JP2020024861A - Electrode plate elongation measurement apparatus and method using laser displacement meter - Google Patents

Abstract

To provide a measuring device and a measuring method that measure a difference in elongation between a coated portion and an uncoated portion of an electrode plate by using a laser beam.SOLUTION: The surface of a moving electrode plate is irradiated with a laser beam vertically, and the distance from a reference point is continuously measured, the amount of horizontal movement at the same time is obtained, and the outer length including the unevenness of an electrode plate is obtained from two data. The elongation ratio λ is obtained from the external length including the unevenness of the electrode plate and the horizontal movement amount, and is displayed.SELECTED DRAWING: Figure 1

Description

  The present invention relates to an apparatus and a method for measuring an elongation percentage including a wrinkle generated on an electrode plate surface by a laser displacement meter in a facility for manufacturing an electrode plate used for a battery.

  As shown in Patent Document 1, in order to accurately measure the elongation percentage of a steel sheet stretched by a rolling mill or bridle roll, rotary length measuring devices are attached to the entrance side and the exit side of the rolling mill, and the entrance and exit sides are measured. It is stated that elongation is determined from the difference in length.

Patent Literature 2 describes that light from a plurality of rod-shaped light sources is reflected on a steel plate surface, the reflected light is photographed by a camera, and steepness is obtained by comparison with a reference flat plate.

Patent Document 3 describes that minute irregularities on the surface of a cold-rolled steel sheet having a thickness of 0.4 mm or less are measured in detail using a laser displacement meter.

JP 2007-108036A JP 2011-099821 JP 2009-243907A

  A secondary battery made of lithium ion or the like is manufactured by applying an active material having a capability of transferring electrons to a surface of a metal foil such as aluminum or copper in a longitudinal direction. The electrode plate coated with the active material has an uncoated portion that becomes a current-carrying terminal portion when assembled as a battery. Since the electrode plate has a coated part and an uncoated part in the width direction in a strip shape, if the coated part and the uncoated part are pressed simultaneously with a press roll, the coated part is sandwiched between upper and lower press rolls The active material and the metal foil become thinner and stretch longer in the longitudinal direction. However, since the uncoated portion is thinner than the coated portion, the uncoated portion is sandwiched between the press rolls and is not pressed. Therefore, since the electrode plate does not extend in the longitudinal direction, the electrode plate extends in the width direction in the shape of a strip and coexists with a portion that does not extend and does not change in length. . It was difficult to measure the extent of the difference in elongation between the coated portion and the uncoated portion that caused wrinkles while the electrode plate was moving.

  The metal foil of the uncoated portion used for the electrode plate has a thickness of 20 μm or thinner. Therefore, if the means of Patent Document 1 is used, the metal foil on the surface of such a thin foil is used. If a rotary type length measuring device having a certain length is placed, the shape of the metal foil will change. If the length measuring device can be placed on the object to be measured, the external surface length can be accurately measured. However, the measurement conditions of the electrode plate are different from those of the rolled steel plate, and the length cannot be accurately measured using a length measuring device. With an electrode plate, accurate measurement is difficult unless it is a non-contact measuring instrument.

When the means of Patent Document 2 is used, the metal foil portion can reflect the light from the rod-shaped light source, but the coated portion on which the active material is applied has a color in which the active material is close to black and has a gloss. Because there is no light, the light from the rod-shaped light source cannot be reflected like a metal foil. Accurate elongation cannot be measured due to differences in light reflection conditions from the light source.

In the means of Patent Document 3, in a facility for rolling a thin steel sheet, the tension distribution in the width direction of the steel sheet is measured by a contact-type roll, and the produced steel sheet is placed on a surface plate to form a laser on the surface of the steel sheet. It is stated to measure with a distance meter. No mention is made of measuring the elongation of the unevenness on the surface of the steel sheet with a laser distance meter while the thin steel sheet moves while being rolled thinly.

  An object of the present invention is to provide a measuring device and a method using a laser displacement meter for accurately measuring the longitudinal extension length of an electrode plate used for a lithium ion battery or the like.

Specifically, the present invention relates to a measuring method for irradiating a laser beam from a laser transmitter arranged at a fixed position to a surface of an electrode plate moving in one direction to measure a distance to the surface of the electrode plate. The measured value A is the amount of change in the distance due to the unevenness of the surface of the electrode plate, and the measured value B is the length of movement of the electrode plate at the time when the change occurs. From the two measured values, the surface length including the irregularities of the electrode plate is calculated as a calculated value C, and the measured value B and the calculated value C are accumulated by a certain amount, and an equation of λ = (CB) / B is obtained. Is proposed as the elongation percentage of the electrode plate.

