Method for manufacturing an energy storage device and apparatus for manufacturing the same.

Abstract

To provide a method for manufacturing a power storage device with which the breakage of a current collector foil is prevented.SOLUTION: A manufacturing method 1 for power storage devices is a method for manufacturing a power storage device which is created by encapsulating in a film-like outer package 20 a laminate 10 that comprises a laminate body 11 which is formed by laminating sheet-like cathodes and anodes together with a separator and a plurality of extended current collector foils 12 that are extended outward from the laminate body 11 and stacked one on top of another in the laminate direction, the manufacturing method including a weld step, a seal step, and a degassing step. In the weld step, a pressing jig 50 is pressed against a region 122 between a scheduled weld position 121 in the stacked extended current collector foils 12 and the laminate body 11 so as to deform the extended current collector foils 12 to a desired shape, and then the plurality of extended current collector foils 12 are welded to each other at the scheduled weld position 121. In the seal step, the laminate 10 is covered with the outer package 20 and the outer circumference of the laminate 10 in the outer package 20 is sealed. In the degassing step, a gas is vented from the inside of the sealed outer package 20.SELECTED DRAWING: Figure 4

Description

Technical Field

[0001] The present invention relates to a method for manufacturing a power storage device and a manufacturing apparatus therefor.

Background Art

[0002] Conventionally, in a power storage device obtained by enclosing a laminate formed by laminating a plurality of sheet-shaped positive electrodes and negative electrodes together with a separator in a film-shaped exterior body, each positive electrode and each negative electrode are provided with an extended current collecting foil that extends outward in a plan view. The extended current collecting foils are overlapped and welded to each other for each positive electrode and each negative electrode in the laminate. As an example of a method for manufacturing such a power storage device, in the method disclosed in Patent Document 1, after welding each pair of extended current collecting foils in the laminate, the extended current collecting foil between the laminate body and the welded portion is pressed in the thickness direction from the outside of the exterior body, and the exterior body is welded while in the pressed state. Thereby, it is possible to suppress the exterior body from being partially peeled off.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] However, in the method disclosed in Patent Document 1, in each extended current collector foil, the region between the laminate body and the welded portion where the extended current collector foils are welded together is fixed and constrained at both ends, i.e., the position connected to the laminate body and the position of the welded portion. Therefore, when the region between the laminate body and the welded portion of the extended current collector foil is pressed, the extended current collector foil deforms irregularly and becomes crushed, causing excessive stress on the extended current collector foil and potentially leading to fracture. Alternatively, instead of the method disclosed in Patent Document 1, it is also conceivable to weld each extended current collector foil to each other in the laminate, and then weld an outer casing without pressing the region between the laminate body and the welded portion, and then vent the gas from the inside of the outer casing. In this case, the extended current collector foil is pressed by the outer casing when it is welded, and during venting, the outer casing shrinks and conforms to the shape of the laminate surface, causing the extended current collector foil to be pressed by the outer casing. Therefore, in this case as well, the extended current collector foil may deform irregularly and become crushed in the region between the laminate body and the welded joint between the current collector foils, potentially causing excessive stress and fracture.

[0005] This invention has been made in view of the above problems, and aims to provide a method for manufacturing an energy storage device and an apparatus for manufacturing the same in which damage to the extended current collector foil is prevented. [Means for solving the problem]

