 can adjust the coating amount of the electrodes by continuously feedback-controlling the pump 290 and the valve 260.

[0092] Figure 4 is a diagram showing the configuration of a system for coating a multi-partition double layer according to some embodiments of the present invention.

[0093] Refer to Figure 4 , the system including the flow rate control device 200 may include a storage tank 300, a pump 290, a valve 260, a flowmeter 250, a plurality of slit dies 310, a densitometer 240, and a drying furnace 320.

[0094] The system supplies the slurry accommodated in the storage tank 300 according to the drive of the pump 290 to coat the electrodes of the secondary battery with the slurry.

[0095] In such an example, a double-layer method can be used in the system, in which the upper layer and the lower layer are separated and operated independently. In addition, a system in which multiple rows are formed in the upper part and multiple rows are formed in the lower part in the same or substantially the same manner can be coated on the electrodes by a multi-partition method.

[0096] The flow rate control device 200 can control the pump 290 to supply the slurry from the storage tank 300.

[0097] In such an example, the first pump 291 is included in the upper layer to supply the slurry from the first storage tank 301 in the upper layer to the upper layer. In addition, the second pump 292 in the lower layer supplies the slurry in the second storage tank 302 in the lower layer to the lower layer.

[0098] The processor 210 can control the valves 261, 263, and 265 in the upper layer to supply the same amount of slurry to the rows in the upper layer of the slot die 310 including multiple rows. In addition, the processor 210 can control the valves 262, 264, and 266 in the lower layer to supply the same or substantially the same amount of slurry to the rows in the lower layer of the slot die 310 including multiple rows.

[0099] The processor 210 controls the multiple valves 260 to control the amount of the slurry, and uses the multiple flow meters 251, 253, and 255 to measure the flow rate of the slurry for multiple rows in the upper layer. The processor 210 can use the multiple flow meters 252, 254, and 256 to measure the flow rate of the slurry for multiple rows in the lower layer.

[0100] The processor 210 can feedback-control the control valve 260 based on the measured flow rate for multiple rows. In addition, the processor 210 can calculate the amount of the slurry supplied by the pump 290 based on the sum of the flow rates for multiple rows to control the RPM of the pump 290.

[0101] The processor 210 can control the pump 290 to reduce the amount of the slurry when the total amount of the slurry for each layer is large, and control the pump 290 for the corresponding layer to increase the amount of the slurry when the amount of the slurry is insufficient.

[0102] When there is a difference between the flow rates of the slurry for each row, the processor 210 can control the valve 260 to reduce the difference between the flow rates of the slurry in each row based on the flow rate values for multiple rows. For example, the processor 210 can increase the opening degree of the valve for the row with insufficient flow rate and reduce the opening degree of the valve for the row with high flow rate.

[0103] In addition, when the electrode is coated with the slurry supplied to the multiple slot dies 311 to 313, the processor 210 can use the densitometer 240 to measure the coating thickness and obtain the data for the width direction and the moving direction of the electrode.

[0104] The processor 210 calculates the amount of the slurry for each layer, measures in real time the amount of the slurry for each row in each layer, and controls the pump 290 and the valve 260 to evenly distribute the amount of the slurry to multiple rows.

[0105] The processor 210 can use the flow meters 250 installed at multiple rows to measure the flow rate data of the slurry actually flowing through each row or each layer.

[0106] The processor 210 can input control commands to any layer to adjust the balance of the flow rate of the slurry between the upper layer and the lower layer.

[0107] The processor 210 can obtain the electrode coating amount and deviation for each row based on the data of the flow meter 250 and the data of the densitometer 240. Therefore, it can measure the total load level (hereinafter referred to as L / L) or thickness per unit area to obtain data regarding the width direction and the moving direction.

[0108] Figure 5 FIG. is a diagram showing the operation flow of a flow rate control device for coating a multi-zone double layer according to some embodiments of the present invention.

