Energy Storage Module

Abstract

This electrical storage module is provided with: an insulating substrate which opposes an electrical storage group comprising a plurality of electrical storage devices and has a plurality of through-holes; a plurality of current collecting foils which are disposed at intervals from each other on a first surface of the insulating substrate on the side opposite to a surface opposing the electrical storage group; and an insulating sheet disposed so as to cover the plurality of current collecting foils. The plurality of current collecting foils include a first current collecting foil and a second current collecting foil which are adjacent to each other with an interval therebetween in a direction parallel to the first surface. The first current collecting foil includes a tongue-like first lead portion extending from an edge, passed through a hole in the insulating substrate, and electrically connected to the positive pole of a battery. The second current collecting foil includes a tongue-like second lead portion extending from an edge, passed through a hole in the insulating substrate, and electrically connected to the negative pole of the battery.

Description

[Technical field]

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

[0002] Conventionally, there is an energy storage module described in Patent Document 1. This energy storage module includes a plurality of cylindrical batteries, a positive electrode current collector, and a negative electrode current collector. The positive electrode current collector is used to connect the positive electrodes of the plurality of cylindrical batteries in parallel on one side in the axial direction of the cylindrical batteries, and the negative electrode current collector is used to connect the negative electrodes of the plurality of cylindrical batteries in parallel on the other side in the axial direction of the cylindrical batteries. This energy storage module uses the positive electrode current collector and the negative electrode current collector to appropriately connect the plurality of cylindrical batteries in parallel, thereby increasing the battery capacity. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] International Publication No. 2018 / 003468 Summary of the Invention [Problem to be solved by the invention]

[0004] If the positive and negative current collector plates are both arranged on one side (the same side) in the height direction of the electricity storage device, the electricity storage module can be configured compactly. However, when such a configuration is adopted, it becomes necessary to arrange the positive and negative current collector plates that constitute the current collector foil at a distance from each other, making it impossible to form the current collector plates as a single unit, and the handling of the current collector plates becomes difficult. An object of the present disclosure is to provide an electricity storage module that can be configured compactly and that also improves the handling of the current collector plates. [Means for solving the problem]

[0005] The electricity storage module according to the present disclosure includes an electricity storage group including a plurality of electricity storage devices each having a first electrode and a second electrode, and a plate-shaped current collecting member that electrically connects the plurality of electricity storage devices to each other and faces the electricity storage group, the current collecting member having an insulating substrate facing the electricity storage group and having a plurality of holes, a plurality of current collecting foils arranged side by side on a first surface of the insulating substrate that is on the opposite side to the surface facing the electricity storage group, and an insulating sheet provided on the plurality of current collecting foils, The current collecting foil and the second current collecting foil are arranged at a distance from each other, the insulating substrate has one or more holes whose at least a portion overlaps between the first current collecting foil and the second current collecting foil when viewed from the height direction, the first current collecting foil has a tongue-shaped first lead portion extending from an edge and passing through a hole in the insulating substrate to be electrically connected to a first electrode of the energy storage device, the second current collecting foil has a tongue-shaped second lead portion extending from an edge and passing through a hole in the insulating substrate to be electrically connected to a second electrode of the energy storage device, and the insulating sheet extends to cover the first current collecting foil and the second current collecting foil. Effect of the Invention

[0006] According to the electricity storage module of the present disclosure, the multiple current collecting foils are arranged side by side on the first surface of the insulating substrate opposite the surface facing the electricity storage group, so that the multiple current collecting foils can be arranged on only one side in the height direction, and the electricity storage module can be configured compactly. Furthermore, because the insulating sheet extends so as to cover the first current collecting foil and the second current collecting foil, both the first and second current collecting foils can be fixed to the insulating sheet, and the first and second current collecting foils can be handled as a single unit. This also improves the ease of handling of the current collecting foils when producing the current collecting member. [Brief description of the drawings]

