JP2019040792A - Method for manufacturing power storage module and power storage module - Google Patents

Abstract

To provide a method of manufacturing an electricity storage module and an electricity storage module capable of improving the yield of the sealing material while ensuring the airtightness of the sealing material. A method of manufacturing an electricity storage module according to one aspect includes a step of obtaining a plurality of non-annular divided pieces 60 for forming an annular first resin portion 52 from a sheet material F, and a step of seeing from a stacking direction D1. A plurality of divided pieces on the edge 34a of the electrode plate 34 so that the end of each divided piece 60 in the ring direction of the first resin portion 52 overlaps with the portion other than the end of the other divided pieces 60 in the ring direction. A step of arranging 60, a step of forming the first resin portion 52 by welding a plurality of divided pieces 60 to the edge portion 34a of the electrode plate 34, and a step of laminating the bipolar electrodes 32 to obtain a laminated body 30. And, including. [Selection diagram] Fig. 5

Description

  One aspect of the present invention relates to a method for manufacturing a power storage module and a power storage module.

  As a conventional power storage device, a bipolar battery including a bipolar electrode in which a positive electrode is formed on one surface of an electrode plate and a negative electrode is formed on the other surface is known (see Patent Document 1). The bipolar battery is provided with a laminate formed by laminating a plurality of bipolar electrodes via a separator. A sealing body (sealing material) that seals between the bipolar electrodes adjacent to each other in the stacking direction is provided on the side surface of the stacked body, and an electrolytic solution is accommodated in an internal space formed between the bipolar electrodes.

JP 2011-204386 A

  Here, the sealing material provided between the bipolar electrodes is formed in a rectangular ring shape in accordance with the shape of the edge of the bipolar electrode. Such a sealing material can be obtained, for example, by punching out a long sheet material fed from a raw fabric roll. However, when a sealing material is obtained by such a punching process, an inner portion (rectangular cut end) of the sealing material cannot be used as the sealing material, and thus becomes a disposal target. For this reason, there exists a problem that the discard rate of a sheet material becomes high and a yield falls.

  An object of one aspect of the present invention is to provide a method for manufacturing an electricity storage module and an electricity storage module that can improve the yield of the sealant while ensuring the airtightness of the sealant.

  A method of manufacturing a power storage module according to one aspect of the present invention includes stacking a plurality of bipolar electrodes each including an electrode plate, a positive electrode provided on one surface of the electrode plate, and a negative electrode provided on the other surface of the electrode plate. A plurality of non-annular divided pieces for forming a sealing material from a sheet material, the method comprising: manufacturing a power storage module having a laminated body and an annular sealing material welded to an edge of each electrode plate And the edge of the electrode plate so that the end of each divided piece in the ring direction of the sealing material overlaps with a portion other than the end in the ring direction of the other divided piece when viewed from the stacking direction of the laminate Including a step of disposing a plurality of divided pieces, a step of forming a sealing material by welding the plurality of divided pieces to an edge of the electrode plate, and a step of obtaining a laminate by laminating bipolar electrodes. .

  When the annular sealing material is directly punched from the sheet material, the inner portion of the sealing material is generated as a secondary object to be discarded, resulting in a high sheet material disposal rate. On the other hand, since the sealing material is formed by a plurality of non-annular divided pieces in the method for manufacturing the electricity storage module, an inner portion of the sealing material to be discarded does not occur when the annular sealing material is directly punched from the sheet material. . Moreover, in the said manufacturing method, it arrange | positions so that the edge part in the ring direction of each division piece may overlap with parts other than the edge part in the ring direction of another division piece seeing from the lamination direction. Thereby, the clearance gap or the joint line between adjacent division pieces is appropriately filled at the time of welding, and the airtightness of a sealing material is ensured. Therefore, according to the manufacturing method, it is possible to improve the yield of the sealing material while ensuring the hermeticity of the sealing material.

  The sealing material includes a plurality of first divided pieces arranged on the edge of the electrode plate and a plurality of second divided pieces arranged on the plurality of first divided pieces, and the step of arranging the divided pieces includes: The step of arranging the plurality of first divided pieces on the edge of the electrode plate so that the plurality of first divided pieces do not overlap each other when viewed from the stacking direction, and the plurality of second divided pieces overlap each other when viewed from the stacking direction. And a plurality of second divided pieces on the plurality of first divided pieces so that the region between the first divided pieces adjacent to each other as viewed from the stacking direction does not overlap with the area between the adjacent second divided pieces. And a placing step. According to the above configuration, the sealing material can be appropriately formed by the two-layer structure of the first layer formed by the plurality of first divided pieces and the second layer formed by the plurality of second divided pieces. . Specifically, since welding is performed in a state where the region between the first divided pieces in the first layer and the region between the second divided pieces in the second layer are arranged at positions shifted from the stacking direction, The gaps or joints between the adjacent first divided pieces and the gaps or joints between the second divided pieces are appropriately filled, and the sealing material is secured.

  The thickness of the edge portions on both sides of the sheet material in the width direction intersecting the longitudinal direction of the sheet material is approximately half the thickness of the central portion between the edge portions on both sides of the sheet material, and a step of obtaining divided pieces 2, two edge portions for connecting to the other divided pieces are formed by the edge portions on both sides of the sheet material, and the main body portion between the two edge portions of the divided piece is formed by the central portion of the sheet material. In the step of obtaining the divided pieces and arranging the divided pieces, a plurality of divided pieces are arranged on the edge of the electrode plate so that the edges of the adjacent divided pieces overlap each other when viewed from the stacking direction. May be. According to the above configuration, the thickness of the two edge portions for connecting to the other divided pieces by punching or the like from the sheet material in which the thickness of the edge portions on both sides in the width direction is substantially half the thickness of the central portion. Therefore, it is possible to easily obtain a split piece that is approximately half the thickness of the main body. Further, since the divided pieces are connected by overlapping the edge portions of the adjacent divided pieces, the thickness of the portion where the edge portions overlap is substantially the same as the thickness of the main body portion of the divided piece. In addition, since the edges of the adjacent divided pieces are connected to each other, it is possible to arrange a plurality of divided pieces so that the gap between the adjacent divided pieces is reduced. That is, according to the said structure, a some division | segmentation piece can be arrange | positioned so that thickness may become fixed and the clearance gap between division pieces may become small. As a result, it is possible to suppress the occurrence of a level difference in the sealing material that may occur during welding (a level difference caused by a gap between the divided pieces) and improve the dimensional accuracy of the power storage module.

