WO2023228446A1 - Winding device - Google Patents

Abstract

Provided is a winding device that can more accurately detect positional deviation of the distal end of an electrode sheet, and that can reduce production costs, improve production efficiency, etc. This winding device 10 comprises: electrode sheet supply mechanisms 31, 41 that supply electrode sheets 4, 5 to a winding core 12 side; a mark provided to the outer peripheral surface of the winding core 12; sensors 14a, 14b, 15a, 15b that detect information related to the positions of the distal ends of the electrode sheets 4, 5 relative to the mark; a determination unit 92 that determines the quality related to the positions of the distal ends on the basis of the detected information. The sensors 14a, 14b, 15a, 15b perform the detection of the information from when the electrode sheets 4, 5 are supplied to the winding core 12 side to when the electrode sheets 4, 5 are wound one circumference. When the quality is determined to be defective by the determination unit 92, a winding control device 91 stops the winding of the electrode sheets 4, 5 before the winding of the electrode sheets 4, 5 is completed.

Description

winding device

The present invention relates to a winding device for obtaining a winding element built into, for example, a secondary battery or the like.

For example, in a wound element used in a secondary battery such as a lithium ion battery, a positive electrode sheet coated with a positive electrode active material and a negative electrode sheet coated with a negative electrode active material are separated by a separator sheet made of an insulating material. It is manufactured by winding the wires in an overlapping state.

As a winding device for manufacturing a wound element, one equipped with a rotatable winding core and a supply mechanism that supplies an electrode sheet to the winding core is known. The supply mechanism has a gripping part (chuck) that can grip the electrode sheet, and the gripping part moves toward the winding core while gripping the electrode sheet, thereby transferring the electrode sheet to the winding core. supply

By the way, when the electrode sheet is supplied to the winding core, the electrode sheet slips against the grip, or when the winding core starts rotating, the electrode sheet slips against the separator sheet, causing the electrode sheet to slip along the circumferential direction of the winding core. There may be a shift in the position of the tip. When such a positional shift occurs, the mutual positional relationship of each electrode sheet and separator sheet becomes inappropriate, and there is a possibility that a decrease in battery capacity or an internal short circuit may occur. That is, misalignment of the tip end of the electrode sheet may have a significant effect on battery performance. Therefore, it is necessary to prevent the wound element with such positional deviation from being sent to the subsequent process.

Here, conventionally, a winding device has been proposed that is configured to be able to determine whether or not the mutual positional relationship of each electrode sheet and separator sheet is appropriate in a completed winding element (for example, (See Reference 1). To explain this winding device in more detail, this winding device includes an encoder that comes into contact with the electrode sheet and measures the length (feed amount) of each electrode sheet fed out to the winding core side, and an encoder that measures the length (feed amount) of each electrode sheet sent out to the winding core side, and a sensor that detects the coating start portion. When the coating start point is detected by the sensor, the encoder starts measuring the feed amount, and when the winding core has rotated enough to wrap each electrode sheet, the amount of each electrode sheet measured by the encoder starts to be measured. The feed amount is compared. That is, the feed amount of the positive electrode sheet and the feed amount of the negative electrode sheet are compared. Based on the results of this comparison, the quality of the completed wound element is determined, and wound elements determined to be defective are not sent to subsequent processes.

Japanese Patent Application Publication No. 11-67262

By the way, according to the technique described in Patent Document 1, it is possible to eventually detect the presence or absence of positional deviation at the tip of the electrode sheet, but this technique ultimately It merely detects the relative positional relationship of the electrode sheets. Therefore, with this technique, it is not possible to accurately detect the absolute positional deviation of the tip of the electrode sheet, and there is a possibility that a defective wound element with a positional deviation may be erroneously determined to be a good item. For example, if the same degree of slippage occurs in both electrode sheets, the obtained wound element is actually a defective product with misalignment, but with the above technique, the obtained wound element is mistakenly turned into a good product. It is determined that Therefore, in the above technique, there is a risk that defective wound elements are sent to the subsequent process, resulting in unnecessary work in the subsequent process.

In addition, with the above technology, if the electrode sheet slips with respect to the encoder, the measured feed amount will differ from the actual feed amount, which may result in insufficient accuracy in determining the quality of the wound element. .

Furthermore, in the above technique, regardless of whether the wound element that is finally obtained is a good product or a defective product, the winding of the electrode sheet, etc. by the winding core is continued until the winding is completed. Therefore, a large amount of material (electrode sheets, etc.) is wasted in manufacturing defective wound elements, which may lead to an increase in production costs. Furthermore, since it takes time to manufacture defective wound elements, production efficiency decreases.

The present invention has been made in view of the above circumstances, and its purpose is to more accurately detect the positional deviation of the tip of the electrode sheet along the circumferential direction of the winding core, and to reduce production costs. It is an object of the present invention to provide a winding device that can improve productivity and production efficiency.

Hereinafter, each means suitable for solving the above objective will be explained in sections. Note that effects specific to the corresponding means will be added as necessary.

Means 1. A belt-shaped electrode sheet having an active material on the surface and a belt-shaped separator sheet made of an insulating material are supplied to a rotatable winding core, and the rotation of the winding core causes the electrode sheet and the separator sheet to separate. A winding device that winds while overlapping,
Winding control means for controlling rotation of the winding core;
an electrode sheet supply means for supplying the electrode sheet to the winding core side with the tip end of the electrode sheet as the leading edge;
a mark provided on the outer peripheral surface of the winding core;
Tip position detection means for detecting information regarding the position of the tip with respect to the mark along the circumferential direction of the winding core;
Based on the information detected by the tip position detection means, the quality of the position of the tip of the electrode sheet along the circumferential direction of the winding core is determined before and/or during winding of the electrode sheet. and a determination means for determining,
The tip position detection means detects the information during a period from when the electrode sheet is supplied to the winding core side by the electrode sheet supply means until the electrode sheet is wound for one round. It is composed of
The winding control means is configured to be able to control the winding core so that winding of the electrode sheet is stopped before winding of the electrode sheet is completed when the determination means determines that the winding core is defective. A winding device characterized by:

According to the above means 1, the tip position detection means detects the information regarding the position of the tip of the electrode sheet with respect to the mark provided on the winding core, and the determining means determines the tip of the electrode sheet based on the information. The quality of the position is determined. In this way, since the position of the tip of the electrode sheet is directly detected using the mark, it is possible to more accurately detect the positional shift of the tip of the electrode sheet, which in turn improves the accuracy of pass/fail judgment. . For example, if the same degree of slippage occurs in both electrode sheets, the positions of the tips of both electrode sheets with respect to the marks will be inappropriate, so it can be determined that the sheet is defective.

Furthermore, it is possible to more reliably prevent defective wound elements in which the tip end of the electrode sheet is misaligned from being sent to the subsequent process. Therefore, it is possible to effectively suppress the occurrence of wasteful work in the post-process.

Furthermore, according to the above means 1, the information is detected by the tip position detection means after the electrode sheet is supplied to the winding core side until the electrode sheet is wound for one round, The determining means performs a quality determination based on the detected information before and/or during winding of the electrode sheet. If the electrode sheet is determined to be defective, the winding control means stops the winding of the electrode sheet before the winding of the electrode sheet is completed. Therefore, waste of materials (electrode sheets, etc.) can be reduced as much as possible, and production costs can be reduced. In addition, it is possible to more reliably prevent the electrode sheet from continuing to be wound even though the tip of the electrode sheet is misaligned, and it is possible to quickly move on to manufacturing the next wound element. . Therefore, production efficiency can be improved.

Means 2. Means characterized in that the mark is formed by providing a colored portion in a color different from each color of the electrode sheet and the outer peripheral surface of the winding core on at least the bottom surface of a recess provided on the outer peripheral surface of the winding core. 1. The winding device according to 1.

According to the above-mentioned means 2, since the colored portion has a color different from each color of the outer peripheral surface of the electrode sheet and the winding core, information regarding the position of the tip of the electrode sheet with respect to the mark can be detected with higher accuracy. . As a result, pass/fail determination can be made more accurately.

