JP2018174079A - Power storage module and manufacturing method thereof - Google Patents

Abstract

A power storage module including a seal portion having a novel configuration and a method for manufacturing the same are provided.
According to a power storage module and a method for manufacturing the same, a relative displacement of a plurality of frame bodies constituting a first seal portion is suppressed by heat-sealing an outer peripheral surface. Therefore, when the communication port 70 is used as an electrolyte solution injection port or a gas venting safety valve, a situation in which those functions are impaired is effectively suppressed.
[Selection] Figure 7

Description

  The present invention relates to a power storage module and a method for manufacturing the same.

  In Patent Document 1, a power generation element in which a positive electrode and a negative electrode are laminated via an electrolyte layer including a separator in an internal space formed by a seal portion, and a current collector connected to each of the positive electrode and the negative electrode are internally provided. In addition, a battery including a tube that connects an internal space and an external space of a seal portion is disclosed. The tube is used for injecting the electrolytic solution into the internal space, and also functions as a gas venting safety valve when the internal pressure increases.

JP 2004-178909 A

  In the configuration according to the related art described above, since the tube is provided in the seal portion, the tube is displaced due to displacement, deformation, breakage, or the like of the sea tube, or due to a relative displacement of the components of the seal portion that holds the tube. There is a possibility that the function of the system is damaged.

  As a result of intensive studies, the inventors have newly found a seal part configuration that can function as an electrolyte injection port and a gas venting safety valve, and that can reliably maintain the function.

  An object of this invention is to provide the electrical storage module provided with the seal | sticker part which has a novel structure, and its manufacturing method.

  In a power storage module according to one aspect of the present invention, 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 interposed via a separator. And a frame body that extends in the stacking direction of the stacked body so as to accommodate the stacked body and that is joined to the periphery of each electrode plate of the plurality of bipolar electrodes in the stacking direction of the stacked body. And a sealing member having a cylindrical sealing portion configured to be overlapped, wherein the sealing end surface of the sealing portion constituted by the peripheral end surfaces of adjacent frames in the stacking direction of the stacked body is a heat welding surface In addition, a communication port that penetrates the seal portion in a direction orthogonal to the stacking direction is provided between the adjacent frames in the stacking direction on the seal end surface of the seal portion.

  The power storage module includes a seal portion having a novel configuration in which a seal end surface is a heat welding surface and a communication port is provided in the seal end surface. Since the relative position shift of the plurality of frames constituting the seal portion is suppressed because the end face of the seal is thermally welded, for example, when using the communication port as an electrolyte injection port or a gas venting safety valve, The situation where the function is impaired is effectively suppressed.

  The communication port includes a liquid injection port (that is, an electrolyte solution injection port) for injecting an electrolyte into the seal portion, and a pressure adjustment valve (that is, a gas vent safety valve) that opens and closes according to the internal pressure in the seal portion. It can be used as both or either one.

  A method for manufacturing an energy storage module according to one aspect of the present invention includes 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 laminated body laminated via a separator, and a frame body that extends in the lamination direction of the laminated body so as to accommodate the laminated body and that is joined to the periphery of each electrode plate of the plurality of bipolar electrodes And a sealing member having a cylindrical sealing portion configured to be stacked in a stacking direction, wherein the frame body is joined to the peripheral portion of each electrode plate of the plurality of bipolar electrodes. Lamination process of laminating bipolar electrode units via separators, thermal welding process of thermally welding seal end surfaces formed by peripheral edge surfaces of adjacent frames in the lamination direction of the laminated body, and heat-sealed seal The face, and a communication port forming step of providing a communication port extending through the sealing portion in a direction perpendicular to the stacking direction between the frame adjacent in the stacking direction.

  In the method for manufacturing the power storage module, the power storage module provided with the seal portion having a novel structure is obtained by heat-sealing the seal end surface in the heat welding step and providing a communication port on the seal end surface in the communication port forming step. can get. Since the seal end face is thermally welded, the relative position shift of the plurality of frames constituting the seal portion is suppressed. For example, when the communication port is used as an electrolyte injection port or a gas venting safety valve, their functions are The situation of damage is effectively suppressed.

