Electrode manufacturing device and electrode manufacturing method

Abstract

The present invention relates to an electrode manufacturing device and an electrode manufacturing method wherein, when restarting a coating unit after stopping same, the rotational speed of a fan inside a drying unit can be adjusted, to a speed lower than the speed before the coating unit was stopped, on the basis of the internal humidity of the drying unit to effectively prevent over-drying.

Description

Electrode manufacturing device and electrode manufacturing method

[0001] The present invention relates to an electrode manufacturing device and an electrode manufacturing method.

[0002] This application claims the benefit of priority to Korean Patent Application No. 10-2024-0066354, filed May 22, 2024, the entire contents of which are incorporated herein by reference.

[0003] Lithium secondary batteries have electrodes containing active materials exhibiting electrical activity. These electrodes are manufactured by coating electrode slurry containing the active material on an electrode sheet to form a composite layer, and drying the same. For the manufacturing process of such electrodes, a coating device for coating electrode slurry on an electrode sheet that is transported in one direction during electrode manufacturing and a drying device for drying the electrode sheet coated with electrode slurry to volatilize (or remove) the solvent within the electrode slurry have been conventionally used.

[0004] Typically, drying devices have primarily been drying ovens equipped with fans that supply hot air. In drying ovens, the amount of hot air supplied can be controlled by adjusting the fan rotation speed. Depending on the amount of hot air supplied, the amount of solvent vaporized within the slurry is determined, enabling the production of a final product with a desired drying rate.

[0005] Even if the amount of hot air supplied to the drying device remains constant, the drying rate of the final product can vary depending on the internal humidity of the drying device. Accordingly, for existing drying devices, drying conditions (e.g., fan rotation speed) were established within a range where the internal humidity of the drying device converged to a constant level during normal coating and drying processes.

[0006] Meanwhile, due to various unavoidable circumstances, the operation of the coating device was often halted for a certain period of time. Since the slurry coating did not occur during the downtime of the coating device, the longer the downtime, the less the solvent within the slurry volatilized within the drying device. Consequently, the internal humidity of the drying device during the downtime became relatively lower than the internal humidity of the drying device prior to the coating device being stopped.

[0007] In this way, when restarting the coating device in a situation where the internal humidity of the drying device is relatively low, there was a problem of over-drying of the electrode when the drying conditions of the drying device established in a situation where the internal humidity is relatively high were applied.

[0008] The present invention aims to provide an electrode manufacturing device and an electrode manufacturing method that can effectively prevent over-drying when restarting a coating part after stopping it.

[0009] In addition, the present invention aims to provide an electrode manufacturing device and an electrode manufacturing method capable of preventing overdrying by controlling the speed of a fan inside a drying section to a lower rotation speed than the rotation speed before stopping based on the measured internal humidity of the drying section when restarting the coating section after stopping.

[0010] In order to solve the above problem, according to one embodiment of the present invention, a method for manufacturing an electrode is provided, including a coating step of coating an electrode slurry on an electrode sheet being transported in one direction from a coating section, a drying step of operating a fan supplying hot air in a drying section at a first rotation speed set in advance and drying the electrode slurry coated on the electrode sheet through the hot air, and a control step of controlling the operation of the coating section and the drying section, and controlling the rotation speed of the fan in the drying section to a second rotation speed lower than the first rotation speed based on the measured internal humidity of the drying section when the coating section is restarted after being stopped.

[0011] In addition, in the electrode manufacturing method, when the measured internal humidity of the drying section is a second internal humidity lower than the first internal humidity before stopping or a third internal humidity lower than the second internal humidity when the coating section is restarted after stopping, in the control step, the rotation speed of the fan in the drying section can be controlled to a second rotation speed at the second internal humidity, and to a third rotation speed lower than the second rotation speed at the third internal humidity.

[0012] In addition, in the above electrode manufacturing method, the drying unit includes a plurality of drying chambers through which the electrode sheets pass in sequence, and in the control step, the rotation speed of the fan in each drying chamber can be controlled to the same rotation speed.

[0013] In addition, in the above electrode manufacturing method, the drying unit additionally includes a heater, and in the control step, the operating conditions of the heater before stopping the coating unit and the operating conditions of the heater when restarting can be controlled to be the same.

[0014] In addition, the electrode manufacturing method may include a setting step of dividing the internal humidity of the drying section into a plurality of sections and setting the optimal rotation speed for each section.

