JP2020087870A - Manufacturing method of power storage module - Google Patents

Abstract

To provide a manufacturing method of a power storage module capable of suppressing a sealing failure of a sealing body by eliminating a gap between resin parts.SOLUTION: A manufacturing method of a power storage module includes an arranging step of arranging a first sealing portion (resin portion) 21 along an edge portion 15c of an electrode plate 15 forming a bipolar electrode 14, a pressure bonding step of pressure-bonding the first sealing portion 21 to the edge portion 15c of the electrode plate 15 using a belt sealer 41, and in the arranging step, a gap 32 between the first sealing portions 21 is formed in a direction intersecting the extending direction of the first sealing portion 21, and in the pressure bonding step, the progress direction of the pressure-bonding by the belt sealer 41 intersects with the direction in which the gap 32 is formed.SELECTED DRAWING: Figure 8

Description

The present disclosure relates to a method of manufacturing a power storage module.

An example of the power storage module is described in Patent Document 1. This electricity storage module is a bipolar battery including a plurality of stacked bipolar electrodes. The bipolar electrode has an electrode plate, a positive electrode layer provided on one surface of the electrode plate, and a negative electrode layer provided on the other surface of the electrode plate. The bipolar battery includes a sealing body that covers the outside of the battery element. The sealing body liquid-tightly seals the battery element so that the electrolytic solution inside the battery does not leak outside.

JP, 2011-151016, A

In the electricity storage module as described above, a frame-shaped resin portion may be bonded to the edge portion of the electrode plate of the bipolar electrode, and the bipolar electrodes with the frame-shaped resin portion may be laminated to form a component of the sealed body. Conceivable. At the time of this connection, if a gap is formed between the resin portions at the edge portion of the electrode plate, it may cause defective sealing of the sealing body.

The present disclosure has been made to solve the above problems, and an object of the present disclosure is to provide a method of manufacturing an electricity storage module that can suppress a sealing failure of a sealing body by eliminating a gap between resin parts.

A method of manufacturing an electricity storage module according to an aspect of the present disclosure includes an arrangement step of arranging a resin portion along an edge portion of an electrode plate, and a pressure bonding step of pressure-bonding the resin portion to the edge portion of the electrode plate using a belt sealer. In the arranging step, the gap between the resin portions is formed in a direction intersecting the extending direction of the resin portions, and in the joining step, the advancing direction of the pressure bonding by the belt sealer intersects the gap forming direction.

In this method of manufacturing an electricity storage module, the direction in which the pressure is applied by the belt sealer intersects the direction in which the gap is formed. When the resin portion is pressure-bonded using the belt sealer, the resin forming the resin portion expands in the traveling direction of the belt sealer due to the pressure bonding. By filling the gaps between the resin parts with the stretched resin, the gaps between the resin parts are eliminated, and defective sealing of the sealing body can be suppressed.

In addition, in the crimping step, a gap may be positioned on the downstream side in the traveling direction of the crimping by the belt sealer. On the downstream side in the direction of progress of pressure bonding by the belt sealer, the resin is significantly stretched, and the stretched resin can fill the gap between the resin portions more reliably.

Further, the electrode plate has a rectangular shape, and in the arranging step, a frame-shaped resin portion may be arranged on the edge portion of the electrode plate using a plurality of strip-shaped resin pieces. In this case, it is possible to reduce the amount of waste of the base material as compared with the method of punching the frame-shaped resin portion from the sheet-shaped base material.

The number of gaps formed per side of the electrode plate may be 2 or less. By limiting the number of gaps formed, it is possible to more reliably fill the gaps between the resin portions with the stretched resin.

According to the present disclosure, it is possible to suppress the sealing failure of the sealing body by eliminating the gap between the resin portions.

FIG. 3 is a schematic cross-sectional view showing a power storage device including the power storage module according to the present embodiment. It is a schematic sectional drawing which shows the internal structure of an electrical storage module. It is a flow chart which shows an example of the manufacturing process of an electricity storage module. It is a flow chart which shows an example of a layered product formation process. It is a schematic plan view which shows an example of the frame-shaped resin part in an arrangement process. It is a schematic side view which shows the structural example of the belt sealer used in a pressure bonding process. It is a schematic plan view which shows the advancing direction of pressure bonding by a belt sealer. It is a principal part enlarged view of the clearance vicinity. It is a schematic plan view which shows another example of the frame-shaped resin part in an arrangement process.