  The sealing material has a rectangular ring shape, and the plurality of divided pieces include divided pieces formed in an L shape. In the step of arranging the divided pieces, the divided pieces formed in the L shape are used as corner portions of the sealing material. You may arrange | position in the position corresponding to. According to the above configuration, it is possible to easily align the divided pieces, and it is possible to suppress the positional deviation of the divided pieces.

  An electricity storage module according to one aspect of the present invention is a laminate in which a plurality of bipolar electrodes each including an electrode plate, a positive electrode provided on one surface of the electrode plate, and a negative electrode provided on the other surface of the electrode plate are laminated. And an annular sealing material welded to the edge of each electrode plate, the sealing material is formed from a plurality of non-annular divided pieces, and the sealing material is seen from the stacking direction of the laminate. An end portion of each divided piece in the ring direction overlaps with a portion other than an end portion in the ring direction of the other divided pieces.

  In the power storage module, since the sealing material is formed by a plurality of non-annular divided pieces, an inner portion of the sealing material to be discarded does not occur when the annular sealing material is directly punched from the sheet material. Moreover, in the said electrical storage module, seeing from the lamination direction, the edge part of each division | segmentation piece in the ring direction of a sealing material is arrange | positioned so that it may overlap with parts other than the edge part in the ring direction of another division | segmentation piece. For this reason, the gaps or joints between the adjacent divided pieces are appropriately filled by welding, and the airtightness of the sealing material is ensured. Therefore, according to the power storage module, it is possible to improve the yield of the sealing material while ensuring the airtightness of the sealing material.

  According to one aspect of the present invention, it is possible to provide a method of manufacturing a power storage module and a power storage module that can improve the yield of the sealing material while ensuring the airtightness of the sealing material.

It is a schematic sectional drawing which shows one Embodiment of an electrical storage apparatus provided with an electrical storage module. It is a schematic sectional drawing which shows the electrical storage module of FIG. It is a figure for demonstrating the manufacturing method of an electrical storage module. It is a figure for demonstrating the manufacturing method of an electrical storage module. It is a figure for demonstrating the manufacturing method of an electrical storage module. It is a figure for demonstrating the manufacturing method of the electrical storage module which concerns on a modification. It is a figure for demonstrating the manufacturing method of the electrical storage module which concerns on a modification.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings. In the description of the drawings, the same reference numerals are used for the same or equivalent elements, and redundant descriptions are omitted. In the drawing, an XYZ orthogonal coordinate system is shown.

[Configuration of power storage device]
FIG. 1 is a schematic cross-sectional view illustrating an embodiment of a power storage device including a power storage module. The power storage device 10 shown in the figure is used as a battery for various vehicles such as forklifts, hybrid vehicles, and electric vehicles. The power storage device 10 includes a plurality (three in the present embodiment) of power storage modules 12, but may include a single power storage module 12. The power storage module 12 is, for example, a bipolar battery. The power storage module 12 is a secondary battery such as a nickel hydride secondary battery or a lithium ion secondary battery, but may be an electric double layer capacitor. In the following description, a nickel metal hydride secondary battery is illustrated.

  The plurality of power storage modules 12 can be stacked via a conductive plate 14 such as a metal plate. As viewed from the stacking direction D1, the power storage module 12 and the conductive plate 14 have, for example, a rectangular shape. Details of each power storage module 12 will be described later. The conductive plates 14 are also arranged outside the power storage modules 12 positioned at both ends in the stacking direction D1 (Z direction) of the power storage modules 12, respectively. The conductive plate 14 is electrically connected to the adjacent power storage module 12. Thereby, the some electrical storage module 12 is connected in series in the lamination direction D1. In the stacking direction D1, a positive electrode terminal 24 is connected to the conductive plate 14 located at one end, and a negative electrode terminal 26 is connected to the conductive plate 14 located at the other end. The positive terminal 24 may be integrated with the conductive plate 14 to be connected. The negative electrode terminal 26 may be integrated with the conductive plate 14 to be connected. The positive electrode terminal 24 and the negative electrode terminal 26 extend in a direction (X direction) intersecting the stacking direction D1. The positive and negative terminals 24 and 26 can charge and discharge the power storage device 10.

  The conductive plate 14 can also function as a heat radiating plate for releasing heat generated in the power storage module 12. When a refrigerant such as air passes through the plurality of gaps 14a provided inside the conductive plate 14, heat from the power storage module 12 can be efficiently released to the outside. Each gap 14a extends, for example, in a direction (Y direction) intersecting the stacking direction D1. As viewed from the stacking direction D1, the conductive plate 14 is smaller than the power storage module 12, but may be the same as or larger than the power storage module 12.

