Electrode drying system and electrode drying method using the same

Abstract

The present invention relates to an electrode drying system and an electrode drying method using the same, which determines and controls an appropriate amount of heat to be supplied to a drying furnace having a dead time when an electrode is placed in the drying furnace based on previously calculated electrode drying data, thereby preventing excessive drying of the electrodes due to excess heat and preventing the occurrence of defects on the electrode surface.

Description

[Technical field]

[0001] This application claims the benefit of priority based on Korean Patent Application No. 10-2022-0166514 dated December 2, 2022, and all contents disclosed in the documents of that Korean patent application are incorporated herein by reference.

[0002] The present invention relates to an electrode drying system and an electrode drying method using the same. [Background technology]

[0003] In recent years, rechargeable secondary batteries have been widely used as energy sources for wireless mobile devices. Secondary batteries are also attracting attention as energy sources for electric vehicles and hybrid electric vehicles, which have been presented as a solution to address air pollution caused by existing gasoline and diesel vehicles that use fossil fuels. Therefore, the types of applications that use secondary batteries are becoming increasingly diverse due to the advantages of secondary batteries, and secondary batteries are expected to be applied to many more fields and products in the future.

[0004] Such secondary batteries may be classified into lithium ion batteries, lithium ion polymer batteries, lithium polymer batteries, etc., depending on the configuration of the electrodes and electrolyte, and the use of lithium ion polymer batteries, which are less likely to leak electrolyte and are easy to manufacture, is increasing. In general, secondary batteries are classified into cylindrical batteries and prismatic batteries in which an electrode assembly is housed in a cylindrical or prismatic metal can, and pouch batteries in which an electrode assembly is housed in a pouch case of an aluminum laminate sheet, depending on the shape of the battery case. The electrode assembly housed in the battery case is a chargeable and dischargeable power generating element having a positive electrode, a negative electrode, and a separator structure interposed between the positive electrode and the negative electrode, and is classified into a jelly roll type in which a separator is interposed between a long sheet-like positive electrode and a negative electrode coated with an active material and wound up, and a stack type in which a number of positive electrodes and negative electrodes of a predetermined size are stacked in sequence with a separator interposed between them.

[0005] The positive electrode and negative electrode are formed by applying a positive electrode slurry containing a positive electrode active material and a negative electrode slurry containing a negative electrode active material to a positive electrode current collector and a negative electrode current collector, respectively, to form a positive electrode active material layer and a negative electrode active material layer, and then drying and rolling the layers.

[0006] In this case, the drying conditions of the electrode affect the quality and physical properties of the electrode. In particular, the adhesive strength and surface bonding level of the electrode can change significantly depending on the dryness deviation in the width direction of the electrode during drying and the control of the drying completion time.

[0007] Meanwhile, the electrode coated with the electrode slurry undergoes a drying process while traveling through a drying section in a continuous process, but there may be a time interval between the electrode slurry coating process and the drying process for various reasons, and during the immobility time in the drying section where the electrode is not inserted into the drying oven, excess heat accumulates inside the drying oven. If the electrode is inserted into the drying oven in this state, cracks and wrinkles may occur in the electrode in the initial drying section due to the excessive heat accumulated in the drying oven.

[0008] In particular, electrode cracks caused by overdrying in the initial drying section generate electrode powder, which scatters far away along the hot air convection in the drying furnace and contaminates the surrounding electrodes, thereby degrading the quality of the electrodes. Therefore, it is very important to prevent overdrying in the initial drying section of the electrodes.

[0009] Therefore, it is necessary to develop an electrode drying technique that prevents excessive drying in the initial drying section. Summary of the Invention [Problem to be solved by the invention]

[0010] The present invention is made to solve the above problems, and provides an electrode drying system and an electrode drying method that, in a process of drying an electrode having a standstill time, prevents the electrode from being over-dried during initial drying due to excess heat accumulated in the drying furnace, thereby preventing cracks in the electrode. [Means for solving the problem]

[0011] The present invention provides an electrode drying system. In one example, the electrode drying system according to the present invention includes a drying oven for drying an electrode, and a dead time (T imm The amount of excess heat (Q res The control unit includes a data processing unit that calculates the normal quantity of heat (Q com , Common Quantity of Heat) to Excess Heat (Q res ) minus the heat supply (Q sup The drying furnace is characterized by supplying a certain quantity of heat (Supply Quantity of Heat) to the drying furnace.

[0012] In a specific example, the dryer control data is the immobility time (T imm ) and the amount of heat supplied (Q sup ) Includes the electrode drying rate according to

[0013] In another specific example, the data processing unit selects a stationary time (T imm ) is extracted, and the normal heat quantity (Q com ) to supply heat (Q sup ) minus the surplus heat (Q res ) is calculated.

[0014] In another specific example, the control unit determines the amount of excess heat (Q res ) remains while the heat supply (Q sup ) is controlled so that it increases over time.

[0015] In addition, the control unit calculates the amount of excess heat (Q res ) is not required, the normal heat amount (Q com ) is supplied.

[0016] In a specific example, the drying oven includes a hot air nozzle that supplies hot air to the electrodes to apply convection heat, and a heater that applies radiant heat to the electrodes.

[0017] Here, the control unit controls the amount of heat supplied to the drying oven by increasing or decreasing one or more of the following conditions: the temperature of the hot air sprayed from the hot air nozzle, the wind speed of the hot air, and the output of the heater.

[0018] In another specific example, the control unit controls the amount of heat supplied to the entire drying oven uniformly.

[0019] In another example, the electrode drying system of the present invention detects that the electrode is not fed into the drying oven and determines the dead time (T imm ) The sensor unit further includes a sensor section that transmits information to a data processing section.

[0020] In another example, the electrode drying system of the present invention further includes a measurement unit that collects dryness amount information of the electrode and sends the collected information to a control unit, and the control unit determines the dryness level of the electrode based on the dryness amount information received from the measurement unit and corrects the increase or decrease in the amount of heat supplied to the drying furnace in real time.

[0021] In a specific example, the measuring unit collects one or more of the solids content of the electrode and the temperature of the electrode surface before / after passing through a drying oven.

[0022] The present invention also provides an electrode drying method using the above-mentioned electrode drying system. In one example, the electrode drying method according to the present invention includes: (a) measuring the immobility time (T imm (b) collecting immobility time (T ) information from pre-calculated dry control data. imm The amount of excess heat (Q res(c) placing the electrode in a drying oven having a dead time; and (d) controlling the amount of heat supplied to the drying oven, and the (d) step includes a step of calculating a normal quantity of heat (Q com , Common Quantity of Heat) to Excess Heat (Q res ) minus the heat supply (Q sup The drying furnace is characterized by supplying a certain quantity of heat (Supply Quantity of Heat) to the drying furnace.

[0023] In a specific example, the dryer control data is the immobility time (T imm ) and the amount of heat supplied (Q sup ) Includes the electrode drying rate according to

[0024] In another specific example, in step (b), the immobility time (T imm ) is extracted, and the normal heat quantity (Q com ) to supply heat (Q sup ) minus the surplus heat (Q res ) is calculated.

