JP2019160728A - Power storage device - Google Patents

Abstract

To reduce the number of parts of a power storage device.SOLUTION: A power storage device 1 includes an outer lid 11 (first resin body) forming a part of an exterior body 10, a bus bar 81 (conductive member) accommodated in the exterior body 10, an external terminal 91 joined to the bus bar 81 and exposed from the outer lid 11, and a resin member 15 (second resin body) fixed to the external terminal 91, and the resin member 15 is joined to the outer lid 11 over the entire circumference of the external terminal 91 in a state where the resin member 15 overlaps the outer lid 11.SELECTED DRAWING: Figure 4

Description

  The present invention relates to a power storage device including a power storage element and an exterior body that houses the power storage element.

  Conventionally, a power storage device is known in which a bus bar electrically connected to a power storage element in an exterior body and an external terminal connected to the bus bar are insert-molded with respect to the exterior body (see, for example, Patent Document 1). . In such a power storage device, a bus bar electrically connected to an external terminal and insert-molded in the exterior body and another bus bar accommodated in the exterior body are fastened with a fastening member, and then the periphery is covered. Airtightness is secured by covering with a member.

JP 2017-130289 A

  As described above, the power storage device includes the insert-shaped bus bar, the fastening member, and the lid member. However, these increase the number of parts of the power storage device.

  For this reason, an object of this invention is to provide the electrical storage apparatus which can reduce a number of parts.

  In order to achieve the above object, a power storage device according to one embodiment of the present invention includes a first resin body that forms part of an exterior body, a conductive member housed in the exterior body, An external terminal exposed from the one resin body; and a second resin body fixed to the external terminal, the second resin body overlapping the first resin body, the first resin body over the entire circumference of the external terminal It is joined to.

  According to this, since the second resin body fixed to the external terminal is joined to the first resin body in a state of being overlapped with the first resin body forming a part of the exterior body, the airtightness around the first resin body Is secured. Moreover, the conductive member accommodated in the exterior body is directly joined to the external terminal.

  That is, in the case of the prior art, a bus bar (conductive member) insert-molded in the exterior body, a fastening member that joins the bus bars, and the like are required, but these are unnecessary in the power storage device according to this aspect. . Therefore, the number of parts can be reduced.

  The second resin body is disposed outside the first resin body.

  According to this, since the second resin body is disposed outside the first resin body, at the time of assembly, the external terminal fixed to the second resin body is the first part which is a part of the exterior body. The conductive member can be joined from the outside of the resin body. Accordingly, the external terminal and the conductive member can be easily joined from the outside of the exterior body.

  The second resin body and the external terminal are insert molded bodies.

  According to this, since the second resin body and the external terminal are insert molded bodies, the airtightness between the second resin body and the external terminal can be reliably maintained without performing an airtight treatment. As a result, a member (for example, a lid member, O-ring) or the like for improving airtightness is not necessary, and the number of components can be reduced.

  The second resin body is made of a light transmissive resin.

  According to this, since the second resin body is a light transmissive resin, for example, even if laser light is irradiated, the second resin body can be transmitted and reach the member overlapping the second resin body. . Thereby, the said member can be heated with a laser beam. That is, it is possible to weld the second resin body and the member by laser welding or the like. Laser welding is a joining method that enables highly airtight joining. For this reason, the member for improving airtightness becomes unnecessary, and the number of parts can be reduced.

  The second resin body and the external terminal are provided with a first joint for joining the second resin body and the external terminal over the entire circumference of the external terminal, and the second resin body and the first resin body. Are provided with a second joint for joining the second resin body and the first resin body over the entire circumference of the external terminal.

  According to this, since the 2nd resin body and the 1st resin body are joined over the perimeter of the external terminal by the 2nd junction part, the airtightness between the 2nd resin body and the 1st resin body is made. Can be secured. Moreover, since the 2nd resin body and the external terminal are joined over the perimeter of the external terminal by the 1st junction part, the airtightness between a 2nd resin body and an external terminal is securable. That is, even if the second resin body and the external terminal are not fixed before assembly of the power storage device, the airtightness between the second resin body and the external terminal can be ensured after assembly. In addition, a member for improving airtightness is not necessary, and the number of parts can be reduced.

  According to the power storage device of the present invention, the number of parts can be reduced.