The present invention provides the method for measuring an elongation percentage of an electrode plate described above, wherein the coating of an electrode plate having a plurality of coated portions where an active material is coated on an electrode foil and an uncoated portion where the active material is not coated is performed. Laser oscillators are arranged at one or more locations of the processed part and at least one location of the uncoated part, and the distance to the surface of the electrode plate is continuously set in the moving direction of the electrode plate. The present invention proposes a method for measuring the elongation percentage of an electrode plate, which is characterized by performing the measurement.

According to the present invention, in the above-described method for measuring the elongation of an electrode plate, in a state where the electrode plate of the object to be measured moves horizontally on a guide roll, a laser beam is emitted perpendicularly to a moving direction of the electrode plate. The electrode plate and the laser oscillator are arranged, and the laser oscillator performs a distance measurement to the electrode plate 1000 times or more per second, and a device capable of simultaneously measuring a horizontal moving distance of the electrode plate is arranged. The present invention proposes an electrode plate elongation rate measuring device characterized by the above.

The present invention provides the method for measuring the elongation of an electrode plate described above, wherein a plurality of laser oscillators are arranged in the vertical width direction of the electrode plate, and the thickness of the electrode plate is continuously increased at a plurality of positions in the width direction of the electrode plate. Simultaneously with the measurement, the electrode plate elongation rate λ is obtained from the measurement data of the laser oscillator and the movement amount of the electrode plate, and a device capable of simultaneously measuring the elongation rate λ at a plurality of positions in the width direction of the electrode plate is arranged. Is proposed.

  The present invention relates to the above-described method for measuring the elongation of the electrode plate, wherein the length of the electrode plate from the reference point of the moving electrode plate to a position measured by the laser oscillator and the elongation of the electrode plate determined by the laser oscillator. The present invention proposes an electrode plate elongation rate measuring device having a device for storing a value indicating the state of the electrode plate in association with it.

  When the coated portion and the uncoated portion of the electrode plate are pressed and compressed by a roll press, a difference in elongation of the metal foil occurs. The coated and uncoated portions of the electrode plate are irradiated with a laser beam to determine the surface irregularities of the coated and uncoated portions from the reflected wave of the laser beam. The unevenness state is converted into data as the change value of the distance from the reference point, and the outer length including the unevenness of the electrode plate is calculated from the change data of the distance and the amount of movement of the electrode plate in the longitudinal direction, and from this result the electrode is obtained. Calculate and display the elongation λ of the plate. From the obtained elongation rate λ, the occurrence state of wrinkles of the electrode plate can be understood numerically, and can be used for control.

It is a figure showing an example of the whole system of an elongation generation state information acquisition device. It is a figure showing an example of a flow of measurement using a laser displacement meter. It is a figure which shows the whole outline of the roll press equipment which has the generation | occurrence | production state information acquisition apparatus. FIG. 3 is a diagram illustrating an example of an electrode plate in which an active material is applied in a stripe shape. It is sectional drawing of the electrode plate width direction. It is a figure showing an example of the rolling state of a metal strip by a roll. FIG. 4 is a plan view illustrating an example of wrinkles generated on an electrode plate. FIG. 7 is a sectional view of the electrode plates R, S, and T in FIG. 6. It is a figure showing an example which measures the distance to the surface of an electrode plate with a laser oscillator. It is a figure showing an example which measures unevenness of the surface of a moving electrode plate with a laser oscillator. It is a figure explaining the method of calculating from the movement length X of the electrode plate surface, and the laser oscillator measured value Y. It is a figure showing the example which displays an electrode board extension rate λ on a screen. It is a figure which shows an example which provided the uncoated part rolling apparatus in the roll press machine. It is a figure which shows one Example of an uncoated part rolling apparatus. FIG. 6 is a perspective view showing an example in which a laser oscillator for continuously measuring the thickness in the width direction of the electrode plate at a plurality of locations is arranged. It is the DD arrow view of FIG.14 (a). It is an example which shows the state which presses an electrode plate with a roll press machine. It is a figure showing an example of flatness of a metal strip. It is X sectional drawing of FIG. It is a figure which shows the flow of associating the elongation rate of an electrode plate with the distance from a reference point.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings.