Furthermore, since the colored portion is located on the bottom surface of the recess, it becomes difficult for the separator sheet etc. to come into contact with the colored portion. Therefore, it is possible to more reliably prevent the colored portion from peeling off or chipping due to repeated manufacturing of the wound element, and it is possible to accurately detect the information over a long period of time. Furthermore, since the frequency of mark-related maintenance and parts replacement can be reduced, it is possible to more effectively reduce production costs and improve production efficiency.

In order to further improve the accuracy of detecting the information, the color of the colored part should be the opposite color of the electrode sheet (particularly the part used for detecting the information) on the hue wheel, or a color close to the opposite color. It is preferable.

Means 3. The winding device according to means 2, wherein the recess is provided at a position of the outer circumferential surface of the winding core that is away from a surface on which the separator sheet is wound.

According to the above means 3, the recess is not provided on the surface of the outer circumferential surface of the winding core around which the separator sheet is wound. Therefore, it is possible to prevent the inner peripheral portion of the winding element from entering the recess. Thereby, the winding element can be more easily removed from the winding core. Furthermore, when the winding element is removed from the winding core, it is possible to more reliably prevent the winding element from being damaged by the concave portion, thereby improving the quality of the winding element.

Means 4. In the means 2 or 3, the tip position detection means is configured to detect, as the information, information regarding whether or not the mark is hidden by the electrode sheet. Winding device as described.

According to the above means 4, the information regarding the position of the tip of the electrode sheet with respect to the mark is not the distance between the mark and the tip, but information about whether or not the mark is hidden by the electrode sheet. Detected. Therefore, information can be detected more easily, and accuracy regarding quality determination can be further improved.

Means 5. The tip position detection means includes a color sensor capable of detecting the color of the colored portion, and depending on whether or not the color of the colored portion is detected by the color sensor, the position of the mark is determined by the electrode sheet. The winding device according to means 4, characterized in that the winding device is configured to detect information regarding whether or not the winding device is in a hidden state.

According to the above means 5, information regarding whether or not the mark is hidden by the electrode sheet is detected based on whether or not the color of the colored portion is detected by the color sensor. Therefore, the tip position detection means can be realized at a lower cost, and the costs associated with manufacturing, maintenance, etc. of the winding device can be reduced.

Means 6. The tip position detection means is configured to detect the information between when the electrode sheet is supplied to the winding core side by the electrode sheet supplying means and until rotation of the winding core is started. The winding device according to means 1, characterized in that:

According to the above means 6, the information is detected before the rotation of the winding core is started. Therefore, the quality determination regarding the positional deviation can be made at the very early stage of the process of winding the electrode sheet or the like. Thereby, waste of materials (electrode sheets, etc.) can be further reduced, and production costs can be further reduced. Furthermore, if the tip of the electrode sheet is misaligned, it is possible to quickly move on to manufacturing the next wound element, thereby further improving production efficiency.

Furthermore, according to the above means 6, it is possible to detect the positional deviation caused by the slippage of the electrode sheet with respect to the electrode sheet supply means when the electrode sheet is supplied to the winding core. Therefore, when it is determined that the product is defective, it becomes easier to identify the cause of the positional deviation, and the effort and time required to deal with the occurrence of defective products (inspection, etc.) can be reduced.

Means 7. The tip position detection means is characterized in that it is configured to detect the information between the time when the core starts rotating and the time when the electrode sheet is wound for one revolution. The winding device according to means 1.

According to the above means 7, not only the positional deviation caused by the slippage of the electrode sheet with respect to the electrode sheet supplying means when supplying the electrode sheet to the winding core, but also the slippage of the electrode sheet with respect to the separator sheet at the time of starting rotation of the winding core. It is also possible to detect the positional deviation caused by. Therefore, the accuracy of the quality determination regarding the positional deviation can be further improved.

Furthermore, by employing both of the above means 6 and 7, the cause of the positional shift can be identified more easily. That is, if it is determined to be defective based on the information detected before the rotation of the winding core starts, the cause of the positional deviation is the electrode sheet supplying means at the time of supplying the electrode sheet to the winding core. This can be identified as the slippage of the electrode sheet against the surface. In addition, while it was determined to be good based on the information detected before the rotation of the winding core started, it was determined that the electrode sheet was good after the rotation of the winding core started until the electrode sheet was wound one round. If it is determined to be defective based on the detected information, it can be determined that the cause of the positional shift is slippage of the electrode sheet with respect to the separator sheet at the start of rotation of the winding core. By making it easier to identify the cause, it is possible to further reduce the effort and time required to respond to the occurrence of defective products (inspections, etc.).

Means 8. As the electrode sheets, a band-shaped positive electrode sheet having a positive electrode active material on its surface and a band-shaped negative electrode sheet having a negative electrode active material on its surface are supplied to the winding core, and as the winding core rotates, the positive electrode sheet The electrode sheet and the negative electrode sheet are configured to be rolled while being overlapped,
As the mark, a predetermined positive electrode mark and a predetermined negative electrode mark are provided separately,
The tip position detection means includes information regarding the position of the tip of the positive electrode sheet with respect to the positive electrode mark along the circumferential direction of the winding core, and information regarding the position of the tip of the positive electrode sheet with respect to the negative electrode mark along the circumferential direction of the winding core. Detecting information regarding the position of the tip of the negative electrode sheet,
The determining means determines the quality of the positions of the respective leading ends of the positive electrode sheet and the negative electrode sheet along the circumferential direction of the winding core, based on the information detected by the leading end position detecting means. The winding device according to means 1, characterized in that it is configured as follows.

According to the above means 8, since a separate mark is used for each electrode sheet, information regarding the position of each tip of each electrode sheet can be detected with higher accuracy. As a result, it is possible to more accurately determine the quality of the position of the tip of each electrode sheet.

Note that the technical matters related to the above-mentioned means may be combined as appropriate. For example, the technical matters related to the above-mentioned means 2 may be combined with the technical matters related to the above-mentioned means 6.

FIG. 1 is a schematic perspective view showing a schematic configuration of a battery element. FIG. 2 is a schematic plan view showing a schematic configuration of a positive electrode sheet. FIG. 2 is a schematic plan view showing a schematic configuration of a negative electrode sheet. It is a schematic block diagram of a winding device. FIG. 3 is a schematic perspective view showing a winding core and the like. It is a flowchart of a winding process. FIG. 3 is a schematic configuration diagram of a winding section and the like when supplying an electrode sheet to the winding core side. FIG. 6 is an explanatory diagram for explaining the case where the first positive electrode sensor detects information related to the position of the tip of the positive electrode sheet with respect to the positive electrode mark. FIG. 7 is an explanatory diagram for explaining a case where information related to the position of the tip of the negative electrode sheet with respect to the negative electrode mark is detected by the first negative electrode sensor. FIG. 7 is an explanatory diagram for explaining the case where the second positive electrode sensor detects information related to the position of the tip of the positive electrode sheet with respect to the positive electrode mark. FIG. 7 is an explanatory diagram for explaining the case where information related to the position of the tip of the negative electrode sheet with respect to the negative electrode mark is detected by the second negative electrode sensor. FIG. 3 is a schematic configuration diagram of a winding section and the like when cutting an electrode sheet. FIG. 3 is a schematic perspective view showing an example of an electrode sheet arranged in a normal positional relationship with respect to a mark. FIG. 2 is a schematic perspective view showing an example of an electrode sheet arranged in an abnormal positional relationship with respect to a mark. FIG. 7 is a schematic perspective view showing marks and the like in another embodiment. FIG. 7 is a schematic perspective view showing marks and the like in another embodiment. In another embodiment, it is a schematic plan view showing the schematic structure of a positive electrode sheet having a molded tab. In another embodiment, it is a schematic plan view showing the schematic structure of a negative electrode sheet having a molded tab. FIG. 7 is a schematic plan view showing a schematic configuration of a positive electrode sheet having a welding tab in another embodiment. In another embodiment, it is a schematic plan view showing the schematic structure of a negative electrode sheet having a welding tab.