  The power storage device 10 may include a restraining member 16 that restrains the alternately stacked power storage modules 12 and conductive plates 14 in the stacking direction D1. The restraining member 16 includes a pair of restraining plates 16A and 16B and a connecting member (bolt 18 and nut 20) for joining the restraining plates 16A and 16B to each other. An insulating film 22 such as a resin film is disposed between the restraining plates 16A and 16B and the conductive plate. Each restraint plate 16A, 16B is comprised, for example with metals, such as iron. When viewed from the stacking direction D1, each of the restraining plates 16A and 16B and the insulating film 22 has, for example, a rectangular shape. The insulating film 22 is larger than the conductive plate 14, and the restraining plates 16 </ b> A and 16 </ b> B are larger than the power storage module 12. As viewed from the stacking direction D1, an insertion hole H1 through which the shaft portion of the bolt 18 is inserted is provided at a position on the outer side of the power storage module 12 at the edge portion of the restraint plate 16A. Similarly, an insertion hole H2 through which the shaft portion of the bolt 18 is inserted is provided at a position on the outer side of the power storage module 12 at the edge portion of the restraining plate 16B when viewed from the stacking direction D1. When each restraint plate 16A, 16B has a rectangular shape when viewed from the stacking direction D1, the insertion hole H1 and the insertion hole H2 are located at the corners of the restraint plates 16A, 16B.

  One constraining plate 16A is abutted against the conductive plate 14 connected to the negative terminal 26 via the insulating film 22, and the other constraining plate 16B has the insulating film 22 applied to the conductive plate 14 connected to the positive terminal 24. Has been hit through. For example, the bolt 18 is passed through the insertion hole H1 from one restraint plate 16A side to the other restraint plate 16B side, and a nut 20 is screwed to the tip of the bolt 18 protruding from the other restraint plate 16B. Yes. Thereby, the insulating film 22, the conductive plate 14, and the power storage module 12 are sandwiched and unitized, and a restraining load is applied in the stacking direction D1.

  2 is a schematic cross-sectional view showing a power storage module constituting the power storage device of FIG. The power storage module 12 shown in the figure includes a stacked body 30 in which a plurality of bipolar electrodes (electrodes) 32 are stacked. The laminated body 30 has, for example, a rectangular shape when viewed from the lamination direction D1 of the bipolar electrode 32. A separator 40 may be disposed between the adjacent bipolar electrodes 32. The bipolar electrode 32 includes an electrode plate 34, a positive electrode 36 provided on one surface of the electrode plate 34, and a negative electrode 38 provided on the other surface of the electrode plate 34. In the stacked body 30, the positive electrode 36 of one bipolar electrode 32 faces the negative electrode 38 of one bipolar electrode 32 adjacent in the stacking direction D 1 across the separator 40, and the negative electrode 38 of one bipolar electrode 32 is connected to the separator 40. Is opposed to the positive electrode 36 of the other bipolar electrode 32 adjacent in the stacking direction D1. In the stacking direction D1, an electrode plate 34 (negative electrode termination electrode) having a negative electrode 38 disposed on the inner surface is disposed at one end of the stacked body 30, and a positive electrode 36 is disposed on the inner surface at the other end of the stacked body 30. The disposed electrode plate 34 (positive terminal electrode) is disposed. The negative electrode 38 of the negative electrode-side termination electrode faces the positive electrode 36 of the uppermost bipolar electrode 32 with the separator 40 interposed therebetween. The positive electrode 36 of the positive terminal electrode is opposed to the negative electrode 38 of the lowermost bipolar electrode 32 with the separator 40 interposed therebetween. The electrode plates 34 of these termination electrodes are connected to the adjacent conductive plates 14 (see FIG. 1).

  The power storage module 12 includes a frame 50 that holds the edge 34a of the electrode plate 34 on the side surface 30a of the stacked body 30 extending in the stacking direction D1. The frame body 50 is provided around the stacked body 30 when viewed from the stacking direction D1. That is, the frame body 50 is configured to surround the side surface 30 a of the stacked body 30. The frame 50 includes a first resin portion 52 (seal material) that holds the edge portion 34a of the electrode plate 34, and a second resin portion 54 that is provided around the first resin portion 52 when viewed from the stacking direction D1. obtain.

  The first resin portion 52 constituting the inner wall of the frame 50 is provided from one surface (surface on which the positive electrode 36 is formed) of the electrode plate 34 of each bipolar electrode 32 to the end surface of the electrode plate 34 at the edge portion 34a. . As viewed from the stacking direction D1, each first resin portion 52 is provided over the entire circumference of the edge portion 34a of the electrode plate 34 of each bipolar electrode 32. The first resin portion 52 is formed in a rectangular ring shape so as to surround the electrode plate 34 of the bipolar electrode 32 when viewed from the stacking direction D1. The first resin portion 52 is formed of a plurality of non-annular divided pieces 60 (see FIGS. 3 to 5). Although mentioned later in detail, the 1st resin part 52 is formed as follows. That is, the plurality of divided pieces 60 are arranged on the edge portion 34a of the electrode plate 34 so that the end portions of the respective divided pieces 60 overlap with portions other than the end portions of the other divided pieces 60 as viewed from the stacking direction D1. ing. Then, with the plurality of divided pieces 60 arranged in this way, the plurality of divided pieces 60 are welded to each other and welded to the edge 34a of the electrode plate 34, whereby the edge of each electrode plate 34 is obtained. A first resin portion 52 is formed at 34a. As described above, the first resin portion 52 is formed on the edge portion 34 a of each electrode plate 34, whereby the edge portion 34 a of the electrode plate 34 of each bipolar electrode 32 is embedded and held in the first resin portion 52. ing. Similarly to the edge portion 34 a of the electrode plate 34 of each bipolar electrode 32, the edge portions 34 a of the electrode plates 34 disposed at both ends of the laminated body 30 are also held in a state of being buried in the first resin portion 52. Thus, an internal space V that is airtightly partitioned by the electrode plates 34 and 34 and the first resin portion 52 is formed between the electrode plates 34 and 34 adjacent in the stacking direction D1. In the internal space V, for example, an electrolytic solution (not shown) made of an alkaline solution such as an aqueous potassium hydroxide solution is accommodated.