[0015] In addition, in the above electrode manufacturing method, when the coating part is restarted after being stopped, a measurement step of measuring the internal humidity of the drying part is included, and the control step can search for a section corresponding to the measured internal humidity of the drying part and control the rotation speed of the fan in the drying part at the set rotation speed of the searched section.

[0016] In addition, the electrode manufacturing method may include a collection step of collecting information on the weight of the electrode sheet coated with the electrode slurry before drying, the weight of the electrode sheet coated with the electrode slurry after drying, and the solid content of the electrode slurry coated on the electrode sheet before drying; and an evaluation step of evaluating whether the first rotation speed is appropriate based on the collected information.

[0017] In addition, in the above electrode manufacturing method, the evaluation step can evaluate the first rotation speed as appropriate when the dry rate of the electrode calculated according to the following equations 1 and 2 is within the range of 80 to 99%:

[0018] [Formula 1]

[0019]

[0020] [Formula 2]

[0021]

[0022] In the above formulas 1 and 2, M1 is the weight of the electrode sheet coated with the electrode slurry before drying, M1* is the average weight of the electrode sheet coated with the electrode slurry before drying, M2 is the weight of the electrode sheet coated with the electrode slurry after drying, M2* is the weight of the electrode sheet coated with the overdried electrode slurry after drying, and M3 is the solid content of the electrode slurry coated on the electrode sheet before drying.

[0023] According to another embodiment of the present invention, an electrode manufacturing device is provided, including a coating unit for coating electrode slurry on an electrode sheet transported in one direction, a drying unit for operating a fan for supplying hot air at a preset first rotation speed and for drying the electrode slurry coated on the electrode sheet through the hot air, and a control unit for controlling the operation of the coating unit and the drying unit, and for controlling the rotation speed of the fan in the drying unit to a second rotation speed lower than the first rotation speed based on the measured internal humidity of the drying unit when the coating unit is restarted after being stopped.

[0024] In addition, in the electrode manufacturing device, when the coating section is restarted after being stopped, when the measured internal humidity of the drying section is a second internal humidity lower than the first internal humidity before stopping or a third internal humidity lower than the second internal humidity, the control section can control the rotation speed of the fan inside the drying section to a second rotation speed at the second internal humidity, and can control the rotation speed of the fan inside the drying section to a third rotation speed lower than the second rotation speed at the third internal humidity.

[0025] Additionally, in the electrode manufacturing device, the drying unit includes a plurality of drying chambers through which the electrode sheets pass in sequence, and the control unit can control the rotation speed of the fan in each drying chamber to the same rotation speed.

[0026] In addition, in the electrode manufacturing device, the drying unit additionally includes a heater, and the control unit can control the operating conditions of the heater before stopping the coating unit and the operating conditions of the heater when restarting to be the same.

[0027] In addition, the electrode manufacturing device may include a setting unit that divides the internal humidity of the drying section into a plurality of sections and sets the optimal rotation speed for each section.

[0028] In addition, in the electrode manufacturing device, when the coating part is restarted after being stopped, a measuring part is included to measure the internal humidity of the drying part, and the control part can search for a section corresponding to the measured internal humidity of the drying part and control the rotation speed of the fan in the drying part at the set rotation speed of the searched section.

[0029] In addition, the electrode manufacturing device may include a collection unit that collects information on the weight of the electrode sheet coated with the electrode slurry before drying, the weight of the electrode sheet coated with the electrode slurry after drying, and the solid content of the electrode slurry coated on the electrode sheet before drying; and an evaluation unit that evaluates whether the first rotation speed is appropriate based on the collected information.

[0030] In addition, in the electrode manufacturing device, the evaluation unit can evaluate the first rotation speed as appropriate when the dry rate of the electrode calculated according to the following equations 1 and 2 is within the range of 80 to 99%:

[0031] [Formula 1]

[0032]

[0033] [Formula 2]

[0034]

[0035] In the above formulas 1 and 2, M1 is the weight of the electrode sheet coated with the electrode slurry before drying, M1* is the average weight of the electrode sheet coated with the electrode slurry before drying, M2 is the weight of the electrode sheet coated with the electrode slurry after drying, M2* is the weight of the electrode sheet coated with the overdried electrode slurry after drying, and M3 is the solid content of the electrode slurry coated on the electrode sheet before drying.

[0036] As described above, the electrode manufacturing device and electrode manufacturing method related to one embodiment of the present invention have the following effects.