[0109] According to Figure 5 , the processor 210 can use the pump 290 and the valve 260 to control the flow rate for multiple rows formed on the upper layer A and the lower layer B. Therefore, the processor 210 automatically controls the flow rate of the slurry so that the electrodes are coated with a set or predetermined thickness.

[0110] The processor 210 drives the pumps 290 for the upper layer A and the lower layer B. The processor 210 can drive the first pump 291 (S210) for the upper layer A and the second pump 292 (S215) for the lower layer B.

[0111] The processor 210 can control multiple valves 261, 263, and 265 for the upper layer A (S220), and control multiple valves 262, 264, and 266 for the lower layer B (S225) so that the slurry is distributed and supplied to multiple rows.

[0112] The processor 210 calculates the flow rate for multiple rows of the upper layer A and the lower layer B based on the flow rate data measured by multiple flow meters 250.

[0113] The processor 210 measures the flow rate for multiple rows of the upper layer A using multiple flow meters 251, 253, and 255 (S230). In addition, the processor 210 can measure the flow rate for multiple rows of the lower layer using multiple flow meters 252, 254, and 256 (S235).

[0114] The processor 210 can control the flow rate for each row by controlling the valve 260 based on the flow rate measured by the flow meter 250 (S240). The processor 210 can control the valve according to the flow rate of the upper layer A and the lower layer B to reduce the flow rate difference between each row.

[0115] The processor 210 can compare the average value of all the flow rates for coating in each row with the target flow rate value based on the flow rate of the slurry to control the pump 290 according to the difference between the two.

[0116] In addition, the processor 210 can calculate the total amount of slurry for the upper layer A and the lower layer B based on the data measured by the multiple flow meters 250, and control the pump 290 based on the calculated total amount to control the amount of slurry supplied from the storage tank 300. The processor 210 can adjust the RPM of the pump 290 to adjust the total amount of slurry supplied to the upper layer A and the lower layer B.

[0117] The processor 210 can compare the flow rate of the upper layer A and the flow rate of the lower layer B to control their ratio (S250).

[0118] The processor 210 can compare the flow rate of the upper layer A and the flow rate of the lower layer B to control the pump 290 based on the result.

[0119] In addition, the processor 210 can calculate the dispersion of the coating amount for each row using the flow meter 250 and feedback to the control valve 260.

[0120] The processor 210 can determine the opening degree of the valve 260 installed in each row based on the calculated dispersion to automatically adjust the flow rate of the slurry (S260).

[0121] The processor 210 compares the L / L per unit area and the total thickness measured by the densitometer 240 or the thickness measuring device with the sum of the flow rates of the upper layer A and the lower layer B to compensate for different values.

[0122] The processor 210 can input control commands for the total flow rate of each row to the valves of the upper layer and the valves of the lower layer to control the total flow rate of each row.

[0123] The processor 210 can compensate for the flow rate differences of each layer to eliminate measurement errors.

[0124] Figure 6 is a flowchart showing a flow rate control method for coating a multi-partition double layer according to some embodiments of the present invention.

[0125] Referring to Figure 6 , the processor 210 can use the densitometer 240 to measure the L / L per unit area or the coating thickness.

[0126] The processor 210 can calculate the total average L / L and the total average thickness for multiple rows.

[0127] The processor 210 can calculate the average values for three rows of the upper layer A and three rows of the lower layer B.

[0128] The processor 210 determines whether the L / L and the thickness meet the target values (S320).

[0129] When the L / L and the thickness do not reach the target coating amount, the processor 210 may determine that the amount of the slurry for coating is insufficient and control the RPM of at least one of the pumps 291 and 292 for the upper layer A and the lower layer B (S340).

[0130] In addition, when the L / L and the thickness satisfy the target coating amount, the processor 210 compares the sum of the measured values of the flow meters of the upper layer A with the sum of the measured values of the flow meters of the lower layer B for each slot die to determine whether the ratio thereof satisfies the set value (S330).

[0131] When the ratio between the sum of the flow rates for the upper layer A and the sum of the flow rates for the lower layer B does not satisfy the set value, the processor 210 may control the RPM of at least one of the pumps 291 and 292 for the upper layer A and the lower layer B (S340).