FIG. 1 is a perspective view illustrating an appearance of a power storage device according to an embodiment. FIG. 2 is an exploded perspective view showing each component when the power storage device according to the embodiment is disassembled. FIG. 3 is a perspective view illustrating a schematic configuration of the outer lid according to the embodiment. FIG. 4 is a cross-sectional view showing the structure around the external terminal according to the embodiment. FIG. 5 is a top view showing a structure around the external terminal according to the embodiment. FIG. 6 is a cross-sectional view showing one step of the method of assembling the external terminal and the outer lid according to the embodiment. FIG. 7 is a cross-sectional view showing one step in the method of assembling the external terminal and the outer lid according to the embodiment. FIG. 8 is a cross-sectional view illustrating a state before the outer lid and the external terminal according to Modification 1 are assembled. FIG. 9 is a cross-sectional view illustrating a state before the outer lid and the external terminal according to Modification 2 are assembled. FIG. 10 is a cross-sectional view illustrating a state after the outer lid and the external terminal according to Modification 2 are assembled. FIG. 11 is a cross-sectional view illustrating a state after the outer lid and the external terminal according to the third modification are assembled.

  Hereinafter, a power storage device according to an embodiment of the present invention and modifications thereof will be described with reference to the drawings. It should be noted that each of the embodiments and modifications thereof described below is a comprehensive or specific example. Numerical values, shapes, materials, constituent elements, arrangement positions and connection forms of constituent elements, and the like shown in the following embodiments and modifications thereof are merely examples, and are not intended to limit the present invention. In addition, among the constituent elements in the following embodiments and modifications thereof, constituent elements that are not described in the independent claims indicating the highest concept are described as arbitrary constituent elements. In each drawing, dimensions and the like are not strictly illustrated.

  In the following description and drawings, the direction in which the power storage elements are arranged, the direction in which the long side surfaces of the containers of the power storage elements are opposed, or the thickness direction of the containers is defined as the X-axis direction. In addition, the direction in which the electrode terminals are arranged in one power storage element or the facing direction of the short side surface of the container of the power storage element is defined as the Y-axis direction. In addition, an alignment direction of the main body portion and the outer lid, an alignment direction of the energy storage element, the bus bar, and the substrate, or a vertical direction in the exterior body of the power storage device is defined as a Z-axis direction. These X-axis direction, Y-axis direction, and Z-axis direction are directions that intersect with each other (hereinafter, orthogonal in the embodiment and its modifications). Although the case where the Z-axis direction does not become the vertical direction may be considered depending on the usage mode, the Z-axis direction will be described below as the vertical direction for convenience of explanation. In the following description, for example, the X axis direction plus side indicates the arrow direction side of the X axis, and the X axis direction minus side indicates the opposite side to the X axis direction plus side. The same applies to the Y-axis direction and the Z-axis direction.

[General description of power storage device]
First, a general description of the power storage device 1 according to the embodiment will be described with reference to FIGS. 1 and 2. FIG. 1 is a perspective view showing an external appearance of a power storage device 1 according to the embodiment. FIG. 2 is an exploded perspective view showing each component when the power storage device 1 according to the embodiment is disassembled.

  The power storage device 1 is a device that can charge electricity from the outside and discharge electricity to the outside. For example, the power storage device 1 is a battery module used for power storage use or power supply use. Specifically, the power storage device 1 is, for example, an automobile such as an electric vehicle (EV), a hybrid electric vehicle (HEV), or a plug-in hybrid electric vehicle (PHEV), a motorcycle, a watercraft, a snowmobile, an agricultural machine, a construction It is used as a battery for driving a moving body such as a machine or starting an engine.

  As shown in FIGS. 1 and 2, the power storage device 1 includes a power storage element 20 and an exterior body 10 that houses the power storage element 20. In the present embodiment, eight power storage elements 20 are accommodated in the outer package 10. The exterior body 10 includes a main body 12 that houses a plurality of power storage elements 20 and a bus bar plate 17 that is disposed above the plurality of power storage elements 20. In the present embodiment, the exterior body 10 further includes an outer lid 11 disposed so as to cover the top of the bus bar plate 17. In addition to the plurality of power storage elements 20, a plurality of bus bars 33 held on the bus bar plate 17, bus bar covers 60 and 70, and a connection unit 80 including a control circuit and the like are accommodated inside the exterior body 10. .

