JP6531289B2 - Vacuum drying apparatus, vacuum drying system, vacuum drying method, and method of manufacturing battery electrode - Google Patents

Description

  The present invention relates to a vacuum drying apparatus, a vacuum drying system, a vacuum drying method, and a method of manufacturing a battery electrode.

  Conventionally, a technique for vacuum drying a material to be dried has been proposed (see, for example, Patent Document 1).

JP 2005-140536 A

  The method disclosed in Patent Document 1 and the method disclosed in Patent Document 1 aim to accurately determine the end of vacuum drying to suppress the occurrence of overdrying and insufficient drying. And As described above, although there is a problem of terminating vacuum drying in an optimum state, various improvements have been made even at present, and there has been no satisfactory technique for determining the completion of vacuum drying. In particular, when drying an electrode of a secondary battery such as a lithium ion battery, the battery manufactured using the electrode may not be able to exhibit desired performance as a battery if the electrode can not be sufficiently dried. there were.

  Then, this invention is made in view of said subject, and it aims at completing vacuum drying in an optimal state.

  The present invention proposes the following matters in order to solve the above-mentioned problems. In addition, in order to make an understanding easy, although the code | symbol corresponding to embodiment of this invention is attached and demonstrated, it is not limited to this.

  (1) The present invention is a vacuum drying apparatus (for example, FIG. 1) for vacuum-drying a material to be dried (for example, corresponding to a battery electrode described later) disposed in a drying furnace (for example, corresponding to drying (Corresponding to the vacuum drying device 1 of 1), wherein the pressure measuring means (for example, corresponding to the pressure measuring unit 12 in FIG. 1) for measuring the pressure in the drying furnace and the pressure measured by the pressure measuring means A determination means (for example, corresponding to the determination unit 13 of FIG. 1) for determining whether or not the pressure has fallen below or below a predetermined target pressure, and the pressure measured by the pressure measuring means is the target pressure Vacuum drying control means (for example, the vacuum drying control unit 14 of FIG. 1) which continues vacuum drying for a predetermined first time after it is determined by the determining means that the pressure has dropped below or below the target pressure. Equivalent to) If it is determined by the determination means that the pressure measured by the pressure measurement means has dropped below the target pressure or below the target pressure after the first time has elapsed, vacuum drying of the material to be dried is performed. And a determination unit (for example, corresponding to the determination unit 15 in FIG. 1) that determines that the process has been completed.

  According to the present invention, the pressure in the drying furnace is measured by the pressure measuring means. Further, it is determined by the determination means whether or not the pressure measured by the pressure measurement means has dropped below the target pressure or below the target pressure. In addition, when the vacuum drying control means determines that the pressure measured by the pressure measuring means has dropped below the target pressure or lower than the target pressure by the determining means, the vacuum drying is continued for the first time. And For this reason, even after it is determined that the pressure in the drying furnace has dropped below the target pressure or below the target pressure, the vacuum drying is continued for the first time, which largely depends on the setting accuracy of the target pressure. Without drying, the occurrence of insufficient drying can be suppressed.

  Further, according to the present invention, by setting the first time, it is possible to prevent the time during which the vacuum drying is being performed from being extended excessively, and to suppress the occurrence of the overdrying.

  Further, according to the present invention, when it is judged by the judging means that the pressure measured by the pressure measuring means after the first time has elapsed has been lowered by the target pressure or lower than the target pressure, It was determined that vacuum drying of the dried material was completed. For this reason, when the material to be dried has become insufficiently dried due to an unexpected situation in a period in which vacuum drying is continued for the first time, vacuum drying of the material to be dried is completed. It can be determined that the vacuum drying is not complete, and it can be prevented that the vacuum drying is erroneously determined to be completed despite the insufficient drying.

  (2) The present invention provides the vacuum drying device according to (1), including a timer (for example, corresponding to the timer unit 16 in FIG. 3) for measuring the time after starting the vacuum drying of the material to be dried. The vacuum drying apparatus is characterized in that the determination by the determination means is paused in a period until the time measured by the time counting means passes a second predetermined time.