  FIG. 1 is a diagram illustrating an entire system of an elongation occurrence state information acquisition device that measures an elongation length of an electrode plate 300 using a laser displacement meter 200 according to an embodiment of the present invention. FIG. 2 is a diagram illustrating an example of a measurement flow using a laser displacement meter.

The laser displacement meter 200 includes a laser oscillator 201, an arithmetic unit 204, and a rotation sensor 155. The elongation occurrence state information acquiring apparatus 1 calculates the measurement data sent from the laser oscillator 201 and the rotation sensor 155 by the arithmetic unit 204, and performs measurement according to the flow from S1 to S7 as shown in FIG. Details will be described in the following embodiments.

  FIG. 3 shows an overall outline of a roll press facility for pressing the electrode plate 300.

  On the entry side of the roll press machine 100, there is provided a coil unwinding machine 151 for mounting a coil before pressing in which an electrode plate 300 for a lithium ion battery is wound in a coil shape. A coil winder 152 that winds the pressed electrode plate 300 in a coil shape is provided. The heating roll 102 that can raise the temperature of the electrode plate 300 to about 150 degrees in order to more easily compress the electrode plate 300, the dancer roll 153 that controls the tension of the wound electrode plate 300 to a constant value, and supports the electrode plate 300 smoothly. A plurality of guide rolls 154 to be conveyed and a laser displacement meter 200 for measuring the surface shape of the electrode plate 300 with a laser beam 202 are arranged.

  The roll press 100 is provided with upper and lower press rolls 101, and an electrode plate 300 (FIG. 4B) in which an active material 302 is coated on the surface of the metal foil 301 is sandwiched between the press rolls 101 and passed while being pressed. Then, compression processing of the active material 302 is performed. The roll press 100 is provided with a bearing box 103 for holding the upper and lower press rolls 101 and a housing 104 for supporting the pressing force and holding the bearing box 103 from the outside.

  FIG. 4 is a diagram illustrating an example of an electrode plate 300 in which an active material is applied in a stripe shape.

  4A shows a plane of the electrode plate 300, and FIG. 4B shows a cross section of the electrode plate 300 in the width direction.

  The electrode plate 300 is exemplified by a lithium ion battery. As shown in FIG. 4, a stripe-shaped active material 302 is applied to the surface of a band-shaped metal foil 301 (such as an aluminum foil or a copper foil). Since the uncoated portion 301 becomes a current-carrying terminal portion in the process of assembling the battery, the active material 302 is not coated, and the metal foil 301 is exposed. In the cross-sectional view of the electrode plate 300 shown in FIG. 4B, the thickness is described with a thickness. However, the thickness of the metal foil 301 is about 10 to 20 μm, and the thickness of the coating section 302 is different from the upper and lower active materials. The entire thickness of the metal foil 301 is 200 to 250 microns before pressing. When the electrode plate 300 is roll-pressed by the upper and lower press rolls 101, the active material is compressed in the coating portion 302, and the coating portion 302 is thinned to about 100 to 140 μm. The uncoated portions 301a and 301b do not contact the upper and lower press rolls 101 and are not stretched because no press load is applied.

  FIG. 5 is a diagram illustrating an example of a rolling state of a metal strip by a rolling roll.

  Normally, even if a thin metal strip material 500 (hereinafter referred to as a metal strip material) is rolled, surface unevenness caused by a difference in elongation becomes a problem, and flatness is evaluated using a means of steepness. In the electrode plate 300, a portion to be pressed and a portion not to be pressed occur due to a difference in thickness between the coated portion 302 and the uncoated portion 301, and a large difference in elongation occurs. The surface of the electrode plate 300 has surface irregularities different from those of the metal strip material. Hereinafter, the difference between the rolling of the metal strip and the roll press of the electrode plate 300 will be described in detail.

  FIG. 15 is an example showing a state in which the electrode plate is pressed by a roll press.

  FIG. 16A is a diagram illustrating an example of the flatness of a metal strip.

  FIG. 16B is a cross-sectional view of FIG.

  In the case of a metal strip, as shown in FIG. 5, the upper and lower cylindrical rolls 501 are rolled so that a uniform rolling force (linear pressure) is generated in the width direction of the metal strip 500 on the material to be rolled. The pressing force between the rolls 501 is controlled. However, even if a uniform rolling force is applied in the width direction, the material to be rolled is subject to delicate differences such as changes in the roll diameter caused by the temperature difference in the axial direction of the roll and deflection of the roll shaft caused by the rolling force. A difference in elongation occurs at the center portion or at the end portion, and the difference in elongation appears as surface irregularities. In the rolling, as a means for comparing the flatness, as shown in FIG. 16, the surface irregularities in the longitudinal direction of the steel sheet are measured, and the peak height (H) per pitch (P) from the peaks and valleys of the irregularities is measured. Is calculated to obtain the steepness. The steepness is determined by the equation of H / P.