Hereinafter, preferred embodiments of a method for manufacturing an electricity storage module according to one aspect of the present disclosure will be described in detail with reference to the drawings.

FIG. 1 is a schematic cross-sectional view showing an embodiment of a power storage device. Power storage device 1 shown in FIG. 1 is used as a battery in various vehicles such as forklifts, hybrid vehicles, electric vehicles, and the like. The power storage device 1 includes a module stack 2 including a plurality of stacked power storage modules 4, and a restraining member 3 that applies a restraining load to the module stack 2 in the stacking direction of the module stack 2.

The module stack 2 includes a plurality (here, three) of power storage modules 4 and a plurality (here, four) of conductive plates 5. The power storage module 4 is a bipolar battery and has a rectangular shape when viewed from the stacking direction. The electricity storage module 4 is, for example, a secondary battery such as a nickel hydrogen secondary battery or a lithium ion secondary battery, or an electric double layer capacitor. In the following description, a nickel-hydrogen secondary battery will be exemplified.

The electricity storage modules 4 adjacent to each other in the stacking direction are electrically connected to each other via the conductive plate 5. The conductive plates 5 are arranged between the power storage modules 4 adjacent to each other in the stacking direction and outside the power storage module 4 located at the stacking end. A positive electrode terminal 6 is connected to one of the conductive plates 5 arranged outside the power storage module 4 located at the stacking end. The negative electrode terminal 7 is connected to the other conductive plate 5 arranged outside the power storage module 4 located at the stacking end. The positive electrode terminal 6 and the negative electrode terminal 7 are drawn out, for example, from the edge of the conductive plate 5 in a direction intersecting with the stacking direction. The power storage device 1 is charged and discharged by the positive electrode terminal 6 and the negative electrode terminal 7.

Inside the conductive plate 5, a plurality of flow paths 5a for circulating a refrigerant such as air are provided. The flow path 5a extends, for example, along a direction that intersects (orthogonally) with the stacking direction and the withdrawal direction of the positive electrode terminal 6 and the negative electrode terminal 7. The conductive plate 5 has a function as a connecting member that electrically connects the power storage modules 4 to each other, and also functions as a heat dissipation plate that radiates the heat generated in the power storage module 4 by circulating a refrigerant in these flow paths 5a. It also has functions. In the example of FIG. 1, the area of the conductive plate 5 viewed from the stacking direction is smaller than the area of the electricity storage module 4, but from the viewpoint of improving heat dissipation, the area of the electrically conductive plate 5 is 4 may be the same as the area of the electricity storage module 4 or may be larger than the area of the electricity storage module 4.

The restraint member 3 includes a pair of end plates 8 that sandwich the module stack 2 in the stacking direction, and a fastening bolt 9 and a nut 10 that fasten the end plates 8 together. The end plate 8 is a rectangular metal plate having an area that is slightly larger than the areas of the power storage module 4 and the conductive plate 5 when viewed in the stacking direction. A film F having electrical insulation is provided on the surface of the end plate 8 on the module laminate 2 side. The film F insulates the end plate 8 and the conductive plate 5 from each other.

The edge of the end plate 8 is provided with an insertion hole 8a at a position outside the module laminate 2. The fastening bolt 9 is passed from the insertion hole 8a of the one end plate 8 toward the insertion hole 8a of the other end plate 8, and the tip end portion of the fastening bolt 9 protruding from the insertion hole 8a of the other end plate 8 is The nut 10 is screwed. As a result, the power storage module 4 and the conductive plate 5 are sandwiched by the end plates 8 to be unitized as the module laminated body 2, and a restraining load is applied to the module laminated body 2 in the laminating direction.

Next, the configuration of the power storage module 4 will be described in detail. FIG. 2 is a schematic cross-sectional view showing the internal configuration of the electricity storage module shown in FIG. As shown in FIG. 2, the electricity storage module 4 includes an electrode stack 11 and a resin sealing body 12 that seals the electrode stack 11. The electrode stacked body 11 is configured by a plurality of electrodes stacked along the stacking direction D of the power storage module 4 via the separator 13. These electrodes include a stacked body of a plurality of bipolar electrodes 14, a negative electrode termination electrode 18, and a positive electrode termination electrode 19.