  According to this invention, in the vacuum drying apparatus of (1), the time after starting vacuum drying of the material to be dried is measured by the clocking means, and the time measured by the clocking means passes the second time. In the period up to, the determination by the determination means is suspended. For this reason, by setting the second time, the determination by the determination means can be paused in a period in which it is surely known that the vacuum drying of the material to be dried has not been completed.

  (3) With respect to the vacuum drying apparatus of (1) or (2), the present invention corresponds to a predetermined environment (for example, the dry room 2 of FIG. In this case, a vacuum drying apparatus is proposed in which a pressure lower than the saturated water vapor pressure at the dew point in the predetermined environment is set as the target pressure.

  According to the present invention, in the vacuum drying device of (1) or (2), assuming that the environment in which the object to be dried is disposed after completion of vacuum drying is a predetermined environment, the saturated water vapor pressure at the dew point in the predetermined environment Low pressure was set as the target pressure. For this reason, since the setting accuracy of the target pressure which becomes the judgment standard of the completion of vacuum drying can be improved, generation of insufficient drying can be suppressed more reliably, and the first time for continuing vacuum drying can be further improved. It can be shortened.

  In addition, the target pressure is optimized by repeating the procedure of appropriately setting the target pressure and the procedure of measuring the amount of water contained in the material to be dried after vacuum drying is completed and evaluating the performance of the material to be dried. It is conceivable to find a value. Therefore, according to the present invention, in the vacuum drying device of (1) or (2), a pressure lower than the saturated water vapor pressure at the dew point in the predetermined environment is set as the target pressure. Therefore, when finding the optimum value of the target pressure, it is possible to set the initial value of the target pressure with the saturated water vapor pressure at the dew point in the predetermined environment as a standard. Therefore, since an appropriate value can be set as the initial value of the target pressure as compared with the case where the initial value of the target pressure is set in the absence of a standard, the number of repeating the above two procedures can be reduced. And the optimum value of the target pressure can be found in a short time.

  (4) In the vacuum drying apparatus of (3), when the dew point (degrees Celsius) in the predetermined environment is t and the constants determined in advance are a and b, saturation at the dew point in the predetermined environment There is proposed a vacuum drying apparatus characterized in that the water vapor pressure e is obtained by the following equation (1).

  According to the present invention, in the vacuum drying apparatus of (3), the saturated water vapor pressure at the dew point in a predetermined environment is determined without using a complicated method according to the above-mentioned equation (1) known as the equation of tetens. be able to.

  (5) In the vacuum drying apparatus according to (3) or (4) of the present invention, the target pressure is set to a pressure lower than the saturated water vapor pressure at the dew point in the predetermined environment. A vacuum drying apparatus is proposed which is characterized in that it is determined according to the material.

  The material to be dried after the completion of vacuum drying absorbs moisture according to the material of the material to be dried during a period of time in which the material is placed in a predetermined environment. Therefore, according to the present invention, in the vacuum drying device of (3) or (4), the target pressure is set to a pressure lower than the saturated water vapor pressure at the dew point in a predetermined environment. We decided to decide accordingly. Therefore, the target pressure can be set in accordance with the hygroscopicity of the material to be dried in a predetermined environment.

  (6) In the vacuum drying device according to any one of (1) to (5), in the present invention, the determination means detects abnormality of the vacuum drying device based on the pressure measured by the pressure measurement means. The vacuum drying apparatus is proposed which is characterized by performing an output indicating an abnormality when it is determined that the abnormality is present.

  According to the present invention, in the vacuum drying device according to any one of (1) to (5), the determination means performs abnormality detection of the vacuum drying device based on the pressure measured by the pressure measurement means, When it is determined that there is an output, an output indicating an abnormality is performed. For this reason, it is possible to detect and output an abnormality of the vacuum drying apparatus while determining the completion of vacuum drying.

  (7) The present invention proposes the vacuum dryer according to any one of (1) to (6), wherein the material to be dried is a battery electrode.