  A change in the roll diameter or a change in the amount of deflection gradually occurs due to a change in conditions such as a rolling time.

The surface irregularities of the metal strip after rolling are a certain length (100 m or more) and the pitch of the peaks is almost the same, and the height of the peaks remains the same. The magnitude of the surface irregularities of the metal strip can be evaluated by the steepness. The pitch between the peaks is also affected by the plate thickness. When the thickness of the metal strip is 0.3 mm, the pitch between the peaks is 300 to 600 mm. Therefore, even if the surface unevenness is measured at a measurement interval of about 10 mm, the measurement accuracy of the steepness is not significantly affected.

As shown in FIG. 15, when the electrode plate 300 is pressed by the roll press machine 100, the coating portion 302 of the electrode plate 300 is formed by pressing the upper and lower press rolls so that a uniform rolling force (linear pressure) is generated in the same manner as the strip plate material. The pressing force between 101 is controlled, and elongation occurs in the longitudinal direction after pressing. However, since the uncoated portion 301 does not contact the upper and lower press rolls 101 at all, no elongation occurs due to rolling. Therefore, a large difference in elongation occurs at the boundary between the coated portion 302 and the uncoated portion 301.

  FIG. 6 is a plan view showing an example of wrinkles generated on the electrode plate.

  As shown in FIG. 6, due to a large difference in elongation, different surface irregularities and wrinkles are generated between the coated portion 302 and the uncoated portion 301. The reason why the surface unevenness of the metal strip 500 and the electrode plate 300 occurs is greatly different.

Further, the coating portion 302 of the electrode plate 300 has a three-layer structure (sandwich structure) because active materials are bonded to the upper and lower surfaces of the metal foil 301. Even if the same difference in elongation occurs in the electrode plate 300, the surface unevenness does not have a uniform waveform like a sine wave, but has an uneven waveform due to differences in hardness of the active material and drying conditions. Because of such a difference, in the electrode plate 300, the concept of steepness used when evaluating the elongation state (flatness) in the rolling of the metal strip 500 cannot be used.

  FIG. 7 is a sectional view of the electrode plates R, S, and T of FIG.

  In FIG. 7, the fact that the surface irregularities greatly differ between the coated portion 302 and the uncoated portion 301 is shown as typical cross-sectional shapes of the R, S, and T cross sections of the electrode plate 300.

  As described above, the surface of the electrode plate 300 has a difference in surface unevenness at a position in the width direction due to the influence of the uncoated portion 301. Therefore, as a means for judging the size of the surface irregularities of the electrode plate 300, the surface external length generated by the roll press is accurately measured and calculated, and the length of the actual length of the electrode plate is not affected by the surface irregularities. A means for evaluating the size of the surface unevenness is suitable.

At this time, the metal foil 301 in the uncoated portion is thin and soft, so that the pitch of the surface irregularities is about 6 to 10 mm, which is shorter than that of the coated portion. The pitch between peaks is about 1/50 of that of a metal strip. Means for accurately measuring the surface external length of the electrode plate 300 having different surface irregularities while moving will be described below.

After being pressed by the roll press machine 100, the electrode plate 300 moves horizontally while being held by guide rolls 154 as shown in FIG. Since the electrode plate 300 moves horizontally in close contact with the guide roll 154, the moving speed of the electrode plate 300 is measured from the number of rotations of the guide roll 154 or the like. Further, a dancer roll 153 that controls the tension of the electrode plate 300 functions so that the electrode plate 300 moves with a given tension, and the electrode plate 300 moves between the guide rolls 154 without vibration or the like. I do.

  FIG. 8 is a diagram illustrating an example in which the distance to the surface of the electrode plate is measured by a laser oscillator.

  The laser oscillator 201 is mounted at a position where the laser beam 202 is irradiated perpendicular to the moving direction of the electrode plate 300. The laser beam 202 emitted from the laser oscillator 201 is reflected by the electrode plate 300 and received by the laser oscillator 201 again. The position where the laser oscillator 201 is fixed is the reference position 203. As shown in FIG. 8, the distance Y1 until the laser beam 202 emitted from the laser oscillator 201 is reflected on the surface of the electrode plate 300 is measured.