[0132] Therefore, the processor 210 may control the flow rate and the pump 290 in combination with each other.

[0133] When the ratio between the sum of the flow rates for the upper layer A and the sum of the flow rates for the lower layer B satisfies the set value, the processor 210 determines whether the values of the flow meters for each row of the lower layer are the same (S350).

[0134] When the measured values of the flow meters 250 for each row are different, the processor 210 proportionally controls the plurality of valves 260 for the lower layer (S360).

[0135] In addition, the processor 210 may determine whether the L / L and the thickness for each row are the same (S370). When the L / L and the thickness for each row are the same, the processor 210 may proportionally control the valve 260 for the upper layer A (S380).

[0136] The processor 210 may repeatedly perform proportional control on the valve 260 until the conditions are satisfied.

[0137] Therefore, the processor 210 may control the flow rate and the valve 260 in combination with each other.

[0138] In the case where the measured values of the flow meters 250 for each row are the same or substantially the same, or in the case where the L / L and the thickness for each row are the same or substantially the same, the processor 210 may stop the coating control.

[0139] Figure 7 is a table showing the pump control standard values of the flow rate control device for coating a multi-zone double layer according to some embodiments of the present invention.

[0140] According to Figure 7 , the processor 210 may control the flow meter 250 and the pump 290 in combination with each other.

[0141] The processor 210 can measure the amount of slurry supplied to the slot die 310 using the flowmeter 250 and control the pump 290 based on the measured flow rate value according to the associated control algorithm.

[0142] The slurry supplied to the slot die 310 passes through the flowmeter 250, moves in the moving direction, and coats the electrode.

[0143] Therefore, the processor 210 can calculate the coating amount based on the flow rate measured by the flowmeter 250. Thus, the processor 210 can analyze, in combination with each other, the amount of slurry supplied to the slot die 310, the flow rate measured by the flowmeter 250, and the coating amount measured by the densitometer 240.

[0144] The processor 210 can calculate the average flow rate value of the flow rate for each row. When the average flow rate value is less than the target flow rate value, the processor 210 can control the pump 290 to increase the supply amount of the slurry, and when the average flow rate value is greater than the target flow rate value, the processor 210 can control the pump 290 to reduce the supply amount of the slurry.

[0145] In addition, the processor 210 can calculate the average value of the coating amount (such as coating thickness) for each row and calculate the flow rate value to reach the target coating amount to control the pump 290.

[0146] Therefore, as Figure 7 shown, the processor 210 can repeat experiments to standardize the RPM of the pump 290.

[0147] The processor 210 can refer to Figure 7 set the RPM of the pump 290 and repeatedly perform the process of changing the RPM of the pump 290 according to the flow rate value and the thickness to obtain the target flow rate value.

[0148] The processor 210 can store the settings of the pump 290 that satisfy the target flow rate value in the memory 220.

[0149] Therefore, the processor 210 can obtain data on the RPM change amount of the pump based on the change amount calculated by subtracting the target flow rate from the average flow rate in the moving direction.

[0150] The processor 210 can divide the change amount into multiple levels (which can be changed as needed) to set the change amount of the RPM of the corresponding pump. In such an example, since the difference in the change amount of the RPM can vary according to the properties of the slurry used as the coating agent, the optimal corresponding value for each type of slurry can be found through experiments.

[0151] Figure 8 is a table showing the standard values of the opening degrees of the valves of the flow rate control device for coating a multi-partition double layer according to some embodiments of the present invention.

[0152] According to Figure 8 ,the processor 210 can control the valve 260 in combination with the measurement value of the flowmeter 250.

[0153] The processor 210 can group a slot die 310, a flowmeter 250, and a valve 260, and calculate the deviation of the coating amount for each slot die.

[0154] The processor 210 can control the opening degree of the valve based on the calculated deviation according to the deviation range as in Figure 8 .

