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 this 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 are being proposed as a solution to address air pollution caused by existing gasoline and diesel vehicles that use fossil fuels. Therefore, the types of applications using secondary batteries are becoming increasingly diverse due to the advantages of secondary batteries, and secondary batteries are expected to be applied to more fields and products in the future.

[0004] These secondary batteries can be classified into lithium-ion batteries, lithium-ion polymer batteries, lithium polymer batteries, etc. depending on the configuration of the electrodes and electrolyte. Among these, lithium-ion polymer batteries are increasingly being used because they are less likely to leak electrolyte and are easier to manufacture. Generally, 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-shaped case made 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 interposed between the positive and negative electrodes. The electrode assembly is classified into a jelly roll type, in which a long sheet-like positive electrode and a negative electrode coated with an active material are wound up with a separator interposed between them, and a stack type, in which a number of positive electrodes and a negative electrodes of a predetermined size are stacked sequentially 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 deviation in dryness in the width direction of the electrode during drying and the control of the drying completion time.

[0007] Meanwhile, electrodes coated with electrode slurry undergo 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 excess heat accumulates inside the drying oven during the idle time when the electrodes are not loaded into the drying oven in the drying section. If the electrodes are loaded into the drying oven in this state, the excessive heat accumulated inside the drying oven may cause cracks or wrinkles in the electrodes in the initial drying section.

[0008] In particular, electrode cracks caused by excessive drying in the initial drying section generate electrode powder, which scatters far away along the hot air convection in the drying furnace, contaminating surrounding electrodes and reducing the quality of the electrodes. Therefore, it is very important to prevent excessive drying 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 intended to solve the above-mentioned problems, and provides an electrode drying system and an electrode drying method that, in a process of drying electrodes having a standstill time, suppresses the phenomenon in which electrodes placed in a drying oven having a standstill time are over-dried during the initial drying process due to excess heat accumulated in the drying oven, thereby preventing cracks in the electrodes. [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 excess heat (Q res , Residual Quantity of Heat), and a control unit that controls the amount of heat supplied to the drying oven, and the control unit calculates the normal amount of heat (Q com , Common Quantity of Heat) to Excess Heat (Q res ) minus the supplied heat (Q sup , Supply Quantity of Heat) into the drying furnace.

[0012] In a specific example, the dryer control data is the idle 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 the immobility time (T imm ) is extracted, and the normal heat quantity (Q com ) to supply heat (Q sup ) minus the excess heat (Q res ) is calculated.

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

[0015] In addition, the control unit calculates the amount of excess heat (Q res ) in the drying oven, 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 temperature of the hot air sprayed from the hot air nozzle, the 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 unit that sends information to a data processing unit.

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

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

[0022] The present invention also provides an electrode drying method using the electrode drying system described above. 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 drying control data. imm The 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 step (d) is performed by calculating the normal amount of heat (Q com , Common Quantity of Heat) to Excess Heat (Q res ) minus the supplied heat (Q sup , Supply Quantity of Heat) into the drying furnace.

[0023] In a specific example, the dryer control data is the idle 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 excess heat (Q res ) is calculated.

[0025] In another specific example, in step (d), the excess heat (Q res ) remains, the amount of heat supplied (Q sup ) is controlled so that it increases over time, and excess heat (Q res ) in the drying oven, the normal heat amount (Q com ) is supplied. [Effects 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 standstill time, and a lower amount of heat than normally supplied is supplied during the initial drying time to prevent the electrodes from being over-dried due to excess heat, thereby preventing cracks from occurring in the electrodes and suppressing contamination inside the drying furnace. Furthermore, 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 pre-calculated drying data. [Brief explanation of the drawings]

[0027] [Figure 1] 1 is a block diagram showing the configuration of an electrode drying system according to an embodiment of the present invention. [Figure 2] 1 is a schematic diagram illustrating the structure of an electrode drying system according to an embodiment of the present invention. [Figure 3] FIG. 10 is a block diagram showing the configuration of an electrode drying system according to another embodiment of the present invention. [Figure 4] FIG. 10 is a schematic diagram showing the structure of an electrode drying system according to another embodiment of the present invention. [Figure 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 INVENTION

[0028] Because the present invention can be modified in various ways and can take various forms, specific embodiments are illustrated in the drawings and described in detail herein, but it is not intended to limit the invention to the specific disclosed forms, and it is understood that the invention includes all modifications, equivalents, and alternatives falling within the spirit and technical scope of the invention.