[0037] When restarting the coating section after stopping, overdrying can be effectively prevented by adjusting the speed of the fan inside the drying section to a lower rotation speed than the rotation speed before stopping based on the measured internal humidity of the drying section.

[0038] Figure 1 is a block diagram of an electrode manufacturing device according to one embodiment of the present invention.

[0039] Figure 2 is a detailed configuration diagram of an electrode manufacturing device according to one embodiment of the present invention.

[0040] Figures 3 to 6 are drawings for explaining the stop and restart states of the coating section and drying section of the electrode manufacturing device according to one embodiment of the present invention.

[0041] Hereinafter, an electrode manufacturing device and an electrode manufacturing method according to one embodiment of the present invention will be described in detail with reference to the attached drawings.

[0042] In addition, regardless of the drawing symbol, identical or corresponding components are given identical or similar reference numbers and redundant descriptions thereof are omitted, and for the convenience of explanation, the size and shape of each component depicted may be exaggerated or reduced.

[0043] FIG. 1 is a block diagram of an electrode manufacturing device according to one embodiment of the present invention, and FIG. 2 is a detailed diagram of an electrode manufacturing device according to one embodiment of the present invention.

[0044] Referring to FIGS. 1 and 2, the electrode manufacturing device (1) includes a coating unit (100), a drying unit (200), and a control unit (300).

[0045] The coating unit (100) is provided to coat electrode slurry (20) on an electrode sheet (10) being transported. Specifically, the coating unit (100) coats electrode slurry (20) on an electrode sheet (10) being transported in one direction. In addition, the coating unit (100) may include one or more coaters (e.g., a slot die coater) and may be provided to coat (or apply) electrode slurry (20) on one or both sides of the electrode sheet (10).

[0046] The electrode sheet (10) may be a negative electrode or a positive electrode sheet. The electrode slurry (20) may include an electrode active material and a solvent, and may further include additives such as a conductive material and a binder. For example, when the electrode sheet (10) is a negative electrode sheet, the electrode slurry (20) may include a negative electrode active material, and when the electrode sheet (10) is a positive electrode sheet, the electrode slurry (20) may include a positive electrode active material. The detailed composition of the active material is not particularly limited, and various known compositions may be used without limitation.

[0047] The electrode manufacturing device according to the present invention may include a conveying unit (400) that conveys an electrode sheet (10) in one direction. The conveying unit (400) may be any equipment capable of conveying an electrode sheet, and may use a conveyor belt, conveying roller, or the like, without particular limitations. For example, the conveying unit (400) may be configured to convey the electrode sheet in a roll-to-roll manner via a plurality of conveying rollers. The electrode sheet (10) may have a predetermined length and may be sequentially conveyed to the drying unit (200) via the coating unit (100) while being seated on the conveying unit (400).

[0048] The drying unit (200) is provided to dry the electrode slurry (20) coated on the electrode sheet (10). The drying unit (200) may include a fan (210) capable of controlling the rotation speed (rpm) and a humidity sensor (230). The drying unit (200) operates the fan (210) supplying hot air at a preset first rotation speed, and dries the electrode slurry (20) coated on the electrode sheet (10) through the hot air. The drying degree of the electrode may be determined according to the rotation speed of the fan (210). As the rotation speed of the fan (210) increases, the drying rate of the electrode may increase.

[0049] The term "preset first rotation speed" as mentioned above may be a rotation speed for satisfying a desired drying rate when the internal humidity of the drying unit (200) converges to a constant value or within a constant range in a state in which the coating unit (100) continuously operates for a predetermined period of time without stopping (hereinafter also referred to as a "normal operating state"). That is, by setting the rotation speed of the fan to the first rotation speed, drying conditions within the drying device can be established in the normal operating state.

[0050] For example, the first rotation speed can be determined by considering the drying rate of the desired final product in a section where the internal humidity of the drying unit (200) converges (or is maintained) at a constant level.

[0051] More specifically, when the rotation speed for setting the target drying rate to 80% in a section where the internal humidity of the drying unit (200) converges to a constant level is A (rpm), the rotation speed for setting the target drying rate to 80% or more may be set higher than A (rpm), and the rotation speed for setting the target drying rate to 80% or less may be set lower than A (rpm).

[0052] When the above coating unit (100) and drying unit (200) are operating normally, when the fan (210) operates at the first rotation speed, a final product (dried electrode sheet) having a desired drying rate can be obtained.