  According to this invention, in the vacuum drying apparatus according to any one of (1) to (6), the material to be dried is the battery electrode. For this reason, the occurrence of insufficient drying of the battery electrode can be suppressed.

  (8) The present invention relates to a vacuum drying apparatus according to any one of (1) to (7) and a drying room (for example, as shown in FIG. 1) in which the material to be dried is placed after vacuum drying by the vacuum drying apparatus. A vacuum drying system (for example, corresponding to the vacuum drying system AA in FIG. 1), and after it is determined by the determination means that the vacuum drying of the material to be dried is completed, The vacuum drying system characterized by transferring the said to-be-dried material from the said drying furnace to the said dry room is proposed.

  According to the present invention, a vacuum drying system comprising: the vacuum drying device according to any one of (1) to (7); and a drying room in which a material to be dried is disposed after completion of vacuum drying by the vacuum drying device. After it is judged by the judging means that the vacuum drying of the material to be dried is completed, the material to be dried is transferred from the drying furnace to the drying room. Therefore, after the material to be dried is transferred from the drying furnace to the drying room, vacuum drying can be performed on a new material to be dried by the vacuum drying apparatus.

  (9) The present invention is a vacuum drying method for vacuum drying a material to be dried (for example, corresponding to a battery electrode described later) disposed in a drying furnace (for example, corresponding to the drying furnace 11 in FIG. 1). A first step of measuring the pressure in the drying furnace, and a second step of determining whether or not the pressure measured in the first step has fallen below or below a predetermined target pressure. And a vacuum for a first predetermined time after it is determined in the second step that the pressure measured in the first step has dropped below or below the target pressure. A third step of continuing drying, a fourth step of measuring the pressure in the drying furnace after the first time has elapsed, and a pressure measured in the fourth step is less than the target pressure Or A fifth step of determining whether or not the pressure has dropped below the target pressure, and determining that the pressure measured in the fourth step has dropped below the target pressure or below the target pressure in the fifth step , The sixth step of determining that the vacuum drying of the material to be dried has been completed, and the region, which is determined to have the vacuum drying determined by the sixth step, to a predetermined environment And a seventh step of transferring from the drying furnace (corresponding to, for example, the dry room 2 in FIG. 1). The vacuum drying method is proposed.

  According to the present invention, the same effects as those described above can be obtained.

  (10) The present invention further comprises an eighth step of measuring the time from when vacuum drying of the material to be dried is started, according to the vacuum drying method of (9), wherein the measurement is performed by the eighth step A vacuum drying method is proposed, characterized in that the determination in the second step is suspended in a period until a predetermined second time has passed.

  According to the present invention, the same effects as those described above can be obtained.

  (11) The present invention proposes, as the vacuum drying method of (9) or (10), a vacuum drying method characterized in that a pressure lower than the saturated water vapor pressure at the dew point in the predetermined environment is set as the target pressure. doing.

  According to the present invention, the same effects as those described above can be obtained.

  (12) In the vacuum drying method according to (11), when the dew point (Celsius) in the predetermined environment is t and the predetermined constants are a and b, saturation at the dew point in the predetermined environment is obtained. A vacuum drying method is proposed, which is characterized in that the water vapor pressure e is determined by the following equation (2).

  According to the present invention, the same effects as those described above can be obtained.

  (13) In the vacuum drying method according to (11) or (12), according to the present invention, the target pressure is set to a pressure lower than the saturated water vapor pressure at the dew point in the predetermined environment. We propose a vacuum drying method characterized in that it is determined according to the material.

  According to the present invention, the same effects as those described above can be obtained.

  (14) The present invention relates to the vacuum drying method according to any one of (9) to (13), wherein in the second step, the material to be dried is determined based on the pressure measured in the first step. A vacuum drying method is proposed, which is characterized in that abnormality detection of a vacuum drying device to be vacuum dried is performed.

  According to the present invention, the same effects as those described above can be obtained.

  (15) The present invention proposes the vacuum drying method according to any one of (9) to (14), characterized in that the material to be dried is a battery electrode.

