Manufacturing apparatus of power storage device

Abstract

To reduce damage to tabs.SOLUTION: A manufacturing apparatus 100 of a power storage device comprises a winding shaft 110, a first carrier 120, a second carrier 130, a first laser tab cut processor 150, a second laser tab cut processor 160, a winder 170, and a controller 180. The controller 180 is configured so as to perform: a first process S11 for obtaining a tab pitch on a positive electrode sheet 21 to be wound up by the winding shaft 110; a second process S12 for obtaining a tab pitch on a negative electrode sheet 22 to be wound up by the winding shaft 110; a third process S13 for adjusting a distance between tabs 21d based on the tab pitch on the positive electrode sheet 21 obtained by the first process S11; and a fourth process S14 for adjusting a distance between tabs 22d based on the tab pitch on the negative electrode sheet 22 obtained by the second process S12.SELECTED DRAWING: Figure 3

Description

[Technical field]

[0001] The present invention relates to an apparatus for manufacturing an electricity storage device. [Background technology]

[0002] Japanese Patent No. 5572676 discloses a winding device that winds a strip-shaped sheet on which a plurality of laminated portions are intermittently formed along the sheet longitudinal direction. The winding device includes a winding core, a first pressing means, a detection means, a position adjustment means, and a second pressing means. The winding core is rotatably provided. The first pressing means is provided to be rotatable integrally with the winding core while pressing the sheet wound around the winding core. The detection means detects the position of the end of the laminated portion on the sheet in the longitudinal direction of the sheet wound around the winding core. The position adjustment means is configured to be movable at least along the sheet winding direction while gripping the sheet wound around the winding core. The position adjustment means aligns the end position of the laminated portion on the sheet in the longitudinal direction of the sheet to a preset reference position based on the detection result of the detection means. The second pressing means presses the sheet in the aligned state. It is said that such a winding device can precisely align the positions of the plurality of laminated portions. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Patent No. 5572676 Summary of the Invention [Problem to be solved by the invention]

[0004] The present inventors wish to improve the positional accuracy of electrode tabs in electricity storage devices. [Means for solving the problem]

[0005] The manufacturing apparatus for the electric storage device disclosed herein includes a winding shaft, a first conveying device, a first laser tab cut processing device, a second conveying device, a second laser tab cut processing device, a winding device, and a control device. The first conveying device conveys a strip-shaped positive electrode sheet toward the winding shaft. The first laser tab cut processing device forms tabs at predetermined intervals on the positive electrode sheet conveyed by the first conveying device. The second conveying device conveys a strip-shaped negative electrode sheet toward the winding shaft. The second laser tab cut processing device forms tabs at predetermined intervals on the negative electrode sheet conveyed by the second conveying device. The winding device rotates the winding shaft and winds up the positive electrode sheet on which the tabs are formed by the first laser tab cut processing device and the negative electrode sheet on which the tabs are formed by the second laser tab cut processing device. The positive electrode sheet has a strip-shaped positive electrode current collector foil and a positive electrode active material layer formed in an area of ​​the strip-shaped positive electrode current collector foil except for an unformed area set at a first edge in the width direction. The negative electrode sheet has a strip-shaped negative electrode current collector foil and a negative electrode active material layer formed in an area of ​​the strip-shaped negative electrode current collector foil except for an unformed area set at a first edge in the width direction. The control device is configured to execute a first process of acquiring a tab pitch of the positive electrode sheet to be wound around the winding shaft for a rotation angle of the winding shaft, a second process of acquiring a tab pitch of the negative electrode sheet to be wound around the winding shaft for a rotation angle of the winding shaft, a third process of adjusting the spacing of the tabs formed on the positive electrode sheet by the first laser tab cut processing device based on the tab pitch of the positive electrode sheet to be wound around the winding shaft for a rotation angle of the winding shaft acquired in the first process, and a fourth process of adjusting the spacing of the tabs formed on the negative electrode sheet by the second laser tab cut processing device based on the tab pitch of the negative electrode sheet to be wound around the winding shaft for a rotation angle of the winding shaft acquired in the second process. In this manufacturing apparatus for an electric storage device, damage to the tabs is reduced. [Brief description of the drawings]

[0006] [Figure 1] FIG. 1 is a cross-sectional view of an electricity storage device 1. As shown in FIG. [Diagram 2] FIG. 2 is a schematic diagram of the wound electrode body 20. As shown in FIG. [Diagram 3]FIG. 3 is a schematic diagram showing an apparatus 100 for manufacturing an electricity storage device. [Figure 4] FIG. 4 is a schematic diagram of the winding shaft 110. [Diagram 5] FIG. 5 is a schematic diagram of the positive electrode sheet 21 on which the tabs 21d are formed. [Figure 6] FIG. 6 is a block diagram showing the processing executed by the control device 180. As shown in FIG. [Figure 7] FIG. 7 is a schematic diagram showing the first tab detection device 201. As shown in FIG. [Figure 8] FIG. 8 is a block diagram illustrating the processing performed by a controller 180 according to another embodiment. [Figure 9] FIG. 9 is a schematic diagram showing the image inspection devices 204 and 205. [Figure 10] FIG. 10 is a schematic diagram showing the image inspection device 206. [Figure 11] FIG. 11 is a schematic diagram showing the wound body 20a after the preliminary pressing. [Figure 12] FIG. 12 is a block diagram illustrating the processing performed by a controller 180 according to another embodiment. [Figure 13] FIG. 13 is a schematic diagram showing the thickness inspection device 207. [Figure 14] FIG. 14 is a block diagram illustrating the processing performed by a controller 180 according to another embodiment. [Figure 15] FIG. 15 is a block diagram illustrating the processing performed by a controller 180 according to another embodiment. [Figure 16] FIG. 16 is a block diagram illustrating the processing performed by a controller 180 according to another embodiment. [Figure 17] FIG. 17 is a block diagram illustrating the processing performed by a controller 180 according to another embodiment. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0007] Hereinafter, an embodiment of the technology disclosed herein will be described with reference to the drawings. The embodiment described herein is, of course, not intended to limit the present invention in particular. Each drawing is drawn typically and does not necessarily reflect the actual product. Furthermore, the same reference numerals are appropriately used for members and parts that perform the same function, and duplicated descriptions are appropriately omitted.

[0008] Fig. 1 is a cross-sectional view of an electricity storage device 1. In Fig. 1, the electricity storage device 1 is illustrated diagrammatically with the wide surface on the front side of a case 10 virtually removed so that the inside of the case 10 can be seen. The electricity storage device 1 is one form of an electricity storage device manufactured by the electricity storage device manufacturing apparatus 100 disclosed herein, and a wound electrode body 20 is housed inside the case 10. The electricity storage device manufactured by the electricity storage device manufacturing apparatus disclosed herein is not limited to the form shown in Fig. 1.

[0009] "Electricity storage device 1" The electricity storage device 1 is a horizontally elongated rectangular electricity storage device. As shown in Fig. 1, the electricity storage device 1 has a case 10, a wound electrode body 20, a positive electrode terminal 50, and a negative electrode terminal 60. The case 10 has a case body 11 and a lid 12.

[0010] <Case body 11> The case body 11 is a bottomed rectangular case having a horizontally long rectangular storage space. The case body 11 mainly stores the wound electrode body 20. The case body 11 has a substantially rectangular bottom surface, a pair of opposing wide surfaces along the long sides of the bottom surface, and a pair of opposing narrow surfaces along the short sides of the bottom surface. An opening 11f for storing the wound electrode body 20 is formed on the surface opposite the bottom surface. A lid 12 is attached to the opening 11f.

[0011] <Lid 12> The lid 12 is attached to the opening 11f of the case 10. The lid 12 is made of a substantially rectangular plate material that can be attached to the opening 11f of the case body 11. The lid 12 is a substantially rectangular plate material, and has an attachment hole 12a for attaching the positive electrode terminal 50 formed on one side in the longitudinal direction, and an attachment hole 12b for attaching the negative electrode terminal 60 formed on the opposite side.

[0012] The lid 12 is provided with a liquid injection hole 12c and a gas exhaust valve 12d. The liquid injection hole 12c is a through hole provided for injecting a non-aqueous electrolyte into the case 10 after sealing. The liquid injection hole 12c is sealed by attaching a sealing member 12e after the non-aqueous electrolyte is injected. The gas exhaust valve 12d is a thin-walled portion designed to break (open) when a large amount of gas is generated inside the case 10 and to exhaust the gas.

[0013] The non-aqueous electrolyte may be any electrolyte used in a conventionally known electricity storage device without any particular limitation. For example, the non-aqueous electrolyte may be prepared by dissolving a supporting salt in a non-aqueous solvent.

