Power storage module

Abstract

To provide a power storage module capable of suppressing breakage of a terminal and a terminal housing part.SOLUTION: The energy storage module 100 includes an electrode stacked body 10 having a plurality of electrodes stacked along the Z-axis direction, a sealing body 20 which surrounds the electrode stacked body 10 as viewed in the Z-axis direction and seals an inner space S formed between the electrodes disposed adjacently to each other in the Z-axis direction, and terminals 300 which are mounted on the electrodes and extend to the outside of the sealing body 20. The terminal 300 includes a connecting portion 310 connected to the electrode, a protruding portion 330 extending along the Y-axis direction and protruding to the outside of the sealing body 20, and a deformable portion 320 disposed between the connecting portion 310 and the protruding portion 330. The deformable portion 320 includes a first flat plate portion 321 and a second flat plate portion 322 connected to the first flat plate portion 321. The first flat plate portion 321 is more easily elastically deformed in the Z-axis direction than the second flat plate portion 322. The second flat plate portion 322 is more easily elastically deformed in the X-axis direction than the first flat plate portion 321.SELECTED DRAWING: Figure 2

Description

[Technical Field]

[0001] The present disclosure relates to an energy storage module. [Background technology]

[0002] Patent Document 1 discloses a secondary battery having a plurality of electrodes stacked with a solid electrolyte interposed therebetween and a sealed portion. Each of the electrodes is connected to a tab for detecting the voltage of the electrode. The tab extends to the outside of the sealed portion. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Laid-Open No. 2004-319362 Summary of the Invention [Problem to be solved by the invention]

[0004] The ends of the terminals that extend to the outside of the secondary battery, such as the tabs described above, are sometimes housed in a resin member to facilitate connection to a voltage measuring device. The resin member is provided with multiple terminal housings that can separately house each of the multiple terminal ends. If the terminals are not positioned appropriately, the terminals or the terminal housings may be damaged when the resin member is attached.

[0005] The present disclosure provides an energy storage module that can suppress damage to terminals and terminal accommodating portions. [Means for solving the problem]

[0006] The energy storage module according to the present disclosure comprises an electrode stack having a plurality of electrodes stacked along a first direction; a sealing body that surrounds the electrode stack when viewed from the first direction and seals an internal space formed between adjacent electrodes in the first direction; and a terminal that is provided on the electrode and extends to the outside of the sealing body, wherein the terminal has a connection portion connected to the electrode, a protrusion that extends along a second direction perpendicular to the first direction and protrudes outside the sealing body, and a deformation portion that is arranged between the connection portion and the protrusion, and the deformation portion has a first flat plate portion and a second flat plate portion connected to the first flat plate portion, wherein the first flat plate portion has a first surface that extends in the second direction and in a third direction perpendicular to the first and second directions and is more easily elastically deformed in the first direction than the second flat plate portion, and the second flat plate portion has a second surface that extends in the first direction and the second direction and is more easily elastically deformed in the third direction than the first flat plate portion.

[0007] In the above energy storage module, the deformation portion of the terminal includes a first flat plate portion configured to easily elastically deform in a first direction and a second flat plate portion configured to easily elastically deform in a second direction. This allows the protrusion of the terminal to be moved in the first direction and the second direction and positioned appropriately. As a result, damage to the terminal and the terminal accommodating portion can be suppressed.

[0008] The deformation portion may further have a third flat plate portion connected to the second flat plate portion, and the third flat plate portion may have a third surface that extends in the first direction and is inclined in the second and third directions, and may be more easily elastically deformed in the third direction than the first flat plate portion.

[0009] The deformation portion may further have a fourth flat plate portion connected to the third flat plate portion, and the fourth flat plate portion may have a fourth surface extending in the second direction and the third direction, and may be more easily elastically deformed in the third direction than the first flat plate portion.

[0010] The protrusion may include a tip that tapers toward the tip in the second direction.

[0011] The protrusion may have a pair of flat outer surfaces facing opposite sides in a direction perpendicular to the second direction.

[0012] The connecting portion may have a fifth surface that is flush with the first surface.

[0013] The protrusion may have a hollow structure, and the terminal may have a partition wall between the protrusion and the deformation portion.

[0014] The partition may extend in the first direction and in the third direction.

[0015] The energy storage module may further include a resin part having a terminal accommodating portion that accommodates the protrusion, and the terminal accommodating portion may have a tapered portion in which the length of the terminal accommodating portion in the first direction decreases as it moves away from the sealing body in the second direction.