[0053] Meanwhile, when the coating unit (100) is restarted after being stopped, the internal humidity of the drying unit (200) may vary depending on the humidity of the hot air or the coating amount (or coating length) of the electrode sheet before stopping. The hot air is heated external air, and the humidity of the hot air may vary depending on the humidity of the external air.

[0054] In addition, the coating length indicates the length along which the electrode slurry (20) is coated on the electrode sheet (10) along the transport direction. The coating length is related to the solvent volatile amount of the electrode slurry (20), and the longer the coating length over which coating is performed before stopping, the greater the amount of electrode slurry (20), and thus the greater the solvent volatile amount. If the solvent volatile amount increases, the internal humidity of the drying section (200) may be relatively high.

[0055] For example, even if the coating unit (100) is stopped, the transport of the electrode sheet (10) by the transport unit (400) can be maintained. Accordingly, while the coating unit (100) is stopped, the electrode sheet (10) that is no longer coated with the electrode slurry (20) can be transported to the drying unit (200).

[0056] During the stop time of the coating section (100), the electrode sheet (10) moves to the drying section (200) without being coated, so that the amount of solvent volatilization within the drying section (200) no longer increases, and the internal humidity of the drying section (200) tends to gradually decrease.

[0057] However, the degree to which the internal humidity of the drying section (200) decreases may vary depending on the coating amount immediately before the coating section (100) is stopped. For example, the greater the coating amount immediately before the coating section (100) is stopped, the less the internal humidity of the drying section (200) decreases during the stop of the coating section (100). In addition, the less the coating amount immediately before the coating section (100) is stopped, the faster the internal humidity of the drying section (200) decreases during the stop of the coating section (100). This is because the greater the coating amount, the greater the amount of solvent volatilization.

[0058] Through the drawing, the change in internal humidity of the drying section (200) according to the coating amount (or coating length) of the electrode slurry (20) will be described in detail.

[0059] Figures 3 and 6 are drawings for explaining the stop and restart states of the coating section and drying section of the electrode manufacturing device according to one embodiment of the present invention.

[0060] Figures 3 to 6 illustrate a drying unit (200) having five drying chambers (201, 202, 203, 204, 205), each having the same stopping time in a state of different coating lengths and a state of restarting.

[0061] FIG. 3 is a drawing showing a state in which the coating length (length in the direction of transfer of the electrode sheet) has advanced by L1 before the coating section (100) is stopped, and FIG. 4 is a drawing showing a state in which the electrode sheet passes through the drying section (200) through the transfer section while the coating section (100) is stopped for a predetermined time in the state shown in FIG. 3.

[0062] In addition, FIG. 5 is a drawing showing a state in which the coating length has progressed by L2 before the coating section (100) is stopped, and FIG. 6 is a drawing showing a state in which the electrode sheet passes through the drying section (200) through the transfer section in a state in which the electrode sheet has been stopped for a predetermined time in the state shown in FIG. 5.

[0063] The stopping times of the coating sections of FIGS. 3 to 6 are the same, and the coating length L1 shown in FIG. 3 is shown to be longer than the coating length L2 shown in FIG. 5. In addition, the longer the coating length coated on the electrode sheet (10) before stopping the coating section (100), the greater the coating amount, and the greater the coating amount, the greater the amount of volatile solvent in the slurry in the drying section (200).

[0064] Referring to FIGS. 4 and 6, the electrode sheet (10) can be continuously moved while the electrode slurry (20) is not coated during the stop time of the coating unit (100). The length of the electrode sheet (10) that is not coated with the electrode slurry (20) and moves to the drying unit (200) during the stop time of the coating unit (100) can be as long as L3. As the stop time of the coating unit (100) becomes longer, the length of the electrode sheet (10) that is not coated with the electrode slurry (20) and moves to the drying unit (200) can become longer.

[0065] Since the stopping time of the coating portion (100) illustrated in FIGS. 3 to 6 is the same, in FIGS. 3 to 6, the length of the electrode sheet (10) not coated with the electrode slurry (20) is illustrated as L3.

[0066] Referring to FIGS. 3 to 6, even if the electrode manufacturing device has the same stopping time, the coating length by the coating unit (100) immediately before the stopping of the coating unit (100) may be different from each other. When the coating length by the coating unit (100) is different from each other, the internal humidity of the drying unit (200) may be different even if the stopping time of the coating unit (100) is the same. For example, the internal humidity of the drying unit (200) illustrated in FIG. 4, which has a relatively long coating length, may be higher than the internal humidity of the drying unit (200) illustrated in FIG. 6.