Hereinafter, one embodiment will be described with reference to the drawings. First, the configuration of a lithium ion battery element as a "wound element" obtained by a winding device will be explained.

As shown in FIG. 1, a lithium ion battery element 1 (hereinafter simply referred to as "battery element 1") has a positive electrode sheet 4 and a negative electrode sheet 5 stacked on top of each other with two separator sheets 2 and 3 in between. It is manufactured by winding it in a state. In this embodiment, the positive electrode sheet 4 and the negative electrode sheet 5 each correspond to an "electrode sheet". Note that instead of the two separator sheets 2 and 3, a single folded separator sheet may be used. Furthermore, hereinafter, for convenience of explanation, the separator sheets 2 and 3 and the electrode sheets 4 and 5 may be referred to as "various sheets 2 to 5."

The separator sheets 2 and 3 are each in the form of a band having the same width, and are made of an insulator such as polypropylene (PP) to prevent the different electrode sheets 4 and 5 from coming into contact with each other and causing a short circuit. It is made up of.

The electrode sheets 4 and 5 are made of thin metal sheets and are wider than the separator sheets 2 and 3. Furthermore, active materials are applied to both the front and back surfaces of the electrode sheets 4 and 5. For example, an aluminum foil sheet is used as the positive electrode sheet 4, and a positive electrode active material (for example, lithium manganate particles, etc.) is coated on both the front and back surfaces. For example, a copper foil sheet is used as the negative electrode sheet 5, and a negative electrode active material (for example, activated carbon, etc.) is coated on both the front and back surfaces. Ion exchange between the positive electrode sheet 4 and the negative electrode sheet 5 can be performed via the active material. More specifically, during charging, ions move from the positive electrode sheet 4 side to the negative electrode sheet 5 side, and during discharging, ions move from the negative electrode sheet 5 side to the positive electrode sheet 4 side.

In addition, in this embodiment, the lengths of both electrode sheets 4 and 5 constituting one battery element 1 are each set to a constant predetermined value. In this embodiment, the length of the negative electrode sheet 5 for one element is slightly larger than the length of the positive electrode sheet 4 for one element in order to more reliably cover the positive electrode sheet 4 with the negative electrode sheet 5. has been done.

In addition, as shown in FIGS. 2 and 3, on both the front and back surfaces of each electrode sheet 4, 5, there are active material coated areas 4a, 5a (areas with a dotted pattern) coated with the active material, and Active material non-coated portions 4b and 5b to which active material is not coated are provided. The active material-uncoated portion 4b of the positive electrode sheet 4 is provided at one end in the width direction of the positive electrode sheet 4, and protrudes from one end edge in the width direction of the separator sheets 2 and 3 (see FIG. 1). On the other hand, the active material-uncoated portion 5b of the negative electrode sheet 5 is provided on the other end side in the width direction of the negative electrode sheet 5, and protrudes from the other end edge in the width direction of the separator sheets 2 and 3 (see FIG. 1). ). These active material non-applied portions 4b, 5b extend continuously along the longitudinal direction of the electrode sheets 4, 5, and function as electrode tabs, respectively.

When obtaining a lithium ion battery, the wound battery element 1 is placed in a metal cylindrical battery container (case) (not shown), and the electrode tabs of the positive electrode sheet 4 (not coated with active material) are portion 4b) and the electrode tab of the negative electrode sheet 5 (active material non-coated portion 5b) are each put together. Then, the electrode tabs of the collected positive electrode sheets 4 are connected to the positive electrode terminal parts (not shown), and the electrode tabs of the negative electrode sheets 5 which are also collected are connected to the negative electrode terminal parts (not shown), and both ends A lithium ion battery can be obtained by providing the child parts so as to close the openings at both ends of the battery container.

Next, the winding device 10 for manufacturing the battery element 1 will be explained. As shown in FIG. 4, the winding device 10 includes a winding section 11 for winding various sheets 2 to 5, and a positive electrode sheet supply mechanism 31 for supplying the positive electrode sheet 4 to the winding section 11. , a negative electrode sheet supply mechanism 41 for supplying the negative electrode sheet 5 to the winding section 11, separator supply mechanisms 51 and 61 for supplying the separator sheets 2 and 3 to the winding section 11, respectively, and a winding A control device 91 is provided. Note that various mechanisms in the winding device 10, such as the winding section 11 and each supply mechanism 31, 41, 51, 61, are configured to be operated and controlled by a winding control device 91. In this embodiment, each of the electrode sheet supply mechanisms 31 and 41 constitutes an "electrode sheet supply means", and the winding control device 91 constitutes a "winding control means".

The positive electrode sheet supply mechanism 31 includes a positive electrode sheet raw material 32 formed by winding the positive electrode sheet 4 into a roll. The positive electrode sheet original fabric 32 is rotatably supported, and the positive electrode sheet 4 is drawn out from there as appropriate.

Further, the positive electrode sheet supply mechanism 31 includes a sheet insertion mechanism 71, a sheet cutting cutter 72, and a tension applying mechanism 73.

The sheet insertion mechanism 71 is for supplying the positive electrode sheet 4 to the winding section 11, and is arranged at an approach position approaching the winding section 11 and a position away from the winding section 11 along the conveyance path of the positive electrode sheet 4. It is configured to be movable to a retracted position. The sheet insertion mechanism 71 is disposed at a position sandwiching the transport path of the positive electrode sheet 4, and includes two gripping parts 71a and 71b that can grip the positive electrode sheet 4. The gripping parts 71a and 71b are configured to be able to be opened and closed by a drive means (not shown), and the positive electrode sheet 4 can be switched between gripping and releasing by opening and closing the gripping parts 71a and 71b. Then, with the positive electrode sheet 4 being gripped by the gripping parts 71a and 71b, the sheet insertion mechanism 71 moves from the retracted position to the approach position, so that the positive electrode sheet 4 is The electrode sheet 4 can be supplied to the winding core 12 side of the winding section 11, which will be described later.

The sheet cutting cutter 72 is for cutting the positive electrode sheet 4. The cutting of the positive electrode sheet 4 is performed while the positive electrode sheet 4 is held by the sheet insertion mechanism 71. Further, the sheet cutting cutter 72 can be separated from the transport path of the positive electrode sheet 4 so as not to obstruct the supply of the positive electrode sheet 4 by the sheet insertion mechanism 71.

The tension applying mechanism 73 is for applying tension to the positive electrode sheet 4, and includes a plurality of rollers (for example, dancer rollers, etc.). In this embodiment, a constant tension is always applied to the positive electrode sheet 4 by the tension applying mechanism 73.

The negative electrode sheet supply mechanism 41 includes, on its most upstream side, a negative electrode sheet raw material 42 in which the negative electrode sheet 5 is wound into a roll. The negative electrode sheet original fabric 42 is rotatably supported, and the negative electrode sheet 5 is drawn out from there as appropriate.

In addition, in the middle of the conveyance path of the negative electrode sheet 5 from the negative electrode sheet raw material 42 to the winding section 11, a sheet insertion mechanism 71, a sheet cutting cutter 72, and a tension applying mechanism are provided, similarly to the conveyance path of the positive electrode sheet 4. A mechanism 73 is provided. These are similar to those provided on the transport path of the positive electrode sheet 4, except that they function for the negative electrode sheet 5.

On the other hand, the separator supply mechanisms 51 and 61 are equipped with separator original fabrics 52 and 62 formed by winding separator sheets 2 and 3 into rolls, respectively. The separator original fabrics 52, 62 are supported so as to be freely rotatable, and the separator sheets 2, 3 are drawn out from there as appropriate.

Furthermore, the separator supply mechanisms 51 and 61 are equipped with a tension applying mechanism 73, similar to the electrode sheet supply mechanisms 31 and 41. This is similar to that provided in the positive electrode sheet supply mechanism 31, except that it functions for the separator sheets 2 and 3.