[0025] In another specific example, in step (d), the excess heat (Q res ) remains, while the heat supply (Q sup ) is controlled so that it increases over time, and excess heat (Q res ) is not required, the normal heat amount (Q com ) is supplied. Effect of the Invention

[0026] According to the electrode drying system and electrode drying method using the same of the present invention, electrodes are placed in a drying furnace having a stationary time, and a lower amount of heat than is normally supplied during the initial drying time is supplied to the drying furnace, thereby suppressing over-drying of the electrodes due to excess heat, thereby preventing the occurrence of cracks in the electrodes and suppressing contamination inside the drying furnace, and the quality of the electrodes can be improved by supplying an optimal amount of heat to the drying furnace during the initial drying time based on previously calculated drying data. [Brief description of the drawings]

[0027] [Figure 1] 1 is a block diagram showing a configuration of an electrode drying system according to an embodiment of the present invention. [Diagram 2] 1 is a schematic diagram showing the structure of an electrode drying system according to one embodiment of the present invention. [Diagram 3] FIG. 11 is a block diagram showing a configuration of an electrode drying system according to another embodiment of the present invention. [Figure 4] FIG. 13 is a schematic diagram showing the structure of an electrode drying system according to another embodiment of the present invention. [Diagram 5] FIG. 2 is a schematic diagram showing the relationship between the electrode dryness rate and the amount of heat supply (Qsup) according to one example of the present invention. [Figure 6] 1 is a flowchart showing the steps of a method for drying an electrode according to one embodiment of the present invention. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0028] Since the present invention can be modified in various ways and can have various forms, specific embodiments are illustrated in the drawings and described in detail in the text, but this is not intended to limit the present invention to the specific disclosed forms, and it can be understood as including all modifications, equivalents, or alternatives within the spirit and technical scope of the present invention.

[0029] In this application, the terms "comprise" and "have" are intended to specify the presence of a feature, number, step, operation, component, part, or combination thereof described in the specification, and may be understood as not precluding the presence or addition of one or more other features, numbers, steps, operations, components, parts, or combinations thereof. In addition, when a part such as a layer, film, region, or plate is described as being "on" another part, this includes not only the case where it is "directly on" the other part, but also the case where there is another part in between. Conversely, when a part such as a layer, film, region, or plate is described as being "under" another part, this includes not only the case where it is "directly under" the other part, but also the case where there is another part in between. In addition, in this application, being "on" may include not only the case where it is located on the top, but also the case where it is located on the bottom.

[0030] The present invention provides an electrode drying system and an electrode drying method using the same.

[0031] Generally, an electrode coated with electrode slurry undergoes a drying process while traveling through a drying section in a continuous process. However, there may be a time interval between the electrode slurry coating process and the drying process for various reasons, and during the immobile time when the electrode is not inserted into the drying furnace in the drying section, excess heat is accumulated inside the drying furnace. If the electrode is inserted into the drying furnace in such a state that excess heat is accumulated, cracks and wrinkles may occur in the electrode in the initial drying section due to the excessive heat accumulated in the drying furnace. In particular, electrode cracks due to overdrying in the initial drying section will generate electrode powder, and the electrode powder will fly far away along the hot air convection in the drying furnace, contaminating the surrounding electrodes and reducing the quality of the electrode. Therefore, it is very important to prevent overdrying in the initial drying section of the electrode.

[0032] Therefore, in the present invention, in order to suppress the phenomenon that the electrode put into the drying oven having the immobility time is over-dried in the initial drying due to the excess heat accumulated in the drying oven during the drying process of the electrode having the immobility time, a heat amount that is reduced from the heat amount normally supplied to the drying oven is temporarily supplied during the initial drying time immediately after the electrode is put into the drying oven having the immobility time, and the heat amount is supplied with a difference in time series. Furthermore, drying control data having a condition closest to the immobility time condition on the line is derived from the drying control data calculated in advance, and the excess heat amount inside the drying oven during the immobility time is calculated from the derived drying control data. Then, the supply heat amount is calculated by subtracting the excess heat amount from the heat amount normally supplied via the control unit, and the supply heat amount is supplied into the drying oven. In this way, the supply heat amount supplied into the drying oven during the initial drying time is a heat amount that is reduced from the heat amount normally supplied, but is calculated taking into account the excess heat amount remaining in the drying oven.

[0033] The present invention is characterized in that, during the initial drying time after the electrodes are put into the drying oven having a dead time based on the drying control data in which the amount of heat supplied with time-series differences is calculated in advance, the amount of heat supplied into the drying oven is determined based on the drying control data under the conditions that best match the current conditions from among the data previously secured, and the amount of heat supplied into the drying oven is controlled. The determination of the amount of heat supplied into the drying oven can be performed automatically using a data processing unit and a control unit.

[0034] Hereinafter, an electrode drying system and an electrode drying method using the same according to the present invention will be described in detail.

[0035] FIG. 1 is a block diagram showing the configuration of an electrode drying system according to an embodiment of the present invention. FIG. 2 is a schematic diagram showing the structure of an electrode drying system according to an embodiment of the present invention. With reference to FIGS. 1 and 2, an electrode drying system 100 according to the present invention can be partitioned into a plurality of drying zones 111, 112, 113 along the x-axis, which is the direction in which an electrode 10 is transported, and includes a drying oven 110 for drying the electrode 10 and a dead time (T immThe amount of excess heat (Q res The drying oven 110 includes a data processing unit 120 that calculates the normal quantity of heat (Q com , Common Quantity of Heat) to Excess Heat (Q res ) minus the heat supply (Q sup , Supply Quantity of Heat) into the drying furnace 110.

[0036] In the present invention, the immobility time (T imm ) refers to a time interval during which the electrode 10 is not dried in the drying oven 110 or the electrode 10 is not fed into the drying oven 110 due to various process reasons. imm ) may specifically be 30 seconds to 30 minutes, 30 seconds to 20 minutes, or 1 minute to 15 minutes.

[0037] And the excess heat (Q res ) refers to the amount of heat accumulated in the drying furnace 110 while the introduction of the electrode 10 into the drying furnace 110 is interrupted.

[0038] And, the normal heat (Q com ) is the immobility time (T imm ) is not provided, the amount of heat normally supplied to the drying furnace 110.

[0039] And the heat supply (Q sup ) means the amount of heat supplied to the drying furnace 110, and the amount of heat supplied (Q sup ) is determined by the temperature of the hot air sprayed from the hot air nozzles located inside the drying oven, the speed of the hot air, and the amount of thermal energy supplied to the drying oven by the heater output.

[0040] The initial drying time is the normal heat amount (Q com) is supplied, specifically, it may mean a time interval from when the electrode 10 is placed in the drying oven 110 until 60 minutes have elapsed, or a time interval from when the electrode 10 is placed in the drying oven 110 until 30 minutes have elapsed, or a time interval from when the electrode 10 is placed in the drying oven 110 until 20 minutes have elapsed, or a time interval from when the electrode 10 is placed in the drying oven 110 until 10 minutes have elapsed, or a time interval from when the electrode 10 sheet is placed in the drying oven 110 until 5 minutes have elapsed. The length of the initial drying time is determined by the above immobility time (T imm ) depending on the length of the immobility time (T imm ) is relatively long, the excess heat (Q res ) may be excessive, which may result in a longer initial drying time and a longer immobilization time (T imm When the drying time is relatively short, the excess heat (Q res ) is relatively small, so the initial drying time can be shorter.

[0041] On the other hand, the surplus heat (Q res When the electrode 10 is placed in the drying furnace 110 in which excess heat (Q res ) may cause the electrode 10 to become overdried, which may induce cracks in the electrode 10. imm ), it is necessary to control the amount of heat supplied to the drying furnace 110 to be temporarily reduced, and at this time, it is necessary to appropriately select the amount of heat supplied while reducing it.