[0067] As above, since the coating length can affect the internal humidity of the drying section (200), it is desirable to consider the coating length before stopping to prevent overcharging of the electrode.

[0068] The above control unit (300) is provided to control the operation of the coating unit (100) and the drying unit (200). When the coating unit (100) is stopped and then restarted, the control unit (300) controls the rotation speed of the fan (210) inside the drying unit (200) to a second rotation speed lower than the first rotation speed based on the internal humidity of the drying unit (200) measured by the humidity sensor. In the present invention, the internal humidity is absolute humidity (g / m 3 ) may be. In addition, the control unit (300) may additionally control the operation of the transfer unit (400). The control unit (300) may stop the operation of the transfer unit (400) when the stop time of the coating unit (100) continues for a certain period of time or longer.

[0069] As mentioned above, since the first rotation speed is established in a section where the internal humidity of the drying section (200) converges to a constant level when the coating section (100) is operating normally, if the coating section (100) is stopped and then restarted and the internal humidity of the drying section (200) is relatively low and the first rotation speed is maintained, over-drying of the electrode may occur.

[0070] The present invention has the advantage of always being able to prevent over-drying of the electrode regardless of the humidity of the hot air or the coating amount, because the speed of the fan (210) of the drying unit (200) is controlled to a second rotation speed lower than the first rotation speed based on the internal humidity of the drying unit (200) at the time when the coating unit (100) is restarted.

[0071] In one example, when the coating unit (100) is restarted after being stopped, when the measured internal humidity of the drying unit (200) is a second internal humidity lower than the first internal humidity before being stopped or a third internal humidity lower than the second internal humidity, the control unit (300) may control the rotation speed of the fan (210) within the drying unit (200) to a second rotation speed at the second internal humidity, and may control the rotation speed of the fan within the drying unit (200) to a third rotation speed lower than the second rotation speed at the third internal humidity. As described above, the control unit (300) may control the rotation speed of the fan to be lower when the internal humidity of the drying unit (200) is lower when the coating unit (100) is restarted after being stopped, thereby preventing over-drying of the electrode.

[0072] In one specific example, the drying unit (200) includes a plurality of drying chambers (201, 202, 203, 204, 쪋, 200n) through which the electrode sheets pass in sequence, and the control unit (300) can control the rotation speed of the fan (210) in each drying chamber to the same rotation speed. For example, the number of the plurality of drying chambers (201, 202, 203, 204, 쪋, 200n) may be 10 or more, but is not limited thereto. The plurality of drying chambers (201, 202, 203, 204, 쪋, 200n) may be spaced apart from each other along the transport direction of the electrode sheets (10). For example, an electrode sheet (10) coated with electrode slurry (20) begins to dry when it passes through the first drying chamber (201), and can achieve the final target drying rate when it passes through the last drying chamber (200n).

[0073] In another example, the drying unit (200) may additionally include a heater (220) for heating the electrode sheet (10). For example, each drying chamber may include a fan and a heater. The control unit (300) may control the operating conditions of the heater (220) before the coating unit (100) is stopped and the operating conditions of the heater (220) when it is restarted to be the same. For example, the control unit (300) may control the operating conditions of the heaters of each drying chamber to be the same. The drying unit (200) may control the drying rate of the electrode sheet (10) by controlling the rotation speed of the fan (210) or the temperature (or output) of the heater (200). However, controlling the rotation speed of the fan (210) may be reflected relatively quickly in the drying degree of the electrode compared to controlling the temperature of the heater (220).

[0074] The electrode manufacturing device according to the present invention can exhibit high responsiveness to the electrode drying rate by controlling only the rotation speed of the fan (210) differently while controlling the operating conditions of the heater (220) identically before and after stopping the coating section (100).

[0075] In one example, the drying unit (200) may include a setting unit that divides the internal humidity measured into multiple sections and sets the optimal rotation speed for each section.

[0076] The optimal rotation speed set in the above setting section may be a rotation speed that enables production of a final product that satisfies the target drying rate without causing overdrying of the electrode.

[0077] For example, the above setting unit is configured so that the internal humidity of the drying unit (200) is 7.5 g / m 3 The first section below, the internal humidity of the drying section (200) is 7.5 to 15 g / m 3 In the second section, the internal humidity of the drying section (200) is 15 g / m 3The above is divided into three sections, and the optimal rotation speed can be set in the first to third sections. Since the internal humidity increases as one moves from the first section to the second section to the third section, the rotation speed set can increase as one moves from the first section to the second section to the third section.

