Electric energy storage device

Abstract

To provide a power storage device with high reliability in sealing property near a penetration hole where a conductive path between the inside and the outside of a case is formed.SOLUTION: A power storage device 100 disclosed herein includes an electrode body 20a that includes a first electrode, a case 10 that accommodates this, and a first current collector member 70 that is electrically connected to the first electrode. The case 10 includes a first wall 14 having a first penetration hole 18. The first current collector member 70 includes a first region 71 disposed along an inner surface 14b of the first wall 14. The first region 71 includes a protrusion part 72 protruding toward the first wall 14. At least a part of the protrusion part 72 is disposed in the first penetration hole 18. The first current collector member 70 includes a second region 73 beside the first region 71. Between the first region 71 and the second region 73, a first slit 74 is formed. The second region 73 is disposed along an inner surface 14b of the first wall 14 and the second region 73 faces the inner surface 14b of the first wall 14 through an insulating member 80.SELECTED DRAWING: Figure 12

Description

Technical Field

[0001] The present disclosure relates to a power storage device.

Background Art

[0002] Patent Document 1 discloses a technique related to a sealed battery. The current collector terminal provided in the sealed battery has an electrode body connection part, an external connection part, and a shaft part located between the electrode body connection part and the external connection part. The electrode body connection part is connected to an electrode body housed inside a case member. The external connection part is disposed outside the case member. The shaft part is inserted through a terminal mounting hole provided in the case member. Also, an insulating member is disposed between the current collector terminal and the terminal mounting hole. The insulating member is integrally formed with the current collector terminal and the case member. Accordingly, it is said that the electrode can be easily taken out to the outside of the case member without going through a process such as joining a plurality of terminals.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] The inventor is considering reducing the number of components constituting the conduction path from an electrode body housed inside a case of a power storage device (for example, a battery) to a terminal outside the case. At this time, the reliability of the sealing property near a through hole provided to provide a conduction path between the inside and the outside of the case can be a problem.

Means for Solving the Problems

[0005] According to the present disclosure, there is provided a power storage device including an electrode body including a first electrode and a second electrode, a case housing the electrode body, and a first current collecting member electrically connected to the first electrode. The case has a first wall, and the first wall has a first through hole. The first current collecting member has a first region disposed along the inner surface of the first wall. In the first region, a protruding portion protruding toward the first wall is provided, and at least a part of the protruding portion is disposed in the first through hole. The first current collecting member has a second region on a lateral side of the first region, and a first slit is formed between the first region and the second region. The second region is disposed along the inner surface of the first wall, and the second region faces the inner surface of the first wall via an insulating member.

[0006] According to such a configuration, since the first current collecting member is provided with the first slit, it becomes easier for the insulating member to enter the first slit, and the sealing property around the first through hole can be improved.

Brief Description of the Drawings

[0007]

Figure 1

Figure 2

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Figure 10

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Figure 12

Figure 13

Mode for Carrying Out the Invention

[0008] Hereinafter, some preferred embodiments of the technology disclosed herein will be described with reference to the drawings. Note that matters other than those specifically mentioned in this specification and necessary for the implementation of the present disclosure (for example, general configurations and manufacturing processes of batteries that do not characterize the present disclosure) can be grasped as design matters of those skilled in the art based on the prior art in the relevant field. The present disclosure can be implemented based on the content disclosed in this specification and common general knowledge in the relevant field. In this specification, the notation "A to B (where A and B are arbitrary numerical values)" indicating a range means "A or more and B or less", and also includes the meanings of "more than A and less than B", "more than A and B or less", and "A or more and less than B".

[0009] In this specification, the "power storage device" refers to a device that can perform charging and discharging. Power storage devices include batteries such as primary batteries and secondary batteries (for example, lithium ion secondary batteries and nickel metal hydride batteries), and capacitors (physical batteries) such as electric double layer capacitors. Hereinafter, the present technology will be described by taking a lithium ion secondary battery, which is an embodiment of the power storage device disclosed herein, as an example.

[0010] FIG. 1 is a perspective view schematically showing the configuration of a power storage device 100 (hereinafter also referred to as battery 100). FIG. 2 is a longitudinal sectional view schematically showing the configuration of battery 100. FIG. 3 is a sectional view taken along line III-III in FIG. 2. FIG. 4 is a sectional view taken along line IV-IV in FIG. 2. In the following description, the symbols L, R, F, Rr, U, and D in the drawings represent left, right, front, rear, up, and down, respectively, and the symbols X, Y, and Z in the drawings represent the short side direction, the long side direction orthogonal to the short side direction, and the up-down direction of battery 100, respectively. However, these are merely directions for convenience of explanation and do not limit the installation form of battery 100 in any way.

[0011] As shown in FIG. 2, the battery 100 according to the present embodiment includes a case 10, an electrode body group 20, a positive electrode terminal member 30, a negative electrode terminal member 40, a positive electrode current collector 50, a negative electrode current collector 60, and an insulating member 80. Although not shown, the battery 100 according to the present embodiment further includes an electrolytic solution. The electrode body 20a included in the electrode body group 20 includes a first electrode and a second electrode. The first electrode can be a positive electrode or a negative electrode, but in the present embodiment, the first electrode is a positive electrode. Also, the second electrode is a positive electrode or a negative electrode and is an electrode different from the first electrode. In the present embodiment, the second electrode is a negative electrode.

[0012] The case 10 is a housing that houses one or two or more electrode bodies (here, the electrode body group 20). The case 10 has a flat and bottomed rectangular parallelepiped shape (rectangular shape) here. The material of the case 10 may be the same as those conventionally used and is not particularly limited. The case 10 is preferably made of a metal having a predetermined strength and can be composed of, for example, aluminum, an aluminum alloy, iron, an iron alloy, or the like. Note that the shape of the case 10 is not limited to a rectangular shape and may be cylindrical or polyhedral.

[0013] Case 10 is in the shape of a hexahedron having six walls here. As shown in FIG. 1, case 10 includes a first wall 14 as an upper wall, a substantially rectangular bottom wall 12a facing the first wall 14, a pair of first side walls 12b extending upward U from the short sides of the bottom wall 12a and facing each other, and a pair of second side walls 12c extending upward U from the long sides of the bottom wall 12a and facing each other. The first wall 14 is formed in a substantially rectangular shape here. The area of the second side wall 12c is smaller than the area of the first side wall 12b. In the present embodiment, case 10 includes an exterior body 12 including the bottom wall 12a, the first side walls 12b, and the second side walls 12c, and a sealing plate (hereinafter also referred to as sealing plate 14) as the first wall 14. Note that the first wall is not limited to the sealing plate 14 and may be any of the walls included in case 10.

[0014] The exterior body 12 is a flat rectangular (hexahedron shape) container with one face being an opening 12h. The opening 12h is formed on the upper surface of the exterior body 12 surrounded by the pair of first side walls 12b and the pair of second side walls 12c. The sealing plate 14 is attached to the exterior body 12 so as to close the opening 12h of the exterior body 12. The sealing plate 14 is a plate material having a substantially rectangular shape in plan view. Case 10 is formed by joining (for example, welding) the sealing plate 14 to the peripheral edge of the opening 12h of the exterior body 12. The joining of the sealing plate 14 can be performed by welding such as laser welding.

[0015] As shown in FIGS. 1 and 2, a gas discharge valve 17 is provided on the sealing plate 14. The gas discharge valve 17 is configured to open when the pressure in case 10 reaches a predetermined value or more and discharge the gas in case 10.