The bipolar electrode 14 has an electrode plate 15 including one surface 15a and the other surface 15b opposite to the one surface 15a, a positive electrode 16 provided on the one surface 15a, and a negative electrode 17 provided on the other surface 15b. ing. The positive electrode 16 is a positive electrode active material layer formed by applying the positive electrode active material to the electrode plate 15. The negative electrode 17 is a negative electrode active material layer formed by applying the negative electrode active material to the electrode plate 15. In the electrode stacked body 11, the positive electrode 16 of one bipolar electrode 14 faces the negative electrode 17 of another bipolar electrode 14 adjacent in one of the stacking directions D with the separator 13 interposed therebetween. In the electrode stacked body 11, the negative electrode 17 of one bipolar electrode 14 faces the positive electrode 16 of another bipolar electrode 14 adjacent to the other in the stacking direction D with the separator 13 interposed therebetween.

The negative terminal electrode 18 has an electrode plate 15 and a negative electrode 17 provided on the other surface 15b of the electrode plate 15. The negative terminal electrode 18 is arranged at one end in the stacking direction D such that the other surface 15b faces the center side in the stacking direction D of the electrode stack 11. One surface 15a of the electrode plate 15 of the negative terminal electrode 18 constitutes one outer surface in the stacking direction of the electrode stack 11, and is electrically connected to the one conductive plate 5 (see FIG. 1) adjacent to the power storage module 4. It is connected. The negative electrode 17 provided on the other surface 15b of the electrode plate 15 of the negative terminal electrode 18 faces the positive electrode 16 of the bipolar electrode 14 at one end in the stacking direction D via the separator 13.

The positive electrode termination electrode 19 has an electrode plate 15 and a positive electrode 16 provided on one surface 15 a of the electrode plate 15. The positive electrode termination electrode 19 is arranged at the other end in the stacking direction D so that the one surface 15a faces the center side in the stacking direction D in the electrode stack 11. The positive electrode 16 provided on the one surface 15 a of the positive electrode termination electrode 19 faces the negative electrode 17 of the bipolar electrode 14 at the other end in the stacking direction D via the separator 13. The other surface 15b of the electrode plate 15 of the positive electrode termination electrode 19 constitutes the other outer surface in the stacking direction of the electrode stack 11, and is electrically connected to the other conductive plate 5 (see FIG. 1) adjacent to the power storage module 4. It is connected.

The electrode plate 15 is made of a metal such as nickel or a nickel-plated steel plate. As an example, the electrode plate 15 is a rectangular metal foil made of nickel. The edge portion 15c of the electrode plate 15 has a rectangular frame shape and is an uncoated region where the positive electrode active material and the negative electrode active material are not coated. Examples of the positive electrode active material forming the positive electrode 16 include nickel hydroxide. Examples of the negative electrode active material forming the negative electrode 17 include a hydrogen storage alloy. In the present embodiment, the formation area of the negative electrode 17 on the other surface 15b of the electrode plate 15 is slightly larger than the formation area of the positive electrode 16 on the one surface 15a of the electrode plate 15.

The separator 13 is formed in a sheet shape, for example. Examples of the separator 13 include a porous film made of a polyolefin resin such as polyethylene (PE) and polypropylene (PP), and a woven or non-woven fabric made of polypropylene, methylcellulose and the like. The separator 13 may be reinforced with a vinylidene fluoride resin compound.

The sealing body 12 is formed of, for example, an insulating resin into a rectangular tubular shape as a whole. The sealing body 12 is provided on the side surface 11 a of the electrode laminate 11 so as to surround the edge portion 15 c of the electrode plate 15. The sealing body 12 holds the edge portion 15c on the side surface 11a. The sealing body 12 surrounds the plurality of first sealing portions 21 joined to the edge portion 15c of the electrode plate 15 and the first sealing portion 21 from the outside along the side surface 11a. And a second sealing portion 22 coupled to each of the above. The first sealing portion 21 and the second sealing portion 22 are, for example, an insulating resin having alkali resistance. Examples of the constituent material of the first sealing portion 21 and the second sealing portion 22 include polypropylene (PP), polyphenylene sulfide (PPS), modified polyphenylene ether (modified PPE), and the like.