  The exterior body 10 is a rectangular (box-shaped) container (module case) that constitutes the exterior body of the power storage device 1. That is, the exterior body 10 is a member that fixes the plurality of power storage elements 20, the bus bar plate 17 and the like at predetermined positions and protects these elements from impacts and the like.

  The outer lid 11 included in the exterior body 10 is a rectangular member that closes the opening of the main body 12, and includes an external terminal 91 on the positive electrode side and an external terminal 92 on the negative electrode side. The external terminals 91 and 92 are electrically connected to the plurality of power storage elements 20 via the connection unit 80 and the bus bar 33, and the power storage device 1 receives electricity from the outside via the external terminals 91 and 92. Charge and discharge electricity to the outside. The external terminals 91 and 92 are made of, for example, a metal conductive member such as a copper alloy such as brass, copper, aluminum, or an aluminum alloy. The main body 12 is a bottomed rectangular cylindrical housing (housing) in which an opening is formed, and houses the power storage element 20 and the like.

  Moreover, the main body 12 and the outer lid 11 of the outer package 10 are made of, for example, polypropylene (PP), polyethylene (PE), polycarbonate (PC), polyphenylene sulfide resin (PPS), polyetheretherketone (PEEK), tetrafluoroethylene. -It comprises an insulating material such as perfluoroalkyl vinyl ether (PFA), polytetrafluoroethylene (PTFE), polybutylene terephthalate (PBT), or poly ether sulfone (PES). Thus, the outer package 10 avoids the storage element 20 and the like from coming into contact with an external metal member or the like. In the exterior body 10, at least the outer lid 11 is formed from a light-absorbing resin. The light absorbing resin is a resin containing a laser absorbing dye. The laser-absorbing dye includes at least one of a pigment-based absorbing dye and a dye-based absorbing dye. An example of the pigment-based absorbing dye is carbon black.

  The storage element 20 is a secondary battery (unit cell) that can charge and discharge electricity, and more specifically, a non-aqueous electrolyte secondary battery such as a lithium ion secondary battery. . The power storage element 20 has a flat rectangular parallelepiped shape (square shape), and in this embodiment, eight power storage elements 20 are arranged in the X-axis direction. In addition, the shape of the electrical storage element 20 and the number of the electrical storage elements 20 arranged are not limited. The storage element 20 is not limited to a non-aqueous electrolyte secondary battery, and may be a secondary battery other than a non-aqueous electrolyte secondary battery, a capacitor, or a user charged by a battery. The battery may be a primary battery that can use the stored electricity without having to perform the operation. Further, the electricity storage element 20 may be a battery using a solid electrolyte. Moreover, the shape of the electrical storage element 20 is not limited to a square shape, and may be a cylindrical shape, a long cylindrical shape, or a polygonal column shape other than a rectangular parallelepiped.

  Specifically, the electricity storage element 20 includes a metal container 21, and a metal electrode terminal 22 (a positive electrode terminal and a negative electrode terminal) is provided on the lid portion of the container 21. The electrode terminal 22 (positive electrode terminal and negative electrode terminal) is an electrode terminal arranged so as to protrude from the lid portion of the container 21 toward the bus bar plate 17 (upward, that is, toward the plus side in the Z-axis direction). The electrode terminal 22 is connected to the external terminals 91 and 92 via at least one bus bar 33 and the connection unit 80, whereby the power storage device 1 charges electricity from the outside and discharges electricity to the outside. be able to. The lid portion of the container 21 may be provided with a liquid injection part for injecting an electrolytic solution, a gas discharge valve for discharging gas and releasing the pressure when the pressure in the container 21 increases. In addition, an electrode body (also referred to as a power storage element or a power generation element), a current collector (a positive electrode current collector and a negative electrode current collector), and the like are disposed inside the container 21, and an electrolytic solution (non-aqueous electrolyte) or the like is provided. Although it is enclosed, detailed description is omitted.

  The bus bar 33 is a rectangular plate-like member that is disposed on the at least two power storage elements 20 while being held by the bus bar plate 17 and electrically connects the electrode terminals 22 of the at least two power storage elements 20. is there. The bus bar 33 is formed of a conductive member made of metal such as copper, copper alloy, aluminum, or aluminum alloy, for example. In the present embodiment, two sets of power storage elements 20 are connected in parallel using five bus bars 33 to form four sets of power storage element groups, and the four sets of power storage element groups are connected in series. Connected.