[0042] Therefore, the electrode drying system 100 of the present invention is configured to reduce the immobility time (T imm ) is stored, the excess heat (Q res ) to suppress the occurrence of cracks in the electrode 10. The control unit 130 of the present invention controls the immobility time (T immDuring the initial drying time after the electrode 10 is supplied to the drying oven 110 having the heating element 114, a heat amount that is reduced from the heat amount that is normally supplied to the drying oven 110 is temporarily supplied to the drying oven 110, and the heat amount to be supplied at this time is determined by the data processing unit 120 of the present invention.

[0043] Specifically, the data processing unit 120 of the present invention calculates the immobility time (T imm The amount of excess heat (Q res The data processing unit 120 calculates the immobility time (T imm ) coincides with the immobility time (T imm ) is extracted. Then, based on the extracted drying control data, the normal heat quantity (Q com ) to supply heat (Q sup ) minus the surplus heat (Q res ) is calculated. Here, the immobility time on the line (T imm ) is the immobility time (T imm )

[0044] The above drying control data is the immobility time (T imm ) by heat supply (Q sup ) and the electrode dryness rate information according to the amount of heat supplied (Q sup ) includes heat source output value information for determining the temperature, speed, and output value of the heater, etc.

[0045] In addition, the drying control data is recorded based on the time from when the infrared heater was activated to when it was idle (T imm The infrared heater may further include operating time and output value information of the infrared heater, which is the time until the electrode 10 is placed in the drying oven 110 having a drying oven 110 having a heating element 114, and may further include, as necessary, the product model name of the electrode 10 and indoor temperature information according to the season.

[0046] Specifically, the drying control data is stored in a specific immobility time (T immAfter the electrode 10 is placed in the drying furnace 110 having a different heat supply amount (Q sup ) is applied to the electrode 10 while drying the electrode 10. sup ) and the electrode dryness rate are described in detail below.

[0047] To give an example, in the drying control data, the immobility time (T imm The initial drying time T, which is a certain time after the electrode 10 is inserted into the drying furnace 110 having a temperature of 1000° C., is divided into n (n≧2) time intervals in a chronological order, and the amount of heat (Q sup ) can be defined as Q1, Q2, Q3, ... Qn, and the electrode dryness rates in each time interval can be defined as Y1, Y2, Y3, ... Yn.

[0048] Then, the excess heat (Q res Assuming that the time intervals during which excess heat (Q res Assuming that the time intervals T6, T7...T10 are the time intervals in which no heat remains, the amount of heat supplied in the first time interval T1 (Q sup )Q1 is usually the amount of heat (Q com ) is reduced by (Q com >Q1), and the heat supply amount (Q sup ) Q2 has a somewhat increased value compared to Q1 and is usually com ) is smaller than (Q com >Q2>Q1). In addition, the heat supply amounts (Q sup ) Q3, Q4 and Q5 are the same as Q2 above, with their values ​​(Q com >Q5>Q4>Q3>Q2>Q1). Thus, the immobility time (T imm In the drying furnace 110 having the excess heat (Q res ) when there is a quantity of heat (Q com) and then gradually / stepwise increasing the amount of heat supplied over time to prevent initial over-drying of the electrode 10.

[0049] On the other hand, the excess heat (Q res The heat quantity in each of the time intervals T6, T7…T10, where no heat remains, is Q com The relationship between Q6, Q7, Q8, Q9, and Q10 may be satisfied. This means that the amount of excess heat (Q res ) does not remain, the amount of heat supplied to the drying furnace 110 is the normal amount of heat (Q com ) in each time interval. In other words, the drying control data is the amount of excess heat (Q res ) is taken into account, the amount of heat supplied (Q sup ) is determined.

[0050] To explain this in more detail with another example, in the drying control data, the electrode dryness rates in each time interval T1, T2, T3, ... Tn are defined as Y1, Y2, Y3, ... Yn, and among the electrode dryness rates in each time interval, the dryness rate closest to a preset target electrode dryness rate is assumed to be Y5. Then, the heat amounts in T1, T2 ... T5 are Q1 <Q2<Q3<Q4<Q5<Q com The heat quantities at T6, T8, T10 are Q6=Q7=Q8=Q9=Q10=Q com That is, in the time interval having the electrode dryness rate closest to the target electrode dryness rate, there is a high probability that no residual heat will remain in the drying furnace 110. Reflecting this predicted behavior, in the time interval before the time interval having the electrode dryness rate closest to the target electrode dryness rate, the normal heat amount (Q com ) with less heat supply (Q sup ) is determined, and in the following time interval, the amount of heat (Q com ) with the same amount of heat supplied (Q sup ) can be determined.

[0051] FIG. 5 shows the amount of heat supplied (Q sup FIG. 2 is a schematic diagram showing the relationship between the electrode dryness rate and the temperature at which the electrode is dried.

[0052] Referring to FIG. 5, the amount of heat supplied (Q sup ) can be adjusted, for example, by controlling the output value of the infrared heater. Increasing the output value of the infrared heater increases the amount of heat supplied (Q sup ) increases, and conversely, when the output value of the infrared heater is decreased, the amount of heat supplied (Q sup ) decreases. At this time, the output value of the infrared heater in each time interval is determined by proportional control (P control) with respect to the electrode dryness rate. The proportional control (P control) refers to controlling the manipulated variable in proportion to the difference between a target value and a current value. Here, the target value corresponds to the target electrode dryness rate, the current value corresponds to the electrode dryness rate in the previous time interval, and the manipulated variable corresponds to the amount of change in the amount of heat supplied (or the output value of the infrared heater).

[0053] 5, in relation to the maximum electrode drying rate, which is the drying rate at which the electrode product model to be dried can be maximally dried, and the target electrode drying rate, the variation (X%) between the amount of heat (or infrared heater output value) supplied in the previous time interval and the amount of heat (or infrared heater output value) supplied in the specific time interval is determined in proportion to the deviation (X%) between the electrode drying rate in the previous time interval and the target electrode drying rate. That is, when the deviation between the electrode drying rate in the specific time interval and the target electrode drying rate is relatively large, it can be said that the amount of heat (or infrared heater output value) supplied in the specific time interval shows a relatively large variation compared to the amount of heat (or infrared heater output value) supplied in the previous time interval. On the other hand, when the deviation between the electrode drying rate in the specific time interval and the target electrode drying rate is relatively small, it can be said that the amount of heat (or infrared heater output value) supplied in the specific time interval shows a relatively small variation compared to the amount of heat (or infrared heater output value) supplied in the previous time interval. This behavior allows fine adjustment of the electrode dryness rate as the amount of fluctuation in the amount of heat supplied (or the output value of the infrared heater) in a specific time period decreases (proportional control) as the electrode dryness rate in the previous time period reaches the target electrode dryness rate.

[0054] However, if the electrode dryness rate in the previous time interval is equal to or exceeds the target electrode dryness rate (if it is overdried), the amount of heat to be supplied (or the infrared heater output value) in the specific time interval is not determined by the proportional control (P control) described above, and the amount of heat to be supplied (or the infrared heater output value) in the specific time interval is determined to be equal to the amount of heat to be supplied (or the infrared heater output value) in the previous time interval. This is because the electrode dryness rate in the specific time interval has already reached or exceeded the target electrode dryness rate, so the amount of heat to be supplied (or the infrared heater output value) is increased to prevent the electrodes from being overdried, and a constant amount of heat is supplied to the drying furnace to improve the uniformity of electrode quality.