  According to the present invention, the same effects as those described above can be obtained.

  (16) The present invention is a method of manufacturing a battery electrode for vacuum-drying a battery electrode disposed in a drying furnace (for example, corresponding to the drying furnace 11 in FIG. 1), and measuring the pressure in the drying furnace A first step, a second step of determining whether the pressure measured in the first step has dropped below or below a predetermined target pressure, and the first step A third step of continuing vacuum drying for a first predetermined time after it is determined in the second step that the measured pressure has fallen below or below the target pressure; After the first time period has elapsed, a fourth step of measuring the pressure in the drying furnace and a pressure measured in the fourth step falling below the target pressure or below the target pressure And the battery electrode when it is determined in the fifth step that the pressure measured in the fourth step is lower than or less than the target pressure or lower than the target pressure. A sixth step of determining that the vacuum drying has been completed, and a battery electrode determined to have completed vacuum drying in the sixth step in a region adjusted to a predetermined environment (for example, the dry room 2 of FIG. And the seventh step of transferring the material from the drying furnace).

  According to this invention, when manufacturing a battery electrode, the same effect as the effect mentioned above can be produced.

  According to the present invention, vacuum drying can be completed in an optimal state.

It is a block diagram of a vacuum drying device concerning a 1st embodiment of the present invention. It is a figure which shows the state of the water which changes according to temperature and pressure. It is a block diagram of a vacuum drying device concerning a 2nd embodiment of the present invention.

  Hereinafter, embodiments of the present invention will be described in detail using the drawings. In addition, the component in the following embodiment can be suitably substituted with the existing component etc., and various variations including combinations with other existing components are possible. Therefore, the following description of the embodiments does not limit the contents of the invention described in the claims.

First Embodiment
FIG. 1 is a block diagram of a vacuum drying system AA according to a first embodiment of the present invention. The vacuum drying system AA includes a vacuum drying device 1 for vacuum-drying a battery electrode, and a dry room 2 in which the battery electrode is disposed after completion of vacuum drying by the vacuum drying device 1.

  The vacuum drying apparatus 1 includes a drying furnace 11, a pressure measurement unit 12, a determination unit 13, a vacuum drying control unit 14, and a determination unit 15. The vacuum drying of the battery electrode disposed in the drying furnace 11 is carried out Remove water contained in

  The pressure measurement unit 12 measures the pressure inside the drying furnace 11.

  The determination unit 13 determines whether the pressure measured by the pressure measurement unit 12 has become equal to or less than a predetermined target pressure. The setting of the above-mentioned target pressure will be described in detail below using FIG.

  As shown in FIG. 2, water changes its state according to temperature and pressure. Therefore, first, the saturated water vapor pressure e at the dew point in the dry room 2 is determined by substituting the dew point (degrees Celsius) in the dry room 2 where the battery electrode is disposed after the completion of vacuum drying into t in the following formula (3). . In Equation (3), a and b are predetermined constants, and these constants a and b are uniquely determined when water contained in the battery electrode is water and ice, respectively. .

  In addition, in the dry room 2, in order to prevent moisture from adhering to the transferred battery electrode, setting of a threshold based on the dew point of the dry room 2 is performed, and environmental adjustment by air conditioning is performed to maintain a desired dew point. It will be. According to the above equation (3), the pressure that is the basis of the above threshold is determined.

  Next, a pressure lower than the saturated water vapor pressure e at the dew point in the dry room 2 is set as the above-mentioned target pressure.

  Here, first, temporarily, a pressure higher than the saturated water vapor pressure e at the dew point in the dry room 2 is set as the above-mentioned target pressure, and a saturated water vapor pressure e at the dew point in the dry room 2 is set, Are discussed below. In these cases, it is determined that the vacuum drying of the battery electrode is completed in a state where the pressure in the drying furnace 11 is equal to or higher than the saturated water vapor pressure e at the dew point in the dry room 2, and the drying becomes insufficient.