[0006] One aspect of the present invention relates to a method for manufacturing an energy storage device, comprising a laminate body comprising a laminate body formed by laminating sheet-shaped positive and negative electrodes together with a separator, and a plurality of extended current collector foils extending outward from the laminate body and overlapping in the lamination direction, the laminate body being enclosed in a film-like outer casing. A pressing jig is placed in the region between the planned welding position in the overlapping extended current collector foil and the laminate body. tip A welding process in which the extended current collector foils are welded together at the planned welding position while being pressed to deform the extended current collector foils into the target shape, A sealing step in which the laminate is covered with the outer casing and the outer periphery of the laminate is sealed by the outer casing, A gas venting process is performed to release gas from the inside of the sealed exterior body, Includes fruit, The above target shape is a shape that follows the inner surface of the outer casing of the completed energy storage device. The tip of the above pressing jig has a curved shape that conforms to the inner surface of the outer casing of the completed energy storage device. In the above degassing process, the gas inside the outer casing is removed to the outside of the outer casing by the degassing process, thereby pressing the outer casing against the extended current collector foil that has been deformed into the target shape. It lies in the manufacturing method of energy storage devices.

[0007] Furthermore, other embodiments of the present invention include: A manufacturing apparatus for an energy storage device, comprising a laminate body comprising a laminate body formed by laminating sheet-shaped positive and negative electrodes together with a separator, and a plurality of extended current collector foils extending outward from the laminate body and overlapping in the lamination direction, the laminate body being enclosed in a film-like outer casing, the above A support base for supporting the laminate, A welding apparatus for welding the overlapping extended current collector foils to each other at the planned welding position, Provided between the above-mentioned support base and the above-mentioned welding apparatus, before or simultaneously with the above-mentioned welding, At the tip A pressing jig that presses on the area of ​​the extended current collector foil that is closer to the laminate body than the planned welding position to deform it into the target shape, A suction device that covers the laminate and seals the outer periphery of the laminate, and vents gas from the inside of the outer casing, Equipped with, The above target shape is a shape that follows the inner surface of the outer casing of the completed energy storage device. The tip of the above pressing jig has a curved shape that conforms to the inner surface of the outer casing of the completed energy storage device. The welding apparatus, by pressing the tip of the pressing jig onto the extended current collector foil, deforms the extended current collector foil into the target shape, and then welds the overlapping extended current collector foils together at the planned welding position. The above-mentioned suction device is part of a manufacturing apparatus for an energy storage device, which presses the outer casing against the extended current collector foil that has been deformed into the target shape by removing the gas inside the outer casing to the outside of the outer casing through the above-mentioned degassing. [Effects of the Invention]

[0008] In the manufacturing method of the energy storage device according to the above embodiment, when welding the current collector foils together, a pressing jig is pressed against the current collector foil between the planned welding position and the laminate to deform the current collector foil into the target shape. Therefore, when pressing the current collector foil with the pressing jig, the foils are not welded to each other, so the pressing of the pressing jig can deform the current collector foil into a smooth shape that conforms to the target shape without crushing it. As a result, excessive stress on the current collector foil is suppressed, and the fracture of the current collector foil is prevented. Furthermore, when covering the laminate with an outer casing or when venting gas from inside the outer casing, the current collector foil has already been molded into the target shape, so even if the outer casing presses against the current collector foil, excessive stress on the current collector foil is suppressed, and the fracture of the current collector foil is prevented.

[0009] Furthermore, in the manufacturing apparatus for the other embodiment of the energy storage device described above, the current collector foil can be deformed into the target shape by pressing a pressing jig on an area of ​​the laminate closer to the planned welding position, and then welded at the planned welding position by a welding device simultaneously with or at the same time as the deformation. As a result, the current collector foil can be deformed into a smooth shape that conforms to the target shape without being crushed by the pressing jig, thereby suppressing excessive stress on the current collector foil and preventing fracture of the current collector foil.