  The connection unit 80 is a unit having a plurality of bus bars, a control board, and the like, and connects a power storage element group including eight power storage elements 20 to the external terminals 91 and 92. The control board included in the connection unit 80 has a plurality of electrical components, and a detection circuit for detecting the state of each storage element 20 and a control circuit for controlling charging and discharging are formed by the plurality of electrical components. Yes. In the present embodiment, the connection unit 80 is fixed to the bus bar plate 17. Note that the detection circuit and the control circuit may be formed on separate substrates. Moreover, the connection unit 80 does not need to have a control board. In this case, for example, a control device arranged outside the power storage device 1 may control charging and discharging of each power storage element 20.

  The bus bar plate 17 is an example of a holding member that is arranged above the plurality of power storage elements 20 (on the side where the electrode terminals 22 are arranged). In the present embodiment, the bus bar plate 17 is a member that holds the bus bar 33. More specifically, the bus bar plate 17 is a member that holds the plurality of bus bars 33, the connection unit 80, and other wirings (not shown), and can regulate the positions of these members. In addition, the bus bar plate 17 is provided with a plurality of bus bar openings 17 a that hold each of the plurality of bus bars 33 and expose a part of each of the plurality of bus bars 33 to the plurality of power storage elements 20. . In addition, the bus bar plate 17 has a role of regulating, for example, the upward movement (plus Z-axis direction) of the plurality of power storage elements 20 by being fixed to the main body 12 by a method described later.

  The bus bar plate 17 disposed above the plurality of power storage elements 20 may be called, for example, a “bus bar frame” or an “inner lid”. The bus bar plate 17 is made of an insulating material such as PP, PE, PC, PPS, PEEK, PFA, PTFE, PBT, or PES.

  Each of the bus bar covers 60 and 70 is a resin member that covers the plurality of bus bars 33 from above. For example, the bus bar covers 60 and 70 have a role of electrically insulating the plurality of bus bars 33 and the connection unit 80.

[Structure around external terminals]
Next, the structure around the external terminals 91 and 92 will be described. FIG. 3 is a perspective view showing a schematic configuration of the outer lid 11 according to the embodiment.

  As shown in FIG. 3, the external terminals 91 and 92 are joined to the bus bars 81 and 82 of the connection unit 80 while being attached to the outer lid 11. The outer lid 11 is an example of a first resin body that forms part of the exterior body 10. The outer lid 11 is made of an insulating material such as PP, PE, PC, PPS, PEEK, PFA, PTFE, PBT, or PES. The bus bars 81 and 82 are an example of a conductive member housed in the exterior body 10 and are electrically connected to the power storage element group. The bus bars 81 and 82 are joined to the external terminals 91 and 92 by fastening with screws 83 and 84. Note that any joining method may be employed for joining the bus bars 81 and 82 and the external terminals 91 and 92. Examples of joining methods other than fastening with screws 83 and 84 include caulking, welding, adhesion, and brazing.

  Hereinafter, the structure around the external terminal 91 will be described in detail. Since the structure around the external terminal 92 is substantially the same, the description thereof is omitted here.

  FIG. 4 is a cross-sectional view showing a structure around the external terminal 91 according to the embodiment. FIG. 5 is a top view showing a structure around the external terminal 91 according to the embodiment.

  The outer lid 11 is provided with an annular terminal attaching portion 111 to which the external terminal 91 is attached. The terminal attachment portion 111 is formed in a cylindrical shape and protrudes from the upper surface and the lower surface of the outer lid 11. The external terminal 91 is attached to the through hole 112 of the terminal attachment portion 111 so as to be embedded.

  The external terminal 91 is made of a conductive material such as brass or aluminum. The external terminal 91 is integrally provided with a connection portion 911 to which an external device is electrically connected and a pedestal portion 912 that holds the connection portion 911.

  The connection part 911 is formed in a substantially truncated cone shape and protrudes from the terminal attachment part 111 of the outer lid 11. The pedestal portion 912 is formed in a columnar shape, and a connection portion 911 is provided on the upper surface thereof. The pedestal portion 912 and the connection portion 911 have their respective central axes aligned on the same axis. A screw hole 913 that engages with the screw 83 is formed on the bottom surface of the base portion 912. The screw hole 913 is formed so that its central axis overlaps the central axis of the connecting portion 911.