  Next, temporarily, a pressure that is excessively lower than the saturated water vapor pressure e at the dew point in the dry room 2 will be examined below as a case where the above-mentioned target pressure is set. In this case, excessive drying occurs, and the water content contained in the battery electrode is reduced as compared with the case where the target pressure is appropriately set. However, if this battery electrode is placed in the dry room 2 after the vacuum drying is completed, the battery electrode absorbs moisture until the battery electrode contains a quantity of water equilibrated by the saturated water vapor pressure in the dry room 2 . Therefore, when a target pressure is a pressure that is excessively lower than the saturated water vapor pressure e at the dew point in the dry room 2, a suitable pressure lower than the saturated water vapor pressure at the dew point in the dry room 2 is the target pressure As a result, the vacuum drying process is wasted.

  However, the hygroscopicity of the battery electrode differs depending on the material of the battery electrode. For this reason, it is preferable to determine, according to the material of the battery electrode, how low the pressure is to be set as the target pressure described above with respect to the saturated water vapor pressure e at the dew point in the dry room 2.

  Returning to FIG. 1, after the vacuum drying control unit 14 determines that the pressure measured by the pressure measurement unit 12 has become equal to or less than the above-described target pressure, the vacuum drying control unit 14 spans a first predetermined time. And continue vacuum drying. The first time may be a predetermined fixed value or a variable value appropriately determined.

  First, the case where the first time is a fixed value will be described below. For example, if the setting accuracy of the target pressure is equal to or higher than a predetermined accuracy, or if the degree of easiness of drying of the battery electrode is equal to or higher than a predetermined degree, the first time is set short. If the setting accuracy of the target pressure is lower than the predetermined accuracy, or if the degree of dryness of the battery electrode is less than the predetermined degree, the first time may be set longer. Good. Also, for example, as the setting accuracy of the target pressure becomes higher, the first time may be set shorter. Also, for example, the first time may be set to be shorter as the degree of dryability of the battery electrode becomes higher.

  Next, the case where the first time is a variable value will be described below. For example, if the time until the determination unit 13 determines that the pressure measured by the pressure measurement unit 12 has become equal to or lower than the target pressure after starting vacuum drying is equal to or longer than a predetermined time, drying is insufficient In order to avoid this, the first time is set long, and the time from when vacuum drying is started to when it is determined by the determination unit 13 that the pressure measured by the pressure measurement unit 12 has become equal to or less than the target pressure If the time is less than a predetermined time, the first time may be set short in order to avoid overdrying. Also, for example, as the time until the determination unit 13 determines that the pressure measured by the pressure measurement unit 12 has become equal to or lower than the target pressure after starting vacuum drying, the above-described first time is lengthened. It may be set.

  When the determination unit 13 determines that the pressure measured by the pressure measurement unit 12 is equal to or less than the above-described target pressure after the first time has elapsed, the determination unit 15 determines that the vacuum drying of the battery electrode is completed. to decide. When it is determined by the determination unit 15 that the vacuum drying is completed, the vacuum drying device 1 ends the vacuum drying on the battery electrodes disposed in the drying furnace 11 and the battery electrodes from the drying furnace 11 to the dry room 2 To transport.

  According to the vacuum drying system AA and the vacuum drying device 1 described above, the following effects can be achieved.

  The vacuum drying system AA transfers the battery electrode from the drying furnace 11 to the dry room 2 after the judgment unit 15 judges that the vacuum drying of the battery electrode is completed. For this reason, after transferring the battery electrode from the drying furnace 11 to the dry room 2, vacuum drying can be performed on a new battery electrode by the vacuum drying device 1.

  The vacuum drying apparatus 1 measures the pressure in the drying furnace 11 by the pressure measurement unit 12 and determines by the determination unit 13 whether the pressure measured by the pressure measurement unit 12 has become equal to or less than the target pressure. When it is determined by the vacuum drying control unit 14 that the pressure measured by the pressure measurement unit 12 has become equal to or lower than the target pressure, the vacuum drying is continued for the first time. For this reason, even after it is determined that the pressure in the drying furnace 11 has become equal to or less than the target pressure, the vacuum drying is continued for the first time, so that the setting accuracy of the target pressure is not greatly influenced. The occurrence of insufficient drying can be suppressed.