  The 2nd resin part 54 which comprises the outer wall of the frame 50 is a cylindrical part extended about the lamination direction D1 as an axial direction. The second resin portion 54 extends over the entire length of the stacked body 30 in the stacking direction D1. The second resin portion 54 covers the outer surface of the first resin portion 52 extending in the stacking direction D1. The second resin portion 54 is welded to the first resin portion 52 on the inner side when viewed from the stacking direction D1. The second resin portion 54 is formed in a rectangular cylindrical shape by injection molding using, for example, an insulating resin. Examples of the resin material constituting the frame 50 include polypropylene (PP), polyphenylene sulfide (PPS), and modified polyphenylene ether (modified PPE).

  The electrode plate 34 is a rectangular metal foil made of nickel, for example. The edge portion 34 a of the electrode plate 34 is an uncoated region where the positive electrode active material and the negative electrode active material are not coated, and the uncoated region is buried in the first resin portion 52 constituting the inner wall of the frame body 50. It is an area to be held. An example of the positive electrode active material constituting the positive electrode 36 is nickel hydroxide. Examples of the negative electrode active material constituting the negative electrode 38 include a hydrogen storage alloy. The formation region of the negative electrode 38 on the other surface of the electrode plate 34 is slightly larger than the formation region of the positive electrode 36 on one surface of the electrode plate 34.

  The separator 40 is formed in a sheet shape, for example. Examples of the material forming the separator 40 include a porous film made of a polyolefin resin such as polyethylene (PE) and polypropylene (PP), and a woven fabric or a nonwoven fabric made of polypropylene. The separator 40 may be reinforced with a vinylidene fluoride resin compound or the like. The separator 40 is not limited to a sheet shape, and may be a bag shape.

[Method for manufacturing power storage module]
With reference to FIGS. 3-5, the manufacturing method (mainly the formation method of the 1st resin part 52) of the electrical storage module 12 is demonstrated.

(Divided piece acquisition process)
As shown in FIG. 3A, first, a plurality of non-annular divided pieces 60 are obtained from the long sheet material F. The sheet material F is a film sheet formed of a resin material that constitutes the frame body 50 as described above, and is fed out of, for example, a raw roll. The divided piece 60 is obtained by punching the sheet material F by punching, for example. Although the punching method is not particularly limited, the divided pieces 60 can be obtained by, for example, pressing with a flat plate punching machine, cutting with a rotary cutter, or the like. In this embodiment, the division | segmentation piece 60 formed in L shape is acquired. Further, by using two different types of molds, two types of L-shaped divided pieces 61 (61A, 61B) and 62 (62A, 62B) having different sizes are acquired ((B) in FIG. 4). And FIG. 5). The length of the long side member of the split piece 61 (the member having the longer side of the two rectangular portions extending in an L shape) is set to be longer than the length of the long side member of the split piece 62. Specifically, by alternately arranging the divided pieces 61 and the divided pieces 62, the shape of the divided pieces 61 and the divided pieces 62 and the rectangular pieces along the edge 34a of the electrode plate 34 are formed. The size is set. It should be noted that the sheet material F used when punching the split piece 61 and the sheet material F used when punching the split piece 62 may be the same. For example, the size of each of the split pieces 61 and 62 may be the same. Sheet materials having different sizes and different sizes may be used.

  FIG. 3B shows an example in which a rectangular annular resin piece 600 corresponding to the first resin portion 52 (a resin piece not divided into a plurality of non-annular divided pieces 60) is punched from the sheet material F as a comparative example. Is shown. In this comparative example, the inner part 601 of the resin piece 600 is generated as a secondary object as a disposal target. Further, since the inner portion 601 has a relatively large area, the discard rate of the sheet material F (ratio of the area of the portion that was not used to form the first resin portion 52 with respect to the entire area of the used sheet material F). Becomes higher. On the other hand, as shown in FIG. 3A, by using the non-annular divided piece 60 as an object to be punched, it is possible to prevent generation of useless parts such as the inner part 601 in the comparative example, The discard rate of the material F can be reduced.

(Split piece placement process)
Subsequently, as viewed from the stacking direction D1, the first resin portion 52 is formed by a plurality of first divided pieces 61A and 62A in the ring direction (the direction along the edge 34a and the circumferential direction around the Z direction). It has a two-layer structure of the first layer and the second layer formed by the plurality of second divided pieces 61B and 62B in the ring direction, and the end portion of the divided piece 60 in the first layer (the joining portion of 61A and 62A) ) Are arranged so as to overlap other than the end portions (joined portions of 61B and 62B) of the divided pieces 60 in the second layer. For this reason, in the present embodiment, the thickness of the sheet material F is half of the thickness of the sheet material used when the resin piece 600 corresponding to the first resin portion 52 is punched out. Thereby, when forming the 1st resin part 52 by the above two-layer structures, the thickness of the 1st resin part 52 can be made into an appropriate magnitude | size.

  First, as shown in FIG. 4A, an electrode plate 34 provided with a positive electrode 36 on one side is prepared. Subsequently, as shown in FIG. 4B, the first divided pieces 61A and 62A are arranged along the edge 34a of the electrode plate 34 (first divided piece arrangement step). Specifically, the two first divided pieces 61A and the two first divided pieces 62A are arranged in a rectangular frame shape along the edge 34a of the electrode plate 34 when viewed from the stacking direction D1 (Z direction). The The first divided pieces 61 </ b> A and 62 </ b> A each formed in an L shape are disposed at positions corresponding to the corners of the first resin portion 52. The first divided pieces 61A and the first divided pieces 62A are alternately arranged along the circumferential direction (the direction along the edge 34a of the electrode plate 34).