[0010] As described above, according to the above embodiment, it is possible to provide a method for manufacturing an energy storage device in which damage to the current collector foil is prevented. [Brief explanation of the drawing]

[0011] [Figure 1] (a) Front view of the energy storage device in Embodiment 1, and (b) Enlarged cross-sectional view at the position of line Ib-Ib in Figure (a). [Figure 2] Flowchart of the manufacturing method for the energy storage device in Embodiment 1. [Figure 3] (a) Front view of the laminate in Embodiment 1, and (b) Enlarged cross-sectional view at the position of line IIIb-IIIb in Figure (a). [Figure 4] An enlarged cross-sectional view at the position corresponding to line IIIb-IIIb in Figure 3(a) for illustrating the welding processes (a) and (b) in Embodiment 1. [Figure 5] Another enlarged cross-sectional view at the position corresponding to line IIIb-IIIb in FIG. 3(a) for explaining the (a) and (b) welding processes in Embodiment 1. [Figure 6] Another enlarged cross-sectional view at the position corresponding to line IIIb-IIIb in FIG. 3(a) for explaining the processes after the (a) welding process in Embodiment 1, and (b) a front view of the laminate after welding. [Figure 7] (a) Front view and (b) side view for explaining the sealing process and the gas venting process in Embodiment 1. [Figure 8] Enlarged cross-sectional views at the position corresponding to line IIIb-IIIb in FIG. 3(a) for explaining the (a), (b), and (c) sealing processes and the gas venting process in Embodiment 1.

Mode for Carrying Out the Invention

[0012] (Embodiment 1) An embodiment of the manufacturing method 1 of the power storage device 100 and its manufacturing apparatus 200 will be described with reference to FIGS. 1 to 8. First, the power storage device 100 in the present Embodiment 1 will be described in detail below. The energy storage device 100 includes capacitors and secondary batteries, and in this embodiment, as shown in Figure 1(a), a lithium-ion capacitor is employed, in which a laminate 10 is sealed in an outer casing 20 together with an electrolyte solution using a lithium salt as the electrolyte. The external shape of the energy storage device 100 is a flat rectangular shape, with the laminate 10 enclosed in the outer casing 20 in its central part. As shown in Figure 1(b), the laminate 10 comprises a laminate body 11 formed by laminating sheet-shaped positive electrodes 11a and negative electrodes 11b via a separator 11c, and a plurality of extended current collector foils 12 and 13 that extend outward from the laminate body 11 and are stacked in the lamination direction. The laminate body 11 corresponds to the region where active material is provided in the positive electrode 11a and negative electrode 11b. Each of the plurality of extended current collector foils 12 is connected to the positive electrode 11a, and although not shown, each of the plurality of extended current collector foils 13 is connected to the negative electrode 11b. As shown in Figure 1(a), current collection tabs 21 and 22 connected to the extended current collection foils 12 and 13 are provided protruding outward from one side of the energy storage device 100 in the width direction X. In this embodiment 1, the direction parallel to the long side in a plan view of the laminate 10 is defined as the width direction X, and the direction parallel to the short side is defined as the depth direction Y. The direction parallel to the lamination direction of the laminate 10 is defined as the thickness direction Z.

[0013] As shown in Figure 1(b), in the completed energy storage device 100, the outermost (front and back) outermost current collector foil 12a of the multiple extended current collector foils 12 in the thickness direction Z has a shape that conforms to the shape of the inner surface 23 of the outer casing 20 that is opposite to the side of the laminate body 11 from which the extended current collector foil 12 extends. In this embodiment 1, in the manufacturing method 1 described later, the shape of the inner surface 23 of the outer casing is set as the target shape of the outer extended current collector foil 12a. The inner extended current collector foil 12b, which is located inside the outermost outer extended current collector foil 12a of the multiple extended current collector foils 12, has an end on the side connected to the laminate body 11 at a position where it is equally spaced in the thickness direction Z, and the opposite end is at a position where they are welded together (a position that coincides with the planned welding position 121), and has a shape that smoothly connects the two ends in an S-shape. In this embodiment 1, in the manufacturing method 1 described later, each of the smoothly connected S-shaped forms is set as the target shape for each inner extended current collector foil 12b.