[0055] In addition, if the electrode drying rate in the previous time section is less than the target electrode drying rate (if the electrode is insufficiently dried), the excess heat (Q res On the other hand, if the electrode drying rate in the specific time period exceeds the target electrode drying rate (if the electrode is dried excessively), excess heat (Q res In general, the target electrode drying rate is determined by the amount of excess heat (Q res ) remains or not.

[0056] Returning to the data processing unit 120 of the present invention, the data processing unit 120 selects the immobility time on the line (T imm ) closest to the immobility time (T imm ) to extract the drying control data having the immobility time (T imm In addition to the immobility time (T imm ) before the electrode is placed in a drying oven having a drying temperature of 100° C., the drying control data that matches one or more of the following conditions can be extracted: the operation time and output value of the infrared heater, the product model name of the electrode 10, and the indoor temperature according to the season. That is, the immobility time on the line (T imm ) closest to the immobility time (T imm) and at the same time, drying control data having the same infrared heater operating time and output value as the infrared heater on the line can be extracted. Alternatively, the immobility time on the line (T imm ) closest to the immobility time (T imm ) and at the same time, it is possible to extract drying control data that matches the operating hours of the infrared heaters on the line and the product model names of the electrodes.

[0057] At this time, the data processing unit 120 calculates the immobility time (T imm ) coincides with the immobility time (T imm The drying control data having the information is searched for. The search grid is a machine learning model in which the desired conditions are parameters, and various combinations of the parameters are tried to obtain the optimal parameters. Here, the parameter is the immobility time (T imm ) can be used as the parameter for the above. imm ) was used as an example, but immobility time (T imm ) conditions, immobility time (T imm The conditions may further include one or more of the operating time and output value of the infrared heater, the product model name of the electrode 10, and the indoor temperature according to the season, until the electrode is placed in a drying furnace having a temperature sensor, and optimal drying control data that matches the conditions may be detected.

[0058] In addition, the data processing unit 120 extracts drying control data that meets the conditions, and calculates the amount of heat supply (Q sup ) and normal heat (Q com ) and the excess heat (Q res ) can be calculated.

[0059] The control unit 130 of the present invention controls the amount of heat supplied to the drying furnace 110. At this time, the control unit 130 controls the amount of surplus heat (Q res ) information is taken into consideration to control the amount of heat supplied to the drying furnace 110, and the normal amount of heat (Q com) to the excess heat (Q res ) minus the heat supply (Q sup ) is supplied into the drying furnace 110.

[0060] Specifically, the excess heat quantity (Q res ) information is obtained from the drying control data by calculating the immobility time (T imm ) with the same immobility time (T imm ) and can be said to be most consistent with the heat quantity conditions configured in the drying oven 110 on the line. Therefore, the supply heat quantity (Q sup ) is the amount of heat supplied for each time interval of the detected drying control data (Q sup ) and the amount of heat supplied for each time interval of the drying control data (Q sup ) can be determined according to the output value of a heat source, such as the output value of an infrared heater, derived through proportional control (P control). However, the amount of heat (Q sup ) is the real-time information on the electrode dryness or immobility time (T imm ) can be corrected based on various conditions other than the above.

[0061] In addition, the control unit 130 controls the amount of excess heat (Q res ) remains, while the heat supply (Q sup The drying furnace 110 is characterized in that the amount of excess heat (Q res ), the drying furnace 110 is normally supplied with heat (Q com The drying furnace 110 is controlled so that the excess heat (Q res ) remains, usually the amount of heat (Q com ) to the excess heat (Q res ) minus the heat supply (Q sup ) is supplied to the drying furnace 110, but the surplus heat (Q res ) depending on the degree of heat supply (Q sup ) is determined. In general, the immobility time (T immThe electrode 10 is placed in a drying furnace 110 having a temperature of 1000° C., and after a certain period of time, the excess heat (Q res ) will decrease, so the control unit 130 controls the supply of heat (Q sup On the other hand, the amount of heat remaining in the drying furnace 110 (Q res ), the amount of heat (Q com ) is supplied into the drying furnace 110.

[0062] The control unit 130 determines the amount of excess heat (Q res ) remains, the reduced amount of heat is supplied to the drying oven 110, thereby controlling the amount of heat supplied to the drying oven 110 uniformly throughout the drying oven 110. imm ), the excess heat (Q res ) is accumulated, so the excess heat (Q res In order to attenuate the above-mentioned problem, it is preferable to perform the above-mentioned control uniformly over the entire drying furnace 110.

[0063] The configuration of the electrode drying system 100 according to the present invention will be described in detail below.

[0064] 1, an electrode drying system 100 according to the present invention includes a drying oven 110. The drying oven 110 is in the form of a chamber, provides a space for an electrode 10 to be dried to move inside the drying oven 110, and prevents internal heat for drying from escaping to the outside.

[0065] Meanwhile, the electrode may have a structure in which an electrode active material layer is formed by coating an electrode forming slurry containing an electrode active material on an electrode collector. The electrode slurry may be coated on at least one surface of the collector.

[0066] In this case, the electrode current collector may be a positive electrode current collector or a negative electrode current collector, the electrode active material may be a positive electrode active material or a negative electrode active material, and the electrode slurry may further include a conductive material and a binder in addition to the electrode active material.

[0067] In the present invention, the positive electrode current collector is generally made to a thickness of 3 to 500 μm. Such a positive electrode current collector is not particularly limited as long as it has high conductivity without inducing chemical changes in the battery, and for example, stainless steel, aluminum, nickel, titanium, baked carbon, or aluminum or stainless steel surface-treated with carbon, nickel, titanium, silver, etc. may be used. The current collector may have fine irregularities on its surface to increase the adhesive force of the positive electrode active material, and may be in various forms such as a film, sheet, foil, net, porous body, foam, nonwoven fabric, etc.

[0068] In the case of a sheet for a negative electrode current collector, it is generally made to a thickness of 3 to 500 μm. Such a negative electrode current collector is not particularly limited as long as it is conductive and does not induce chemical changes in the battery, and for example, copper, stainless steel, aluminum, nickel, titanium, baked carbon, copper or stainless steel surface-treated with carbon, nickel, titanium, silver, etc., aluminum-cadmium alloy, etc. can be used. In addition, like the positive electrode current collector, fine irregularities can be formed on the surface to strengthen the binding force of the negative electrode active material, and it can be used in various forms such as a film, sheet, foil, net, porous body, foam, nonwoven fabric, etc.

[0069] In the present invention, the positive electrode active material is a material capable of undergoing an electrochemical reaction, and contains two or more transition metals as a lithium transition metal oxide, for example, a layered compound such as lithium cobalt oxide (LiCoO2) or lithium nickel oxide (LiNiO2) substituted with one or more transition metals; a lithium manganese oxide substituted with one or more transition metals; a compound represented by the chemical formula LiNi 1-y M yLithium nickel oxide represented by LiO2 (wherein M=Co, Mn, Al, Cu, Fe, Mg, B, Cr, Zn or Ga, containing one or more of the above elements, and 0.01≦y≦0.7); 1+z Ni 1 / 3 Co 1 / 3 Mn 1 / 3 O2, Li 1+z Ni 0.4 Mn 0.4 Co 0.2 O2, etc., Li 1+z Ni b Mn c Co 1-(b+c+d) M d O (2-e) A e (wherein, -0.5≦z≦0.5, 0.1≦b≦0.8, 0.1≦c≦0.8, 0≦d≦0.2, 0≦e≦0.2, b+c+d<1, M=Al, Mg, Cr, Ti, Si or Y, and A=F, P or Cl); 1+x M 1-y M' y PO 4-z X z (wherein M=transition metal, preferably Fe, Mn, Co, or Ni; M′=Al, Mg, or Ti; X=F, S, or N; −0.5≦x≦+0.5; 0≦y≦0.5; 0≦z≦0.1), but is not limited thereto.