[0016] In addition to the gas discharge valve 17, the sealing plate 14 is provided with a liquid injection hole 15, a first through hole 18, and a second through hole 19. The liquid injection hole 15 communicates with the internal space of the case 10 and is an opening provided for injecting electrolyte during the manufacturing process of the battery 100. The liquid injection hole 15 is sealed by a sealing member 16. As such a sealing member 16, for example, a blind rivet is suitable. Thereby, the sealing member 16 can be firmly fixed inside the case 10.

[0017] The first through hole 18 has a size that allows a part of the positive electrode terminal member 30 or the positive electrode current collector 50 to be inserted, and its shape is not particularly limited. For example, in a plan view, the first through hole 18 can be circular, elliptical, square, rectangular (such as a square or rectangle), polygonal, or the like. Also, the corners of the first through hole 18 may be R-processed. Here, the first through hole 18 is provided so as to be rectangular with R-processed corners in a plan view. The second through hole 19 is not particularly limited as long as it has a size that allows a part of the negative electrode terminal member 40 or the negative electrode current collector 60 to be inserted. The shape of the second through hole 19 may be the same as that of the first through hole 18.

[0018] FIG. 5 is a perspective view schematically showing the electrode body group 20 attached to the sealing plate 14. In the present embodiment, a plurality (here, three) of electrode bodies 20a, 20b, and 20c are accommodated inside the case 10. The number of electrode bodies accommodated inside one case 10 is not particularly limited and may be one or two or more (a plurality). As shown in FIG. 2, the positive electrode current collector 50 is arranged on one side (the left side in FIG. 2) in the long side direction Y of each electrode body, and the negative electrode current collector 60 is arranged on the other side (the right side in FIG. 2) in the long side direction Y. And each of the electrode bodies 20a, 20b, and 20c is connected in parallel. However, the electrode bodies 20a, 20b, and 20c may be connected in series. The electrode body group 20 is accommodated inside the case 10 in a state covered with an electrode body holder 29 made of a resin sheet here.

[0019] FIG. 6 is a perspective view schematically showing an electrode body 20a to which a second positive electrode current collector 52 and a second negative electrode current collector 62 are attached. FIG. 7 is a schematic view showing the configuration of the electrode body 20a. Hereinafter, the electrode body 20a will be described in detail as an example, but the electrode bodies 20b and 20c can have the same configuration.

[0020] As shown in FIG. 7, the electrode body 20a has a positive electrode 22, a negative electrode 24, and a separator 26. Here, the electrode body 20a is a wound electrode body in which a strip-shaped positive electrode 22 and a strip-shaped negative electrode 24 are laminated via two strip-shaped separators 26 and wound around a winding axis WL. However, the structure of the electrode body is not limited to the technology disclosed herein. For example, the electrode body may be a laminated electrode body in which a plurality of rectangular (typically rectangular) positive electrodes and a plurality of rectangular (typically rectangular) negative electrodes are stacked in an insulated state.

[0021] In the present embodiment, the electrode body 20a has a flat shape. The electrode body 20a is disposed inside the exterior body 12 in a direction in which the winding axis WL is substantially parallel to the long side direction Y. Specifically, as shown in FIG. 3, the electrode body 20a has a pair of curved portions (R portions) 20r facing the bottom wall 12a and the sealing plate 14 of the exterior body 12, and a flat portion 20f that connects the pair of curved portions 20r and faces the first side wall 12b of the exterior body 12. The flat portion 20f extends along the first side wall 12b.

[0022] As shown in FIG. 7, the positive electrode 22 has a positive electrode current collector 22c and a positive electrode active material layer 22a fixed on at least one surface of the positive electrode current collector 22c. The positive electrode 22 may have a positive electrode protective layer 22p. Here, the positive electrode current collector 22c is strip-shaped. The positive electrode current collector 22c is made of a conductive metal such as aluminum, an aluminum alloy, nickel, or stainless steel. The positive electrode current collector 22c is, for example, a metal foil, and here it is an aluminum foil.

[0023] At one end (the left end in FIG. 7) of the positive electrode current collector 22c in the long side direction Y, a plurality of positive electrode tabs 22t are provided. The plurality of positive electrode tabs 22t are provided at intervals (intermittently) along the longitudinal direction of the strip-shaped positive electrode 22. The plurality of positive electrode tabs 22t protrude outward from the separator 26 toward one side (the left side in FIG. 7) in the axial direction of the winding axis WL. Note that the positive electrode tab 22t may be provided on the other side (the right side in FIG. 7) in the axial direction of the winding axis WL, or may be provided on each of both sides in the axial direction of the winding axis WL. The positive electrode tab 22t is a part of the positive electrode current collector 22c and is made of a metal foil (aluminum foil). However, the positive electrode tab 22t may be a member different from the positive electrode current collector 22c. In at least a part of the positive electrode tab 22t, a region where the positive electrode current collector 22c is exposed is formed without forming the positive electrode active material layer 22a and the positive electrode protective layer 22p.

[0024] As shown in FIG. 4, the plurality of positive electrode tabs 22t are laminated at one end (the left end in FIG. 4) in the axial direction of the winding axis WL to form a positive electrode tab group 23. Each of the plurality of positive electrode tabs 22t is connected to the positive electrode current collecting portion 50 in a bent state. Thereby, since the size of the main body portion of the electrode body group 20 accommodated in the case 10 can be increased, the battery 100 can be made to have a higher energy density. As shown in FIG. 2, the positive electrode tab group 23 is electrically connected to the positive electrode current collecting portion 50. Here, the positive electrode tab group 23 and the second positive electrode current collecting portion 52 described later are connected at the connection portion J (see FIG. 4). The sizes of the plurality of positive electrode tabs 22t (the length in the long side direction Y and the width orthogonal to the long side direction Y, see FIG. 7) can be appropriately adjusted depending on, for example, the formation position and the like in consideration of the state of being connected to the positive electrode current collecting portion 50. The plurality of positive electrode tabs 22t have different sizes here so that the outer ends are aligned when bent. Note that the sizes of each of the positive electrode tabs may be the same. Also, the positive electrode tab 22t is trapezoidal, but may have other shapes (for example, rectangular shape, etc.).

[0025] As shown in FIG. 7, the positive electrode active material layer 22a is provided in a strip shape along the longitudinal direction of the strip-shaped positive electrode current collector 22c. The positive electrode active material layer 22a contains a positive electrode active material (for example, a lithium transition metal composite oxide such as lithium nickel cobalt manganese composite oxide) that can reversibly occlude and release charge carriers. When the total solid content of the positive electrode active material layer 22a is 100% by mass, the positive electrode active material may generally occupy 80% by mass or more, typically 90% by mass or more, for example 95% by mass or more. The positive electrode active material layer 22a may contain optional components other than the positive electrode active material, such as a conductive material, a binder, and various additive components. As the conductive material, for example, a carbon material such as acetylene black (AB) can be used. As the binder, for example, polyvinylidene fluoride (PVdF) or the like can be used.

[0026] As shown in FIG. 7, the positive electrode protective layer 22p is provided at the boundary portion between the positive electrode current collector 22c and the positive electrode active material layer 22a in the long side direction Y. Here, the positive electrode protective layer 22p is provided at one end (the left end in FIG. 7) in the axial direction of the winding axis WL of the positive electrode current collector 22c. However, the positive electrode protective layer 22p may be provided at both ends in the axial direction. The positive electrode protective layer 22p is provided in a strip shape along the positive electrode active material layer 22a. The positive electrode protective layer 22p contains an inorganic filler (for example, alumina). When the total solid content of the positive electrode protective layer 22p is 100% by mass, the inorganic filler may generally occupy 50% by mass or more, typically 70% by mass or more, for example 80% by mass or more. The positive electrode protective layer 22p may contain optional components other than the inorganic filler, such as a conductive material, a binder, and various additive components. The conductive material and the binder may be the same as those exemplified as being contained in the positive electrode active material layer 22a.