[0014] <Positive terminal 50, negative terminal 60> The positive electrode terminal 50 and the negative electrode terminal 60 are attached to the lid 12. The wound electrode body 20 is housed in the case body 11 in a state where it is attached to the positive electrode terminal 50 and the negative electrode terminal 60. The positive electrode terminal 50 includes an external connection portion 51 and an axis portion 52. The negative electrode terminal 60 includes an external connection portion 61 and an axis portion 62. The positive electrode terminal 50 and the negative electrode terminal 60 are each connected via an insulator 70. The positive electrode terminal 50 and the negative electrode terminal 60 are each connected to internal terminals 53, 63 provided in the case 10.

[0015] The external connection parts 51, 61 are disposed on the outside of the lid 12 with an insulator 70 interposed therebetween. The internal terminals 53, 63 are attached to the inside of the lid 12 with a gasket 80 interposed therebetween. The insulator 70 and the gasket 80 are made of insulating material. The insulator 70 and the gasket 80 are made of resin having a required rigidity. The internal terminals 53, 63 have mounting holes and are connected to the shaft parts 52, 62 of the positive terminal 50 and the negative terminal 60, respectively. The lower ends of the shaft parts 52, 62 are crimped around the mounting holes of the internal terminals 53, 63.

[0016] The positive electrode terminal 50 and the negative electrode terminal 60 are attached to the lid 12 in a state in which they are electrically insulated via an insulator 70 and a gasket 80 and in a state in which airtightness is ensured. The positive electrode terminal 50 and the negative electrode terminal 60 are connected to the wound electrode body 20 via internal terminals 53, 63. The wound electrode body 20 is housed in the case body 11 in a state in which it is attached to the lid 12 in this manner. A plurality of wound electrode bodies 20 may be attached to one lid 12, and a plurality of wound electrode bodies 20 may be housed in one case 10.

[0017] <Wound electrode body 20> FIG. 2 is a schematic diagram of the wound electrode body 20. In FIG. 2, the wound electrode body 20 is illustrated in a state where one end is unfolded. As shown in FIG. 2, the wound electrode body 20 is, for example, a long strip-shaped positive electrode sheet 21, a first separator 31, a negative electrode sheet 22, and a second separator 32, which are stacked in order with their longitudinal directions aligned and wound around a winding axis WL set in the width direction. The positive electrode sheet 21 and the negative electrode sheet 22 are also referred to as a positive electrode plate and a negative electrode plate, respectively.

[0018] The positive electrode sheet 21 includes a strip-shaped positive electrode current collector foil 21a, a positive electrode active material layer 21b, and a tab 21d. The positive electrode current collector foil 21a is a base material of the positive electrode sheet 21. The positive electrode current collector foil 21a is formed of a predetermined metal foil (for example, aluminum foil). In the strip-shaped positive electrode current collector foil 21a, a first edge portion 21a1 is set at one end in the width direction (left side in FIG. 2), and a second edge portion 21a2 is set at the other end (right side in FIG. 2). An unformed region 21a3 is set at the first edge portion 21a1 in the width direction of the strip-shaped positive electrode current collector foil 21a. The positive electrode active material layer 21b is formed in a region other than the unformed region 21a3. The positive electrode active material layer 21b is formed on the positive electrode current collector foil 21a with a constant width from one end of the width direction. A protective layer 21c containing insulating ceramic particles may be formed on the positive current collector foil 21a except for the portion on which the positive active material layer 21b is formed. Furthermore, a tab 21d protruding in the width direction is formed on the positive current collector foil 21a on the side on which the protective layer 21c is formed. The tab 21d is a portion that partially protrudes by a predetermined width on the side on which the protective layer 21c is formed. The positive current collector foil 21a is exposed at the tab 21d. Note that the protective layer 21c is not an essential component of the positive electrode sheet.

[0019] The positive electrode active material layer 21b is a layer containing a positive electrode active material. In a lithium ion secondary battery, the positive electrode active material is, for example, a material that can release lithium ions during charging and absorb lithium ions during discharging, such as a lithium transition metal composite material. In general, various positive electrode active materials have been proposed other than the lithium transition metal composite material, and are not particularly limited.

[0020] The negative electrode sheet 22 includes a strip-shaped negative electrode current collector foil 22a, a negative electrode active material layer 22b, and a tab 22d. The negative electrode current collector foil 22a is a base material of the negative electrode sheet 22. The negative electrode current collector foil 22a is formed of a predetermined metal foil (for example, copper foil). In the strip-shaped negative electrode current collector foil 22a, a first edge portion 22a1 is set at one end in the width direction (left side in FIG. 2), and a second edge portion 22a2 is set at the other end (right side in FIG. 2). An unformed region 22a3 is set at the first edge portion 22a1 in the width direction of the strip-shaped negative electrode current collector foil 22a. The negative electrode active material layer 22b is formed in a region other than the unformed region 22a3. The negative electrode active material layer 22b is formed on the negative electrode current collector foil 22a with a constant width from one end portion in the width direction. The negative electrode current collector foil 22a has a tab 22d formed thereon, which protrudes from one side in the width direction. The tab 22d is a portion that protrudes partially by a predetermined width toward the outside on the side where the unformed region 22a3 is provided. The negative electrode current collector foil 22a is exposed at the tab 22d.

[0021] In this embodiment, the positive electrode sheet 21 and the negative electrode sheet 22 have the unformed regions 21a3 and 22a3 set at the first edges 21a1 and 22a1 on the same side, but are not limited to such a form. The unformed regions 21a3 and 22a3 may be set at the second edges 21a2 and 22a2 of the positive electrode sheet 21 and the negative electrode sheet 22. One of the unformed regions 21a3 and 22a3 may be set at the first edges 21a1 and 22a1, and the other may be set at the second edges 21a2 and 22a2. In this case, the tabs 21d and 22d may protrude in different directions (for example, opposite directions) from the positive electrode sheet 21 and the negative electrode sheet 22, respectively.

[0022] The negative electrode active material layer 22b is a layer containing a negative electrode active material. The negative electrode active material is not particularly limited as long as it can reversibly absorb and release charge carriers in relation to the above-mentioned positive electrode active material. Examples of such negative electrode active materials include carbon materials and silicon-based materials.

[0023] As shown in FIG. 2, the negative electrode active material layer 22b of the negative electrode sheet 22 may cover the positive electrode active material layer 21b of the positive electrode sheet 21 with the separators 31 and 32 interposed therebetween. The separators 31 and 32 may further cover the positive electrode active material layer 21b of the positive electrode sheet 21 and the negative electrode active material layer 22b of the negative electrode sheet 22. Although not shown in the drawings, the lengths of the positive electrode sheet 21, the negative electrode sheet 22, and the separators 31 and 32 may be such that the separators 31 and 32>the negative electrode sheet 22>the positive electrode sheet 21. The width La of the positive electrode active material layer 21b, the width Ln of the negative electrode active material layer 22b, and the width Ls of the separators 31 and 32 are such that Ls>Ln>La. The area where the positive electrode sheet 21 and the negative electrode sheet 22 overlap, where the positive electrode active material layer 21b is formed, is covered with the negative electrode active material layer 22b. Moreover, the area where the negative electrode active material layer 22b overlaps with the positive electrode sheet 21, where the positive electrode active material layer 21b does not face, is covered with a protective layer 21c.

[0024] As shown in FIG. 2, the tab 21d of the positive electrode sheet 21 protrudes from one side of the separators 31, 32 in the width direction. The positive electrode sheet 21 is provided with a plurality of tabs 21d at a predetermined pitch in the longitudinal direction. The tab 22d of the negative electrode sheet 22 protrudes from the separators 31, 32 on the same side as the side from which the tab 21d of the positive electrode sheet 21 protrudes. The negative electrode sheet 22 is provided with a plurality of tabs 22d at a predetermined pitch in the longitudinal direction. The plurality of tabs 21d of the positive electrode sheet 21 and the plurality of tabs 22d of the negative electrode sheet 22 are provided at a predetermined pitch so that they are in approximately the same position after being wound around the wound electrode body 20.

[0025] As shown in Figs. 1 and 2, the wound electrode body 20 is housed in the case body 11 through the opening 11f to which the lid 12 is attached. For this reason, the wound electrode body 20 has a flat shape to match the shape of the opening 11f. When the wound electrode body 20 is produced, it may be wound around a flat shaft. When the wound electrode body 20 is produced, it may be pressed flat after being wound around a cylindrical shaft. The wound electrode body 20 and the case body 11 are electrically insulated by a resin insulating sheet (not shown) arranged between the wound electrode body 20 and the case body 11.