[0029] In this application, terms such as "comprise" and "have" are intended to specify the presence of a feature, numeral, step, operation, component, part, or combination thereof described in the specification, but may be understood as not excluding the presence or addition of one or more other features, numerals, steps, operations, components, parts, or combinations thereof. Furthermore, when a layer, film, region, plate, or other part 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 between them. Conversely, when a layer, film, region, plate, or other part 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 between them. Furthermore, in this application, "over" can include not only the case where it is "on top" but also the case where it is "under" the other part.

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

[0031] Generally, electrodes coated with electrode slurry undergo a drying process while traveling through a drying section in a continuous process. However, there may be a time gap between the electrode slurry coating process and the drying process for various reasons. During the idle time in the drying section when the electrodes are not loaded into the drying oven, excess heat accumulates inside the drying oven. If the electrodes are loaded into the drying oven in this state, the excessive heat accumulated inside the drying oven may cause cracks or wrinkles in the electrodes in the initial drying section. In particular, electrode cracks caused by over-drying in the initial drying section can produce electrode powder, which can then be dispersed far away by hot air convection in the drying oven, contaminating surrounding electrodes and reducing the quality of the electrodes. Therefore, it is very important to prevent over-drying in the initial drying section of the electrodes.

[0032] Therefore, in the present invention, in a drying process of electrodes having a standstill time, in order to prevent the phenomenon that electrodes placed in a drying oven having a standstill time are overdried during the initial drying period due to excess heat accumulated in the drying oven, a heat amount that is temporarily reduced from the heat amount normally supplied to the drying oven during the initial drying period immediately after the electrodes are placed in the drying oven having a standstill time is supplied, and the heat amount is supplied with time-series differences. Furthermore, drying control data having conditions that are closest to the standstill time conditions on the line are derived from pre-calculated drying control data, and the excess heat amount inside the drying oven during the standstill time is calculated from the derived drying control data. Then, the heat supply amount is calculated by subtracting the excess heat amount from the heat amount normally supplied via the control unit, and the supplied heat amount is supplied to the drying oven. In this way, the heat supply amount supplied to the drying oven during the initial drying period is a heat amount that is reduced from the heat amount normally supplied, but is calculated taking into account the excess heat remaining in the drying oven.

[0033] The present invention is characterized in that, during the initial drying time after the electrodes are placed in the drying oven, which has 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 and controlled based on the drying control data under the conditions that best match the current conditions from among the data obtained in advance, and the amount of heat supplied into the drying oven can be determined automatically using a data processing unit and a control unit.

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

[0035] FIG. 1 is a block diagram showing the configuration of an electrode drying system according to one embodiment of the present invention. FIG. 2 is a schematic diagram showing the structure of an electrode drying system according to one embodiment of the present invention. Referring to FIGS. 1 and 2, an electrode drying system 100 according to the present invention can be divided into a plurality of drying zones 111, 112, 113 along the x-axis, which is the direction in which the electrode 10 is transported, and includes a drying oven 110 for drying the electrode 10 and a dead time (T immThe excess heat (Q res The control unit 130 includes a data processing unit 120 that calculates the residual quantity of heat (Q ), and a control unit 130 that controls the quantity of heat supplied to the drying furnace 110. com , Common Quantity of Heat) to Excess Heat (Q res ) minus the supplied heat (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 ) can be specifically 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, normal heat (Q com ) is the immobility time (T imm ) means the amount of heat normally supplied to the drying oven 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 nozzle 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, and 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-mentioned immobility time (T imm ) and 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 ) 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 excess heat (Q res When the electrode 10 is placed in the drying furnace 110 in which excess heat (Q res ) may cause excessive drying of the electrode 10, which may induce cracks in the electrode 10. Therefore, such a dead time (T 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 suitably 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 ) when there is excess heat (Q res ) to prevent cracks from occurring in the electrode 10. The control unit 130 of the present invention controls the dead 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, 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 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 excess heat (Q res ) is calculated. Here, the immobility time on the line (T imm ) is the immobility time (T imm ) means

[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 The output value of the heat source may be a temperature value of the hot air, a wind speed value of the hot air, an output value of the heater, etc.