  The plurality of first divided pieces 61A and 62A are arranged so as not to overlap each other when viewed in the stacking direction D1. For example, the end 61Aa on the long side of the first divided piece 61A is in contact with the end 62Ab on the short side of the first divided piece 62A adjacent to the long side of the first divided piece 61A, or As shown in FIG. 4B, they are slightly separated. Similarly, the end 61Ab on the short side of the first divided piece 61A and the end 62Aa on the long side of the first divided piece 62A adjacent to the short side of the first divided piece 61A come into contact with each other. Alternatively, they are slightly separated as shown in FIG. In this way, the two first divided pieces 61A and the two first divided pieces 62A are arranged point-symmetrically with respect to the center A of the electrode plate 34 when viewed from the Z direction.

  Subsequently, as shown in FIG. 5, a plurality of second divided pieces 61B and 62B are arranged on the plurality of first divided pieces 61A and 62A (second divided piece arrangement step). Specifically, the two second divided pieces 61B and the two second divided pieces 62B are arranged so as not to overlap each other when viewed from the stacking direction D1. The two second divided pieces 61B and the two second divided pieces 62B are the second divided pieces adjacent to the region (gap or joint) between the first divided pieces 61A and 62A adjacent to each other when viewed in the stacking direction D1. It arrange | positions so that the area | region (gap or a joint) between 61B and 62B may not overlap.

  As shown in FIG. 4B and FIG. 5, in the present embodiment, the second divided pieces 61B and 62B are arranged around the X direction as viewed from the stacking direction D1. (Or around the Y direction) is equal to the arrangement in a state of being inverted 180 degrees. Thereby, arrangement | positioning of several 2nd division | segmentation pieces 61B and 62B as mentioned above is implement | achieved. That is, the region between the first divided pieces 61A and 62A (here, the gap between the end portion 61Aa and the end portion 62Ab, or the gap between the end portion 61Ab and the end portion 62Aa), and the second divided piece. The region between 61B and 62B (here, the gap between the end portion 61Ba and the end portion 62Bb, or the gap between the end portion 61Bb and the end portion 62Ba) does not overlap each other when viewed from the stacking direction D1. In addition, a plurality of second divided pieces 61B and 62B are arranged. In other words, when viewed from the stacking direction D1, the end portions 61Aa, 61Ab, 62Aa, 62Ab of the first divided pieces 61A, 62A in the ring direction are the end portions 61Ba, 62Ba, 62Ab of the second divided pieces 61B, 62B in the ring direction. It overlaps with parts other than 61Bb, 62Ba, and 62Bb. Similarly, when viewed from the stacking direction D1, the end portions 61Ba, 61Bb, 62Ba, 62Bb of the second divided pieces 61B, 62B are portions other than the end portions 61Aa, 61Ab, 62Aa, 62Ab of the first divided pieces 61A, 62A. It overlaps with.

(First resin part forming step)
Subsequently, the plurality of divided pieces (first divided pieces 61A and 62A and second divided pieces 61B and 62B) are welded to the edge 34a of the electrode plate 34, whereby the first resin portion 52 is formed. Although the method of welding is not particularly limited, the plurality of divided pieces can be welded to the edge 34a of the electrode plate 34 by, for example, thermal welding, ultrasonic welding, or the like.

(Lamination process)
Subsequently, the laminated body 30 is obtained by laminating the bipolar electrode 32 in which the first resin portion 52 is formed on the edge portion 34a of the electrode plate 34 as described above.

(Frame forming process)
Subsequently, the second resin portion 54 is formed by, for example, injection molding. As a result, as shown in FIG. 2, the frame 50 having the first resin portion 52 and the second resin portion 54 is formed.

[Function and effect]
The manufacturing method of the electrical storage module 12 according to the present embodiment includes a split piece acquisition step of obtaining a plurality of non-annular split pieces 60 for forming the first resin portion 52 from the sheet material F, and a view from the stacking direction D1. The ends of the divided pieces 60 in the ring direction of the first resin portion 52 (the direction along the edge 34a and the circumferential direction around the Z direction) are portions other than the ends of the other divided pieces 60 in the ring direction. The first resin portion by welding a plurality of divided pieces 60 to the edge 34a of the electrode plate 34, and a divided piece arranging step of arranging the plurality of divided pieces 60 on the edge 34a of the electrode plate 34 so as to overlap A first resin portion forming step of forming 52 and a stacking step of stacking bipolar electrodes 32 to obtain a stacked body.

  As described above with reference to FIG. 3B, when the annular resin piece 600 is directly punched from the sheet material F, the inner portion 601 of the resin piece 600 is generated as a secondary object as a disposal target, and the sheet The disposal rate of the material F will become high. On the other hand, according to the manufacturing method, since the first resin portion 52 is formed by the plurality of non-annular divided pieces 60, the resin piece 600 corresponding to the annular first resin portion 52 is directly punched from the sheet material F. Therefore, the inner portion 601 to be discarded does not occur. Further, in the manufacturing method, the end portions of the respective divided pieces 60 are arranged so as to overlap with the portions other than the end portions of the other divided pieces 60 as viewed from the stacking direction D1. Thereby, the clearance gap or the joint line between the adjacent division pieces 60 is filled appropriately at the time of welding, and the airtightness of the 1st resin part 52 is ensured. Therefore, according to the manufacturing method, it is possible to improve the yield of the first resin portion 52 (that is, reduce the discard rate of the sheet material F) while ensuring the airtightness of the first resin portion 52.