[0027] As shown in FIG. 7, the negative electrode 24 has a negative electrode current collector 24c and a negative electrode active material layer 24a fixed on at least one surface of the negative electrode current collector 24c. The negative electrode current collector 24c is strip-shaped. The negative electrode current collector 24c is made of a conductive metal such as, for example, copper, a copper alloy, nickel, or stainless steel. The negative electrode current collector 24c is, for example, a metal foil, and here it is a copper foil.

[0028] At one end in the axial direction of the winding axis WL of the negative electrode current collector 24c (the right end in FIG. 7), a plurality of negative electrode tabs 24t are provided. The plurality of negative electrode tabs 24t are provided at intervals (intermittently) along the longitudinal direction of the strip-shaped negative electrode 24. Each of the plurality of negative electrode tabs 24t protrudes outward from the separator 26 toward one side in the axial direction (the right side in FIG. 7). However, the negative electrode tab 24t may be provided at the other end in the axial direction (the left end in FIG. 7), or may be provided at each of both ends in the axial direction. The negative electrode tab 24t is a part of the negative electrode current collector 24c and is made of a metal foil (copper foil). However, the negative electrode tab 24t may be a member different from the negative electrode current collector 24c. At least a part of the negative electrode tab 24t is provided with a region where the negative electrode current collector 24c is exposed without the formation of the negative electrode active material layer 24a.

[0029] As shown in FIG. 4, the plurality of negative electrode tabs 24t are laminated at one end in the axial direction (the right end in FIG. 4) to form a negative electrode tab group 25. The negative electrode tab group 25 is preferably provided at a position symmetric to the positive electrode tab group 23 in the axial direction. And each of the plurality of negative electrode tabs 24t is connected to the negative electrode current collecting portion 60 in a bent state. Thereby, since the size of the main body portion of the electrode body group 20 accommodated in the case 10 can be increased, the battery 100 can be made to have a higher energy density. As shown in FIG. 2, the negative electrode tab group 25 is electrically connected to the negative electrode current collecting portion 60. Here, the negative electrode tab group 25 and the negative electrode second current collecting portion 62 described later are connected at the connection portion J (see FIG. 4). Similar to the plurality of positive electrode tabs 22t, here, the sizes of the plurality of negative electrode tabs 24t are different from each other so that the outer ends when bent are aligned. Note that the technology disclosed here can also be applied to the case where the sizes of the negative electrode tabs are the same. Also, the negative electrode tab 24t is trapezoidal, but may have other shapes (for example, rectangular shape, etc.).

[0030] As shown in FIG. 7, the negative electrode active material layer 24a is provided in a strip shape along the longitudinal direction of the strip-shaped negative electrode current collector 24c. The negative electrode active material layer 24a contains a negative electrode active material (for example, a carbon material such as graphite) that can reversibly occlude and release charge carriers. When the total solid content of the negative electrode active material layer 24a is 100% by mass, the negative electrode active material may account for generally 80% by mass or more, typically 90% by mass or more, for example 95% by mass or more. The negative electrode active material layer 24a may contain optional components other than the negative electrode active material, such as a binder, a dispersant, and various additive components. As the binder, for example, rubbers such as styrene-butadiene rubber (SBR) can be used. As the dispersant, for example, celluloses such as carboxymethyl cellulose (CMC) can be used.

[0031] As shown in FIG. 7, the separator 26 is a member that insulates the positive electrode active material layer 22a of the positive electrode 22 and the negative electrode active material layer 24a of the negative electrode 24. As the separator 26, for example, a porous sheet made of a polyolefin resin such as polyethylene (PE) or polypropylene (PP) is suitable. The separator 26 may have a base material portion made of a porous sheet made of resin and a heat resistance layer (HRL) provided on at least one surface of the base material portion and containing an inorganic filler. As the inorganic filler, for example, alumina, boehmite, aluminum hydroxide, titania, etc. can be used.

[0032] The electrolytic solution may be the same as the conventional one and is not particularly limited. The electrolytic solution is, for example, a non-aqueous electrolytic solution containing a non-aqueous solvent and a supporting salt. The non-aqueous solvent contains, for example, carbonates such as ethylene carbonate, dimethyl carbonate, and ethyl methyl carbonate. The supporting salt is, for example, a fluorine-containing lithium salt such as LiPF6. However, the electrolytic solution may be in a solid state (solid electrolyte) and integrated with the electrode body group 20.

[0033] The positive electrode current collector 50 constitutes at least a part of the conduction path from the positive electrode tab group 23 composed of a plurality of positive electrode tabs 22t to the outside of the case 10. In the present embodiment, as shown in FIG. 2, the positive electrode current collector 50 includes a first positive electrode current collector 51 and a second positive electrode current collector 52. Note that the positive electrode current collector 50 may not be composed of a plurality of members as in the present embodiment, and may be composed of one member.

[0034] In the present embodiment, as the first positive electrode current collector 51, the first current collector member 70 disclosed here is adopted. The configuration of the first current collector member 70 will be described later.

[0035] The second positive electrode current collector 52 extends along the second side wall 12c of the exterior body 12. In the present embodiment, as shown in FIG. 6, the second positive electrode current collector 52 is configured in a plate shape extending along the vertical direction Z. The second positive electrode current collector 52 has an inclined portion in the middle of its extension in the vertical direction Z. One end of the second positive electrode current collector is joined to the first positive electrode current collector 51, and the other end is joined to the positive electrode tab group 23. These joints can be realized by welding such as ultrasonic welding, resistance welding, laser welding, etc., respectively. The second positive electrode current collector 52 can be composed of, for example, the same metal species as the positive electrode current collector 22c, and can be composed of a conductive metal such as aluminum, aluminum alloy, nickel, stainless steel, etc.

[0036] As shown in FIGS. 1 and 2, at least a part of the positive electrode terminal member 30 is arranged so as to be exposed outside the case 10. By being electrically connected to the positive electrode current collector 50, the positive electrode terminal member 30 can extend the conduction path and improve the connectivity with an external member (for example, a bus bar). In the present embodiment, as shown in FIG. 2, inside the first through hole 18 provided in the sealing plate 14, the positive electrode terminal member 30 is electrically connected to the first positive electrode current collector 51. Also, the upper surface 30a of the positive electrode terminal member 30 is arranged outside the case 10 and can serve as a joint surface with an external member. The positive electrode terminal member 30 is preferably made of metal and can be composed of, for example, aluminum, aluminum alloy, nickel, stainless steel, etc.

[0037] The negative electrode current collector 60 constitutes at least a part of the conduction path from the negative electrode tab group 25 composed of a plurality of negative electrode tabs 24t to the outside of the case 10. In the present embodiment, as shown in FIG. 2, the negative electrode current collector 60 includes a first negative electrode current collector 61 and a second negative electrode current collector 62. Note that the negative electrode current collector 60 may not be composed of a plurality of members as in the present embodiment, and may be composed of one member. In the present embodiment, as the first negative electrode current collector 61, the first current collector member 70 disclosed herein is adopted.

[0038] The second negative electrode current collector 62 extends along the second side wall 12c of the exterior body 12. In the present embodiment, as shown in FIG. 6, the second negative electrode current collector 62 is configured in a plate shape extending along the vertical direction Z. The second negative electrode current collector 62 has an inclined portion in the middle of extending in the vertical direction Z. One end of the second negative electrode current collector 62 is joined to the first negative electrode current collector 61, and the other end is joined to the negative electrode tab group 25. These joints can be realized by welding such as ultrasonic welding, resistance welding, laser welding, etc. respectively. The second negative electrode current collector 62 can be composed of, for example, the same metal type as the negative electrode current collector 24c, and can be composed of a conductive metal such as copper, copper alloy, nickel, stainless steel, etc.