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

[0046] Specifically, the drying control data is calculated based on 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 will be explained in detail below.

[0047] To explain this in detail using one 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 placed in the drying furnace 110 having the heating element 110a, is divided into n (n≧2) time intervals in a time series, and the amount of heat (Q) supplied to the drying furnace 110 in each time interval T1, T2, T3, ... Tn is sup ) are 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, excess heat (Q res ) remain in the drying furnace 110. res ) remains in the time intervals T6, T7...T10. sup )Q1 is usually the amount of heat (Q com ) is reduced from (Q com >Q1), and the amount of heat supplied in T2, which is a time interval after the first time interval T1 (Q sup ) Q2 has a slightly 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, and their values ​​(Q com >Q5>Q4>Q3>Q2>Q1). imm ) in the drying furnace 110 having excess heat (Q res ) when there is a normal amount of heat (Q com) and gradually / stepwise increasing the amount of heat supplied over time, thereby preventing the electrode 10 from initially becoming over-dried.

[0049] On the other hand, excess heat (Q res The heat quantity in the time intervals T6, T7...T10 where no heat remains is Q com The relationship between Q6, Q7, Q8, Q9, and Q10 can be established. This means that there is 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 the drying control data. That is, the drying control data is the residual heat quantity (Q res ) and supply heat (Q sup ) is determined.

[0050] To explain this in more detail using 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 the preset target electrode dryness rate is assumed to be Y5. Then, the heat quantity in each time interval T1, T2, ... T5 is 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 in which the electrode dryness rate is 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 expected behavior, in the time interval before the time interval in which the electrode dryness rate is closest to the target electrode dryness rate, the normal heat amount (Q com ) with less heat supply (Q sup ) is determined, and in the subsequent time interval, the normal heat quantity (Q com ) with the same amount of heat as the supplied heat (Q sup ) can be determined.

[0051] FIG. 5 shows the amount of heat supplied (Q sup ) is a schematic diagram showing the relationship with the electrode dryness rate for determining the temperature.

[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. When the output value of the infrared heater is increased, the amount of heat supplied (Q sup ) increases, and conversely, when the output value of the infrared heater is reduced, 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. Proportional control (P control) refers to controlling the manipulated variable in proportion to the difference between the target value and the 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 supplied (or the infrared heater output value) in the previous time interval and the amount of heat supplied (or the infrared heater output value) 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, the amount of heat supplied (or the infrared heater output value) in the specific time interval exhibits a relatively large variation compared to the amount of heat supplied (or the infrared heater output value) in the previous time interval. Conversely, when the deviation between the electrode drying rate in the specific time interval and the target electrode drying rate is relatively small, the amount of heat supplied (or the infrared heater output value) in the specific time interval exhibits a relatively small variation compared to the amount of heat supplied (or the infrared heater output value) in the previous time interval. This behavior allows for fine adjustment of the electrode dryness rate as the fluctuation in the amount of heat supplied (or infrared heater output value) in a specific time interval decreases as the electrode dryness rate in the previous time interval reaches the target electrode dryness rate (proportional control).

[0054] However, if the electrode dryness rate in the previous time interval is equal to or exceeds the target electrode dryness rate (over-dried), 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, but is determined to be the same as the electrode dryness rate 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 over-dried and to supply a constant amount of heat to the drying oven, thereby improving the uniformity of electrode quality.

[0055] In addition, if the electrode drying rate in the previous time interval 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 ) remains in the drying furnace 110. Generally, the target electrode drying rate is determined by the 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 (T imm ) is the closest immobility time (T imm ) to extract the drying control data. If necessary, the data processing unit 120 may extract the immobility time (T imm ) conditions, immobility time (T imm Before the electrode is placed in the drying oven having the infrared heater, the infrared heater operating time and output value, the product model name of the electrode 10, and the indoor temperature according to the season can be extracted. That is, from the pre-calculated drying control data, the immobility time on the line (T imm ) is the closest immobility time (T imm) and at the same time, drying control data having the same operating time and output value of the infrared heater on the line can be extracted. Alternatively, the immobility time (T imm ) is the closest immobility time (T imm ) and at the same time, it is possible to extract drying control data that matches the operating time of the infrared heater on the line and the product model name of the electrode.

