JP5233248B2 - Electrode manufacturing equipment - Google Patents

Description

  The present invention relates to an electrode manufacturing apparatus for manufacturing a strip electrode of a secondary battery, and more particularly to an electrode manufacturing apparatus having a drying furnace for drying a strip electrode that is continuously conveyed.

  Conventionally, in order to extend the life of a charge / discharge cycle or to obtain a high energy density, an increase in the area of a thin film of an electrode plate of a secondary battery such as a lithium ion battery has been attempted. In order to realize an increase in the area of the thin film, a long strip, that is, a strip electrode is often used for the electrode plate. As such a strip electrode, for example, a positive electrode active material powder is added with a conductive agent and a binder and dispersed in a suitable solvent, and a liquid active material coating solution is applied to form a coating material that becomes an active material layer. A positive electrode plate obtained by forming a film on a strip-shaped electrode substrate is disclosed (for example, see Patent Documents 1 and 2).

  Such a positive electrode plate is manufactured through a coating process, a drying process, and a winding process. In the coating step, the coating liquid is applied onto a strip-shaped electrode substrate. In the drying step, the electrode substrate coated with the coating liquid is carried into a drying furnace and dried. In the drying furnace, heated gas (hot air) is sprayed on the coating solution applied on the electrode substrate. With this hot air, the moisture contained in the coating solution is evaporated and dried, whereby a coating film is formed on the electrode substrate. After the drying process, the positive electrode plate is unloaded from the drying furnace and wound up in the winding process.

  Of the above three steps, the drying step is a very important step. If the dried state of the strip electrode is insufficient, or if the dried state of the strip electrode during the drying process is too strong, the quality of the secondary battery will be significantly lowered.

  For example, if the coating solution is rapidly dried at the optimal speed, the temperature in the drying oven exceeding the optimal air flow, and the air flow, the binder will float on the surface of the coating film together with the solvent, and the coating film after drying will The binding agent is unevenly distributed on the surface, and the binding property of the portion where the binding agent is diluted in the coating film and the binding property between the coating film and the electrode substrate are lowered. For this reason, the coating film may be peeled off from the base material during the pressure forming of the coating film, or the coating film may be peeled off, dropped off, cracked, etc. during the subsequent battery assembly process and charge / discharge. In terms of battery characteristics, the discharge capacity is reduced due to overvoltage due to the uneven distribution of the binder in the coating film, or the discharge capacity is deteriorated due to insufficient binding force. Therefore, in the drying process, the coating speed, drying temperature, and drying air volume are optimized according to the coating amount of the coating solution, and the coating solution is dried without reducing the binding properties of the coating film. It is necessary to let

Thus, in the drying process, it is very important in terms of quality to grasp the dry state (water content) of the coating film on the strip electrode. The dry state of the coating film is greatly influenced by the absolute humidity of the hot air as well as the temperature and air volume in the drying furnace. Therefore, the temperature, humidity, etc. of the heated heating air (air supply) are measured, and the temperature, air volume, humidity, etc. of the exhaust air (exhaust) are measured, and the amount of moisture contained in the coating film based on the results. Has been disclosed (see, for example, Patent Document 3).
JP 63-10456 A JP-A-3-285262 JP-A-5-50023

  In the control technique described in Patent Document 3, a humidity sensor for measuring the amount of evaporated water from the strip electrode is installed in the exhaust duct. In this case, a time delay that cannot be ignored occurs in the measurement of the amount of evaporated water, and accurate humidity control becomes difficult. In this case, since it is not clear what path the gas in the exhaust duct has taken, there is no guarantee that the measured value of the hygrometer will indicate the amount of moisture evaporated from the strip electrode. For example, water vapor once evaporated from the coating film may collide with the coating film again. In this case, the difference between the humidity measured by the hygrometer in the exhaust duct and the amount of evaporated water from the strip electrode is large. Become.

  In addition, since the humidity sensor in the exhaust duct can only measure the average humidity (average of a certain range on the strip electrode) in the drying furnace, it cannot grasp the dry state of each part of the strip electrode. Therefore, it is difficult to control the drying state so as to reduce the drying unevenness of the strip electrode.

  The present invention has been made to solve the above problems, and provides an electrode manufacturing apparatus capable of accurately grasping the dry state of individual portions of a strip electrode without delay in a drying furnace. It is intended.