[0039] As shown in FIGS. 1 and 2, the negative electrode terminal member 40 is arranged such that at least a part thereof is exposed to the outside of the case 10. By being electrically connected to the negative electrode current collector 60, the negative electrode terminal member 40 can extend the conduction path and improve the connectivity with an external member (for example, a bus bar). In the present embodiment, as shown in FIG. 2, the negative electrode terminal member 40 is electrically connected to the first negative electrode current collector 61 inside the second through hole 19 provided in the sealing plate 14. The negative electrode terminal member 40 is preferably made of metal, and more preferably made of copper or a copper alloy, for example.

[0040] The first current collector member 70 disclosed herein will be described below. The first current collector member 70 is a member that is electrically connected to at least one of the first electrode and the second electrode. In the following description, an embodiment in which the first current collector member 70 is electrically connected to the positive electrode as the first electrode will be described in detail as an example. Note that the first current collector member 70 can also be adopted for the negative electrode, and its structure can be understood, for example, by reading the positive electrode as the negative electrode in the following description.

[0041] FIG. 8 is a perspective view schematically showing an embodiment of the configuration of the first current collector member disclosed herein. FIG. 9 is a perspective view schematically showing the configuration in the vicinity of the first through hole near the sealing plate to which the first current collector member is attached. FIG. 10 is a perspective view of the configuration in the vicinity of the first through hole of the sealing plate to which the first current collector member shown in FIG. 9 is attached, as viewed from the inner surface side of the sealing plate. FIG. 11 is a cross-sectional view taken along line XI-XI of FIG. 9. FIG. 12 is a cross-sectional view taken along line XII-XII of FIG. 9.

[0042] As shown in FIG. 8, the first current collector member 70 has a first region 71, a second region 73, and a first slit 74 formed between the first region 71 and the second region 73. Further, in the present embodiment, the first current collector member 70 further has a third region 75, a second slit 76 formed between the first region 71 and the third region 75, a fourth region 77, and a fifth region 78.

[0043] The first region 71 is a region arranged along the inner surface 14b of the first wall (here, the sealing plate 14) of the case 10. The upper surface 71a of the first current collecting member 70 in the first region 71 faces the inner surface 14b of the sealing plate 14. Here, the first region 71 extends in the longitudinal direction (long side direction Y) of the sealing plate 14. The first region 71 is provided with a base portion 71c and a protruding portion 72 protruding from the base portion 71c. The protruding portion 72 protrudes toward the first wall (sealing plate 14). In the present embodiment, the protruding portion 72 has an upper surface 72a (tip surface). Further, the protruding portion 72 has a lower surface 72b facing the upper surface 72a. Note that the tip of the protruding portion 72 does not necessarily have to have an upper surface. In the present embodiment, the base portions 71c are arranged on both sides of the protruding portion 72 in the long side direction Y.

[0044] In the first region 71, the first current collecting member 70 is configured in a plate shape in the present embodiment. The protruding portion 72 is configured to be bent so that the plate-shaped first current collecting member 70 protrudes toward the upper surface 71a side. Accordingly, a concave portion 71d corresponding to the shape of the protruding portion 72 is provided on the lower surface 71b of the first current collecting member 70 in the first region 71. The bottom surface of such a concave portion 71d is the lower surface 72b of the protruding portion 72. Here, since the plate-shaped first current collecting member 70 is bent to form the protruding portion 72, the average thickness of the first current collecting member 70 on the upper surface 72a of the protruding portion 72 and the average thickness of the first current collecting member 70 on the base portion 71c are substantially the same. For example, when the average thickness of the first current collecting member 70 on the base portion 71c is set to 100%, the average thickness of the first current collecting member 70 on the upper surface 72a of the protruding portion 72 can be 90% - 110%, or 95% - 105%. Thus, by forming the protruding portion 72 by bending the plate-shaped member, the protruding portion 72 becomes lighter compared to a structure having a solid axis, so that the weight of the battery 100 can be reduced, which is preferable. However, the configuration of the protruding portion 72 is not limited to this, and it may be configured with a solid axis or a hollow axis. Note that the average thickness of the first current collecting member 70 can be measured by, for example, a reflection type laser displacement meter or the like.

[0045] The length of the first region 71 in the longitudinal direction (direction Y) of the sealing plate 14 is preferably greater than the longest length of the first through hole 18 in the longitudinal direction. Thereby, since an insulating member 80 described later disposed between the first region 71 and the sealing plate 14 can be disposed on both sides in the longitudinal direction of the first through hole 18, the sealing property in the vicinity of the first through hole 18 can be improved.

[0046] The second region 73 is a region disposed along the inner surface 14b of the first wall (here, the sealing plate 14) of the case 10, similarly to the first region 71. The second region 73 is a region disposed on the lateral side of the first region 71. In other words, the second region 73 is disposed at a position shifted from the first region 71 in a plane parallel to the inner surface 14b of the first wall (sealing plate 14) (for example, a position shifted from the base portion 71c). Here, the second region 73 is disposed on one side in the short side direction X of the battery 100 of the first region 71. Note that the second region 73 may be disposed on one side in the long side direction Y of the battery 100 of the first region 71. Here, the second region 73 extends in the longitudinal direction (long side direction Y) of the first wall (sealing plate 14). In the present embodiment, the first current collecting member 70 in the second region 73 is configured in a plate shape.

[0047] The first slit 74 is formed between the first region 71 and the second region 73. In the present embodiment, the first slit 74 is formed in a substantially rectangular shape in plan view. Here, in plan view, the distance between the first region 71 and the second region 73 is the short side, and the direction perpendicular to the short side is the long side of a substantially rectangular shape. Since the first current collecting member 70 has the first slit 74, an insulating member 80 described later can easily enter the first slit 74, and the sealing property of the periphery of the first through hole 18 can be improved.

[0048] In the present embodiment, the length of the first slit 74 in the longitudinal direction (direction Y) of the sealing plate 14 is longer than the longest length of the first through hole 18 in the longitudinal direction. Further, the first slit 74 is disposed so as to extend across both ends of the first through hole 18 in the longitudinal direction. Thereby, the sealing property of the periphery of the first through hole 18 can be further improved.

[0049] The third region 75 is a region arranged along the inner surface 14b of the first wall (here, the sealing plate 14) of the case 10. The third region 75 is a region arranged laterally of the first region 71. Here, the third region 75 is arranged on the opposite side of the second region 73 with respect to the first region 71. That is, the first region 71 is arranged between the second region 73 and the third region 75. Here, the third region 75 is arranged on one side in the short side direction X of the battery 100 in the first region 71. Note that the third region 75 may be arranged on one side in the long side direction Y of the battery 100 in the first region 71. Here, the third region 75 extends in the longitudinal direction (long side direction Y) of the first wall (sealing plate 14). In the present embodiment, the first current collecting member 70 in the third region 75 is configured in a plate shape. Note that the third region 75 is not an essential configuration.

[0050] The second slit 76 is formed between the first region 71 and the third region 75. In the present embodiment, the second slit 76 is formed in a rectangular shape in a plan view. Here, in the plan view, it has a rectangular shape with the distance between the first region 71 and the third region 75 as the short side and the direction perpendicular to the short side as the long side. By the first current collecting member 70 having the second slit 76, the insulating member 80 described later can easily enter the second slit 76, and the sealing property around the first through hole 18 can be improved. By the first current collecting member 70 having the first slit 74 and the second slit 76, the sealing property is improved at both ends of the first through hole 18, so that a battery 100 with higher sealing reliability can be realized. Note that the second slit 76 is not an essential configuration.