Since the electrode plate 300 moves from the entrance side to the exit side at a constant speed, as shown in FIG. 8, the laser beam 201 emitted from the laser oscillator hits the surface of the electrode plate 300 and is reflected at a high speed according to the movement of the electrode plate 300, The distance from the reference position 203 to the uneven surface of the electrode plate 300 is continuously measured each time the electrode plate moves horizontally by Y2, Y3, and Y4 and X.

  FIG. 9 is a diagram illustrating an example in which the unevenness of the moving electrode plate surface is measured by a laser oscillator.

FIG. 9 is displayed on the assumption that the electrode plate 300 is fixed and the laser oscillator 201 has horizontally moved the position of the reference position 203 in order to make the movement of FIG. 8 easier to understand.

  FIG. 10 is a view for explaining a method of calculating from the movement length X of the electrode plate surface and the laser oscillator measured value Y.

In FIG. 10, the outer length of the surface of the electrode plate 300 having irregularities is obtained from the measured value (Y) of the distance from the reference point 203 to the surface of the electrode plate 300 by the laser oscillator 201 and the amount of movement (X) of the electrode plate 300 in the horizontal direction. The method for calculating by calculation will be described. When the distance measurement value Y1 changes to Y2 when the electrode plate 300 moves by X in the horizontal direction, the unevenness change amount of the electrode plate 300 is Y1-Y2. By assuming that the curve of the outer shape of the electrode plate 300 at this time is a straight line, the length (C) of the long side of the right triangle becomes the outer shape length of the unevenness of the electrode plate 300. Therefore, the length C1 of the side is calculated by Equation 1 according to the Pythagorean theorem.

Equation 1

  In order to reduce the deviation between the actual outer curve and the approximate outer length obtained by calculation, the time for measuring Y is made as short as possible, the moving amount of X is made extremely small, and the number of divisions is increased. The deviation between the length and the actual outer length approaches zero as much as possible.

In the case of the electrode plate 300 moving at 120 m / min, the movement amount X moves 2 m per second in order to measure the change amount Y every 1 mm, so that 2000 measurements and calculations by the laser oscillator 201 per second are required. It is necessary to dispose the laser displacement meter 200 that can perform such high-speed measurement and calculation. Alternatively, when measurement with higher precision is required, the deviation between the actual outer length and the calculated value can be made as close to zero as possible by reducing the moving speed of the electrode plate 300.

Next, the necessity of measuring the change amount Y of the movement amount X every 1 mm will be described. Since the material of the metal foil 301 used for the electrode plate 300 is thin and aluminum foil, copper foil, or the like is used, the period length of the irregularities is extremely shorter than that of the steel plate. In the case of a 20-micron thick aluminum foil used for the uncoated portion 301 of the electrode plate 300, the pitch of the surface irregularities is about 6 to 10 mm.

In addition, the "method for measuring the flatness of copper and copper alloy plates" defined by the Japan Copper and Brass Association technical standard specifies as follows. The target copper material has a thickness of 50 to 500 microns and a width of 15 to 700 mm. This thin copper plate is cut out and placed on a measuring table of 500 mm or more, and it is required to measure the amount of change in the uneven shape displayed using the laser displacement meter 200 in units of 1 micron. At the same time, the longitudinal direction requires measurement every 1 mm.

As described above, in order to accurately measure the asperity shape displayed by the thin metal foil and to determine the amount of elongation, it is necessary to digitize the change in the height direction every 1 mm in the longitudinal direction. As shown in FIG. 16, the Japan Copper and Brass Association finds the height difference (H) and pitch (P) of the unevenness from the cut sample material, and indicates the state of elongation by steepness.

  In a roll press machine, it is necessary to grasp the elongation state of the electrode plate 300 during production, so that the elongation length can be measured under the same conditions as when cutting out and measuring, so that the surface unevenness of the electrode plate 300 is measured every 1 mm in the longitudinal direction. It is necessary to measure the change in height. When the electrode plate 300 moves at a high speed, the speed becomes 120 m / min, so to measure the distance from the reference to the surface of the electrode plate 300 at a pitch of 1 mm, perform the distance measurement 2000 times per second with the laser displacement meter 200, It needs to be calculated. In the case of a low speed, the moving speed of the electrode plate 300 is about 60 m / min. Therefore, in order to perform the same measurement at a pitch of 1 mm, distance measurement 1000 times per second is required.