  An electrode manufacturing apparatus according to the present invention is an electrode manufacturing apparatus having a drying furnace that dries a strip-shaped electrode that is continuously transported, and is generated in a gas blown to the strip-shaped electrode that is transported in the drying furnace. A gas intake pipe having an opening disposed in the boundary layer; and a water content measurement sensor for measuring a water content of the gas taken in via the gas intake pipe.

  Moreover, in the said gas intake tube, the said opening part can be installed so that it may open in the reverse direction to the conveyance direction of the said electrode base material.

  Further, the gas intake pipe in which the opening is disposed in the vicinity of the carry-in port of the transfer furnace, the gas intake pipe in which the opening is disposed in the vicinity of the carry-out port of the transfer furnace, the carry-in inlet and the carry-in The gas intake pipe in which the opening is disposed at an intermediate portion with respect to the outlet, and the moisture amount measurement sensor provided for each gas intake pipe may be provided.

  In addition, the length of the gas intake pipe can be set to be substantially equal.

  Further, the belt-like electrode transported in the first half from the carry-in port to the intermediate part is a physical quantity related to the gas blown to the belt-like electrode in the first half so as to be gently dried, and the belt-like electrode Adjusting the physical quantity that affects the amount of evaporated water from, and the strip electrode transported in the latter half part from the intermediate part to the carry-out port, so that the dry state is stronger than in the first half part, An adjusting device for adjusting the physical quantity in the second half can be further provided.

  Here, the physical quantity related to the gas blown to the strip electrode, and the physical quantity that affects the amount of evaporated water from the strip electrode is, for example, the temperature or flow velocity of the gas blown to the strip electrode, If the physical quantity is changed, the quantity expresses a physical property and state in which the amount of evaporated water of the strip electrode changes.

  Further, the adjusting device has a table showing a relationship between a measured value of the amount of water contained in the gas taken in through the gas intake pipe and the amount of water contained in the strip electrode, and the strip The physical quantity can be adjusted so that the amount of water contained in the vicinity of the carry-out port of the electrode is within an allowable value.

  According to the present invention, since the opening of the gas intake tube is provided in the boundary layer that is blown to the strip electrode and is generated in the gas, the gas intake tube is brought together with the strip electrode by friction with the surface of the strip electrode. The moving gas, that is, the gas containing the amount of water evaporated from the surface of the belt-like electrode can be taken in as it is. The moisture measurement sensor measures the amount of moisture contained in the gas taken in through this gas intake tube, so it can accurately measure the amount of evaporated water from each part of the strip electrode without delay. become able to.

  Hereinafter, an electrode manufacturing apparatus according to an embodiment of the present invention will be described in detail with reference to the drawings. The electrode manufacturing apparatus according to the present embodiment is an apparatus for manufacturing a strip electrode of a lithium ion battery. FIG. 1 shows a schematic configuration of an electrode manufacturing apparatus 1. As shown in FIG. 1, the electrode manufacturing apparatus 1 includes a coating device 11, a drying furnace 12, a winding device 13, and a centralized management device 14 as an adjusting device.

  The coating device 11 applies a coating solution 29 to the electrode base material 27. Here, as the electrode base material 27, for example, an aluminum foil or a copper foil is used. Moreover, as the coating liquid 29, for example, a positive electrode active material (electrode main material) such as lithium cobalt oxide, a conductive agent such as acetylene black, a binder such as polytetrafluoroethylene, and the like are dissolved in water. Is used. The coating liquid 29 is supplied to the nozzle 31 by a pump (not shown), and is applied onto the electrode substrate 27 from the nozzle 31. The electrode base material 27 to which the coating liquid 29 has been applied, that is, the belt-like electrode P, is conveyed to a carry-in port provided at the −Y end of the drying furnace 12 and is carried into the drying furnace 12.

  The strip electrode carried into the drying furnace 12 is conveyed in the furnace at a predetermined speed V by L [m] (for example, L = 30 m) in the + Y direction, and from a carry-out port provided at the + Y end of the drying furnace 12. It is carried out. A plurality of nozzles 20 are provided above and below the belt-like electrode P transported in the furnace at a predetermined interval (for example, at an interval of about 30 cm) in parallel with the belt-like electrode P being transported (that is, along the Y-axis direction). It is arranged. The gas (heated and dried hot air) injected from the nozzle 20 is blown to the strip electrode P from the time when it is carried into the drying furnace 12 until it is carried out.