Next, the configuration of the winding portion 11 will be explained. The winding unit 11 includes a winding core 12 that is rotatable about its own central axis as a rotation axis, and a touch roller 13 that can be pressed against the outer circumferential surface of the winding core 12 . In addition, although not shown, a separator cutter for cutting the separator sheets 2, 3, a fixing tape, etc. are attached to the winding portion 11 to secure the terminal ends of the separator sheets 2, 3, as in the conventional case. A tape sticking mechanism and a removal mechanism for removing the battery element 1 and the like after winding is completed from the winding core 12 are provided.

The winding core 12 is for winding up the various sheets 2 to 5 on its own outer peripheral side, and is configured to be rotatable about its own central axis as a rotation axis by a drive mechanism (not shown). The amount of rotation of the winding core 12 can be determined by an encoder (not shown), and information regarding the amount of rotation is inputted to the winding control device 91 from the encoder.

As shown in FIG. 5, the winding core 12 includes a first core piece 121 and a second core piece 122. Further, a slit 123 extending in a direction perpendicular to the rotation axis of the winding core 12 is formed between each core piece 121 and 122. Furthermore, a chuck mechanism (not shown) for clamping the separator sheets 2 and 3 inserted through the slit 123 is provided at a portion of the winding core 12 where the slit 123 is formed.

In this embodiment, the winding core 12 is arranged such that its outer peripheral surface, that is, the region around which the various sheets 2 to 5 are wound, has a circular shape in a cross section perpendicular to its central axis (rotation axis). However, the shape of the outer peripheral surface of the winding core 13 (14) may be changed as appropriate. For example, the outer circumferential surface of the winding core 12 may have an elliptical cross-section, an elliptical cross-section, or the like.

Furthermore, a positive electrode mark 4x and a negative electrode mark 5x are provided on the outer peripheral surface of the winding core 12. In this embodiment, the positive electrode mark 4x and the negative electrode mark 5x each correspond to a "mark."

The positive electrode mark 4x is a reference mark for detecting information regarding the position of the tip of the positive electrode sheet 4 along the circumferential direction of the winding core 12. The positive electrode mark 4x is located at one end in the width direction of the winding core 12, that is, at the active material non-coated portion 4b that protrudes from one end edge in the width direction of the separator sheets 2 and 3 when the various sheets 2 to 5 are wound around the winding core 12. (The electrode tab of the positive electrode sheet 4) is provided corresponding to the side where it is arranged. The positive electrode mark 4x is formed by providing a colored portion 4y of a color different from the colors of the outer peripheral surfaces of the positive electrode sheet 4 and the winding core 12, at least on the bottom surface of a recess 124 provided on the outer peripheral surface of the winding core 12.

The negative electrode mark 5x is a reference mark for detecting information regarding the position of the tip of the negative electrode sheet 5 along the circumferential direction of the winding core 12. The negative electrode mark 5x is the active material-uncoated part that protrudes from the other end of the winding core 12 in the width direction, that is, the other end of the separator sheets 2 and 3 in the width direction when the various sheets 2 to 5 are wound around the winding core 12. 5b (electrode tab of the negative electrode sheet 5) is provided corresponding to the side where it is arranged. The negative electrode mark 5x is formed by providing a colored portion 5y of a color different from the colors of the outer peripheral surfaces of the negative electrode sheet 5 and the winding core 12, at least on the bottom surface of a recess 125 provided on the outer peripheral surface of the winding core 12.

The color of the colored portion 4y of the positive electrode mark 4x is preferably the opposite color of the positive electrode sheet 4 (particularly the active material non-coated portion 4b) on the color wheel, or a color close to the opposite color. Further, the color of the colored portion 5y in the negative electrode mark 5x is preferably the opposite color to the color of the negative electrode sheet 5 (particularly the active material non-coated portion 5b) on the hue wheel, or a color close to the opposite color. For example, when the negative electrode sheet 5 is made of copper foil, the color of the colored portion 5y of the negative electrode mark 5x is the opposite color of the copper foil (close to red) or a color close to the opposite color. It is preferable to use green or blue.

Further, each mark 4x, 5x is provided at a different position along the circumferential direction of the winding core 12. This is because the leading end of the negative electrode sheet 5 is placed further forward in the rotational direction of the winding core 12 than the leading end of the positive electrode sheet 4 in order to more reliably cover the positive electrode sheet 4 with the negative electrode sheet 5. This is to respond.

Furthermore, each mark 4x, 5x (each colored part 4y, 5y) has a certain width (for example, a width of several mm or more) along the circumferential direction of the winding core 12. Further, the depth of the recesses 124 and 125 is relatively small (for example, about 1 mm). The colored portions 4y and 5y are provided, for example, by pouring paint into the recesses 124 and 125, or by subjecting the bottom surfaces of the recesses 124 and 125 to a surface treatment such as plating.

In addition, each of the recesses 124 and 125 (each of the marks 4x and 5x) is provided at a position of the outer circumferential surface of the winding core 12 away from the surface around which the separator sheets 2 and 3 are wound. In other words, each of the recesses 124 and 125 (each of the marks 4x and 5x) is provided at a position that does not overlap with the separator sheets 2 and 3 wound around the winding core 12. Therefore, when winding of the various sheets 2 to 5 by the winding core 12 is completed and the battery element 1 is obtained, the various sheets 2 to 5 of the obtained battery element 1 are in the tightly wound portion. The peripheral portion does not enter into the recesses 124, 125 and does not come into contact with the marks 4x, 5x.

Returning to FIG. 4, the touch roller 13 is configured to be freely rotatable, and is configured to be movable between a contact position where it can make contact with the winding core 12 and a separate position where it is spaced apart from the winding core 12. . When the touch roller 13 is in the contact position, the touch roller 13 is urged toward the central axis of the winding core 12 by a predetermined urging means (not shown).

Furthermore, the winding unit 11 detects information regarding the position of the tip of the positive electrode sheet 4 with respect to the positive electrode mark 4x along the circumferential direction of the winding core 12 (hereinafter sometimes simply referred to as "positive electrode position information"). A first positive electrode sensor 14a and a second positive electrode sensor 14b are provided for this purpose. The winding unit 11 also detects information regarding the position of the tip of the negative electrode sheet 5 with respect to the negative electrode mark 5x along the circumferential direction of the winding core 12 (hereinafter sometimes simply referred to as "negative electrode position information"). A first negative electrode sensor 15a and a second negative electrode sensor 15b are provided for this purpose. In this embodiment, each sensor 14a, 14b, 15a, 15b constitutes a "tip position detection means".

Each positive electrode sensor 14a, 14b is provided so as to face the outer circumferential surface of one end in the width direction of the winding core 12 on which the positive electrode mark 4x is provided. Each positive electrode sensor 14a, 14b emits white light (red light, green light, blue light) toward one end in the width direction of the winding core 12, and detects the color of the projected object from the amount of light reflected. It is a color sensor. Each positive electrode sensor 14a, 14b determines whether the positive electrode mark 4x is hidden by the positive electrode sheet 4 based on whether or not the color of the colored portion 4y of the positive electrode mark 4x is detected. Detect about. In this embodiment, information regarding whether or not the positive electrode mark 4x is hidden by the positive electrode sheet 4 is used as the positive electrode position information.

Further, when the positive electrode sheet 4 is supplied to the winding core 12 by the positive electrode sheet supply mechanism 31, the first positive electrode sensor 14a is located at a position opposite to the planned position of the tip end of the positive electrode sheet 4. It is set in. The first positive electrode sensor 14a receives positive electrode position information after the positive electrode sheet supply mechanism 31 supplies the positive electrode sheet 4 to the winding core 12 side and until the winding core 12 starts rotating. Detection is now possible. That is, the first positive electrode sensor 14a detects information about the initial position of the tip of the positive electrode sheet 4.

On the other hand, the second positive electrode sensor 14b is provided at a position shifted by a predetermined angle (for example, 180°) or more along the circumferential direction of the winding core 12 with respect to the first positive electrode sensor 14a. The second positive electrode sensor 14b detects the positive electrode position information after the positive electrode sheet 4 is supplied and the winding core 12 starts rotating until the positive electrode sheet 4 is wound for one turn. It is designed to do this. In this embodiment, the second positive electrode sensor 14b is provided at a position shifted by 180 degrees or more along the circumferential direction of the winding core 12 with respect to the first positive electrode sensor 14a. Therefore, the second positive electrode sensor 14b detects the positive electrode position information when the positive electrode sheet 4 is wound up by more than half a turn but less than one turn.