[0078] In one specific example, the drying unit (200) includes a measuring unit that measures the internal humidity of the drying unit (200) when the coating unit (100) is restarted after being stopped, and the control unit (300) can search for a section corresponding to the measured internal humidity of the drying unit (200) and control the rotation speed of the fan (210) in the drying unit (200) at the set rotation speed of the searched section. The measuring unit may be a humidity sensor. For example, when the internal humidity of the drying unit (200) measured when the coating unit (100) is restarted after being stopped is 10 g / m 3 In this case, the control unit (300) can control the rotation speed of the fan (210) in the drying unit (200) at the rotation speed set in the second section described above.

[0079] In one example, an electrode manufacturing device according to the present invention may include a collection unit (400) that collects information on the weight of an electrode sheet (10) coated with electrode slurry (20) before drying, the weight of an electrode sheet (10) coated with electrode slurry (20) after drying, and the solid content of the electrode slurry (20) coated on the electrode sheet (10) before drying, and an evaluation unit (500) that evaluates whether the first rotation speed is appropriate based on the collected information. The weight may be measured using a web-gauge.

[0080] Here, the electrode sheet (10) coated with the electrode slurry (20) after drying may be heavier the less dried it is, and lighter the more overdried it is. This is because the less dried it is, the more solvent remains in the electrode slurry (20) without being evaporated.

[0081] Specifically, the evaluation unit (500) can evaluate the first rotation speed as appropriate when the dry rate of the electrode (E) calculated according to the following equations 1 and 2 is within the range of 80 to 99%. The dry rate may be, for example, 81 to 98%, 81 to 97%, 81 to 96%, 81 to 95%, 81 to 94%, 81 to 93%, 81 to 92%, 82 to 98%, 82 to 97%, 82 to 96%, 82 to 95%, 82 to 94%, 82 to 93%, or 82 to 92%. The above drying rate may vary depending on the product specifications within the above range, and satisfying the above drying rate at the first and second rotation speeds may mean that the internal humidity of the drying unit (200) is effectively reflected, and there is no problem with drying the electrode, such as over-drying or under-drying of the electrode.

[0082] [Formula 1]

[0083]

[0084] [Formula 2]

[0085]

[0086] In the above formulas 1 and 2, M1 is the weight of the electrode sheet (10) coated with the electrode slurry (20) before drying, M1* is the average weight of the electrode sheets (10) coated with the electrode slurry (20) before drying, M2 is the weight of the electrode sheet (10) coated with the electrode slurry (20) after drying, M2* is the weight of the electrode sheet (10) coated with the overdried electrode slurry (20) after drying, and M3 is the solid content of the electrode slurry (20) coated on the electrode sheet (10) before drying. More specifically, when there are multiple electrode sheets (10) coated with the electrode slurry (20) before drying, M1* can be calculated through the average value of these.

[0087] Meanwhile, in the past, the weight of the electrode sheet (10) coated with electrode slurry (20) after drying was measured using a web gauge, and the drying rate was evaluated as not dried, normally dried, or overdried. For example, in the existing method, the more the weight of the electrode sheet (10) coated with electrode slurry (20) after drying was, the more solvent it contained, and thus it was evaluated as not dried. However, this existing method had an error in that it was unclear whether the not dried electrode was insufficiently dried or whether the weight of the electrode sheet (10) coated with electrode slurry (20) before drying was heavy.

[0088] In contrast, since the evaluation unit (500) according to the present invention determines the drying rate by considering the weight of the solid content before and after drying as described above, errors occurring in the existing measurement method can be prevented, and thus the reliability of the evaluation can be excellent.

[0089]

[0090] The present invention also relates to a method for manufacturing an electrode. This method is a method for manufacturing an electrode using the aforementioned electrode manufacturing device. Therefore, a detailed description that overlaps with the above will be omitted below.

[0091] Specifically, the electrode manufacturing method includes a coating step of coating electrode slurry (20) on an electrode sheet (10) that is transported in one direction from a coating section (100), a drying step of operating a fan that supplies hot air in a drying section (200) at a preset first rotation speed and drying the electrode slurry (20) coated on the electrode sheet (10) through the hot air, and a control step of controlling the operation of the coating section (100) and the drying section (200), and when the coating section (100) is stopped and then restarted, controlling the rotation speed of the fan (210) in the drying section (200) to a second rotation speed lower than the first rotation speed based on the measured internal humidity of the drying section (200).