  The winding device 13 winds the strip electrode P carried out from the carry-out port of the drying furnace 12. The central management device 14 controls the operations of the coating device 11, the drying furnace 12, and the winding device 13. The centralized management device 14 mainly manages the dry state of the strip electrode P in the drying furnace 12.

  FIG. 2 schematically shows the flow of the airflow in the drying furnace 12. As shown in FIG. 2, the nozzle 20 in the drying furnace 12 is connected to an air supply duct 26, and a heater 25 is connected to the air supply duct 26. The heater 25 is connected to the central management device 14, and the temperature is controlled by the central management device 14. The heater 25 heats air sent by a fan (not shown) in accordance with a temperature command sent from the central control device 14. The gas heated by the heater 25 is sent to the nozzle 20 through the air supply duct 26 and is blown from the nozzle 20 to the strip electrode P. Although not shown in FIG. 2, as shown in FIG. 1, a plurality of nozzles 20 are arranged on the lower side of the belt-like electrode P, and these lower nozzles 20 are connected to the belt-like electrode P. On the other hand, gas is blown from below. The belt-like electrode P in the drying furnace 12 is in a floating state due to the gas blown from below, and the inside of the drying furnace 12 is conveyed in a floating state. In addition, a humidity sensor (not shown) is provided in the air duct 26, and the measured value is sent to the central management device 14.

  Note that the gas on the belt-like electrode P moves in the + Y direction as the belt-like electrode P is transported due to the frictional force generated between the surface of the belt-like electrode P and the gas. In this way, the region of the steady flow field in which the gas moves with the movement of the strip electrode P is referred to as a “boundary layer”. In FIG. 2, the height of the boundary layer is D (for example, D = 10 mm). In addition, D changes according to the conveyance speed V of the strip electrode P. In FIG. 2, the boundary line A of the boundary layer is indicated by a dotted line. In the region above the boundary line A, the gas flow does not flow in the + Y direction according to the transport of the strip electrode P, and is a so-called unsteady flow field. The gas in the drying furnace is discharged to the outside through an exhaust duct (not shown).

  Although not shown in FIGS. 1 and 2, a gas intake pipe 17 is provided in the drying furnace 12 as shown in FIG. 3. The gas intake tube 17 is made of aluminum or stainless steel. The opening 15 of the gas intake pipe 17 is disposed so as to be lower than the boundary line A (the height is equal to or less than D). Further, since the gas in the boundary layer moves together with the strip electrode P, the water evaporated from the surface of the strip electrode P is held in the gas in the boundary layer for a while. Therefore, the gas containing water evaporated from the surface of the strip electrode P can be taken into the gas intake tube 17 as it is.

  The opening 15 has a funnel shape with a diameter of about 40 mm, for example, and has an angle θ (for example, 5.0) so as to open in the opposite direction (−Y direction) to the transport direction (+ Y direction) of the strip electrode P. It is tilted by a degree. Thereby, the gas flowing along with the conveyance of the belt-like electrode P easily enters the opening 15. Note that the opening 15 needs not to be in contact with the strip electrode P, and a sufficient margin for the strip electrode P is required. As described above, since the belt-like electrode P is conveyed in a floating state in the drying furnace 12, the height of the belt-like electrode P slightly varies. Therefore, it is desirable to determine the installation height, diameter, and angle θ of the opening 15 in consideration of the variation.

  Nine gas intake pipes 17 having the same diameter as shown in FIG. 3 are arranged in the drying furnace 12. FIG. 4A shows a layout of the opening 15 of the gas intake pipe 17. As shown in FIG. 4A, three gas intake pipes 17 are arranged in the vicinity of the carry-in port of the drying furnace 12, in the vicinity of the carry-out port, and in the intermediate portion between the carry-in port and the carry-out port. Has been. Here, the position in the Y-axis direction where the opening 15 is provided in the vicinity of the carry-in port is α, the position in the Y-axis direction where the opening 15 is provided in the center is β, and the opening 15 is located in the vicinity of the carry-out port. The provided position in the Y-axis direction is γ. The position α is a position within a distance L1 (eg, L1 = 1000 mm) from the carry-in port of the drying furnace 12, and the position γ is a position within a distance L2 (eg, L2 = 300 mm) from the carry-out port of the drying furnace 12. And