The first sealing portion 21 is continuously provided on the one surface 15a of the electrode plate 15 over the entire circumference of the edge portion 15c, and has a rectangular frame shape when viewed from the stacking direction D. In the present embodiment, the first sealing portion 21 is provided not only for the electrode plate 15 of the bipolar electrode 14, but also for the electrode plate 15 of the negative electrode termination electrode 18 and the electrode plate 15 of the positive electrode termination electrode 19. In the negative terminal electrode 18, the first sealing portion 21 is provided on the edge portion 15c of the one surface 15a of the electrode plate 15, and in the positive terminal electrode 19, both edge portions of the one surface 15a and the other surface 15b of the electrode plate 15 are provided. The first sealing portion 21 is provided at 15c.

The first sealing portion 21 is hermetically bonded to the one surface 15a of the electrode plate 15 by, for example, thermocompression bonding. The first sealing portion 21 is, for example, a film having a predetermined thickness in the stacking direction D. The inside of the first sealing portion 21 is located between the edge portions 15c of the electrode plates 15 adjacent to each other in the stacking direction D. The outer side of the first sealing portion 21 projects beyond the edge of the electrode plate 15, and the tip portion thereof is embedded in the second sealing portion 22. The first sealing portions 21 adjacent to each other along the stacking direction D may be separated from each other or may be in contact with each other. The outer edge portions of the first sealing portion 21 may be joined to each other by, for example, hot plate welding.

An area where the electrode plate 15 and the first sealing portion 21 overlap is a coupling area K between the electrode plate 15 and the first sealing portion 21. In the joining region K, the surface of the electrode plate 15 is roughened. The roughened area may be only the bonding area K, but in the present embodiment, the entire surface of the electrode plate 15 is roughened. The roughening can be realized by forming a plurality of protrusions by electrolytic plating, for example. By forming the plurality of protrusions, the resin in a molten state enters between the plurality of protrusions formed by roughening at the bonding interface between the electrode plate 15 and the first sealing portion 21, and the anchor effect is exerted. It Thereby, the bonding strength between the electrode plate 15 and the first sealing portion 21 can be improved. The protrusion formed during roughening has, for example, a convex portion formed on the surface of the electrode plate 15 as a base end, and has a shape that is tapered from the base end toward the tip side. As a result, the cross-sectional shape between the adjacent protrusions becomes an undercut shape, and the anchor effect can be enhanced.

The second sealing portion 22 is provided outside the electrode laminated body 11 and the first sealing portion 21, and constitutes the outer wall (housing) of the power storage module 4. The second sealing portion 22 is formed, for example, by resin injection molding, and extends along the stacking direction D over the entire length of the electrode stacked body 11. The second sealing portion 22 has a rectangular frame shape extending in the stacking direction D as an axial direction. The second sealing portion 22 is welded to the outer surface of the first sealing portion 21 by heat during injection molding, for example.

The first sealing portion 21 and the second sealing portion 22 form an internal space V between adjacent electrodes and seal the internal space V. More specifically, the second sealing portion 22 and the first sealing portion 21 are arranged between the bipolar electrodes 14 adjacent to each other along the stacking direction D, and the negative electrode termination electrodes 18 adjacent to each other along the stacking direction D. And the bipolar electrode 14, and between the positive electrode terminal electrode 19 and the bipolar electrode 14 which are adjacent to each other along the stacking direction D are sealed. As a result, airtightly partitioned internal spaces V are formed between the adjacent bipolar electrodes 14, between the negative electrode termination electrode 18 and the bipolar electrode 14, and between the positive electrode termination electrode 19 and the bipolar electrode 14. ing. In this internal space V, an electrolytic solution (not shown) containing an alkaline solution such as an aqueous solution of potassium hydroxide is contained. The electrolytic solution is impregnated in the separator 13, the positive electrode 16, and the negative electrode 17.