Each negative electrode sensor 15a, 15b is provided so as to face the outer circumferential surface of the other end in the width direction of the winding core 12 on which the negative electrode mark 5x is provided. Each negative electrode sensor 15a, 15b is a color sensor that projects white light toward the other end in the width direction of the winding core 12 and detects the color of the object to be emitted from the amount of light reflected. Each negative electrode sensor 15a, 15b determines whether the negative electrode mark 5x is hidden by the negative electrode sheet 5 based on whether the color of the colored portion 5y of the negative electrode mark 5x is detected. Detect about. In this embodiment, information regarding whether or not the negative electrode mark 5x is hidden by the negative electrode sheet 5 is used as the negative electrode position information.

Furthermore, when the negative electrode sheet 5 is supplied to the winding core 12 by the negative electrode sheet supply mechanism 41, the first negative electrode sensor 15a is located at a position opposite to the planned arrangement position of the tip end of the negative electrode sheet 5. It is set in. The first negative electrode sensor 15a receives negative electrode position information from the time when the negative electrode sheet 5 is supplied to the winding core 12 by the negative electrode sheet supply mechanism 41 until the rotation of the winding core 12 is started. Detection is now possible. That is, the first negative electrode sensor 15a is configured to detect information about the initial position of the tip of the negative electrode sheet 5.

On the other hand, the second negative electrode sensor 15b is provided at a position shifted by a predetermined angle (for example, 180°) or more along the circumferential direction of the winding core 12 with respect to the first negative electrode sensor 15a. The second negative electrode sensor 15b detects the negative electrode position information after the negative electrode sheet 5 is supplied and the rotation of the winding core 12 is started until the negative electrode sheet 5 is wound for one round. It is designed to do this. In this embodiment, the second negative electrode sensor 15b is provided at a position shifted by 180 degrees or more along the circumferential direction of the winding core 12 with respect to the first negative electrode sensor 15a. Therefore, the second negative electrode sensor 15b detects the negative electrode position information when the negative electrode sheet 5 is wound more than half a turn but less than one turn.

By the sensors 14a, 14b, 15a, 15b configured as described above, the electrode sheets 4, 5 are supplied to the winding core 12 side by the electrode sheet supply mechanisms 31, 41, and then the electrode sheets 4, 5 are rotated once. Until the winding is completed, positive electrode position information is detected twice and negative electrode position information is detected twice. The detected positive electrode position information and negative electrode position information are sent to the winding control device 91.

Note that if excessive slippage of the electrode sheets 4, 5 with respect to the gripping parts 71a, 71b occurs when the electrode sheets 4, 5 are supplied to the winding core 12 side, the initial position of the tip end of the electrode sheets 4, 5 may be 4 and 5 to the upstream side in the conveyance direction (backward side in the rotational direction of the winding core 12), and the positive electrode position information and negative electrode position information detected for the first time indicate an abnormality. Further, when the electrode sheets 4 and 5 excessively slip with respect to the separator sheets 2 and 3 as the winding core 12 starts rotating, the positions of the tips of the electrode sheets 4 and 5 may be shifted to the upstream side in the conveyance direction (in the rotation direction). The positive electrode position information and the negative electrode position information detected for the second time indicate an abnormality.

The winding control device 91 includes a CPU as a calculation means, a ROM for storing various programs, a RAM for temporarily storing various data, a hard disk for long-term storage of data, and the like. The winding control device 91 controls the supply of the electrode sheets 4 and 5 to the winding core 12 side, the rotation of the winding core 12, and the like.

Further, the winding control device 91 includes a determination section 92. In this embodiment, the determining unit 92 constitutes a "determining means".

The determination unit 92 determines whether the electrode sheets 4, 5 are aligned in the circumferential direction of the winding core 12 before and during winding, based on the positive electrode position information and the negative electrode position information detected by the sensors 14a, 14b, 15a, and 15b. The quality of the positions of the tips of the electrode sheets 4 and 5 is determined.

More specifically, the determination unit 92 determines the quality of the position of the tip of the positive electrode sheet 4, based on the positive electrode position information detected by the first positive electrode sensor 14a, before winding up the positive electrode sheet 4. Further, the determination unit 92 determines whether the position of the tip of the positive electrode sheet 4 is good or bad while the positive electrode sheet 4 is being wound up, based on the positive electrode position information detected by the second positive electrode sensor 14b.

Further, the determining unit 92 determines whether the position of the tip of the negative electrode sheet 5 is good or bad based on the negative electrode position information detected by the first negative electrode sensor 15a before winding up the negative electrode sheet 5. Further, the determination unit 92 determines whether the position of the tip of the negative electrode sheet 5 is good or bad while the negative electrode sheet 5 is being wound up, based on the negative electrode position information detected by the second negative electrode sensor 15b.

The quality judgment in the judgment section 92 is based on whether the marks 4x, 5x are hidden by the electrode sheets 4, 5, that is, the colors of the colored sections 4y, 5y are detected by the sensors 14a, 14b, 15a, 15b. This is done based on whether or not it was done. More specifically, if the colors of the colored parts 4y, 5y are not detected by the sensors 14a, 14b, 15a, 15b and the marks 4x, 5x are covered with the electrode sheets 4, 5, the determination unit 92 determines that the electrodes It is determined that the positions of the leading ends of the sheets 4 and 5 are "good". On the other hand, if the colors of the colored parts 4y, 5y are detected by the sensors 14a, 14b, 15a, 15b, and at least a portion of the marks 4x, 5x are not covered by the electrode sheets 4, 5, the determining unit 92 determines that It is determined that the positions of the tips of the electrode sheets 4 and 5 are "defective." The determination result by the determination unit 92 is stored in a predetermined storage device (not shown).

Further, the winding control device 91 is configured to stop the winding of the electrode sheets 4, 5 before the winding of the electrode sheets 4, 5 is completed when the determination unit 92 determines that the electrode sheets 4, 5 are "defective". The operation of the winding core 12 is controlled. That is, when the determination unit 92 determines that the various sheets 2 to 5 are "defective" based on the positive electrode position information or the negative electrode position information detected by the first sensors 14a and 15a, the winding control device 91 If the determining unit 92 determines that the electrode sheet is "defective" before winding, the operation of the winding core 12 is controlled so that the winding of the electrode sheets 4 and 5, which is normally performed, is not started. Further, the winding control device 91 determines that the various sheets 2 to 5 are "defective" by the determination unit 92 based on the positive electrode position information or the negative electrode position information detected by the second sensors 14b and 15b. If the determining unit 92 determines that the winding core 12 is "defective" during winding, the operation of the winding core 12 is controlled so that the rotation of the winding core 12 is immediately stopped.

Next, a method for manufacturing the battery element 1 (winding process of various sheets 2 to 5) using the winding device 10 configured as described above will be explained with reference to FIG. 6.

First, in step S11, the leading ends of the separator sheets 2 and 3 held by a separator holding means (not shown) are newly guided between the slits 123 of the winding core 12. Next, the separator sheets 2 and 3 placed in the slit 123 are clamped by the chuck mechanism.

Then, in step S12, the winding core 12 is rotated a predetermined number of times, so that the separator sheets 2 and 3 are wound around the winding core 12 by a predetermined amount. Thereafter, the rotation of the winding core 12 is temporarily stopped.

Next, in step S13, the electrode sheets 4 and 5 are sequentially supplied to the winding core 12 side by the sheet insertion mechanism 71 (see FIG. 7). The supplied electrode sheets 4 and 5 are inserted between the separator sheets 2 and 3. In this embodiment, in order to ensure that the negative electrode sheet 5 covers the positive electrode sheet 4 (particularly the active material coating portion 4a), the tip of the negative electrode sheet 5 is slightly larger than the tip of the positive electrode sheet 4. , 5 in the conveyance direction (front side in the rotational direction of the winding core 12). After the electrode sheets 4 and 5 are supplied, the touch roller 13 moves toward the winding core 12, and the various sheets 2 to 5 are pressed by the touch roller 13.