[0070] The negative electrode active material is, for example, carbon such as non-graphitizable carbon or graphite-based carbon; Li x Fe2O3(0≦x≦1), Li x WO2(0≦x≦1), Sn x Me 1-x Me' y O zMetal composite oxides such as (Me: Mn, Fe, Pb, Ge; Me’: Al, B, P, Si, Group 1, Group 2, Group 3 elements of the periodic table, halogens; 0 < x ≦ 1; 1 ≦ y ≦ 3; 1 ≦ z ≦ 8); lithium metal; lithium alloy; silicon-based alloy; tin-based alloy; metal oxides such as SnO, SnO2, PbO, PbO2, Pb2O3, Pb3O4, Sb2O3, Sb2O4, Sb2O5, GeO, GeO2, Bi2O3, Bi2O4, Bi2O5; conductive polymers such as polyacetylene; Li-Co-Ni-based materials, etc. may be used.

[0071] The above conductive material is usually added at 1 to 30% by weight based on the total weight of the mixture containing the positive electrode active material. Such a conductive material is not particularly limited as long as it has conductivity without inducing a chemical change in the battery. For example, graphite such as natural graphite and artificial graphite; carbon black such as carbon black, acetylene black, ketjen black, channel black, furnace black, lamp black, thermal black; conductive fibers such as carbon fibers and metal fibers; metal powders such as carbon fluoride, aluminum, nickel powder; conductive whiskers such as zinc oxide, potassium titanate; conductive metal oxides such as titanium oxide; conductive materials such as polyphenylene derivatives, etc. may be used.

[0072] The above binder is a component that promotes the bonding of the active material and the conductive material, etc. and the bonding to the current collector, and is usually added at 1 to 30% by weight based on the total weight of the mixture containing the positive electrode active material. Examples of such binders include polyvinylidene fluoride, polyvinyl alcohol, carboxymethyl cellulose (CMC), starch, hydroxypropyl cellulose, regenerated cellulose, polyvinylpyrrolidone, tetrafluoroethylene, polyethylene, polypropylene, ethylene-propylene-diene terpolymer (EPDM), sulfonated EPDM, styrene-butadiene rubber, fluororubber, various copolymers, etc.

[0073] Meanwhile, such an electrode slurry may be prepared by dissolving an electrode active material, a conductive material, a binder, and the like in a solvent. The type of the solvent is not particularly limited as long as it can disperse the electrode active material, and either an aqueous solvent or a non-aqueous solvent can be used. For example, the solvent may be a solvent commonly used in the art, such as dimethyl sulfoxide (DMSO), isopropyl alcohol, N-methylpyrrolidone (NMP), acetone, or water, and one or a mixture of two or more of these may be used. The amount of the solvent used is not particularly limited as long as it can be adjusted to a level that allows the slurry to have a suitable viscosity in consideration of the coating thickness of the slurry, production yield, workability, and the like.

[0074] Referring to FIG. 2, the drying oven 110 may be divided into a plurality of drying zones, and each drying zone includes a hot air nozzle 114 that supplies hot air to the electrode 10 to apply convection heat, and a heater that applies radiant heat to the electrode 10, as drying means for drying the electrode 10 therein. Referring to FIG. 2, the hot air nozzle 114 and the heater 115 may be arranged at regular intervals along the transport direction (MD direction, x direction) of the electrode 10, and apply hot air or radiant heat in a direction perpendicular to the electrode 10. In FIG. 2, the hot air nozzle 114 and the infrared heater are shown to be located above the electrode 10, i.e., on the underside of the ceiling of the drying oven 110, but when the electrode active material layer 12 is formed on both sides of the current collector, the hot air nozzle 114 and the heater 115 may be located above and below the electrode 10, respectively. In addition, the embodiment shown in FIG. 2 illustrates a case in which both the hot air nozzle 114 and the heater are included as drying means, but only one of them may be included. Meanwhile, the hot air nozzle 114 includes a main body and an ejection part. The main body constitutes the main body of the hot air nozzle 114, and the hot air nozzle 114 is fixed to the ceiling of the drying oven 110. The main body is hollow inside and transmits hot air transmitted from a hot air supply source (not shown) to the ejection part. Meanwhile, the ejection part is provided on the bottom surface of the main body. The ejection part is connected to the main body, and an ejection port is formed on the bottom surface of the ejection part through which the hot air is ejected. The ejection port may have a structure in which a plurality of holes are arranged at regular intervals.

[0075] Meanwhile, the heater 115 may be an infrared heater in a specific example of the present invention, and the infrared heater may include an infrared heater that irradiates infrared rays to the electrode 10, and a support that supports or mounts the infrared heater. The shape of the infrared heater is not particularly limited, and for example, rod-shaped heaters may be arranged in parallel along the transfer direction of the electrode 10 with the heaters extending in the width direction of the electrode 10.

[0076] The hot air nozzles 114 and heaters 115 may be alternately arranged along the moving direction of the electrode 10 in order to uniformly supply hot air and infrared rays to the surface of the electrode 10. However, there is no particular limitation on the arrangement form, and a skilled artisan may suitably change the design of the arrangement of the hot air nozzles 114 and infrared heaters depending on the drying conditions.

[0077] The drying system 100 of the present invention can control the amount of heat supplied to the drying furnace 110 by increasing or decreasing one or more of the following conditions: the temperature of the hot air sprayed from the hot air nozzle 114, the wind speed of the hot air, and the heater output.

[0078] In addition, the drying oven 110 may include one or more transport rollers 116 for transporting the electrode 10. A plurality of the transport rollers 116 may be arranged at regular intervals along the transport direction of the electrode 10, support the electrode 10 during the drying process, and transport the electrode 10 after the drying is completed to the outside of the drying oven 110. In addition, the drying amount of the electrode 10 may be controlled by manipulating the rotation speed of the transport rollers 116.

[0079] The electrode drying system 100 according to the present invention detects that the electrode 10 is not fed into the drying oven 110 and measures the dead time (T imm The drying oven 110 further includes a sensor unit 140 that transmits information about the electrode 10 to the data processing unit 120. The sensor unit 140 may be installed around an entrance of the drying oven 110 where the electrode 10 is inserted. The sensor unit 140 includes a detection sensor that detects the movement of the electrode 10, and the type of the detection sensor is not limited as long as it can detect whether the electrode 10 is inserted. Therefore, the detection sensor may be a type that detects weight or an image camera type.

[0080] The control unit 130 of the present invention is connected to the first operation control unit 117, the second operation control unit 118 and the third operation control unit 119 installed in the first drying zone 111, the second drying zone 112 and the third drying zone 113, respectively, and can thereby command a reduction in the amount of heat supplied thereto. The control unit 130 receives the immobility time (T immThe amount of excess heat (Q res ) information is received, and the amount of heat (Q sup ) is determined, and the determined amount of heat to be supplied (Q sup ) into the drying oven 110. In response to this, the operation control units 117, 118, and 119 of the drying oven 110 control the supply of the instructed heat amount (Q sup ) The amount of heat supplied is controlled according to the information.