  In the method for manufacturing an electricity storage module according to another aspect, in the stacking step, a plurality of bipolar electrode units are stacked by interposing a nesting extending from the inside of the frame body to the outside of the frame between adjacent frame bodies in the stacking direction. Then, in the heat welding step, the seal end face of the seal portion is heat welded with the insert interposed, and in the communication port forming step, the insert is removed from the seal portion where the seal end face is heat welded. In this case, nesting is used when providing the communication port. At this time, since the dimension of the communication port provided is the same as the outer diameter dimension of the nesting, the dimension of the communication port can be easily adjusted by adjusting the outer diameter dimension of the nesting.

  In the method for manufacturing an energy storage module according to another embodiment, in the stacking step, a plurality of nested electrode frames are stacked between different frames of the plurality of bipolar electrode units to stack a plurality of bipolar electrode units. The outer end portion does not overlap in the stacking direction of the stack. In this case, the operation | work at the time of removing a several nest | insert in a communicating port formation process becomes easy. For example, it is possible to cause the gripper of the automatic machine to grip the outer end of the nesting frame and to remove the plurality of nestings in sequence, thereby facilitating automation in the manufacture of the power storage module.

  In the method for manufacturing an electricity storage module according to another aspect, in the stacking step, the plurality of nestings protrude from the same frame body position to the outside of the frame in the stacking direction of the stack, and the protrusion length protrudes from the frame body to the outside of the frame. Intervene differently. Or in a lamination process, a plurality of nesting is interposed so that it may protrude outside a frame from a different frame position about the peripheral direction of a frame. With such an aspect, it is possible to prevent the end portions on the outer side of the plurality of nested frames from overlapping in the stacking direction of the stacked body.

  In the method for manufacturing an energy storage module according to another embodiment, in the stacking step, a plurality of nested electrode frames are stacked between different frames of the plurality of bipolar electrode units to stack a plurality of bipolar electrode units. The outer end portion overlaps in the stacking direction of the stacked body, and a through-hole that overlaps in the stacking direction of the stacked body is provided at each end portion of the plurality of nests. In this case, the operation | work at the time of removing a several nest | insert in a communicating port formation process becomes easy. For example, since the plurality of inserts can be sequentially removed by holding the outer end of the insert frame by the gripper of the automatic machine, automation in the manufacture of the power storage module is promoted.

  In the manufacturing method of the electrical storage module which concerns on another form, the frame body of the part which contact | connects this insert is fuse | melted by heating a nest | insert in a heat welding process, and the seal end surface around a communicating port is heat-welded. Even if it is difficult to sufficiently heat-seal the seal end surface around the communication port, by heating the nest and melting the part of the frame that contacts the nest, the seal end surface around the communication port Sufficient heat welding treatment can be performed.

  In the manufacturing method of the electrical storage module which concerns on another form, a hot plate, a hot air, or a laser is used for the heat welding of the seal end surface in a heat welding process.

  ADVANTAGE OF THE INVENTION According to this invention, the electrical storage module provided with the seal | sticker part which has a novel structure, and its manufacturing method are provided.

It is a schematic sectional drawing which shows embodiment of an electrical storage apparatus provided with an electrical storage module. It is a schematic sectional drawing which shows the electrical storage module which comprises the electrical storage apparatus of FIG. FIG. 3 is an exploded cross-sectional view illustrating a configuration of a first seal portion of the power storage module in FIG. 2. It is sectional drawing which follows the IV-IV line of FIG. 3 is a flowchart illustrating a procedure for manufacturing the power storage device of FIG. 1. It is the figure which showed the mode of the lamination process. It is the figure which showed the mode of the heat welding process. It is sectional drawing which showed the mode of the heat welding process. It is sectional drawing which showed the mode of the communicating port formation process. It is the figure which showed the mode of the communication port formation process of a different aspect. It is the figure which showed the mode of the communication port formation process of a different aspect.

  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.

  An embodiment of a power storage device will be described with reference to FIG. The power storage device 10 shown in FIG. 1 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 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. When viewed from the stacking direction, 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 (Z direction) of the power storage modules 12. 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. In the stacking direction, 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. 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 or gas 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. When viewed from the stacking direction, 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. 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, 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. When viewed from the stacking direction, an insertion hole 16A1 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 16 </ b> B <b> 1 through which the shaft part of the bolt 18 is inserted is provided at a position on the outer side of the power storage module 12 at the edge of the restraint plate 16 </ b> B when viewed from the stacking direction. When each restraint plate 16A, 16B has a rectangular shape when viewed from the stacking direction, the insertion hole 16A1 and the insertion hole 16B1 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 16A1 and the insertion hole 16B1 from the one restraint plate 16A side toward the other restraint plate 16B side. A nut 20 is screwed onto the tip of the bolt 18 protruding from the other restraining plate 16B. Accordingly, 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.