[0016] The energy storage module may further include a resin part having a terminal accommodating portion that accommodates the protrusion, the terminal accommodating portion having a tapered portion in which the length of the terminal accommodating portion in the first direction decreases as it moves away from the electrode stack in the second direction, the protrusion having a hollow structure, and the terminal having a partition wall between the protrusion and the deformation portion, the partition wall being disposed in the tapered portion. [Effects of the Invention]

[0017] According to the present disclosure, it is possible to provide an energy storage module that can suppress damage to the terminals and the terminal accommodating portions. [Brief explanation of the drawings]

[0018] [Figure 1] FIG. 1 is a perspective view of an electricity storage module according to one embodiment. [Figure 2] FIG. 2 is a cross-sectional view of the electricity storage module. [Figure 3] FIG. 3 is a cross-sectional view of the electricity storage module. [Figure 4] FIG. 4 is a perspective view of the terminal. [Figure 5] FIG. 5 is a plan view of the terminal. [Figure 6] FIG. 6 is a side view of the terminal. [Figure 7] 7(a), 7(b), and 7(c) are cross-sectional views of the terminal. [Figure 8] FIG. 8 is a plan view showing the positional relationship between the terminal and the welded portion before the resin part is attached. [Figure 9] FIG. 9 is a perspective view of a terminal according to a modified example. [Figure 10] FIG. 10 is a plan view of a terminal according to a modified example. [Figure 11] FIG. 11 is a side view of a terminal according to a modified example. [Figure 12] 12(a), 12(b), and 12(c) are cross-sectional views of terminals according to modified examples. DETAILED DESCRIPTION OF THE INVENTION

[0019] An embodiment will be described below with reference to the drawings. In the description of the drawings, identical or equivalent elements are denoted by the same reference numerals, and redundant description may be omitted. In the description, a Cartesian coordinate system defined by the X-axis, Y-axis, and Z-axis shown in the drawings may be referenced.

[0020] As shown in FIG. 1, an energy storage module 100 according to one embodiment includes a module main body 200, a plurality of terminals 300, and a resin part 400. FIG. 1 schematically illustrates a state before the resin part 400 is attached. The energy storage module 100 is, for example, a nickel-metal hydride secondary battery or a lithium-ion secondary battery. The energy storage module 100 may also be, for example, an electric double layer capacitor. In this embodiment, the energy storage module 100 is a lithium-ion secondary battery.

[0021] As shown in FIGS. 2 and 3, the module main body 200 includes an electrode stack 10 and a sealing body 20. FIG. 2 schematically illustrates a state before a resin part 400 is attached. FIG. 3 schematically illustrates a state after the resin part 400 is attached. The electrode stack 10 has, for example, a rectangular parallelepiped shape. The electrode stack 10 has a plurality of electrodes stacked along the Z-axis direction (first direction). The plurality of electrodes includes a plurality of bipolar electrodes 11, a positive terminal electrode 12, and a negative terminal electrode 13. Separators 14 are interposed between adjacent electrodes.

[0022] The bipolar electrode 11 includes a current collector 15, a first active material layer 16, and a second active material layer 17. When viewed from the Z-axis direction, the current collector 15 has, for example, a rectangular shape. The current collector 15 includes a surface 15a and a surface 15b opposite to the surface 15a.

[0023] The first active material layer 16 is provided on the surface 15a. The first active material layer 16 is, for example, a positive electrode active material layer. When viewed from the Z-axis direction, the first active material layer 16 has, for example, a rectangular shape. The surface 15a includes an uncoated region where the first active material layer 16 is not provided. When viewed from the Z-axis direction, the uncoated region surrounds the first active material layer 16.

[0024] The second active material layer 17 is provided on the surface 15b. The polarity of the second active material layer 17 is different from the polarity of the first active material layer 16. The second active material layer 17 is, for example, a negative electrode active material layer. When viewed from the Z-axis direction, the second active material layer 17 has, for example, a rectangular shape. The surface 15b includes an uncoated region where the second active material layer 17 is not provided. When viewed from the Z-axis direction, the uncoated region surrounds the second active material layer 17. When viewed from the Z-axis direction, the area of ​​the second active material layer 17 is larger than the area of ​​the first active material layer 16. When viewed from the Z-axis direction, the outer edge of the second active material layer 17 is located outside the outer edge of the first active material layer 16.

[0025] The multiple bipolar electrodes 11 are stacked so that the first active material layer 16 of one bipolar electrode 11 faces the second active material layer 17 of another bipolar electrode 11. In other words, the multiple bipolar electrodes 11 are stacked so that, of adjacent bipolar electrodes 11, the surface 15a of the current collector 15 of one bipolar electrode 11 faces the surface 15b of the current collector 15 of the other bipolar electrode 11.

[0026] The positive terminal electrode 12 is disposed on one side of the bipolar electrodes 11 in the Z-axis direction. The positive terminal electrode 12 includes a current collector 15 and a first active material layer 16. The positive terminal electrode 12 differs from the bipolar electrodes 11 primarily in that it does not include a second active material layer 17. The other configurations of the positive terminal electrode 12 may be the same as those of the bipolar electrode 11. The first active material layer 16 of the positive terminal electrode 12 faces the second active material layer 17 of the bipolar electrode 11. That is, the positive terminal electrode 12 is stacked such that the surface 15a of the current collector 15 of the positive terminal electrode 12 faces the surface 15b of the current collector 15 of the bipolar electrode 11 adjacent to the positive terminal electrode 12.

[0027] The negative terminal electrode 13 is disposed on the other side of the plurality of bipolar electrodes 11 in the Z-axis direction. The negative terminal electrode 13 has a current collector 15 and a second active material layer 17. The negative terminal electrode 13 differs from the bipolar electrode 11 mainly in that it does not have a first active material layer 16. Other configurations of the negative terminal electrode 13 may be the same as those of the bipolar electrode 11. The second active material layer 17 of the negative terminal electrode 13 faces the first active material layer 16 of the bipolar electrode 11. In other words, the negative terminal electrode 13 is stacked such that the surface 15b of the current collector 15 of the negative terminal electrode 13 faces the surface 15a of the current collector 15 of the bipolar electrode 11 adjacent to the negative terminal electrode 13.