[0007] [Figure 1] FIG. 2 is a partial perspective view of an energy storage module according to an embodiment of the present disclosure. [Diagram 2] 4 is a plan view of a current collecting member of the electricity storage module. FIG. [Diagram 3] FIG. [Figure 4] 3 is a plan view showing a part of the current collecting member shown in FIG. 2. [Diagram 5] 3 is a plan view showing a part of the insulating sheet portion in the region indicated by R1 in FIG. 2, as viewed from the side opposite to the battery side. [Figure 6] 3 is a plan view showing a part of the current collecting foil in the region indicated by R1 in FIG. 2, as viewed from the side opposite to the battery side. [Figure 7] 3 is a plan view showing a part of the insulating substrate in the region indicated by R1 in FIG. 2, as viewed from the side opposite the battery side. FIG. [Figure 8] FIG. 2 is a plan view showing a structure of a current collecting foil of the current collecting member. [Figure 9] 4 is a plan view showing a portion of adjacent current collecting foils of the electricity storage module. FIG. [Figure 10] 10 is a plan view of an electricity storage module according to a modified example, corresponding to FIG. 9. FIG. [Figure 11] 13 is a plan view of a current collecting foil in a current collecting member used in a power storage module according to a further modified example. FIG. [Figure 12] 10 is a plan view corresponding to FIG. 9 of an electricity storage module according to a further modified example. FIG. [Figure 13] FIG. 4 is a plan view showing an example of a layout of battery arrangement in an electricity storage group. [Figure 14] 13 is a plan view showing another example of the layout of the arrangement of batteries in the electricity storage group. FIG. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0008] Hereinafter, the embodiments according to the present disclosure will be described in detail with reference to the accompanying drawings. In addition, when multiple embodiments and modified examples are included below, it is assumed from the beginning that new embodiments will be constructed by appropriately combining the characteristic parts of those. In addition, in the following examples, the same components are given the same symbols in the drawings, and duplicated explanations are omitted. In addition, multiple drawings include schematic diagrams, and the dimensional ratios of the length, width, height, etc. of each member between different drawings do not necessarily match. In addition, in the following explanations and drawings, the X direction, which is the first direction, indicates the arrangement direction in which two or more cylindrical batteries 11 belonging to each row are arranged with respect to the cylindrical batteries 11 arranged in multiple rows. In addition, the Y direction indicates the orthogonal direction perpendicular to the arrangement direction, and the Z direction indicates the height direction of the storage module 1. The X direction, the Y direction, and the Z direction are perpendicular to each other. In addition, the storage device may be a rectangular secondary battery or a capacitor, but in this embodiment, the storage device is a cylindrical secondary battery. Furthermore, when the word "approximately" is used in this specification, it is used in the same sense as the word "roughly speaking," and the requirement of "approximately..." is met if a person looks roughly like... For example, the requirement of approximately circular is met if a person looks roughly circular. Furthermore, among the components described below, those components that are not described in the independent claim showing the highest concept are optional components and are not required components.

[0009] FIG. 1 is a partial perspective view of a power storage module 1 according to an embodiment of the present disclosure. As shown in FIG. 1, the power storage module 1 includes a power storage group 10, a first holder 20, a second holder (not shown), and a current collecting member 30. The power storage group 10 includes a plurality of cylindrical secondary batteries (hereinafter simply referred to as batteries) 11 as an example of a plurality of power storage devices. The batteries 11 include, for example, an electrode group in which a positive electrode and a negative electrode are wound with a separator interposed therebetween, a cylindrical outer can in which the electrode group is accommodated together with an electrolyte, and a sealing body that seals the opening of the outer can in a state insulated from the outer can. The outer can is electrically connected to the negative electrode of the electrode group, and the sealing body is electrically connected to the positive electrode. An insulating gasket is disposed between the outer peripheral surface of the sealing body and the inner peripheral surface of the opening end of the outer can. The opening end of the outer can is bent toward the inside of the outer can together with the gasket, and covers the outer peripheral edge of the sealing body.

[0010] The first holder 20 is disposed so as to cover the bottom of the exterior can of the battery 11. The first holder 20 has first housing sections that open to the battery 11 side and have the same number of first housing sections as the number of the batteries 11, and each first housing section has a concave shape corresponding to the end opposite to the positive electrode side of the battery 11. On the other hand, the second holder is disposed on the sealing plate side of the battery 11. The second holder accommodates the sealing body of the battery 11 and the opening of the exterior can, and has second housing sections that have the same number of second housing sections as the number of the batteries 11. Each of the second housing sections has an inner peripheral surface facing the outer peripheral surface of the exterior can, and a height direction positioning portion that extends from the inner peripheral surface toward the inside of the second housing section and contacts a part of the peripheral portion of the end face of the battery 11 on the sealing body side. For example, the bottom side of the exterior can of each battery 11 is accommodated in the first housing section, and the sealing body side of each battery 11 is accommodated in the second housing section, whereby the multiple batteries 11 in the storage battery group 10 are positioned. The number of first and second storage sections may be greater than the number of power storage devices.