  Further, by setting the first time, the vacuum drying apparatus 1 can prevent the time during which the vacuum drying is performed from being extended excessively, and can suppress the occurrence of overdrying.

  In the vacuum drying apparatus 1, when the determination unit 15 determines that the pressure measured by the pressure measurement unit 12 after the first time has elapsed is equal to or less than the target pressure by the determination unit 15, It is judged that the vacuum drying is completed. For this reason, when the battery electrode is in an insufficiently dried state due to an unexpected situation in a period in which vacuum drying is continued for the first time, the vacuum drying of the battery electrode is not completed. It is possible to prevent the erroneous determination that the vacuum drying is completed despite the insufficient drying.

  Further, the vacuum drying apparatus 1 sets the pressure lower than the saturated water vapor pressure at the dew point in the dry room 2 as the target pressure by the determination unit 13. For this reason, since the setting accuracy of the target pressure which becomes the judgment standard of the completion of vacuum drying can be improved, generation of insufficient drying can be suppressed more reliably, and the first time for continuing vacuum drying can be further improved. It can be shortened.

  In addition, the target pressure is optimized by repeating the procedure of appropriately setting the target pressure and the procedure of measuring the amount of water contained in the material to be dried after vacuum drying is completed and evaluating the performance of the material to be dried. It is conceivable to find a value. Therefore, the vacuum drying apparatus 1 sets a pressure lower than the saturated water vapor pressure at the dew point in the dry room 2 as the target pressure. For this reason, when finding the optimum value of the target pressure, it is possible to set the initial value of the target pressure with the saturated water vapor pressure at the dew point in the dry room 2 as a standard. Therefore, since an appropriate value can be set as the initial value of the target pressure as compared with the case where the initial value of the target pressure is set in the absence of a standard, the number of repeating the above two procedures can be reduced. And the optimum value of the target pressure can be found in a short time.

  Moreover, the vacuum drying apparatus 1 can obtain | require the saturated water vapor pressure in the dew point in the dry room 2 without using a complicated method by above-mentioned Numerical formula (1).

  Further, the vacuum drying apparatus 1 determines how much the target pressure is set to a pressure lower than the saturated water vapor pressure at the dew point in the dry room 2 according to the material of the battery electrode. Therefore, the target pressure can be set according to the hygroscopicity of the battery electrode in the dry room 2.

  The electrode of a secondary battery such as a lithium ion battery has a structure in which an electrode active material layer is formed on metal foil (aluminum or copper), and in the manufacturing process, the electrode active material slurry is formed on the metal foil. By applying a vacuum drying treatment after application, water is removed from the electrode. If the electrode is not sufficiently dried, the desired performance as a secondary battery can not be realized, so it is necessary to ensure sufficient drying. For this reason, when vacuum-drying the electrode of a secondary battery, the vacuum drying apparatus 1 is suitable.

  Moreover, a highly hygroscopic material may be used for the above-mentioned electrode active material. For this reason, when vacuum-drying the electrode of a secondary battery, vacuum-drying system AA which arrange | positions a battery electrode in the dry room 2 after completion of vacuum drying is suitable.

Second Embodiment
FIG. 3 is a block diagram of a vacuum drying system BB according to a second embodiment of the present invention. The vacuum drying system BB differs from the vacuum drying system AA according to the first embodiment of the present invention shown in FIG. 1 in that a vacuum drying device 1A is provided instead of the vacuum drying device 1. In the vacuum drying system BB, the same components as those of the vacuum drying system AA are denoted by the same reference numerals and the description thereof is omitted.

  The vacuum drying apparatus 1A includes a drying furnace 11, a pressure measurement unit 12, a determination unit 13A, a vacuum drying control unit 14, a determination unit 15, and a timer unit 16, and vacuum dries the battery electrodes disposed in the drying furnace 11. To remove water contained in the battery electrode.