[0026] Incidentally, as a method for manufacturing a wound electrode body used in an electric storage device, a method of preparing a positive electrode sheet and a negative electrode sheet on which a tab has been formed in advance and winding them is considered. For example, when preparing a positive electrode sheet and a negative electrode sheet, tabs are formed on the positive electrode sheet and the negative electrode sheet according to preset processing conditions. After preparing a positive electrode sheet and a negative electrode sheet on which a tab has been formed, the positive electrode sheet and the negative electrode sheet are wound on a winding shaft via a separator. In contrast, the present inventor has considered cutting the positive electrode sheet and the negative electrode sheet with a laser and winding them while forming the tab. In addition, according to the knowledge of the present inventor, when the positive electrode sheet and the negative electrode sheet are wound, the tabs are not necessarily stacked at a fixed position, and the position of the tab may be shifted within a predetermined allowable range. In cases such as when there is a large variation in thickness within the plane of the positive electrode sheet and the negative electrode sheet, the tab may be shifted beyond a predetermined allowable range. In addition, the tab may be shifted due to processing (pressing, etc.) of the wound body after winding. In particular, when the wound electrode body becomes large and the number of windings increases, the tab is likely to be shifted significantly.

[0027] "Electricity storage device manufacturing apparatus 100" The manufacturing apparatus 100 for an electricity storage device is an apparatus for manufacturing an electricity storage device 1. FIG. 3 is a schematic diagram showing the manufacturing apparatus 100 for an electricity storage device. FIG. 4 is a schematic diagram of a winding shaft 110. As shown in FIG. 3, the manufacturing apparatus 100 for an electricity storage device includes the winding shaft 110, a first conveying device 120, a second conveying device 130, third conveying devices 140 and 141, a first laser tab cut processing device 150, a second laser tab cut processing device 160, a winding device 170, and a control device 180. The manufacturing apparatus 100 for an electricity storage device may include a pressing device 200.

[0028] In the manufacturing apparatus 100 for the electric storage device, the positive electrode sheet 21, the negative electrode sheet 22, and the separators 31, 32 are respectively conveyed by the first conveying device 120, the second conveying device 130, and the third conveying devices 140, 141. During conveyance, the positive electrode sheet 21 and the negative electrode sheet 22 are respectively formed with tabs 21d, 22d by the first laser tab cutting device 150 and the second laser tab cutting device 160. The positive electrode sheet 21 and the negative electrode sheet 22 on which the tabs 21d, 22d are formed are wound around the reel 110 by the winding device 170, and the wound body 20a is produced. In this way, in the manufacturing apparatus 100 for the electric storage device, the positive electrode sheet 21 and the negative electrode sheet 22 are wound while the tabs 21d, 22d are formed on them. Each device will be described below.

[0029] <Reel 110> 4, the winding shaft 110 is a shaft member that winds up the positive electrode sheet 21, the negative electrode sheet 22, and the separators 31 and 32. The positive electrode sheet 21 and the negative electrode sheet 22 are wound up so that the separators 31 and 32 are interposed between them.

[0030] In this embodiment, the winding shaft 110 is a member having a substantially cylindrical shaft shape. The shape of the winding shaft 110 is not particularly limited, and the cross section may be a perfect circle or a flat shape. In this embodiment, a slit 111 is formed in the winding shaft 110. The slit 111 is formed so as to pass through the central axis (winding axis) of the winding shaft 110. The winding shaft 110 has a shape divided in the radial direction by the slit 111. Note that the winding shaft 110 does not necessarily have to have a slit formed therein.

[0031] The winding shaft 110 may be provided with various additional configurations. For example, the winding shaft 110 may be provided with a configuration for sucking in the sheets (in this embodiment, the positive electrode sheet 21, the negative electrode sheet 22, and the separators 31 and 32) wound around the winding shaft 110. A space may be formed inside the winding shaft 110 that creates a negative pressure relative to the outside. The winding shaft 110 may be formed with a hole that penetrates from the space toward the surface of the winding shaft 110. The hole can act as a suction hole that sucks in the sheet wound around the winding shaft 110. This makes it difficult for the position of the sheet to shift when the sheet is wound. In addition, the winding shaft 110 may be provided with a groove that serves as a receiving portion when the sheet wound around the winding shaft 110 is cut. For example, when the sheet is cut after being wound around the winding shaft 110, a cutter blade may be lowered into the groove. This makes it difficult for the winding shaft 110 and the cutter blade to be damaged when the sheet is cut.

[0032] The positive electrode sheet 21, the negative electrode sheet 22, and the separators 31 and 32 are attached to the winding shaft 110. The separators 31 and 32 are attached to the winding shaft 110 so that the positive electrode sheet 21 and the negative electrode sheet 22 do not come into contact with each other. The positive electrode sheet 21, the negative electrode sheet 22, and the separators 31 and 32 may be fixed to the winding shaft 110 by having their respective leading ends sandwiched in slits 111. The winding shaft 110 is driven to rotate in the circumferential direction by a winding device 170 (see FIG. 3).

[0033] <Take-up device 170> The winding device 170 is a device that rotates the winding shaft 110. The winding device 170 rotates the winding shaft 110, thereby winding the positive electrode sheet 21 and the negative electrode sheet 22 onto the winding shaft 110. The winding device 170 is not particularly limited as long as it can rotate the winding shaft 110. As the winding device 170, for example, a motor can be used.

[0034] The positive electrode sheet 21 and the negative electrode sheet 22 are wound around the winding shaft 110 so that the tabs 21d and 22d are arranged at predetermined positions with respect to the rotation angle of the winding shaft 110. The positive electrode sheet 21 and the negative electrode sheet 22 are wound around the winding shaft 110 so that the tabs 21d of the positive electrode sheet 21 and the tabs 22d of the negative electrode sheet 22 overlap in the radial direction. In this embodiment, the positions of the tabs 21d and 22d are set so that the tabs 21d and 22d of the positive electrode sheet 21 and the tabs 22d of the negative electrode sheet 22 overlap at different positions in the circumferential direction. In this embodiment, the positive electrode sheet 21 and the negative electrode sheet 22 are wound around the winding shaft 110 so that the tabs 21d and 22d overlap at a predetermined angle with respect to the reference line of the winding shaft 110. The reference line of the winding shaft 110 can be any line along the radial direction of the winding shaft 110. In this embodiment, the positive electrode tab 21d and the negative electrode sheet 22 are overlapped at positions symmetrical with respect to the slit 111. The overlapped positive electrode tab 21d and negative electrode sheet 22 are each disposed at two positions in the circumferential direction.

[0035] As shown in FIG. 3, the positive electrode sheet 21, the negative electrode sheet 22, and the separators 31, 32 are transported to the winding shaft 110 by a first transport device 120, a second transport device 130, and a third transport device 140, 141, respectively.

[0036] <First conveying device 120, second conveying device 130, third conveying device 140, 141> The first conveying device 120 is a device that conveys the strip-shaped positive electrode sheet 21 toward the winding shaft 110. The second conveying device 130 is a device that conveys the strip-shaped negative electrode sheet 22 toward the winding shaft 110. The third conveying devices 140 and 141 are devices that convey the strip-shaped separators 31 and 32 toward the winding shaft 110.

[0037] The positive electrode sheet 21, the negative electrode sheet 22, and the separators 31 and 32 are wound around the unwinding shafts 122, 132, 142, and 143, respectively. The first conveying device 120, the second conveying device 130, and the third conveying devices 140 and 141 are connected to the unwinding shafts 122, 132, 142, and 143, respectively. The positive electrode roll 124, the negative electrode roll 134, and the separator rolls 144 and 145 are wound around the unwinding shafts 122, 132, 142, and 143, respectively. The positive electrode roll 124 is a roll around which the strip-shaped positive electrode sheet 21 is wound before the tab 21d is formed. The negative electrode roll 134 is a roll around which the strip-shaped negative electrode sheet 22 is wound before the tab 22d is formed. The separator rolls 144 and 145 are rolls around which the strip-shaped separators 31 and 32 are wound, respectively.

[0038] The first conveying device 120, the second conveying device 130, and the third conveying devices 140 and 141 rotate and drive the unwinding shafts 122, 132, 142, and 143, respectively. As a result, the positive electrode roll 124, the negative electrode roll 134, and the separator rolls 144 and 145 are unwound from the unwinding shafts 122, 132, 142, and 143, respectively. The first conveying device 120, the second conveying device 130, and the third conveying devices 140 and 141 are not particularly limited as long as they can rotate the unwinding shafts 122, 132, 142, and 143. For example, a motor or the like can be used as the first conveying device 120, the second conveying device 130, and the third conveying device 140 and 141.