[0014] The manufacturing method 1 for the energy storage device 100 of this embodiment 1 will be described in detail below. As shown in Figure 2, the manufacturing method 1 for the energy storage device 100 includes a welding step S2, a sealing step S3, and a degassing step S5. In this embodiment 1, the manufacturing method includes a laminate preparation step S1 before the welding step S2, an initial charging step S4 after the sealing step S3, and a resealing step S6 and a cutting step S7 after the degassing step S5.

[0015] First, in the laminate preparation step S1, the laminate 10 shown in Figure 3(a) is prepared. The laminate 10 before assembly in the laminate preparation step S1 has, as shown in Figure 3(b), a laminate body 11 formed by laminating sheet-shaped positive electrodes 11a and negative electrodes 11b together with a separator 11c, and a plurality of extended current collector foils 12 and 13 protruding outward from the laminate body 11. As shown in Figures 3(a) and 3(b), the plurality of extended current collector foils 12 are connected to the positive electrodes 11a and are aligned and overlapped with each other. The plurality of extended current collector foils 13 are connected to the negative electrodes 11b and are aligned and overlapped with each other. In this embodiment, lithium ions are pre-doped into the negative electrodes 11b. Then, as shown in Figure 4(a), the prepared laminate 10 is placed on the support base 60 of the manufacturing apparatus 200, which will be described later.

[0016] Next, in welding step S2, as shown in Figures 4(a) and 4(b), the pressing jig 50 is pressed onto the region 122 between the planned welding position 121 and the laminate body 11 of the overlapping extended current collector foils 12 to deform each of the multiple extended current collector foils 12 into the target shape described above. This sets each of the multiple extended current collector foils 12 to conform to their respective target shapes. Then, as shown in Figure 5(a), with each of the multiple extended current collector foils 12 deformed into their respective target shapes, the multiple extended current collector foils 12 are welded together at the planned welding position 121. Although not shown, similarly, with the multiple overlapping extended current collector foils 13, the pressing jig 50 is pressed onto the region 132 between the planned welding position 131 and the laminate body 11 to deform each of them into their respective target shapes, and then the multiple extended current collector foils 13 are welded together at the planned welding position 131.

[0017] As shown in Figure 4(a), the pressing jig 50 consists of a base plate 51 and a resin plate 52. The base plate 51 is made of metal and the resin plate 52 is attached to it so that its position can be adjusted. The resin plate 52 is made of resin and its tip 52a is configured to press against a plurality of extended current collector foils 12 and 13. In this embodiment 1, during the welding process S2, a pair of pressing jigs 50 are provided so as to sandwich the extended current collector foils 12 and 13 of the laminate 10 placed on the support base 60 in the thickness direction Z of the laminate 10, and the pressing jigs 50 are movable toward the extended current collector foils 12 and 13. In this embodiment 1, the pair of pressing jigs 50 are configured to press the extended current collector foils 12 and 13 to the central position in the thickness direction Z of the laminate 10. Note that the position in which the pressing jigs 50 press against the extended current collector foils 12 and 13 is not limited to this and can be changed as appropriate to match the target shape described above.

[0018] In this embodiment 1, as shown in Figure 4(a), the tip 52a of the resin plate 52 has a curved cross-sectional shape perpendicular to the depth direction Y in the laminate 10, which conforms to the shape of the inner surface 23 of the outer casing shown in Figure 1(b) (i.e., the target shape of the outer extended current collector foil 12a). In this embodiment 1, the tip 52a of the resin plate 52 is configured to contact and directly press the extended current collector foils 12 and 13 by moving the base plate 51 and the resin plate 52 toward the extended current collector foils 12 and 13. Note that in this cross-section, the tip 52a has a curved shape conforming to the target shape on the side facing the support base 60, while the side opposite the support base 60 may have a different shape from the target shape. The amount of movement of the base plate 51 and the resin plate 52 when pressing the extended current collector foils 12 and 13 can be appropriately set considering the target shape, the shape of the laminate 10, the thickness of the extended current collector foils 12 and 13, etc.