  A resin member 15 that is an example of a second resin body is fixed to the external terminal 91. Specifically, the resin member 15 is an annular plate member, and is formed of, for example, a light transmissive resin. Here, the light transmittance of the light transmissive resin is preferably 10% or more. Examples of the light transmissive resin include silicone resin, silicone-modified resin, epoxy resin, phenol resin, polycarbonate resin, acrylic resin, polymethylpentene resin, polynorbornene resin, thermosetting resin, or one of these resins. The hybrid resin etc. which are contained above are mentioned. Examples of the thermosetting resin as the light transmissive resin include ASA, ABS, PA, ASN, PS, PC, PES, PE, PP, POM, PBT, PA6, and PA66.

  The resin member 15 is integrally assembled with the external terminal 91 so as to be in close contact with the upper surface of the base portion 912 and in close contact with the outer peripheral surface of the proximal end portion of the connection portion 911. Specifically, the resin member 15 and the external terminal 91 are insert molded bodies that are integrally molded by insert molding. The outer peripheral edge of the resin member 15 protrudes outward from the outer peripheral edge of the pedestal portion 912 over the entire periphery, and overlaps the upper surface of the terminal attachment portion 111 of the outer lid 11. The resin member 15 is joined to the terminal mounting portion 111 over the entire circumference of the external terminal 91. For this reason, the resin member 15 and the outer lid 11 are provided with a joint portion 16 that joins the resin member 15 and the outer lid 11 over the entire circumference of the external terminal 91. In FIG. 5, a boundary portion between the pedestal portion 912 of the external terminal 91 and the terminal attachment portion 111 of the outer lid 11 is illustrated by a broken line, and an installation location of the joint portion 16 is illustrated by a two-dot chain line.

  As shown in FIG. 4, the bus bar 81 is a conductive plate-like member made of a conductive material such as copper, and has a through hole 811 at one end thereof. The bus bar 81 is assembled to the external terminal 91 by inserting the screw 83 through the through hole 811 and fastening the screw 83 to the screw hole 913 of the external terminal 91.

[Assembly method of external terminal and outer lid]
Next, a method for assembling the external terminal 91 and the outer lid 11 will be described. 6 and 7 are cross-sectional views illustrating one process of the assembly method of the external terminal 91 and the outer lid 11 according to the embodiment. Specifically, FIG. 6 and FIG. 7 correspond to FIG. Prior to assembly, the upper surface of the terminal mounting portion 111 is a flat surface as a whole.

  First, as shown in FIG. 6, the external terminal 91 and the resin member 15 integrated by insert molding are inserted into the through hole 112 of the terminal mounting portion 111 of the outer lid 11. At the time of insertion, the bus bar 81 is attached to the external terminal 91 by screwing the screw hole 913 of the external terminal 91 to the screw 83 attached to the bus bar 81. After the screwing, the resin member 15 overlaps the upper surface of the terminal mounting portion 111.

  Next, the resin member 15 and the external terminal 91 are joined by a laser transmission welding method. Specifically, as shown in FIG. 7, the laser beam is applied to the overlapping region between the resin member 15 and the terminal mounting portion 111. In FIG. 7, the laser beam is indicated by an arrow Y1. The laser beam is applied to the overlapping region over the entire circumference of the external terminal 91. As described above, since the resin member 15 is formed from a light-transmitting resin and the outer lid 11 is formed from a light-absorbing resin, the laser light passes through the resin member 15, but the outer lid 11. Absorbed in. For this reason, heat is generated at the boundary surface between the outer lid 11 and the resin member 15, and the resin member 15 and the outer lid 11 are welded. As a result, since the joint portion 16 is formed over the entire circumference of the external terminal 91, the airtightness of the boundary portion between the resin member 15 and the outer lid 11 is ensured.

[Effects, etc.]
As described above, according to the power storage device 1 according to the present embodiment, the outer lid 11 (first resin body) that forms part of the exterior body 10 and the bus bar 81 (conductive member) accommodated in the exterior body 10. And an external terminal 91 that is joined to the bus bar 81 and exposed from the outer lid 11, and a resin member 15 (second resin body) that is fixed to the external terminal 91, and the resin member 15 overlaps the outer lid 11. In this state, it is joined to the outer lid 11 over the entire circumference of the external terminal 91.

  According to this, since the resin member 15 fixed to the external terminal 91 is joined to the outer lid 11 in a state of being overlapped with the outer lid 11 forming a part of the exterior body 10, the surrounding airtightness is reduced. It is secured. Further, the bus bar 81 accommodated in the exterior body 10 is directly bonded to the external terminal 91.