[0028] The outer edges of the current collectors 15 of the electrodes 11, 12, and 13 form the side surfaces of the electrode stack 10. Internal spaces S for accommodating an electrolyte are formed between the bipolar electrodes 11, between the bipolar electrodes 11 and the positive terminal electrode 12, and between the bipolar electrodes 11 and the negative terminal electrode 13.

[0029] Separators 14 are disposed between the bipolar electrodes 11, between the bipolar electrodes 11 and the positive terminal electrode 12, and between the bipolar electrodes 11 and the negative terminal electrode 13. The separators 14 are disposed between the opposing first and second active material layers 16 and 17. The separators 14 are, for example, sheet-shaped. When viewed from the Z-axis direction, the outer edges of the separator 14 are located further outward than the outer edges of the first and second active material layers 16 and 17. The separators 14 allow charge carriers such as lithium ions to pass through. The separators 14 separate the adjacent electrodes 11, 12, and 13, thereby preventing electrical shorts due to contact between the electrodes 11, 12, and 13. The separators 14 absorb and retain the electrolyte.

[0030] The current collector 15 has the function of maintaining the flow of current in the first active material layer 16 and the second active material layer 17 during discharging or charging of the energy storage module 100. The current collector 15 is, for example, a chemically inactive electrical conductor. The material of the current collector 15 is, for example, a metal material, a conductive resin material, a conductive inorganic material, etc. The conductive resin material is, for example, a conductive polymer material, or a non-conductive polymer material to which a conductive filler has been added, etc. When the current collector 15 has multiple layers, the material of each layer may be any of the materials described above. A coating layer may be formed on the surface of the current collector 15. The coating layer may be formed by a known method such as plating or spray coating.

[0031] The current collector 15 has, for example, a plate, foil, sheet, film, or mesh shape. The current collector 15 may be, for example, an aluminum foil, copper foil, nickel foil, titanium foil, or stainless steel foil. The current collector 15 may be an alloy foil or clad foil of the above metals. When the current collector 15 is in the form of a foil, the thickness of the current collector 15 is, for example, 1 μm or more and 100 μm or less. The current collector 15 may be a laminate having multiple metal layers. The current collector 15 may be, for example, a laminate in which an aluminum layer and a copper layer are integrated. The current collector 15 may include, for example, an aluminum foil and copper plating formed on one side of the aluminum foil. The current collector 15 may include multiple metal foils bonded together with a conductive adhesive.

[0032] The first active material layer 16 includes a positive electrode active material capable of absorbing and releasing charge carriers such as lithium ions. The positive electrode active material is, for example, a composite oxide, metallic lithium, or sulfur. The composite oxide includes, for example, at least one of iron, manganese, titanium, nickel, cobalt, and aluminum, and lithium. The composite oxide is, for example, olivine-type lithium iron phosphate (LiFePO4), LiCoO2, LiNiMnCoO2, or the like.

[0033] The second active material layer 17 contains a negative electrode active material capable of absorbing and releasing charge carriers such as lithium ions. Examples of the negative electrode active material include graphite, artificial graphite, highly oriented graphite, mesocarbon microbeads, hard carbon, soft carbon, metal compounds, elements or compounds thereof that can be alloyed with lithium, and boron-doped carbon. Examples of the elements that can be alloyed with lithium include silicon and tin.

[0034] Each of the first active material layer 16 and the second active material layer 17 may contain a binder and a conductive additive in addition to the active material. The binder functions to bind the active material or conductive additive together and maintain the conductive network in the electrode. Examples of binders include fluorine-containing resins such as polyvinylidene fluoride, polytetrafluoroethylene, and fluororubber; thermoplastic resins such as polypropylene and polyethylene; imide resins such as polyimide and polyamideimide; alkoxysilyl group-containing resins; acrylic resins such as polyacrylic acid and polymethacrylic acid; styrene-butadiene rubber; carboxymethyl cellulose; alginates such as sodium alginate and ammonium alginate; water-soluble cellulose ester crosslinked bodies; and starch-acrylic acid graft polymers. These binders may be used alone or in combination. The conductive additive is a conductive material that enhances electrical conductivity. Examples of conductive additives include acetylene black, carbon black, and graphite. Examples of viscosity-adjusting solvents include N-methyl-2-pyrrolidone.

[0035] Formation of the first active material layer 16 on the surface 15a and the second active material layer 17 on the surface 15b can be achieved by conventional methods such as roll coating, die coating, dip coating, doctor blade coating, spray coating, and curtain coating. Specifically, an active material, a solvent, and, if necessary, a binder and a conductive additive are mixed to produce a slurry-like active material layer-forming composition. The active material layer-forming composition is then applied to the surface 15a or the surface 15b and dried. Examples of the solvent include N-methyl-2-pyrrolidone, methanol, methyl isobutyl ketone, and water. The dried electrode may be compressed to increase its density.