The method of displaying the elongation state with the steepness assumes that the concavo-convex shape to be displayed continues in the same state. It is difficult to assume that the electrode plate 300 has the active material 302 adhered to both sides, and that the concavo-convex shape to be displayed continues in the same state. Therefore, as described above, the elongation length of the electrode plate 300 is obtained and quantified by using the method of calculating the external length of the uneven shape to be displayed.

The total value obtained by adding n pieces of C1, C2, C3, and C4 calculated by the calculation device 204 according to Equation 1 is C. The obtained C value is the outer length including the uneven shape to be displayed. If the distance B of the electrode plate 300 is calculated as B = n × X, the moving distance B is obtained. If the elongation is large, the outer length becomes longer, so the C value becomes larger. If there is no elongation, the outer length C value and the moving length B value become the same. The elongation rate λ of the electrode plate 300 is obtained by Expression 2. The elongation ratio λ represents the ratio of the elongation to the reference length B.

Equation 2

As the value of the elongation λ is closer to 0%, the unevenness of the electrode plate 300 is smaller. It can be determined that the electrode plate 300 has no difference in elongation. When comparing the state of occurrence of the difference in elongation, the elongation rate CB including the actual unevenness can be obtained as the elongation rate λ per unit length by dividing the elongation length CB by the moving length B. By comparing a plurality of λs in the width direction, the overall elongation difference (wrinkle) of the electrode plate 300 can be evaluated. If the λ value is compared at any location in the longitudinal direction, it is possible to evaluate the state of occurrence of differential elongation (wrinkle) under the same conditions. As described above, it is possible to obtain information on the state of wrinkles occurring on the electrode plate 300.

The electrode plate 300 has a band shape with a coated portion 302 coated with the active material 302 in the width direction and an uncoated portion 301 not coated in the width direction. Only the metal foil 301 of the electrode plate 300 is stretched. In order to compare the magnitude of the difference in elongation generated between the coated part 302 and the uncoated part 301 by the elongation rate λ, a laser oscillator 201 as shown in FIG. . At least one laser oscillator 201 is also arranged in the uncoated portion 301 at the same position in the width direction. In particular, since a large difference in elongation (wrinkle) does not occur near the boundary between the coated portion 302 and the uncoated portion 301, the laser oscillator is applied to each of the coated portion 302 and the uncoated portion 301 of the electrode plate 300 near the boundary. 201 is arranged and the elongation rate λ is obtained and displayed.

Using the obtained elongation ratios λ of the coated portion 302 and the uncoated portion 301 of the electrode plate 300, which side of the coated portion 302 or the uncoated portion 301 has a difference in elongation (wrinkle). to decide. As a criterion, a difference in elongation (wrinkle) occurs more toward a numerical value having a larger elongation rate λ. In the roll press machine 100 having equipment for controlling the elongation of the electrode plate 300, the control function is used to control the elongation rate λ to be smaller.

Specific means for reducing the difference in elongation (wrinkles) between the coated portion 302 and the uncoated portion 301 will be described below. Since a large difference in elongation occurs between the coated portion 302 and the uncoated portion 301 of the electrode plate 300 along the boundary line, a different control means is required from that in a case where the spread occurs over a wide range such as rolling of a metal plate. .

  FIG. 12 is a diagram illustrating an example in which an uncoated portion rolling device is provided in a roll press.

  FIG. 13 is a diagram illustrating an example of an uncoated portion rolling device.

  A specific example will be described with reference to FIGS.

  An uncoated portion rolling device 400 capable of rolling only the metal foil of the uncoated portion 301 is arranged on the entry side of the press roll 101. The uncoated portion rolling device 400 is disposed in the roll press machine 100 and has a diameter difference in the roll axis direction so that the cylindrical upper roll 401 and the uncoated portion 301 can be pressed only. It comprises a push-up device 403 that holds a bearing 404 holding the 402 and an uncoated portion 301 between upper and lower rolls 401 and 402 and generates a target pressing force.