  With reference to FIG. 2, a power storage module constituting the power storage device will be described. The power storage module 12 illustrated in FIG. 2 includes a stacked body 30 in which a plurality of bipolar electrodes 32 are stacked. When viewed from the stacking direction of the bipolar electrode 32, the stacked body 30 has, for example, a rectangular shape. A separator 40 may be disposed between the adjacent bipolar electrodes 32.

  Each bipolar electrode 32 includes an electrode plate 34, a positive electrode 36 provided on the first surface 34 c of the electrode plate 34, and a negative electrode 38 provided on the second surface 34 d 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 across the separator 40, and the negative electrode 38 of one bipolar electrode 32 connects the separator 40. It faces the positive electrode 36 of the other bipolar electrode 32 that is adjacent in the stacking direction.

  In the stacking direction, an electrode plate 34 having a negative electrode 38 disposed on the inner surface (the lower surface in the drawing) is disposed at one end of the stacked body 30. The electrode plate 34 corresponds to a negative terminal electrode. In the stacking direction, an electrode plate 34 having a positive electrode 36 disposed on the inner surface (the upper surface in the drawing) is disposed at the other end of the stacked body 30. This electrode plate 34 corresponds to a positive terminal electrode. 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 cylindrical resin portion (seal member) 50 that extends in the stacking direction of the bipolar electrodes 32 and accommodates the stacked body 30. The resin part 50 holds the peripheral edge part 34 a of the plurality of electrode plates 34. The resin part 50 is configured to surround the laminated body 30. The resin portion 50 has, for example, a rectangular shape when viewed from the lamination direction of the bipolar electrode 32. That is, the resin part 50 is, for example, a rectangular tube shape.

  The resin part 50 is joined to the peripheral part 34a of the electrode plate 34, and the first seal part 52 that holds the peripheral part 34a and the first seal part 52 in the direction (X direction and Y direction) intersecting the stacking direction. 2nd seal part 54 provided in the outside. The second seal portion 54 is provided in a state of being sealed with the first seal portion 52.

  The first seal portion 52 constituting the inner wall of the resin portion 50 is provided over the entire circumference of the peripheral edge portion 34a of the electrode plate 34 in the plurality of bipolar electrodes 32 (that is, the stacked body 30). The first seal portion 52 is welded, for example, to the peripheral portion 34a of the electrode plate 34, and seals the peripheral portion 34a. That is, the first seal part 52 is joined to the peripheral edge part 34 a of the electrode plate 34. The peripheral edge 34 a of the electrode plate 34 of each bipolar electrode 32 is held in a state of being buried in the first seal portion 52. The peripheral portions 34 a of the electrode plates 34 disposed at both ends of the stacked body 30 are also held in a state of being buried in the first seal portion 52. As a result, an internal space V partitioned by the electrode plates 34 and 34 and the first seal portion 52 in an airtight and watertight manner is formed between the electrode plates 34 and 34 adjacent to each other in the stacking direction. 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 “volume of the internal space V” means the volume including the gap of the separator 40.

  The outer peripheral surface 52a of the first seal portion 52 is a heat-welded surface that is heat-welded. The second seal portion 54 constituting the outer wall of the resin portion 50 covers the outer peripheral surface 52 a of the first seal portion 52 extending in the stacking direction of the bipolar electrode 32. The inner peripheral surface 54a of the second seal portion 54 is welded, for example, to the outer peripheral surface 52a of the first seal portion 52, and seals the outer peripheral surface 52a. That is, the second seal portion 54 is joined to the outer peripheral surface 52 a of the first seal portion 52. The welding surface (joint surface) of the second seal portion 54 with respect to the first seal portion 52 forms, for example, four rectangular planes.

  The electrode plate 34 is a rectangular metal foil made of nickel, for example. The peripheral edge 34a of the electrode plate 34 is an uncoated region where the positive electrode active material and the negative electrode active material are not coated. In the uncoated region, the electrode plate 34 is exposed. The uncoated region is buried and held in the first seal portion 52 constituting the inner wall of the resin portion 50. 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 second surface 34 d of the electrode plate 34 may be slightly larger than the formation region of the positive electrode 36 on the first surface 34 c of the electrode plate 34.