[0081] FIG. 3 is a block diagram showing the configuration of an electrode drying system 200 according to another embodiment of the present invention, and FIG. 4 is a schematic diagram showing the structure of the electrode drying system 200 according to another embodiment of the present invention. With reference to FIG. 3 and FIG. 4, the electrode drying system 200 of the present invention includes a drying oven for drying the electrode 10, and a dead time (T imm The amount of excess heat (Q res ) and a control unit 230 that controls the amount of heat supplied to the drying oven. The control unit 230 controls the amount of heat (Q com ) to the excess heat (Q res ) minus the heat supply (Q sup ) into the drying oven. Furthermore, the electrode 10 is detected as not being fed into the drying oven and the dead time (T imm The drying oven further includes a sensor unit 240 that transmits information on the drying amount of the electrode 10 to the data processing unit 220, and a measurement unit that collects information on the drying amount of the electrode 10 and transmits the collected information to the control unit 230, and the control unit 230 determines the dryness level of the electrode 10 according to the dryness amount information received from the measurement unit, corrects the increase or decrease in the amount of heat supplied to the drying oven in real time, and controls the amount of heat supplied to the drying oven according to the corrected amount of heat. The control unit 230 is also connected to a first operation control unit 217, a second operation control unit 218, and a third operation control unit 219 installed in the first drying zone 211, the second drying zone 212, and the third drying zone 213, respectively, and can thereby command a decrease in the amount of heat supplied thereto.

[0082] Such an electrode drying system 200 has a dead time (T imm When the electrode 10 is put into the drying furnace after the lapse of 1000 hours, the excess heat (Q res ) remains while the usual heat (Q com ) to prevent over-drying in the initial stage, while supplying excess heat (Q res ) no longer remains, the dryness amount of the electrode 10 can be corrected according to the dryness level of the electrode 10, thereby making the dryness level of the electrode 10 uniform. That is, the measuring units 250; 250a, 250b collect dryness amount information of the electrode 10 in real time, the control unit 230 judges the dryness level of the electrode 10 based on the collected dryness amount information, and the dryness amount can be periodically corrected according to the dryness level of the electrode 10, thereby making it possible to control the dryness level of the electrode 10 uniformly.

[0083] The dryness information is one or more of the solid content of the electrode 10 and the temperature of the electrode surface. The electrode drying system 200 of the present invention determines the dryness level of the electrode 10 through the solid content and / or temperature collected via a measurement unit. The measurement unit may include one or more of a web-gauge and a temperature measuring device that measures the loading amount of the electrode 10 to collect the solid content and the temperature of the electrode surface.

[0084] 4, the measuring units 250a and 250b may include a web-gauge for measuring the loading amount of the electrode 10, and may be installed at the inlet and outlet of a drying oven, respectively, to measure the loading amount of the electrode 10 before drying and the loading amount of the electrode 10 after drying. The measuring units 250a and 250b may further include a calculation unit for deriving the solid content, and the calculation unit may derive the solid content of the electrode active material layer 12 from the measured loading amount through a calculation formula input in advance. The formula for deriving the solid content from the loading amount may be one known in the art.

[0085] If the dryness level of the electrode 10 is excessive (over-dried), the solid content will be higher than the standard value, and if the dryness level of the electrode 10 is insufficient (not yet dried), the solid content will be lower than the standard value. Therefore, the solid content can be an indicator for understanding the dryness level of the electrode 10.

[0086] The control unit 230 can determine the dryness level of the electrode 10 based on the dryness information received from the measuring units 250a, 250b, and control the amount of heat supplied to the drying oven according to the determined dryness level, thereby correcting the dryness of the electrode 10 in real time.

[0087] In order for the control unit 230 to correct the dryness amount of the electrode 10 in real time, the measuring units 250a, 250b are set to periodically collect dryness amount information of the electrode 10 at regular time intervals, and the control unit 230 determines the dryness level of the electrode 10 each time it receives dryness amount information from the measuring units 250a, 250b, and periodically controls the amount of heat supplied to the drying furnace.

[0088] The process of controlling the drying amount by the control unit 230 will be described in detail. The control unit 230 may receive drying amount information such as the loading amount before / after drying of the electrode 10 and / or the temperature of the electrode surface from the measurement units 250a and 250b, and may input a reference value for determining whether the drying level of the electrode 10 is overdried or not dried. The control unit 230 may compare the drying amount information with the reference value to determine whether the drying level of the electrode 10 is overdried, not dried, or normal dried, and may quantitatively grasp the degree of overdried or not dried by comparing the drying amount information with the reference value, and may determine a method of controlling the drying intensity. When the drying level and drying amount of the electrode 10 are determined in this manner, the control unit 230 may correct the drying amount of the electrode 10 by controlling one or more of the hot air nozzle 214, the heater 215, and the traveling speed of the transport roller 216 through which the electrode 10 travels in order to increase or decrease the drying intensity of the drying oven.

[0089] The control of the drying intensity by the control unit 230 is not limited to one time, but is periodically performed at regular time intervals. In one specific example, the control unit 230 may repeatedly control the drying intensity of the drying oven at a cycle of 5 to 20 minutes, and may preferably control the drying intensity at a cycle of 6 to 15 minutes, but the control cycle of the drying intensity is not limited thereto.

[0090] The measuring units 250a and 250b are also set to periodically collect dryness amount information of the electrode 10 at regular time intervals in conjunction with the drying intensity control by the control unit 230. In one specific example, the measuring units 250a and 250b collect dryness amount information for 1 to 5 minutes immediately before the time when the drying intensity control by the control unit 230 is scheduled. That is, the measuring units 250a and 250b do not collect dryness amount information of the electrode 10 immediately after the control unit 230 controls the drying intensity of the drying oven, but collect dryness amount information of the electrode 10 after the control unit 230 controls the drying intensity and a certain time has elapsed. This is because a certain time is required until the dryness amount correction effect due to the change in the drying intensity of the drying oven appears.

[0091] The measuring units 250a, 250b can send the average or median value of the dryness amount information collected during the predetermined time to the control unit 230 as a representative value of the dryness amount information.

[0092] Moreover, the measuring units 250a and 250b may include a temperature measuring device capable of measuring the temperature of the electrode surface. By measuring the temperature inside the drying oven, the amount of heat supplied to the drying oven can be controlled more precisely.

[0093] The present invention also provides an electrode drying method using the above-mentioned electrode drying system.

[0094] FIG. 6 is a flow chart showing the procedure of the electrode drying method according to the present invention.

[0095] Referring to FIG. 6, in one example, the electrode drying method of the present invention includes: (a) a stationary time (T imm(b) collecting immobility time (T ) information from pre-calculated dry control data. imm The amount of excess heat (Q res (c) calculating the immobility time (T imm ), and (d) controlling the amount of heat supplied to the drying oven, and the (d) step is usually com , Common Quantity of Heat) to Excess Heat (Q res ) minus the heat supply (Q sup , Supply Quantity of Heat) is supplied to the drying furnace.

[0096] The above step (a) is a time during which the electrodes are not dried in the drying oven on the line (T imm ) information is collected. As described above, this information can be sensed by a sensor unit installed around the entrance of the drying oven.