[0039] The conveying speed can be controlled according to conveying conditions set in the control device 180. The positive electrode sheet 21, the negative electrode sheet 22, and the separators 31 and 32 can be conveyed to the winding shaft 110 at a substantially constant speed by the first conveying device 120, the second conveying device 130, and the third conveying device 140 and 141, respectively. The positive electrode sheet 21, the negative electrode sheet 22, and the separators 31 and 32 can be conveyed along a conveying path set in advance. The conveying path may be set by, for example, a nip roller, an accumulator, a tension roller, a guide roller, or the like. The conveying path of the positive electrode sheet 21 is provided with a first laser tab cut processing device 150. The conveying path of the negative electrode sheet 22 is provided with a second laser tab cut processing device 160. In this embodiment, when the wound body 20a with a predetermined number of turns is produced, the conveying of the sheet is stopped. When a new sheet is attached to the reel 110, transportation of the sheet is started by the first transport device 120, the second transport device 130, and the third transport devices 140 and 141. Tab processing is started on the positive electrode sheet 21 and the negative electrode sheet 22 being transported.

[0040] First laser tab cut processing device 150, second laser tab cut processing device 160 The first laser tab cut processing device 150 is a device that forms tabs 21d at a predetermined interval on the positive electrode sheet 21. The first laser tab cut processing device 150 forms tabs 21d in the unformed area 21a3 of the positive electrode sheet 21 transported by the first transport device 120. The second laser tab cut processing device 160 is a device that forms tabs 22d at a predetermined interval on the negative electrode sheet 22. The second laser tab cut processing device 160 forms tabs 22d in the unformed area 22a3 of the negative electrode sheet 22 transported by the second transport device 130. In this embodiment, the positive electrode sheet 21 and the negative electrode sheet 22 are formed at the same first edge portions 21a1, 22a1 in the width direction. However, the present invention is not limited to such a form, and one of the positive electrode sheet 21 and the negative electrode sheet 22 may have a tab formed at the first edge portion, and the other may have a tab formed at the second edge portion.

[0041] Hereinafter, the formation of the tab will be described using as an example the first laser tab cut processing device 150 that forms the tab 21d on the positive electrode sheet 21. The second laser tab cut processing device 160 can be similar to the first laser tab cut processing device 150, and therefore a detailed description thereof will be omitted.

[0042] The first laser tab cut processing device 150 may include, for example, a chamber, a laser oscillator, and a scanner. The chamber encloses a space in which the tab 21d is formed on the positive electrode sheet 21. The positive electrode sheet 21 may be irradiated with a laser while being transported inside the chamber, and the tab 21d may be formed. The laser oscillator is a device that irradiates a laser. The wavelength, frequency, output, etc. of the laser are appropriately set. The laser oscillator may be attached to a scanner that controls the irradiation angle, position, etc. of the laser. The scanner controls the irradiation of the laser, and thus the trajectory of the laser irradiated on the positive electrode sheet 21 may be determined.

[0043] FIG. 5 is a schematic diagram of the positive electrode sheet 21 on which the tab 21d is formed. In FIG. 5, the trajectory L of the laser irradiated to the positive electrode sheet 21 is indicated by a broken line. As shown in FIG. 5, the positive electrode sheet 21 conveyed has an unformed region 21a3 formed at a first edge 21a1 in the width direction. The second edge 21a2 in the width direction does not have an unformed region 21a3 formed therein and is covered with the positive electrode active material layer 21b. The laser is irradiated to the first edge 21a1 side on which the unformed region 21a3 is formed. According to the trajectory L of the laser, the end of the positive electrode sheet 21 on the first edge 21a1 side is cut.

[0044] In the region where the tabs 21d are formed, the locus L is set so as to follow the shape and dimensions of the tabs 21d. Between the regions where the tabs 21d are formed, the locus L is set so as to extend along the length direction of the positive electrode sheet 21 toward the upstream side of the positive electrode sheet 21 by a length (the interval G between adjacent tabs 21d) corresponding to the pitch of the tabs 21d. As a result, the tabs 21d of a predetermined shape are formed at a predetermined pitch on the positive electrode sheet 21.

[0045] In this embodiment, between the regions where the tabs 21d are formed, the locus L is set to pass through the positive electrode active material layer 21b along the length direction. As a result, the tabs 21d covered with the positive electrode active material layer 21b up to a part of the base end are formed in the positive electrode sheet 21. In order to reduce waste of the positive electrode active material, the locus L may be set in the vicinity of the unformed region 21a3. Without being limited to such a form, the locus L may be set to pass only through the unformed region 21a3. As a result, waste of the positive electrode active material can be reduced. The pieces cut from the positive electrode sheet 21 by the laser can be collected by a waste material separation device (not shown).

[0046] The pitch, dimensions, etc. of the tabs 21d are appropriately set according to the desired configuration of the wound electrode body 20 (see FIG. 2). The pitch of the formed tabs 21d and the interval G between the tabs 21d are not constant, and the pitch of the tabs 21d is set so that the tabs 21d of the wound positive electrode sheet 21 overlap in the radial direction when the wound body 20a (see FIG. 4) is produced.

[0047] As shown in FIG. 3, the positive electrode sheet 21 on which the tab 21d is formed by the first laser tab cut processing device 150 and the positive electrode sheet 21 on which the tab 22d is formed by the second laser tab cut processing device 160 are wound around the winding shaft 110 by the winding device 170. When the positive electrode sheet 21, the negative electrode sheet 22, and the separators 31 and 32 are wound around the winding shaft 110 a predetermined number of times, the winding device 170 is stopped. The positive electrode sheet 21, the negative electrode sheet 22, and the separators 31 and 32 wound around the winding shaft 110 are cut by a cutter or the like (not shown), and the separators 31 and 32 on the outer circumferential surface are fastened with tape or the like to prepare the wound body 20a. The wound body 20a is taken out from the winding shaft by a take-out device (not shown). The taken-out wound body 20a is substantially cylindrical. The wound body 20a is sent to the press device 200.

[0048] <Press device 200> The press device 200 is a device that temporarily presses the wound body 20a. A known press machine or the like can be used as the press device 200. In the press device 200, the wound body 20a is pressed along a predetermined direction. In the wound body 20a, the tabs 21d and the tabs 22d, which are provided at two positions in the circumferential direction, are pressed so that they overlap each other after pressing. In this way, a flat wound body 20a is produced.

[0049] The pre-pressed wound body 20a is pressed with a stronger pressing pressure than the pre-press to produce a flat wound electrode body 20. The produced wound electrode body 20 is housed in a case, sealed, and an electrolyte is poured into it to prepare an assembly. The assembly is subjected to an initial charging process and an aging process by a known method to produce an electricity storage device 1 (see FIG. 1).

[0050] Control device 180 The control device 180 controls the processing conditions of the first laser tab cut processing device 150 and the second laser tab cut processing device 160. The control device 180 includes a memory unit 181, a first acquisition unit 182, a first calculation unit 183, a first adjustment unit 184, a second acquisition unit 185, a second calculation unit 186, a second adjustment unit 187, a third acquisition unit 188, a third calculation unit 189, and a third adjustment unit 190. The control device 180 may be, for example, a computer such as an ECU (Electronic Control Unit) or a microcomputer-mounted circuit board. The computer performs required functions according to, for example, a predetermined program. Each function of the computer is processed by the cooperation of the computer's arithmetic device (also called a processor, CPU (Central Processing Unit), or MPU (Micro-Processing Unit)) and storage device (memory, hard disk, etc.), and software.

[0051] In the manufacturing apparatus 100 for an electric storage device, the processing conditions of the first laser tab cut processing device 150 and the second laser tab cut processing device 160 are stored in a memory unit 181 of a control device 180. The trajectory L of the laser can be controlled according to the stored processing conditions. In the manufacturing apparatus 100 for an electric storage device, the processing conditions stored in the control device 180 are adjusted based on various parameters measured during and after winding of the wound body 20a.

[0052] Example 1 Fig. 6 is a block diagram showing the processing executed by control device 180. As shown in Fig. 6, manufacturing apparatus 100 for power storage devices is provided with a first tab detection device 201, a second tab detection device 202, and a rotation angle measurement device 203. First tab detection device 201 is provided on the conveyance path between first laser tab cut processing device 150 and reel 110. Second tab detection device 202 is provided on the conveyance path between second laser tab cut processing device 160 and reel 110. Rotation angle measurement device 203 is connected to reel 110.

[0053] Rotation angle measurement device 203 is a device that measures the rotation angle of reel 110 that is driven to rotate by winding device 170. Rotation angle measurement device 203 may detect the number of rotations of reel 110. There are no particular limitations on rotation angle measurement device 203 as long as it is a device that can measure the rotation angle of reel 110. For example, a rotation encoder or the like can be used as rotation angle measurement device 203. The rotation angle of reel 110 measured by rotation angle measurement device 203 is transmitted to control device 180.

[0054] The first tab detection device 201 is a device that detects the passage of the tab 21d of the conveyed positive electrode sheet 21. The second tab detection device 202 is a device that detects the passage of the tab 22d of the conveyed negative electrode sheet 22. The first tab detection device 201 will be described below. The second tab detection device 202 can be the same as the first tab detection device, so a detailed description will be omitted.