Subsequently, a method of manufacturing the above-described power storage module 4 will be described. FIG. 3 is a flowchart showing an example of the manufacturing process of the power storage module. As shown in the figure, the manufacturing process of the electricity storage module 4 includes a laminated body forming step (step S01), a sealing body forming step (step S02), an electrolytic solution injecting step (step S03), and an assembling step (step S04). ) And are configured.

In the laminated body forming step, the electrode laminated body 11 is formed. In the laminated body forming step, first, the bipolar electrodes 14 are laminated via the separator 13 to obtain a laminated body. Next, the negative electrode termination electrode 18 and the positive electrode termination electrode 19 are further laminated|stacked on the lamination|stacking edge of the said laminated body via the separator 13, and the electrode laminated body 11 is obtained. In stacking, the rectangular frame-shaped first sealing portion 21 is previously bonded to the edge portions 15c of the electrode plates 15 of the bipolar electrode 14, the negative electrode termination electrode 18, and the positive electrode termination electrode 19 by thermocompression bonding or the like. Is preferred. Details will be described later.

In the sealing body forming step, the second sealing section 22 is formed on the electrode laminate 11 by injection molding, for example, to form the sealing body 12. Specifically, the electrode laminated body 11 obtained in the laminated body forming step is placed in a mold, and the resin material of the second sealing portion 22 having fluidity is poured into the mold to obtain the electrode laminated body. The second sealing portion 22 is formed on the side surface 11 a of the side wall 11. The first sealing portions 21 of the electrode laminated body 11 are bonded to each other by the second sealing portion 22 to obtain the sealing body 12.

In the electrolytic solution injecting step, the electrolytic solution is injected into each of the internal spaces V of the electrode laminate 11. Here, in injecting the electrolytic solution, for example, the electrolytic solution is injected into the internal space V via an injection port (not shown) provided in the side surface 12a of the sealing body 12. After the injection of the electrolytic solution, the injection port is sealed with a sealing material or the like to obtain the electricity storage module 4. Instead of the sealing material, a pressure adjusting valve or the like may be provided at the inlet.

In the assembly process, first, the plurality of power storage modules 4 are stacked with the conductive plate 5 interposed therebetween. At this time, it is preferable to connect the positive electrode terminal 6 to the conductive plate 5 arranged on one side of the stacking direction D in advance and to connect the negative electrode terminal 7 to the conductive plate 5 arranged on the other side in advance. Next, the pair of end plates 8, 8 is arranged at both ends of the electricity storage module 4 in the stacking direction D with the film F having electrical insulation properties interposed therebetween. Then, the fastening bolt 9 is inserted into the insertion hole 8 a of the end plate 8, and the nut 10 is screwed to the tip of the fastening bolt 9 protruding from the end plate 8. As a result, the plurality of power storage modules 4 are unitized to obtain the power storage device 1.

Then, the above-mentioned laminated body forming step will be described in more detail.

FIG. 4 is a flowchart showing an example of the laminated body forming process. As shown in the figure, the laminated body forming process includes an arranging process (step S11), a pressure bonding process (step S12), and a laminating process (step S13).

In the placement step, the frame-shaped first sealing portion (resin portion) 21 is placed along the edge portion 15c of the electrode plate 15. Here, as shown in FIG. 5, the frame-shaped first sealing portion 21 is arranged on the edge portion 15c of the electrode plate 15 by using a plurality of strip-shaped resin pieces 31. In the example of FIG. 5, the resin piece 31 includes a pair of resin pieces 31A and 31A corresponding to the long side 15A of the electrode plate 15 and a pair of resin pieces 31B and 31B corresponding to the short side 15B of the electrode plate 15. Has been done. The resin piece 31A extends along the long side 15A of the electrode plate 15 so as to overlap with one corner portion 15C of the electrode plate 15 which is diagonally located. Further, the pair of resin pieces 31B extends along the short side 15B of the electrode plate 15 so as to overlap with the other corner portion 15D diagonally located on the electrode plate 15.

A gap 32 is formed between the resin pieces 31, 31. More specifically, on the long side 15A of the electrode plate 15, a gap 32A is formed between the resin piece 31A and the resin piece 31B in the vicinity of the corner 15D. The gap 32A has a width sufficiently smaller than the width of the resin piece 31A and is formed in a direction orthogonal to the extending direction of the resin piece 31A. Further, on the short side 15B of the electrode plate 15, a gap 32B is formed between the resin piece 31B and the resin piece 31A, close to the corner portion 15C. The gap 32B has a width sufficiently smaller than the width of the resin piece 31B and is formed in a direction orthogonal to the extending direction of the resin piece 31B. In this embodiment, the number of the gaps 32 formed per side of the electrode plate 15 is one.