  FIG. 4B shows a view of the arrangement state of the gas intake port 17 as viewed from the + X side. In FIG. 4B, only one gas intake tube 17 is shown at each of the positions α, β, and γ, but as described above, three gas intake tubes 17 are provided at each position. . As shown in FIG. 4B, a total of nine gas intake pipes 17 in which the openings 15 are arranged at the positions α, β, γ, the other opening has a moisture meter as a moisture amount measurement sensor. 53. The moisture meter 53 is a sampling type and samples and measures the amount of moisture contained in the gas obtained through the gas intake port 17. The gas taken in through the opening 15 flows through the gas intake pipe 17 and is quickly sent to the moisture meter 53. The moisture meter 53 measures the moisture contained in the gas. Thereby, for example, compared to installing the moisture meter 53 in the exhaust duct and measuring the amount of moisture contained in the gas, the moisture is measured by the moisture meter 53 after the moisture evaporates from the strip electrode P. Can be shortened.

  The measurement result of each moisture meter 53 is constantly sent to the central control device 14. As described above, since the opening 15 of the gas intake tube 17 is arranged in the boundary layer, the gas obtained through the gas intake tube 17 exists in the vicinity of the strip electrode P and moves together with the transport electrode P. Originally, it is a dry gas blown from the nozzle 20 shown in FIG. Therefore, most of the moisture contained in the gas acquired through the gas intake tube 17 is the moisture evaporated from the portion of the strip electrode P in contact with the gas. For example, the gas taken in through the gas intake tube 17 in which the opening 15 is disposed at the position α includes moisture evaporated from a portion near the position α of the strip electrode P, and the gas is opened at the position β. The gas taken in through the gas intake pipe 17 in which the portion 15 is arranged contains moisture evaporated from a portion near the position β of the strip electrode P, and the opening 15 is arranged at the position γ. The gas taken in through the gas intake pipe 17 contains moisture evaporated from a portion near the position γ of the strip electrode P.

  That is, the moisture content of the gas acquired from the opening portion 15 disposed at the position α indicates the evaporated moisture amount from the portion of the strip electrode P that has just been carried into the carry-in port, and the opening disposed at the position β. The moisture content of the gas acquired from the portion 15 indicates the evaporated moisture content from the portion of the strip electrode P transported through the central portion, and the moisture content of the gas acquired from the opening 15 disposed at the position γ. Indicates the amount of moisture evaporated from the portion of the strip electrode P transported to the vicinity of the carry-out port. In this way, the openings 15 of the respective gas intake pipes 17 are disposed in the drying furnace 12 in a distributed manner at the positions α, β, γ, thereby evaporating from the portion of the strip electrode P that has just been carried into the carry-in port. It is possible to individually measure the amount of water, the amount of evaporated water from the portion of the strip electrode P transported through the center, and the amount of evaporated water from the portion of the strip electrode P transported to the vicinity of the carry-out port. It has become.

  The centralized management device 14 grasps the amount of evaporated water evaporated from specific portions (positions α, β, γ) of the strip electrode P based on the amount of moisture contained in the gas measured by the nine moisture meters 53, The temperature of the heater 25 connected to each nozzle 20 is adjusted. That is, when it is considered that the amount of evaporated water from the strip electrode P is too small from the sampling measurement value of the moisture meter 53, the temperature of the gas blown to the strip electrode P is set high by setting the temperature of the heater 25 high. If the amount of evaporated water from the strip electrode P is too large, the temperature of the heater 25 is set low, and the temperature of the gas blown to the strip electrode P is lowered. Thereby, the dry state of the strip electrode P can be controlled.

  FIG. 5 shows the relationship between the sampling measurement value of the moisture meter 53 and the sampling measurement value of the residual moisture amount of the strip electrode P measured by the gravimetric method. As shown in FIG. 5, the residual moisture amount of the strip electrode P at that time is uniquely determined from the sampling measurement value of the moisture meter 53. The central management device 14 has a table that stores the relationship between the sampling measurement value of the moisture meter 53 as shown in FIG. 5 and the amount of residual moisture contained in the strip electrode P. The central management device 14 adjusts the temperature of each heater 25 so that the amount of residual moisture contained in the strip electrode P is finally within an allowable value.

  Note that the sampling measurement value of the moisture meter 53 is displayed and stored in the centralized management device 14. Further, in the drying furnace 12, sensors for measuring various environmental conditions in the drying furnace 12 such as a temperature sensor (for example, a thermocouple) that measures temperature and a speed sensor that measures the conveyance speed of the strip electrode P. (All not shown) are installed, and the centralized management device 14 controls the temperature of the gas blown to the strip electrode P based on those measured values, and various environmental conditions in the drying furnace 12, Display and record.