[0036] The electrolyte is contained in the internal space S. The separator 14 is impregnated with the electrolyte. The electrolyte is, for example, a liquid containing a non-aqueous solvent and an electrolyte salt dissolved in the non-aqueous solvent. The electrolyte salt of the electrolyte is, for example, a known lithium salt such as LiClO4, LiAsF6, LiPF6, LiBF4, LiCF3SO3, LiN(FSO2)2, or LiN(CF3SO2)2. The non-aqueous solvent is, for example, a cyclic carbonate, a cyclic ester, a chain carbonate, a chain ester, or an ether. Two or more of these known solvent materials may be used in combination.

[0037] The sealing body 20 surrounds the electrode stack 10 when viewed from the Z-axis direction. The sealing body 20 seals the internal space S formed between adjacent electrodes in the Z-axis direction. The sealing body 20 includes a sealing member 21, a spacer 22, a welded portion 23, and a resin portion 24. The sealing member 21 has, for example, a rectangular frame shape. The sealing member 21 covers the peripheral portion of each current collector 15. The sealing member 21 is provided on the surface 15a and the surface 15b of each current collector 15. The sealing member 21 surrounds the first active material layer 16 and the second active material layer 17 when viewed from the Z-axis direction. The inner edge of the sealing member 21 is spaced from the first active material layer 16 and the second active material layer 17. The sealing member 21 is welded to the current collector 15.

[0038] The spacer 22 has, for example, a rectangular frame shape. The spacer 22 is provided between adjacent sealing members 21. The spacer 22 is sandwiched between adjacent sealing members 21. The inner peripheral portion of the spacer 22 overlaps with the second active material layer 17 when viewed from the Z-axis direction. The inner peripheral portion of the spacer 22 is located between the surface 15a of the current collector 15 and the second active material layer 17. The welded portion 23 is formed by welding the outer edges of each sealing member 21 and each spacer 22 together. The welded portion 23 has, for example, a rectangular cylindrical shape. The resin portion 24 is provided by injection molding so as to fill the space between the welded portion 23 and the resin part 400.

[0039] The sealing member 21, the spacer 22, and the resin portion 24 are each made of a material such as acid-modified polyethylene (acid-modified PE), acid-modified polypropylene (acid-modified PP), polyethylene, or polypropylene. The sealing member 21 and the spacer 22 are each electrolyte-resistant. The sealing member 21 and the spacer 22 may be made of the same material or different materials. In this embodiment, the sealing member 21 is made of, for example, acid-modified polyethylene or acid-modified polypropylene. In this embodiment, the spacer 22 is made of, for example, polyethylene or polypropylene. Acid-modified polyethylene and acid-modified polypropylene are more easily bonded to metal than non-acid-modified polyethylene and non-acid-modified polypropylene. When the current collector 15 is made of metal, the bonding strength of the sealing member 21 to the current collector 15 can be improved by making the sealing member 21 from acid-modified polyethylene or acid-modified polypropylene.

[0040] The terminals 300 are provided on the electrodes and detect the voltages of the electrodes. Each of the multiple terminals 300 is provided on a corresponding one of the multiple electrodes. For example, the number of terminals 300 is the same as the number of electrodes, with one terminal 300 provided for each electrode. The terminals 300 are provided on the surface 15b of each current collector 15 and electrically connected to the surface 15b. The terminals 300 are provided between the surface 15b of the current collector 15 and the seal member 21. The terminals 300 are formed of a metal such as stainless steel.

[0041] The terminals 300 extend from the inside of the sealing body 20 to the outside of the sealing body 20. For example, as shown in FIG. 1, the multiple terminals 300 are arranged in a predetermined region on one side surface of the module main body 200 that is perpendicular to the Y-axis direction. In this predetermined region, the multiple terminals 300 are arranged so as to be aligned linearly in the Z-axis direction and the X-axis direction, i.e., in a grid pattern. The distance between the terminals 300 in the X-axis direction is, for example, 5 mm or more and 30 mm or less. The distance between the terminals 300 in the Z-axis direction is, for example, 1 mm or more and 10 mm or less.

[0042] The resin part 400 is a member that protects the multiple terminals 300 protruding from the module main body 200. As shown in FIG. 3, the resin part 400 is provided with multiple terminal accommodating sections 410 that individually accommodate each of the multiple terminals 300. The multiple terminal accommodating sections 410 are arranged in a lattice pattern corresponding to the multiple terminals 300. The resin part 400 has a side surface 401 that faces the welded portion 23 in the Y-axis direction, and a side surface 402 that faces the opposite side in the Y-axis direction from the side surface 401. The terminal accommodating section 410 is configured as a hole that penetrates the resin part 400 in the Y-axis direction.

[0043] The terminal accommodating portion 410 has a wide portion 411, a tapered portion 412, a narrow portion 413, and an insertion portion 414. The wide portion 411, the tapered portion 412, the narrow portion 413, and the insertion portion 414 are arranged in this order from the side surface 401 to the side surface 402. The wide portion 411 opens to the side surface 401. The tapered portion 412 connects the wide portion 411 and the narrow portion 413. The insertion portion 414 opens to the side surface 402. A connector (not shown) of a voltage measuring device is inserted into the insertion portion 414.