[0019] As shown in Figure 4(b), in welding process S2, the extended current collector foils 12 and the extended current collector foils 13 are welded together by the welding device 70. In this embodiment 1, the welding device 70 is configured separately from the pressing jig 50. In this embodiment 1, the welding device 70 is an ultrasonic welding machine and has a horn 71 which is an ultrasonic transducer and an anvil 72 which is a base positioned opposite the horn 71. As shown in Figure 4(b), the extended current collector foils 12, which have been deformed into a shape conforming to the target shape, are placed on the anvil 72, and as shown in Figure 5(a), the horn 71 is lowered toward the extended current collector foils 12 and brought into contact with them, thereby applying ultrasonic vibrations from the horn 71 and welding the extended current collector foils 12 together.

[0020] In this embodiment 1, as shown in Figure 5(a), welding of the extended current collector foil 12 by the welding device 70 is performed while the extended current collector foil 12 is pressed by the pressing jig 50. However, if the extended current collector foil 12 maintains its shape (formed) to the target shape even after releasing the pressure from the pressing jig 50, welding by the welding device 70 may be performed after releasing the pressure from the pressing jig 50. After welding, the uneven ends 123 of the extended current collector foil 12, caused by the pressure from the pressing jig 50, are trimmed using a cutter (not shown) as shown in Figure 5(b). Although not shown, the extended current collector foils 13 are also welded together and their ends trimmed in the same manner as the extended current collector foils 12. Then, as shown in Figures 6(a) and 6(b), the current collector tabs 21 are welded to the extended current collector foil 12 using the welding device 70. As shown in Figure 6(b), the current collector tabs 22 are similarly welded to the extended current collector foil 13.

[0021] Next, after the welding process S2 is completed, the sealing process S3 is performed. In the sealing process S3, first, as shown in Figures 7(a) and 7(b), the laminate 10 is covered with the outer casing 20. As shown in Figure 7(b), the outer casing 20 consists of an upper outer casing 20a and a lower outer casing 20b. The upper outer casing 20a and the lower outer casing 20b each have recesses 25 and 26 formed at positions facing the laminate body 11. As shown in Figure 7(b), by aligning the upper outer casing 20a and the lower outer casing 20b as indicated by the arrow P, a space slightly larger than the outer shape of the laminate body 11 is formed by the recesses 25 and 26, and the laminate body 11 is housed in this space. In this embodiment 1, the upper outer casing 20a and the lower outer casing 20b have symmetrical shapes in the thickness direction Z. Alternatively, one of the upper or lower outer casing 20a or 20b may have a recess slightly larger than the outer shape of the laminate body 11, while the other is flat. The material of the outer casing 20 is not limited, but in this embodiment 1, an aluminum laminate is used, which is made by forming resin layers on both sides of a thin aluminum film.

[0022] In the sealing process S3, as shown in Figure 8(a), an adhesive layer 27 is provided in the area where the current collector tab 21 and the outer casing 20 overlap. The material of the adhesive layer 27 is not limited; it should have adhesive strength to both the resin layer (not shown) provided on the surface of the outer casing 20 and the metal current collector tabs 21 and 22. Then, at the outer edge 29 of the outer casing 20 shown in Figure 7(a), the area where the current collector tab 21 is present is joined to the upper outer casing 20a and the lower outer casing 20b via the adhesive layer 27, and the remaining area is heat-welded between the upper outer casing 20a and the lower outer casing 20b, thereby sealing the outer periphery of the laminate 10. As a result, the laminate 10 is enclosed within the outer casing 20. Note that immediately after the sealing process S3, as shown in Figure 8(b), a gap R is formed between the outer casing 20 and the extended current collector foil 12 and the outer casing 20.

[0023] Furthermore, as shown in Figure 7(a), on one of the sides of the laminate 10 where the current-collecting tabs 21 and 22 are not provided, the outer casing 20 extends outward to form a gas pocket 28. In the gas pocket 28, the upper outer casing 20a and the lower outer casing 20b are not joined to each other in portions other than the outer edge 29, and the gas pocket 28 is bag-shaped.