[0057] At this time, the data processing unit 120 calculates the immobility time (T imm ) coincides with the immobility time (T imm ) information. The search grid is a machine learning model in which desired conditions are used as parameters, and various combinations of parameters are tried to find the optimal parameters. In this invention, the parameters are immobility time (T imm ) can be used as a parameter for the immobility time (T 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 depending on the season, until the electrode is placed in the drying oven having the drying oven.

[0058] Furthermore, 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 excess 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 supplied heat (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 determining the immobility time (T imm ) and 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 heat supply quantity (Q sup ) is the amount of heat supplied (Q sup ) and the amount of heat supplied (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 supplied to the drying oven 110 on the line (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

[0061] Furthermore, the control unit 130 controls the amount of excess heat (Q res ) remains, the amount of heat supplied (Q sup ) is controlled so as to increase over time. res ) is not required, the drying furnace 110 is normally supplied with heat (Q com ) is supplied to the drying furnace 110. res ) remains, the amount of heat (Q com ) to the excess heat (Q res ) minus the supplied heat (Q sup ) is supplied to the drying furnace 110, but the excess heat (Q res ) depending on the degree of heat supply (Q sup ) is determined. Generally, the immobility time (T immThe electrode 10 is placed in a drying furnace 110 having a temperature of 1000 K. After a certain time has passed, the excess heat (Q res ) will decrease, the control unit 130 controls the amount of heat supplied to the drying furnace 110 (Q sup ) gradually increases. Meanwhile, the amount of excess heat (Q res ) is not usually used, 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, and the amount of heat supplied to the drying oven 110 is controlled uniformly throughout the entire drying oven 110. imm ), the excess heat (Q res ) is accumulated, so the excess heat (Q res ) is preferably controlled 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 chamber-shaped, provides a space for the electrode 10 to be dried to move inside the drying oven 110, and prevents internal heat from escaping to the outside during drying.

[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 current collector. The electrode slurry may be coated on at least one surface of the current 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 formed 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 and does not induce chemical changes in the battery. For example, stainless steel, aluminum, nickel, titanium, calcined 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 strength of the positive electrode active material, and may be in various forms such as a film, sheet, foil, net, porous material, foam, or nonwoven fabric.

[0068] A negative electrode current collector sheet is generally formed 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. Examples of such a negative electrode current collector include copper, stainless steel, aluminum, nickel, titanium, calcined carbon, copper or stainless steel surface-treated with carbon, nickel, titanium, silver, and the like, and aluminum-cadmium alloys. Similarly to the positive electrode current collector, the surface may be formed with fine irregularities to strengthen the binding strength of the negative electrode active material, and the negative electrode current collector may be used in various forms, such as a film, sheet, foil, net, porous material, foam, or nonwoven fabric.

[0069] In the present invention, the positive electrode active material is a substance 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; lithium manganese oxide substituted with one or more transition metals; 1-y M yLithium nickel-based oxide represented by LiO2 (wherein M=Co, Mn, Al, Cu, Fe, Mg, B, Cr, Zn, or Ga, and contains one or more elements among 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, A=F, P or Cl) lithium nickel cobalt manganese composite oxide; 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, and 0≦z≦0.1), but are not limited thereto.

[0070] The negative electrode active material may be, 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 z(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) and other metal composite oxides; lithium metal; lithium alloys; silicon-based alloys; tin-based alloys; 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. can 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 chemical changes 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 can 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, polyvinyl pyrrolidone, tetrafluoroethylene, polyethylene, polypropylene, ethylene-propylene-diene terpolymer (EPDM), sulfonated EPDM, styrene-butadiene rubber, fluorine rubber, various copolymers, etc.

[0073] The electrode slurry can be prepared by dissolving the electrode active material, conductive material, binder, and the like in a solvent. The solvent is not particularly limited as long as it can disperse the electrode active material and the like, and either an aqueous or non-aqueous solvent can be used. For example, the solvent can 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 can 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, taking into account 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, as drying means for drying the electrode 10, 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. Referring to FIG. 2, the hot air nozzles 114 and heaters 115 may be arranged at regular intervals along the direction of movement of the electrode 10 (MD direction, x direction), and apply hot air or radiant heat in a direction perpendicular to the electrode 10. In FIG. 2, the hot air nozzle 114 and infrared heater are shown as being located above the electrode 10, i.e., on the underside of the ceiling of the drying oven 110. However, if the electrode active material layer 12 is formed on both sides of the current collector, the hot air nozzle 114 and heater 115 may be located above and below the electrode 10, respectively. Furthermore, although 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, 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 fixes the hot air nozzle 114 to the ceiling of the drying oven 110. The main body is hollow and transfers hot air transferred 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 through which the hot air is ejected is formed on the bottom surface of the ejection part. The ejection port may have a structure in which a plurality of pores are arranged at regular intervals.