[0011] FIG. 2 is a plan view of the current collecting member 30, and FIG. 3 is a bottom view of the current collecting member 30 as viewed from the electricity storage group side. In FIG. 2 and FIG. 3, dotted lines indicate edges of the insulating sheet 70, dotted hatching areas are areas where the current collecting foils 50 are present, and diagonal hatching areas are areas where the insulating substrate 40 is present. The current collecting member 30 has a plate shape and includes an insulating substrate 40, a plurality of metal current collecting foils 50, and an insulating sheet 70. The insulating substrate 40, the current collecting foils 50, and the insulating sheet 70 are arranged to be stacked, and the current collecting member 30 has a three-layer structure. The insulating substrate is made of an insulating material and has a plate shape. The rigidity of the insulating substrate is higher than the rigidity of the insulating sheet 70. The insulating substrate 40 faces the electricity storage group 10, and the three layers are arranged in the order of the insulating substrate, the plurality of current collecting foils, and the insulating sheet 70 from the side closer to the electricity storage group 10.

[0012] The insulating substrate 40 is composed of, for example, a glass composite substrate, a glass epoxy substrate, a Teflon (registered trademark) substrate, an alumina (ceramics) substrate, a PC (polycarbonate) substrate, an acrylic substrate, a composite substrate, etc. It is preferable that the insulating substrate 40 has heat resistance equivalent to that of a glass epoxy substrate or greater than that of a glass epoxy substrate.

[0013] The multiple current collecting foils 50 are made of metal foil, such as aluminum foil or copper foil. The multiple current collecting foils 50 are arranged side by side on a first surface of the insulating substrate 40, which is opposite to the surface facing the power storage group 10. The insulating sheet 70 may be made of any sheet having insulating properties, such as a PET (polyethylene terephthalate) film, a PC (polycarbonate) film, a polyimide film, or a fluorine film. The insulating sheet 70 is more flexible than the insulating substrate 40. This configuration allows the multiple current collecting foils 50 to be unwound or wound when obtaining them on the insulating sheet 70, thereby increasing productivity in producing the current collecting member. The insulating sheet 70 has an integral structure and is arranged on the side of the multiple current collecting foils opposite the insulating substrate side, and is arranged so as to cover the side of the multiple current collecting foils 50 opposite the power storage group 10. All of the multiple current collecting foils 50 are attached to the insulating sheet 70 with an adhesive or the like. The structure in which a plurality of current collecting foils 50 and insulating sheet 70 are integrated can be formed, for example, by adhering a sheet-like conductive foil integral with insulating sheet 70 and then etching this conductive foil into a predetermined shape.

[0014] The integrated structure of the multiple current collecting foils 50 and insulating sheet 70 is attached and fixed to the side of the insulating substrate 40 opposite the side of the power storage unit 10, for example, with an adhesive or double-sided tape, so that the insulating substrate 70, the multiple current collecting foils 50, and the insulating sheet 70 are integrated to form the current collecting member 30. Furthermore, the insulating substrate 40 is adhered to a second holder (not shown) and fastened with screws. In this way, the current collecting member 30, the power storage unit 10, and the first and second holders are integrated to form the main part of the power storage module. The main part of the power storage module may be housed in a case (not shown) while being positioned relative to the case.

[0015] Fig. 4 is a plan view showing a part of the current collecting member in Fig. 2. Fig. 5 is a plan view showing a part of the insulating sheet 70 in the region indicated by R1 in Fig. 2, as viewed from the opposite side to the battery 11 side, and Fig. 6 is a plan view showing a part of the current collecting foil 50 in the region indicated by R1 in Fig. 2, as viewed from the opposite side to the battery 11 side. Fig. 7 is a plan view showing a part of the insulating substrate 40 in the region indicated by R1 in Fig. 2, as viewed from the opposite side to the battery 11 side. Fig. 8 is a plan view showing the structure of the current collecting foil 50 in the current collecting member 30.