[0024] After the sealing process S3 is completed, a hole 28a as shown in Figure 7(a) is made in the gas pocket 28 and electrolyte is injected into the outer casing 20 to perform the initial charging process S4. The initial charging process S4 is performed by energizing the laminate 10 for a predetermined time via the current collecting tabs 21 and 22, although this is not shown in the figure. During the initial charging process S4, gas is generated inside the outer casing 20 due to the charging. The generated gas is stored in the gas pocket 28 inside the outer casing 20. In addition, a pre-doping process may be performed before the initial charging process S4 in order to pre-dope lithium ions into the negative electrode 11b. Furthermore, an aging process may be performed as desired after the completion of the initial charging process S4.

[0025] Then, after the initial charging process S4 is completed, or after the aging process is completed if an aging process has been performed, a degassing process S5 is carried out. In the degassing process S5, degassing is performed by vacuuming from the inside of the outer casing 20 through a perforation 28a provided in the gas pocket 28 using a suction device (not shown). As a result, the gas inside the outer casing 20 is removed to the outside, and as shown in Figure 8(c), the gap R between the outer casing 20 and the extended current collector foil 12 disappears, and the outer casing 20 is pressed against the extended current collector foil 12.

[0026] After the degassing process S5 is completed, the resealing process S6 is performed. In the resealing process S6, at the joining position A shown in Figure 7(a), the upper outer casing 20a and the lower outer casing 20b of the outer casing 20 are heat-sealed using a welding device (not shown). As a result, the gas pocket 28 and the space containing the laminate body 11 are no longer in communication inside the outer casing 20, and the space containing the laminate body 11 is completely sealed.

[0027] Next, after the resealing process S6 is completed, the excision process S6 is performed. In the excision process S6, the outer casing 20 is cut at the planned cutting position B shown in Figure 7(a) using a cutter (not shown). This excises the gas pocket 28. After that, a seal condition confirmation test is performed, and those that are confirmed to have a good seal condition are completed as the energy storage device 100 shown in Figure 1(a).

[0028] Furthermore, the manufacturing apparatus 200 for manufacturing the energy storage device 100 in this embodiment 1 includes a pressing jig 50, a support base 60, and a welding apparatus 70, as shown in Figures 4(a) and (b), and Figures 5(a) and (b), with the pressing jig 50 positioned between the support base 60 and the welding apparatus 70. As described above, the support base 60 supports a laminate 10 which comprises a laminate body 11 formed by laminating sheet-shaped positive electrodes 11a and negative electrodes 11b together with a separator 11c, and a plurality of extended current collector foils 12 and 13 that extend outward from the laminate body 11 and are stacked in the lamination direction. The welding apparatus 70 welds multiple overlapping extended current collector foils 12 and 13 together at the planned welding positions 121 and 131. The pressing jig 50 is provided between the support base 60 and the welding device 70, and presses the areas 122 and 132 of the extended current collector foil 12 and 13 that are closer to the laminate body 11 than the planned welding positions 121 and 131, thereby deforming them into the target shape. The manufacturing apparatus 200 can be used to manufacture the energy storage device 100 shown in Figure 1(a) by performing the manufacturing method 1 shown in Figure 2.

[0029] In this embodiment 1, the welding device 70 is an ultrasonic welding machine as described above, but it is not limited to this and may be a spot welding machine or a laser welding machine. Also, the pressing jig 50 is made up of two parts, a base plate 51 and a resin plate 52, but instead it may be made up of a single part in which the base plate 51 and the resin plate 52 are integrated. Furthermore, in this embodiment 1, the welding device 70 and the pressing jig 50 are separate, but instead one of the pair of pressing jigs 50 may be integrated with the horn 71 of the welding device 70, and the other of the pair of pressing jigs 50 may be integrated with the anvil 72 of the welding device 70, thereby integrating the welding device 70 and the pressing jig 50 as a single unit.

