JP6471647B2 - Electrode manufacturing method and electrode manufacturing apparatus - Google Patents

Description

  The present invention relates to an electrode manufacturing method and an electrode manufacturing apparatus.

  In recent years, the development of electric vehicles (EVs) and hybrid electric vehicles (HEVs) has been promoted against the background of the increasing environmental protection movement. As a power source for driving these motors, lithium ion secondary batteries that can be repeatedly charged and discharged have attracted attention. A lithium ion secondary battery is manufactured by alternately laminating electrodes with different polarities via separators.

  The electrodes are manufactured by cutting one by one from a strip electrode material in which active material layers are provided at predetermined intervals on a strip metal foil. In the electrode manufacturing process, the strip-shaped electrode material is intermittently conveyed by a predetermined feed amount, and the electrode is cut out from the end portion of the stopped strip-shaped electrode material.

  The feeding amount of the strip electrode material during intermittent conveyance is corrected by detecting the end of the active material layer provided on the strip electrode material with a sensor (for example, Patent Document 1). When one electrode is cut out from the strip electrode material intermittently conveyed by the corrected feed amount, the length of the active material layer on the electrode is measured, and the coating length of the active material layer is evaluated.

JP 2012-089351 A

  By the way, the strip electrode material is formed by dividing the base material of the strip electrode material formed wide into a plurality of portions in the width direction. Although the active material layer is provided on the wide metal foil at a predetermined interval on the base material of the strip electrode material, the active material layer provided on the metal foil is straight along the width direction of the metal foil. Is not coated and is slightly distorted at the end in the width direction. Therefore, some strip electrode materials obtained by dividing the base material also have distortion (coating sagging) of the active material layer.

  Considering that there is distortion in the active material layer of the strip electrode material, the position in the width direction for measuring the length of the active material layer in the above electrode manufacturing process is to correct the feed amount of the strip electrode material. It is desirable to be the same as the position in the width direction of the end portion of the active material layer to be detected. According to such a configuration, the active material layer strain is not affected by the length of the active material layer to be measured, and the active material layer strain is ignored and the coating length of the active material layer is evaluated. Can do.

  However, the position in the width direction at which the length of the active material layer is measured is detected in order to correct the feed amount of the strip electrode material, for the reason of the device configuration, etc., the position in the width direction of the end portion of the active material layer And may be different. In this case, if the active material layer of the strip electrode material is distorted, an error due to the distortion of the active material layer occurs in the length of the measured active material layer, and the coating length of the active material layer is out of the standard range. There is a problem that the number of electrodes increases.

  The present invention has been made to solve the above-described problems. Accordingly, an object of the present invention is to provide an active material layer even if the position in the width direction for measuring the length of the active material layer of the electrode is different from the position in the width direction for detecting the end portion of the active material layer of the strip electrode material. It is to provide an electrode manufacturing method and an electrode manufacturing apparatus capable of manufacturing an electrode whose coating length falls within a standard range.

  The above object of the present invention is achieved by the following means.

  In the electrode manufacturing method of the present invention, a strip electrode material obtained by dividing a base material of a strip electrode material in which active material layers are provided at predetermined intervals on a strip metal foil in the width direction is cut while being intermittently conveyed. An electrode manufacturing method for manufacturing an electrode from the strip electrode material. The electrode manufacturing method of the present invention includes the steps (a) to (c), and the length of the active material layer at the first position in the width direction of each electrode for the plurality of electrodes manufactured from the strip electrode material. Is obtained in association with the position of the strip electrode material in the width direction of the base material and stored in the storage unit. In the step (a), the information associated with the same position as the position of the strip electrode material in the width direction of the base material is read from the storage unit for the strip electrode material to be cut. The step (b) detects an end portion of the active material layer at a second position different from the first position in the width direction of the electrode for the active material layer provided on the strip-shaped electrode material to be cut. . In the step (c), based on the information read out in the step (a) and the position information of the end portion of the active material layer detected in the step (b), the band to be cut The feed amount of the electrode material is calculated.

  The electrode manufacturing apparatus according to the present invention cuts a belt-shaped electrode material obtained by dividing a base material of a belt-shaped electrode material in which active material layers are provided at predetermined intervals on a belt-shaped metal foil in the width direction, while intermittently conveying the material. An electrode manufacturing apparatus for manufacturing an electrode from the strip electrode material. The electrode manufacturing apparatus of the present invention includes a storage unit, a reading unit, a detection unit, and a calculation unit. In the storage unit, information obtained by measuring the length of the active material layer at the first position in the width direction of each electrode for a plurality of electrodes manufactured from the strip-shaped electrode material is the width of the base material. It is stored in association with the position of the strip electrode material in the direction. The reading unit reads, from the storage unit, the information associated with the same position as the position of the strip electrode material in the width direction of the base material with respect to the strip electrode material to be cut. The detection unit detects an end of the active material layer at a second position different from the first position in the width direction of the electrode for the active material layer provided on the strip-shaped electrode material to be cut. The calculation unit is configured to determine a feed amount of the band-shaped electrode material to be cut based on the information read by the reading unit and the position information of the end of the active material layer detected by the detection unit. calculate.