[0155] In such an example, the opening degree of the control valve 260 can change the flow rate of the slurry for the slot die 310, and the coating amount of the electrode can change according to the change in the flow rate of the slurry.

[0156] The processor 210 can repeatedly adjust the opening degree of the valve according to the deviation to calculate the opening degree of the valve that meets the target coating amount. In such an example, since there are changes in valve adjustment and coating amount according to the type of slurry, the optimal value for each type of slurry can be found.

[0157] Figure 9A and Figure 9B show graphs of the deviation of the flow rate and thickness of the pump operation of the flow rate control device for coating a multi-zone double layer according to some embodiments of the present invention.

[0158] As Figure 9A shown, the processor 210 can calculate the deviation of the coating amount according to the RPM of the pump 290 and the flow rate measured by the flowmeter 250, and analyze the correlation between the RPM of the pump 290 and the flow rate. The relationship between the RPM of the pump 290 and the flow rate can have a linear characteristic (for example, the flow rate can be linearly proportional to the RPM of the pump 290).

[0159] When the RPM of the pump 290 increases, the flow rate increases in response, and the deviation for each RPM of the pump 290 can be calculated.

[0160] In addition, as Figure 9B shown, the measurement deviation of the flow rate according to the RPM of the pump 290 can be checked. This deviation is the difference between the maximum value and the minimum value during multiple (for example, three times) measurements.

[0161] In such an example, the processor 210 can control the flow rate within the actual use range D1 (which is an example of calculating the lowest deviation), and the RPM of the pump 290 is 180 and 210.

[0162] Since the deviation is about ±1%, the processor 210 can control the flow rates of the plurality of slit dies 310 for the upper layer A and the lower layer B.

[0163] Figure 10A and 10B FIG. shows a graph of the flow rate control results of a flow rate control device for coating a multi-zone double layer according to some embodiments of the present invention.

[0164] As Figure 10A and Figure 10B shown, the processor 210 supplies the slurry to the upper layer A and the lower layer B, distributes the slurry into multiple rows, and measures the flow rate of the slurry using the flow meter 250.

[0165] The processor 210 can calculate the deviation of the flow rate in the lower layer B.

[0166] The processor 210 can calculate the deviation in each row of the upper layer A and the lower layer B.

[0167] The processor 210 can verify the flow rate control within a flow rate deviation of ±0.2% in the lower layer B and a flow rate deviation of ±0.5% in the upper layer A and the lower layer B.

[0168] The processor 210 can control the pump 290 and the valve 260 according to the flow rate to reduce the deviation so as to achieve the target coating amount.

[0169] Therefore, the flow rate control device and method for coating a multi-zone double layer according to the present invention can stabilize the process of coating the electrode through a method of coating the multi-zone double layer by the following steps, and can improve the quality by uniformly controlling the coating amount. The steps include: adjusting the amount of the slurry for each row by the valve when adjusting the slurry supply amount by the pump; adjusting the pump and the valve based on the flow rate measured by the flow meter; and calculating the RPM of the pump and the opening degree of the valve corresponding to the target coating amount.

[0170] The present invention described in this specification can be implemented by, for example, a method, a process, a device, a software program, a data stream, or a signal. Even when the present invention is described as being implemented only in a single form (e.g., as a method), the described features can be implemented in another form (e.g., as a device or a program). The device can be implemented using appropriate hardware, software, firmware, or the like. For example, the method can be implemented in a device such as a processor, which generally refers to processor devices such as a computer, a microprocessor, an integrated circuit, and a programmable logic device. The processor includes communication devices such as a computer, a cellular phone, a portable / personal digital assistant (PDA) terminal, and other devices that facilitate information communication between end users.

[0171] In such an example, the processor can be implemented as a CPU, a system-on-chip (SoC), or the like, can drive an operating system or an application program to control a plurality of hardware or software components connected to the processor, and can perform various data processing and operations. The processor can be configured to execute at least one command stored in the memory and store the result data of the execution in the memory.