Next, in step S14, a first detection process is performed. The first detection process is a process for detecting positive electrode position information and negative electrode position information after the electrode sheets 4 and 5 are supplied to the winding core 12 side and before the winding core 12 starts rotating. be. That is, the first detection process is a process for detecting information regarding the position of each tip of the electrode sheets 4 and 5 at the time when the electrode sheets 4 and 5 are supplied to the winding core 12.

In the first detection step, the first positive electrode sensor 14a detects, as positive electrode position information, information regarding whether or not the positive electrode mark 4x is hidden by the positive electrode sheet 4 (see FIG. 8). . In addition, the first negative electrode sensor 15a detects, as negative electrode position information, information regarding whether or not the negative electrode mark 5x is hidden by the negative electrode sheet 5 (see FIG. 9). In addition, in FIG. 8 etc., illustration of the separator sheets 2 and 3 is abbreviate|omitted. Further, in FIG. 8 and the like, the electrode sheets 4 and 5 are shown thicker than they actually are.

In the following step S15, the determination unit 92 performs a quality determination regarding the positions of the tips of each of the electrode sheets 4 and 5 based on the positive electrode position information and the negative electrode position information detected in step S14. Here, if the color of the colored part 4y is not detected by the first positive electrode sensor 14a and the positive electrode mark 4x is covered with the positive electrode sheet 4 (the state shown in FIG. 13), the determination part 92, it is determined that the position of the tip of the positive electrode sheet 4 is "good". Further, when the color of the colored portion 5y is not detected by the first negative electrode sensor 15a and the negative electrode mark 5x is covered with the negative electrode sheet 5 (the state shown in FIG. 13), the determination portion 92 Accordingly, it is determined that the position of the tip of the negative electrode sheet 5 is "good".

On the other hand, when the first positive electrode sensor 14a detects the color of the colored portion 4y and at least a portion of the positive electrode mark 4x is uncovered (the state shown in FIG. 14), the determination section 92 determines that The position of the tip of the positive electrode sheet 4 is determined to be "defective". Further, when at least a part of the negative electrode mark 5x is not covered by the negative electrode sheet 5 (the state shown in FIG. 14), the determination unit 92 determines that the position of the tip of the negative electrode sheet 5 is "defective". It is determined that The determination result is stored in the storage device.

If the positions of the tips of the electrode sheets 4 and 5 are determined to be "good", the process moves to step S16. On the other hand, if the position of at least one of the tip ends of the electrode sheets 4 and 5 is determined to be "defective", the process moves to step S19, which will be described later.

In step S16, the winding of the various sheets 2 to 5 is started by starting the rotation of the winding core 12. After the start of winding, when the winding core 12 rotates about half a revolution, the touch roller 13 separates from the various sheets 2 to 5.

Next, in step S17, a second detection process is performed. The second detection process is a process for detecting positive electrode position information and negative electrode position information after the rotation of the winding core 12 is started until the electrode sheets 4 and 5 are wound up for one revolution. That is, the second detection process is a process for detecting information regarding the position of each tip of the electrode sheets 4 and 5 immediately after the start of winding of the various sheets 2 to 5. In this embodiment, the positive electrode position information and the negative electrode position information are detected when the electrode sheets 4 and 5 are wound up more than half a turn and less than one turn.

In the second detection step, the second positive electrode sensor 14b detects, as positive electrode position information, information regarding whether or not the positive electrode mark 4x is hidden by the positive electrode sheet 4 (see FIG. 10). . In addition, the second negative electrode sensor 15b detects, as negative electrode position information, information regarding whether or not the negative electrode mark 5x is hidden by the negative electrode sheet 5 (see FIG. 11).

Next, in step S18, the determination unit 92 performs a quality determination regarding the position of the tip end of each of the electrode sheets 4 and 5 based on the positive electrode position information and negative electrode position information detected in step S17. This determination method is the same as the determination method in step S15, so a description thereof will be omitted. The determination result is stored in the storage device. Incidentally, based on the determination results stored in the storage device, the administrator (operator, etc.) can grasp the occurrence status of defects.

If the positions of the tips of the electrode sheets 4 and 5 are determined to be "good", the process moves to step S20. On the other hand, if the position of at least one of the tip ends of the electrode sheets 4 and 5 is determined to be "defective", the process moves to step S19.

In step S19, a defective electrode sheet cutting process is performed. That is, if it is determined to be "defective" in step S15, that is, if it is determined to be "defective" before the start of winding of the various sheets 2 to 5, the rotation of the winding core 12 is not started. , the winding core 12 is maintained in a stopped state. On the other hand, if it is determined to be "defective" in step S19, that is, if it is determined to be "defective" after the start of winding of the various sheets 2 to 5, the rotation of the winding core 12 is immediately stopped. In this manner, in this embodiment, if it is determined to be "defective" in step S15 or step S18, the winding of the electrode sheets 4, 5 is stopped before the winding of the electrode sheets 4, 5 is completed. .

Thereafter, in a state where the winding core 12 is stopped, the electrode sheets 4 and 5 are gripped by the gripping parts 71a and 71b, and then the electrode sheets 4 and 5 are cut by the sheet cutting cutter 72 (see FIG. 12). After cutting the electrode sheets 4 and 5, the process moves to step S22. In the defective electrode sheet cutting process, the various sheets 2 to 5 are held down by the touch roller 13, and then the electrode sheets 4 and 5 are cut.

On the other hand, if it is determined to be "good" in step S15 and step S18, it is repeatedly determined in step S20 whether or not the electrode sheets 4 and 5 have been wound for a predetermined length (length for one element). . Then, when the electrode sheets 4 and 5 are wound for a predetermined length (step S20: Yes), a normal electrode sheet cutting process is performed in step S21. That is, after the rotation of the winding core 12 is temporarily stopped, the electrode sheets 4 and 5 are gripped by the gripping parts 71a and 71b. Thereafter, the electrode sheets 4 and 5 are cut by the sheet cutting cutter 72.

In step S22 following step S19 or step S21, the rotation of the winding core 12 is restarted, so that the terminal end portions (unwound portions) of the electrode sheets 4 and 5 are wound up.

Thereafter, in step S23, the end portions of the separator sheets 2 and 3 are rolled up. That is, first, the separator sheets 2 and 3 are cut by the separator cutter while the separator sheets 2 and 3 are held by the separator holding means. Then, by rotating the winding core 12 while pressing the various sheets 2 to 5 with the touch roller 13, the end portions of the separator sheets 2 and 3 are completely wound up without coming apart.

In the following step S24, winding end processing is performed. In the winding end process, the end portions of the separator sheets 2 and 3 are stopped by a holding tape (not shown). As a result, if it is determined to be "good" in step S15 and step S18, the battery element 1 is completed by winding up the various sheets 2 to 5 for one element. On the other hand, if the element is determined to be "defective" in step S15 or step S18, a defective element is obtained. The lengths of the various sheets 2 to 5 constituting the defective element are significantly smaller than the lengths of the various sheets 2 to 5 constituting the normal battery element 1.

Thereafter, in step S25, the battery element 1 or the defective element is removed from the winding core 12 by the removing device. The battery element 1 is sent to a subsequent process. On the other hand, the defective elements are discarded without being sent to a subsequent process.

As described in detail above, according to the present embodiment, the positions of the tips of the electrode sheets 4 and 5 are directly detected using the marks 4x and 5x. can be detected more accurately, and the accuracy of pass/fail determination can be improved.

Furthermore, it is possible to more reliably prevent defective wound elements (the defective elements) in which the tip ends of the electrode sheets 4 and 5 are misaligned from being sent to the subsequent process. Therefore, it is possible to effectively suppress the occurrence of wasteful work in the post-process.