[0016] 8, the multiple current collecting foils 50 included in the energy storage module 1 are positioned at intervals in an orthogonal direction (Y direction) perpendicular to the arrangement direction (X direction) in which the batteries 11 are arranged in multiple rows. The multiple current collecting foils 50 are arranged at a distance in the Y direction (included in the direction parallel to the first surface) and include a first current collecting foil 51 and a second current collecting foil 52 adjacent to each other in the Y direction.

[0017] Gap 55 provided between first current collector foil 51 and second current collector foil 52 includes a plurality of elongated linear first regions 55a arranged at intervals, and a plurality of second regions 55b that communicate with both of the two adjacent first regions 55a and overlap at least a portion of the axial end face (e.g., the top surface of the sealing body) of battery 11 in the height direction (Z direction). As will be described later, insulating substrate 40 has one or more through holes at least a portion of which overlaps between first current collector foil 51 and second current collector foil 52 when viewed from the Z direction, and more specifically, at least a portion of each through hole of insulating substrate 40 overlaps with second region 55b when viewed from the Z direction.

[0018] The first current collecting foil 51 has a tongue-shaped first lead portion 57 that extends from an edge and passes through a through hole in the insulating substrate 40 to electrically connect to a positive electrode as a first electrode of the battery 11. The second current collecting foil 52 has a tongue-shaped second lead portion 58 that extends from an edge and passes through a through hole in the insulating substrate 40 to electrically connect to a negative electrode as a second electrode of the battery 11. A part of the edge of the second region 55b is defined by the edge of the first lead portion 57 and the edge of the second lead portion 58. As shown in Figs. 5 and 6, the insulating sheet 70 has a through hole 71 that at least partially overlaps with the second region 55b when viewed from the Z direction, and as shown in Figs. 6 and 7, the insulating substrate 40 has a through hole 41 that at least partially overlaps with the second region 55b when viewed from the Z direction.

[0019] 2 to 4, insulating sheet 70 has a tongue-shaped lead protection portion 89 that overlaps all of first lead portion 57 and all of second lead portion 58 when viewed from the Z direction. Through hole 39 of current collecting member 30 is present, which is generated by all of through hole 71, second region 55b, and through hole 41 overlapping in the Z direction, and parts 39a and 39b of through hole 39 are present on both sides of lead protection portion 89 in the X direction, respectively. In other words, first lead portion 57, second lead portion 58, and lead protection portion 89 protrude to the inside of through hole 39 of current collecting member 30. Insulating sheet 70 covers the entire surface of current collecting foil 50 on the side opposite to the power storage group 10 side. This ensures that current collecting foil 50 is insulated from the outside.

[0020] Furthermore, when viewed from the height direction with the electricity storage group 10, first holder 20, second holder (not shown), and current collecting member 30 integrated together, the positive electrode of battery 11 overlaps the tip of first lead portion 57, and a portion of the peripheral portion of the outer casing constituting the negative electrode of battery 11 overlaps the tip of second lead portion 58.

[0021] In this context, as shown in FIG. 3, the through hole 41 of the insulating substrate 40 is larger than both the through hole 71 and the second region 55b in the region other than the base of the first and second lead portions 57, 58. Therefore, the first and second lead portions 57, 58 can be easily pushed down toward the battery 11, and the end surface portion of the battery 11 exposed to the current collector foil 50 side through the through hole 41 can be widened. As a result, the first lead portion 57 can be reliably and easily welded to the positive electrode of the battery 11, and the second lead portion 58 can be reliably and easily welded to the negative electrode of the battery 11. As described above, the flexibility of the insulating sheet 70 is higher than that of the insulating substrate 40. Therefore, when the first and second lead portions 57, 58 are pushed down, the insulating sheet 70 can be easily pushed down so as to follow the first and second lead portions 57, 58.

[0022] As shown in Fig. 2, the circuit portion of the energy storage module 1 has a circuit structure in which three structures in which five batteries 11 (see Fig. 1) are connected in parallel are connected in series. The energy storage module 1 increases its capacity by connecting multiple batteries 11 in parallel in this way. Furthermore, by connecting multiple structures in which multiple batteries 11 are connected in parallel in series, the electromotive force, i.e., the voltage of the power supplied, is increased.