  Moreover, in this embodiment, the 1st resin part 52 is arrange | positioned on the some 1st division | segmentation piece 61A, 62A arrange | positioned at the edge part 34a of the electrode plate 34, and the some 1st division | segmentation piece 61A, 62A. A plurality of second divided pieces 61B and 62B. In the divided piece arrangement step, the first divided pieces 61A and 62A are arranged on the edge 34a of the electrode plate 34 so that the plurality of first divided pieces 61A and 62A do not overlap each other when viewed from the stacking direction D1. The divided piece arrangement step and the plurality of second divided pieces 61B and 62B do not overlap each other when viewed from the stacking direction D1, and the area (gap or gap) between the adjacent first divided pieces 61A and 62A when viewed from the stacking direction D1. The plurality of second divided pieces 61B and 62B are arranged on the plurality of first divided pieces 61A and 62A so that the region (gap or seam) between the adjacent second divided pieces 61B and 62B does not overlap. A second divided piece arranging step. According to the above configuration, the first resin portion has the two-layer structure of the first layer formed by the plurality of first divided pieces 61A and 62A and the second layer formed by the plurality of second divided pieces 61B and 62B. 52 can be formed appropriately. Specifically, the state where the region between the first divided pieces 61A and 62A in the first layer and the region between the second divided pieces 61B and 62B in the second layer are shifted from each other when viewed from the stacking direction D1. Therefore, the gap or seam between the adjacent first divided pieces 61A and 62A and the gap or seam between the second divided pieces 61B and 62B are appropriately filled, and the airtightness of the first resin portion 52 is improved. Secured.

  In the present embodiment, the first resin portion 52 has a rectangular annular shape so as to match the shape of the edge portion 34 a of the electrode plate 34. The plurality of divided pieces 60 include divided pieces 60 (in the present embodiment, first divided pieces 61A and 62A and second divided pieces 61B and 62B) formed in an L shape. In the divided piece arrangement step, the divided pieces 60 formed in an L shape are arranged at positions corresponding to the corners of the first resin portion 52. According to the said structure, it becomes possible to align the division piece 60 easily and can suppress the position shift of the division piece 60 in a division piece arrangement | positioning process.

  In addition, the power storage module 12 manufactured by the above manufacturing method includes a plurality of bipolar devices each including an electrode plate 34, a positive electrode 36 provided on one surface of the electrode plate 34, and a negative electrode 38 provided on the other surface of the electrode plate 34. A laminate 30 in which the electrodes 32 are laminated, and an annular first resin portion 52 welded to the edge portion 34a of each electrode plate 34 are provided. The first resin portion 52 is formed from a plurality of non-annular divided pieces 60. When viewed from the stacking direction D1, the end portions of the divided pieces 60 in the ring direction of the first resin portion 52 (the circumferential direction around the stacking direction D1) (in the present embodiment, the end portions 61Aa, 61Ab, 62Aa, 62Ab, 61Ba, 61Bb, 62Ba, 62Bb) overlaps with the portions other than the end portions in the ring direction of the other divided pieces 60. For example, the end 61Ab of the first divided piece 61A overlaps with a portion other than the end of the second divided piece 61B.

  In the power storage module 12, since the first resin portion 52 is formed by a plurality of non-annular divided pieces 60, an inner portion 601 to be discarded is generated when the annular resin piece 600 is directly punched from the sheet material F. do not do. Moreover, in the said electrical storage module 12, seeing from the lamination direction D1, it arrange | positions so that the edge part of each division | segmentation piece 60 in the ring direction may overlap with parts other than the edge part in the ring direction of the other division | segmentation piece 60. FIG. For this reason, the gap or seam between adjacent divided pieces 60 is appropriately filled by welding, and the airtightness of the first resin portion 52 is ensured. Therefore, according to the power storage module 12, it is possible to improve the yield of the first resin part 52 (that is, reduce the discard rate of the sheet material F) while ensuring the airtightness of the first resin part 52.

  In the present embodiment, the first resin portion 52 is formed in the first resin portion forming step before the laminating step. However, after performing the laminating step first, the first resin portion 52 is formed on each electrode plate 34 of the plurality of bipolar electrodes 32. On the other hand, you may implement said 1st resin part formation process collectively.

  In the present embodiment, the four divided pieces 60 are used in each of the first layer and the second layer. However, the number and types of the divided pieces 60 for forming each layer of the first resin portion 52 are as described above. It is not limited to examples. In the present embodiment, only the L-shaped divided piece 60 is used. However, a divided piece having a shape other than the L-shaped (for example, a strip shape) may be used. Divided pieces of shapes other than the letter shape may be mixed.

  In the present embodiment, the two divided pieces 61 and the two divided pieces 62 having different sizes are arranged in a rectangular frame shape. However, instead of the two divided pieces 61 and the two divided pieces 62, the same shape is used. And two L-shaped pieces of size may be used. Specifically, the divided piece includes a long side member having the same length as the long side of the edge portion 34a of the electrode plate 34 and a short side member having the same length as the short side of the edge portion 34a of the electrode plate 34. It is an L-shaped member similar to the split pieces 61 and 62. When the electrode plate 34 has a square shape, the long side and the short side described above coincide with each other. According to such a divided piece, a rectangular frame extending over the entire area of the edge 34a of the electrode plate 34 can be formed by arranging the two divided pieces in a rectangular frame shape (b-shaped). As a result, the number of necessary divided pieces (number of parts) is reduced compared to the case of using divided pieces 61 and 62 having different sizes as in the present embodiment or the case of using strip-shaped divided pieces. be able to. Further, since only one kind of divided piece needs to be prepared, it is not necessary to prepare a plurality of molds and production lines for obtaining the divided piece in the divided piece obtaining step.

  In the above embodiment, the first divided piece and the second divided piece have a two-layer structure including a first layer formed by a plurality of first divided pieces and a second layer formed by a plurality of second divided pieces. Although the divided pieces are arranged, when a plurality of divided pieces can be arranged without a gap, a single layer structure may be used. For example, by arranging the above-mentioned two L-shaped divided pieces in a rectangular frame shape without a gap, the annular first resin portion 52 welded to the edge portion 34a of each electrode plate 34 can be replaced with the two L-shaped pieces. It can be formed by a segmented piece.