[0075] Meanwhile, in a specific example of the present invention, the heater 115 may be an infrared heater, which may include an infrared heater that irradiates the electrode 10 with infrared rays 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 direction of movement 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, and an ordinary engineer 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 oven 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] The drying oven 110 may include one or more transfer rollers 116 for transferring the electrode 10. A plurality of the transfer rollers 116 may be arranged at regular intervals along the transfer direction of the electrode 10, support the electrode 10 during the drying process, and transfer the electrode 10 after drying to the outside of the drying oven 110. The rotation speed of the transfer rollers 116 may also be controlled to control the amount of drying of the electrode 10.

[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 determines 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 the entrance of the drying oven 110 where the electrode 10 is inserted. The sensor unit 140 includes a sensor that detects the movement of the electrode 10, and the type of the sensor is not limited as long as it can detect whether the electrode 10 has been inserted. Therefore, the sensor may be a type that detects weight or an image camera.

[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 idle time (T immThe 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. As a result, the operation control units 117, 118, and 119 of the drying oven 110 control the instructed supply heat amount (Q sup ) The amount of heat supplied is controlled in accordance with 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. Referring to Figs. 3 and 4, the electrode drying system 200 of the present invention comprises a drying oven for drying the electrode 10, and a dead time (T imm The 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 supplied heat (Q sup ) into the drying oven. Furthermore, it is characterized in that the electrode 10 is not fed into the drying oven and the dead time (T imm The drying oven 210 further includes a sensor unit 240 that transmits information about the dryness of the electrode 10 to the data processing unit 220, and a measurement unit that collects information about the dryness of the electrode 10 and transmits the collected information to the control unit 230. The control unit 230 determines the dryness level of the electrode 10 according to the dryness 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 instruct 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 the 1000-kJ / s, the excess heat (Q res ) remains, while the amount of heat (Q com ) to prevent over-drying in the initial stage, while supplying a reduced amount of heat (Q res ) no longer remains, the dryness of the electrode 10 can be corrected in accordance with the dryness level of the electrode 10, thereby achieving a uniform dryness level of the electrode 10. That is, the measuring units 250; 250a, 250b collect dryness information of the electrode 10 in real time, and the control unit 230 determines the dryness level of the electrode 10 based on the collected dryness information, and periodically corrects the dryness in accordance with the dryness level of the electrode 10, thereby achieving the effect of uniformly controlling the dryness level of the electrode 10.

[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 that measures the loading amount of the electrode 10 and a temperature measuring device 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. The measuring units 250a and 250b may be installed at the inlet and outlet of the drying oven, respectively, and may 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 using a pre-entered calculation formula. 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 determining the dryness level of the electrode 10.

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

[0087] In order for the control unit 230 to correct the dryness of the electrode 10 in real time, the measurement units 250a and 250b are configured to periodically collect dryness 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 information from the measurement units 250a and 250b, and periodically controls the amount of heat supplied to the drying oven.

[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 pre- and post-drying loading amount and / or electrode surface temperature of the electrode 10, from the measurement units 250a and 250b, and may also receive a reference value that determines whether the drying level of the electrode 10 is over-dried or under-dried. The control unit 230 then compares the drying amount information with the reference value to determine whether the drying level of the electrode 10 is over-dried, under-dried, or normally dried. The control unit 230 then compares the drying amount information with the reference value to quantitatively determine the degree of over-drying or under-drying and determines a method for controlling the drying intensity. Once the drying level and drying amount of the electrode 10 have been determined, the control unit 230 may adjust 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 that transports the electrode 10, 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 preferably 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 configured to periodically collect dryness weight 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 the dryness weight information for 1 to 5 minutes immediately before the time when the control unit 230 is scheduled to control the drying intensity. That is, the measuring units 250a and 250b do not collect the dryness weight information of the electrode 10 immediately after the control unit 230 controls the drying intensity of the drying oven, but collect the dryness weight information of the electrode 10 after a certain time has passed since the control unit 230 started controlling the drying intensity. This is because a certain time is required for the dryness weight correction effect caused by changing the drying intensity of the drying oven to appear.