[0097] The above step (b) selects the immobility time (T imm ) closest to the immobility time (T imm ) is extracted, and based on the extracted drying control data, a normal heat quantity (Q com ) to supply heat (Q sup ) minus the surplus heat (Q res That is, in step (b), the condition closest to the current condition is calculated from the drying control data calculated in advance, and the condition here is the immobility time (T imm ), extracting drying control data having a condition closest to the current condition, and calculating a dead time (T imm The amount of excess heat (Q res) is calculated. Then, when the initial drying time is divided into multiple time intervals in a chronological order, the amount of excess heat remaining in the drying oven in each time interval (Q res ) is calculated. The surplus heat (Q res ) is sent to the control unit.

[0098] In the above step (d), the surplus heat (Q res ) is the immobility time on the line (T imm The predicted amount of excess heat (Q res Therefore, the control unit usually uses the heat quantity (Q com ) to the excess heat (Q res ) minus the heat supply (Q sup ) is fed into the drying furnace.

[0099] The above step (d) generates excess heat (Q res ) while remaining heat supply (Q sup ) is controlled so that it increases over time, and excess heat (Q res ) is not required for the drying oven to have normal heat (Q com In other words, the excess heat (Q res ) remains while the usual heat (Q com ) and the surplus heat (Q res Considering the amount of heat supplied (Q sup Heat is supplied so that the magnitude of the heat (Q res ), the amount of heat (Q com ) is supplied to the drying furnace.

[0100] Hereinafter, the electrode drying system and the electrode drying method using the same of the present invention will be described in more detail with reference to examples of the present invention.

[0101] (Example)

[0102] The following Table 1 is an example of pre-calculated drying control data. imm After inserting the electrodes into the drying oven, the output value and the amount of heat (Q sup ) shows the electrode drying rate according to

[0103] [Table 1]

[0104] Referring to Table 1 above, the immobility time (T imm ) means the time during which the electrodes are not dried in the drying oven or the electrodes are not inserted in the drying oven. imm ) (wherein sequence "0" refers to a case where no electrode is placed in the drying oven, and sequence "1" refers to a case where an electrode is placed in the drying oven). And the infrared heater output value refers to an output intensity value at which the infrared heater emits thermal energy. Here, the output value ranges from 0 to 25. The first heater to the fourth heater are infrared heaters that are installed sequentially in the electrode transfer direction in a part of the drying zone. Meanwhile, in the embodiment, an infrared heater is taken as an example of a heat source that supplies heat to the drying oven, but the present invention is not limited thereto. The supply heat amount (Q sup ) is the percentage of the infrared heater output in the corresponding order relative to the maximum output of the infrared heater, and the excess heat (Q res ) is usually expressed as heat (Q com ) is set to 100%, the normal heat (Q com ) to supply heat (Q sup ) is subtracted from the value.

[0105] In Table 1, the output value of the infrared heater in the current sequence may be determined according to the deviation between the electrode dryness rate in the previous sequence and the target electrode dryness rate. The process of deriving the infrared heater output value in the current sequence will be specifically described with reference to the following Tables 2 and 3.

[0106] Table 2 below is intended to explain a proportional control (P control) method for deriving an infrared heater output value to be applied to the current sequence from pre-calculated drying control data when the electrode dryness rate in the previous sequence is lower than the target electrode dryness rate, and shows various electrode dryness rate information and infrared heater output value information.

[0107] [Table 2]

[0108] The maximum electrode dryness rate in Table 2 above means the maximum electrode dryness rate set as the limit in the electrode model to be dried. The maximum electrode dryness rate is a criterion for determining the degree of deviation between the dryness rate in the previous sequence and the target electrode dryness rate. Referring to Table 2 above, in number 1, the output value change amount (6.7%) for the infrared heater output value (80%) in the previous sequence is determined in proportion to the deviation (3%) between the electrode dryness rate in the previous sequence (82%) and the target electrode dryness rate (85%), and thus the infrared heater output value (86.7%) applied in the current sequence is determined.

[0109] In number 2, the output value change amount (5%) relative to the infrared heater output value (80%) in the previous step is determined in proportion to the deviation (2%) between the electrode dryness rate in the previous step (83%) and the target electrode dryness rate (85%), and thus the infrared heater output value (85%) to be applied in the current sequence is determined. Number 2 has a smaller deviation between the electrode dryness rate in the previous sequence and the target electrode dryness rate than number 1. Therefore, it can be observed that number 2 shows a smaller range of change in the infrared heater output value applied in the current sequence compared to number 1.

[0110] In number 3, the output value change amount (2.9%) relative to the infrared heater output value (80%) in the previous step is determined in proportion to the deviation (1%) between the electrode dryness rate in the previous step (84%) and the target electrode dryness rate (85%), and thus the infrared heater output value (82.9%) to be applied in the current sequence is determined. It can be observed from number 3 that the infrared heater output value applied in the current sequence shows a smaller range of change compared to the infrared heater output value applied in the previous sequence than in number 2.

[0111] Table 3 below illustrates an exception to the proportional control (P control) method, which derives the infrared heater output value to be applied to the current sequence from pre-calculated drying control data when the electrode dryness rate in the previous sequence is the same as or greater than the target electrode dryness rate, and shows various electrode dryness rate information and infrared heater output value information.

[0112] [Table 3]

[0113] Referring to Table 3 below, in case 1, the electrode dryness rate in the previous step (85%) is the same as the target electrode dryness rate (85%). That is, this corresponds to the case where the electrode dryness rate in the previous step reaches the target electrode dryness rate. In this case, the infrared heater output value applied in the current sequence is determined to be the same value as the infrared heater output value applied in the previous sequence. If the infrared heater output value applied in the current sequence is increased, the electrode may become over-dried, so the infrared heater output value applied in the previous sequence is maintained. In case 2, the electrode dryness rate in the previous sequence (86%) exceeds the target electrode dryness rate (85%). That is, this corresponds to the case where the electrode is over-dried in the previous sequence. In this case as well, like case 1, the infrared heater output value applied in the current sequence is determined to be the same value as the infrared heater output value applied in the previous sequence.

[0114] Referring again to Table 1, the dead time (T immWhen the immobility time (T) is 154 minutes, the data processing unit selects the immobility time (T) in Table 1 from the previously calculated drying control data. imm The drying control data calculated in advance when the immobility time (T) is 154 minutes is derived using a search grid method. imm In the embodiment, the pre-calculated drying control data is not derived when the immobility time (T imm ) information is used as a variable, but it is not limited to this. imm In addition to the immobility time (T imm Any one of the following information may be set as an additional variable: the output value of the infrared heater operated during the drying process, the product name of the electrode to be dried, or the temperature outside the drying oven.

[0115] The data processing unit calculates the infrared heater output value and the amount of heat supplied (Q sup ), excess heat (Q res ) and electrode dryness rate, and the amount of excess heat (Q res ) is calculated. The excess heat applied on the line (Q res The method for calculating the excess heat (Q res ) The calculation may be made by directly reflecting the information or by carrying out a correction process as necessary.

[0116] The following description of the data processing section will be given on the assumption that the correction process is not required.

[0117] The control unit determines and controls the amount of heat to be supplied to the drying oven based on the information derived from the data processing unit. The amount of heat to be supplied to the drying oven can be determined according to the output value of the infrared heater, which corresponds to the magnitude of the thermal energy radiated from the infrared heater, as described above.

[0118] Specifically, the control unit detects the excess heat (Q res ) based on the immobility time on the line (T immThe control unit determines the amount of heat to be supplied to the drying furnace for 7 minutes after the electrode is inserted into the drying furnace having a normal heat amount (Q com ) to the excess heat (Q res ) minus the heat supply (Q sup ) is fed into the drying furnace.