Furthermore, if the position of the tip end of the electrode sheets 4, 5 is determined to be "defective", the winding control device 91 causes the electrode sheets 4, 5 to be winding is stopped. Therefore, waste of materials ( electrode sheets 4, 5, etc.) can be reduced as much as possible, and production costs can be reduced. Furthermore, it is possible to more reliably prevent the various sheets 2 to 5 from continuing to be wound up even though the tips of the electrode sheets 4 and 5 are misaligned, and the next battery element 1 can be quickly manufactured. can move to. Therefore, production efficiency can be improved.

In addition, since separate positive electrode marks 4x and negative electrode marks 5x are used, positive electrode position information and negative electrode position information can be detected with higher accuracy. As a result, the position of the tip end of each electrode sheet 4, 5 can be judged more accurately.

In addition, the positive electrode position information and negative electrode position information are not the distance between the marks 4x, 5x and the tips of the electrode sheets 4, 5, but whether the marks 4x, 5x are hidden by the electrode sheets 4, 5. Information about the information is detected. Therefore, information can be detected more easily, and accuracy regarding quality determination can be further improved.

In particular, in this embodiment, the marks 4x, 5x are hidden by the electrode sheets 4, 5 based on whether the colors of the colored parts 4y, 5y are detected by the sensors 14a, 14b, 15a, 15b consisting of color sensors. Information regarding whether the state is present or not is detected. Therefore, a device (tip position detection means) for detecting the position of the tip of the electrode sheets 4, 5 with respect to the marks 4x, 5x can be realized at a lower cost. As a result, it is possible to reduce costs related to manufacturing, maintenance, etc. of the winding device 10.

Furthermore, before the rotation of the winding core 12 for winding up the various sheets 2 to 5 is started, positive electrode position information and negative electrode position information are detected, and a quality determination is made based on this information. Therefore, it is possible to determine whether the electrode sheets 4, 5 are defective in position at the very early stage of the winding process of the various sheets 2-5. Thereby, waste of materials can be further reduced, and production costs can be further reduced. In addition, in the event that the tip ends of the electrode sheets 4 and 5 are misaligned, the next battery element 1 can be manufactured quickly, and production efficiency can be further improved.

In addition, the positive electrode position information and the negative electrode position information are detected from the start of the rotation of the winding core 12 until the electrode sheets 4 and 5 are wound up for one revolution, and a quality judgment is made based on this information. It will be done. Therefore, not only is the positional deviation caused by the slippage of the electrode sheets 4 and 5 relative to the gripping portions 71a and 71b when the electrode sheets are supplied to the winding core 12, but also the electrodes relative to the separator sheets 2 and 3 when the winding core 12 starts rotating. It is also possible to detect positional deviations caused by slipping of the sheets 4 and 5. Therefore, the accuracy of quality determination regarding positional deviation can be further improved.

Furthermore, in the present embodiment, if it is determined to be "defective" based on the positive electrode position information etc. detected before the rotation of the winding core 12, the cause of the positional shift is determined to be due to a problem with the winding core 12. This can be identified as slippage of the electrode sheets 4, 5 with respect to the gripping parts 71a, 71b when the electrode sheets 4, 5 are being supplied. In addition, while it was determined that the electrode sheets 4 and 5 were "good" based on the positive electrode position information etc. detected before the rotation of the winding core 12 started, the electrode sheets 4 and 5 were If it is determined to be "defective" based on the positive electrode position information etc. detected before the winding is completed, the cause of the positional deviation is the electrode sheet relative to the separator sheets 2 and 3 at the time when the winding core 12 starts rotating. It can be determined that the slip is 4 or 5. By making it easier to identify the cause, it is possible to effectively reduce the effort and time required to respond to the occurrence of a defective product (the defective element) (for example, inspecting the winding device 10, etc.).

In addition, since the colored parts 4y and 5y that constitute the marks 4x and 5x have a different color from each color of the electrode sheets 4 and 5 and the outer peripheral surface of the winding core 12, the positive electrode position information and the negative electrode position information can be detected more accurately. can do. As a result, pass/fail determination can be made more accurately.

Furthermore, since the colored portions 4y, 5y are located on the bottom surfaces of the recesses 124, 125, the separator sheets 2, 3, etc. are less likely to come into contact with the colored portions 4y, 5y. Therefore, it is possible to more reliably prevent the colored parts 4y, 5y from peeling off or chipping due to repeated manufacturing of the battery element 1, and to accurately detect positive electrode position information and negative electrode position information over a long period of time. be able to. Furthermore, since the frequency of maintenance and parts replacement regarding the marks 4x and 5x can be reduced, it is possible to more effectively reduce production costs and improve production efficiency.

In addition, the recesses 124 and 125 are not provided on the surface of the outer peripheral surface of the winding core 12 around which the separator sheets 2 and 3 are wound. Therefore, it is possible to prevent the inner peripheral portion of the battery element 1 from entering the recesses 124 and 125. Thereby, the battery element 1 can be more easily removed from the winding core 12. Further, when removing the battery element 1 from the winding core 12, it is possible to more reliably prevent damage to the battery element 1 caused by the recesses 124 and 125, and to improve the quality of the battery element 1.

Note that the present invention is not limited to the content described in the above embodiment, and may be implemented as follows, for example. Of course, other applications and modifications not exemplified below are also possible.

(a) In the electrode sheet supply mechanisms 31 and 41 in the above embodiments, the tip ends of the electrode sheets 4 and 5 supplied to the winding core 12 are located on the upstream side along the conveying direction of the electrode sheets 4 and 5 (the winding core 12 However, it basically does not occur downstream along the transport direction (front side in the rotational direction). Therefore, in detecting the positive electrode position information and the negative electrode position information, it is sufficient to provide one positive electrode mark 4x and one negative electrode mark 5x.

On the other hand, an electrode sheet supply structure in which the leading ends of the electrode sheets 4 and 5 supplied to the winding core 12 can be shifted not only to the upstream side along the conveyance direction but also to the downstream side along the conveyance direction. When the mechanisms 31 and 41 are provided, two positive electrode marks 4x and two negative electrode marks 5x may be provided. For example, as shown in FIG. 15, a pair of positive electrode marks 4x1, 4x2 and a pair of negative electrode marks 5x1, 5x2 may be provided on the outer peripheral surface of the winding core 12. In this case, if only one of the pair of marks 4x1, 4x2 (5x1, 5x2) is hidden by the electrode sheet 4 (5), the position of the tip of the electrode sheet 4 (5) is "good". ”, and if the pair of marks 4x1, 4x2 (5x1, 5x2) is hidden by the electrode sheet 4 (5) or the pair of marks 4x1, 4x2 (5x1, 5x2) is exposed, then the electrode The configuration may be such that the position of the leading end of the sheet 4 (5) is determined to be "defective". With this configuration, it becomes possible to detect not only the positional deviation of the tip portions of the electrode sheets 4 and 5 toward the upstream side, but also the positional displacement toward the downstream side. In order to further improve the detection accuracy, it is preferable that the colored portions of the positive electrode marks 4x1 and 4x2 have different colors, and the colored portions of the negative electrode marks 5x1 and 5x2 have different colors. .

(b) The mark may be any mark that serves as a reference for detecting information regarding the position of the tip of the electrode sheets 4, 5, and is not limited to those mentioned in the above embodiment.

Therefore, for example, as shown in FIG. 16, a groove 126 extending in the direction of the rotation axis of the winding core 12 is provided on the outer peripheral surface of the winding core 12, and the mark 45x is formed by the edge formed by this groove 126. Good too. Further, the mark may be formed by a slit 123 or a stamp provided on the outer peripheral surface of the winding core 12.

Further, as in the example shown in FIG. 16, only one mark may be provided and the mark may be used in common when detecting positive electrode position information and negative electrode position information.

(c) In the above embodiment, the configuration is such that information regarding whether or not the marks 4x and 5x are hidden by the electrode sheets 4 and 5 is detected as the positive electrode position information and the negative electrode position information. . On the other hand, as positive electrode position information and negative electrode position information, the distance from the mark to the tip of the electrode sheets 4 and 5 and the area of the part of the mark that is not covered with the electrode sheets 4 and 5 are detected. may be configured. In this case, as the tip position detection means, a camera that images the tips of the electrode sheets 4 and 5 and a device that calculates the distance and the area based on the image data obtained by the camera may be provided. .