[0172] According to the present invention, when the electrodes of a secondary battery are coated, a flowmeter capable of measuring the actual flow rate is installed in each slot die through which the slurry is supplied, and the coating amount of each slot die in multiple upper and lower rows is measured to adjust the supply amount of the slurry. Therefore, the coating quality can be easily evaluated, and the coating quality can also be improved (e.g., increased).

[0173] According to the present invention, since the flow rate can be measured to check the coating amount in real time, and a small number of pumps are used to supply the slurry in multiple rows, and feedback control is performed according to the flow rate, the electrode coating process can be stabilized.

[0174] According to the present invention, since the number of storage tanks and pumps for supplying the slurry is reduced to simplify the structure, the above process can be more easily performed, and the manufacturing cost can be reduced.

[0175] It should be understood that the embodiments described herein should be considered in a descriptive sense and not for purposes of limitation. The description of features or aspects within each embodiment should generally be considered available for other similar features or aspects in other embodiments. Although one or more embodiments have been described with reference to the accompanying drawings, those of ordinary skill in the art will understand that various changes in form and detail can be made therein without departing from the spirit and scope defined by the appended claims and their equivalents.

[0176] This application claims the priority and benefits of Korean Patent Application No. 10-2023-0172413, filed with the Korean Intellectual Property Office on December 1, 2023, the disclosure of which is incorporated herein by reference.

Claims

1. A flow rate control device for coating a multi-zone double layer, comprising: a plurality of slot dies, allocated as upper and lower layers and configured to coat the electrode with the slurry; a pump configured to supply the slurry from a storage tank to each of the upper layer and the lower layer; a valve at the plurality of slot dies and configured to divert the slurry supplied from the pump and supply the diverted slurry to the plurality of slot dies; a flow meter configured to measure a flow rate of the slurry supplied to the plurality of slot dies; as well as A processor is configured to control the pump and the valve based on the flow rate of the slurry measured by the flow meter to control the coating amount of the electrode.

2. The flow rate control device according to claim 1, wherein: The valve is provided as a plurality of valves; the slurry to be supplied to the upper layer is supplied to the plurality of slot dies of the upper layer by the pump; as well as The slurry to be supplied to the lower layer is supplied to the plurality of slot dies of the lower layer by the pump.

3. The flow control device according to claim 1, wherein the pump comprises: a first pump configured to supply the slurry contained in the storage tank to the upper layer; as well as A second pump is configured to supply the slurry contained in the storage tank to the lower layer.

4. The flow rate control device according to claim 1, wherein: The processor is configured to receive the flow rate for each of the plurality of slot dies using the flow meter and compare a sum of the flow rates for the upper layer with a sum of the flow rates for the lower layer; as well as In response to the ratio between the sum of the flow rates for the upper layer and the sum of the flow rates for the lower layer not reaching a target value, the processor is configured to control the revolutions per minute (RPM) of the pump to adjust the supply amount of the slurry supplied to either the upper layer or the lower layer.

5. The flow rate control device according to claim 1, wherein: The processor is configured to compare flow rates for the plurality of slot dies in the lower layer; as well as In response to a flow rate difference for the plurality of slot dies existing between rows, the processor is configured to control the valve to reduce the flow rate difference of the slurry for the plurality of slot dies. 6 . The flow rate control device according to claim 1 , further comprising a densitometer configured to measure a thickness of a coating amount of the electrode.

7. The flow rate control device according to claim 6, wherein: In response to the coating amount of the electrode measured by the densitometer not satisfying a target coating amount, the processor is configured to control the pump to adjust a supply amount of the slurry.

8. The flow rate control device according to claim 6, wherein: The processor is configured to calculate a difference between rows in coating amounts for the plurality of slot dies measured using the densitometer; as well as In response to the coating amount difference for the plurality of slot dies existing between the rows, the processor is configured to control the valve to adjust a flow rate of the slurry supplied to the plurality of slot dies.