[0044] The length L1 of the narrow portion 413 in the Z axis direction is shorter than the length L2 of the wide portion 411 in the Z axis direction. Although not shown in the figure, the length of the narrow portion 413 in the X axis direction is shorter than the length of the wide portion 411 in the X axis direction. The size of the wide portion 411 (the length in the Z axis direction and the length in the X axis direction) is set so as to provide a sufficient clearance with respect to the size of the protruding portion 330. The size of the narrow portion 413 is set so as to provide a slight clearance with respect to the size of the protruding portion 330. The size of the narrow portion 413 is set to be approximately the same as the size of the protruding portion 330.

[0045] The tapered portion 412 is formed in a tapered shape. The size of the tapered portion 412 gradually decreases with increasing distance from the electrode stack 10 in the Y-axis direction. The length of the tapered portion 412 in the Z-axis direction changes from length L2 to length L1. Because the size of the wide portion 411 is larger than the size of the narrow portion 413, it is easy to insert the terminal 300 into the wide portion 411 (terminal accommodating portion 410). The tapered portion 412 makes it possible to guide the position of the terminal 300. Furthermore, the tapered portion 412 prevents the protruding portion 330 from being covered with resin when the resin portion 24 is formed by injection molding.

[0046] 1 to 6, terminal 300 extends along the Y-axis direction as a whole. Terminal 300 has a connecting portion 310, a deforming portion 320, a protruding portion 330, and a partition wall 340. Connecting portion 310 is one end portion (base end) in the Y-axis direction, and protruding portion 330 is the other end portion (tip end) in the Y-axis direction. Deforming portion 320 is disposed between connecting portion 310 and protruding portion 330 in the Y-axis direction. Terminal 300 is formed, for example, by bending a single thin metal plate having a thickness of 0.05 mm to 0.5 mm.

[0047] The connection portion 310 is a portion connected to an electrode. The connection portion 310 is a thin metal plate whose thickness direction is in the Z-axis direction. The connection portion 310 has a main surface 310a (fifth surface) extending in the Y-axis direction and the X-axis direction. The main surface 310a is continuous with a main surface 321a (first surface) of the first flat plate portion 321 (described later) and forms the same plane. When viewed from the Z-axis direction, the connection portion 310 has, for example, a rectangular shape with its longer side oriented in the Y-axis direction and its shorter side oriented in the X-axis direction. The connection portion 310 extends in the X-axis direction and the Y-axis direction. The connection portion 310 is inserted into the electrode stack 10 and surface-bonded to the surface 15b of the current collector 15. The connection portion 310 is, for example, ultrasonically welded to the surface 15b of the current collector 15. Because the connection portion 310 is made of a thin plate, tearing (foil tearing) of the electrode foil constituting the current collector 15 is unlikely to occur.

[0048] The protrusion 330 extends along the Y-axis direction and protrudes outward from the sealing body 20. The protrusion 330 is a rod-shaped member whose axis is in the Y-axis direction. The protrusion 330 has a hollow structure. The hollow portion of the protrusion 330 extends in the Y-axis direction. The protrusion 330 is formed by deforming a thin metal plate into a cylindrical or grooved shape. The protrusion 330 includes a tip portion 330b that tapers toward the tip 330a in the Y-axis direction. The tapered shape of the tip portion 330b facilitates insertion of the protrusion 330 into the terminal accommodating portion 410 of the resin part 400. The protrusion 330 is connected to a connector of a voltage measuring device. The outer surface of the protrusion 330 is, for example, gold-plated. This facilitates electrical continuity between the terminal 300 and the connector of the voltage measuring device.

[0049] The protruding portion 330 includes a first portion 331, a second portion 332, and a third portion 333. One end of the first portion 331 in the Y-axis direction is connected to the deformation portion 320. As shown in FIG. 7(a), the first portion 331 is formed in a groove-like shape with a U-shaped cross section. The first portion 331 has a pair of flat outer surfaces 331a, 331b facing opposite directions in the X-axis direction.

[0050] One end of the second portion 332 in the Y-axis direction is connected to the other end of the first portion 331 in the Y-axis direction. As shown in FIG. 7(b), the second portion 332 is formed in a rectangular ring shape in cross section. The second portion 332 has a pair of planar outer surfaces 332a and 332b facing opposite sides in the X-axis direction. The second portion 332 has a pair of planar outer surfaces 332c and 332d facing opposite sides in the Z-axis direction. For example, by using the pair of outer surfaces 332a and 332b or the pair of outer surfaces 332c and 332d as conductive surfaces that come into contact with a connector of a voltage measuring device, it is easy to ensure the area of ​​the conductive surfaces.

[0051] One end of the third portion 333 in the Y-axis direction is connected to the other end of the second portion 332 in the Y-axis direction. As shown in Fig. 7(c), the third portion 333 is formed to have a circular cross section. The other end of the third portion 333 in the Y-axis direction is the tip 330a. The third portion 333 includes a tip portion 330b.