[0055] The first tab detector 201 is not particularly limited as long as it is a device that can detect the passage of the tab 21d of the conveyed positive electrode sheet 21. For example, a reflective, retroreflective, or transmissive laser sensor can be used as the first tab detector 201. In this embodiment, a retroreflective laser sensor is used as the first tab detector 201.

[0056] FIG. 7 is a schematic diagram showing the first tab detection device 201. As shown in FIG. 7, the first tab detection device 201 irradiates a laser at a position where the tab 21d passes. In the first tab detection device 201, an optical path is set so that the laser is irradiated at a predetermined position where the tab 21d passes. In FIG. 7, the optical path is set in the depth direction of the paper. When the tab 21d passes the irradiation position, the laser light is reflected by the tab 21d. The first tab detection device 201 detects the passage of the tab 21d by detecting the reflected light. When the first tab detection device 201 detects the passage of the tab 21d, the detection of the tab 21d is transmitted to the control device 180 (see FIG. 6). The tab 21d is formed at a predetermined pitch on the positive electrode sheet 21. Therefore, every time the passage of the tab 21d is detected, the detection of the tab 21d is transmitted to the control device 180.

[0057] As shown in FIG. 6, the control device 180 is configured to execute a first process S11 for acquiring the tab pitch of the positive electrode sheet 21 wound around the winding shaft 110 relative to the rotation angle of the winding shaft 110. Here, the tab pitch refers to the distance between adjacent tabs 21d along the conveyance direction. Here, the first acquisition unit 182 of the control device 180 acquires information on the passage of the tab 21d from the first tab detection device 201. In addition, the first acquisition unit 182 of the control device 180 acquires the rotation angle of the winding shaft 110 when the tab 21d passes from the rotation angle measurement device 203. Here, the first acquisition unit 182 of the control device 180 acquires the rotation angle of the winding shaft 110 when the tab 21d passes.

[0058] The control device 180 is configured to execute a second process S12 for acquiring the tab pitch of the negative electrode sheet 22 wound around the reel 110 with respect to the rotation angle of the reel 110, similar to the first process S11.

[0059] In the control device 180, the transport conditions for the positive electrode sheet 21 and the processing conditions for the tab 21d are programmed so that the tab 21d of the positive electrode sheet 21 is overlapped at a predetermined angle with respect to the reference line of the winding shaft 110. In the control device 180, the transport conditions for the negative electrode sheet 22 and the processing conditions for the tab 22d are programmed so that the tab 22d of the negative electrode sheet 22 is overlapped at a predetermined angle with respect to the reference line of the winding shaft 110.

[0060] The control device 180 is configured to execute a third process S13 for adjusting the spacing between the tabs 21d based on the tab pitch of the positive electrode sheet 21 wound around the winding shaft 110 relative to the rotation angle of the winding shaft 110 acquired in the first process S11. Similarly, the control device 180 is configured to execute a fourth process S14 for adjusting the spacing between the tabs 22d based on the tab pitch of the negative electrode sheet 22 wound around the winding shaft 110 relative to the rotation angle of the winding shaft 110 acquired in the second process S12. In the wound body 20a during winding, the position of the tab 21d moves according to the rotation angle of the winding shaft 110. The tab pitch also varies according to the number of winds. The first calculation unit 183 of the control device 180 calculates the difference between the rotation angle of the winding shaft 110 when the tab 21d passes, which is acquired during winding, and the set value of the rotation angle of the winding shaft 110 when the tab 21d passes, which is based on the programmed processing conditions and transport conditions. When there is a difference between the rotation angle of the reel 110 when the tab 21d passes, which is acquired during winding, and the set value, the first adjustment unit 184 adjusts the processing conditions of the tabs 21d, 22d stored in the storage unit 181. For example, when the tab pitch acquired at a certain rotation angle is larger than the set value, the first adjustment unit 184 can adjust the tab pitch between the tabs specified from the rotation angle to be smaller. When the tab pitch acquired at a certain rotation angle is smaller than the set value, the first adjustment unit 184 can adjust the tab pitch between the tabs specified from the rotation angle to be larger.

[0061] The control device 180 is configured to execute the first process S11 to the fourth process S14 described above. In this manner, the control device 180 feeds back the rotation angle of the winding shaft 110 and the acquired tab pitch, and adjusts the processing conditions of the tabs. This makes it easier for the tab spacing to approach the set value, and makes it easier to align the positions of the tabs 21d, 22d when the wound body 20a is wound. As a result, when the wound electrode body 20 is manufactured, the positional accuracy of the tabs 21d, 22d is improved.

[0062] By improving the positional accuracy of the tabs 21d, 22d, the tabs 21d, 22d are more likely to be aligned in the stacking direction when the electricity storage device 1 is assembled. This can improve the positional accuracy of the tabs 21d, 22d in terms of the width of the tabs 21d, 22d. As a result, the degree of freedom in designing the parts attached to the lid 12 can be improved. For example, the dimensions of the internal terminals 53, 63 can be reduced, which can lead to a reduction in manufacturing costs. This effect is significant in the electricity storage device 1 that uses the wound electrode body 20 (see FIG. 2) in which the tabs 21d, 22d protrude in the same direction.

[0063] Example 2 Fig. 8 is a block diagram showing processing executed by a control device 180 according to another embodiment. As shown in Fig. 8, the manufacturing apparatus 100 for power storage devices is provided with image inspection devices 204-206. The image inspection devices 204-206 are devices that inspect the positions of the tabs 21d, 22d of the wound electrode body 20 pressed by the press device 200. The image inspection devices 204-206 are not particularly limited as long as they are devices that can inspect the positions of the tabs 21d, 22d. As the image inspection devices 204-206, for example, an image sensor that can acquire the dimensions of a planar image can be used.

[0064] The image inspection device 204 is a device for inspecting the positive electrode tab 21d. The image inspection device 205 is a device for inspecting the negative electrode tab 22d. FIG. 9 is a schematic diagram showing the image inspection devices 204 and 205. FIG. 9 shows the positional relationship between the image inspection devices 204 and 205 and the tabs 21d and 22d as viewed along the direction in which the tabs 21d and 22d are stacked. In FIG. 9, the press device 200 is omitted.

[0065] As shown in FIG. 9, the image inspection devices 204 and 205 detect the positions of the tabs 21d and 22d of the wound body 20a in a state where the wound body 20a is temporarily pressed by the press device 200. The image inspection devices 204 and 205 obtain shape data of the tabs 21d and 22d on the surface from which the tabs 21d and 22d protrude, respectively. The imaging surfaces of the image inspection devices 204 and 205 are obliquely oriented with respect to the surface from which the tabs 21d and 22d protrude. The wound body 20a has reference positions P1 and P2 set thereon at which the outer ends of the tabs 21d and 22d are to be positioned based on the processing conditions of the tabs. The image data obtained by the image inspection devices 204 and 205 is transmitted to the control device 180.

[0066] FIG. 10 is a schematic diagram showing the image inspection device 206. FIG. 10 shows the positional relationship between the image inspection device 206 and the tabs 21d, 22d as viewed along the direction in which the tabs 21d, 22d are stacked. In FIG. 10, the imaging direction of the image inspection device 206 is set to the depth direction of the paper. As shown in FIG. 10, the wound body 20a after the provisional press is gripped by the transport chuck 200a and transported along the width direction of the tabs 21d, 22d. The image inspection device 206 detects the positions of the tabs 21d, 22d from the stacking direction (the press direction of the provisional press) of the tabs 21d, 22d extending from the wound body 20a. In this embodiment, the image inspection device 206 acquires the position data of the tabs 21d, 22d of the transported wound body 20a from above. The image data acquired by the image inspection device 206 is transmitted to the control device 180.

[0067] 8, the control device 180 is configured to execute a first process S21 for acquiring the position of the tab 21d of the positive electrode sheet 21 of the wound body 20a after it has been pressed by the press device 200. Similar to the first process S21, the control device 180 is configured to execute a second process S22 for acquiring the position of the tab 22d of the negative electrode sheet 22 of the wound body 20a after it has been pressed by the press device 200. Here, the second acquisition unit 185 of the control device 180 acquires position data of the tabs 21d, 22d from the image inspection devices 204-206.

[0068] The control device 180 is configured to execute a third process S23 for adjusting the spacing between the tabs 21d based on the position of the tabs 21d of the positive electrode sheet 21 of the wound body 20a after being pressed by the press device 200, which is acquired in the first process S21. Similarly, the control device 180 is configured to execute a fourth process S24 for adjusting the spacing between the tabs 22d based on the position of the tabs 22d of the negative electrode sheet 22 of the wound body 20a after being pressed by the press device 200, which is acquired in the second process S22. In this embodiment, the second calculation unit 186 of the control device 180 calculates the amount (length) by which the tabs 21d, 22d are shifted from the reference positions P1, P2 in the width direction.