Furthermore, a notification means may be provided to notify the outside of the apparatus that the apparatus needs to be inspected when the distance or the area exceeds a predetermined threshold.

(d) In the above embodiment, the winding portion 11 includes one winding core 12, but may include a plurality of winding cores.

(e) In the above embodiment, the active material non-coated parts 4b and 5b, which are the parts of the electrode sheets 4 and 5 that protrude from the widthwise edges of the separator sheets 2 and 3, are located along the longitudinal direction of the electrode sheets 4 and 5. It is configured to extend continuously. On the other hand, a configuration may be adopted in which the portions of the electrode sheets 4 and 5 that protrude from the widthwise edges of the separator sheets 2 and 3 are provided at intervals along the longitudinal direction.

For example, as shown in FIGS. 17 and 18, molded tabs 4c and 5c, which are formed by partially cutting off the electrode sheets 4 and 5, are placed on the widthwise edges of the electrode sheets 4 and 5 at intervals along the longitudinal direction. The molded tabs 4c and 5c may protrude from the edges of the separator sheets 2 and 3 in the width direction.

Further, as shown in FIGS. 19 and 20, active material application parts 4a and 5a are provided intermittently, and welding tabs 4d and 5d are fixed between each active material application part 4a and 5a. The electrode sheets 4 and 5 may be configured such that these welding tabs 4d and 5d protrude from the widthwise edges of the separator sheets 2 and 3. A protective tape 7 is attached to the welding locations of the welding tabs 4d and 5d.

As shown in FIGS. 17 to 20, portions of the electrode sheets 4 and 5 that protrude from the widthwise edges of the separator sheets 2 and 3 are provided at intervals along the longitudinal direction of the electrode sheets 4 and 5. In this case, the cutting positions of the electrode sheets 4 and 5 are adjusted so that the position of the tip of the electrode sheets 4 and 5 (the part to be cut) is always constant. Ru. By detecting information regarding the position of the portion relative to the mark, information regarding the position of the tip of the electrode sheets 4 and 5 relative to the mark is detected. For example, by detecting information about whether the marks 4x, 5x are hidden by the molded tabs 4c, 5c, information about the positions of the tips of the electrode sheets 4, 5 with respect to the marks 4x, 5x can be obtained. Detected.

Note that the electrode sheets 4 and 5 may be provided with tabs other than the above-mentioned molded tabs and welded tabs (for example, crimped tabs, etc.).

(f) In the above embodiment, the sensors 14a, 14b, 15a, 15b are activated during the period after the electrode sheets 4, 5 are supplied to the winding core 12 side and until the winding core 12 starts rotating. It is configured to detect positive electrode position information and the like during the period from the start of rotation of the core 12 until the electrode sheets 4 and 5 are wound up one turn. On the other hand, the configuration may be such that the positive electrode position information and the like are detected only from the time when the electrode sheets 4 and 5 are supplied to the core 12 until the core 12 starts rotating. Alternatively, the positive electrode position information or the like may be configured to be detected only from the time when the core 12 starts rotating until the electrode sheets 4 and 5 are wound up one turn. In addition, considering that the tip ends of the electrode sheets 4 and 5 may be misaligned after the winding of the electrode sheets 4 and 5 is started, the electrode sheets 4 and 5 are wound one round after the rotation of the winding core 12 is started. It is preferable to configure the configuration so that positive electrode position information and the like are detected until the positive electrode position information is taken.

Further, in the embodiment described above, the determining unit 92 is configured to perform quality determination before and during winding of the electrode sheets 4 and 5. The step 5 may be performed before or during winding.

(g) In the above embodiment, the battery element 1 of the lithium ion battery is manufactured by the winding device 10, but the winding device manufactured by the winding device 10 is not limited to this, and for example, , it is also possible to manufacture wound elements of electrolytic capacitors, etc.

(h) The materials of the separator sheets 2, 3 and the electrode sheets 4, 5 are not limited to those in the above embodiments, and may be changed as appropriate. Of course, the active material applied to the electrode sheets 4 and 5 may be changed.

1... Lithium ion battery element (wound element), 2, 3... Separator sheet, 4... Positive electrode sheet, 4x... Positive electrode mark (mark), 4y, 5y... Colored part, 5... Negative electrode sheet, 5x... Negative electrode mark, 10... winding device, 12... winding core, 14a... first positive electrode sensor (tip position detection means), 14b... second positive electrode sensor (tip position detection means), 15a... th One negative electrode sensor (tip position detection means), 15b... Second negative electrode sensor (tip position detection means), 31... Positive electrode sheet supply mechanism (electrode sheet supply means), 41... Negative electrode sheet supply mechanism (electrode 91... Winding control device (winding control means), 92... Judgment section (judgment means), 124, 125... Recessed portion.

Claims (8)

1. A belt-shaped electrode sheet having an active material on the surface and a belt-shaped separator sheet made of an insulating material are supplied to a rotatable winding core, and the rotation of the winding core causes the electrode sheet and the separator sheet to separate. A winding device that winds while overlapping,
   Winding control means for controlling rotation of the winding core;
   an electrode sheet supply means for supplying the electrode sheet to the winding core side with the tip end of the electrode sheet as the leading edge;
   a mark provided on the outer peripheral surface of the winding core;
   Tip position detection means for detecting information regarding the position of the tip with respect to the mark along the circumferential direction of the winding core;
   Based on the information detected by the tip position detection means, the quality of the position of the tip of the electrode sheet along the circumferential direction of the winding core is determined before and/or during winding of the electrode sheet. and a determination means for determining,
   The tip position detection means detects the information during a period from when the electrode sheet is supplied to the winding core side by the electrode sheet supply means until the electrode sheet is wound for one round. It is composed of
   The winding control means is configured to be able to control the winding core so that winding of the electrode sheet is stopped before winding of the electrode sheet is completed when the determination means determines that the winding core is defective. A winding device characterized by:
2. The mark is characterized in that a colored portion of a color different from each color of the electrode sheet and the outer peripheral surface of the core is provided on at least the bottom surface of a recess provided on the outer peripheral surface of the core. The winding device according to item 1.
3. The winding device according to claim 2, wherein the recess is provided at a position of the outer circumferential surface of the winding core that is away from a surface on which the separator sheet is wound.
4. 3. The tip position detection means is configured to detect, as the information, information regarding whether or not the mark is hidden by the electrode sheet. The winding device described in .
5. The tip position detection means includes a color sensor capable of detecting the color of the colored portion, and depending on whether or not the color of the colored portion is detected by the color sensor, the position of the mark is determined by the electrode sheet. The winding device according to claim 4, wherein the winding device is configured to detect information regarding whether or not the winding device is in a hidden state.
6. The tip position detection means is configured to detect the information between when the electrode sheet is supplied to the winding core side by the electrode sheet supplying means and until rotation of the winding core is started. The winding device according to claim 1, characterized in that:
7. The tip position detection means is characterized in that it is configured to detect the information between the time when the core starts rotating and the time when the electrode sheet is wound for one revolution. The winding device according to claim 1.
8. As the electrode sheets, a band-shaped positive electrode sheet having a positive electrode active material on its surface and a band-shaped negative electrode sheet having a negative electrode active material on its surface are supplied to the winding core, and as the winding core rotates, the positive electrode sheet The electrode sheet and the negative electrode sheet are configured to be rolled while being overlapped,
   As the mark, a predetermined positive electrode mark and a predetermined negative electrode mark are provided separately,
   The tip position detection means includes information regarding the position of the tip of the positive electrode sheet with respect to the positive electrode mark along the circumferential direction of the winding core, and information regarding the position of the tip of the positive electrode sheet with respect to the negative electrode mark along the circumferential direction of the winding core. Detecting information regarding the position of the tip of the negative electrode sheet,
   The determining means determines the quality of the positions of the respective leading ends of the positive electrode sheet and the negative electrode sheet along the circumferential direction of the winding core, based on the information detected by the leading end position detecting means. The winding device according to claim 1, characterized in that it is configured as follows.

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