[0052] The deforming portion 320 deforms to match the position of the corresponding terminal accommodating portion 410, making it easier to insert the protruding portion 330 into the corresponding terminal accommodating portion 410. The deforming portion 320 includes a first flat plate portion 321, a second flat plate portion 322, a third flat plate portion 323, and a fourth flat plate portion 324. One end of the first flat plate portion 321 in the Y-axis direction is connected to the connecting portion 310. The thickness direction of the first flat plate portion 321 is the Z-axis direction, and the first flat plate portion 321 is more easily elastically deformed in the Z-axis direction than the second flat plate portion 322. The first flat plate portion 321 has a main surface 321a (first surface) extending in the Y-axis direction and the X-axis direction. As described above, the main surface 321a is continuous with the main surface 310a and forms the same plane.

[0053] When viewed from the Z-axis direction, the first flat plate portion 321 has, for example, a rectangular shape with its longer side oriented in the Y-axis direction and its shorter side oriented in the X-axis direction. The first flat plate portion 321 and the connecting portion 310 are connected so that their centers in the X-axis direction coincide with each other. The width of the first flat plate portion 321 in the X-axis direction is shorter than the width of the connecting portion 310 in the X-axis direction. This makes the first flat plate portion 321 more likely to deform in the Z-axis direction. The second moment of area of ​​the first flat plate portion 321 in the Z-axis direction is smaller than the second moment of area in the X-axis direction, and the first flat plate portion 321 is more likely to elastically deform in the Z-axis direction.

[0054] One end of the second flat plate portion 322 in the Y-axis direction is connected to the other end of the first flat plate portion 321 in the Y-axis direction. The thickness direction of the second flat plate portion 322 is the X-axis direction. The second flat plate portion 322 has a smaller second moment of area in the X-axis direction than the second moment of area in the Z-axis direction, making it more susceptible to elastic deformation in the X-axis direction. The second flat plate portion 322 is more susceptible to elastic deformation in the X-axis direction than the first flat plate portion 321. The second flat plate portion 322 has a main surface 322a (second surface) extending in the Y-axis and Z-axis directions. When viewed from the X-axis direction, the second flat plate portion 322 has, for example, a substantially rectangular shape with its longer side extending in the Y-axis direction and its shorter side extending in the Z-axis direction. The first flat plate portion 321 and the second flat plate portion 322 are connected to each other via a bent portion formed, for example, by bending a thin metal plate at a right angle.

[0055] One end of the third flat plate portion 323 in the Y-axis direction is connected to the other end of the second flat plate portion 322 in the Y-axis direction. The third flat plate portion 323 extends in the Z-axis direction and has a main surface 323a (third surface) that is inclined in the X-axis and Y-axis directions. The third flat plate portion 323 is more easily elastically deformed in the X-axis direction than the first flat plate portion 321, and is less easily elastically deformed in the Z-axis direction than the first flat plate portion 321. The second flat plate portion 322 and the third flat plate portion 323 are connected to each other via a bent portion formed by bending a thin metal plate, for example.

[0056] One end of the fourth flat plate portion 324 in the Y-axis direction is connected to the other end of the third flat plate portion 323 in the Y-axis direction. The thickness direction of the fourth flat plate portion 324 is the X-axis direction. The fourth flat plate portion 324 is more easily elastically deformed in the X-axis direction than the first flat plate portion 321, and is less easily elastically deformed in the Z-axis direction than the first flat plate portion 321. In the fourth flat plate portion 324, the second flat plate portion 322 and the fourth flat plate portion 324 are arranged parallel to each other. The fourth flat plate portion 324 has a main surface 324a (fourth surface) extending in the Y-axis direction and the Z-axis direction. The third flat plate portion 323 and the fourth flat plate portion 324 are connected to each other via a bent portion formed by bending a thin metal plate, for example.

[0057] The second flat plate portion 322, the third flat plate portion 323, and the fourth flat plate portion 324 are all more susceptible to elastic deformation in the X-axis direction than the first flat plate portion 321. When ultrasonically welding the terminal 300 to the current collector 15, there is a risk that a fragile portion of the terminal 300 may be damaged. In this embodiment, the third flat plate portion 323, which extends in a direction inclined with respect to the Y-axis direction, is provided between the second flat plate portion 322 and the fourth flat plate portion 324, which extend in the Y-axis direction. This configuration can prevent the fragile portion of the terminal 300 from being damaged by vibrations when ultrasonically welding the connection portion 310 to the current collector 15. The fragile portion of the terminal 300 is, for example, a bent portion of the metal plate or a portion of the metal plate where the width is narrow.

[0058] The partition wall 340 is provided between the protruding portion 330 and the deforming portion 320. The partition wall 340 separates the hollow portion of the protruding portion 330 from the space in which the deforming portion 320 is provided. The partition wall 340 extends in the Z-axis direction and the X-axis direction. The partition wall 340 is disposed in the tapered portion 412 of the terminal accommodating portion 410.

[0059] When the resin portion 24 is formed by injection molding, if the resin penetrates beyond the deformed portion 320 and adheres to the second portion 332 of the protruding portion 330, the area of ​​the conductive surface of the deformed portion 320 will be reduced. This may result in poor contact between the terminal 300 and the connector of the voltage measuring device. The partition wall 340 functions as a blocking portion that prevents the resin from penetrating into the protruding portion 330. The partition wall 340 has an outer surface that is continuous with the outer surface 331a of the first portion 331 of the protruding portion 330 via a bent portion. The partition wall 340 is formed by bending the end of a metal plate that forms the side wall of the groove in the first portion 331.