[0051] In the present embodiment, the length of the second slit 76 in the longitudinal direction (direction Y) of the sealing plate 14 is longer than the longest length of the first through hole 18 in the long side direction. Further, the second slit 76 is arranged so as to extend across both ends of the first through hole 18 in the long side direction. Thereby, the sealing property around the first through hole 18 can be further improved.

[0052] As shown in FIG. 8, in the present embodiment, the fourth region 77 is a region extending in the vertical direction Z. The fourth region 77 is a region extending from the side of the sealing plate 14 toward the bottom wall 12a side of the case 10. The fourth region 77 is disposed, for example, along the first side wall 12b or the second side wall 12c of the case 10. In the present embodiment, the fourth region 77 is disposed along the second side wall 12c. Here, the fourth region 77 is electrically connected to the second positive current collector portion 52. Thereby, conduction to the first current collector member 70 is realized. Note that the fourth region 77 may be directly joined to the positive electrode tab group 23. Thereby, the number of components of the conduction path can be reduced, and cost reduction can be achieved. Such joining can be realized, for example, by welding such as ultrasonic welding, resistance welding, or laser welding. In the present embodiment, the first current collector member 70 in the fourth region 77 is formed in a plate shape. Note that the fourth region 77 is not an essential configuration in the present technology.

[0053] The fifth region 78 is a region connecting the first region 71 and the fourth region 77. Here, as shown in FIG. 8, the fifth region 78 is disposed between the first region 71 and the fourth region. The fifth region 78 is disposed continuously with the first region 71. Here, the fifth region is disposed so as to be continuous with the fourth region 77. In the present embodiment, the fifth region 78 is also located between the second region 73 and the fourth region 77 and is disposed continuously with the second region 73. Further, the fifth region 78 is also located between the third region 75 and the fourth region 77 and is disposed continuously with the third region 75. The fifth region 78 is disposed along the inner surface 14b of the first wall (here, the sealing plate 14) of the case 10. In the fifth region 78, the first current collector member 70 is formed in a plate shape here. Note that the fifth region 78 is not an essential configuration in the present technology. For example, the fourth region 77 and the first region 71 may be connected. Further, the second region 73 and / or the third region 75 may be connected to the fourth region 77.

[0054] The first current collector member 70 can be made of, for example, metal. Examples of such metal include aluminum, aluminum alloy, copper, copper alloy, and the like.

[0055] The first current collecting member 70 preferably has a substantially constant thickness throughout. For example, when the average thickness of the first current collecting member 70 is taken as 100%, the maximum thickness of the first current collecting member 70 is preferably 120% or less, more preferably 110% or less, and even more preferably 105% or less. Also, the minimum thickness of the first current collecting member 70 is preferably 80% or more, more preferably 90% or more, and even more preferably 95% or more.

[0056] The first current collecting member 70 can be easily manufactured, for example, by bending, punching, etc. of a single plate-shaped material (e.g., a metal plate). Thereby, the first current collecting member 70 having a substantially constant thickness throughout can be realized.

[0057] At least a part of the protruding portion 72 of the first current collecting member 70 is disposed inside the first through hole 18 provided in the sealing plate 14 (see FIGS. 11 and 12). Here, the upper surface 72a, which is the upper end (tip) of the protruding portion 72, is disposed inside the first through hole 18. In the present embodiment, the upper surface 72a of the protruding portion 72 is connected to the lower surface 30b of the positive electrode terminal member 30 inside the first through hole 18. The connection method between the positive electrode terminal member 30 and the first current collecting member 70 is not particularly limited, and examples include caulking, ultrasonic bonding, resistance welding, laser welding, pressure welding, etc., and one of these can be selected or a plurality can be combined and implemented. Note that the positive electrode terminal member 30 is not an essential configuration in the present technology. Also, in the present embodiment, the lower surface 72b of the protruding portion 72 is disposed inside the case 10 rather than inside the first through hole 18. However, the lower surface 72b of the protruding portion 72 may be disposed inside the first through hole 18.

[0058] As shown in FIGS. 9 to 12, the insulating member 80 insulates the first current collecting member 70 from the case 10 (here, the sealing plate 14). Also, here, the insulating member 80 insulates the positive terminal member 30 from the case 10 (here, the sealing plate 14). In the present embodiment, the insulating member 80 includes a first insulating portion 82 disposed inside the case 10, a second insulating portion 84 disposed inside the first through hole 18, and a third insulating portion 86 disposed outside the case 10.

[0059] As shown in FIGS. 10 to 12, the first insulating portion 82 is disposed along the inner surface 14b of the sealing plate 14. The first insulating portion 82 is disposed inside the case 10 between the region of the first current collecting member 70 facing the sealing plate 14 and the inner surface 14b of the sealing plate 14. Here, the second region 73 of the first current collecting member 70 is disposed to face the inner surface 14b of the sealing plate 14 with the first insulating portion 82 therebetween. Also, in the present embodiment, the third region 75 and the fifth region 78 of the first current collecting member 70 are similarly disposed to face the inner surface 14b of the sealing plate 14 with the first insulating portion 82 therebetween. Further, the portion of the first region 71 of the first current collecting member 70 disposed inside the case 10 is disposed to face the inner surface 14b of the sealing plate 14 with the first insulating portion 82 therebetween.

[0060] The first insulating portion 82 is preferably disposed without a gap between the region of the first current collecting member 70 facing the sealing plate 14 and the inner surface 14b of the sealing plate 14. Thereby, the sealing performance of the peripheral portion of the first through hole 18 can be further improved.

[0061] At least a part of the first insulating portion 82 is preferably disposed inside the first slit 74 of the first current collector member 70 (see FIG. 10). Thereby, since the first current collector member 70 and the first insulating portion 82 are more closely adhered, the sealing property in the vicinity of the first through hole 18 can be improved. In the present embodiment, the first insulating portion 82 is disposed on the side of the sealing plate 14 inside the first slit 74, and the first insulating portion 82 is not disposed at the end on the side of the electrode body group 20 inside the first slit 74. Such a configuration is advantageous from the viewpoint of reducing the weight of the battery 100. However, the first insulating portion 82 may be disposed throughout the inside of the first slit 74. Such a configuration is advantageous from the viewpoint of improving the sealing property.

[0062] At least a part of the first insulating portion 82 is preferably disposed inside the second slit 76 of the first current collector member 70 (see FIG. 10). Thereby, since the first current collector member 70 and the first insulating portion 82 are more closely adhered, the sealing property in the vicinity of the first through hole 18 can be improved. In the present embodiment, the first insulating portion 82 is disposed on the side of the sealing plate 14 inside the second slit 76, and the first insulating portion 82 is not disposed at the end on the side of the electrode body group 20 inside the second slit 76. Such a configuration is advantageous from the viewpoint of reducing the weight of the battery 100. However, the first insulating portion 82 may be disposed throughout the inside of the second slit 76. Such a configuration is advantageous from the viewpoint of improving the sealing property.

[0063] At least a part of the first insulating portion 82 is preferably disposed on the side of the electrode body group 20 (the lower surface 72b side of the protruding portion 72) of the protruding portion 72 of the first current collector member 70. Here, the protruding portion 72 and the first insulating portion 82 are disposed so as to be in contact with each other. Thereby, the sealing property in the vicinity of the first through hole 18 can be improved. Further, the first insulating portion 82 is preferably bridged so as to pass through the side of the electrode body group 20 of the protruding portion 72. In the present embodiment, the first insulating portion 82 bridges the side of the electrode body group 20 (the concave portion 71d) of the protruding portion 72 at two locations in the short side direction of the sealing plate 14. Thereby, the first current collector member 70 and the insulating member 80 are more closely adhered, and the sealing property can be improved. The number of bridges is not particularly limited, and may be one or a plurality of two or more.