[Modification]
With reference to FIG.6 and FIG.7, the manufacturing method of the electrical storage module 12 which concerns on a modification is demonstrated. FIG. 6B shows a cross section taken along line BB in FIG. FIGS. 7B and 7C show cross sections taken along lines BB and CC in FIG. 7A. This modified example is different from the above embodiment with respect to the divided piece acquisition step and the divided piece arrangement step, and the other steps (first resin portion forming step, laminating step, frame forming step) are the same as in the above embodiment. is there. Therefore, below, the division | segmentation piece acquisition process and division | segmentation piece arrangement | positioning process which concern on this modification are demonstrated.

(Divided piece acquisition process according to modification)
As shown in FIG. 6, in this modification, the thickness T1 of the edge F1 on both sides of the sheet material F in the width direction D3 intersecting the longitudinal direction D2 of the sheet material F is the edge on both sides of the sheet material F. The thickness is approximately half the thickness T2 of the central portion F2 between F1 (T1≈T2 / 2).

  As shown in FIG. 6B, as described above, the sheet materials F having different thicknesses at the edge portion F1 and the central portion F2 are different loads on the edge portion F1 and the central portion F2 on both sides by the rolling press. Can be generated. The sheet material F described above can also be generated by cutting the surface of the edge F1 on both sides using a laser, a scissors or the like.

  Alternatively, instead of the sheet material F formed by rolling or cutting a single sheet material as described above, as shown in FIG. A sheet material FA configured as a layered film formed by overlapping the film FA20 may be used. Here, the thickness of the upper first film FA10 and the lower second film FA20 is the same as the thickness T1 of the edge F1 of the sheet material F described above. Further, the width in the width direction D3 of the first film FA10 is the same as the width of the central portion F2 of the sheet material F described above. The width in the width direction D3 of the second film FA20 is the width of the sheet material F described above (that is, the size of the width of the edge F1 on both sides and the width of the center F2). In this case, the edge portions FA1 on both sides of the sheet material FA are formed by the edge portions of the second film FA20 (portions that do not overlap the first film FA10). Further, the central portion FA2 of the sheet material FA is formed by a portion where the first film FA10 and the second film FA20 overlap.

  In this modification, the following divided pieces 160 are acquired from the sheet material F (or the sheet material FA) described above (see FIG. 6A). That is, the two edge portions 160A of the divided piece 160 are formed by the edge portions F1 on both sides of the sheet material F, and the main body portion 160B between the two edge portions 160A of the divided piece 160 is the central portion of the sheet material F. Formed by F2. Here, the two edge portions 160 </ b> A of the divided piece 160 function as portions for connecting to the other divided pieces 160. Such a divided piece 160 is obtained, for example, by punching using a mold set so that the two edge portions 160A of the divided piece 160 are positioned at the edge portions F1 on both sides of the sheet material F. In this modified example, as shown in FIG. 6A, a strip-shaped divided piece 160 is obtained. Further, by using two types of sheet material F and a formwork having different sizes, two types of strip-shaped divided pieces 161 and 162 having different lengths are obtained (see FIG. 7).

(Divided piece arrangement process according to modification)
Subsequently, as shown in FIG. 7, a plurality of divided pieces are arranged on the edge 34a of the electrode plate 34 so that the edge 161A of the divided piece 161 and the edge 162A of the divided piece 162 overlap each other when viewed from the stacking direction D1. 161, 162 are arranged. In this modification, two divided pieces 161 constituting the long side portion of the rectangular annular first resin portion 52 and two divided pieces 162 constituting the short side portion of the first resin portion 52 are arranged.

  The divided piece 161 corresponds to a surface 161a extending in the thickness direction of the divided piece 161 so as to define a boundary between the main body portion 161B and the edge portion 161A of the divided piece 161, and an upper surface of the edge portion 161A of the divided piece 161. Surface 161b. The surface 161b extends from the lower end of the surface 161a to the distal end side of the split piece 161. Similarly, the divided piece 162 includes a surface 162a extending in the thickness direction of the divided piece 162 so as to define a boundary between the main body portion 162B and the edge portion 162A of the divided piece 162, and a lower surface of the edge portion 162A of the divided piece 162. And a surface 162b corresponding to. The surface 162b extends from the upper end of the surface 162a to the tip side of the segment piece 162. Here, “upper” indicates the positive side in the Z direction, and “lower” indicates the negative side in the Z direction.

  As shown in FIG. 7A, the surface 161b and the surface 162b are obtained by overlapping the surface 161b and the surface 162b so that the longitudinal direction of the divided piece 161 and the longitudinal direction of the divided piece 162 are orthogonal to each other. In addition, the shape and size as viewed from the stacking direction D1 (Z direction) are set in advance.

  In the divided piece 161, the side surface 161 c of the edge portion 161 </ b> A that faces the surface 162 a of the divided piece 162 corresponds to the end portion of the divided piece 161 in the ring direction (circumferential direction around the Z direction) of the first resin portion 52. Further, in the split piece 162, the side surface 162 c of the edge portion 162 </ b> A facing the surface 161 a of the split piece 161 corresponds to the end portion of the split piece 162 in the ring direction of the first resin portion 52. As shown in FIG. 7C, in the arrangement of the divided pieces 161 and 162 as described above, the side surface 161c of the divided piece 161 is thicker than the side surface 162c of the divided piece 162 when viewed from the Z direction. It overlaps with the part. Further, as shown in FIG. 7B, the side surface 162c of the divided piece 162 overlaps with a thick portion other than the side surface 161c of the divided piece 161 when viewed from the Z direction.

  Further, as shown in FIG. 7B, the thickness of the edge portions 161A and 162A of the divided pieces 161 and 162 is substantially half the thickness of the main body portions 161B and 162B of the divided pieces 161 and 162. The thickness of the portion where the edge portion 161A and the edge portion 162A overlap is substantially the same as the thickness of the main body portions 161B and 162B of the divided pieces 161 and 162.