  According to the present invention, the information on the length of the active material layer acquired for the electrode manufactured from the strip electrode material having similar characteristics of the strain of the active material layer is used to feed the strip electrode material to be cut. Is calculated. For this reason, the distortion of the active material layer of the strip electrode material can be reflected in the feed amount of the strip electrode material. As a result, even if the position in the width direction for measuring the length of the active material layer of the electrode is different from the position in the width direction for detecting the end of the active material layer of the strip electrode material, the coating length of the active material layer is An electrode that falls within the standard range can be manufactured.

1 is a diagram illustrating a schematic configuration of a battery manufacturing system to which an electrode manufacturing apparatus according to an embodiment of the present invention is applied. It is a figure which shows the imaging area of the 1st and 2nd camera with which the positive electrode manufacturing part was equipped. It is a figure for demonstrating a strip | belt-shaped electrode material. It is a figure for demonstrating the coating characteristic of the active material layer in the base material of a strip electrode material. It is a figure for demonstrating the positive electrode manufactured from the strip | belt-shaped electrode material. It is a flowchart which shows the procedure of the electrode manufacturing process by the positive electrode manufacturing part of a 1st manufacturing apparatus. It is a flowchart which shows the procedure of the feed amount calculation process which a calculating part performs. It is a figure for demonstrating the process which calculates the feed amount of a strip | belt-shaped electrode material. It is a figure for demonstrating the process which calculates the moving average value of an error, adding new error information. It is a figure for demonstrating the effect of a feed amount calculation process.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. In addition, the same code | symbol was used for the same member in the figure. In addition, the dimensional ratios in the drawings may be exaggerated for convenience of explanation, and may be different from the actual ratios.

  FIG. 1 is a diagram showing a schematic configuration of a battery manufacturing system 10 to which an electrode manufacturing apparatus according to an embodiment of the present invention is applied.

  As shown in FIG. 1, the battery manufacturing system 10 includes a first manufacturing apparatus 10L and a second manufacturing apparatus 10R that are symmetrical. 1st and 2nd manufacturing apparatus 10L, 10R manufactures the laminated body 40 of the packaged positive electrode 20 and the negative electrode 30, respectively. The packaged positive electrode 20 includes a positive electrode 50 accommodated in a bag-shaped separator. The positive electrode 50 is formed by forming a positive electrode active material layer (hereinafter also simply referred to as “active material layer”) on a metal foil such as an aluminum foil. The negative electrode 30 is formed by forming a negative electrode active material layer on a metal foil such as a copper foil.

  The first and second manufacturing apparatuses 10L and 10R include a positive electrode manufacturing unit 11, a packaged positive electrode manufacturing unit 12, a negative electrode manufacturing unit 13, and an electrode stacking unit 14, respectively.

  The positive electrode manufacturing unit 11 manufactures the positive electrode 50 as an electrode manufacturing apparatus. The positive electrode manufacturing unit 11 manufactures the positive electrode 50 by cutting the belt-shaped electrode material 60 in which the positive electrode active material layers are provided on the belt-shaped metal foil at predetermined intervals while intermittently conveying the strip-shaped electrode material 60. The positive electrode manufacturing unit 11 includes a first camera 15 for detecting the end of the active material layer provided on the strip electrode material 60 and a second camera 16 for measuring the length of the active material layer of the positive electrode 50. Is provided. The first and second cameras 15 and 16 are electrically connected to the calculation unit 17, and the calculation unit 17 is connected to the storage unit 18. The storage unit 18 includes first to third memories 181 to 183. The first to third memories 181 to 183 correspond to first to third strip electrode members 60a to 60c (see FIG. 3) having different coating characteristics of the active material layer. In the first memory 181, error information on the coating length of the active material layer is stored for a plurality of positive electrodes 50 manufactured in the past from the first strip electrode material 60a. The second memory 182 stores error information on the coating length of the active material layer for a plurality of positive electrodes 50 manufactured in the past from the second strip electrode material 60b. In the third memory 183, error information on the coating length of the active material layer is stored for a plurality of positive electrodes 50 manufactured in the past from the third strip electrode material 60c. A detailed description of the positive electrode manufacturing unit 11 will be described later.

  The packaged positive electrode manufacturing unit 12 manufactures the packaged positive electrode 20. The packaged positive electrode manufacturing unit 12 manufactures the packaged positive electrode 20 by housing the positive electrode 50 manufactured by the positive electrode manufacturing unit 11 in a bag-shaped separator.

  The negative electrode manufacturing unit 13 manufactures the negative electrode 30. The negative electrode manufacturing unit 13 manufactures the negative electrode 30 by cutting the belt-shaped electrode material in which the negative electrode active material layers are provided at predetermined intervals on the belt-shaped metal foil while intermittently conveying the strip-shaped electrode material.

  The electrode stacking unit 14 stacks the packaged positive electrode 20 and the negative electrode 30. The electrode stacking unit 14 alternately stacks the packaged positive electrode 20 manufactured by the packaged positive electrode manufacturing unit 12 and the negative electrode 30 manufactured by the negative electrode manufacturing unit 13 by a stacking robot (not shown). The laminated body 40 obtained by alternately laminating the packaged positive electrode 20 and the negative electrode 30 is changed in direction by the rotary table 141 and transferred to the transfer device 70 by a transfer robot (not shown).