  The separator 40 is formed in a sheet shape, for example. The separator 40 has a rectangular 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 resin portion 50 (the first seal portion 52 and the second seal portion 54) is formed in a rectangular cylindrical shape by, for example, injection molding using an insulating resin. Examples of the resin material constituting the resin portion 50 include polypropylene (PP), polyphenylene sulfide (PPS), and modified polyphenylene ether (modified PPE).

  In the power storage device 10, the positive electrode 36 on the first surface 34 c side of the electrode plate 34, the negative electrode 38 on the second surface 34 d side of the adjacent electrode plate 34, the separator 40 between the positive electrode 36 and the negative electrode 38, and the first surface A single cell is formed by the resin portion 50 that seals the space between the 34c and the second surface 34d. The resin part 50 regulates the movement of gas and electrolyte from one cell to another cell. Thereby, the insulation between adjacent cells is ensured.

  With reference to FIG. 3, the configuration of the first seal portion 52 will be described in more detail. The first seal portion 52 has a structure in which a plurality of frame bodies 60 are stacked in the stacking direction. The frame body 60 has a thickness larger than the thickness of the separator 40 in the stacking direction. More specifically, the frame body 60 has a thickness larger than the sum of the thickness of the electrode plate 34 and the thickness of the separator 40 in the stacking direction.

  The frame body 60 is bonded to the peripheral edge portion 34a of the electrode plate 34 of the bipolar electrode 32 and is bonded to another frame body 60 adjacent in the stacking direction. The bipolar electrode unit 65 is configured by the bipolar electrode 32 and the frame body 60 joined to the peripheral edge 34 a of the electrode plate 34 of the bipolar electrode 32. By joining the frame body 60 and another frame body 60, the frame body 60 defines the height of the internal space V (cell) formed between the electrode plates 34 adjacent to each other in the stacking direction. Yes.

  The frame 60 includes an inner peripheral portion 61 disposed on the first surface 34 c side of the electrode plate 34 and joined to the first surface 34 c, and an outer peripheral portion 62 provided continuously outside the inner peripheral portion 61. Including. Each of the inner peripheral portion 61 and the outer peripheral portion 62 corresponds to the shape of the electrode plate 34 and has, for example, a rectangular shape. The inner peripheral portion 61 is joined to the first surface 34c of the electrode plate 34 by welding, for example. That is, the inner peripheral part 61 is joined to the first surface 34 c of the electrode plate 34. An inner peripheral end 61 c (see FIG. 3) of the inner peripheral portion 61 corresponds to the inner peripheral end 52 c of the first seal portion 52. The thickness of the outer peripheral portion 62 is larger than the thickness of the inner peripheral portion 61 and is the thickness of the frame body 60. An outer peripheral surface (a peripheral end surface of the frame) 62d of the outer peripheral portion 62 corresponds to the outer peripheral end 52d (that is, the outer peripheral surface 52a) of the first seal portion 52.

  The frame 60 includes a first end surface 60a in the stacking direction and a second end surface 60b facing the first end surface 60a. The first end surface 60a of the frame body 60 is joined to the second end surface 60b of another frame body 60 adjacent in the stacking direction. The second end surface 60b of the frame body 60 is joined to the first end surface 60a of another frame body 60 adjacent in the stacking direction. The first end surface 60a and the second end surface 60b are joined to another frame body 60 in a planar shape in most of the circumferential direction (in the entire area excluding the communication port 70 described later). With this configuration, the frame body 60 defines the height of one cell in the power storage module 12. Between the inner peripheral part 61 and the outer peripheral part 62 having different thicknesses in the stacking direction, a rectangular annular step part 68 that connects them is formed. The depth of the stepped portion 68 in the stacking direction is larger than the thickness of the separator 40. In the stepped portion 68, a peripheral portion 40a including the outer peripheral end 40d of the separator 40 is disposed. That is, the stepped portion 68 formed in the frame body 60 faces the inside of the frame body 60, and provides a space for arranging the outer peripheral end 40 d of the separator 40 in the first seal portion 52. . For example, the peripheral edge portion 40a of the separator 40 is in contact with the surface 61a of the inner peripheral portion 61 (the surface opposite to that bonded to the first surface 34c). The separator 40 is within the height range of the frame body 60. A slight gap may be formed between the peripheral edge portion 40a and another electrode plate 34 adjacent to the separator 40 with the thickness of the negative electrode 38 therebetween.