  According to the above-described modification, the sheet material F in which the thickness T1 of the edge F1 on both sides in the width direction D3 is substantially half of the thickness T2 of the center portion F2 is removed from the other divided pieces 160 by punching or the like. The divided piece 160 in which the thickness of the two edge portions 160A for connection is approximately half the thickness of the main body portion 160B can be easily obtained. Further, the divided pieces 160 are connected to each other by the overlapping of the edge portions 160A of the adjacent divided pieces 160 (in the above modification, the overlapping of the edge portion 161A of the divided piece 161 and the edge portion 162A of the divided piece 162). Therefore, the thickness of the portion where the edge portions 160A overlap is substantially the same as the thickness of the main body portion 160B of the split piece 160. In addition, since the edge portions 160A of the adjacent divided pieces 160 are connected to each other, a plurality of divided pieces 160 can be arranged so that a gap between the adjacent divided pieces 160 is reduced. That is, according to the above modification, the plurality of divided pieces 160 can be arranged so that the thickness is constant and the gap between the divided pieces 160 is reduced. As a result, it is possible to suppress the occurrence of a step in the first resin portion 52 that may occur during welding (a step caused by a gap between the divided pieces 160), and to improve the dimensional accuracy of the power storage module 12.

  In addition, the power storage module 12 manufactured by the manufacturing method according to the present modification also has the same configuration as the power storage module 12 manufactured by the manufacturing method according to the embodiment. That is, in the power storage module 12 manufactured by the manufacturing method according to this modification, the end portions (side surfaces 161c and 162c) of the divided pieces 161 and 162 in the ring direction (circumferential direction around the stacking direction D1) when viewed from the stacking direction D1. The side surface 162c) overlaps with a portion other than the end portions in the ring direction of the other divided pieces 161 and 162. Therefore, the said electrical storage module 12 also has the effect mentioned above similarly to the electrical storage module 12 manufactured by the manufacturing method which concerns on the said embodiment.

  In the above modification, two divided pieces 161 and two divided pieces 162 are used. However, the number and types of divided pieces 160 for forming the first resin portion 52 are not limited to the above example. Moreover, in the said modification, only the strip-shaped division pieces 161 and 162 were used, However, The division piece of shapes (for example, L shape) other than a strip shape may be used, or a strip-shaped division piece and a strip. It may be mixed with divided pieces of shapes other than the shape.

  DESCRIPTION OF SYMBOLS 12 ... Power storage module, 30 ... Laminated body, 30a ... Side surface, 32 ... Bipolar electrode, 34 ... Electrode plate, 34a ... Edge, 36 ... Positive electrode, 38 ... Negative electrode, 50 ... Frame, 52 ... 1st resin part (seal Material), 54 ... second resin part, 60, 61, 62, 160, 161, 162 ... divided piece, 61A, 62A ... first divided piece, 61B, 62B ... second divided piece, 160A, 161A, 162A ... edge Part, 160B, 161B, 162B ... main body part, D1 ... lamination direction, D2 ... elongate direction, D3 ... width direction, F ... sheet material, F1 ... edge part, F2 ... center part.

Claims (5)

A laminate comprising a plurality of bipolar electrodes each including an electrode plate, a positive electrode provided on one surface of the electrode plate, and a negative electrode provided on the other surface of the electrode plate, and an edge portion of each electrode plate An annular sealing material welded to a power storage module,
Obtaining a plurality of non-annular divided pieces for forming the sealing material from a sheet material;
When viewed from the stacking direction of the laminate, the edges of the electrode plates are arranged such that the end portions of the divided pieces in the ring direction of the sealing material overlap portions other than the end portions of the other split pieces in the ring direction. Arranging a plurality of the divided pieces in a part;
Forming the sealing material by welding a plurality of the divided pieces to the edge of the electrode plate;
Laminating the bipolar electrodes to obtain a laminate;
including,
A method for manufacturing a power storage module. The sealing material includes a plurality of first divided pieces arranged on an edge portion of the electrode plate, and a plurality of second divided pieces arranged on the plurality of first divided pieces,
The step of arranging the divided pieces includes:
Arranging the plurality of first divided pieces on the edge of the electrode plate so that the plurality of first divided pieces do not overlap each other when viewed from the stacking direction;
A plurality of the second divided pieces do not overlap each other when viewed from the stacking direction, and an area between the first divided pieces adjacent to each other viewed from the stacking direction and an area between the adjacent second divided pieces are Arranging a plurality of second divided pieces on the plurality of first divided pieces so as not to overlap,
The manufacturing method of the electrical storage module of Claim 1. The thickness of the edge portions on both sides of the sheet material in the width direction intersecting the longitudinal direction of the sheet material is approximately half the thickness of the central portion between the edge portions on both sides of the sheet material,
In the step of obtaining the divided piece, two edge portions for connecting to the other divided piece of the divided piece are formed by the edge portions on both sides of the sheet material, and the two edge portions of the divided piece The divided piece is obtained so that the main body portion is formed by the central portion of the sheet material,
In the step of arranging the divided pieces, the plurality of divided pieces are arranged on the edge of the electrode plate such that the edges of the adjacent divided pieces overlap each other when viewed from the stacking direction.
The manufacturing method of the electrical storage module of Claim 1. The sealing material is a rectangular ring,
The plurality of divided pieces include divided pieces formed in an L shape,
In the step of arranging the divided pieces, the divided pieces formed in the L shape are arranged at positions corresponding to corners of the sealing material.
The manufacturing method of the electrical storage module as described in any one of Claims 1-3. A laminate formed by laminating a plurality of bipolar electrodes each including an electrode plate, a positive electrode provided on one surface of the electrode plate, and a negative electrode provided on the other surface of the electrode plate;
An annular sealing material welded to the edge of each electrode plate;
With
The sealing material is formed from a plurality of non-annular divided pieces,
When viewed from the stacking direction of the laminate, the end portions of the divided pieces in the ring direction of the sealing material overlap with portions other than the end portions in the ring direction of the other divided pieces.
Power storage module.

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