[0060] FIG. 8 shows the positional relationship between the terminal 300 and the sealing body 20. Here, the sealing body 20 is indicated by a dashed line. As shown in FIG. 8, at least a portion of the deforming portion 320, together with the protruding portion 330, protrudes outside the welded portion 23. In this example, at least a portion of the first flat plate portion 321 and the entire second flat plate portion 322 protrude outside the welded portion 23. Therefore, before the resin part 400 is attached, i.e., before the resin part 24 is provided, the deforming portion 320 can elastically deform in the Z-axis direction and the X-axis direction. By attaching the resin part 400 to the terminal 300 in this state, the protruding portion 330 is positioned appropriately, and damage to the terminal 300 and the terminal accommodating portion 410 can be suppressed.

[0061] After the resin part 400 is attached to the terminal 300, resin is injected between the resin part 400 and the welded portion 23 by injection molding to form the resin part 24. This fixes the resin part 400 to the module main body 200. The resin also enters the interior of the terminal accommodating part 410 from the opening on the side surface 401 side of the terminal accommodating part 410. Therefore, the resin part 24 is formed so as to overlap a part of the protruding part 330 when viewed from the Z-axis direction.

[0062] Although examples of the embodiments of the present disclosure have been described above with reference to the drawings, the present disclosure is not limited to the above embodiments.

[0063] A terminal 300A according to a modification shown in FIGS. 9 to 12 differs from the terminal 300 according to the embodiment (see FIGS. 4 to 7) in that it includes a protrusion 330A instead of the protrusion 330. The protrusion 330A also includes a tip 330b that tapers toward the tip 330a in the Y-axis direction. As shown in FIG. 12(a), the first portion 331 of the protrusion 330A is formed in a groove-like shape with a U-shaped cross section. The first portion 331 of the protrusion 330A has a narrower groove width and a deeper groove depth than the first portion 331 of the protrusion 330 (see FIG. 7(a)). The dimensions of the first portion 331 of the protrusion 330 in the X-axis direction and the Z-axis direction are equal, whereas the dimension of the first portion 331 of the protrusion 330A in the X-axis direction is shorter than the dimension of the first portion 331 of the protrusion 330A in the Z-axis direction.

[0064] As shown in FIG. 12(b), the second portion 332 of the protrusion 330A is formed in a groove shape with a U-shaped cross section, unlike the second portion 332 of the protrusion 330 (see FIG. 7(b)). In the protrusion 330A, the width of the groove in the second portion 332 is equal to the width of the groove in the first portion 331, and the depth of the groove in the second portion 332 is shallower than the depth of the groove in the first portion 331. In the second portion 332 of the protrusion 330, the dimensions in the X-axis direction and the Z-axis direction are equal, whereas in the second portion 332 of the protrusion 330A, the dimension in the X-axis direction is shorter than the dimension in the Z-axis direction.

[0065] The third portion 333 of the protrusion 330A (see FIG. 12(c)) includes a pair of side plates 334 that face each other in the X-axis direction. The pair of side plates 334 are spaced apart in the X-axis direction. In the protrusion 330A as well, the tip 330b has a shape that tapers toward the tip 330a. In the tip 330b, the distance between the pair of side plates 334 in the X-axis direction becomes shorter as the tip 330a is approached. In the tip 330b, the length of the pair of side plates 334 in the Z-axis direction also becomes shorter as the tip 330a is approached.

[0066] The same effects as those of the power storage module 100 can be obtained in the power storage module including the terminal 300A according to the modified example.

[0067] In terminals 300 and 300A, for example, the plate area of ​​deforming portion 320 may be partially reduced. In this case, deforming portion 320 becomes more likely to deform elastically. In terminals 300 and 300A, for example, deforming portion 320 may be formed of a metal plate formed into an accordion-like shape. In this case, deforming portion 320 becomes more likely to deform elastically.