  That is, in the case of the prior art, a bus bar insert-molded in the exterior body, a fastening member that joins the bus bar and the bus bar accommodated in the exterior body, and the like are necessary. In the apparatus 1, these are unnecessary. Moreover, if the fastening member which joins bus bars becomes unnecessary, the cover member which covers the circumference | surroundings will also become unnecessary. As a result, the number of parts can be reduced.

  Further, the resin member 15 is disposed outside the outer lid 11.

  According to this, since the resin member 15 is disposed outside the outer lid 11, the external terminal 91 fixed to the resin member 15 is joined to the bus bar 81 from the outside of the outer lid 11 during assembly. be able to. Thereby, the external terminal 91 and the bus bar 81 can be easily joined from the outside of the exterior body 10.

  The resin member 15 and the external terminal 91 are insert molded bodies.

  According to this, since the resin member 15 and the external terminal 91 are insert molded bodies, the airtightness between the resin member 15 and the external terminal 91 can be reliably maintained without performing an airtight process. As a result, a member (for example, a lid member, O-ring) or the like for improving airtightness is not necessary, and the number of components can be reduced.

  The resin member 15 is made of a light transmissive resin.

  According to this, since the resin member 15 is a light-transmitting resin, for example, a member that passes through the resin member 15 and overlaps the resin member 15 even when laser light is irradiated (the outer lid 11 in the present embodiment). Can be reached. Thereby, the outer lid | cover 11 can be heated with a laser beam. That is, the resin member 15 and the outer lid 11 can be welded by laser welding or the like. Laser welding is a joining method that enables highly airtight joining. For this reason, the member for improving airtightness becomes unnecessary, and the number of parts can be reduced.

[Modification 1]
In the said embodiment, before the assembly of the external terminal 91 and the outer cover 11, the case where the upper surface of the terminal attachment part 111 became a flat surface as a whole was illustrated. However, before assembly, the upper surface of the terminal mounting portion may not be a flat surface. FIG. 8 is a cross-sectional view illustrating a state before the outer lid 11a and the external terminal 91 according to Modification 1 are assembled. Specifically, FIG. 8 corresponds to FIG. In the following description, the same parts as those in the above embodiment may be denoted by the same reference numerals and the description thereof may be omitted.

  As shown in FIG. 8, the outer lid 11a according to the first modification is provided with a rib 118 protruding upward from the upper surface of the terminal mounting portion 111a. The rib 118 is provided continuously over the entire circumference of the terminal mounting portion 111a. In the first modification, the rib 118 having a triangular shape in cross section is illustrated, but the rib may have any shape. The rib 118 is provided in a portion corresponding to the joint portion 16, that is, a portion irradiated with a laser. Thereby, the rib 118 becomes a part (melting allowance) which melts at the time of joining by the laser transmission welding method, and parts other than the rib 118 are hardly melted. For this reason, resin burrs are less likely to appear. Resin burrs cause appearance defects and foreign matter dust. However, since the formation of resin burrs can be suppressed by providing the ribs 118, appearance defects and foreign matter dust can also be suppressed. A rib protruding downward from the lower surface of the resin member 15 may be provided.

[Modification 2]
In the said embodiment, the case where the resin member 15 and the external terminal 91 were the insert molded object integrated by insert molding was illustrated. However, the resin member and the external terminal may be separate. FIG. 9 is a cross-sectional view illustrating a state before the outer lid 11b and the external terminal 91b according to the second modification are assembled. FIG. 10 is a cross-sectional view illustrating a state after the outer lid 11b and the external terminal 91b according to the second modification are assembled. Specifically, FIG. 9 is a diagram corresponding to FIG. 6, and FIG. 10 is a diagram corresponding to FIG.

  As shown in FIG. 9, before being attached to the outer lid 11, the resin member 15b is separated from the external terminal 91b. From this state, the external terminal 91b is inserted into the through hole 112 of the terminal attachment portion 111b of the outer lid 11. At the time of insertion, the bus bar 81 is attached to the external terminal 91b by screwing the screw hole 913 of the external terminal 91b into the screw 83 attached to the bus bar 81.

  Thereafter, the connecting portion 911 of the external terminal 91b is inserted into the through hole of the annular resin member 15b. At this time, the resin member 15 b is overlapped with the upper surface of the terminal mounting portion 111.