  Next, the positive electrode manufacturing unit 11 will be described in more detail with reference to FIG.

  FIG. 2A is a diagram illustrating the imaging regions 151 and 161 of the first and second cameras 15 and 16 provided in the positive electrode manufacturing unit 11 of the first manufacturing apparatus 10L. FIG. 2B is a diagram illustrating the imaging regions 151 and 161 of the first and second cameras 15 and 16 provided in the positive electrode manufacturing unit 11 of the second manufacturing apparatus 10R. The positive electrode manufacturing unit 11 of the first and second manufacturing apparatuses 10L and 10R includes a cutting die (not shown) having the same shape, and manufactures the positive electrodes 50 having the same shape.

  As shown in FIG. 2A, the first camera 15 of the first manufacturing apparatus 10 </ b> L images the end portion 512 of the one side portion 511 of the active material layer 51 provided on the strip electrode material 60. The first image data obtained by imaging the end portion 512 of the active material layer 51 with the first camera 15 is transferred to the calculation unit 17. The calculation unit 17 analyzes the first image data and detects the end portion 512 of the active material layer 51.

  The second camera 16 of the first manufacturing apparatus 10 </ b> L images the entire positive electrode 50 cut out from the strip electrode material 60. Second image data obtained by imaging the positive electrode 50 with the second camera 16 is transferred to the calculation unit 17. The computing unit 17 analyzes the second image data and measures the length of the other side portion (side portion on the tab 52 side) 513 of the active material layer 51.

  As illustrated in FIG. 2B, the first camera 15 of the second manufacturing apparatus 10 </ b> R images the end portion 514 of the other side portion 513 of the active material layer 51 provided on the strip electrode material 60. The first image data obtained by imaging the end 514 of the active material layer 51 with the first camera 15 is transferred to the calculation unit 17. The calculation unit 17 analyzes the first image data and detects the end 514 of the active material layer 51.

  The second camera 16 of the second manufacturing apparatus 10 </ b> R images the entire positive electrode 50 cut out from the strip electrode material 60. Second image data obtained by imaging the positive electrode 50 with the second camera 16 is transferred to the calculation unit 17. The calculation unit 17 analyzes the second image data and measures the length of the other side portion 513 of the active material layer 51.

  The positive electrode manufacturing section 11 of the first and second manufacturing apparatuses 10L and 10R configured as described above manufactures the positive electrode 50 by cutting the strip electrode material 60 while intermittently conveying it. Specifically, the positive electrode manufacturing unit 11 first detects the ends 512 and 514 of the active material layer 51 provided on the strip electrode material 60 and calculates the feed amount of the strip electrode material 60. Then, the positive electrode manufacturing unit 11 conveys the belt-shaped electrode material 60 by the calculated feed amount, cuts the belt-shaped electrode material 60 in a stopped state, and cuts the positive electrode 50. Then, the positive electrode manufacturing unit 11 measures the length of the active material layer 51 of the positive electrode 50 and evaluates the coating length of the active material layer 51 in the positive electrode 50.

  Here, as described above, in the positive electrode manufacturing unit 11 of the first manufacturing apparatus 10L, the position in the width direction of the end portion 512 of the active material layer 51 detected by the first camera 15 and the length by the second camera 16 are increased. The positions in the width direction of the active material layer 51 to be measured are different from each other. On the other hand, in the positive electrode manufacturing unit 11 of the second manufacturing apparatus 10 </ b> R, the position in the width direction of the end portion 514 of the active material layer 51 detected by the first camera 15 and the active material whose length is measured by the second camera 16. The position in the width direction of the layer 51 coincides. For this reason, in the positive electrode manufacturing unit 11 of the first manufacturing apparatus 10L and the positive electrode manufacturing unit 11 of the second manufacturing apparatus 10R, different calculations are executed by the calculation unit 17, and the feed amount of the strip electrode material 60 is calculated. Hereinafter, the operation of the positive electrode manufacturing unit 11 of the first and second manufacturing apparatuses 10L and 10R will be described with reference to FIGS.

  First, the strip-shaped electrode material 60 cut by the positive electrode manufacturing unit 11 will be described with reference to FIGS. FIG. 3 is a diagram for explaining the strip electrode material 60, and FIG. 4 is a diagram for explaining the coating characteristics of the active material layer 510 in the base material 600 of the strip electrode material. FIG. 5 is a diagram for explaining the positive electrode 50 manufactured from the strip electrode material 60.

  As shown in FIG. 3, the strip-shaped electrode material 60 of the present embodiment includes a strip-shaped electrode material base material (mother roll) 600 in which active material layers 510 are provided on a strip-shaped metal foil 610 at predetermined intervals in the width direction. Divided into two. The positive electrode manufacturing unit 11 manufactures the positive electrode 50 by cutting the stopped strip-shaped electrode material 60 while intermittently transporting the strip-shaped electrode material (slit roll) 60 obtained by dividing the base material 600 into three.