[0092] In one example, when the coating unit (100) is restarted after being stopped, when the measured internal humidity of the drying unit (200) is a second internal humidity lower than the first internal humidity before stopping or a third internal humidity lower than the second internal humidity, in the control step, the rotation speed of the fan in the drying unit can be controlled to a second rotation speed at the second internal humidity, and to a third rotation speed lower than the second rotation speed at the third internal humidity.

[0093] In addition, the drying unit (200) includes a plurality of drying chambers (201, 202, 203, 204, 쪋, 200n) through which the electrode sheets pass in sequence, and in the control step, the rotation speed of the fan (210) in each drying chamber can be controlled to the same rotation speed.

[0094] In another example, the drying unit (200) additionally includes a heater (220), and in the control step, the operating conditions of the heater (220) before stopping the coating unit (100) and the operating conditions of the heater (220) when restarting can be controlled to be the same.

[0095] For example, it may include a setting step of dividing the internal humidity of the drying unit (200) into multiple sections and setting the optimal rotation speed for each section.

[0096] In addition, the electrode manufacturing method according to the present invention includes a measurement step of measuring the internal humidity of the drying section (200) when the coating section (100) is restarted after being stopped, and the control step can search for a section corresponding to the measured internal humidity of the drying section (200) and control the rotation speed of the fan (210) in the drying section (200) at the set rotation speed of the searched section.

[0097] In addition, the electrode manufacturing method according to the present application may include a collection step of collecting information on the weight of the electrode sheet (10) coated with the electrode slurry (20) before drying, the weight of the electrode sheet (10) coated with the electrode slurry (20) after drying, and the solid content of the electrode slurry (20) coated on the electrode sheet (10) before drying, and an evaluation step of evaluating whether the first rotation speed is appropriate based on the collected information.

[0098] In one specific example, the evaluation step may evaluate the first rotation speed as appropriate when the dry rate of the electrode calculated according to the following equations 1 and 2 is within the range of 80 to 99%.

[0099] [Formula 1]

[0100]

[0101] [Formula 2]

[0102]

[0103]

[0104] In the above formulas 1 and 2, M1 is the weight of the electrode sheet (10) coated with the electrode slurry (20) before drying, M1* is the average weight of the electrode sheet (10) coated with the electrode slurry (20) before drying, M2 is the weight of the electrode sheet (10) coated with the electrode slurry (20) after drying, M2* is the weight of the electrode sheet (10) coated with the overdried electrode slurry (20) after drying, and M3 is the solid content of the electrode slurry (20) coated on the electrode sheet (10) before drying.

[0105] The preferred embodiments of the present invention described above are disclosed for the purpose of illustration, and those skilled in the art having ordinary knowledge of the present invention will be able to make various modifications, changes, and additions within the spirit and scope of the present invention, and such modifications, changes, and additions should be considered to fall within the scope of the following claims.

[0106] According to an electrode manufacturing device and an electrode manufacturing method related to one embodiment of the present invention, overdrying can be effectively prevented when the coating part is restarted after being stopped.

Claims

1. A coating step of coating electrode slurry on an electrode sheet transported in one direction from a coating section; A drying step in which a fan supplying hot air into a drying section is operated at a preset first rotation speed and the electrode slurry coated on the electrode sheet is dried through the hot air; and An electrode manufacturing method comprising a control step of controlling the operation of a coating unit and a drying unit, and controlling the rotation speed of a fan in the drying unit to a second rotation speed lower than the first rotation speed based on the measured internal humidity of the drying unit when the coating unit is restarted after being stopped.

2. In the first paragraph, when the coating part is restarted after being stopped, when the measured internal humidity of the drying part is a second internal humidity lower than the first internal humidity before stopping or a third internal humidity lower than the second internal humidity, The above control step is a method for manufacturing an electrode, wherein the rotation speed of the fan in the drying section is controlled to a second rotation speed at a second internal humidity, and to a third rotation speed lower than the second rotation speed at a third internal humidity.

3. In the first paragraph, the drying unit includes a plurality of drying chambers through which the electrode sheets pass in sequence, A method for manufacturing an electrode, wherein the control step controls the rotation speed of the fan in each drying chamber to the same rotation speed.

4. In the first paragraph, the drying unit additionally includes a heater, A method for manufacturing an electrode, wherein the control step controls the operating conditions of the heater before stopping the coating section to be the same as the operating conditions of the heater when restarting the coating section.