In the crimping step, the resin pieces 31A and 31B are crimped to the edge portion 15c of the electrode plate 15 using the belt sealer 41. As shown in FIG. 6, for example, the belt sealer 41 includes a first belt 42A and a second belt 42B, a heating block 43, a pressure bonding roller 44, and a cooling block 45.

The first belt 42A and the second belt 42B are arranged vertically in two stages with respect to the work (the electrode plate 15 with the resin piece 31). The first belt 42A and the second belt 42B are circularly driven in opposite directions by a pair of pulleys 46, 46, and a work is horizontally fixed between the first belt 42A and the second belt 42B. It is designed to be transported at a speed.

The heating blocks 43 are arranged vertically in a pair on the upstream side in the transport direction of the first belt 42A and the second belt 42B. A spring 47 is attached to each of the upper and lower heating blocks 43, 43, and is biased so as to sandwich the work conveyed between the first belt 42A and the second belt 42B. The heating block 43 melts the resin piece 31 on the edge portion 15c of the electrode plate 15.

The pressure bonding rollers 44 are arranged between the heating block 43 and the cooling block 45 in a pair in the upper and lower directions. A spring 47 is attached to each of the upper and lower pressure-bonding rollers 44, 44, and is biased so as to sandwich the work conveyed between the first belt 42A and the second belt 42B. The pressure bonding roller 44 pressure-bonds the melted resin piece 31 to the edge portion 15c of the electrode plate 15.

The cooling blocks 45 are arranged in a pair in the upper and lower sides on the downstream side in the transport direction of the first belt 42A and the second belt 42B. A spring 47 is attached to each of the upper and lower cooling blocks 45, 45, and is biased so as to sandwich the work conveyed between the first belt 42A and the second belt 42B. The cooling block 45 fixes the molten resin piece 31 to the edge portion 15c of the electrode plate 15.

FIG. 7 is a schematic plan view showing a traveling direction of pressure bonding by the belt sealer. As shown in the figure, in the crimping step, the advancing direction of crimping by the belt sealer 41 intersects the forming direction of the gap 32. That is, when the pressure bonding on the long side 15A side of the electrode plate 15 is performed, the advancing direction of the pressure bonding (arrow A in FIG. 7) is orthogonal to the gap 32A formed in the direction orthogonal to the extending direction of the resin piece 31A, and the electrode When performing crimping on the short side 15B side of the plate 15, the advancing direction of the crimping (arrow B in FIG. 7) is made orthogonal to the gap 32B formed in the direction orthogonal to the extending direction of the resin piece 31B.

Further, as shown in FIG. 7, in the crimping step, the gap 32 is positioned on the downstream side in the advancing direction of the crimping by the belt sealer 41. Here, the downstream side in the traveling direction refers to the end point side with respect to the midpoint between the start point and the end point of pressure bonding. When crimping the long side 15A side of the electrode plate 15, the crimping proceeds from the corner portion 15C to the corner portion 15D. When crimping the short side 15B side of the electrode plate 15, the crimping proceeds from the corner 15D to the corner 15C (arrow B in FIG. 7). As a result, as shown in FIG. 8, the resin forming the resin piece 31 extends toward the traveling direction of the belt sealer 41 by pressure bonding. By filling the gap 32 between the resin pieces 31 with the expanded resin R, the gap 32 between the resin pieces 31 is eliminated, and the frame-shaped first sealing portion 21 is formed on the edge portion 15c of the electrode plate 15. It Note that, in FIG. 7, the stretched resin R is provided with a wavy line for convenience of description, but in reality, the stretched resin R and the resin pieces 31A and 31B are integrated to the extent that it is difficult to distinguish the boundary. Can be converted.

In the laminating step, the electrode plate 15 with the first sealing portion 21 obtained in the pressure bonding step is laminated with the separator 13 in between. A positioning jig or the like is preferably used for stacking the electrode plates 15 with the first sealing portion 21. The laminated body forming step is completed by obtaining the electrode laminated body 11 by laminating.