[0091] The measuring units 250a and 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] Furthermore, 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 inside the drying oven can be controlled more precisely.

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

[0094] FIG. 6 is a flowchart showing the steps 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) immobility time (T imm(b) collecting immobility time (T ) information from pre-calculated drying control data. imm The 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 step (d) is usually com , Common Quantity of Heat) to Excess Heat (Q res ) minus the supplied heat (Q sup , Supply Quantity of Heat) is supplied into 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. 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 ) is the closest immobility time (T imm ) and calculate the normal heat quantity (Q com ) to supply heat (Q sup ) minus the excess 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 ) and extracts the drying control data having the condition closest to the current condition, and calculates the immobility time (T imm The excess heat (Q) remaining in the drying furnace for a certain period of time before the electrodes are placed in the drying furnace res) is calculated. Then, when the initial drying time is divided into multiple time intervals in a chronological order, the surplus heat (Q res ) is calculated. The excess heat (Q res ) is sent to the control unit.

[0098] In the above step (d), the excess heat (Q res ) is the immobility time on the line (T imm The predicted excess heat (Q) remaining inside the drying furnace during the initial drying time after the electrode is placed in the drying furnace res Therefore, the control unit usually uses the amount of heat (Q com ) to the excess heat (Q res ) minus the supplied heat (Q sup ) is fed into the drying furnace.

[0099] The above step (d) is to generate excess heat (Q res ) while remaining, the amount of heat supplied (Q sup ) is controlled so that it increases over time, and excess heat (Q res ) is not required for the drying oven. com ) is supplied to the drying oven. res ) remains, while the amount of heat (Q com ) and the surplus heat (Q res ) and consider the amount of heat supplied (Q sup ) is supplied so that the amount of heat increases gradually / step by step. On the other hand, the excess heat (Q res ) is not usually used, com ) is supplied to the drying furnace with the same amount of heat as

[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, and shows the immobility time (T imm After inserting the electrode into the drying oven, the output value of the infrared heater that supplies heat to the drying oven in each time interval during the initial drying time and the supplied heat amount (Q sup ) shows the electrode drying rate according to the

[0103] [Table 1]

[0104] Referring to Table 1 above, the immobility time (T imm ) means the time when the electrode is not dried in the drying oven or the electrode is not put into the drying oven. imm ) (where, sequence "0" means that no electrode is placed in the drying oven, and sequence "1" means that an electrode is placed in the drying oven). The infrared heater output value means the intensity value of the output at which the infrared heater emits heat energy. Here, the output value ranges from 0 to 25. The first to fourth heaters 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 to this. The supplied heat quantity (Q sup ) is the percentage of the infrared heater output value in the corresponding order relative to the maximum output value of the infrared heater, and the excess heat (Q res ) is usually expressed as the amount of 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 can be determined based on the deviation between the electrode dryness rate in the previous sequence and the target electrode dryness rate. The process of deriving the output value of the infrared heater in the current sequence will be described in detail with reference to Tables 2 and 3 below.

[0106] Table 2 below explains a proportional control (P control) method that 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 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 refers to the maximum electrode dryness rate set as the limit for the electrode model to be dried. The maximum electrode dryness rate is the standard 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 this determines the infrared heater output value (86.7%) to be applied in the current sequence.

[0109] In number 2, the output 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 the infrared heater output value (85%) to be applied in the current sequence is determined accordingly. In number 2, the deviation between the electrode dryness rate in the previous sequence and the target electrode dryness rate is smaller than in number 1. Therefore, it can be observed that in number 2, the infrared heater output value applied in the current sequence shows a smaller variation amount compared to the infrared heater output value applied in the previous sequence than in 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 the infrared heater output value (82.9%) to be applied in the current order is determined accordingly. In number 3, it can be observed that the infrared heater output value applied in the current order from number 2 shows a smaller range of change compared to the infrared heater output value applied in the previous order.

[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 equal to 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 (85%) in the previous step 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 step is determined to be the same as the infrared heater output value applied in the previous step. Since increasing the infrared heater output value applied in the current step could cause the electrodes to become overly dry, the infrared heater output value applied in the previous step is maintained. In case 2, the electrode dryness rate (86%) in the previous step exceeds the target electrode dryness rate (85%). That is, this corresponds to the case where the electrodes are overly dried in the previous step. In this case, as in case 1, the infrared heater output value applied in the current step is determined to be the same as the infrared heater output value applied in the previous step.