[0119] The control unit supplies the heat (Q sup ) is determined to be 83.93%, and the infrared heater output value is controlled to 20.983. In addition, the control unit determines the amount of heat supply (Q sup ) is determined to be 83.93%, and the infrared heater output value is controlled to 21.4. After that, the control unit determines the amount of heat supply (Q sup ) and infrared heater output value.

[0120] For four minutes after the electrodes are inserted, the amount of heat supplied to the drying oven is controlled using a differential heat supply method that increases the amount of heat supplied to the drying oven as time passes after the electrodes are inserted. As mentioned above, the infrared heater output value for each time interval in the drying control data is determined by the deviation between the electrode drying rate in the previous time interval and the target electrode drying rate. At this time, the target electrode drying rate is determined by the surplus heat (Q res ) is taken into consideration. Therefore, for four minutes after the electrodes are inserted, the electrode drying rate in the previous time interval did not reach the target electrode drying rate. This means that there is excess heat (Q res Therefore, the control unit may detect the excess heat (Q res ) remains, the heat supply method is differentiated to supply heat (Q sup ) to determine the immobility time (T imm The excess heat (Q res ) can suppress over-drying that occurs during the initial drying period, thereby preventing cracks in the electrodes.

[0121] On the other hand, the immobility time on the line (T imm After 5 minutes have passed since the electrodes were put into the drying furnace, which has a heat capacity of 10 ... res ) remains in the drying oven. At this time, the control unit controls the amount of heat supplied to the drying oven so that the amount of heat normally supplied to the drying oven is supplied. As described above, the infrared heater output value for each time interval in the drying control data maintains the infrared heater output value applied in the previous time interval if the electrode drying rate in the previous time interval reaches the target electrode drying rate. In this case, the target electrode drying rate is determined based on the surplus heat (Q res ) is taken into consideration. Therefore, after 5 minutes have passed since the electrodes were put in, the electrode drying rate in the previous time interval has reached the target electrode drying rate, which means that there is no excess heat (Q res Therefore, after 5 minutes, the control unit will start to supply heat (Q sup By determining the temperature at which the electrodes are heated and supplying a uniform amount of heat to the inside of the drying furnace, the quality uniformity of the electrodes can be improved.

[0122] The present invention uses the current immobility time (T imm ) conditions, and calculate the immobility time (T imm ) into a drying oven having a suitable amount of heat, the drying rate can be predicted, and the surplus heat (Q res ) can prevent excessive drying of the electrodes, thereby improving the quality of the electrodes.

[0123] Although the preferred embodiments of the present invention have been described above with reference to the drawings, a person skilled in the art or having ordinary knowledge in the art can understand that the present invention can be modified and changed in various ways without departing from the spirit and technical scope of the present invention as described in the claims.

[0124] Therefore, the technical scope of the present invention is not limited to the contents described in the Summary of the Invention of the specification, but is defined by the claims. [Explanation of symbols]

[0125] 10: Electrode 11: Electrode current collector 12: Electrode active material layer 100, 200: Electrode drying system 110: Drying oven 111, 211: First Drying Zone 112, 212: Second Drying Zone 113, 213: 3rd Dry Zone 114, 214: Hot air nozzle 115, 215: Heater 116, 216: Transport roller 117, 217: First operation control unit 118, 218: Second operation control unit 119, 219: Third operation control unit 120, 220: Data processing unit 130, 230: control unit 140, 240: Sensor section 250a, 250b: Measuring section

Claims

1. a drying oven for drying the electrodes; The immobility time (T ｉｍｍ The amount of excess heat (Q ｒｅｓ A data processing unit for calculating A control unit for controlling the amount of heat supplied to the drying oven, The control unit is a normal heat quantity (Q ｃｏｍ ) to the excess heat (Q ｒｅｓ ) minus the heat supply (Q ｓｕｐ ) into the drying furnace.

2. The drying control data is the immobility time (T ｉｍｍ ) and the amount of heat supplied (Q ｓｕｐ 2. The electrode drying system of claim 1, further comprising an electrode drying rate in response to the electrode drying rate.

3. The data processing unit includes: Among the previously calculated drying control data, the immobility time on the line (T ｉｍｍ ) extracting the drying control data having the closest immobility time to Based on the extracted drying control data, the normal heat amount (Q ｃｏｍ ) to the supply of heat (Q ｓｕｐ ) minus the surplus heat (Q ｒｅｓ 3. The electrode drying system of claim 2, further comprising:

4. The control unit determines whether or not there is a surplus heat (Q ｒｅｓ The amount of heat supplied while the remaining ｓｕｐ 2. The electrode drying system according to claim 1, wherein the temperature of the electrode is controlled so as to increase in a time series manner.

5. The control unit controls the amount of excess heat (Q ｒｅｓ ) in the drying oven, the normal heat quantity (Q ｃｏｍ 2. The electrode drying system of claim 1, wherein the supply of the first and second electrodes is controlled so that the first and second electrodes are supplied to the electrode drying system.

6. The electrode drying system according to claim 1 , wherein the drying furnace includes a hot air nozzle that supplies hot air to the electrodes to apply convection heat, and a heater that applies radiant heat to the electrodes.

7. 7. The electrode drying system according to claim 6, wherein the control unit controls the amount of heat supplied to the drying furnace by increasing or decreasing one or more of the following conditions: a temperature of the hot air sprayed from the hot air nozzle, a wind speed of the hot air, and an output of the heater.

8. The electrode drying system according to claim 7 , wherein the control unit controls the amount of heat supplied to the inside of the drying furnace uniformly throughout the entire drying furnace.

9. The electrode is not fed into the drying oven and the dead time (T ｉｍｍ 2. The electrode drying system of claim 1, further comprising a sensor unit that sends information to the data processing unit.

10. A measuring unit that collects information on the dryness of the electrode and transmits the collected information to the control unit, 2. The electrode drying system according to claim 1, wherein the control unit determines a dryness level of the electrode in accordance with dryness amount information received from the measurement unit, and corrects an increase or decrease in the amount of heat supplied to the drying furnace in real time.

11. The electrode drying system according to claim 10 , wherein the measurement unit collects one or more of a solid content of the electrode and a surface temperature of the electrode before and after passing through a drying oven.

12. (a) Immobility time (T ｉｍｍ ) collecting information; (b) The immobility time (T ｉｍｍ The amount of excess heat (Q ｒｅｓ ) (c) placing the electrode in a drying oven having a dead time; (d) controlling the amount of heat supplied to the drying oven; In step (d), the amount of heat (Q ｃｏｍ ) to the excess heat (Q ｒｅｓ ) minus the heat supply (Q ｓｕｐ ) is supplied into a drying furnace.

13. The drying control data is the immobility time (T ｉｍｍ ) and the amount of heat supplied (Q ｓｕｐ The electrode drying method according to claim 12, further comprising:

14. In step (b), the immobility time (T ｉｍｍ ) extracting the drying control data having the closest immobility time to Based on the extracted drying control data, the normal heat amount (Q ｃｏｍ ) to the supply of heat (Q ｓｕｐ ) minus the surplus heat (Q ｒｅｓ The electrode drying method according to claim 12, further comprising the steps of:

15. In step (d), excess heat (Q ｒｅｓ The amount of heat supplied while the remaining ｓｕｐ ) is controlled so as to increase over time, and excess heat (Q ｒｅｓ In the absence of the normal heat quantity (Q ｃｏｍ 13. The method for drying an electrode according to claim 12, wherein the supply of the liquid is controlled so that the liquid is heated to a temperature of 1000.degree.

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