  Here, as shown in FIG. 4B as a comparative example, it is desirable that the base material 600 of the strip-shaped electrode material is coated with the active material layer 510 straight on the strip-shaped metal foil 610 in the width direction. . However, as shown in FIG. 4A, the active material layer 510 is not applied straight to the base material 600 of the strip electrode material in the width direction, and at the end in the width direction of the active material layer 510. There is a slight distortion (hereinafter also referred to as “coating sagging”).

  For this reason, as shown to FIG. 5 (A), at least the edge part of the width direction of the base material 600 among the 1st-3rd strip | belt-shaped electrode materials 60a-60c obtained by dividing | segmenting the base material 600 into three. The sagging of the active material layer 51 exists in the first and third strip electrode members 60a and 60c located. Then, as shown in FIG. 5B, there is a possibility that a coating length error due to coating sagging of the active material layer 51 may occur in the positive electrode 50 manufactured from the first and third strip electrode materials 60 a and 60 c. is there.

  Here, the characteristics of the sagging of the active material layer 51 provided on the strip electrode material 60 differ depending on the position of the strip electrode material 60 in the width direction of the base material 600. On the other hand, the characteristics of the sagging of the active material layer 51 are similar between the plurality of active material layers 51 included in one band-shaped electrode material 60, and a plurality of the base materials 600 whose positions in the width direction are the same. This is similar between the active material layers 51 of the strip-shaped electrode material 60.

  The coating sagging of the active material layer 51 of the strip electrode material 60 is such that the position in the width direction in which the length of the active material layer 51 of the positive electrode 50 is measured is the width at which the end of the active material layer 51 is detected. In the positive electrode manufacturing unit 11 of the second manufacturing apparatus 10R that coincides with the position in the direction, the influence can be ignored. However, in the positive electrode manufacturing unit 11 of the first manufacturing apparatus 10L, the position in the width direction for measuring the length of the active material layer 51 of the positive electrode 50 is different from the position in the width direction for detecting the end of the active material layer 51. Can not be ignored.

  For this reason, in the positive electrode manufacturing unit 11 of the first manufacturing apparatus 10 </ b> L, the characteristics of the coating sagging of the strip electrode material 60 differ depending on the position in the width direction of the base material 600, and in the width direction of the base material 600. Depending on the position, the strip electrode material 60 is classified into the first to third strip electrode materials 60a to 60c. Then, the positive electrode manufacturing unit 11 of the first manufacturing apparatus 10 </ b> L manufactures the positive electrode 50 by intermittently transporting the strip electrode material 60 while calculating the feed amount according to the type of the strip electrode material 60. Hereinafter, the operation of the positive electrode manufacturing unit 11 of the first manufacturing apparatus 10L will be described in detail with reference to FIGS.

  FIG. 6 is a flowchart illustrating a procedure of an electrode manufacturing process performed by the positive electrode manufacturing unit 11 of the first manufacturing apparatus 10L. In the following, a process after the strip electrode material 60 cut by the positive electrode manufacturing unit 11 is replaced is shown.

  First, the positive electrode manufacturing unit 11 selects a data memory (step S101). More specifically, the calculation unit 17 of the positive electrode manufacturing unit 11 selects one memory corresponding to the band-shaped electrode material 60 after replacement from the first to third memories 181 to 183 included in the storage unit 18. To do. For example, when the third strip electrode material 60 c is newly set in the positive electrode manufacturing unit 11, the calculation unit 17 selects the third memory 183 from the first to third memories 181 to 183. As described above, the third memory 183 stores error information of the coating length of the active material layer 51 for the plurality of positive electrodes 50 manufactured in the past from the third strip electrode material 60c.

  Next, the positive electrode manufacturing unit 11 performs a feed amount calculation process (step S102). More specifically, the calculation unit 17 of the positive electrode manufacturing unit 11 calculates the feed amount of the strip electrode material 60 using the error information stored in one memory selected in the process shown in step S101.

  FIG. 7 is a flowchart illustrating the procedure of the feed amount calculation process executed by the calculation unit 17.

First, the calculating part 17 calculates the moving average value Z of an error (step S201). More specifically, the calculation unit 17 reads error information from the memory selected in the process shown in step S101 of FIG. 6 and, as shown in the following formula (1), the latest n errors e _{1 to} e The moving average value Z of _n is calculated.

  Here, n represents the number of error information used for calculating the moving average value Z, and is 15, for example. However, n is not limited to 15, and is appropriately changed according to the type of the strip electrode material 60 and the like.

Next, the computing unit 17 calculates the correction amount b _k (step S202). More specifically, the arithmetic unit 17, as shown in equation (2) below, multiplied by the predetermined gain K _I to the moving average value Z of error calculated in the process shown in step S201, the correction amount (first Correction value) b _k is calculated.

b _k = K _I × Z (2)
Here, the gain K _I is a value that allows for fine adjustment of the correction amount b _k, is changed according to the type of strip electrode material 60. For example, if the first and third strip electrode members 60a and 60c have a larger coating sagging than the second strip electrode member 60b, the gain of the first and third strip electrode members 60a and 60c is set to the second strip electrode member 60b. It is larger than the gain of 60b. Gain _{K I,} for example, be determined experimentally.