As described above, in the method of manufacturing the electricity storage module, the direction in which the pressure is applied by the belt sealer 41 advances in the direction in which the gap 32 is formed. When the resin piece 31 is pressure-bonded using the belt sealer 41, the resin forming the resin piece 31 extends in the traveling direction side of the belt sealer 41 by pressure bonding. By filling the gap between the resin pieces 31, 31 with the stretched resin R, the gap 32 between the resin pieces 31, 31 is eliminated, and the sealing failure of the sealing body 12 can be suppressed.

Further, in the present embodiment, the gap 32 is located on the downstream side in the advancing direction of the pressure bonding by the belt sealer 41 in the pressure bonding step. At the downstream side in the direction of progress of the pressure bonding by the belt sealer 41, the elongation of the resin becomes remarkable. Therefore, the gap 32 between the resin pieces 31, 31 can be more surely filled with the stretched resin.

Further, in the present embodiment, the electrode plate 15 has a rectangular shape, and in the arranging step, the frame-shaped first sealing is applied to the edge portion 15c of the electrode plate 15 by using the plurality of strip-shaped resin pieces 31A and 31B. The part 21 is arranged. In this case, it is possible to reduce the amount of waste of the base material as compared with the method of punching the frame-shaped first sealing portion 21 from the sheet-shaped base material.

Further, in the present embodiment, the number of the gaps 32 formed per side of the electrode plate 15 is 2 or less (1 in the present embodiment). By limiting the number of the gaps 32 formed, the stretched resin R can more reliably fill the gap 32 between the resin pieces 31, 31.

From the viewpoint of preventing a gap between the resin pieces, a method of overlapping a part of the resin pieces may be considered. However, in this case, there is a problem in that the thickness of the resin piece varies between the overlapping portion and other portions. On the other hand, in the present embodiment, by forming a gap between the resin pieces, it is possible to reduce the requirements such as the dimensional tolerance of the resin pieces and the positioning accuracy, and to fill the gap by utilizing the elongation of the resin at the time of crimping. As a result, it is possible to suppress the occurrence of variations in the thickness of the resin pieces.

The present disclosure is not limited to the above embodiment. For example, the arrangement of the resin pieces 31 is not limited to the example of FIG. 5, and various modifications can be adopted. For example, as shown in FIG. 9, the resin piece 31A extends along the long side 15A of the electrode plate 15 from the corner 15C to the corner 15D, and the resin piece 31B extends along the short side 15B of the electrode plate 15. It may extend between 31A and 31A. In this example, the resin piece 31B does not overlap any of the corner portions 15C and 15D, and two gaps 32B are formed between the resin piece 31A and the resin piece 31B on the short side 15B side of the electrode plate 15. Even in such a configuration, the gap R between the resin pieces 31 and 31 is eliminated by filling the gap between the resin pieces 31 and 31 with the stretched resin R, so that the sealing failure of the sealing body 12 may occur. Suppression is achieved.

4... Electric storage module, 15... Electrode plate, 15c... Edge part, 21... 1st sealing part (resin part), 31 (31A, 31B)... Resin piece, 32 (32A, 32B)... Gap, 41... Belt sealer ..

Claims (4)

An arranging step of arranging the resin portion along the edge of the electrode plate,
A pressure-bonding step of pressure-bonding the resin portion to the edge portion of the electrode plate using a belt sealer,
In the disposing step, a gap between the resin portions is formed in a direction intersecting the extending direction of the resin portions,
In the crimping step, a method of manufacturing an electricity storage module in which a proceeding direction of crimping by the belt sealer intersects a gap forming direction. 2. The method of manufacturing an electricity storage module according to claim 1, wherein in the crimping step, the gap is located on a downstream side in a traveling direction of crimping by the belt sealer. The electrode plate has a rectangular shape,
3. The method of manufacturing an electricity storage module according to claim 1, wherein in the arranging step, a frame-shaped resin portion is arranged at an edge portion of the electrode plate using a plurality of strip-shaped resin pieces. The method for manufacturing an electricity storage module according to claim 3, wherein the number of the gaps formed per side of the electrode plate is 2 or less.

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