[0069] FIG. 11 is a schematic diagram showing the wound body 20a after the provisional pressing. In FIG. 11, the positions of the tabs 21d, 22d are shown as viewed along the direction in which the tabs 21d, 22d protrude. As shown in FIG. 11, the image data acquired by the image inspection devices 204, 205 may confirm the deviation of the tabs 21d, 22d of the wound body 20a from the reference positions P1, P2. The second calculation unit 186 may calculate the amount of deviation from the reference positions P1, P2 for each of the tabs 21d, 22d. As shown in FIG. 11, when the deviations from the reference positions P1, P2 are different for each of the tabs 21d, 22d, the second calculation unit 186 may calculate the deviation of the tabs 21d, 22d based on an approximation curve. For example, the second calculation unit 186 executes a process of acquiring an approximation curve by connecting the ends (e.g., outer ends) of the tabs 21d, 22d. The second calculation unit 186 may calculate the deviations of the tabs 21d and 22d based on the approximation curve and the reference positions P1 and P2.

[0070] Further, the misalignment of the tabs 21d, 22d may be calculated along the stacking direction of the tabs 21d, 22d from the image data acquired by the image inspection device 206 (see FIG. 10). At this time, the misalignment of the tabs 21d, 22d that can be observed from above can be detected. The maximum misalignment value of the stacked tabs 21d, 22d can be calculated from the image data acquired by the image inspection device 206.

[0071] When the calculated positions of the tabs 21d, 22d are deviated from the reference positions P1, P2, the second adjustment unit 187 adjusts the processing conditions of the tabs 21d, 22d stored in the storage unit 181. For example, when the calculated positions of the tabs 21d, 22d are deviated in a direction preceding the reference positions P1, P2 with respect to the winding direction of the wound body 20a, the tab pitch can be adjusted to be smaller. When the calculated positions of the tabs 21d, 22d are deviated in a direction following the reference positions P1, P2 with respect to the winding direction of the wound body 20a, the tab pitch can be adjusted to be larger.

[0072] The control device 180 is configured to execute the first process S21 to the fourth process S24. As a result, in the control device 180, the positions of the tabs 21d, 22d of the wound body 20a after pressing are fed back, and the processing conditions of the tabs are adjusted. For example, after the sheet is wound around the reel 110 to produce the wound body 20a, the wound body 20a is pressed, and the positional deviation of the tabs 21d, 22d that may occur is easily fed back. For this reason, the processing conditions of the tabs can be adjusted in consideration of the positional deviation of the tabs 21d, 22d during pressing. As a result, the positional accuracy of the tabs 21d, 22d in the wound electrode body 20 after pressing is easily improved.

[0073] Example 3 Fig. 12 is a block diagram showing processing executed by a control device 180 according to another embodiment. As shown in Fig. 12, the manufacturing apparatus 100 for an electricity storage device is provided with thickness inspection devices 207-210. The thickness inspection devices 207-210 are devices that measure the thickness of the positive electrode sheet 21, the negative electrode sheet 22, and the separators 31 and 32 that are being conveyed, respectively. The thickness inspection devices 207-210 are not particularly limited as long as they are devices that can inspect the thickness of each sheet. For example, a non-contact type laser displacement meter can be used as the thickness inspection devices 207-210.

[0074] FIG. 13 is a schematic diagram showing a thickness inspection device 207. In FIG. 13, the thickness inspection device 207 and the positive electrode sheet 21 are shown as viewed along the direction in which the positive electrode sheet 21 is transported. As shown in FIG. 13, the thickness inspection device 207 is arranged so that a laser can be irradiated substantially perpendicularly to the positive electrode sheet 21. The thickness inspection device 207 irradiates a laser onto the unformed region 21a3 of the positive electrode current collector foil 21a and the surface of the positive electrode active material layer 21b formed on the positive electrode current collector foil 21a. The thickness inspection device 207 detects the light reflected from the unformed region 21a3 and the surface of the positive electrode active material layer 21b, and measures the thickness of the positive electrode active material layer 21b. The thickness inspection device 207 can continuously measure the thickness of the positive electrode active material layer 21b. In this embodiment, the thickness inspection device 207 is provided at a position along a guide roller (not shown) where the thickness of the positive electrode sheet 21 can be measured. By measuring the thickness of the positive electrode sheet 21 while it is aligned with the guide rollers, deviation in the thickness direction is suppressed, and the measurement accuracy of the thickness of the positive electrode sheet 21 can be improved.

[0075] A thickness inspection device 208 (see FIG. 12) that inspects the thickness of the negative electrode active material layer 22b of the negative electrode sheet 22 can be similar to the thickness inspection device 207, so a detailed description will be omitted. The thickness inspection devices 209, 210 (see FIG. 12) measure the thicknesses of the separators 31, 32. The measured thicknesses of the positive electrode active material layer 21b and the negative electrode active material layer 22b are transmitted to the control device 180.

[0076] 12, the control device 180 is configured to execute a first process S31 for acquiring the thickness of the positive electrode sheet 21 wound around the reel 110. Similar to the first process S31, the control device 180 is configured to execute a second process S32 for acquiring the thickness of the negative electrode sheet 22 wound around the reel 110. Here, a third acquisition unit 188 of the control device 180 acquires data on the thicknesses of the positive electrode sheet 21, the negative electrode sheet 22, and the separators 31, 32 from the thickness inspection devices 207-210.

[0077] The control device 180 is configured to execute a third process S33 of adjusting the spacing between the tabs 21d based on the thickness of the positive electrode sheet 21 to be wound around the reel 110, obtained in the first process S31. Similarly, the control device 180 is configured to execute a fourth process S34 of adjusting the spacing between the tabs 22d based on the thickness of the negative electrode sheet 22 to be wound around the reel 110, obtained in the second process S32. In this embodiment, a third calculation unit 189 of the control device 180 calculates the difference between the obtained thickness of each sheet and a reference thickness.

[0078] Here, the reference thickness refers to the set value of the thickness of each sheet when the wound body 20a is produced. The prepared sheets may have thickness variations in the plane. For example, the positive electrode active material layer 21b and the negative electrode active material layer 22b may be formed by applying a slurry to the substrate (positive electrode current collector foil 21a and negative electrode current collector foil 22a) and drying the slurry. For this reason, the positive electrode sheet 21 and the negative electrode sheet 22 may have thickness variations. In addition, the thicknesses of the positive electrode current collector foil 21a, the negative electrode current collector foil 22a, and the separators 31 and 32 are not necessarily constant. When there is thickness variation in the length direction of the sheets, the length wound around the reel 110 may change. For example, when the thickness of the sheet is thinner than the reference thickness, the outer diameter of the wound body 20a wound around the reel 110 becomes smaller. As a result, the positions of the tabs 21d and 22d may be shifted to positions preceding the above-mentioned predetermined positions. When the thickness of the sheet is greater than the reference thickness, the outer diameter of the wound body 20a wound around the reel 110 increases, which can cause the positions of the tabs 21d and 22d to shift to positions behind the predetermined angle.

[0079] The third calculation unit 189 of the control device 180 can calculate the deviation of the tabs 21d, 22d based on the difference between the acquired thickness of each sheet and the reference thickness. The third adjustment unit 190 adjusts the processing conditions of the tabs 21d, 22d stored in the storage unit 181. For example, when the calculated sheet thickness is thicker than the reference thickness, the tab pitch can be adjusted to be larger. When the calculated sheet thickness is thinner than the reference thickness, the tab pitch can be adjusted to be smaller.

[0080] The control device 180 is configured to execute the first process S31 to the fourth process S34. In this way, in the control device 180, information on the thickness of the sheet before winding is fed back, and the processing conditions of the tabs are adjusted. For example, when there is a difference in the tendency between the sheet thickness and the reference thickness for each production lot, the processing conditions for winding the sheet of the same production lot may be adjusted. This can improve the positional accuracy of the wound body 20a after winding. In addition, the pitch of the tabs 21d, 22d in the sheet during winding may be adjusted according to the thickness of the sheet. This can reduce the deviation of the positions of the tabs 21d, 22d caused by the variation in the thickness of the sheet. As a result, the positional accuracy of the tabs 21d, 22d after winding can be improved even in the wound body 20a during winding.

[0081] Example 4 FIG. 14 is a block diagram showing a process executed by a control device 180 according to another embodiment. As shown in FIG. 14, the manufacturing apparatus 100 for power storage devices is provided with a first tab detection device 201, a second tab detection device 202, and a rotation angle measurement device 203, similar to the first embodiment. The manufacturing apparatus 100 for power storage devices is further provided with image inspection devices 204 to 206, similar to the second embodiment. The control device 180 is configured to execute a first process S41 to an eighth process S48. Here, the first process S41 to a fourth process S44 are similar to the first process S11 to a fourth process S14 in the first embodiment, and the fifth process S45 to an eighth process S48 are similar to the first process S21 to a fourth process S24 in the second embodiment.