  As shown in FIG. 4B, the lengths of the nine gas intake pipes 17 are set to be as short as possible. In this way, the time from when the gas is taken in through the opening 15 until it reaches the moisture meter 53 can be shortened, so that the measurement delay can be reduced. Since each gas intake pipe 17 is arranged independently, it is possible to shorten the length of the pipe as much as possible without considering the relationship with other pipes.

  Further, as shown in FIG. 4B, the lengths of the nine gas intake pipes are substantially equal. Thereby, the measurement delay of the evaporated water amount of the strip electrode P can be made uniform in each tube. Thereby, since the time to reach the moisture meter 53 after the gas is taken in from the opening 15 is almost constant in each tube, the measurement delay of the evaporated moisture amount at each position (α, β, γ) is made uniform. Will be able to. As a result, variation in the measurement result of the evaporated water amount at each position can be reduced.

  FIG. 6 shows how sampling measurement values of the moisture meter 53 fluctuate at positions α, β, and γ. In FIG. 6, three variation examples of the sampling measurement value of the moisture meter 53 between the positions α to γ are indicated by broken lines A to C, respectively. The vertical axis of the graph in FIG. 6 indicates that the sampling measurement value of the moisture meter 53 becomes smaller (that is, the amount of evaporated water from the strip electrode P decreases) as it goes upward.

  In the polygonal line A, the sampling measurement value (amount of evaporated water from the strip electrode P) of the moisture meter 53 is small in the first half from the position α to the position β, and the latter half from the position β to the position γ. Compared with the first half, the sampling measurement value of the moisture meter 53 (the amount of evaporated water from the strip electrode P) is larger. That is, in this case, the dry state of the strip electrode P is gentle in the first half, and the dry state of the strip electrode P is strong in the second half. FIG. 7 schematically shows how the coating solution 29 changes when the sampling measurement value of the moisture meter 53 changes along the polygonal line A. As shown in FIG. 7, the electrode main material 71 and the binder 73 in the coating liquid 29 are not detached from the electrode base material 27, and they are held at the positions at the time of application. That is, in this case, the binder 72 is not unevenly distributed, and the state of the coating liquid 29 is good.

  In the polygonal line B, the sampling measurement value of the moisture meter 53 at the position β (central part) is larger than the polygonal line A, and the dry state of the strip electrode P in the first half from the position α to the position β is the polygonal line A. It is stronger than when. FIG. 7 also shows how the coating liquid 29 changes when the sampling measurement value of the moisture meter 53 changes along the polygonal line B. In this case, the electrode main material 71 and a part of the binder 73 are detached from the electrode base material 27.

  In the broken line C, the sampling measurement value of the moisture meter 53 is the largest at the position β (center part), and the dry state of the strip electrode P in the first half part from the position α to the position β is the strongest. FIG. 7 also shows how the coating solution 29 changes when the sampling measurement value of the moisture meter 53 changes along the polygonal line C. In this case, the evaporation of water from the strip electrode P in the first half portion becomes abrupt, so that the water inside the strip electrode P also moves to the surface vigorously, and the electrode main body is moved by the movement of the moisture. The material 71 and the binder 73 are also lifted to the surface of the coating liquid 29, and the entire coating liquid 29 is detached from the electrode substrate 27, so that the binder 73 and the like are unevenly distributed.

  From the above, at the initial drying stage in the first half from the carry-in port to the central part, moisture is gently evaporated from the strip electrode P so that the sampling measurement value of the moisture meter 53 changes along the polygonal line A. In the latter half part from the part to the carry-out port, it can be said that it is desirable to increase the amount of evaporated water from the strip electrode P by increasing the dry state. Therefore, the central control device 14 adjusts the temperature of the gas in the drying furnace 12 so that the sampling measurement values of the moisture meter 53 at the positions α, β, and γ change along the polygonal line A in FIG.