[0064] The first insulating portion 82 disposed on the electrode body group 20 side of the protruding portion 72 is preferably not disposed on the lower surface 71b side of the base portion 71c of the first region 71. In other words, it is preferable that the lower surface 71b of the base portion 71c is exposed. Thereby, the space occupied by the electrode body group 20 can be expanded inside the case 10. Here, on the lower surface 71b of the first region 71, the first insulating portion 82 is disposed only in the recess 71d on the electrode body group 20 side of the protruding portion 72.

[0065] The first insulating portion 82 may have a through hole 82a penetrating from the electrode body group 20 side toward the lower surface of the protruding portion 72 at a position on the electrode body group 20 side of the protruding portion 72. As shown in FIG. 10, when viewed from the inner surface 14b side of the sealing plate 14, the lower surface 72b of the protruding portion 72 is exposed in such a through hole 82a. Such a through hole 82a can be formed, for example, in a manufacturing process described later.

[0066] In the second region 73, the first insulating portion 82 is preferably not disposed on the surface (lower surface) on the electrode body group 20 side of the first current collecting member 70, and the lower surface is exposed. Further, in the third region 75, the first insulating portion 82 is preferably not disposed on the surface (lower surface) on the electrode body group 20 side of the first current collecting member 70, and the lower surface is exposed. Thereby, the space occupied by the electrode body group 20 can be expanded inside the case 10.

[0067] The first insulating portion 82 is preferably disposed over the peripheral portion of the first through hole 18. Thereby, the sealing property in the vicinity of the first through hole 18 can be improved. Further, the first insulating portion 82 is preferably disposed over the periphery of the region facing the sealing plate 14 of the first current collecting member 70. In the present embodiment, the first insulating portion 82 extends outside the first region 71, the second region 73, and the third region 75 in the longitudinal direction (direction Y) of the sealing plate 14, and is disposed to extend outside the fourth region 77. Also, in the short-side direction (direction X) of the sealing plate 14, the first insulating portion 82 is disposed to extend outside the second region 73 and to extend outside the third region 75. Further, as shown in FIGS. 11 and 12, the thickness of the first insulating portion 82 around the region facing the sealing plate 14 of the first current collecting member 70 may be larger than the thickness of the first insulating portion 82 disposed between the first current collecting member 70 and the sealing plate 14. The first insulating portion 82 may be disposed so as to contact not only the surface of the first current collecting member 70 facing the sealing plate 14 inside the case 10 but also the side surface of the first current collecting member 70 extending in the thickness direction of the first current collecting member 70. Thereby, the adhesion between the first current collecting member 70 and the first insulating portion 82 is improved, and the sealing property can be further improved.

[0068] As shown in FIG. 2, the first insulating portion 82 may include a movement restricting portion 82b for restricting the movement of the electrode body group 20 toward the sealing plate 14 side. In FIG. 2, as the movement restricting portion 82b, the end portion of the first insulating portion 82 protrudes toward the electrode body group 20 side.

[0069] The second insulating portion 84 is disposed between the inner surface 18a of the first through hole 18 and the first current collecting member 70 disposed inside the first through hole 18, and insulates the first current collecting member 70 and the sealing plate 14. Here, the second insulating portion is also disposed between the inner surface 18a of the first through hole 18 and the positive electrode terminal member 30 disposed inside the first through hole 18, and insulates the positive electrode terminal member 30 and the sealing plate 14.

[0070] The second insulating portion 84 is preferably arranged so as to close the first through hole 18. As shown in FIGS. 11 and 12, in this embodiment, the first through hole 18 is closed by the second insulating portion 84 and the upper end of the protruding portion 72. Thereby, the sealing performance is improved. When at least a part of the recess 71d in the first region 71 of the first current collecting member 70 is arranged in the first through hole 18, the second insulating portion 84 may be arranged in such a recess 71d.

[0071] The third insulating portion 86 is a portion continuous with the second insulating portion 84 and is arranged outside the case 10. Here, the third insulating portion 86 is arranged along the periphery of the positive electrode terminal member 30 outside the case 10. The third insulating portion 86 preferably contacts the peripheral region of the first through hole 18 on the outer surface 14a of the sealing plate 14 (the first wall). Here, in a plan view, the peripheral edge portion of the third insulating portion 86 is arranged outside the first through hole 18, and the peripheral edge portion contacts the outer surface 14a of the sealing plate 14. Thereby, the sealing performance in the vicinity of the first through hole 18 can be improved. Note that the insulating member 80 may not include the third insulating portion 86.

[0072] The insulating member 80 is composed of, for example, a resin having electrical insulation properties. Examples of such resins include polyolefin resins such as polypropylene (PP), fluorinated resins such as perfluoroalkoxyethylene copolymer (PFA) and polytetrafluoroethylene (PTFE), and polyphenylene sulfide (PPS).

[0073] The insulating member 80 can be composed of a plurality of members, but is preferably an integral body (integrally molded product) composed of one member. Since the insulating member 80 is an integral body, the airtightness between the first insulating portion 82 and the second insulating portion 84 is improved. In this embodiment, the insulating member 80 is also an integral body including the first insulating portion 82, the second insulating portion 84, and the third insulating portion 86 continuously, and the sealing performance in the vicinity of the first through hole 18 is improved. That is, the insulating member 80 is arranged between the first region 71 and the sealing plate 14, further passes through the first through hole 18, and contacts the peripheral region of the first through hole 18 on the outer surface 14a of the sealing plate 14.

[0074] In addition, in the present technology, it is preferable that the insulating member 80, the sealing plate 14, and the first current collecting member 70 are integrally molded products. In other words, the sealing plate 14 and the first current collecting member 70 are molded with the insulating member 80. Thereby, since the insulating member 80 is in close contact with the sealing plate 14 and the first current collecting member 70, the airtightness of the first through hole 18 provided in the sealing plate 14 and its periphery is improved. In the present embodiment, in addition to the sealing plate 14 and the first current collecting member 70, the positive electrode terminal member 30 is also molded with the insulating member 80, and the insulating member 80, the sealing plate 14, the first current collecting member 70, and the positive electrode terminal member 30 are integrally molded products.

[0075] Note that the insulating member 80 can also be used on the negative electrode side in the same manner. In this case, it can be understood by appropriately reading the positive electrode as the negative electrode in the above description.

[0076] As shown in FIGS. 11 and 12, a first surface treatment portion 92 may be provided in the vicinity of the periphery of the first through hole 18 on the inner surface 14b of the sealing plate 14 (the first wall). The first surface treatment portion 92 is in contact with the insulating member 80. By providing the first surface treatment portion 92, the airtightness and the bonding strength between the inner surface 14b of the sealing plate 14 and the insulating member 80 in the vicinity of the first through hole 18 can be improved, so that the sealing performance in the vicinity of the first through hole 18 can be improved. The first surface treatment portion 92 may be provided in at least a part of the vicinity of the periphery of the first through hole 18, but is preferably provided on the entire periphery so as to surround the first through hole 18.

[0077] The first surface treatment portion 92 is preferably processed so that the surface roughness becomes large (that is, it is a rough surface portion). The arithmetic mean roughness (Ra) of the first surface treatment portion 92 is, for example, preferably at least twice as large as the arithmetic mean roughness of the portion (the portion not subjected to roughening treatment) of the inner surface 14b of the sealing plate 14 (the first wall) excluding the first surface treatment portion 92, and may be three times or more, or four times or more. Note that the upper limit is not particularly limited, but may be, for example, 10 times or less. The greater the arithmetic mean roughness, the more the adhesiveness between the first surface treatment portion 92 and the insulating member 80 is improved by the anchor effect. The arithmetic mean roughness in the present technology refers to that measured using a stylus-type surface roughness measuring instrument based on JIS B0601:2001. As the surface treatment method of the first surface treatment portion 92, known methods can be applied, and examples thereof include methods such as chemical etching, laser processing, and blasting.