[0082] In the power storage device manufacturing apparatus 100, the rotation angle of the winding shaft 110 and the acquired tab pitch are fed back by the first process S41 to the fourth process S44 executed by the control device 180, and the processing conditions for the tabs are adjusted. Furthermore, the positions of the tabs 21d, 22d of the wound body 20a after pressing are fed back by the fifth process S45 to the eighth process S48, and the processing conditions for the tabs are adjusted. This not only makes it easier for the spacing between the tabs to approach the set value, but also makes it easier to improve the positional accuracy of the tabs 21d, 22d in the wound electrode body 20 after winding and pressing. As a result, the positional accuracy of the tabs 21d, 22d can be further improved.

[0083] Example 5 FIG. 15 is a block diagram showing a process executed by a control device 180 according to another embodiment. As shown in FIG. 15, a manufacturing apparatus 100 for an electric storage device is provided with a first tab detection device 201, a second tab detection device 202, and a rotation angle measurement device 203, similar to the first embodiment. A manufacturing apparatus 100 for an electric storage device is further provided with thickness inspection devices 207-210, similar to the third embodiment. The control device 180 is configured to execute a first process S51 to an eighth process S58. Here, the first process S51 to a fourth process S54 are similar to the first process S11 to a fourth process S14 of the first embodiment, and the fifth process S55 to an eighth process S58 are similar to the first process S31 to a fourth process S34 of the third embodiment.

[0084] In the power storage device manufacturing apparatus 100, the rotation angle of the winding shaft 110 and the acquired tab pitch are fed back by the first process S51 to the fourth process S54 executed by the control device 180, and the tab processing conditions are adjusted. Furthermore, information on the thickness of the sheet before winding is fed back by the fifth process S55 to the eighth process S58, and the tab processing conditions are adjusted. This not only makes it easier for the tab spacing to approach the set value, but also reduces positional deviations of the tabs 21d, 22d caused by variations in the sheet thickness. As a result, the positional accuracy of the tabs 21d, 22d can be further improved.

[0085] Example 6 FIG. 16 is a block diagram showing processing executed by a control device 180 according to another embodiment. As shown in FIG. 16, the power storage device manufacturing apparatus 100 is provided with image inspection devices 204-206, similar to Example 2. The power storage device manufacturing apparatus 100 is further provided with thickness inspection devices 207-210, similar to Example 3. The control device 180 is configured to execute a first process S61 to an eighth process S68. Here, the first process S61 to a fourth process S64 are similar to the first process S21 to the fourth process S24 of Example 2, and the fifth process S65 to the eighth process S68 are similar to the first process S31 to the fourth process S34 of Example 3.

[0086] In the manufacturing apparatus 100 for an electricity storage device, the first process S61 to the fourth process S64 executed by the control device 180 feed back the positions of the tabs 21d, 22d of the wound body 20a after pressing, and the processing conditions for the tabs are adjusted. Furthermore, the fifth process S65 to the eighth process S68 feed back information on the thickness of the sheet before winding, and the processing conditions for the tabs are adjusted. This not only reduces the deviation of the positions of the tabs 21d, 22d caused by variations in the thickness of the sheet, but also makes it easier to improve the positional accuracy of the tabs 21d, 22d in the wound electrode body 20 after winding and pressing. As a result, the positional accuracy of the tabs 21d, 22d can be further improved.

[0087] Example 7 Fig. 17 is a block diagram showing processing executed by a control device 180 according to another embodiment. As shown in Fig. 17, the power storage device manufacturing apparatus 100 is provided with a first tab detection device 201, a second tab detection device 202, and a rotation angle measurement device 203, similar to Example 1. The power storage device manufacturing apparatus 100 is further provided with image inspection devices 204 to 206, similar to Example 2. The power storage device manufacturing apparatus 100 is further provided with thickness inspection devices 207 to 210, similar to Example 3. The control device 180 is configured to execute a first process S71 to a twelfth process S82. Here, the first process S71 to the fourth process S74 are similar to the first process S11 to the fourth process S14 in the first embodiment, the fifth process S75 to the eighth process S78 are similar to the first process S21 to the fourth process S24 in the second embodiment, and the ninth process S79 to the twelfth process S82 are similar to the first process S31 to the fourth process S34 in the third embodiment.

[0088] In the manufacturing apparatus 100 for the electric storage device, the first process S71 to the fourth process S74 executed by the control device 180 feed back the rotation angle of the winding shaft 110 and the acquired tab pitch, and adjust the processing conditions of the tabs. In addition, the fifth process S75 to the eighth process S78 feed back the positions of the tabs 21d, 22d of the wound body 20a after pressing, and adjust the processing conditions of the tabs. Furthermore, the ninth process S79 to the twelfth process S82 feed back information on the thickness of the sheet before winding, and adjust the processing conditions of the tabs. This makes it easier for the spacing between the tabs to approach the set value, and can reduce the deviation of the positions of the tabs 21d, 22d caused by the variation in the thickness of the sheet. Furthermore, after winding, the positional accuracy of the tabs 21d, 22d in the wound electrode body 20 after pressing can be improved. As a result, the positional accuracy of the tabs 21d, 22d can be further improved.

[0089] In this embodiment, the processing conditions of the tabs are adjusted based on the tab pitch (variable 1) of the sheets 21 and 22 before winding acquired in the first and second processes S71 and S72, the positions of the tabs 21d and 22d after pressing acquired in the fifth and sixth processes S75 and S76, and the thickness (variable 4) of the sheets 21, 22, 31, and 32 acquired in the ninth and tenth processes S79 and S80. The tab pitch of the sheets 21 and 22 before winding, the positions of the tabs 21d and 22d after pressing, and the thicknesses of the sheets 21, 22, 31, and 32 may be weighted and reflected in the processing conditions of the tabs. Here, the positions of the tabs 21d and 22d calculated from the image inspection devices 204 and 205 are set as variable 2, and the positions of the tabs 21d and 22d calculated from the image inspection device 206 are set as variable 3.

[0090] For example, weighting coefficients W1 to W4 may be assigned to variables 1 to 4. The weighting coefficients W1 to W4 may be set so that the sum of the weighting coefficients W1 to W4 is 1. The tab pitch correction value for adjusting the processing conditions of the tabs may be expressed based on the following formula. Tab pitch correction value = W1 x variable 1 + W2 x variable 2 + W3 x variable 3 + W4 x variable 4 The weighting coefficients W1 to W4 can be appropriately set according to product specifications, processing conditions, etc. Therefore, the weighting coefficients W1 to W4 may be determined based on data accumulated during production, testing, etc.

[0091] From the viewpoint of stabilizing the position of the tab, the processing of the tab may be continuously performed on the sheet that is continuously transported at a constant speed. For example, a sheet without a tab may be transported from the unwinding roll to the winding roll, and the tab may be formed on the sheet on the transport path. In this way, a roll on which the sheet with the tab formed is wound may be prepared. According to the trial of the present inventor, when the tab processing is stopped every time the wound body is produced, such as when the tab processing is performed during the winding of the wound body, the position of the tab may be shifted. However, according to the manufacturing apparatus 100 for the electricity storage device disclosed herein, the positions of the tabs 21d, 22d, etc. can be fed back to the processing conditions of the tabs every time the wound body 20a is produced. The processing conditions of the tabs 21d, 22d are adjusted according to the winding conditions when the wound body 20a is wound. This makes it easy to improve the positional accuracy of the tabs 21d, 22d even when the sheet transport and the tab processing are intermittent operations.