When a difference in elongation occurs between the coated part 302 and the uncoated part 301 of the electrode plate 300, the force of the pusher 403 is controlled so as to reduce the difference in elongation, and the pressing force between the upper and lower rolls 401, 402 is adjusted. . When the difference in elongation decreases to a target range, the pressing force between the upper and lower rolls 401 and 402 is controlled to be constant. In the embodiment, the upper and lower rolls are arranged to roll the uncoated portion 301. However, the present invention is not limited to this mechanism. Has a mechanism capable of controlling the pressing force of the first and second portions, thereby making it possible to correct the difference in elongation between the coated portion 302 and the uncoated portion 301. The means for reducing the difference in elongation between the coated part 302 and the uncoated part 301 of the electrode plate 300 is not limited to the above-described means.
The overall system and measurement flow of the laser displacement meter 200 will be described with reference to FIGS. The electrode plate 300 moves on the guide roll 154 by the rotation of the press roll 101, and the measurement data Y measured by the laser oscillator 201 provided on the exit side of the press roll 101 is sent to an arithmetic unit 204 such as a sequencer. The pulse from the rotation sensor 155 attached to the guide roll 154 is sent to the arithmetic unit 204, and the required movement amount X in Expression 1 is obtained from the diameter of the guide roll 154 and the rotation angle of the rotation sensor 155. A high-speed operation is performed by the arithmetic unit 204 from the transmitted X and Y data, and the obtained elongation rate λ is displayed on the screen display 205. Although it is a short calculation flow, it is necessary to measure 1000 to 2000 times per second and display the calculation instantaneously in order to accurately determine the external length. The method of measuring the movement amount X is not limited to the rotation sensor 155.

Further, a reference point is provided in the longitudinal direction of the electrode plate 300 so that the position measured by the laser oscillator 201 can be stored as a distance from the reference point. Specifically, an opening is provided in the electrode plate 300, and an optical sensor 155 for recognizing light passing through the opening is provided. When the opening passes, a signal is sent from the optical sensor 156 to the arithmetic unit 204, and the signal is recognized as a reference point. The rotation sensor 155 attached to the guide roll 154 calculates the distance of the electrode plate 300 from the reference point, and recognizes the position of the electrode plate 300 in the longitudinal direction. The method of recognizing the reference point is not limited to the recognition of light passing through the opening, and the connection point between the preceding electrode plate 300 and the rear electrode plate 300 can be used as the reference point. The elongation rate λ of the electrode plate 300 measured by the above method is associated with the distance in the longitudinal direction from the reference point and stored as data in the storage device of the arithmetic unit 204 or the like. As shown in FIG. 17, the position in the longitudinal direction of the electrode plate 300 and the elongation data are recorded in the arithmetic unit 204 in association with the flow from S1 to S8.

When a quality problem occurs in the next process, the elongation data of the electrode plate 300 can be used. The stored elongation rate is not limited to λ calculated by Equation 2, but the height (H) of the hill caused by the elongation as shown in FIG. 16 may be stored in the arithmetic unit 204 as the elongation value. It is.

FIG. 11 is a diagram illustrating an example in which the electrode plate elongation rate λ is displayed on a display screen.
When performing the roll pressing work of the electrode plate 300 having the wide coating portion 302, the entire width of the coating portion 302 and the laser oscillator 201 are arranged in the uncoated portion 301, and the elongation λ is measured and calculated, respectively. A display as shown in FIG. 11 is displayed on the screen display 205 so that the operator can easily determine the extension state in the 300 width direction. The measured position is displayed on the horizontal axis, and the measurement result is displayed on the vertical axis of the elongation percentage λ. The occurrence state of the difference in elongation (wrinkle) can be determined at a glance from the elongation rate λ of the electrode plate 300 in the width direction. The screen display 205 allows the electrode plate 300 to move and continuously display the elongation rate λ that changes one after another.

In the above description, it is described that an external length including irregularities on the surface of the electrode plate 300 is obtained in a roll press facility, and an elongation ratio λ is calculated and displayed from a reference length. This measuring device and method are not limited to the roll press equipment, but the active material coating apparatus or the drying apparatus upstream of the roll press equipment may be used to apply the active material 302 to the metal foil 301 in the same manner as the roll press equipment. Since drying is performed, a difference in elongation easily occurs due to heat or the like. The elongation occurrence state information acquisition apparatus and method capable of displaying the state of the difference in elongation generated on the electrode plate 300 by the elongation ratio λ are effective.

  FIG. 14A is a perspective view showing an example in which laser oscillators for continuously measuring the thickness of the electrode plate in the width direction at a plurality of locations are arranged.

  FIG. 14B is a front view of FIG.