[0078] The first surface treatment portion 92 may be subjected to a treatment for forming a chemical bond with the resin. As the surface treatment method, known methods can be applied, and examples thereof include a method such as a silane coupling treatment.

[0079] As shown in FIGS. 11 and 12, in the present embodiment, the area of the lower surface 30b of the positive electrode terminal member 30 is larger than the area of the upper surface 72a of the protruding portion 72 of the first current collecting member 70. Thereby, the contact surface between the lower surface 30b of the positive electrode terminal member 30 and the insulating member 80 becomes large, and the strength of the positive electrode terminal member 30 can be improved. In this case, a second surface treatment portion 94 may be provided on the lower surface 30b of the positive electrode terminal member 30. The second surface treatment portion 94 is in contact with the insulating member 80. In the second surface treatment portion 94, the adhesiveness with the insulating member 80 is improved, and the airtightness and adhesive strength can be improved.

[0080] The second surface treatment portion 94 is preferably processed to have a large surface roughness (i.e., it is a rough surface portion). The arithmetic mean roughness (Ra) of the second surface treatment portion 94 is preferably, for example, more than twice as large as the arithmetic mean roughness of the portion of the positive electrode terminal member 30 where no surface treatment is performed (for example, the upper surface or side surface of the positive electrode terminal member 30), and may be three times or more, or four times or more. Note that the upper limit is not particularly limited, but may be, for example, 10 times or less. The larger the arithmetic mean roughness, the more the adhesion between the second surface treatment portion 94 and the insulating member 80 is improved by the anchor effect. Note that a known method can be applied as the surface treatment method of the second surface treatment portion 94, and examples thereof include methods such as chemical etching, laser processing, and blasting.

[0081] The second surface treatment portion 94 may be subjected to a treatment for forming a chemical bond with the resin. As the surface treatment method, a known method can be applied, and examples thereof include a method such as a silane coupling treatment.

[0082] The battery 100 as described above can be manufactured, for example, by a manufacturing method including a preparation step and a sealing step. Here, the preparation step includes an integral molding step. Note that the manufacturing method of the battery 100 is not limited to the manufacturing method described here.

[0083] In the preparation step, the exterior body 12, the sealing plate 14, the first current collector member 70, and the electrode body 20a are prepared. The electrode body 20a may be the electrode body group 20. Here, if necessary, the positive electrode terminal member 30, the negative electrode terminal member 40, the positive electrode second current collector 52, and the negative electrode second current collector 62 may be further prepared.

[0084] In the integral molding process, the sealing plate 14, the first current collector member 70, and the insulating member 80 are integrally molded. In the battery 100 described above, the positive electrode terminal member 30 is also integrally molded. The integral molding method can be performed according to a conventionally known method such as that described in Japanese Patent Application Laid-Open No. 2021-086813. The integral molding process can be carried out, for example, by a method including a component setting process, an upper mold setting process, an injection molding process, and a component removal process using a molding die.

[0085] In the component setting process, a molding die capable of realizing the structure of the desired insulating member 80 is prepared. The molding die includes, for example, an upper mold and a lower mold. The upper mold has a gate portion for injecting the molten resin for forming the insulating member 80. First, the first current collector member 70 and the sealing plate 14 are placed on the lower mold. It is preferable that the portion of the first current collector member 70 where the insulating member 80 is not disposed is in contact with the lower mold. For example, the lower surface 71b of the first region 71 (base portion 71c) and the lower surface of the second region 73 may be disposed in contact with the lower mold without a gap. Further, the lower mold preferably has a support portion that contacts and supports the lower surface 72b of the protruding portion 72 of the first current collector member 70. By supporting the protruding portion 72 with the support portion, pressure can be applied from the upper surface 72a side of the protruding portion 72, and the lower surface of the first current collector member 70 can be brought into close contact with the lower mold. Thereby, it is possible to prevent the molten resin of the insulating member 80 from entering the lower surface of the first current collector member 70. Note that the through hole 82a of the first insulating portion 82 of the insulating member 80 may be a mark where such a support portion was disposed. The sealing plate 14 is positioned so that at least a part of the protruding portion 72 of the first current collector member 70 is disposed inside the first through hole 18.

[0086] In the upper mold set-up process, after arranging the first current collector member 70 and the sealing plate 14, the upper mold is arranged on the outer surface 14a side of the sealing plate 14. At this time, it is preferable that the upper mold is in contact with the outer surface 14a of the sealing plate 14 at the peripheral edge of the forming portion of the third insulating portion 86 so that the molten resin does not flow into the outer surface 14a of the sealing plate 14. Further, it is preferable that the upper mold is in contact with the upper surface 72a of the protruding portion 72. Thereby, it is possible to prevent the insulating member from being arranged on the upper surface 72a of the protruding portion 72. Also, in the support portion of the lower mold and the upper mold, since both surfaces of the upper surface 72a of the protruding portion 72 can be sandwiched, pressure can be stably applied to the protruding portion 72.

[0087] In the injection molding process, the molten resin in which the resin constituting the insulating member 80 is melted is injected from the gate portion of the upper mold. The injected molten resin is injected into the upper mold, further passes through the first through hole 18, and is filled into the lower mold. The molding die is preferably pre-heated before being filled with the molten resin. The heating temperature is not limited and can be, for example, 100°C to 200°C.

[0088] In the component removal process, first, the filled molten resin is cooled. Thereby, the molten resin solidifies and the insulating member 80 is manufactured. Then, the upper mold is separated from the lower mold, and the sealing plate 14, the first current collector member 70, and the integrally molded product molded by the insulating member 80 are taken out. Then, if necessary, the gate portion and the molding burr may be removed.

[0089] In addition, when the battery 100 includes the positive electrode terminal member 30, in the component set-up process, the first current collector member 70 and the positive electrode terminal member 30 may be connected in advance and arranged in the lower mold. Thereby, the positive electrode terminal member 30, the first current collector member 70, the sealing plate 14, and the insulating member 80 can be integrally molded. Also, the description of the above integrally molding process is about the periphery of the first through hole 18, but the same process can be carried out in the second through hole 19.

[0090] In the sealing process, first, the integrally molded product prepared above and the electrode body 20a are connected. At this time, the first current collector member 70 integrally molded and the electrode tab of the electrode body 20a are directly connected. Alternatively, the first current collector member 70 and the electrode body 20a may be connected via the positive electrode second current collector portion 52 or the negative electrode second current collector portion 62. Next, the electrode body 20a is inserted through the opening 12h of the exterior body 12, and the integrally molded sealing plate 14 and the periphery of the opening 12h of the exterior body 12 are joined by laser welding or the like. Note that the electrode body holder 29 may be interposed between the exterior body 12 and the electrode body 20a. Next, an electrolytic solution is injected through the liquid injection hole 15, and the liquid injection hole 15 is sealed with a sealing member, thereby sealing the case 10. As described above, the battery 100 can be manufactured.

[0091] The battery 100 can be used for various applications. For example, it can be suitably used as a power source (driving power source) for a motor mounted on a vehicle such as a passenger car or a truck. The type of the vehicle is not particularly limited, and examples thereof include a plug-in hybrid electric vehicle (PHEV), a hybrid electric vehicle (HEV), and a battery electric vehicle (BEV). The battery 100 can also be suitably used as a single battery constituting a battery pack.

[0092] As described above, some embodiments of the present technology have been described, but the above embodiments are merely examples. The present technology can be implemented in various other forms. The technology described in the claims includes various modifications and changes of the above-exemplified embodiments. For example, it is possible to replace a part of the above-described embodiments with other embodiments, and it is also possible to add other embodiments to the above-described embodiments. Further, if the technical features are not described as essential, they can be appropriately deleted.