[0023] Although not described in detail, the power storage module 1 has a high-potential side current collecting plate 90 (see FIG. 1) that is electrically connected to the current collecting foil 50 with the lowest potential and that is adhered to the insulating substrate 40, and a low-potential side current collecting plate (not shown) that is electrically connected to the current collecting foil 50 with the highest potential and that is adhered to the insulating substrate 40. The power generated in the power storage module 1 is adapted to be extracted to the outside using the low-potential side current collecting plate 90 and the high-potential side current collecting plate.

[0024] As described above, according to the electricity storage module 1 of the present disclosure, the multiple current collecting foils 50 are arranged side by side on the first surface of the insulating substrate 40, which is opposite to the surface facing the electricity storage group 10. Therefore, the multiple current collecting foils 50 can be arranged only on one side in the Z direction, and the electricity storage module 1 can be made compact and excellent in productivity. In addition, since the integrated insulating sheet 70 extends so as to cover all the discretely arranged current collecting foils 50, all the current collecting foils 50 can be fixed to the integrated insulating sheet 70, and all the current collecting foils 50 can be handled as a whole. In addition, since an insulating sheet holding multiple current collecting foils can be obtained by processing a laminate of one insulating sheet 70 and one conductive foil, productivity is improved compared to a manufacturing method in which multiple current collecting foils are obtained from individual conductive foils and these multiple current collecting foils are attached to an insulating substrate. Therefore, the handleability of the current collecting foil 50 can be improved, and the productivity of the current collecting member and therefore the electricity storage module is improved. Furthermore, because the side of current collecting foil 50 opposite to the power storage group 10 side is covered with insulating sheet 70, current collecting foil 50 can be reliably insulated from the outside and mechanical strength can also be ensured. When obtaining multiple current collecting foils by etching the conductive foil on the insulating sheet, processing such as making holes in the insulating sheet may be performed after obtaining the multiple current collecting foils.

[0025] 2 again, the second lead portions 58 include one or more straight lead portions 81 extending linearly and one or more bent lead portions 82 bent into a substantially U-shape in plan view when viewed from the height direction. Further, the second region 55b has a part of its edge defined by an edge of the bent lead portion 82. The base side of the bent lead portion 82 extends in the X direction.

[0026] Moreover, the first lead portion 57 which is electrically connected to and closest to the bent lead portion 82 is an inclined lead portion 88 including an inclined portion 88a which inclines to one side in the X direction so as to move away from the bent lead portion 82 toward the root side of the bent lead portion 82 in the Y direction. Moreover, as shown in Fig. 8, the first current collecting foil 51 having the inclined lead portion 88 has a pair of bottomed slits 95, 96 on both sides in the X direction on the root side of the inclined lead portion 88. Next, this configuration will be described.

[0027] FIG. 9 is a plan view showing a part of adjacent current collecting foils 50 of the energy storage module 1. The lead portion serves as a fuse that is cut when an overcurrent flows, and therefore needs to have a certain length to ensure that the cut occurs when an overcurrent flows. Here, as shown in FIG. 9, the second lead portion 58 is a bent lead portion 82 that is bent into a substantially U-shape in a plan view when viewed from the height direction. This bent lead portion 82 can shorten the current collection path from the base of the bent lead portion 82 to the base of the first lead portion 57 connected in series to the bent lead portion 82, as shown by the arrow A in FIG. 9, in comparison with the case where the second lead portion extends in a straight line. Therefore, the current collection resistance between the base of the bent lead portion 82 and the first lead portion 57 connected in series to the bent lead portion 82 can be reduced, and the energy efficiency of the energy storage module 1 can be increased.

[0028] In addition, the energy storage module 1 may be used for purposes such as supplying power to electric bicycles or electric vehicles, and may be used in an environment prone to vibration. In such cases, the base of the first lead portion 57 may be easily damaged by vibration.

[0029] In this background, in order to suppress damage to the first lead portion 57, slits 95, 96 are formed on the base side of the first lead portion 57. The first lead portion 57 is disposed between the slits 95, 96. These slits 95, 96 extend the distance of the first lead portion 57. Therefore, the first lead portion 57 can easily follow the height direction due to vibration, which relieves the stress acting on the base of the first lead portion 57 and makes the first lead portion 57 less likely to be damaged by vibration.