  Next, the resin member 15b and the external terminal 91b are joined by a laser transmission welding method, and the resin member 15b and the outer lid 11 are joined by a laser transmission welding method. Specifically, as shown in FIG. 10, the laser beam is applied to the overlapping region between the resin member 15b and the base portion 912b of the external terminal 91b. The laser beam is applied to the overlapping region over the entire circumference of the external terminal 91b. As described above, since the resin member 15b is formed of a light-transmitting resin and the external terminal 91b is formed of metal, the laser light is transmitted through the resin member 15b but is absorbed by the external terminal 91b. The Therefore, heat is generated at the boundary surface between the resin member 15b and the external terminal 91b, and the resin member 15b and the external terminal 91b are welded. Thereby, the 1st junction part 161 which joins the resin member 15b and the external terminal 91b is provided in the resin member 15b and the external terminal 91b. Since this 1st junction part 161 is formed over the perimeter of the external terminal 91b, the airtightness of the boundary part of the resin member 15b and the external terminal 91b is securable.

  Moreover, the resin member 15b and the terminal attachment part 111b are welded by irradiating a laser beam with respect to the overlapping region of the resin member 15b and the terminal attachment part 111b. Thereby, the 2nd junction part 162 which joins the resin member 15b and the outer cover 11b over the perimeter of the said external terminal 91b is provided in the resin member 15b and the outer cover 11b. The first joint 161 and the second joint 162 are double concentric circles in which the first joint 161 is disposed on the inner side of the second joint 162.

  As described above, according to the second modification, the resin member 15b and the external terminal 91b are provided with the first joint 161 that joins the resin member 15b and the external terminal 91b over the entire circumference of the external terminal 91b. The resin member 15b and the outer lid 11b are provided with a second joint 162 that joins the resin member 15b and the outer lid 11 over the entire circumference of the external terminal 91b. The first joint 161 is provided inside the second joint 162 with reference to the center of the external terminal 91b.

  According to this, since the resin member 15b and the outer lid 11b are joined over the entire circumference of the external terminal 91b by the second joining portion 162, airtightness between the resin member 15b and the outer lid 11b is ensured. be able to. Moreover, since the resin member 15b and the external terminal 91b are joined over the entire circumference of the external terminal 91b by the first joint portion 161, airtightness between the resin member 15b and the external terminal 91b can be ensured. . That is, even if the resin member 15b and the external terminal 91b are not fixed before the power storage device 1 is assembled, the airtightness between the resin member 15b and the external terminal 91b can be ensured after the assembly. In addition, a member for improving airtightness is not necessary, and the number of parts can be reduced.

[Modification 3]
In the said embodiment, the case where the resin member 15 was arrange | positioned on the outer side of the outer cover 11 was illustrated. However, the resin member may be disposed inside the outer lid. FIG. 11 is a cross-sectional view illustrating a state after the outer lid 11c and the external terminal 91c according to the third modification are assembled. Specifically, FIG. 11 corresponds to FIG.

  As shown in FIG. 11, the resin member 15c and the external terminal 91c are insert molded bodies. Specifically, the resin member 15c is integrated with the bottom surface of the base portion 912c of the external terminal 91c. For this reason, the airtightness between the resin member 15c and the external terminal 91c is ensured. The outer peripheral edge of the resin member 15c protrudes outward from the outer peripheral edge of the pedestal portion 912c over the entire periphery, and overlaps the lower surface of the terminal attachment portion 111c of the outer lid 11c. The resin member 15c is joined to the terminal attachment portion 111c over the entire circumference of the external terminal 91c. For this reason, the resin member 15c and the outer lid 11c are provided with a joining portion 16c for joining the resin member 15c and the outer lid 11c over the entire circumference of the external terminal 91c by a laser transmission welding method. The joint 16c ensures airtightness between the resin member 15c and the outer lid 11c.

  The resin member 15c and the external terminal 91c do not have to be an insert molded body. In this case, the resin member 15c and the external terminal 91c are provided with a joint for joining the resin member 15c and the external terminal 91c over the entire circumference of the external terminal 91c by the laser transmission welding method. Thereby, the airtightness between the resin member 15c and the external terminal 91c can be ensured.