[0068] The form of the present disclosure can be shown as follows. [Article 1] an electrode stack having a plurality of electrodes stacked along a first direction; a sealing body that surrounds the electrode stack when viewed from the first direction and seals an internal space formed between the electrodes adjacent to each other in the first direction; a terminal provided on the electrode and extending to the outside of the sealing body; Equipped with the terminal has a connection portion connected to the electrode, a protrusion extending along a second direction perpendicular to the first direction and protruding to the outside of the sealing body, and a deformation portion disposed between the connection portion and the protrusion, the deformation portion has a first flat plate portion and a second flat plate portion connected to the first flat plate portion, the first flat plate portion has a first surface extending in the second direction and a third direction perpendicular to the first direction and the second direction, and is more easily elastically deformed in the first direction than the second flat plate portion; the second flat plate portion has a second surface extending in the first direction and the second direction, and is more easily elastically deformed in the third direction than the first flat plate portion; Energy storage module. [Clause 2] the deformation portion further includes a third plate portion connected to the second plate portion, the third flat plate portion has a third surface that extends in the first direction and is inclined in the second direction and the third direction, and is more easily elastically deformed in the third direction than the first flat plate portion; 1. The energy storage module according to clause 1. [Article 3] the deformation portion further includes a fourth plate portion connected to the third plate portion, the fourth flat plate portion has a fourth surface extending in the second direction and the third direction, and is more easily elastically deformed in the third direction than the first flat plate portion; 2. The energy storage module according to clause 2. [Article 4] The protrusion includes a tip portion that tapers toward the tip in the second direction. The electricity storage module according to any one of items 1 to 3. [Article 5] The protrusion has a pair of flat outer surfaces facing opposite sides in a direction perpendicular to the second direction. The electricity storage module according to any one of items 1 to 4. [Article 6] The connection portion has a fifth surface that is flush with the first surface. 6. The power storage module according to any one of items 1 to 5. [Article 7] The protrusion has a hollow structure, The terminal has a partition wall between the protruding portion and the deforming portion. The electricity storage module according to any one of items 1 to 6. [Article 8] The partition wall extends in the first direction and the third direction. 7. The energy storage module according to clause 7. [Article 9] a resin part provided with a terminal accommodating portion that accommodates the protrusion, The terminal accommodating portion has a tapered portion in which the length of the terminal accommodating portion in the first direction decreases as the terminal accommodating portion becomes farther from the sealing body in the second direction. The electricity storage module according to any one of clauses 1 to 8. [Article 10] a resin part provided with a terminal accommodating portion that accommodates the protrusion, the terminal accommodating portion has a tapered portion in which the length of the terminal accommodating portion in the first direction decreases as the terminal accommodating portion becomes farther from the electrode stack in the second direction; The protrusion has a hollow structure, the terminal has a partition wall between the protruding portion and the deforming portion, The partition wall is disposed on the tapered portion. 10. The power storage module according to any one of clauses 1 to 9. [Explanation of symbols]

[0069] 10...electrode laminate, 11...bipolar electrode, 12...positive terminal electrode, 13...negative terminal electrode, 20...sealing body, 100...energy storage module, 200...module body, 300, 300A...terminal, 310...connecting portion, 310a...main surface (fifth surface), 320...deformation portion, 321...first flat plate portion, 321a...main surface (first surface), 322...second flat plate portion, 322a...main surface (second surface), 323...third flat plate portion, 323a... Main surface (third surface), 324...fourth flat plate portion, 324a...main surface (fourth surface), 330, 330A...protruding portion, 330a...tip, 330b...tip portion, 331...first portion, 331a, 331b...outer surface, 332...second portion, 332a, 332b, 332c, 332d...outer surface, 333...third portion, 334...side plate, 340...partition wall, 400...resin part, 410...terminal accommodating portion, 412...tapered portion, S...internal space.

Claims

1. an electrode stack having a plurality of electrodes stacked along a first direction; a sealing body that surrounds the electrode stack as viewed from the first direction and seals an internal space formed between the electrodes adjacent to each other in the first direction; a terminal provided on the electrode and extending to the outside of the sealing body; Equipped with the terminal has a connection portion connected to the electrode, a protrusion portion extending along a second direction perpendicular to the first direction and protruding to the outside of the sealing body, and a deformation portion disposed between the connection portion and the protrusion portion, the deformation portion has a first flat plate portion and a second flat plate portion connected to the first flat plate portion, the first flat plate portion has a first surface extending in the second direction and a third direction perpendicular to the first direction and the second direction, and is more easily elastically deformed in the first direction than the second flat plate portion; the second flat plate portion has a second surface extending in the first direction and the second direction, and is more easily elastically deformed in the third direction than the first flat plate portion; Energy storage module.

2. the deformation portion further includes a third flat plate portion connected to the second flat plate portion, the third flat plate portion has a third surface that extends in the first direction and is inclined in the second direction and the third direction, and is more easily elastically deformed in the third direction than the first flat plate portion; The energy storage module according to claim 1 .

3. the deformation portion further includes a fourth plate portion connected to the third plate portion, the fourth flat plate portion has a fourth surface extending in the second direction and the third direction, and is more easily elastically deformed in the third direction than the first flat plate portion; The energy storage module according to claim 2 .

4. The protrusion includes a tip portion that tapers toward the tip in the second direction. The storage module according to any one of claims 1 to 3.

5. The protrusion has a pair of flat outer surfaces facing opposite sides in a direction perpendicular to the second direction. The storage module according to any one of claims 1 to 3.

6. The connection portion has a fifth surface that is flush with the first surface. The storage module according to any one of claims 1 to 3.

7. The protrusion has a hollow structure, The terminal has a partition wall between the protruding portion and the deforming portion. The storage module according to any one of claims 1 to 3.

8. The partition wall extends in the first direction and the third direction. The electricity storage module according to claim 7 .

9. a resin part provided with a terminal accommodating portion that accommodates the protrusion, The terminal accommodating portion has a tapered portion in which the length of the terminal accommodating portion in the first direction decreases as the terminal accommodating portion becomes farther from the sealing body in the second direction. The storage module according to any one of claims 1 to 3.

10. a resin part provided with a terminal accommodating portion that accommodates the protrusion, the terminal accommodating portion has a tapered portion in which the length of the terminal accommodating portion in the first direction decreases as the terminal accommodating portion becomes farther from the electrode stack in the second direction; The protrusion has a hollow structure, the terminal has a partition wall between the protruding portion and the deforming portion, The partition wall is disposed on the tapered portion. The storage module according to any one of claims 1 to 3.

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