[0030] Next, the effects and advantages of the manufacturing method 1 for the energy storage device 100 of this embodiment 1 will be described in detail. According to the manufacturing method 1 of the energy storage device 100 of this embodiment 1, when welding multiple extended current collector foils 12 and 13 together, the pressing jig 50 is pressed against the extended current collector foils 12 and 13 between the planned welding positions 121 and 131 and the laminate body 11, thereby deforming the extended current collector foils 12 and 13 into the target shape. Therefore, when the extended current collector foils 12 and 13 are pressed with the pressing jig 50, the extended current collector foils 12 and 13 are not welded, so the pressing of the pressing jig 50 can deform the extended current collector foils 12 and 13 into a smooth shape that conforms to the target shape without crushing them. As a result, excessive stress on the extended current collector foils 12 and 13 is suppressed, and the fracture of the extended current collector foils 12 and 13 is prevented. Furthermore, when covering the laminate 10 with the outer casing 20 or when venting gas from inside the outer casing 20, the extended current collector foils 12 and 13 are already molded to the target shape. Therefore, even if the outer casing 20 presses against the extended current collector foils 12 and 13, excessive stress on the extended current collector foils 12 and 13 is suppressed, and the fracture of the extended current collector foils 12 and 13 is prevented.

[0031] Furthermore, in this embodiment 1, the target shape is a shape that follows the inner surface 23 of the outer casing 20 of the completed energy storage device 100. As a result, deformation of the extended current collector foils 12 and 13 due to the pressure of the outer casing 20 is less likely to occur when covering the laminate 10 with the outer casing 20 or when venting gas from inside the outer casing 20. This further suppresses excessive stress on the extended current collector foils 12 and 13, and further prevents breakage of the extended current collector foils 12 and 13.

[0032] Furthermore, in this embodiment 1, in welding step S2, the welding of the extended current collector foils 12 and 13 is performed with the pressing jig 50 pressed against them. This ensures that the extended current collector foils 12 and 13 are reliably maintained in the target shape by the pressing jig 50 while being welded. As a result, misalignment of the extended current collector foils 12 and 13 during welding is prevented, and the extended current collector foils 12 and 13 can maintain the target shape even after welding.

[0033] Furthermore, in this embodiment 1, welding is performed in welding step S2 using a welding device 70 that is provided separately from the pressing jig 50. This suppresses the transmission of vibrations generated during welding in the welding device 70 to the pressing jig 50, and allows the pressing jig 50 to reliably maintain the extended current collector foils 12 and 13 in the target shape. In addition, it becomes easier to adjust the pressing position by the pressing jig 50 and the welding position by the welding device 70 individually, making it easy to use even with energy storage devices 100 of different shapes.

[0034] Furthermore, in this embodiment 1, the tip 52a of the pressing jig 50 has a curved shape that follows the inner side surface 23 of the outer casing 20 of the completed energy storage device 100, and in the welding process S2, the tip 52a of the pressing jig 50 is pressed against the extended current collector foils 12 and 13 to deform them into the target shape. This prevents the extended current collector foils 12 and 13 from being damaged by the tip 52a of the pressing jig 50. In addition, in this embodiment 1, since the tip 52a of the pressing jig 50 is formed as part of the resin plate 52 made of resin, the hardness of the tip 52a is lower compared to when the tip 52a is made of metal. This also prevents the extended current collector foils 12 and 13 from being damaged by the tip 52a of the pressing jig 50.