[0092] The technology disclosed herein has been described above in various ways. Unless otherwise specified, the embodiments given herein do not limit the present invention. The order of the first to twelfth processes executed by the control device described above is not particularly limited, and may be changed as appropriate according to the manufacturing process of the power storage device. Furthermore, the technology disclosed herein may be changed in various ways, and each component or each process mentioned herein may be omitted or combined as appropriate, as long as no particular problem occurs. [Explanation of symbols]

[0093] 1. Energy storage devices 10 Cases 11 Case body 11f opening 12 Lid 12a, 12b Mounting holes 12c Liquid injection hole 12d Gas exhaust valve 12e Sealing member 20 Wound electrode body 20a Winding body 21 Positive electrode sheet 21a Positive electrode current collector foil 21a1,22a1 1st edge 21a2,22a2 2nd edge 21a3,22a3 Unformed area 21b Positive electrode active material layer 21c protective layer 21d,22d Tab 22 Negative electrode sheet 22a Negative current collector foil 22b Negative electrode active material layer 31,32 Separator 50 Positive terminal 51,61 External connection part 52,62 Shaft 53,63 Internal terminal 60 Negative terminal 70 Insulator 80 Gasket 90 Insulation sheet 100 Manufacturing equipment for power storage devices 110 Roll 111 Slit 120 First conveying device 122, 132, 142, 143 Unwinding shaft 124 Positive electrode roll 130 Second conveying device 134 Negative electrode roll 140,141 Third conveying device 144,145 Separator roll 170 Winding device 180 Control device 181 Storage section 182 First acquisition part 183 First Calculation Section 184 1st adjustment section 185 Second Acquisition Department 186 Second Calculation Section 187 2nd adjustment section 188 Third Acquisition Department 189 Third Calculation Section 190 3rd adjustment section 200 Press equipment 200a Transport chuck 203 Rotational Angle Measurement Device 204~206 Image inspection equipment 207~210 Thickness inspection device G interval L locus

Claims

1. A reel; a first conveying device that conveys a strip-shaped positive electrode sheet toward the winding shaft; a first laser tab cut processing device that forms tabs at predetermined intervals on the positive electrode sheet transported by the first transport device; a second conveying device that conveys the band-shaped negative electrode sheet toward the winding shaft; a second laser tab cut processing device that forms tabs at predetermined intervals on the negative electrode sheet transported by the second transport device; a winding device that rotates the winding shaft and winds up the positive electrode sheet on which a tab has been formed by the first laser tab cut processing device and the negative electrode sheet on which a tab has been formed by the second laser tab cut processing device; Control device and Equipped with the positive electrode sheet has a band-shaped positive electrode current collector foil and a positive electrode active material layer formed in an area of ​​the band-shaped positive electrode current collector foil excluding an unformed area set in a first edge portion in a width direction, the negative electrode sheet has a band-shaped negative electrode current collector foil and a negative electrode active material layer formed in a region of the band-shaped negative electrode current collector foil excluding an unformed region set in a first edge portion in a width direction, The control device includes: a first process of acquiring a tab pitch of the positive electrode sheet wound around the winding shaft with respect to a rotation angle of the winding shaft; A second process of acquiring a tab pitch of the negative electrode sheet wound around the winding shaft with respect to a rotation angle of the winding shaft; a third process in which the first laser tab cut processing device adjusts the spacing between the tabs formed on the positive electrode sheet based on the tab pitch of the positive electrode sheet wound around the winding shaft relative to the rotation angle of the winding shaft acquired in the first process; a fourth process in which the second laser tab cut processing device adjusts the spacing between the tabs formed on the negative electrode sheet based on the tab pitch of the negative electrode sheet wound around the winding shaft relative to the rotation angle of the winding shaft acquired in the second process; and configured to run, Manufacturing equipment for energy storage devices.

2. The winding body removed from the winding shaft is further provided with a press device. The control device includes: a fifth process of acquiring a position of a tab of the positive electrode sheet of the wound body after the positive electrode sheet has been pressed by a press device; A sixth process of acquiring a position of a tab of the negative electrode sheet of the wound body after the negative electrode sheet has been pressed by a press device; a seventh process in which the first laser tab cut processing device adjusts the spacing between the tabs formed on the positive electrode sheet based on the positions of the tabs of the positive electrode sheet of the wound body after being pressed by the press device, the positions being acquired in the fifth process; an eighth process in which the second laser tab cut processing device adjusts the spacing between the tabs formed on the negative electrode sheet based on the positions of the tabs of the negative electrode sheet of the wound body after being pressed by the press device, the positions being acquired in the sixth process; The manufacturing apparatus for an electricity storage device according to claim 1 , further configured to execute the following:

3. The control device includes: A ninth process of acquiring a thickness of the positive electrode sheet wound around the winding shaft; A tenth process of acquiring a thickness of the negative electrode sheet wound around the winding shaft; an eleventh process in which the first laser tab cut processing device adjusts an interval between tabs formed in the unformed area of ​​the positive electrode sheet based on a thickness of the positive electrode sheet wound around the winding shaft relative to a rotation angle of the winding shaft obtained in the ninth process; a twelfth process in which the second laser tab cut processing device adjusts the interval between tabs formed in the unformed area of ​​the negative electrode sheet based on the thickness of the negative electrode sheet to be wound around the winding shaft relative to the rotation angle of the winding shaft obtained in the tenth process; The manufacturing apparatus for an electricity storage device according to claim 1 or 2, further configured to execute the following:

4. A reel; a first conveying device that conveys a strip-shaped positive electrode sheet toward the winding shaft; a first laser tab cut processing device that forms tabs at predetermined intervals on the positive electrode sheet transported by the first transport device; a second conveying device that conveys the band-shaped negative electrode sheet toward the winding shaft; a second laser tab cut processing device that forms tabs at predetermined intervals on the negative electrode sheet transported by the second transport device; a winding device that rotates the winding shaft and winds up the positive electrode sheet on which a tab has been formed by the first laser tab cut processing device and the negative electrode sheet on which a tab has been formed by the second laser tab cut processing device; a press device that presses the wound body removed from the winding shaft; Control device and Equipped with the positive electrode sheet has a band-shaped positive electrode current collector foil and a positive electrode active material layer formed in an area of ​​the band-shaped positive electrode current collector foil excluding an unformed area set in a first edge portion in a width direction, the negative electrode sheet has a band-shaped negative electrode current collector foil and a negative electrode active material layer formed in a region of the band-shaped negative electrode current collector foil excluding an unformed region set in a first edge portion in a width direction, The control device includes: a first process of acquiring a position of a tab of the positive electrode sheet of the wound body after the positive electrode sheet has been pressed by a press device; a second process of acquiring a position of a tab of the negative electrode sheet of the wound body after the wound body has been pressed by a press device; a third process in which the first laser tab cut processing device adjusts the spacing of the tabs formed on the positive electrode sheet based on the positions of the tabs of the positive electrode sheet of the wound body after being pressed by the press device, the positions being acquired in the first process; a fourth process in which the second laser tab cut processing device adjusts the spacing between the tabs formed on the negative electrode sheet based on the position of the tabs of the negative electrode sheet of the wound body after being pressed by the press device, the position being acquired in the second process; configured to run, Manufacturing equipment for energy storage devices.

5. The control device includes: A fifth process of acquiring a thickness of the positive electrode sheet wound around the winding shaft; A sixth process of acquiring a thickness of the negative electrode sheet wound around the winding shaft; a seventh process in which the first laser tab cut processing device adjusts an interval between tabs formed in the unformed area of ​​the positive electrode sheet based on a thickness of the positive electrode sheet to be wound around the winding shaft relative to a rotation angle of the winding shaft obtained in the fifth process; and an eighth process in which the second laser tab cut processing device adjusts the interval between tabs formed in the unformed area of ​​the negative electrode sheet based on the thickness of the negative electrode sheet to be wound around the winding shaft relative to the rotation angle of the winding shaft obtained in the sixth process; The apparatus for manufacturing an electricity storage device according to claim 4 , further configured to execute the following:

6. A reel; a first conveying device that conveys a strip-shaped positive electrode sheet toward the winding shaft; a first laser tab cut processing device that forms tabs at predetermined intervals on the positive electrode sheet transported by the first transport device; a second conveying device that conveys the band-shaped negative electrode sheet toward the winding shaft; a second laser tab cut processing device that forms tabs at predetermined intervals on the negative electrode sheet transported by the second transport device; a winding device that rotates the winding shaft and winds up the positive electrode sheet on which a tab has been formed by the first laser tab cut processing device and the negative electrode sheet on which a tab has been formed by the second laser tab cut processing device; Control device and Equipped with the positive electrode sheet has a band-shaped positive electrode current collector foil and a positive electrode active material layer formed in an area of ​​the band-shaped positive electrode current collector foil excluding an unformed area set in a first edge portion in a width direction, the negative electrode sheet has a band-shaped negative electrode current collector foil and a negative electrode active material layer formed in a region of the band-shaped negative electrode current collector foil excluding an unformed region set in a first edge portion in a width direction, The control device includes: A first process of acquiring a thickness of the positive electrode sheet wound around the winding shaft; A second process of acquiring a thickness of the negative electrode sheet wound around the winding shaft; a third process in which the first laser tab cut processing device adjusts an interval between tabs formed in the unformed area of ​​the positive electrode sheet based on a thickness of the positive electrode sheet to be wound around the winding shaft relative to a rotation angle of the winding shaft obtained in the first process; a fourth process in which the second laser tab cut processing device adjusts the spacing between tabs formed in the unformed area of ​​the negative electrode sheet based on the thickness of the negative electrode sheet to be wound around the winding shaft relative to the rotation angle of the winding shaft obtained in the second process; and configured to run, Manufacturing equipment for energy storage devices.

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