  Here, in the polygonal line A, the evaporated moisture amount of the strip electrode P at the position α is S1, the evaporated moisture amount of the strip electrode P at the position β is S2, and the evaporated moisture amount of the strip electrode P at the position γ is S3. And First, as shown in FIG. 8A, the centralized management device 14 is sprayed on the strip electrode P around the carry-in port so that the sampling measurement value of the moisture meter 53 is always S1 at the position α. The temperature of the heater 25 that heats the gas is adjusted. Further, as shown in FIG. 8B, for the position β, the heater that heats the gas blown to the strip electrode P around the center so that the sampling measurement value of the moisture meter 53 is always S2. Adjust the temperature of 25. Further, as shown in FIG. 8C, for the position γ, the heater that heats the gas blown to the strip electrode P around the carry-out portion so that the sampling measurement value of the moisture meter 53 is always S3. Adjust the temperature of 25.

  Note that the value of S3 in FIG. 6 is a sampling measurement value corresponding to the amount of water finally contained in the strip electrode P, but in order to guarantee the manufacturing quality of the electrode, the amount of water contained in the strip electrode P is It is necessary to make it equal to or less than the allowable value shown in FIG. Therefore, as S3, a numerical value is set such that the amount of water contained in the strip electrode P is within an allowable value. As described above, the centralized management device 14 has a table indicating the relationship between the sampling measurement value of the moisture meter 53 and the measurement value of the moisture amount contained in the coating film 29 (measurement value by gravimetric method). The temperature of the heater 25 is adjusted so that the measured value of the moisture content of the gas taken in via the gas intake pipe 17 near the carry-out port becomes S3, and the moisture content contained in the strip electrode P is within an allowable value. It is trying to become.

  As described above in detail, according to the present embodiment, the opening 15 of the gas intake tube 17 is provided in the boundary layer generated in the gas blown to the strip electrode P, so that the gas intake tube In 17, a gas that moves together with the belt-like electrode P due to friction with the surface of the belt-like electrode P, that is, a gas containing the amount of water evaporated from the surface of the belt-like electrode P can be taken in as it is. Since the moisture meter 53 measures the amount of moisture contained in the gas taken in through the gas intake tube 17, it is possible to accurately measure the amount of evaporated water from each part of the strip electrode P without delay. Will be able to.

  Further, according to the present embodiment, the opening 15 of the gas intake pipe 17 is inclined by an angle θ so as to open in the direction opposite to the transport direction (+ Y direction) of the electrode base material 27 (−Y direction). ing. In this way, the gas flowing along with the transport of the strip electrode P can be easily taken into the gas intake tube 17, so that the measurement accuracy of the amount of evaporated water from the strip electrode P by the moisture meter 53 is further improved.

  Further, according to the present embodiment, the three gas intake pipes 17 in which the openings 15 are arranged in the vicinity of the carry-in entrance (position α) of the transport device 12 and the openings 15 are arranged in the vicinity of the carry-out exit (position γ). There are provided three gas intake pipes 17 and three gas intake pipes 17 each having an opening 15 disposed at an intermediate portion (position β) between the carry-in port and the carry-out port. In addition, for each gas intake tube 17, a moisture meter 53 for measuring the moisture content of the gas taken in from each gas intake tube 17 is provided. As a result, it becomes possible to grasp the amount of evaporated water in each portion of the strip electrode P (portion passing through the positions α, β, γ) and grasp the drying unevenness of the strip electrode P. The drying state of the strip electrode P can be controlled so as to reduce the drying unevenness of the strip electrode P.

  In the present embodiment, the gas intake pipe 17 is disposed in the vicinity of the carry-in entrance (position α), the central portion (position β), and the carry-out exit (position γ). When trying to measure in detail, the gas intake pipes 17 may be installed in more places.

  Moreover, in this embodiment, the length of all the gas intake pipes 17 is set so that it may become substantially equal. In this way, the delay in measurement of the evaporated water amount at each position (α, β, γ) can be made uniform, thereby reducing variations in the measurement result of the evaporated water amount at each position. Will be able to.

  Further, in the present embodiment, the centralized management device 14 blows the belt-like electrode P in the first half so that the belt-like electrode P conveyed from the carry-in port of the drying furnace 12 to the middle portion is gently dried. The temperature of the gas to be applied is adjusted, and the belt-like electrode P transported in the latter half from the intermediate part to the carry-out port is sprayed on the belt-like electrode P in the latter half so that the dry state is stronger than the former half. Adjust the temperature of the gas produced. By doing so, the separation of the coating film 29 from the electrode substrate 27 and the uneven distribution of the binder 73 are prevented.