9. The flow rate control device according to claim 1, wherein the processor is configured to calculate an average value of the flow rates of the plurality of slit dies in a row measured by the flow meter, calculate a variation by subtracting a target flow rate from the average value of the flow rates, and set the variation of the revolutions per minute (RPM) of the pump according to a range of the variation.

10. The flow rate control device according to claim 1, wherein the processor is configured to calculate a grand average of the flow rates measured by the flow meter, calculate a deviation using a value obtained by subtracting the flow rate of a row from the grand average, and adjust the opening of the valve according to the size of the deviation.

11. A flow rate control method for coating a multi-zone double layer, comprising: supplying a slurry for coating an electrode from a storage tank to a plurality of slot dies at upper and lower layers by a pump; diverting the slurry supplied from the pump through a valve, and supplying the diverted slurry to the plurality of slot dies at the upper layer and the lower layer; measuring a flow rate of the slurry supplied to the plurality of slot dies by a flow meter; as well as The flow rate of the slurry supplied to any one of the plurality of slot dies is changed by a processor by controlling at least any one of the pump and the valve based on the flow rate of the slurry measured by the flow meter.

12. The flow rate control method according to claim 11, wherein the supplying of the slurry comprises: supplying the slurry contained in the storage tank to the upper layer by a first pump; as well as The slurry contained in the storage tank is supplied to the lower layer by a second pump.

13. The flow rate control method according to claim 11, wherein the diversion of the slurry and the supply of the diverted slurry comprise: diverting the slurry to be supplied to the upper layer through a valve installed at the upper layer, and supplying the diverted slurry to the plurality of slot dies provided in the upper layer; as well as The slurry to be supplied to the lower layer is branched by a valve installed at the lower layer, and the branched slurry is supplied to the plurality of slot dies provided in the lower layer.

14. The flow rate control method according to claim 11, wherein the change of the flow rate of the slurry comprises: receiving, by the flow meter, each of the flow rates for the plurality of slot dies, and comparing a sum of the flow rates for the upper layer with a sum of the flow rates for the lower layer; determining whether a ratio between the sum of the flow rates for the upper layer and the sum of the flow rates for the lower layer reaches a target value based on the comparison result; and In response to the ratio between the sum of the flow rates for the upper layer and the sum of the flow rates for the lower layer not reaching the target value, the revolutions per minute (RPM) of the pump is controlled to adjust the supply amount of the slurry supplied to either the upper layer or the lower layer.

15. The flow rate control method according to claim 11, wherein the change of the flow rate of the slurry comprises: comparing the flow rates for the plurality of slot dies at the lower layer; as well as In response to a flow rate difference existing between rows of the plurality of slot dies, the valve is controlled to reduce the flow rate difference of the slurry to the plurality of slot dies.

16. The flow rate control method of claim 11, wherein the change in the flow rate of the slurry comprises: calculating an average of the flow rates measured by the flow meter for the plurality of slot dies in a row; calculating the variation by subtracting the target flow rate from the average value of the flow rates; and According to the range of the change amount, the change amount of the revolutions per minute (RPM) of the pump is set.

17. The flow rate control method of claim 11, wherein the changing of the flow rate of the slurry comprises: calculating a grand average of the flow rate measured by the flow meter; calculating a dispersion using a value calculated by subtracting the flow rate for the row from the overall average; as well as The opening of the valve is adjusted according to the size of the deviation.

18. The flow rate control method according to claim 11, further comprising measuring a thickness of the coating amount for the electrode by a densitometer.

19. The flow rate control method according to claim 18, further comprising: comparing, by the processor, the coating amount for the electrode measured by the densitometer with a target coating amount; as well as In response to the coating amount of the electrode not satisfying the target coating amount, the supply amount of the slurry is adjusted by controlling the pump through the processor.

20. The flow rate control method according to claim 18, further comprising: calculating, by the processor, differences in coating amounts for the plurality of slot dies measured by the densitometer between rows; as well as In response to the difference in the coating amount for the plurality of slot dies existing between the rows, the flow rate of the slurry supplied to the plurality of slot dies is adjusted by controlling the valve by the processor.

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