  In this case, it is preferable to form the joint portion 16c before joining the outer lid 11c and the main body portion 12 together. Specifically, as shown by an arrow Y1 in FIG. 7, the laser beam is irradiated from the plus side in the Z-axis direction to the overlapping region between the resin member 15 and the terminal mounting portion 111. In FIG. Laser light can be applied to the overlapping region between the resin member 15c and the terminal mounting portion 111c from the minus side of the direction. In this manner, after the resin member 15c and the external terminal 91c are joined, the outer lid 11c and the main body 12 can be joined.

  Further, when the resin member 15 is disposed outside the outer lids 11, 11a, 11b like the outer lids 11, 11a, 11b of the above-described embodiments, the outer lids 11, 11a, 11b, the main body part 12, Regardless of before and after joining, the resin members 15 and 15b and the external terminals 91 and 91b can be joined even after the outer lids 11, 11a, 11b and the main body 12 are joined.

[Others]
Although the power storage device according to the embodiment of the present invention has been described above, the present invention is not limited to the above-described embodiment and modification examples. That is, it should be considered that the embodiment and the modification disclosed this time are examples in all respects and are not restrictive. The scope of the present invention is defined by the terms of the claims, rather than the description above, and is intended to include any modifications within the scope and meaning equivalent to the terms of the claims.

  For example, in the above embodiment, the case where the external terminals 91 and 92 protrude from the outer lid 11 is illustrated. However, the external terminal may be exposed even if it does not protrude from the outer lid. That is, the upper surface (outer surface) of the external terminal may be flush with the upper surface of the terminal mounting portion 111 of the outer lid 11 or may be disposed below the upper surface of the terminal mounting portion 111.

  Moreover, in the said embodiment, the case where the screw hole 913 was provided in the external terminal 91 was illustrated. However, the external terminal may be provided with a male screw, and the bus bar to which the external terminal is connected may be provided with the female screw. Moreover, you may join an external terminal to a bus-bar by fastening the external thread and nut of an external terminal.

  Moreover, in the said embodiment, the case where the resin member 15 which is a 2nd resin body was formed from translucent resin was illustrated. However, the second resin body may be formed of a non-translucent resin. In this case, for joining the second resin body and the first resin body, a joining method other than laser transmission welding such as pressure bonding or adhesion is used.

  Moreover, in this Embodiment, the outer cover 11 was illustrated as a 1st resin body. However, the first resin body may be anything as long as it forms a part of the exterior body. For example, a main body part that is a part of the exterior body may be used as the first resin body.

  Moreover, in the said embodiment, after the external terminal 91 and the bus-bar 81 were joined, the case where the resin member 15 and the exterior body 10 were joined was illustrated. However, the external terminal and the bus bar may be joined after the resin member and the exterior body are joined.

  In addition, embodiments constructed by arbitrarily combining the constituent elements included in the above-described embodiment and its modifications are also included in the scope of the present invention.

  The present invention can be applied to a power storage device including a power storage element such as a lithium ion secondary battery.

DESCRIPTION OF SYMBOLS 1 Power storage device 10 Exterior body 11, 11a, 11b, 11c Outer lid 12 Main body parts 15, 15b, 15c Resin members 16, 16c Joint part 17 Bus bar plate 17a Bus bar opening part 20 Power storage element 21 Container 22 Electrode terminal 33 Bus bar 60, 70 Bus bar cover 80 Connection unit 81, 82 Bus bar (conductive member)
83, 84 Screw 91, 91b, 91c, 92 External terminal 111, 111a, 111b, 111c Terminal mounting portion 112, 811 Through hole 118 Rib 161 First joint 162 Second joint 911 Connection 912, 912b, 912c Base part 913 Screw hole

Claims (5)

A first resin body that forms part of the exterior body;
A conductive member housed in the exterior body;
An external terminal joined to the conductive member and exposed from the first resin body;
A second resin body fixed to the external terminal,
The power storage device, wherein the second resin body is joined to the first resin body over the entire circumference of the external terminal in a state of overlapping the first resin body. The power storage device according to claim 1, wherein the second resin body is disposed outside the first resin body. The power storage device according to claim 1, wherein the second resin body and the external terminal are insert molded bodies. The power storage device according to any one of claims 1 to 3, wherein the second resin body is formed of a light transmissive resin. The second resin body and the external terminal are provided with a first joint that joins the second resin body and the external terminal over the entire circumference of the external terminal,
The second resin body and the first resin body are provided with a second joint portion that joins the second resin body and the first resin body over the entire circumference of the external terminal. 2. The power storage device according to 2.

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