Next, the computing unit 17 determines whether or not the absolute value of the correction amount b _k is equal to or less than the reference value Ma (step S203). More specifically, as shown in the following equation (3), the calculation unit 17 determines that the absolute value of the correction amount b _k calculated in the process shown in step S202 is a predetermined reference value Ma (mm) (Ma is a positive value). It is determined whether or not it is less than or equal to.

| B _k | ≦ Ma (3)
Here, the reference value Ma is a value to eliminate outliers correction amount b _k, for example, it is changed according to the coating length of the standards of the active material layer 51.

When it is determined that the absolute value of the correction amount b _k is equal to or less than the reference value Ma (step S203: YES), the calculation unit 17 proceeds to the process of step S205.

On the other hand, when determining that the absolute value of the correction amount b _k is not equal to or less than the reference value Ma (step S203: NO), the calculation unit 17 replaces the correction amount b _k (step S204). More specifically, the arithmetic unit 17, if the correction value _{b k} is more than Ma, a correction value _{b k} is replaced by Ma, the correction value _{b k} is equal to or less than-Ma, a correction value _{b k} - Replace with Ma.

  Next, the calculating part 17 calculates the coating edge correction amount c (step S205). More specifically, the computing unit 17 first analyzes the first image data of the first camera 15 and ends 512 of the active material layer 51 provided on the strip electrode material 60 (see FIG. 2A). ) Is detected. Then, the calculation unit 17 calculates a coating end correction amount (second correction value) c as a correction amount for correcting the shift amount of the end portion 512 from the reference position.

Next, the arithmetic unit 17 calculates the feeding amount _{b z} (step S206). More specifically, the arithmetic unit 17, the coating end correction amount c which is calculated in the process shown in step S205, the correction amount b _k and a predetermined reference movement amount calculated in the process shown in step S202 or S204 (Feed The feed amount b _z of the strip electrode material 60 is calculated from the reference amount) b.

Figure 8 is a diagram for explaining a process of calculating a feed amount b _z of the strip electrode material 60.

The feed amount b _z of the strip electrode material 60 is calculated as the sum of the correction amount b _k , the coating end correction amount c, and the reference movement amount b as shown in the following equation (4).

b _z = b + c + b _k (4)
Here, as described above, the correction amount b _k is calculated by multiplying the gain K _I to the moving average value Z of the error of the coating length, each error e _i, as shown in the following equation (5), the coating It is calculated Engineering length reference value from (a target value) L _r by subtracting the measured value L _i of the coating length.

e _i = L _r −L _i (5)
As described above, according to the process shown in step S102 of FIG. 6, by using the error information stored in the memory selected in the process shown in step S101, the feed amount b _z of the strip electrode material 60 is calculated . More specifically, the error information of the coating length acquired for the positive electrode 50 manufactured from the same type of band electrode material 60 as the band electrode material 60 to be cut is used to obtain the band electrode material 60 to be cut. The feed amount _bz is calculated. For example, when the 3rd strip | belt-shaped electrode material 60c is set to the positive electrode manufacturing part 11, the error information of the coating length acquired about the some positive electrode 50 manufactured in the past about the 3rd strip | belt-shaped electrode material 60c is utilized. feed amount _{b z} of the third strip electrode material 60c is calculated.

Next, the positive electrode manufacturing unit 11 conveys the strip electrode material 60 (step S103). More specifically, the conveyance portion of the positive electrode manufacturing unit 11 (not shown), transports the third strip electrode material 60c only feed amount b _z calculated in the process shown in step S102.

  Next, the positive electrode manufacturing unit 11 cuts the strip electrode material 60 (step S104). More specifically, the cutting part (not shown) of the positive electrode manufacturing unit 11 uses the gap between the adjacent active material layers 51 at the end of the band electrode material 60 for the band electrode material 60 conveyed in the process shown in step S103. Die cutting is performed to cut out the positive electrode 50 from the strip-shaped electrode material 60.

As described above, according to the processing shown in steps S101 to S104 of FIG. 6, after replacement of the strip electrode material 60, one memory corresponding to the type of the strip electrode material 60 after replacement is selected and stored in the memory. feed amount b _z of the strip electrode material 60 is calculated by using the error information. Then, the strip electrode material 60 is intermittently conveyed by the calculated feed amount b _z, and the positive electrode 50 is cut out from the stopped strip electrode material 60.

  Next, the positive electrode manufacturing unit 11 measures the coating length of the active material layer 51 (step S105). More specifically, the calculation unit 17 of the positive electrode manufacturing unit 11 analyzes the second image data of the second camera 16, and as the coating length of the active material layer 51, the positive electrode cut out in the process shown in step S <b> 104. 50, the length of the other side portion 513 (see FIG. 2A) of the active material layer 51 is measured.

Next, the positive electrode manufacturing unit 11 calculates an error _{e i} of the coating length (step S106). More specifically, Nurikocho calculation unit 17 of the positive electrode production unit 11, as shown in the above equation (5), the length of the measurement value L _i of the active material layer 51 measured in the process shown in step S105 is subtracted from the reference value L _r, calculates an error e _i of the coating length.