It is also possible to simultaneously measure the thickness of the electrode plate 300 and measure the elongation λ. As shown in FIG. 14A, there is a thickness gauge that measures the thickness of the electrode plate 300 in the width direction with the laser displacement meter 200. In this thickness gauge, laser oscillators 201 are arranged above and below an electrode plate 300, and adjustment is performed so that the upper and lower laser beams 202 are aligned as shown in FIG. The thickness of the electrode plate 300 is obtained by subtracting the distance Y from the upper and lower reference positions 203 to the electrode plate 300 measured by the upper and lower laser oscillators 201. If a plurality of laser oscillators 201 are vertically arranged in the width direction of the electrode plate 300, the thickness difference in the width direction of the electrode plate 300 can be measured at the same time. This thickness measurement method has already been implemented. Further, by taking into account the distance data Y change amount from the laser oscillator 201 and the movement length X in the movement direction of the electrode plate 300 described above, the outer peripheral length C of the electrode plate 300 is obtained. The elongation rate λ in the longitudinal direction can also be continuously measured at a plurality of points in the width direction.

  DESCRIPTION OF SYMBOLS 1 ... Elongation generation state information acquisition apparatus, 100 ... Roll press machine, 101 ... Press roll, 102 ... Heating roll, 104 ... Housing, 151 ... Coil unwinder, 152 ... Coil unwinder, 153 ... Dancer roll, 154 ... Guide roll, 155 rotation sensor, 156 optical sensor, 200 laser displacement meter, 201 laser oscillator, 202 laser beam, 203 reference position, 204 arithmetic unit, 205 screen display, 300 electrode plate, 301 ... Metal foil (uncoated part), 302 ... Active material (coated part) 400 ... Uncoated part rolling device, 401 ... upper roll, 402 ... lower roll, 403 ... pusher 500 ... metal strip 501 Rolling roll

Claims (5)

In a strip-shaped electrode plate which is a battery material in which an active material is coated on a thin metal foil surface, the electrode plate has a coated portion coated with an active material and an uncoated portion formed of a metal foil in a strip shape. A laser beam is emitted from a laser oscillator to the electrode plate, a distance from a reference point to the surface of the electrode plate is measured, and an amount of change in distance from the reference point to the surface of the electrode plate after a predetermined time is A, Let B be the length at which the laser beam has moved for a certain time in the direction perpendicular to the laser beam,
The external length of the electrode plate calculated from the measured values A and B is C, the C value is accumulated, and the external length of the electrode plate is obtained.
An elongation occurrence state information acquisition device, wherein at least one device for obtaining the external length is disposed in each of a coated portion and an uncoated portion. 2. The elongation occurrence state information acquiring device according to claim 1, wherein the measured value B and the calculated value C are accumulated from 200 to 1000, and an equation of λ = {(CB) / B} × 100 is obtained. The elongation occurrence state information acquisition device, wherein λ obtained by the above is the elongation percentage of the electrode plate.   3. The elongation occurrence state information acquisition device according to claim 1, wherein the elongation rate λ of the electrode plate is such that an electrode foil is coated with an active material coated with an active material and the active material is coated. An elongation occurrence state information acquiring device, wherein a roll press device is controlled so that a difference is reduced in an uncoated portion. In a strip-shaped electrode plate which is a battery material in which an active material is applied to a thin metal foil surface moving on a production line, the electrode plate is an uncoated material including a coated portion coated with an active material and a metal foil. Has a portion in a strip shape, emits a laser beam from a laser oscillator to the electrode plate, measures the distance from the reference point to the electrode plate surface, the amount of distance change from the reference point to the electrode plate surface after a certain time. A, the length of the electrode plate moved at a certain time in a direction perpendicular to the laser beam as B,
Let C be the length of the outer shape of the electrode plate obtained by calculation from the measured values A and B, accumulate the C value, obtain the outer length of the electrode plate, and obtain wrinkle occurrence state information generated on the electrode plate. A method for acquiring elongation occurrence state information, characterized in that:   A laser beam is radiated from a laser oscillator to the surface of the electrode plate serving as a battery material moving on the production line, and the distance from a reference point to the surface of the electrode plate is measured to measure the distance to the object to be measured by measuring the reflection distance of the laser beam. An electrode plate distance measuring device and a device for measuring a distance from a reference position in the longitudinal direction of the electrode plate to a laser beam measuring position, and the data measured and calculated by the electrode plate distance measuring device in the moving direction of the outer shape of the electrode plate. An elongation occurrence state information acquisition device, which is stored as a value indicating an elongation state of the electrode plate in association with a distance from a reference position in a longitudinal direction of the electrode plate to a measurement position.

Images