  The outer peripheral end 40d of the separator 40 may be flush with the peripheral end surface 62d of the frame body 60. The outer peripheral end 40 d of the separator 40 may be located on the same side as or on the inner side of the outer peripheral end 52 d of the first seal portion 52 and on the outer side of the inner peripheral end 52 c of the first seal portion 52.

  With reference to FIG. 4, the structure of the resin part 50, the bipolar electrode 32, and the separator 40 is demonstrated. As shown in FIG. 4, when viewed from the stacking direction, the peripheral edge 40 a of the separator 40 overlaps the region where the first seal portion 52 is provided. In other words, when the separator 40 and the first seal portion 52 are projected on the plane perpendicular to the stacking direction (XY plane) in the stacking direction, these projected images overlap (ie, overlap). The separator 40 reaches the region where the first seal portion 52 is provided. The outer peripheral end 40 d of the separator 40 is located between the outer peripheral end 52 d and the inner peripheral end 52 c of the first seal portion 52. In FIG. 4, the separator 40 is partially broken so that the configuration of the first seal portion 52 can be easily understood.

  Even in the region near the first seal portion 52 of the electrode plate 34, the separator 40 is provided between the two adjacent electrode plates 34, so that the uncoated region of the adjacent electrode plates 34 does not directly face. In the two adjacent electrode plates 34, the separator 40 always exists between one uncoated region and the other uncoated region. The separator 40 provided so as to overlap the first seal portion 52 prevents two adjacent electrode plates 34 (particularly uncoated areas) from coming into contact with each other and causing a short circuit. The outer peripheral end 40 d may be located between the outer peripheral end 52 d and the inner peripheral end 52 c of the first seal portion 52 over the entire circumference of the separator 40. In a part in the circumferential direction of the separator 40, the outer peripheral end 40 d may be located between the outer peripheral end 52 d and the inner peripheral end 52 c of the first seal portion 52. In the circumferential direction of the separator 40, as the separator 40 overlaps the first seal portion 52 in a larger range, the occurrence of a short circuit can be prevented more reliably.

  As shown in FIG. 4, a communication port 70 penetrating the inside and outside of the frame body 60 is formed at one place in the circumferential direction between the frame bodies 60 adjacent in the stacking direction. Specifically, the communication port 70 passes through the first seal portion 52 in a direction orthogonal to the stacking direction. The communication port 70 is a place where the frame bodies 60 adjacent in the stacking direction are not partially joined. The communication port 70 can be used as a liquid injection port (electrolyte injection port) for injecting an electrolytic solution into the internal space V of the first seal portion 52. Further, the communication port 70 can be used as a pressure adjusting valve that opens and closes according to the internal pressure in the first seal portion 52 (for example, a gas venting safety valve that opens when the internal pressure exceeds a predetermined value). In this embodiment, the pressure adjustment unit 75 is provided so as to communicate with the communication port 70, and the pressure adjustment unit 75 assists or supplements the function of the communication port 70 as a pressure adjustment valve. The communication port 70 can be used as an electrolyte solution injection port and / or a pressure regulating valve.

  Hereinafter, the procedure for producing the power storage module 12 will be described with reference to FIGS.

  When the power storage module 12 is manufactured, first, a plurality of bipolar electrode units 65 are stacked via the separator 40 as a stacking step S1. At this time, the frame bodies 60 adjacent in the stacking direction are joined by welding or the like. In the stacking step S1, as shown in FIG. 6, the insert 80 for forming the communication port 70 described above is interposed between the frame bodies 60 adjacent in the stacking direction. At this time, the insert 80 is interposed so as to be orthogonal to the stacking direction and extend from the inside of the frame 60 to the outside of the frame. The insert 80 is, for example, a film member having a uniform width. The constituent material of the insert 80 may be a material having heat resistance to the extent that it has resistance to the processing temperature in the heat welding step S2 described later, and is a metal material as an example.