  The timer unit 16 measures the time after starting vacuum drying of the battery electrode.

  Similarly to the determination unit 13, the determination unit 13A determines whether the pressure measured by the pressure measurement unit 12 has become equal to or less than a predetermined target pressure. However, in a period until the time measured by the clock unit 16 elapses a predetermined second time, the determination unit 13A determines that the pressure measured by the pressure measurement unit 12 is less than or equal to a predetermined target pressure. Pause the determination of whether it has become. Therefore, the above-described determination by the determination unit 13A is started after the second time has elapsed since vacuum drying of the battery electrode was started.

  Further, the determination unit 13A performs abnormality detection of the vacuum drying apparatus 1A based on the pressure measured by the pressure measurement unit 12, and when it is determined that there is an abnormality, performs an output indicating an abnormality. Specifically, when the pressure measured by the pressure measurement unit 12 is higher than a predetermined upper limit pressure or lower than a predetermined lower limit pressure, the determination unit 13A has an abnormality in the vacuum drying device 1A. It determines that it is occurring, and outputs a signal that reports the occurrence of an abnormality.

  According to the above-mentioned vacuum drying apparatus 1A, in addition to the above-mentioned effect which the vacuum drying apparatus 1 can exhibit, the following effects can be produced.

  The vacuum drying apparatus 1A measures the time from when vacuum drying of the battery electrode is started by the timer unit 16, and in the period until the time measured by the timer unit 16 passes the second time, the determination unit Pause the judgment by 13A. Therefore, by setting the second time, the determination by the determination unit 13A can be paused in a period in which it is known that the vacuum drying of the battery electrode has not been completed.

  In addition, the vacuum drying apparatus 1A performs abnormality detection of the vacuum drying apparatus 1A based on the pressure measured by the pressure measurement unit 12 by the determination unit 13A, and instructs an abnormality when it is determined that it is an abnormality. Make an output. Therefore, it is possible to detect and output an abnormality of the vacuum drying apparatus 1A while determining the completion of the vacuum drying.

  The embodiments of the present invention have been described in detail with reference to the drawings, but the specific configuration is not limited to this embodiment, and includes designs within the scope of the present invention.

  For example, in each of the above-described embodiments, although the object to determine the completion of vacuum drying is the battery electrode, the present invention is not limited thereto.

  In each of the above-described embodiments, the determination units 13 and 13A determine whether the pressure measured by the pressure measurement unit 12 has become equal to or less than the target pressure. However, the present invention is not limited to this, and the determination units 13 and 13A may determine whether the pressure measured by the pressure measurement unit 12 has become less than the target pressure.

AA, BB; vacuum drying system 1, 1A; vacuum drying device 2; drying room 11; drying furnace 12; pressure measurement unit 13, 13A; determination unit 14; vacuum drying control unit 15; determination unit 16;

Claims (16)

A vacuum drying apparatus for vacuum drying a material to be dried disposed in a drying furnace, comprising:
Pressure measuring means for measuring the pressure in the drying furnace;
A determination unit that determines whether the pressure measured by the pressure measurement unit has dropped below or below a predetermined target pressure;
Vacuum drying in which vacuum drying is continued for a first predetermined time after it has been determined by the determination means that the pressure measured by the pressure measurement means has dropped below or below the target pressure. Control means,
If it is determined by the determination means that the pressure measured by the pressure measurement means has dropped below the target pressure or below the target pressure after the first time has elapsed, vacuum drying of the material to be dried is performed. Determining means for determining that the process has been completed;
A vacuum drying apparatus comprising: A clock means for measuring the time after starting the vacuum drying of the material to be dried;
2. The vacuum drying apparatus according to claim 1, wherein the determination by the determination means is paused in a period until the time measured by the clock means passes a second predetermined time.   Assuming that an environment in which the material to be dried is disposed after completion of vacuum drying is a predetermined environment, a pressure lower than a saturated water vapor pressure at a dew point in the predetermined environment is set as the target pressure. Or the vacuum drying apparatus as described in 2. Assuming that the dew point (degrees Celsius) in the predetermined environment is t and the predetermined constants are a and b, the saturated water vapor pressure e at the dew point in the predetermined environment is determined by the following equation (1) The vacuum drying apparatus according to claim 3.