[0030] Fig. 10 is a plan view showing a part of a current collecting foil in which slits 95, 96 adjacent to first lead portion 57 extend in the Y direction in current collecting member 30. When a pair of bottomed slits 395, 396 extending in the Y direction are formed at the base side of first lead portion 357 extending linearly along the Y direction and on both sides in the X direction as shown in Fig. 10, the width of local portion 377 between adjacent second regions 355b in current collecting foil 350 becomes smaller, making current collecting foil 350 more likely to break at local portion 377, and creating a risk of breaking the parallel connection indicated by arrow B in Fig. 10.

[0031] In contrast, in the electricity storage module 1 of the present disclosure, the first lead portion 57, which is electrically connected to and closest to the bent lead portion 82, is an inclined lead portion 88 including an inclined portion 88a that inclines to one side in the X direction as it approaches the root side of the bent lead portion 82 in the Y direction. Therefore, even if the second region 55b expands to one side in the X direction by forming the bent lead portion 82, the root of the inclined lead portion 88 can be arranged away from the second region 55b, and cutting of the current collecting foil 50 can be suppressed or prevented. Therefore, the electricity storage module 1 showing a part of the current collecting foil 50 in FIG. 9 can suppress the generation of Joule heat compared to the electricity storage module of the modified example showing a part of the current collecting foil 350 in FIG. 10, and can provide a remarkable operational effect of not only increasing the energy efficiency of the electricity storage module 1 and suppressing or preventing damage to the first lead portion 57 and the current collecting foil 50.

[0032] The present disclosure is not limited to the above-described embodiment and its modified examples, and various improvements and modifications are possible within the scope of the claims of the present application and their equivalents.

[0033] For example, as shown in Fig. 9, the case has been described where the first lead portion 57 is an inclined lead portion 88 having an inclined portion 88a. However, the first lead portion 57 is not limited to this configuration. As shown in Fig. 11, i.e., a plan view of a modified power storage module 101 corresponding to Fig. 8, and Fig. 12, i.e., a plan view of the power storage module 101 corresponding to Fig. 9, all portions of the inclined lead portion 188 may be inclined to one side in the X direction as they approach the root side of the bent lead portion in the Y direction.

[0034] The arrangement of the batteries 11 in the electricity storage group 10 may also be such that two or more batteries 11 are spaced apart not only in the line-up direction (X direction) but also in the orthogonal direction (Y direction) as shown in the plan view of Fig. 13. Alternatively, the layout may be such that two or more batteries 11 are spaced apart in a direction inclined at an acute angle to the orthogonal direction (Y direction) perpendicular to the line-up direction (X direction) as shown in the plan view of Fig. 14.

[0035] Furthermore, in the layout of the plurality of batteries 11 in the storage battery group 10 in a plan view, the direction connecting the centers of the batteries facing each other in the substantially Y direction in every other row is defined as the current collection direction. In this case, in the layout shown in FIG. 13, the current collection direction indicated by the α direction coincides with the Y direction, while in the layout shown in FIG. 14, the current collection direction indicated by the α direction is inclined at an acute angle with respect to the Y direction. When the current collection direction is defined in this way, the inclined lead portion may include an inclined portion inclined in the arrangement direction (X direction) with respect to the current collection direction (α direction) so as to move away from the root of the bent lead portion near the inclined lead portion. By inclining the inclined lead portion in this way, it is possible to prevent the width of the current collection path between the nearby bent lead portion and the inclined lead portion from narrowing.

[0036] Also, a case has been described in which slits 95, 96 are provided on both sides of the base of the first lead portion that is electrically connected to the bent lead portion 82 and is closest to the current collecting foil 50. However, as will be described below, this configuration does not necessarily have to be adopted.