  The nests 80 are arranged between the frame bodies 60 adjacent to each other in the stacking direction. When the nesting 80 is arranged at the same position with respect to the circumferential direction of the frame body 60, there is a problem that only the thickness of the place where the nesting 80 is arranged becomes extremely thick compared to other places. The positions to be dispersed are distributed in the circumferential direction of the frame body 60. In the present embodiment, the positions where the nestings 80 are arranged are periodically dispersed in eight places in the circumferential direction of the frame body 60, and the nestings 80 overlap every eight layers as shown in the sectional view of FIG. ing.

  The plurality of nests 80 arranged at the same location in the circumferential direction of the frame body 60 are arranged so that the end portions 80a outside the frame do not overlap in the stacking direction. In the present embodiment, in the three nestings 80A to 80C arranged in order from the top in the stacking direction, the end portions 80a on the outer side of the frame are extended in the extending direction of the nesting 80 (that is, the direction crossing the frame 60). Left and right). Specifically, the positions of the end portions 80b inside the frames of the three nestings 80A to 80B are the same, but the lengths in the extending direction of the three nestings 80A to 80B are different from each other. The protruding length is different. More specifically, since the upper nesting 80A is shorter than the length of the nesting 80B in the middle, the protruding length of the nesting 80A is the shortest, and the lower nesting 80C is longer than the length of the nesting 80B in the middle. The projection length of the nesting 80C is the longest. That is, the protruding lengths of the three nestings 80A to 80C are sequentially increased toward the bottom.

  After the laminating step S1, as the thermal welding step S2, the outer peripheral surface 52a (seal end surface) of the first seal portion 52 configured by the peripheral end surfaces 62d of the frames 60 adjacent in the laminating direction is thermally welded. In this embodiment, since the 1st seal | sticker part 52 has the four outer peripheral surfaces 52a, a heat welding process is performed about each of the four outer peripheral surfaces 52a. In the outer peripheral surface 52a of the first seal portion 52, the inserts 80 protrude in a direction orthogonal to the outer peripheral surface 52a and are arranged in parallel.

  In heat welding process S2, it can carry out by applying the hot platen 85 of high temperature with respect to the outer peripheral surface 52a. The temperature of the hot plate 85 may be a temperature at which the frame body 60 melts, and is about 200 ° C. as an example. The material constituting the hot plate 85 is, for example, a metal material.

  As shown in FIG. 7, the hot plate 85 has a flat plate shape, and a through hole 86 is provided in a portion corresponding to the three inserts 80. The cross-sectional dimension of each through-hole 86 is designed to be slightly larger than the cross-sectional dimension of the insert 80 (the dimension in a cross section parallel to the outer peripheral surface 52a). By providing the through hole 86 in the heat plate 85, as shown in FIG. 8, when the heat plate 85 is applied to the outer peripheral surface 52a, the insert 80 is inserted through the through hole 86, and thus the insert 80 is obstructed. The heat plate 85 can be applied to the outer peripheral surface 52a without any problem.

  As shown in FIG. 8, by applying the hot plate 85 to the outer peripheral surface 52 a, the peripheral end surface 62 d and the outer peripheral portion 62 of the frame body 60 are melted to a certain depth, and the peripheral end surfaces 62 d of the adjacent frame bodies 60 are mutually connected. It becomes the welded heat-welded surface.

  In the heat welding step S2, each insert 80 may be heated. By heating the insert 80, the frame body 60 of the portion in contact with the insert 80 (for example, the portion P in FIG. 8 for the insert 80C) is melted. In order to insert the insert 80 into the through hole 86 of the hot plate 85, it is necessary to design the size of the communication port 70 larger than the size of the insert 80. Therefore, as shown in FIG. There may be a region where the hot plate 85 is not in contact with a part of 52a. In such a case, by heating the insert 80 and melting the frame body 60 in a portion in contact with the insert 80, the outer peripheral surface 52a of the region where the hot plate 85 does not contact (that is, the outer peripheral surface around the communication port 70). Can also be a heat-welded surface.