5. In paragraph 1, a setting step of dividing the internal humidity of the drying section into multiple sections and setting the optimal rotation speed for each section; and An additional step of measuring the internal humidity of the drying section is included when the coating section is restarted after being stopped. The above control step is a method for manufacturing an electrode, wherein the control step searches for a section corresponding to the measured internal humidity of the drying section and controls the rotation speed of the fan inside the drying section at the set rotation speed of the searched section.

6. In the first paragraph, a collection step for collecting information on the weight of the electrode sheet coated with the electrode slurry before drying, the weight of the electrode sheet coated with the electrode slurry after drying, and the solid content of the electrode slurry coated on the electrode sheet after drying; and An electrode manufacturing method, comprising an evaluation step of evaluating whether the first rotation speed is appropriate based on the collected information.

7. In the 6th paragraph, the evaluation step is an electrode drying method in which the first rotation speed is evaluated as appropriate when the dry rate of the electrode calculated according to the following equations 1 and 2 is within the range of 80 to 99%: [Formula 1] [Formula 2] In the above formulas 1 and 2, M1 is the weight of the electrode sheet coated with the electrode slurry before drying, M1* is the average weight of the electrode sheet coated with the electrode slurry before drying, M2 is the weight of the electrode sheet coated with the electrode slurry after drying, M2* is the weight of the electrode sheet coated with the overdried electrode slurry after drying, and M3 is the solid content of the electrode slurry coated on the electrode sheet before drying.

8. A coating unit for coating electrode slurry on an electrode sheet transported in one direction; A drying unit that operates a fan supplying hot air at a preset first rotation speed and dries the electrode slurry coated on the electrode sheet through the hot air; and An electrode manufacturing device comprising a control unit that controls the operation of a coating unit and a drying unit, and controls the rotation speed of a fan in the drying unit to a second rotation speed lower than a first rotation speed based on the measured internal humidity of the drying unit when the coating unit is restarted after being stopped.

9. In the 8th paragraph, when the coating part is restarted after being stopped, when the measured internal humidity of the drying part is a second internal humidity lower than the first internal humidity before stopping or a third internal humidity lower than the second internal humidity, An electrode manufacturing device, wherein the control unit controls the rotation speed of the fan inside the drying unit to a second rotation speed at a second internal humidity, and controls the rotation speed of the fan inside the drying unit to a third rotation speed lower than the second rotation speed at a third internal humidity.

10. In the 8th paragraph, the drying unit includes a plurality of drying chambers through which the electrode sheets pass in sequence, An electrode manufacturing device in which the control unit controls the rotation speed of the fan in each drying chamber to the same rotation speed.

11. In the 8th paragraph, the drying unit additionally includes a heater, An electrode manufacturing device in which the control unit controls the operating conditions of the heater before stopping the coating unit and the operating conditions of the heater when restarting the coating unit to be the same.

12. An electrode manufacturing device, comprising a setting unit for dividing the internal humidity of a drying section into a plurality of sections and setting an optimal rotation speed for each section, in accordance with paragraph 8.

13. In the 12th paragraph, when the coating part is restarted after stopping, a measuring part is included to measure the internal humidity of the drying part, An electrode manufacturing device in which the above control unit searches for a section corresponding to the measured internal humidity of the drying section and controls the rotation speed of the fan inside the drying section at the set rotation speed of the searched section.

14. In the 8th paragraph, a collection unit for collecting information on the weight of the electrode sheet coated with the electrode slurry before drying, the weight of the electrode sheet coated with the electrode slurry after drying, and the solid content of the electrode slurry coated on the electrode sheet before drying; and An electrode manufacturing device, comprising an evaluation unit that evaluates whether the first rotation speed is appropriate based on the collected information.

15. In the 14th paragraph, the evaluation unit evaluates the first rotation speed as appropriate when the dry rate of the electrode calculated according to the following equations 1 and 2 is within the range of 80 to 99%, an electrode manufacturing device: [Formula 1] [Formula 2] In the above formulas 1 and 2, M1 is the weight of the electrode sheet coated with the electrode slurry before drying, M1* is the average weight of the electrode sheet coated with the electrode slurry before drying, M2 is the weight of the electrode sheet coated with the electrode slurry after drying, M2* is the weight of the electrode sheet coated with the overdried electrode slurry after drying, and M3 is the solid content of the electrode slurry coated on the electrode sheet before drying.

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