[0093] For example, in the above-described embodiment, the upper surface 72a of the protruding portion 72 of the first current collecting member 70 was disposed inside the first through hole 18. However, the upper surface 72a of the protruding portion 72 may be disposed outside the case 10. In this embodiment, the positive electrode terminal member 30 may not be provided. For example, an external member (e.g., a bus bar) can be easily directly connected to the upper surface 72a of the protruding portion 72 disposed outside the case 10 without passing through the positive electrode terminal member. Thereby, since the number of members forming the conduction path can be reduced, cost reduction can be achieved.

[0094] FIG. 13 is a corresponding view of FIG. 12 of the battery 200 according to another embodiment. Here, a recess 30c is provided on the lower surface 30b of the positive electrode terminal member 30. A convex portion 72c is provided on the upper surface 72a of the protruding portion 72 of the first current collecting member 70. Further, a recess 72d is provided on the lower surface 72b of the protruding portion 72. The recess 72d is located on the back side of the convex portion 72c and may be a structure generated when the plate-shaped first current collecting member 70 is deformed to provide the convex portion 72c. The convex portion 72c on the upper surface 72a of the protruding portion 72 of the first current collecting member 70 is fitted into the recess 30c on the lower surface 30b of the positive electrode terminal member 30. Thereby, positioning of the positive electrode terminal member 30 becomes easy. Further, the joining strength between the positive electrode terminal member 30 and the first current collecting member 70 can be improved. Note that the configuration other than the above may be the same as the configuration of the battery 100.

[0095] As described above, specific aspects of the technology disclosed herein include those described in the following items. Item 1: An electrode body including a first electrode and a second electrode, A case for housing the electrode body, A first current collecting member electrically connected to the first electrode, A power storage device comprising: The case has a first wall, The first wall has a first through hole, The first current collecting member has a first region disposed along the inner surface of the first wall, A protruding portion protruding toward the first wall is provided in the first region. At least a part of the protruding portion is disposed within the first through hole. The first current collecting member has a second region on a lateral side of the first region. A first slit is formed between the first region and the second region. The second region is disposed along an inner surface of the first wall. The second region is a power storage device that faces the inner surface of the first wall via an insulating member. Item 2: The power storage device according to Item 1, wherein the insulating member is disposed within the first slit. Item 3: The first current collecting member has a third region on a side opposite to the second region with respect to the first region. A second slit is formed between the first region and the third region. The third region is disposed along the inner surface of the first wall. The third region faces the first wall via the insulating member. The power storage device according to Item 1 or 2. Item 4: The power storage device according to Item 3, wherein the insulating member is disposed within the second slit. Item 5: The insulating member is disposed between the first region and the first wall, further passes through the first through hole, and contacts a peripheral region of the first through hole on an outer surface of the first wall. The power storage device according to any one of Items 1 to 4. Item 6: The power storage device according to any one of Items 1 to 5, wherein the first wall is substantially rectangular in a plan view, and in a longitudinal direction of the first wall, a length of the first region is greater than a longest length of the first through hole provided in the first wall. Item 7: The power storage device according to any one of Items 1 to 6, wherein the insulating member is disposed on a side of the protruding portion closer to the electrode body. Item 8: The power storage device according to any one of Items 1 to 7, wherein a surface treatment portion is provided near a periphery of the first through hole on an inner surface of the first wall, and the surface treatment portion is in contact with the insulating member. Item 9: The power storage device according to Item 8, wherein the arithmetic mean roughness of the surface treatment portion is at least twice as large as the arithmetic mean roughness of the portion of the inner surface of the first wall excluding the surface treatment portion.

Explanation of Signs

[0096] 10 Case 12 Exterior body 14 First wall (sealing plate) 15 Liquid injection hole 16 Sealing member 17 Gas discharge valve 18 First through hole 19 Second through hole 20 Electrode body group 20a, 20b, 20c Electrode bodies 22 First electrode (positive electrode) 24 Second electrode (negative electrode) 26 Separator 30 Positive electrode terminal member 40 Negative electrode terminal member 50 Positive electrode current collector 51 First positive electrode current collector 52 Second positive electrode current collector 60 Negative electrode current collector 61 First negative electrode current collector 62 Second negative electrode current collector 70 First current collector member 71 First region 72 Protrusion 73 Second region 74 First slit 75 Third region 76 Second slit 77 Fourth region 78 Fifth region 80 Insulating member 82 First insulating portion 84 Second insulating portion 86 Third insulating portion 92 First surface treatment portion 94 Second surface treatment portion 100 Power storage device (battery)

Claims

1. An electrode body including a first electrode and a second electrode; A case for housing the electrode body; A first current collecting member electrically connected to the first electrode; A power storage device comprising: The case has a first wall; The first wall has a first through hole; The first current collecting member has a first region disposed along the inner surface of the first wall; A protruding portion protruding toward the first wall is provided in the first region; At least a part of the protruding portion is disposed in the first through hole; The first current collecting member has a second region on a lateral side of the first region; A first slit is formed between the first region and the second region; The second region is disposed along the inner surface of the first wall; The second region faces the inner surface of the first wall via an insulating member; The insulating member is disposed in the first slit; A power storage device.

2. An electrode body including a first electrode and a second electrode; A case for housing the electrode body; A first current collecting member electrically connected to the first electrode; A power storage device comprising: The case has a first wall; The first wall has a first through hole; The first current collecting member has a first region disposed along the inner surface of the first wall; A protruding portion protruding toward the first wall is provided in the first region; At least a part of the protruding portion is disposed in the first through hole; The first current collecting member has a second region on a lateral side of the first region; A first slit is formed between the first region and the second region; The second region is disposed along the inner surface of the first wall; The second region faces the inner surface of the first wall via an insulating member; The first current collecting member has a third region on a side opposite to the second region with respect to the first region; A second slit is formed between the first region and the third region; The third region is disposed along the inner surface of the first wall; The third region faces the first wall via the insulating member; The insulating member is disposed in the second slit; A power storage device.

3. The power storage device according to claim 2, wherein the insulating member is disposed in the first slit.

4. An electrode body including a first electrode and a second electrode; A case for housing the electrode body; A first current collecting member electrically connected to the first electrode; A power storage device comprising: The case has a first wall; The first wall has a first through hole; The first current collecting member has a first region disposed along the inner surface of the first wall, a protruding portion protruding toward the first wall is provided in the first region, at least a part of the protruding portion is disposed in the first through hole, the first current collecting member has a second region beside the first region, a first slit is formed between the first region and the second region, the second region is disposed along the inner surface of the first wall, the second region faces the inner surface of the first wall via an insulating member, the insulating member is disposed on the side of the protruding portion toward the electrode body. Power storage device.

5. The insulating member is disposed between the first region and the first wall, further passes through the first through hole, and contacts a peripheral region of the first through hole on the outer surface of the first wall. The power storage device according to any one of claims 1 to 4.

6. The first wall is substantially rectangular in plan view, In the longitudinal direction of the first wall, the length of the first region is larger than the longest length of the first through hole provided in the first wall. The power storage device according to any one of claims 1 to 4.

7. The insulating member is disposed on the side of the protruding portion toward the electrode body. The power storage device according to any one of claims 1 to 3.

8. On the inner surface of the first wall, a surface treatment portion is provided near the periphery of the first through hole, and the surface treatment portion is in contact with the insulating member. The power storage device according to any one of claims 1 to 4.

9. The arithmetic mean roughness of the surface treatment portion is more than twice as large as the arithmetic mean roughness of the portion of the inner surface of the first wall excluding the surface treatment portion. The power storage device according to claim 8.

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