  In addition, what is adjusted by the centralized management apparatus 14 is not restricted to the temperature of the gas sprayed on the strip electrode P. For example, the flow rate of the gas blown to the strip electrode P may be adjusted, or the humidity of the gas may be adjusted. The point is that the physical quantity to be adjusted is a physical quantity related to the gas blown to the strip electrode P and may be a physical amount that affects the amount of evaporated water from the strip electrode P.

  Further, according to the present embodiment, the centralized management device 14 determines the relationship between the sampling measurement value measured by the moisture meter 53 (that is, the amount of evaporated water of the strip electrode P) and the amount of water contained in the strip electrode P. The temperature of the gas blown to the strip electrode P is adjusted so that the final amount of water contained in the strip electrode P is within an allowable value. As a result, the amount of water contained in the strip electrode P dried in the drying furnace 12 is always equal to or less than the allowable value, and the quality of the manufactured strip electrode P is improved.

  In the present embodiment, three gas intake pipes 17 are arranged in the vicinity of the transport inlet, the central portion, and the transport outlet in the drying furnace 12, but any number of the gas intake pipes 17 may be used. The number of 17 installed can be appropriately determined according to the width of the electrode substrate 27, the state of the coating liquid to be applied, and the like.

It is the schematic which shows the structure of the electrode manufacturing apparatus which concerns on one Embodiment of this invention. It is a figure for demonstrating the flow of the gas in a conveying apparatus. It is a figure which shows the opening part of a gas intake tube. It is a graph which shows the relationship between a sensor measured value and the moisture content of a coating liquid. FIG. 5A is a view showing the arrangement of the openings of the gas intake pipe, and FIG. 5B is a view of the arrangement of the gas intake 17 viewed from the side. It is a graph which shows the mode of the change of the amount of evaporating water. It is a schematic diagram which shows the mode of the change of a coating liquid. FIG. 8A is a graph showing how the sampling measurement value fluctuates at the position α, and FIG. 8B is a graph showing how the sampling measurement value fluctuates at the position β. (C) is a graph which shows the fluctuation | variation state of the sampling measurement value in the position (gamma).

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Electrode manufacturing apparatus 11 Coating apparatus 12 Drying furnace 13 Winding apparatus 14 Centralized control apparatus 15 Opening part 17 Gas intake pipe 20 Nozzle 25 Heater 26 Air duct 27 Electrode base material 29 Coating liquid 31 Nozzle 53 Moisture meter 71 Electrode main material 73 Binder P Strip electrode

Claims (6)

An electrode manufacturing apparatus having a drying furnace for drying the belt-shaped electrode that is continuously conveyed,
A gas in which an opening is arranged in a boundary layer that is a steady flow field generated when the gas blown to the strip electrode transported in the drying furnace moves as the strip electrode moves. An intake tube;
An electrode manufacturing apparatus comprising: a moisture content measurement sensor that measures a moisture content of a gas introduced through the gas intake tube. In the gas intake pipe,
The electrode manufacturing apparatus according to claim 1, wherein the opening is installed so as to open in a direction opposite to a conveying direction of the strip electrode. The gas intake pipe in which the opening is disposed in the vicinity of the carry-in entrance of the transfer furnace, the gas intake pipe in which the opening is disposed in the vicinity of a carry-out exit of the transfer furnace, the carry-in inlet and the carry-out outlet The gas intake pipe in which the opening is arranged in the middle of
The electrode manufacturing apparatus according to claim 1, further comprising: the water content measurement sensor provided for each of the gas intake pipes.   The electrode manufacturing apparatus according to claim 3, wherein the length of the gas intake pipe is set to be substantially equal. A physical quantity relating to the gas blown to the strip electrode in the front half so that the strip electrode transported in the first half from the carry-in entrance to the intermediate portion is gently dried, and from the strip electrode Adjust the physical quantity that affects the amount of evaporated water,
The belt-like electrode transported in the latter half part from the intermediate part to the carry-out port is further provided with an adjusting device for adjusting the physical quantity in the latter part so that the dry state is stronger than that in the first half part. The electrode manufacturing apparatus according to claim 3 or 4, characterized in that: The adjusting device comprises:
Having a table showing the relationship between the measured value of the amount of moisture contained in the gas taken in through the gas intake tube and the amount of moisture contained in the strip electrode,
The electrode manufacturing apparatus according to claim 5, wherein the physical quantity is adjusted so that a moisture amount contained in a portion of the belt-like electrode near the carry-out port is within an allowable value.

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