  After the heat welding step S2, as the communication port forming step S3, the communication port 70 is provided on the heat-welded outer peripheral surface 52a. Specifically, each insert 80 is removed from the first seal portion 52 to which the outer peripheral surface 52 a is thermally welded, and the portion from which the insert 80 is removed becomes the communication port 70. In this embodiment, an automatic machine (not shown) is used to remove the insert 80, and the gripper 90 of the automatic machine grips the end 80a outside the frame of the insert 80 as shown in FIG. More specifically, the gripper 90 has a pair of chucks 92 that can move in the thickness direction of the insert 80, and moves the pair of chucks 92 to thicken the end 80 a on the outside of the frame of the insert 80. Hold from the direction. In the present embodiment, the three nestings 80 are removed in the order of the lower nesting 80C, the middle nesting 80B, and the upper nesting 80A by the gripper 90 of the automatic machine. As described above, the protruding lengths of the three nestings 80A to 80B are sequentially increased toward the lower side. Therefore, the nestings 80 ( For example, a situation where the nest 80 (for example, the nest 80B) other than the nest 80C is contacted is avoided.

  As described above, according to the above-described power storage module 12 and the manufacturing method thereof, the plurality of frames constituting the first seal portion 52 (seal portion) by thermally welding the outer peripheral surface 52a (seal end surface). The relative positional deviation of 60 is suppressed. Therefore, when the communication port 70 is used as an electrolyte solution injection port or a gas venting safety valve, a situation in which those functions are impaired is effectively suppressed.

  When the communication port 70 is provided using the insert 80 described above, the size of the communication port 70 is substantially the same as the outer diameter size of the insert 80, so that the communication is achieved by adjusting the outer diameter size of the insert 80. The dimension of the mouth 70 can be easily adjusted. Further, the position of the communication port 70 can be easily adjusted by adjusting the position where the insert 80 is arranged in the circumferential direction of the frame body 60. Furthermore, the dimensional accuracy of the communication port 70 can be increased by increasing the dimensional accuracy of the insert 80.

  Work at the time of removing the inserts 80A, 80B, 80C in the communication port forming step S3 by preventing the end portions 80a on the frame outer sides of the inserts 80A, 80B, 80C from overlapping in the stacking direction as in the embodiment described above. Becomes easier. By removing the insert 80 using the gripper 90 of the automatic machine, automation in manufacturing the power storage module 12 can be promoted. As an aspect in which the end portions 80a outside the frames of the plurality of nestings 80 do not overlap in the stacking direction, the lengths in the extending direction of the plurality of nestings 80 are the same, and the positions of the end portions 80b inside the frames are the same. Even in a mode in which the protruding lengths are different from each other, the end portions 80a of the plurality of nests 80 do not overlap in the stacking direction. Further, as shown in FIG. 10, even in an aspect in which the plurality of nests 80 are arranged at different positions (frame body positions) with respect to the circumferential direction of the frame body 60, the end portions 80 a outside the frames of the plurality of nests 80 are arranged in the stacking direction. Do not overlap. In the case where the plurality of nestings 80 are arranged at different positions in the circumferential direction of the frame body 60, as shown in FIG. Does not overlap in the stacking direction. In the embodiment shown in FIG. 10 as well, the inserts 80 protrude in a direction orthogonal to the outer peripheral surface 52a and are arranged in parallel.

  In addition, the edge part 80a of the frame outer side of the some nest | insert 80 may overlap in the lamination direction. In the aspect shown in FIG. 11, the three inserts 80 are arranged at the same location in the circumferential direction of the frame body 60, and have the same protruding length that protrudes outward from the frame body 60. Are overlapped in the stacking direction. Thus, even if the edge part 80a on the frame outer side of the plurality of nestings 80 overlaps in the stacking direction, the nestings 80 can be removed manually by an operator, for example. In order to achieve automation, for example, as shown in FIG. 11, a through hole 81 may be provided that overlaps the end 80 a of each insert 80 </ b> D in the stacking direction. In this case, after the pin-like member 95 operated by the automatic machine is passed through all of the through holes 81, all the inserts 80D are removed simultaneously by moving the pin-like member 95 away from the outer peripheral surface 52a. be able to.

  As mentioned above, although embodiment of this invention was described, this invention is not limited to the said embodiment.

  For example, when the outer peripheral surface 52a of the first seal portion 52 is used as a heat welding surface, hot air or a laser may be used instead of the hot plate 85. Moreover, the outer peripheral surface 52a of the 1st seal | sticker part 52 can also be made into a heat welding surface by the combination of a hot plate, a hot air, a lamp | ramp (infrared lamp), induction heating, and a laser. The heating plate 85, hot air, lamp (infrared lamp), induction heating, laser, or the like can also be used for heating the insert 80.