Next, the positive electrode manufacturing unit 11 determines whether the absolute value of the error _{e i} is less than the allowable value Ea (step S107). More specifically, the calculation unit 17 of the positive electrode manufacturing unit 11, the absolute value of the error e _i calculated in the process shown in step S106, (the Ea positive number) a predetermined allowable value Ea (mm) or less Determine whether or not. Here, the allowable value Ea is a value for eliminating an abnormal value due to a measurement error or the like, and is changed according to the material of the active material layer 51, for example.

If it is determined that the absolute value of the error _{e i} is not less than the allowable value Ea (step S107: NO), the positive electrode manufacturing unit 11 uses the previous feed amount (step S108). More specifically, the calculation unit 17 of the positive electrode manufacturing unit 11 calculates the feed amount b _z used when the strip electrode material 60 was transported last time without calculating a new feed amount, after the strip electrode material 60. Used as feed amount.

On the other hand, if it is determined that the absolute value of the error _{e i} is less than the allowable value Ea (step S107: YES), the positive electrode manufacturing unit 11 performs the feed amount calculation process (step S109). More specifically, as shown in FIG. 9, the operation unit 17 of the positive electrode production unit 11 stores the error calculated in the process shown in step S106 in the corresponding memory, the latest including error e ₁ which is newly stored The moving average value Z of the _n errors e _{1 to} en is calculated, and the next feed amount b _z is calculated. Note that the feed amount calculation process shown in step S109 is the same as the process shown in step S102, and a detailed description thereof will be omitted.

  Next, the positive electrode manufacturing unit 11 conveys the strip electrode material 60 and cuts the strip electrode material 60 (steps S110 and S111). Since the processing shown in steps S110 to S111 is the same as the processing shown in steps S103 to S104, detailed description thereof is omitted.

As described above, according to the processing shown in steps S105 to S111 in FIG. 6, after the positive electrode 50 is cut out from the strip electrode material 60, the length of the active material layer 51 in the positive electrode 50 is measured, and the coating length is evaluated. Is done. Then, using the newly measured error in the length of the active material layer, the next feed amount b _{z of the} strip electrode material 60 is calculated.

  Next, the positive electrode manufacturing unit 11 determines whether or not the manufacturing of the positive electrode 50 is completed (step S112). More specifically, the calculation unit 17 of the positive electrode manufacturing unit 11 determines whether or not the manufacturing of the positive electrode 50 from the strip-shaped electrode material 60 to be cut is completed.

  When it is determined that the manufacture of the positive electrode 50 is not completed (step S112: NO), the positive electrode manufacturing unit 11 returns to the process of step S104. And the positive electrode manufacturing part 11 repeats the process after step S105 until manufacture of all the positive electrodes 50 is completed.

  On the other hand, when it is determined that the manufacture of the positive electrode 50 is completed (step S112: YES), the positive electrode manufacturing unit 11 executes the processes of steps S113 to S114 and ends the process. Since the processing shown in steps S113 to S114 is the same as the processing shown in steps S105 to S106, detailed description thereof is omitted.

As described above, according to the process of the flowchart shown in FIG. 6, when manufacturing the positive electrode 50 from the strip electrode material 60, the memory corresponding to the type of the strip electrode material 60 is selected, and the error stored in the selected memory is stored. using the information feed amount b _z of the strip electrode material 60 is calculated. Then, after the strip electrode material 60 is conveyed by the calculated feed amount b _z , the positive electrode 50 is cut out from the strip electrode material 60. Then, the length of the active material layer 51 in the positive electrode 50 is measured, and the coating length of the active material layer 51 is evaluated.

According to such a configuration, the correction amount b _k for correcting the error caused by the sagging of the active material layer 51 is reflected in the feed amount b _z of the strip electrode material 60. Therefore, even when the position in the width direction for detecting the end of the active material layer 51 of the strip electrode material 60 is different from the position in the width direction for measuring the length of the active material layer 51 of the positive electrode 50, The positive electrode 50 in which the measured value L _i of the length falls within the standard range can be manufactured. As a result, in the manufacturing process of the lithium ion secondary battery, the coating length Cpk (process capability index) of the active material layer 51 in the positive electrode 50 can be secured.

  FIG. 10 is a diagram for explaining the effect of the feed amount calculation process. FIG. 10 shows a case where the strip electrode material cut by the positive electrode manufacturing unit 11 of the first manufacturing apparatus 10L is changed from the first strip electrode material 60a to the third strip electrode material 60c.

  As shown in FIG. 10, when the strip electrode material 60 cut by the positive electrode manufacturing unit 11 is changed from the first strip electrode material 60a to the third strip electrode material 60c, the memory used for calculating the feed amount. Will also be changed. More specifically, coating is performed on the positive electrode 50 manufactured from the third strip electrode material 60c from the first memory 181 in which the error information of the coating length is stored for the positive electrode 50 manufactured from the first strip electrode material 60a. The memory is changed to the third memory 183 in which the long error information is stored. According to such a configuration, even if the strip electrode material 60 cut by the positive electrode manufacturing unit 11 is replaced, the positive electrode 50 in which the coating length of the active material layer 51 falls within the standard range can be manufactured.