[0035] Furthermore, in the manufacturing apparatus 200 for the energy storage device 100 of this embodiment 1, by having the above configuration, the pressing jig 50 can press the areas 122 and 132 of the extended current collector foils 12 and 13 that are closer to the laminate body 11 than the planned welding positions 121 and 131 to deform them into the target shape, or simultaneously with such deformation, the welding apparatus 70 can weld the extended current collector foils 12 and 13 at the planned welding positions 121 and 131. As a result, the pressing jig 50 can deform the extended current collector foils 12 and 13 into a smooth shape that conforms to the target shape without crushing them, thereby suppressing excessive stress on the extended current collector foils 12 and 13 and preventing them from breaking.

[0036] As described above, according to the above embodiment, a method for manufacturing an energy storage device 100 and a manufacturing apparatus 200 therefor can be provided that prevents damage to the extended current collector foils 12 and 13.

[0037] The present invention is not limited to the above embodiments and variations, and can be applied to various embodiments without departing from its spirit. [Explanation of symbols]

[0038] 1: Method for manufacturing an energy storage device, 100: Energy storage device, 200: Equipment for manufacturing an energy storage device, 10: Laminate, 11a: Positive electrode, 11b: Negative electrode, 11c: Separator, 11: Laminate body, 12-13: Extended current collector foil, 20: Outer casing, 23: Inner side of outer casing, 21-22: Current collector tab, 50: Pressing jig, 60: Support base, 70: Welding equipment, 121-131: Planned welding positions

Claims

1. In a method for manufacturing an energy storage device, the laminate comprises a laminate body formed by laminating sheet-shaped positive and negative electrodes together with a separator, and a plurality of extended current collector foils extending outward from the laminate body and overlapping in the lamination direction, and the laminate is enclosed in a film-like outer casing. A welding process in which the tip of a pressing jig is pressed into the area between the planned welding position and the laminate body of the overlapping extended current collector foils to deform the extended current collector foils into the target shape, and the extended current collector foils are welded together at the planned welding position, A sealing step in which the laminate is covered with the outer casing and the outer periphery of the laminate is sealed by the outer casing, A gas venting process is performed to release gas from the inside of the sealed exterior body, Includes, The above target shape is a shape that follows the inner surface of the outer casing of the completed energy storage device. The tip of the above pressing jig has a curved shape that conforms to the inner surface of the outer casing of the completed energy storage device. A method for manufacturing an energy storage device, wherein the degassing step involves removing the gas inside the outer casing to the outside of the outer casing by the degassing, thereby pressing the outer casing against the extended current collector foil that has been deformed into the target shape.

2. A method for manufacturing an energy storage device according to claim 1, wherein the welding is performed with the pressing jig pressed against the extended current collector foil during the welding process.

3. A method for manufacturing an energy storage device according to claim 1 or 2, wherein the welding process is performed using a welding device provided separately from the pressing jig.

4. An apparatus for manufacturing an energy storage device comprising a laminate body comprising a laminate body formed by laminating sheet-shaped positive and negative electrodes together with a separator, and a plurality of extended current collector foils extending outward from the laminate body and overlapping in the lamination direction, the laminate body being sealed in a film-like outer casing, A support base for supporting the above laminated structure, A welding apparatus for welding the overlapping extended current collector foils to each other at the planned welding position, A pressing jig is provided between the support base and the welding apparatus, and before or simultaneously with welding, presses the area of ​​the extended current collector foil closer to the laminate body than the planned welding position with its tip to deform it into a target shape, A suction device that covers the laminate and seals the outer periphery of the laminate, and vents gas from the inside of the outer casing, Equipped with, The above target shape is a shape that follows the inner surface of the outer casing of the completed energy storage device. The tip of the above pressing jig has a curved shape that conforms to the inner surface of the outer casing of the completed energy storage device. The welding apparatus, with the extended current collector foil deformed into the target shape, welds the overlapping extended current collector foils together at the planned welding position. The above-described suction device is a manufacturing apparatus for an energy storage device, which presses the outer casing against the extended current collector foil that has been deformed into the above-described target shape by removing the gas inside the outer casing to the outside of the outer casing through the above-described degassing.

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