  DESCRIPTION OF SYMBOLS 10 ... Power storage device, 12 ... Power storage module, 32 ... Bipolar electrode, 34 ... Electrode plate, 36 ... Positive electrode, 38 ... Negative electrode, 40 ... Separator, 50 ... Resin part, 52 ... First seal part, 52a ... Outer peripheral surface, 54 ... second seal part, 60 ... frame, 62 ... outer peripheral part, 62d ... peripheral end face, 65 ... bipolar electrode unit, 70 ... communication port, 75 ... pressure adjusting unit, 80, 80A, 80B, 80C, 80D ... nested, 80a, 80b ... end, 81 ... through hole, 85 ... hot plate, 86 ... through hole, V ... internal space.

Claims (11)

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 stacked via a separator;
A structure that extends in the stacking direction of the stacked body so as to accommodate the stacked body and that is joined to a peripheral portion of each electrode plate of the plurality of bipolar electrodes is overlapped in the stacking direction of the stacked body. A power storage module comprising a sealing member having a cylindrical sealing portion,
The seal end surface of the seal portion configured by the peripheral end surfaces of the frame bodies adjacent in the stacking direction of the laminate is a heat welding surface,
The electrical storage module in which the communicating port which penetrates the said seal part in the direction orthogonal to the said lamination direction between the frame bodies adjacent in the said lamination direction is provided in the seal end surface of the said seal part.   The power storage module according to claim 1, wherein the communication port is a liquid injection port for injecting an electrolyte into the seal portion.   The power storage module according to claim 1 or 2, wherein the communication port is a pressure regulating valve that opens and closes according to an internal pressure in the seal portion. 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 stacked via a separator;
A structure that extends in the stacking direction of the stacked body so as to accommodate the stacked body and that is joined to a peripheral portion of each electrode plate of the plurality of bipolar electrodes is overlapped in the stacking direction of the stacked body. And a sealing member having a cylindrical sealing portion that is made,
A laminating step of laminating a plurality of bipolar electrode units in which the frame body is bonded to a peripheral portion of each electrode plate of the plurality of bipolar electrodes via the separator;
A heat welding step of heat-welding a seal end face constituted by a peripheral end face of a frame body adjacent in the stacking direction of the laminate;
And a communication port forming step of providing a communication port penetrating the seal portion in a direction orthogonal to the stacking direction between the frames adjacent to each other in the stacking direction on the heat-sealed end surface of the seal. . In the laminating step, the plurality of bipolar electrode units are laminated by interposing a nesting extending from the inside of the frame to the outside of the frame between adjacent frames in the laminating direction,
In the thermal welding step, the seal end face of the seal portion is thermally welded with the insert interposed therebetween,
5. The method for manufacturing an energy storage module according to claim 4, wherein, in the communication port forming step, the insert is removed from a seal portion to which the seal end face is thermally welded. In the stacking step, the plurality of bipolar electrode units are stacked by interposing a plurality of the inserts between different frames of the plurality of bipolar electrode units,
The manufacturing method of the electrical storage module according to claim 5, wherein end portions on the outer side of the plurality of nested frames do not overlap in a stacking direction of the stacked body.   In the stacking step, the plurality of nests are interposed so as to protrude from the same frame body position to the outside of the frame in the stacking direction of the stacked body, and to protrude differently from the frame body in the frame outward direction. 6. A method for producing the power storage module according to 6.   The method for manufacturing a power storage module according to claim 6, wherein, in the stacking step, the plurality of nests are interposed so as to protrude out of the frame from different frame positions with respect to the circumferential direction of the frame. In the stacking step, the plurality of bipolar electrode units are stacked by interposing a plurality of the inserts between different frames of the plurality of bipolar electrode units,
The ends outside the frames of the plurality of nestings overlap with each other in the stacking direction of the stacked body, and through holes are provided at the ends of the plurality of nestings in the stacking direction of the stacked body. 6. A method for producing the electricity storage module according to 5.   The said heat welding process WHEREIN: The said frame body of the part which contact | connects this nest is heated by heating the said nest | insert, and the said seal end surface around the said communication port is heat-welded. The manufacturing method of the electrical storage module of description.   The manufacturing method of the electrical storage module as described in any one of Claims 4-10 which uses a hot plate, a hot air, or a laser for the heat welding of the said seal end surface in the said heat welding process.

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