  The vacuum according to claim 3 or 4, wherein it is determined according to the material of the material to be dried that the target pressure is to be set to a pressure lower than the saturated water vapor pressure at the dew point in the predetermined environment. Dryer.   The determination means performs abnormality detection of the vacuum drying apparatus based on the pressure measured by the pressure measurement means, and when it is determined that the abnormality is present, performs an output indicating an abnormality. The vacuum drying apparatus according to any one of claims 1 to 5.   The vacuum dryer according to any one of claims 1 to 6, wherein the material to be dried is a battery electrode. A vacuum drying system comprising: the vacuum drying device according to any one of claims 1 to 7; and a drying room in which the material to be dried is placed after completion of vacuum drying by the vacuum drying device,
A vacuum drying system characterized by transferring the material to be dried from the drying furnace to the drying room after it is determined by the determination means that the vacuum drying of the material to be dried is completed. A vacuum drying method for vacuum drying a material to be dried disposed in a drying furnace, comprising
A first step of measuring the pressure in the drying oven;
A second step of determining whether the pressure measured in the first step has dropped below or below a predetermined target pressure;
The vacuum drying is continued for a first predetermined time after it is determined in the second step that the pressure measured in the first step has dropped below or below the target pressure. The third step of
A fourth step of measuring the pressure in the drying furnace after the first time has elapsed;
A fifth step of determining whether the pressure measured in the fourth step has dropped below or below the target pressure;
Sixth, it is determined that the vacuum drying of the material to be dried is completed when it is determined in the fifth step that the pressure measured in the fourth step has dropped below or below the target pressure. Step and
A seventh step of transferring, from the drying furnace, the material to be dried, which is determined to have been vacuum-dried in the sixth step, to a region adjusted to a predetermined environment;
A vacuum drying method comprising: The method further comprises an eighth step of measuring a time from when vacuum drying of the material to be dried is started,
10. The vacuum drying according to claim 9, wherein the determination in the second step is suspended in a period until the time measured in the eighth step passes a second predetermined time. Method.   11. The vacuum drying method according to claim 9, wherein a pressure lower than a saturated water vapor pressure at a dew point in the predetermined environment is set as the target pressure. Assuming that the dew point (degrees Celsius) in the predetermined environment is t and the predetermined constants are a and b, the saturated water vapor pressure e at the dew point in the predetermined environment is determined by the following equation (2) The vacuum drying method according to claim 11.

  The vacuum according to claim 11 or 12, wherein it is determined according to the material of the material to be dried that the target pressure is set to a pressure lower than the saturated water vapor pressure at the dew point in the predetermined environment. How to dry.   The abnormality detection of a vacuum drying apparatus for vacuum drying the material to be dried is performed based on the pressure measured in the first step in the second step. Vacuum drying method according to one.   The vacuum drying method according to any one of claims 9 to 14, wherein the material to be dried is a battery electrode. A method of manufacturing a battery electrode, comprising: vacuum drying a battery electrode disposed in a drying furnace;
A first step of measuring the pressure in the drying oven;
A second step of determining whether the pressure measured in the first step has dropped below or below a predetermined target pressure;
The vacuum drying is continued for a first predetermined time after it is determined in the second step that the pressure measured in the first step has dropped below or below the target pressure. The third step of
A fourth step of measuring the pressure in the drying furnace after the first time has elapsed;
A fifth step of determining whether the pressure measured in the fourth step has dropped below or below the target pressure;
The sixth step determines that the vacuum drying of the battery electrode is completed when it is determined in the fifth step that the pressure measured in the fourth step has dropped below or below the target pressure. Step and
A seventh step of transferring, from the drying furnace, a battery electrode determined to have completed vacuum drying in the sixth step to a region adjusted to a predetermined environment;
A method of manufacturing a battery electrode comprising:

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