[0037] In this embodiment, as shown in Fig. 5, the insulating sheet 70 has a through hole 71 including a pair of bottomed slits 78, 79 that overlap with a pair of bottomed slits 95, 96 of the current collecting foil 50 when viewed from the Z direction, so that when the first and second lead portions 57, 58 are pressed down when being welded to the electrodes of the battery 11, the insulating sheet 70 is easily pressed down following the pressing. However, in the case of this modification, the insulating sheet does not need to have such slits. Also, according to this modification, all of the first lead portions may extend linearly without having an inclined portion. [Explanation of symbols]

[0038] 1,101 Energy storage module; 10 Energy storage group; 11 Battery; 20 First holder; 30 Current collecting member; 39, 41, 71 Through hole; 40 Insulating substrate; 50, 250 Current collecting foil; 51 First current collecting foil; 52 Second current collecting foil; 55 Gap provided between first current collecting foil and second current collecting foil; 55a First region; 55b Second region; 57, 257 First lead portion; 58 Second lead portion; 68 Portion of bent lead portion electrically connected to negative electrode; 70 Insulating sheet; 78, 79 Slit; 81 Straight lead portion; 82, 282 Bent lead portion; 88, 188 Slanted lead portion; 88a Slanted portion; 89 Lead protection portion; 90 High potential side current collecting plate; 95, 96 Slit.

Claims

1. a power storage group including a plurality of power storage devices each having a first electrode and a second electrode; a plate-shaped current collecting member electrically connecting each of the plurality of power storage devices and facing the power storage group; The current collecting member is an insulating substrate facing the capacitor group and having a plurality of holes; a plurality of current collecting foils arranged side by side on a first surface of the insulating substrate that is opposite to a surface facing the electricity storage group; an insulating sheet provided on the plurality of current collecting foils; Among the plurality of current collecting foils, a first current collecting foil and a second current collecting foil adjacent to each other in a direction parallel to the first surface are disposed at a distance from each other, the insulating substrate has one or more holes at least a portion of which overlaps between the first current collecting foil and the second current collecting foil when viewed from a height direction, the first current collecting foil has a tongue-shaped first lead portion extending from an edge thereof and passing through the hole of the insulating substrate to be electrically connected to the first electrode of the power storage device; the second current collecting foil has a tongue-shaped second lead portion extending from an edge thereof and passing through the hole of the insulating substrate to be electrically connected to the second electrode of the power storage device; the insulating sheet extends to cover the first current collecting foil and the second current collecting foil, the insulating sheet is bonded to the first current collecting foil and the second current collecting foil, The insulating sheet is more flexible than the insulating substrate. Energy storage module.

2. the plurality of power storage devices are arranged along the first surface, and the first electrode and the second electrode are provided on the power collecting member side in a direction in which the power storage group and the power collecting member face each other, The energy storage module according to claim 1 .

3. The insulating sheet has a hole at least a part of which overlaps with a hole of the insulating substrate. The energy storage module according to claim 1 or 2.

4. The plurality of power storage devices are arranged in multiple rows, the first current collecting foil and the second current collecting foil are arranged at intervals from each other in an orthogonal direction perpendicular to an arrangement direction in which the two or more power storage devices are arranged in each row, a gap provided between the first current collecting foil and the second current collecting foil includes a plurality of elongated linear first regions arranged at intervals, and a plurality of second regions arranged between two adjacent first regions, communicating with both of the two first regions, and overlapping at least a portion of an end surface in an axial direction of the electricity storage device in the height direction, a part of an edge of the second region is defined by an edge of the first lead portion and an edge of the second lead portion; The second lead portions include one or more bent lead portions that are bent into a substantially U-shape in a plan view when viewed from the height direction, A base side of the bent lead portion extends in a first direction, the first lead portion which is electrically connected to the bent lead portion and is closest to the bent lead portion is an inclined lead portion including an inclined portion which inclines in the first direction away from the second lead portion toward the base side; The energy storage module according to claim 1 .

5. The first current collecting foil having the inclined lead portion has a pair of bottomed slits on both sides of the base side of the inclined lead portion in the arrangement direction. The power storage module according to claim 4 .

6. the entire inclined lead portion inclines in the first direction toward the base side; The power storage module according to claim 4 .

7. The inclined lead portion has the inclined portion in a part thereof. The power storage module according to claim 4 .

8. the insulating sheet has a hole including a pair of bottomed slits that overlap the pair of bottomed slits when viewed from the height direction; The power storage module according to claim 5 .

9. the insulating sheet has a lead protection portion that defines a part of an edge of a hole formed therein and overlaps the entire first lead portion and the entire second lead portion when viewed from the height direction; The energy storage module according to claim 1 .

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