  As described above, in the above-described embodiment, the position in the width direction for measuring the length of the active material layer 51 of the positive electrode 50 is different from the position in the width direction for detecting the end of the active material layer 51 of the strip electrode material 60. The operation of the positive electrode manufacturing unit 11 of the first manufacturing apparatus 10L has been described.

On the other hand, the position in the width direction for measuring the length of the active material layer 51 of the positive electrode 50 coincides with the position in the width direction for detecting the end of the active material layer 51 of the strip electrode material 60. The manufacturing unit 11 executes different feed amount calculation processes. For the positive electrode manufacturing unit 11 of the second manufacturing apparatus 10R, the coating sagging of the active material layer 51 of the strip electrode material 60 does not affect the length of the active material layer 51 to be measured. There is no need to consider sag. Thus, for the positive electrode preparation portion 11 of the second manufacturing apparatus 10R, the arithmetic unit 17, without calculating the correction amount b _k, calculating the feed rate from the coating end correction amount c and the reference movement amount b Can do.

  As described above, the described embodiment has the following effects.

(A) The feed amount b _z of the band-shaped electrode material 60 to be cut is obtained by using the error information of the coating length acquired for the positive electrode 50 manufactured from the band-shaped electrode material 60 having similar characteristics of the distortion of the active material layer. since but calculated, can be reflected in the coated amount sends sagging b _z of the active material layer 51 of the strip electrode material 60. As a result, even if the position in the width direction for measuring the length of the active material layer 51 of the positive electrode 50 is different from the position in the width direction for detecting the end of the active material layer 51 of the strip electrode material 60, the active material layer 51. The positive electrode 50 whose coating length falls within the standard range can be manufactured. Moreover, even when the strip electrode material 60 is replaced, the positive electrode 50 in which the coating length of the active material layer 51 is within the standard range can be manufactured.

(B) In order to calculate the feed amount b _z from the coating end correction amount c and the correction amount b _k , the positional deviation of the end portion of the active material layer 51 and the coating sagging of the active material layer 51 are set to the feed amount b _z . It can be reflected.

The gain K _I to be multiplied by the moving average value Z of (c) error is changed depending on the type of the strip electrode material 60 allows fine adjustment in accordance with the type of the strip electrode material 60.

(D) Since the reference value Ma of the correction amount b _k is changed according to the coating length standard of the active material layer 51, control according to the coating length standard becomes possible. Further, when the coating length standard is changed by changing the material or the plan, the reference value Ma can be changed.

(E) Since the moving average value Z of the error is calculated and the correction amount b _k is calculated from the latest n errors, the effect as a low-pass filter can be obtained, and it is possible to prevent a sensitive correction. . In addition, it is possible to selectively reflect only a new error in the correction amount b _k as compared with the error integral value.

(F) In order to measure the length of the cut active material layer 51 of the positive electrode 50 by conveying and cutting the strip electrode material 60 by the feed amount b _z reflecting the coating sagging of the active material layer 51, The coating length of the active material layer 51 can be evaluated while eliminating the influence of sagging.

(G) Since the error information acquired for the newly cut positive electrode 50 is stored in the storage unit 18 and the feed amount calculation process is repeatedly executed, the coating length error information for the latest positive electrode 50 is fed. while reflecting the b _z, it can be calculated following feed amount b _z.

  (H) Since the error tolerance Ea is changed according to the material of the active material layer 51, control according to the material of the active material layer 51 becomes possible. Further, when the material is changed, the allowable value Ea can be changed.

  In the above-described embodiment, the first camera 15 and the calculation unit 17 function as a detection unit that detects an end of the active material layer 51 of the strip electrode material 60. In addition, the second camera 16 and the calculation unit 17 function as a measurement unit that measures the length of the active material layer 51 of the positive electrode 50. Further, the calculation unit 17 also functions as a reading unit that reads error information from the memory.

  As described above, in the described embodiment, the electrode manufacturing method and the electrode manufacturing apparatus of the present invention have been described. However, it goes without saying that the present invention can be appropriately added, modified, and omitted by those skilled in the art within the scope of the technical idea.

  For example, in the above-described embodiment, the case where the strip electrode material is formed by dividing the base material of the strip electrode material into three has been described as an example. However, the strip-shaped electrode material obtained by dividing the base material into a plurality of parts is not limited to one formed by dividing the base material into three, for example, formed by dividing the base material into four Is done.

  In the above-described embodiment, in the positive electrode manufacturing unit of the first manufacturing apparatus, one end of one side of the active material layer provided on the strip electrode material is detected, while the other side of the active material layer of the positive electrode The length of the part was measured. However, the second position in the width direction for detecting the end portion of the active material layer and the first position in the width direction for measuring the length of the active material layer are not limited to the side portions of the active material layer. For example, for the length of the active material layer, the side portion on the tab side of the active material layer may be measured, while for the end portion of the active material layer, the center portion in the width direction of the active material layer may be detected. .

  In the above-described embodiment, the error information of the length of the active material layer is stored in three memories according to the position of the strip electrode material in the width direction of the base material for a plurality of positive electrodes manufactured from the strip electrode material. It was done. However, the information obtained by measuring the length of the active material layer of the positive electrode does not necessarily need to be stored in a plurality of memories in order to associate with the position of the strip electrode material in the width direction of the base material. Information obtained by measuring the length of the active material layer of the positive electrode may be stored in one memory in association with the position of the strip electrode material in the width direction of the base material.