[0114] Referring again to Table 1, the dead time (T imm) is 154 minutes, the data processing unit selects the immobility time (T imm The pre-calculated drying control data is derived using a search grid method when the immobility time (T imm In the embodiment, the pre-calculated drying control data is not derived when the immobility time (T imm ) information was used as a variable, but it is not limited to this. imm ) information, 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 drying rate, and the 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 performed by directly reflecting the information or by carrying out a correction process as necessary.

[0116] The following description will be given on the assumption that the data processing unit determines that the correction process is unnecessary.

[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 calculates 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 placed in the drying furnace having a normal heat amount (Q com ) to the excess heat (Q res ) minus the supplied heat (Q sup ) is fed into the drying furnace.

[0119] The control unit controls the amount of heat supplied (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 supplied (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 excess 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 does not reach the target electrode drying rate. This means that there is excess heat (Q res Therefore, the control unit determines whether the excess heat (Q res ) remains, and the heat supply method is set with a difference, etc., to supply heat (Q sup ) to determine the immobility time (T imm The excess heat (Q res ) can suppress excessive 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 placed in the drying furnace, excess heat (Q res ) does not remain. In this case, 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 also determined by the excess heat (Q res 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 excess heat (Q res Therefore, after 5 minutes have passed, the control unit will start supplying the normal heat amount (Q sup ) and supplying a uniform amount of heat to the drying furnace can improve the uniformity of electrode quality.

[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 excess heat (Q res ) can prevent excessive drying of the electrode, thereby improving the quality of the electrode.

[0123] Although the preferred embodiments of the present invention have been described above with reference to the drawings, it will be understood that a person skilled in the art or an individual having ordinary knowledge in the art can make various modifications and changes to the present invention without departing from the spirit and technical scope of the present invention as set forth in the claims.

[0124] Therefore, the technical scope of the present invention is not limited to the content 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: Third Drying Zone 114, 214: Hot air nozzle 115, 215: heater 116, 216: Transfer 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 excess heat (Q ｒｅｓ a data processing unit for calculating a control unit that controls the amount of heat supplied to the drying oven, The control unit is configured to control the normal heat quantity (Q ｃｏｍ ) to the excess heat (Q ｒｅｓ ) minus the supplied heat (Q ｓｕｐ ) into the drying furnace.

2. The control unit controls the amount of excess heat (Q ｒｅｓ ) while remaining heat supply (Q ｓｕｐ 2. The electrode drying system according to claim 1, wherein the temperature is controlled so that the temperature increases over time.

3. The control unit controls the amount of excess heat (Q ｒｅｓ ) in the drying oven, the normal heat amount (Q ｃｏｍ 2. The electrode drying system according to claim 1, wherein the supply of the electrode drying liquid is controlled so that the supply of the electrode drying liquid is sufficient.

4. 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.

5. 5. The electrode drying system according to claim 4, wherein the control unit controls the amount of heat supplied into the drying furnace by increasing or decreasing one or more conditions of 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.

6. The electrode drying system according to claim 5 , wherein the control unit controls the amount of heat supplied to the entire drying furnace so as to be uniform within the drying furnace.

7. The electrode is not fed into the drying oven and the dead time (T ｉｍｍ 10. The electrode drying system of claim 1, further comprising a sensor unit that sends information to the data processing unit.

8. Further comprising a measuring unit that collects information on the dryness of the electrode and sends 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 the 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.

9. The electrode drying system according to claim 8 , 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.

10. (a) Immobility time (T ｉｍｍ ) collecting information; (b) The immobility time (T ｉｍｍ The excess heat (Q ｒｅｓ ) and (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 supplied heat (Q ｓｕｐ ) into a drying furnace.

11. In step (d), excess heat (Q ｒｅｓ ) while remaining heat supply (Q ｓｕｐ ) is controlled so as to increase over time, and excess heat (Q ｒｅｓ ) is not required, the drying oven is normally supplied with heat (Q ｃｏｍ 11. The electrode drying method according to claim 10, wherein the supply of the water is controlled so that the water is supplied to the electrode.

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