  Moreover, in embodiment mentioned above, the case where a positive electrode was manufactured from a strip | belt-shaped electrode material was mentioned as an example, and was demonstrated. However, the present invention is also applicable when manufacturing a negative electrode from a strip electrode material.

10 Battery manufacturing system,
10L first manufacturing device,
10R second manufacturing device,
11 Positive electrode manufacturing department (electrode manufacturing equipment),
12 Packed positive electrode manufacturing department,
13 Negative electrode manufacturing department,
14 electrode lamination part,
15 1st camera (detection part),
16 Second camera,
17 Calculation unit (reading unit, detection unit),
18 storage unit,
20 Packed positive electrode,
30 negative electrode,
40 laminates,
50 positive electrode,
51,510 active material layer,
52 tabs,
60, 60a, 60b, 60c strip electrode material,
181, 182, 183 memory,
600 Base material for strip electrode material,
610 Metal foil.

Claims (9)

A band-shaped electrode material obtained by dividing a base material of a band-shaped electrode material provided with active material layers at predetermined intervals on a band-shaped metal foil in the width direction is cut while intermittently transporting the electrode from the band-shaped electrode material An electrode manufacturing method for manufacturing
The information obtained by measuring the length of the active material layer at the first position in the width direction of each electrode for the plurality of electrodes manufactured from the band-shaped electrode material is the band-shaped electrode material in the width direction of the base material. Is stored in the storage unit in association with the position of
For the strip-shaped electrode material to be cut, the step (a) of reading out the information associated with the same position as the position of the strip-shaped electrode material in the width direction of the base material from the storage unit;
A step (b) of detecting an end portion of the active material layer at a second position different from the first position in the width direction of the electrode for the active material layer provided on the band-shaped electrode material to be cut;
Based on the information read in the step (a) and the position information of the edge of the active material layer detected in the step (b), the feed amount of the strip-shaped electrode material to be cut is calculated. Step (c) to perform,
An electrode manufacturing method comprising: The information stored in the storage unit is information indicating an error from a target value of the length of the active material layer in the electrode,
The step (c)
A step (c1) of calculating a first correction value by calculating an average value of the errors from the information read in the step (a);
A step (c2) of calculating a second correction value from the position information of the end portion of the active material layer detected in the step (b);
The electrode manufacturing method according to claim 1, further comprising a step (c3) of calculating a feed amount of the strip-shaped electrode material to be cut from the first and second correction values and a reference value of the feed amount. In the step (c1), the first correction value is calculated by multiplying the average value of the errors by a gain,
The electrode manufacturing method according to claim 2, wherein the gain is changed according to a position of the strip electrode material in a width direction of the base material. When the first correction value is out of a predetermined range, the first correction value is replaced by one of the values at both ends of the range,
4. The electrode manufacturing method according to claim 2, wherein the values at both ends are changed according to a standard for the length of the active material layer in the electrode.   5. The electrode manufacturing method according to claim 2, wherein in the step (c1), the first correction value is calculated by calculating a moving average value of the error. A step (d) of transporting the band-shaped electrode material to be cut by the feed amount calculated in the step (c);
Cutting the strip electrode material transported in the step (d) and cutting the electrode from the strip electrode material (e);
A step (f) of measuring the length of the active material layer at the first position with respect to the electrode cut out in the step (e);
The electrode manufacturing method according to claim 1, further comprising:   The steps (a) to (c) are repeatedly performed after the information obtained by measuring the length of the active material layer in the step (f) is stored in the storage unit. Electrode manufacturing method. The information stored in the storage unit is information indicating an error from a target value of the length of the active material layer in the electrode,
When the absolute value of the error indicated by the information obtained by measuring the length of the active material layer in the step (f) is larger than a predetermined allowable value, the steps (a) to (c) are repeated. The previous feed amount is used as the next feed amount.
The electrode manufacturing method according to claim 7, wherein the allowable value is changed according to a material of the active material layer. A band-shaped electrode material obtained by dividing a base material of a band-shaped electrode material provided with active material layers at predetermined intervals on a band-shaped metal foil in the width direction is cut while intermittently transporting the electrode from the band-shaped electrode material An electrode manufacturing apparatus for manufacturing
The information obtained by measuring the length of the active material layer at the first position in the width direction of each electrode for the plurality of electrodes manufactured from the band-shaped electrode material is the band-shaped electrode material in the width direction of the base material. A storage unit stored in association with the position of
For the strip-shaped electrode material to be cut, a reading unit that reads from the storage unit the information associated with the same position as the position of the strip-shaped electrode material in the width direction of the base material;
For the active material layer provided on the band-shaped electrode material to be cut, a detection unit that detects an end of the active material layer at a second position different from the first position in the width direction of the electrode;
An arithmetic unit that calculates a feeding amount of the band-shaped electrode material to be cut based on the information read by the reading unit and the position information of the end of the active material layer detected by the detection unit; ,
An electrode manufacturing apparatus comprising: