Battery pack

Abstract

A battery pack according to one embodiment of the present technology is provided with a battery unit. Said battery unit is provided with: a plurality of batteries; and one or a plurality of heat-absorbing members each having a heat-absorbing agent and a housing body that houses the heat-absorbing agent. The heat absorbing member(s) extend in the axial direction of the battery and are disposed so as to be adjacent to at least two of the batteries. The battery unit further comprises: a battery holder that holds the plurality of batteries; a first tab that is connected to a terminal on one end side of the plurality of batteries; and a second tab that is connected to a terminal on another end side of the plurality of batteries. The first tab is formed so as to cover one end of the heat absorbing member(s) when the battery unit is viewed from the axial direction of the battery. The second tab is formed so as to cover another end of the heat absorbing member(s) when the battery unit is viewed from the axial direction of the battery.

Description

Battery pack

[0001] The present technology relates to battery packs.

[0002] As electronic devices have become widespread, development of batteries as power sources for these devices has progressed. In this case, battery packs containing multiple batteries have been proposed to facilitate easy and safe handling of the batteries.

[0003] Various studies have been conducted on technologies related to the configuration of a battery pack. Specifically, a heat-absorbing member is in contact with the side surface of a battery unit, and the heat-absorbing member contains a heat-absorbing agent (gel-like fluid) inside an exterior film (see, for example, Patent Document 1).

[0004] International Publication No. WO2010 / 098067

[0005] The heat-absorbing member exerts its heat-absorbing effect when the exterior film is torn and the heat-absorbing agent leaks out. However, if the battery pack is designed so that the heat-absorbing agent leaking from the heat-absorbing member is not retained within the battery unit but is instead discharged to the outside, the heat-absorbing effect of the heat-absorbing agent is reduced. A battery pack with a structure that provides a high heat-absorbing effect due to the heat-absorbing agent is desired. It is desirable to provide a battery pack with a structure that provides a high heat-absorbing effect due to the heat-absorbing agent.

[0006] A battery pack according to a first aspect of the present technology includes a battery unit. The battery unit includes a plurality of batteries and one or more heat-absorbing members each having a heat-absorbing agent and a housing for accommodating the heat-absorbing agent. The one or more heat-absorbing members extend in the axial direction of the batteries and are arranged adjacent to at least two of the batteries. The battery unit further includes a battery holder for holding the plurality of batteries, a first tab connected to terminals on one ends of the plurality of batteries, and a second tab connected to terminals on the other ends of the plurality of batteries. The first tab is formed to cover one end of the one or more heat-absorbing members when the battery unit is viewed in the axial direction of the batteries. The second tab is formed to cover the other end of the one or more heat-absorbing members when the battery unit is viewed in the axial direction of the batteries.

[0007] According to the battery pack according to the first aspect of the present technology, the first tab is formed to cover one end of one or more heat-absorbing members when the battery unit is viewed in the axial direction of the battery, and the second tab is formed to cover the other end of the one or more heat-absorbing members when the battery unit is viewed in the axial direction of the battery. Therefore, when the housing is torn open and the heat-absorbing agent leaks out, the first tab and the second tab act as a wall to contain the heat-absorbing agent within the battery unit. This prevents a decrease in the heat-absorbing effect of the heat-absorbing agent. Therefore, a battery pack having a structure that enhances the heat-absorbing effect of the heat-absorbing agent can be provided.

[0008] FIG. 1 is a diagram illustrating an example of a perspective configuration of a battery pack according to a first embodiment of the present technology. FIG. 2 is a diagram illustrating an example of a perspective configuration of an item contained in the battery pack. FIG. 3 is a diagram illustrating an example of an exploded perspective configuration of the battery pack. FIG. 4 is a diagram illustrating an example of a cross-sectional configuration of a battery holder. FIG. 5 is a diagram illustrating an example of a cross-sectional configuration of a battery holder. FIG. 6 is a diagram illustrating an example of an arrangement of multiple batteries in a battery unit. FIG. 7(A) is a diagram illustrating an example of a cross-sectional configuration of a heat absorption member. FIG. 7(B) is a diagram illustrating an example of a cross-sectional configuration of the heat absorption member of FIG. 7(A) taken along line A-A. FIG. 8 is a diagram illustrating an example of an exploded perspective configuration of a first tab. FIG. 9 is a diagram illustrating an example of a planar configuration of two power extraction tab components and an intermediate connection tab component included in the first tab. FIG. 10 is a diagram illustrating an example of a configuration in which the planar configuration of the battery and the heat absorption member are superimposed on the planar configuration of FIG. 9. FIG. 11 is a diagram illustrating an example of a cross-sectional configuration of FIG. 9 taken along line A-A. FIG. 12 is a diagram illustrating an example of an exploded perspective configuration of a second tab. FIG. 13 is a diagram illustrating an example of the planar configuration of two intermediate connection tab components included in the second tab. FIG. 14 is a diagram illustrating an example of a configuration in which the planar configuration of the battery and heat absorption member is superimposed on the planar configuration of FIG. 13. FIG. 15 is a diagram illustrating an example of a cross-sectional configuration taken along line A-A in FIG. 13. FIG. 16 is a diagram illustrating a procedure for engaging hooks provided on the first tab and the second tab with the control board. FIG. 17 is a diagram illustrating a modified arrangement of multiple batteries in a battery unit. FIG. 18 is a diagram illustrating an example of tabs connected to terminals on one end sides of the multiple batteries in FIG. 17. FIG. 19 is a diagram illustrating a modified planar configuration of FIG. 10. FIG. 20 is a diagram illustrating a modified planar configuration of FIG. 14. FIG. 21 is a diagram illustrating a modified planar configuration of FIG. 10. FIG. 22 is a diagram illustrating a modified planar configuration of FIG. 14. FIG. 23 is a diagram illustrating a modified perspective configuration of the first tab. FIG. 24 is a diagram illustrating an example of a cross-sectional configuration taken along line A-A in FIG. 23. Fig. 25 is a diagram illustrating a modified perspective configuration of the second tab. Fig. 26 is a diagram illustrating an example cross-sectional configuration along line A-A in Fig. 25. Fig. 27 is a diagram illustrating an example perspective configuration of a battery pack according to a second embodiment of the present technology. Fig. 28 is a diagram illustrating an example perspective configuration of an item contained in the battery pack. Fig. 29 is a diagram illustrating an example exploded perspective configuration of the battery pack. Fig. 30 is a diagram illustrating an example exploded perspective configuration of the first tab.FIG. 31(A) is a diagram illustrating an example of a planar configuration of two power supply extraction tab components included in the first tab. FIG. 31(B) is a diagram illustrating an example of a configuration in which the planar configuration of the battery and the heat absorption member is superimposed on the planar configuration of FIG. 31(A). FIG. 32 is a diagram illustrating an example of a cross-sectional configuration along line A-A of FIG. 31(A). FIG. 33 is a diagram illustrating an example of a perspective configuration of the second tab. FIG. 34 is a diagram illustrating a modified example of the planar configuration of FIG. 31(B). FIG. 35 is a diagram illustrating a modified example of the planar configuration of FIG. 31(B). FIG. 36 is a diagram illustrating a modified example of a perspective configuration of the first tab of FIG. 30. FIG. 37 is a diagram illustrating an example of a cross-sectional configuration of the first tab of FIG. 36. FIG. 38 is a diagram illustrating a modified example of the perspective configuration of the first tab of FIG. 30. FIG. 39 is a diagram illustrating an example of a cross-sectional configuration of the first tab of FIG. 38. FIG. 40 is a diagram illustrating an example of a perspective configuration of a battery pack according to a third embodiment of the present technology. FIG. 41 is a diagram showing an example of a perspective configuration of the contents of a battery pack. FIG. 42 is a diagram showing an example of an exploded perspective configuration of a battery pack. FIG. 43 is a diagram showing an example of the arrangement of multiple batteries in a battery unit. FIG. 44 is a diagram showing an example of an exploded perspective configuration of a first tab. FIG. 45(A) is a diagram showing an example of a planar configuration of the first tab of FIG. 44. FIG. 45(B) is a diagram showing an example of a configuration in which the planar configuration of the battery and heat absorption member is superimposed on the planar configuration of FIG. 45(A). FIG. 46 is a diagram showing an example of a cross-sectional configuration taken along line A-A of FIG. 45(A). FIG. 47 is a diagram showing an example of a perspective configuration of a second tab. FIG. 48(A) is a diagram showing an example of a planar configuration of the second tab of FIG. 47. FIG. 48(B) is a diagram showing an example of a configuration in which the planar configuration of the battery and heat absorption member is superimposed on the planar configuration of FIG. 48(A). FIG. 49 is a diagram showing an example of a cross-sectional configuration taken along line A-A of FIG. 48(A). Fig. 50 is a diagram illustrating a modified planar configuration of Fig. 45(B). Fig. 51 is a diagram illustrating a modified planar configuration of Fig. 48(B). Fig. 52 is a diagram illustrating a modified perspective configuration of the first tab of Fig. 44. Fig. 53 is a diagram illustrating a modified perspective configuration of the second tab of Fig. 47. Fig. 54 is a diagram illustrating an example perspective configuration of a battery pack according to a fourth embodiment of the present technology. Fig. 55 is a diagram illustrating an example perspective configuration of contents of the battery pack. Fig. 56 is a diagram illustrating an example exploded perspective configuration of the battery pack. Fig. 57 is a diagram illustrating an example arrangement of multiple batteries in a battery unit. Fig. 58 is a diagram illustrating an example exploded perspective configuration of the first tab.FIG. 59 is a diagram illustrating an example of a planar configuration of the first tab of FIG. 58 . FIG. 60 is a diagram illustrating an example of a configuration in which the planar configuration of the battery and heat absorption member is superimposed on the planar configuration of FIG. 59 . FIG. 61 is a diagram illustrating an example of a cross-sectional configuration taken along line A-A of FIG. 59 . FIG. 62 is a diagram illustrating an example of a developed perspective configuration of the second tab. FIG. 63 is a diagram illustrating an example of a planar configuration of the second tab of FIG. 62 . FIG. 64 is a diagram illustrating an example of a configuration in which the planar configuration of the battery and heat absorption member is superimposed on the planar configuration of FIG. 63 . FIG. 65 is a diagram illustrating an example of a cross-sectional configuration taken along line A-A of FIG. 63 . FIG. 66 is a diagram illustrating a modified example of the planar configuration of FIG. 60 . FIG. 67 is a diagram illustrating a modified example of the planar configuration of FIG. 63 . FIG. 68 is a diagram illustrating a modified example of a developed perspective configuration of the first tab of FIG. 58 . FIG. 69 is a diagram illustrating a modified example of a developed perspective configuration of the second tab of FIG. 62 . Fig. 70 is a diagram showing a modified arrangement of multiple batteries in a battery unit according to the first embodiment. Fig. 71 is a diagram showing a modified arrangement of multiple batteries in a battery unit according to the fourth embodiment. Fig. 72 is a diagram showing a modified arrangement of multiple batteries in a battery unit according to the fourth embodiment. Fig. 73 is a diagram showing a modified arrangement of multiple batteries in a battery unit according to the fourth embodiment. Fig. 74 is a diagram showing a modified arrangement of multiple batteries in a battery unit according to the fourth embodiment. Fig. 72 is a diagram showing a modified arrangement of multiple batteries in a battery unit according to the second embodiment.

[0009] Hereinafter, embodiments of the present technology will be described in detail with reference to the drawings.

[0010] First Embodiment First, a battery pack 1 according to a first embodiment of the present technology will be described. Fig. 1 illustrates an example of a perspective configuration of the battery pack 1. Fig. 2 illustrates an example of a perspective configuration of contents contained in the battery pack 1. Fig. 3 illustrates an example of an exploded perspective configuration of the battery pack 1.

[0011] 1 and 2, the battery pack 1 includes an exterior case 10, a battery unit 20 housed in the exterior case 10, and a control board 30. The control board 30 is connected to the positive and negative terminals of the battery unit 20, for example, and has circuits that measure the voltage of the battery and the battery unit, detect the remaining capacity of the battery unit, and measure the current output from the battery unit to detect the presence or absence of an overcurrent.

[0012] 3, the exterior case 10 is composed of a lower case 10a and an upper case 10b. The lower case 10a and the upper case 10b are stacked together to form a storage space for the battery unit 20 and the control board 30. The exterior case 10 (e.g., the lower case 10a) is provided with external terminals 11 connected to the control board 30. The battery unit 20 is connected to the external terminals 11 via the control board 30.

[0013] The battery unit 20 includes a plurality of batteries 40 and two tabs 70a, 70b. The batteries 40 are arranged so that their axial directions are aligned in a common direction (e.g., the X direction in FIG. 3 ). The two tabs 70a, 70b are arranged opposite each other with the plurality of batteries 40 in between. The tab 70a is located at one end of each battery 40, and the tab 70b is located at the other end of each battery 40. The plurality of batteries 40 are electrically connected via the two tabs 70a, 70b. For example, when some of the plurality of batteries 40 are connected in series with the two tabs 70a, 70b, and the plurality of batteries 40 connected in series are referred to as a series unit, the plurality of series units are connected in parallel with the two tabs 70a, 70b. Note that the connection of the plurality of batteries 40 is not limited to the above. The specific configuration of each tab 70a, 70b will be described in detail later.

[0014] Each battery 40 is a cylindrical battery. Each battery 40 is a primary battery or a secondary battery. When each battery 40 is a secondary battery, the type of secondary battery is not particularly limited, but specifically, it may be a lithium-ion secondary battery that obtains battery capacity by utilizing the absorption and release of lithium ions. The following describes a case where each battery 40 is a secondary battery (lithium-ion secondary battery). In other words, the battery pack 1 described below is a power source including multiple secondary batteries. The number of batteries 40 included in the battery unit 20 is 2×n (n is an integer of 2 or greater).

[0015] The battery unit 20 further includes a plurality of heat-absorbing members 50 extending in the axial direction of the batteries 40, and a battery holder 60 that holds 2×n batteries 40 in layers. The plurality of heat-absorbing members 50 are arranged inside the battery holder 60. The number of heat-absorbing members 50 is n-1. The n-1 heat-absorbing members 50 are arranged one at a time in n-1 gaps formed by four adjacent batteries 40 in the 2×n batteries 40. The specific configuration of the heat-absorbing members 50 will be described in detail later.

[0016] Figure 4 shows an example cross-sectional configuration of the battery holder 60. Figure 5 shows an example perspective configuration of the exterior of the battery holder 60. The battery holder 60 is composed of a pair of holders 60a, 60b, as shown in Figures 3 to 5, for example. Both holders 60a, 60b have a common structure.

[0017] Each of the holders 60a and 60b has a side plate 61, as shown in Figures 4 and 5. The side plate 61 of the holder 60a and the side plate 61 of the holder 60b are arranged opposite each other with the batteries 40 between them in the extension direction of the batteries 40 (the direction in which the positive terminals 41 and negative terminals 42, described below, face each other). In the holders 60a and 60b, the side plate 61 has an opening 62 at a location facing the positive terminal 41 and negative terminal 42 of each battery 40. Therefore, the positive terminal 41 or negative terminal 42 is exposed in the opening 62. When the battery unit 20 is viewed in the axial direction of the batteries 40, the side plate 61 covers one end of each heat absorption member 50 and also covers one end of each battery 40 excluding at least a portion of the positive terminal 41 and negative terminal 42. Specifically, the side plate portion 61 covers the first end face 40a and the second end face 40b of each battery 40, excluding the positive electrode terminal 41 and the negative electrode terminal 42. Note that the positive electrode terminal 41 and the negative electrode terminal 42 may be partially covered by the side plate portion 61 as long as they can be electrically connected to the tabs 70a, 70b.

[0018] Each of the holders 60a and 60b further includes a support portion 63 that supports multiple batteries 40 in a tiered configuration with a predetermined gap therebetween, as shown in FIG. 5 . The term "tiered" refers to a state in which an assembly of multiple batteries 40 arranged side by side on a predetermined plane (XY plane) is stacked in a direction perpendicular to the predetermined plane (XY plane). Side plates 61 are connected to both ends of the support portion 63. The support portion 63 supports multiple cylindrical batteries 40 in a tiered configuration with a predetermined gap therebetween. An opening 64 is formed in the support portion 63 at a location surrounded by four adjacent cylindrical batteries 40. The location of the opening 64 in the support portion 63 (the location surrounded by four adjacent cylindrical batteries 40) serves as a storage portion 65 for storing a battery 40. The number of storage portions 65 is n-1.

[0019] The n-1 heat absorption members 50 are arranged in n-1 gaps (accommodating sections 65) surrounded by four adjacent batteries 40 in the 2×n batteries 40. Each heat absorption member 50 contacts the outer periphery of the four batteries 40 via an opening 64. The openings 64 contact the side plate sections 61 of holder 60a and holder 60b, and the heat absorption members 50 contact the side plate sections 61 of holder 60a and holder 60b via the openings 64.

[0020] The battery 40 has a first end surface 40a and a second end surface 40b facing each other, a positive terminal 41 provided on the first end surface 40a, and a negative terminal 42 provided on the second end surface 40b. The battery 40 has, for example, a cylindrical shape in which the first end surface 40a and the second end surface 40b extend in directions facing each other, and the first end surface 40a and the second end surface 40b are each circular. The positive terminal 41 and the negative terminal 42 are made of a metal member.

[0021] 6 shows an example of the arrangement of 2×n batteries 40 held in a battery holder 60 when n=4. Each battery 40 held in the battery holder 60 belongs to one of two groups (a first group G1 and a second group G2). The first group G1 and the second group G2 are conceptually used to classify the 2×n batteries 40 according to their orientation.

[0022] Of the 2×n batteries 40 held in the battery holder 60, n batteries 40X (first batteries) belong to a first group G1. Each battery 40X belonging to the first group G1 is held by the battery holder 60 so that its positive terminal 41 faces the tab 70a in the axial direction of the battery 40X. Of the 2×n batteries 40 held in the battery holder 60, n batteries 40Y (second batteries) different from the n batteries 40X belong to a second group G2. Each battery 40Y belonging to the second group G2 is held by the battery holder 60 so that its positive terminal 41 faces the tab 70b in the axial direction of the battery 40Y.

[0023] Each battery 40X belonging to the first group G1 is arranged in one of a plurality of spatially separated regions R1. Each battery 40Y belonging to the second group G2 is arranged in one of a plurality of spatially separated regions R2. The plurality of regions R1 and the plurality of regions R2 are arranged alternately in a first direction (Y direction in FIG. 6 ) perpendicular to the axial direction of the battery 40 (X direction in FIG. 6 ). Each region R1 extends across each tier of the plurality of batteries 40 arranged in layers within the battery holder 60 in a second direction (Z direction in FIG. 6 ) perpendicular to both the axial direction of the battery 40 (X direction in FIG. 6 ) and the first direction (Y direction in FIG. 6 ). Each region R2 extends across each tier of the plurality of batteries 40 arranged in layers within the battery holder 60 in a second direction (Z direction in FIG. 6 ) perpendicular to both the axial direction of the battery 40 (X direction in FIG. 6 ) and the first direction (Y direction in FIG. 6 ).

[0024] In each layer of the plurality of batteries 40 arranged in layers within the battery holder 60, the plurality of batteries 40X and the plurality of batteries 40Y are arranged alternately one by one in a first direction (Y direction in FIG. 6 ) perpendicular to the axial direction of the batteries 40 (X direction in FIG. 6 ). The n batteries 40X are arranged side by side in a second direction (Z direction in FIG. 6 ) perpendicular to both the axial direction of the batteries 40 (X direction in FIG. 6 ) and the first direction (Y direction in FIG. 6 ). The n batteries 40Y are arranged side by side in the second direction (Z direction in FIG. 6 ) perpendicular to both the axial direction of the batteries 40 (X direction in FIG. 6 ) and the first direction (Y direction in FIG. 6 ).

[0025] FIG. 7(A) shows an example of a perspective configuration of the heat absorption member 50. FIG. 7(B) shows an example of a cross-sectional configuration of the heat absorption member 50 taken along line A-A. The heat absorption member 50 has a shape corresponding to the shape of the housing 65. The heat absorption member 50 has an elongated columnar shape similar to the batteries 40. The heat absorption member 50 contacts the surfaces (outer peripheral surfaces) of four adjacent cylindrical batteries 40, and has a shape corresponding to the shape of the gaps between the four adjacent cylindrical batteries 40. For example, as shown in FIG. 7(B), the cross section of the heat absorption member 50 perpendicular to the extension direction of the heat absorption member 50 has a substantially diamond shape. The extension direction of the heat absorption member 50 is parallel to the extension direction of each battery 40 (the direction in which the positive electrode terminals 41 and negative electrode terminals 42 face each other).

[0026] Here, the four adjacent cylindrical batteries 40 are referred to as the first battery, second battery, third battery, and fourth battery. The heat-absorbing member 50 has an arc-shaped wall W1 extending along the outer circumferential surface of the first battery, an arc-shaped wall W2 extending along the outer circumferential surface of the second battery, an arc-shaped wall W3 extending along the outer circumferential surface of the third battery, and an arc-shaped wall W4 extending along the outer circumferential surface of the fourth battery. The four arc-shaped walls W1 to W4 have a concave shape that conforms to the outer circumferential surfaces of the batteries 40.

[0027] The heat absorbing member 50 includes, for example, a heat absorbing agent 51 and a container 52 that covers the heat absorbing agent 51, as shown in FIGS. 7A and 7B.

[0028] The heat-absorbing agent 51 is made of, for example, a liquid containing water or a hydrogel. When using a hydrogel as the heat-absorbing agent 51, it is preferable to use a synthetic polymer gel. Examples of materials for the synthetic polymer gel include sodium polyacrylate (PNaAA), polyvinyl alcohol (PVA), polyhydroxyethyl methacrylate (PHE-MA), and silicone hydrogel.

[0029] The container 52 covers the heat-absorbing agent 51. The container 52 may be formed, for example, by heating and molding the heat-absorbing agent 51 and the resin layer while the heat-absorbing agent 51 is covered with the resin layer. The container 52 may include a soft sheet material made of a thermoplastic material. The container 52 may include, for example, a resin layer as the soft sheet material. The resin layer may be made of a resin material such as polyethylene, polystyrene, polypropylene, or polycarbonate. The container 52 may include, for example, a laminated film. The laminated film is, for example, a laminated sheet in which a metal layer is sandwiched between two resin layers. In this case, the container 52 includes two resin layers as the soft sheet material. Each resin layer may be made of a resin material such as polyethylene, polystyrene, polypropylene, or polycarbonate. The metal layer may be made of a metal foil such as aluminum foil.

[0030] Next, the specific configuration of the tabs 70a and 70b will be described.

[0031] Figure 8 shows an example of an exploded perspective configuration of the tab 70a. The tab 70a is a tab (first tab) that connects to terminals on one end of 2xn batteries 40. For example, as shown in Figure 8, the tab 70a is a tab module having power extraction tab components 71 and 72 and an intermediate connection tab component 73. The power extraction tab components 71 and 72 and the intermediate connection tab component 73 are made of metal members.

[0032] The power supply extraction tab component 72 is connected to the positive electrode terminals 41 of a plurality of batteries 40X (third batteries) that are part of the n batteries 40X belonging to the first group G1. The plurality of batteries 40X connected to the power supply extraction tab component 72 are arranged in region R1. The power supply extraction tab component 72 has a plurality of protrusions 72A that protrude toward the batteries 40. The plurality of protrusions 72A are provided in positions that face the positive electrode terminals 41 of the plurality of batteries 40X arranged in region R1. Each protrusion 72A is electrically connected to the corresponding positive electrode terminal 41 via a conductive material such as solder.

[0033] The power supply extraction tab component 71 is connected to the negative electrode terminals 42 of a plurality of batteries 40Y (fourth batteries) that are part of the n batteries 40Y belonging to the second group G2. The plurality of batteries 40Y connected to the power supply extraction tab component 71 are arranged in region R2. The power supply extraction tab component 71 has a plurality of protrusions 71A that protrude toward the batteries 40. The plurality of protrusions 71A are provided in positions facing the negative electrode terminals 42 of the plurality of batteries 40Y arranged in region R2. Each protrusion 71A is electrically connected to the corresponding negative electrode terminal 42 via a conductive material such as solder.

[0034] The intermediate connection tab part 73 is connected to the positive terminals 41 of the batteries 40X (fifth batteries) other than the third batteries among the n batteries 40X belonging to the first group G1. The intermediate connection tab part 73 is also connected to the negative terminals 42 of the batteries 40Y (sixth batteries) other than the fourth batteries among the n batteries 40Y belonging to the second group G2. The intermediate connection tab part 73 has multiple protrusions 73A protruding toward the batteries 40. The multiple protrusions 73A are provided at positions facing the positive terminals 41 of the batteries 40X arranged in region R1 and at positions facing the negative terminals 42 of the batteries 40Y arranged in region R2. Of the multiple protrusions 73A, each protrusion 73A provided at a position facing the positive terminal 41 is electrically connected to the corresponding positive terminal 41 via a conductive material such as solder. Of the plurality of protrusions 73A, each protrusion 73A provided at a position facing a negative electrode terminal 42 is electrically connected to the corresponding negative electrode terminal 42 via a conductive material such as solder.

[0035] The tab 70a further includes insulating layers 74, 75, and 76, as shown in FIG. 8 . The insulating layer 74 is disposed between the power extraction tab components 71 and 72 and the plurality of batteries 40. The insulating layer 74 has a plurality of openings 74A at positions facing the plurality of protrusions 71A, the plurality of protrusions 72A, and the plurality of protrusions 73A. The power extraction tab component 71 is electrically connected to the negative electrode terminals 42 of the plurality of batteries 40Y facing the power extraction tab component 71 via the plurality of openings 74A in the insulating layer 74. The power extraction tab component 72 is electrically connected to the positive electrode terminals 41 of the plurality of batteries 40X facing the power extraction tab component 72 via the plurality of openings 74A in the insulating layer 74.

[0036] The insulating layer 75 is disposed between the power supply tab parts 71, 72 and the intermediate connection tab part 73, enabling the power supply tab parts 71, 72 and the intermediate connection tab part 73 to be insulated and separated from each other. The insulating layer 75 has a plurality of openings 75A at positions facing at least a plurality of the protrusions 71A, 72A, and 73A among the plurality of protrusions 71A, 72A, and 73A. Figure 8 illustrates an example in which the insulating layer 75 has a plurality of openings 75A at positions facing the plurality of protrusions 71A, 72A, and 73A. The intermediate connection tab part 73 is electrically connected to the positive terminals 41 of the plurality of batteries 40X and the negative terminals 42 of the plurality of batteries 40Y facing the intermediate connection tab part 73 via the plurality of openings 74A in the insulating layer 74 and the plurality of openings 75A in the insulating layer 75.

[0037] The insulating layer 76 is disposed between the intermediate connection tab component 73 and the inner wall of the outer case 10. For example, as shown in FIG. 8 , the insulating layer 76 may have multiple openings 76A at positions facing the multiple protrusions 71A, 72A, and 73A. The openings 76A improve the ease of connecting the protrusions (71A, 72A, 73A) of the tab components (power supply tab components 71, 72 and intermediate connection tab component 73) to the batteries 40 facing the protrusions 71A, 72A, and 73A. The insulating layer 76 may be formed, for example, from a sheet without openings. The insulating layers 75 and 76 may have the same configuration as the insulating layer 74. The insulating layers 74, 75, and 76 may be formed, for example, from a resin sheet. The insulating layers 74 , 75 , 76 are attached to a resin sheet by, for example, heat fusion or the like, and serve to fix the relative positional relationship between the power supply take-out tab parts 71 , 72 and the intermediate connection tab part 73 .

[0038] FIG. 9 shows an example of the planar configuration of the power take-out tab parts 71, 72, and intermediate connection tab part 73 included in the tab 70a. In the tab 70a, a portion of the power take-out tab part 71 and a portion of the intermediate connection tab part 73 overlap each other. That is, the tab 70a has an overlapping portion 78 where the power take-out tab part 71 and the intermediate connection tab part 73 overlap each other. For example, as shown in FIG. 10 , the overlapping portion 78 is located in a position facing the heat absorption member 50 provided between the multiple batteries 40 connected to the power take-out tab part 71 and the multiple batteries 40 connected to the intermediate connection tab part 73 and closer to the power take-out tab part 71. In the tab 70a, a portion of the power take-out tab part 72 and a portion of the intermediate connection tab part 73 overlap each other. That is, the tab 70a has an overlapping portion 77 where the power take-out tab part 72 and the intermediate connection tab part 73 overlap each other. 10, the overlap portion 77 is disposed in a position facing the heat absorption member 50 provided between the plurality of batteries 40 connected to the power take-out tab part 72 and the plurality of batteries 40 connected to the intermediate connection tab part 73 and closer to the power take-out tab part 72. The tabs 70a (specifically, the power take-out tab parts 71, 72 and the intermediate connection tab part 73) are formed to cover one end of each heat absorption member 50 and one end of each battery 40 when the battery unit 20 is viewed in the axial direction of the batteries 40, for example, as shown in FIG.

[0039] Fig. 11 shows an example of a cross-sectional configuration taken along line A-A in Fig. 9. For example, as shown in Fig. 11, the insulating layers 74, 75 are formed so as to sandwich the portions of the power take-out tab parts 71, 72 other than the protrusions 71A, 72A. For example, as shown in Fig. 11, the insulating layers 75, 76 are formed so as to sandwich the portions of the intermediate connection tab part 73 other than the protrusion 73A. In the tab 70a, the tops of the protrusions 71A, 72A, and 73A are arranged in the same plane.

[0040] Figure 12 shows an example of an exploded perspective configuration of the tab 70b. The tab 70b is a tab (second tab) that connects to the terminals on the other ends of the 2 x n batteries 40. As shown in Figure 12, the tab 70b is, for example, a tab module having intermediate connection tab components 81 and 82. The intermediate connection tab components 81 and 82 are made of metal.

[0041] The intermediate connection tab part 81 is connected to the negative terminals 42 of a plurality of batteries 40X (third batteries) that are part of the n batteries 40X belonging to the first group G1. The intermediate connection tab part 81 is also connected to the positive terminals 41 of a plurality of batteries 40Y (sixth batteries) other than the plurality of fourth batteries among the n batteries 40Y belonging to the second group G2. The intermediate connection tab part 81 has a plurality of protrusions 81A that protrude toward the batteries 40. The protrusions 81A are provided at positions facing the negative terminals 42 of the batteries 40X arranged in region R1 and at positions facing the positive terminals 41 of the batteries 40Y arranged in region R2. Of the plurality of protrusions 81A, each protrusion 81A that is provided at a position facing the negative terminal 42 is electrically connected to the corresponding negative terminal 42 via a conductive material such as solder. Of the plurality of protrusions 81A, each protrusion 81A provided at a position facing a positive electrode terminal 41 is electrically connected to the corresponding positive electrode terminal 41 via a conductive material such as solder.

[0042] The intermediate connection tab part 82 is connected to the positive terminals 41 of a plurality of batteries 40Y (fourth batteries) that are part of the n batteries 40Y belonging to the second group G2. The intermediate connection tab part 82 is also connected to the negative terminals 42 of a plurality of batteries 40Y (fifth batteries) other than the third batteries among the n batteries 40Y belonging to the second group G2. The intermediate connection tab part 82 has a plurality of protrusions 82A that protrude toward the batteries 40. The protrusions 82A are provided at positions facing the negative terminals 42 of the batteries 40X arranged in region R1 and at positions facing the positive terminals 41 of the batteries 40Y arranged in region R2. Of the plurality of protrusions 82A, each protrusion 82A that is provided at a position facing the negative terminal 42 is electrically connected to the corresponding negative terminal 42 via a conductive material such as solder. Of the plurality of protrusions 82A, each protrusion 82A provided at a position facing a positive electrode terminal 41 is electrically connected to the corresponding positive electrode terminal 41 via a conductive material such as solder.

[0043] 12 , the tab 70b further includes insulating layers 83, 84, and 85. The insulating layer 83 is disposed between the intermediate connection tab part 82 and the plurality of batteries 40. The insulating layer 83 has a plurality of openings 83A at positions facing the plurality of protrusions 82A. The intermediate connection tab part 82 is electrically connected to the negative electrode terminals 42 of the plurality of batteries 40X and the positive electrode terminals 41 of the plurality of batteries 40Y facing the intermediate connection tab part 82 via the plurality of openings 83A in the insulating layer 83.

[0044] The insulating layer 84 is disposed between the intermediate connection tab part 81 and the intermediate connection tab part 82, enabling the intermediate connection tab part 81 and the intermediate connection tab part 82 to be insulated and separated from each other. The insulating layer 84 has a plurality of openings 84A at positions facing at least a plurality of the protrusions 81A and 82A. Figure 11 illustrates an example of the insulating layer 84 having a plurality of openings 84A at positions facing the protrusions 81A and 82A. The intermediate connection tab part 81 is electrically connected to the negative terminals 42 of the plurality of batteries 40X and the positive terminals 41 of the plurality of batteries 40Y facing the intermediate connection tab part 81 via the plurality of openings 84A in the insulating layer 84.

[0045] The insulating layer 85 is disposed between the intermediate connection tab part 81 and the inner wall of the outer case 10. For example, as shown in FIG. 12 , the insulating layer 85 may have multiple openings 85A at positions facing the multiple protrusions 81A. The openings 85A improve the ease of connecting the protrusions (protrusions 81A, 82A) of the tab parts (intermediate connection tab parts 81, 82) to the batteries 40 facing the protrusions 81A, 82A. The insulating layer 85 may be formed, for example, from a sheet without openings. The insulating layers 83, 84, and 85 are formed, for example, from a resin sheet. The insulating layers 83, 84, and 85 are bonded to the resin sheet by, for example, heat fusion bonding, and serve to fix the relative positions of the intermediate connection tab parts 81 and 82.

[0046] FIG. 13 shows an example of the planar configuration of the intermediate connection tab parts 81 and 82 included in the tab 70b. In the tab 70b, a portion of the intermediate connection tab part 81 and a portion of the intermediate connection tab part 82 overlap each other. That is, the tab 70b has an overlapping portion 86 where the intermediate connection tab parts 81 and 82 overlap each other. For example, as shown in FIG. 14 , the overlapping portion 86 is positioned to face a heat absorption member 50 provided between the plurality of batteries 40 connected to the intermediate connection tab part 81 and closer to the intermediate connection tab part 82 and the plurality of batteries 40 connected to the intermediate connection tab part 82 and closer to the intermediate connection tab part 81. For example, as shown in FIG. 14 , the tab 70b (specifically, the intermediate connection tab parts 81 and 82) is formed to cover one end of each heat absorption member 50 and one end of each battery 40 when the battery unit 20 is viewed in the axial direction of the batteries 40.

[0047] Fig. 15 shows an example of a cross-sectional configuration taken along line A-A in Fig. 13. For example, as shown in Fig. 15, the insulating layers 83 and 84 are formed so as to sandwich the intermediate connection tab part 82 except for the protruding part 82A. For example, as shown in Fig. 15, the insulating layers 84 and 85 are formed so as to sandwich the intermediate connection tab part 81 except for the protruding part 81A. In the tab 70b, the tops of the protruding parts 81A and 82A are arranged in the same plane.

[0048] In the tab 70a, for example, as shown in FIG. 9, the power supply take-out tab part 71 has a hook 71B, the power supply take-out tab part 72 has a hook 72B, and the intermediate connection tab part 73 has a hook 73B. In the tab 70b, for example, as shown in FIG. 13, the intermediate connection tab part 81 has a hook 81B, and the intermediate connection tab part 82 has a hook 82B. The hooks 71B, 72B, and 73B can be engaged with the slits 31 of the control board 30 to fix the tab 70a to the control board 30. The hooks 81B and 82B can be engaged with the slits 31 of the control board 30 to fix the tab 70b to the control board 30. Hereinafter, the hooks 71B, 72B, 73B, 81B, and 82B will be collectively referred to as hooks FK.

[0049] 16 shows the procedure for engaging the hooks FK provided on the tabs 70a and 70b with the control board 30. First, the hooks FK are inserted into the slits 31 of the control board 30. Next, the portions of the hooks FK that are exposed from the slits 31 are bent. This causes the hooks FK to engage with the slits 31 of the control board 30.

[0050] Next, the effects of the battery pack 1 will be described.

[0051] In this embodiment, tab 70a is formed to cover one end of each heat absorption member 50 when the battery unit 20 is viewed from the axial direction of the batteries 40. Furthermore, tab 70b is formed to cover the other end of each heat absorption member 50 when the battery unit 20 is viewed from the axial direction of the batteries 40. As a result, when the housing 52 is torn open and the heat absorption agent 51 leaks out, the tabs 70a and 70b act as walls to keep the heat absorption agent 51 within the battery unit 20. This makes it possible to prevent a decrease in the heat absorption effect of the heat absorption agent 51. Therefore, it is possible to provide a battery pack 1 having a structure that provides a high heat absorption effect of the heat absorption agent 51.

[0052] In this embodiment, when the battery unit 20 is viewed from the axial direction of the batteries 40, the tab 70a is formed to cover one end of each heat absorption member 50 and one end of each battery 40. Furthermore, when the battery unit 20 is viewed from the axial direction of the batteries 40, the tab 70b is formed to cover the other end of each heat absorption member 50 and the other end of each battery 40. As a result, when the housing 52 is torn open and the heat absorption agent 51 leaks out, the tabs 70a and 70b act as walls to keep the heat absorption agent 51 within the battery unit 20. This prevents a decrease in the heat absorption effect of the heat absorption agent 51. Therefore, a battery pack 1 having a structure that provides a high heat absorption effect due to the heat absorption agent 51 can be provided.

[0053] In this embodiment, when the battery unit 20 is viewed in the axial direction of the batteries 40, the side plate 61 of the holder 60a covers one end of each heat absorption member 50 and also covers one end of each battery 40 excluding at least a portion of the positive terminal 41 and the negative terminal 42. Furthermore, when the battery unit 20 is viewed in the axial direction of the batteries 40, the side plate 61 of the holder 60b covers the other end of each heat absorption member 50 and also covers the other end of each battery 40 excluding at least a portion of the positive terminal 41 and the negative terminal 42. This allows the side plate 61 to function as a wall to contain the heat absorption agent 51 within the battery unit 20 when the housing 52 is torn open and the heat absorption agent 51 leaks out. This prevents a decrease in the heat absorption effect of the heat absorption agent 51. Therefore, a battery pack 1 having a structure that provides a high heat absorption effect due to the heat absorption agent 51 can be provided.

[0054] In this embodiment, the tab 70a is a tab module having overlapping portions 77 and 78 where the power take-out tab parts 71 and 72 and the intermediate connection tab part 73 overlap each other. Furthermore, the tab 70b is a tab module having an overlapping portion 86 where the intermediate connection tab parts 81 and 82 overlap each other. The overlapping portion 77 is located in a position facing the heat absorption member 50 provided between the plurality of batteries 40 connected to the power take-out tab part 71 and the plurality of batteries 40 connected to the intermediate connection tab part 73 and closer to the power take-out tab part 71. The overlapping portion 78 is located in a position facing the heat absorption member 50 provided between the plurality of batteries 40 connected to the power take-out tab part 72 and the plurality of batteries 40 connected to the intermediate connection tab part 73 and closer to the power take-out tab part 72. The overlap portion 86 is positioned to face the heat absorption member 50 provided between the plurality of batteries 40 connected to the intermediate connection tab part 81 and closer to the intermediate connection tab part 82 and the plurality of batteries 40 connected to the intermediate connection tab part 82 and closer to the intermediate connection tab part 81. As a result, when the housing 52 is torn open and the heat absorption agent 51 leaks out, the tab 70a (specifically, the power extraction tab parts 71, 72 and the intermediate connection tab part 73) and the tab 70b (specifically, the intermediate connection tab parts 81, 82) act as walls to contain the heat absorption agent 51 within the battery unit 20. This prevents a decrease in the heat absorption effect of the heat absorption agent 51. Therefore, a battery pack 1 having a structure that enhances the heat absorption effect of the heat absorption agent 51 can be provided.

[0055] In this embodiment, an insulating layer 75 is provided to insulate and separate the power supply tab parts 71, 72 from the intermediate connection tab part 73, and an insulating layer 84 is provided to insulate and separate the intermediate connection tab parts 81 and 82. This allows the tab 70a to be integrally formed without impairing the electrical function of the tab 70a, and the tab 70b to be integrally formed without impairing the electrical function of the tab 70b.

[0056] In this embodiment, hooks 71B, 72B, and 73B are provided on tab 70a, and hooks 81B and 82B are provided on tab 70b, which prevents tabs 70a and 70b from falling off battery unit 20 due to the force of gas ejection in the event of an abnormality, and allows leaked heat-absorbing agent 51 to be retained.

[0057] Next, a modified example of the battery pack 1 will be described.

[0058] 17 , for example, multiple regions R1 may be combined into one region R1, and multiple regions R2 may be combined into one region R2. In this case, all of the batteries 40X in the battery holder 60 (all of the batteries 40X belonging to the first group G1) are arranged in the single combined region R1, and all of the batteries 40Y in the battery holder 60 (all of the batteries 40Y belonging to the second group G2) are arranged in the single combined region R2.

[0059] In this modification, tab 70c shown in Fig. 18 is provided instead of tab 70a. In this modification, intermediate connection tab part 81 is used as a power supply take-out tab part in tab 70b, and intermediate connection tab part 82 is used as a power supply take-out tab part. Tab 70c is a tab (first tab) that connects to terminals on one end of 2xn batteries 40. Tab 70c is made of a metal member.

[0060] The tabs 70c are intermediate connection tab components 79 connected to the positive electrode terminals 41 of the n batteries 40X belonging to the first group G1 and the negative electrode terminals 42 of the n batteries 40Y belonging to the second group G2. The tabs 70a (specifically, the intermediate connection tab components 79) are formed to cover one end of each heat absorption member 50 and one end of each battery 40 when the battery unit 20 is viewed from the axial direction of the batteries 40.

[0061] The intermediate connection tab component 79 has multiple protrusions 79A that protrude toward the batteries 40. The multiple protrusions 79A are provided at positions facing the positive electrode terminals 41 of the n batteries 40X belonging to the first group G1 and at positions facing the negative electrode terminals 42 of the n batteries 40Y belonging to the second group G2. Of the multiple protrusions 79A, each protrusion 79A provided at a position facing the positive electrode terminal 41 is electrically connected to the corresponding positive electrode terminal 41 via a conductive material such as solder. Of the multiple protrusions 79A, each protrusion 79A provided at a position facing the negative electrode terminal 42 is electrically connected to the corresponding negative electrode terminal 42 via a conductive material such as solder.

[0062] In this modification, tab 70c is provided instead of tab 70a. Even in this case, when housing 52 is torn open and heat-absorbing agent 51 leaks out, tabs 70a and 70c act as walls to keep heat-absorbing agent 51 contained within battery unit 20. This prevents a decrease in the heat-absorbing effect of heat-absorbing agent 51. Therefore, a battery pack 1 having a structure that enhances the heat-absorbing effect of heat-absorbing agent 51 can be provided.

[0063] (Variation 1-2) In the first embodiment, the tabs 70a (specifically, the power supply tab components 71, 72 and the intermediate connection tab component 73) are formed so as to cover one end of each heat absorption member 50 when the battery unit 20 is viewed from the axial direction of the batteries 40, as shown in Fig. 19, but may be formed so as to expose a portion of one end of each battery 40. Also, in the first embodiment, the tabs 70b (specifically, the intermediate connection tab components 81, 82) are formed so as to cover one end of each heat absorption member 50 when the battery unit 20 is viewed from the axial direction of the batteries 40, as shown in Fig. 20, but may be formed so as to expose a portion of one end of each battery 40.

[0064] Even in this case, when the housing 52 is torn open and the heat-absorbing agent 51 leaks out, the tabs 70a and 70b act as walls to keep the heat-absorbing agent 51 inside the battery unit 20. This prevents a decrease in the heat-absorbing effect of the heat-absorbing agent 51. Therefore, it is possible to provide a battery pack 1 having a structure that enhances the heat-absorbing effect of the heat-absorbing agent 51.

[0065] (Variation 1-3) In the first embodiment and Variation 1-2, the overlapping portions 77 and 78 may not be positioned opposite the heat-absorbing members 50, but may be positioned not opposite the other ends of the heat-absorbing members 50, as shown in FIG. 21 . Also, in the first embodiment and Variation 1-2, the overlapping portion 86 may not be positioned opposite the heat-absorbing members 50, but may be positioned not opposite the other ends of the heat-absorbing members 50, as shown in FIG. 22 . Even in this case, as in the first embodiment and Variation 1-2, it is possible to suppress a decrease in the heat-absorbing effect of the heat-absorbing agent 51. Therefore, it is possible to provide a battery pack 1 having a structure that enhances the heat-absorbing effect of the heat-absorbing agent 51.

[0066] (Variation 1-4) In the first embodiment and variations 1-2 and 1-3, the tab 70a may have the power takeoff tab parts 71 and 72 and the intermediate connection tab part 73 arranged in the same plane, as shown in Figures 23 and 24, and have insulating layers 91 and 92 in the gaps between the ends of the power takeoff tab parts 71 and 72 and the end of the intermediate connection tab part 73. Also, in the first embodiment and variations 1-2 and 1-3, the tab 70b may have the intermediate connection tab parts 81 and 82 arranged in the same plane, as shown in Figures 25 and 26, and have insulating layers 93 in the gaps between the ends of the intermediate connection tab parts 81 and 82.

[0067] The insulating layers 91, 92, and 93 are made of, for example, a resin material. The insulating layer 91 is formed to connect an end of the power take-out tab part 71 to an end of the intermediate connection tab part 73. The insulating layer 92 is formed to connect an end of the power take-out tab part 72 to an end of the intermediate connection tab part 73. The insulating layer 93 is formed to connect an end of the intermediate connection tab part 81 to an end of the intermediate connection tab part 82.

[0068] Even in this case, when the housing 52 is torn open and the heat-absorbing agent 51 leaks out, the tabs 70a and 70b act as walls to keep the heat-absorbing agent 51 inside the battery unit 20. This prevents a decrease in the heat-absorbing effect of the heat-absorbing agent 51. Therefore, it is possible to provide a battery pack 1 having a structure that enhances the heat-absorbing effect of the heat-absorbing agent 51.

[0069] Second Embodiment Next, a battery pack 2 according to a second embodiment of the present technology will be described. Fig. 27 illustrates an example of a perspective configuration of the battery pack 2. Fig. 28 illustrates an example of a perspective configuration of contents of the battery pack 2. Fig. 29 illustrates an example of an exploded perspective configuration of the battery pack 2.

[0070] 27 and 28, the battery pack 2 includes an exterior case 110, a battery unit 120 housed in the exterior case 110, and a control board 130. The control board 130 is connected to the positive and negative terminals of the battery unit 120, for example, and has circuits that measure the voltage of the battery and the battery unit, detect the remaining capacity of the battery unit, and measure the current output from the battery unit to detect the presence or absence of an overcurrent.

[0071] 29 , the exterior case 110 is composed of a lower case 110a and an upper lid 110b. The lower case 110a and the upper lid 110b are stacked together to form a storage space for accommodating the battery unit 120 and the control board 130. The exterior case 110 (e.g., the lower case 110a) is provided with external terminals 111 connected to the control board 130. The battery unit 120 is connected to the external terminals 111 via the control board 130.

[0072] The battery unit 120 has two batteries 40 and two tabs 170a, 170b. The two batteries 40 are arranged so that their axial directions face a common direction (e.g., the X direction in FIG. 29 ). The two batteries 40 are arranged side by side on a predetermined plane (the XY plane). The two tabs 170a, 170b are arranged opposite each other with the two batteries 40 between them. The tab 170a is arranged on one end of each battery 40, and the tab 170b is arranged on the other end of each battery 40. The two batteries 40 are electrically connected via the two tabs 170a, 170b. For example, the two batteries 40 are connected in series with each other via the two tabs 170a, 170b. The specific configuration of each tab 170a, 170b will be described in detail later.

[0073] The battery unit 120 further includes a heat absorption member 150 extending in the axial direction of the batteries 40, and a battery holder 160 that holds two batteries 40. One heat absorption member 150 is disposed within the battery holder 160. One heat absorption member 150 is disposed in a triangular prism-shaped gap formed between two adjacent batteries 40. The heat absorption member 150 has a common configuration with the heat absorption member 50, except that its cross section is approximately triangular.

[0074] The battery holder 160 is composed of a pair of holders 160a and 160b, as shown in Figure 29. The holders 160a and 160b have the same structure as the holders 60a and 60b, except that they hold two batteries 40.

[0075] Next, the specific configuration of the tabs 170a and 170b will be described.

[0076] Fig. 30 shows an example of an exploded perspective configuration of the tab 170a. As shown in Fig. 30, the tab 170a is, for example, a tab module having power supply take-out tab parts 171 and 172. The power supply take-out tab parts 171 and 172 are made of metal members.

[0077] The power supply take-out tab part 172 is connected to the positive electrode terminal 41 of one of the two batteries 40. The power supply take-out tab part 172 has a protrusion 172A that protrudes toward the battery 40. The protrusion 172A is provided in a position facing the positive electrode terminal 41 of one of the two batteries 40. The protrusion 172A is electrically connected to the corresponding positive electrode terminal 41 via a conductive material such as solder.

[0078] The power supply take-out tab part 171 is connected to the negative electrode terminal 42 of the other of the two batteries 40. The power supply take-out tab part 171 has a protrusion 171A that protrudes toward the battery 40. The protrusion 171A is provided in a position facing the negative electrode terminal 42 of the other of the two batteries 40. The protrusion 171A is electrically connected to the corresponding negative electrode terminal 42 via a conductive material such as solder.

[0079] 30, the tab 170a further has an insulating layer 173. The insulating layer 173 is disposed between the power supply take-out tab part 171 and the power supply take-out tab part 172. The insulating layer 173 is formed, for example, from a resin sheet without any openings.

[0080] FIG. 31(A) shows an example of the planar configuration of the power supply extracting tab components 171 and 172 included in the tab 170a. In the tab 170a, a portion of the power supply extracting tab component 171 and a portion of the power supply extracting tab component 172 overlap each other. That is, the tab 170a has an overlapping portion 174 where the power supply extracting tab component 171 and the power supply extracting tab component 172 overlap each other. For example, as shown in FIG. 31(B), the overlapping portion 174 is positioned opposite the heat absorption member 150 that is positioned between the battery 40 connected to the power supply extracting tab component 171 and the battery 40 connected to the power supply extracting tab component 172. For example, as shown in FIG. 31(B), the tab 170a (specifically, the power supply extracting tab components 171 and 172) is formed to cover one end of the heat absorption member 150 and one end of each battery 40 when the battery unit 20 is viewed in the axial direction of the batteries 40.

[0081] Fig. 32 shows an example of a cross-sectional configuration taken along line A-A in Fig. 31(A) . For example, as shown in Fig. 32 , the insulating layer 173 is formed so as to be sandwiched between the portions of the power take-out tab parts 171 and 172 that correspond to the overlap portion 174.

[0082] Figure 33 shows an example of the developed perspective configuration of the tab 170b. The tab 170b is a tab that connects to the terminals on the other ends of the two batteries 40. For example, as shown in Figure 33, the tab 170b is made of an intermediate connection tab part 181. The intermediate connection tab part 181 is made of a metal member. The tab 170b (specifically, the intermediate connection tab part 181) is formed so as to cover one end of the heat absorption member 50 and one end of each battery 40 when the battery unit 120 is viewed in the axial direction of the batteries 40.

[0083] The intermediate connection tab part 181 is connected to the negative terminal 42 of one of the two batteries 40 and the positive terminal 41 of the other of the two batteries 40. The intermediate connection tab part 181 has two protrusions 181A protruding toward the batteries 40. The two protrusions 181A are provided at a position facing the negative terminal 42 of one of the two batteries 40 and a position facing the positive terminal 41 of the other of the two batteries 40. Of the two protrusions 181A, the protrusion 181A provided at a position facing the negative terminal 42 is electrically connected to the corresponding negative terminal 42 via a conductive material such as solder. Of the two protrusions 181A, the protrusion 181A provided at a position facing the positive terminal 41 is electrically connected to the corresponding positive terminal 41 via a conductive material such as solder.

[0084] In the tab 170a, for example, as shown in FIG. 31A, the power supply take-out tab part 171 has a hook 171B, and the power supply take-out tab part 172 has a hook 172B. In the tab 170b, for example, as shown in FIG. 33, the intermediate connection tab part 181 has a hook 181B. The hooks 171B, 172B can be engaged with the slits 31 of the control board 30 to fix the tab 170a to the control board 30. The hook 181B can be engaged with the slits 31 of the control board 30 to fix the tab 170b to the control board 30.

[0085] Next, the effects of the battery pack 2 will be described.

[0086] In this embodiment, tab 170a is formed to cover one end of heat absorption member 150 when battery unit 120 is viewed from the axial direction of batteries 40. Furthermore, tab 170b is formed to cover the other end of heat absorption member 150 when battery unit 120 is viewed from the axial direction of batteries 40. As a result, when housing 52 is torn open and heat absorption agent 51 leaks out, tabs 170a and 170b act as walls to keep heat absorption agent 51 within battery unit 120. This makes it possible to prevent a decrease in the heat absorption effect of heat absorption agent 51. Therefore, a battery pack 2 having a structure that provides a high heat absorption effect of heat absorption agent 51 can be provided.

[0087] In this embodiment, the tab 170a is formed to cover one end of the heat absorption member 150 and one end of each battery 40 when the battery unit 120 is viewed from the axial direction of the batteries 40. Furthermore, the tab 170b is formed to cover the other end of the heat absorption member 150 and the other end of each battery 40 when the battery unit 120 is viewed from the axial direction of the batteries 40. As a result, when the housing 52 is torn open and the heat absorption agent 51 leaks out, the tabs 170a and 170b act as walls to keep the heat absorption agent 51 within the battery unit 120. This prevents a decrease in the heat absorption effect of the heat absorption agent 51. Therefore, a battery pack 2 having a structure that provides a high heat absorption effect due to the heat absorption agent 51 can be provided.

[0088] In this embodiment, when the battery unit 120 is viewed in the axial direction of the batteries 40, the side plate 61 of the holder 160a covers one end of the heat absorption member 150 and also covers one end of each battery 40, excluding at least a portion of the positive terminal 41 and the negative terminal 42. Furthermore, when the battery unit 120 is viewed in the axial direction of the batteries 40, the side plate 61 of the holder 160b covers one end of the heat absorption member 150 and also covers one end of each battery 40, excluding at least a portion of the positive terminal 41 and the negative terminal 42. This allows the side plate 61 to function as a wall to contain the heat absorption agent 51 within the battery unit 120, even if the housing 52 is torn open and the heat absorption agent 51 leaks out. This prevents a decrease in the heat absorption effect of the heat absorption agent 51. Therefore, a battery pack 2 having a structure that provides a high heat absorption effect due to the heat absorption agent 51 can be provided.

[0089] In this embodiment, the tab 170a is a tab module having an overlapping portion 174 where the power supply extraction tab part 171 and the power supply extraction tab part 172 overlap each other. The overlapping portion 174 is positioned opposite the heat absorption member 150, which is disposed between the battery 40 connected to the power supply extraction tab part 171 and the battery 40 connected to the power supply extraction tab part 172. This allows the tab 170a (specifically, the power supply extraction tab parts 171 and 172) and the tab 170b (specifically, the intermediate connection tab part 181) to function as a wall to contain the heat absorption agent 51 within the battery unit 120 when the housing 52 is torn open and the heat absorption agent 51 leaks out. This prevents a decrease in the heat absorption effect of the heat absorption agent 51. Therefore, a battery pack 2 having a structure that enhances the heat absorption effect of the heat absorption agent 51 can be provided.

[0090] In this embodiment, an insulating layer 173 is provided to insulate and separate the power supply take-out tab parts 171 and 172. This allows the tabs 170a to be integrally formed without impairing the electrical function of the tabs 170a.

[0091] In this embodiment, hooks 171B and 172B are provided on tab 170a, and hook 181B is provided on tab 170b, which prevents tabs 170a and 170b from falling off battery unit 120 when housing 52 is torn open and heat-absorbing agent 51 leaks out.

[0092] Next, a modified example of the battery pack 2 will be described.

[0093] (Variation 2-1) In the second embodiment, the tab 170a (specifically, the power supply tab components 171, 172) may be formed to cover one end of the heat absorption member 150 when the battery unit 120 is viewed from the axial direction of the batteries 40, as shown in Figure 34, but may be formed to expose a portion of one end of each battery 40. Also, in the second embodiment, the tab 170b (specifically, the intermediate connection tab component 181) may be formed to cover the other end of the heat absorption member 150 when the battery unit 120 is viewed from the axial direction of the batteries 40, but may be formed to expose a portion of the other end of each battery 40.

[0094] Even in this case, when the housing 52 is torn open and the heat-absorbing agent 51 leaks out, the tabs 170a and 170b act as walls to keep the heat-absorbing agent 51 inside the battery unit 120. This prevents a decrease in the heat-absorbing effect of the heat-absorbing agent 51. Therefore, it is possible to provide a battery pack 2 having a structure that enhances the heat-absorbing effect of the heat-absorbing agent 51.

[0095] (Variation 2-2) In the second embodiment and variation 2-1, the overlap portion 174 may be arranged in a position not facing the other end of the heat absorption member 150, as shown in Fig. 35, for example. Even in this case, as in the second embodiment and variation 2-1, it is possible to suppress a decrease in the heat absorption effect of the heat absorption agent 51. Therefore, it is possible to provide a battery pack 2 having a structure in which the heat absorption effect of the heat absorption agent 51 is high.

[0096] (Variation 2-3) In the second embodiment and variations 2-1 and 2-2, the tab 170a may further include insulating layers 175, 176, for example, as shown in FIG. 36 . The insulating layer 175 is disposed between the power supply take-out tab part 172 and the two batteries 40. The insulating layer 175 has two openings 174A at positions facing the protrusions 171A and 172A. The power supply take-out tab part 171 is electrically connected to the negative terminal 42 of the battery 40 facing the power supply take-out tab part 171 through the opening 175A of the insulating layer 175. The power supply take-out tab part 172 is electrically connected to the positive terminal 41 of the battery 40 facing the power supply take-out tab part 172 through the opening 175A of the insulating layer 175.

[0097] The insulating layer 176 is disposed between the power supply tab component 171 and the inner wall of the exterior case 10. For example, as shown in FIG. 36 , the insulating layer 176 may have two openings 176A at positions facing the protrusions 171A and 172A. The openings 176A improve the ease of connecting the protrusions (protrusions 171A and 172A) of the tab components (power supply tab components 171 and 172) to the batteries 40 at positions facing the protrusions 171A and 172A. The insulating layer 176 may be formed, for example, from a sheet without openings. The insulating layer 176 may have the same configuration as the insulating layer 175. The insulating layers 173, 175, and 176 are formed, for example, from resin sheets. The insulating layers 173 , 175 , and 176 are attached to a resin sheet by, for example, heat fusion, and serve to fix the relative positional relationship between the power supply take-out tab parts 171 and 172 .

[0098] FIG. 37 shows an example cross-sectional configuration of the tab 170a of FIG. 36. For example, as shown in FIG. 37, the insulating layers 175 and 176 are formed to sandwich the portion of the power supply tab component 172 other than the protruding portion 172A (the portion corresponding to the overlapping portion 174). For example, as shown in FIG. 37, the insulating layers 173 and 176 are formed to sandwich the portion of the power supply tab component 171 other than the protruding portion 171A (the portion corresponding to the overlapping portion 174). In the tab 170a, the tops of the protruding portions 171A and 172A are located in the same plane. This allows the tab 170a to be integrally formed without impairing the electrical function of the tab 170a.

[0099] (Variation 2-4) In the second embodiment and variations 2-1, 2-2, and 2-3, the tab 170a may have power take-out tab parts 171 and 172 arranged on the same plane, as shown in Figures 38 and 39, and an insulating layer 94 may be provided between the end of the power take-out tab part 171 and the end of the power take-out tab part 172 (gap). The insulating layer 94 is made of, for example, a resin material. The insulating layer 94 is formed so as to connect the end of the power take-out tab part 171 and the end of the power take-out tab part 172 to each other.

[0100] Even in this case, when the housing 52 is torn open and the heat-absorbing agent 51 leaks out, the tabs 170a and 170b act as walls to keep the heat-absorbing agent 51 inside the battery unit 120. This prevents a decrease in the heat-absorbing effect of the heat-absorbing agent 51. Therefore, it is possible to provide a battery pack 2 having a structure that enhances the heat-absorbing effect of the heat-absorbing agent 51.

[0101] (Third embodiment) Next, a battery pack 3 according to a third embodiment of the present technology will be described. Fig. 40 illustrates an example of a perspective configuration of the battery pack 3. Fig. 41 illustrates an example of a perspective configuration of contents contained in the battery pack 3. Fig. 42 illustrates an example of an exploded perspective configuration of the battery pack 3.

[0102] 40 and 41, the battery pack 3 includes an exterior case 210, a battery unit 220 housed in the exterior case 210, and a control board 230. The control board 230 is connected to the positive and negative terminals of the battery unit 220, for example, and has circuits that measure the voltage of the battery and the battery unit, detect the remaining capacity of the battery unit, and measure the current output from the battery unit to detect the presence or absence of an overcurrent.

[0103] 42 , the exterior case 210 is composed of a lower case 210a and an upper case 210b. The lower case 210a and the upper case 210b are stacked together to form a storage space for accommodating the battery unit 220 and the control board 230. The exterior case 210 (e.g., the lower case 210a) is provided with external terminals 211 connected to the control board 230. The battery unit 220 is connected to the external terminals 211 via the control board 230.

[0104] The battery unit 220 has three batteries 40 and two tabs 270a, 270b. The three batteries 40 are arranged so that their axial directions face a common direction (e.g., the X direction in FIG. 42 ). The two tabs 270a, 270b are arranged opposite each other with the three batteries 40 in between. The tab 270a is arranged on one end of each battery 40, and the tab 270b is arranged on the other end of each battery 40. The three batteries 40 are electrically connected via the two tabs 270a, 270b. For example, the three batteries 40 are connected in series with each other via the two tabs 270a, 270b. The specific configuration of each tab 270a, 270b will be described in detail later.

[0105] The battery unit 220 further includes a heat absorption member 250 extending in the axial direction of the batteries 40, and a battery holder 260 that holds three batteries 40 in a tiered configuration. One heat absorption member 250 is disposed within the battery holder 260. One heat absorption member 250 is disposed in a triangular prism-shaped gap formed between three adjacent batteries 40. The heat absorption member 250 has a common configuration with the heat absorption member 50, except that its cross section is approximately triangular.

[0106] The battery holder 260 is composed of a pair of holders 260a and 260b, as shown in Figure 42. The holders 260a and 260b have a common structure. The holders 260a and 260b have the same structure as the holders 60a and 60b, except that they hold three batteries 40.

[0107] Each of the holders 260a and 260b has, for example, a side plate 61. The side plate 61 of the holder 260a and the side plate 61 of the holder 260b are arranged opposite each other with the plurality of batteries 40 between them in the extension direction of each battery 40 (the direction in which the positive terminals 41 and negative terminals 42, described below, face each other). In the holders 260a and 260b, the side plate 61 has openings 62 at locations facing the positive terminals 41 and negative terminals 42 of each battery 40. Therefore, the positive terminals 41 or negative terminals 42 are exposed in the openings 62. Furthermore, when the battery unit 220 is viewed in the axial direction of the batteries 40, the side plate 61 covers one end of one heat absorption member 250 and also covers one end of each battery 40 excluding at least a portion of the positive terminals 41 and negative terminals 42. Specifically, the side plate portion 61 covers the first end face 40a and the second end face 40b of each battery 40, excluding the positive electrode terminal 41 and the negative electrode terminal 42. Note that the positive electrode terminal 41 and the negative electrode terminal 42 may be partially covered by the side plate portion 61 as long as they can be electrically connected to the tabs 270a, 270b.

[0108] Each of the holders 260a and 260b has a support portion 63 that supports, for example, three batteries 40 in a tiered configuration with a predetermined gap between them. In this embodiment, "tiered" refers to a state in which one battery 40 is stacked on top of a group of two batteries 40 arranged side by side on a predetermined plane (XY plane). One side plate portion 61 is connected to each end of the support portion 63. The support portion 63 supports three cylindrical batteries 40 in a tiered configuration with a predetermined gap between them. An opening 64 is formed in the support portion 63 at a location surrounded by three adjacent cylindrical batteries 40. The location of the opening 64 in the support portion 63 (the location surrounded by three adjacent cylindrical batteries 40) serves as a storage portion 65 that stores a battery 40. There is one storage portion 65.

[0109] One heat absorption member 250 is disposed in one gap (accommodation section 65) surrounded by three adjacent batteries 40. One heat absorption member 250 contacts the outer peripheral surfaces of the three batteries 40 through openings 64. Openings 64 contact side plate portions 61 of holder 260a and side plate portions 61 of holder 260b, and one heat absorption member 250 contacts side plate portions 61 of holder 260a and side plate portions 61 of holder 260b through openings 64.

[0110] Next, the specific configuration of the tabs 270a and 270b will be described.

[0111] Fig. 44 shows an example of an exploded perspective configuration of the tab 270a. As shown in Fig. 44, the tab 270a is, for example, a tab module having an intermediate connection tab part 271 and a power supply take-out tab part 272. The intermediate connection tab part 271 and the power supply take-out tab part 272 are made of metal members.

[0112] The power supply extraction tab part 272 is connected to the positive electrode terminal 41 of one battery 40A (third battery) of the two batteries 40A belonging to the first group G3. The power supply extraction tab part 172 has a protrusion 272A that protrudes toward the battery 40. The protrusion 272A is located in a position facing the positive electrode terminal 41 of one battery 40A of the two batteries 40A belonging to the first group G3. The protrusion 272A is electrically connected to the corresponding positive electrode terminal 41 via a conductive material such as solder.

[0113] The intermediate connection tab part 271 is connected to the positive terminal 41 of the other battery 40A (fourth battery) of the two batteries 40A belonging to the first group G3 and the negative terminal 42 of a battery 40B (second battery) that does not belong to the first group G3. The intermediate connection tab part 271 has two protrusions 271A that protrude toward the battery 40. The two protrusions 271A are provided at a position facing the positive terminal 41 of the other battery 40A (fourth battery) of the two batteries 40A belonging to the first group G3 and at a position facing the negative terminal 42 of the battery 40B that does not belong to the first group G3. Of the two protrusions 271A, the protrusion 271A that is provided at a position facing the positive terminal 41 is electrically connected to the corresponding positive terminal 41 via a conductive material such as solder. Of the two protrusions 271A, the protrusion 271A provided at a position facing the negative electrode terminal 42 is electrically connected to the corresponding negative electrode terminal 42 via a conductive material such as solder.

[0114] The tab 270a further includes an insulating layer 273, as shown in FIG. 44 . The insulating layer 273 is disposed between the intermediate connection tab part 271 and the power take-out tab part 272, and is capable of insulating and isolating the intermediate connection tab part 271 and the power take-out tab part 272 from each other. The insulating layer 273 is formed, for example, of a resin sheet. The intermediate connection tab part 271, the power take-out tab part 272, and the insulating layer 273 are bonded together, for example, by heat fusion using the resin sheet that forms the insulating layer 273. Therefore, the insulating layer 273 serves to fix the relative positions of the intermediate connection tab part 271 and the power take-out tab part 272.

[0115] Figure 45(A) shows an example of the planar configuration of the intermediate connection tab part 271 and power extraction tab part 272 included in the tab 270a. Figure 45(B) shows an example of a configuration in which the planar configuration of the battery 40 and heat absorption member 250 is superimposed on the planar configuration of Figure 45(A). In the tab 270a, a portion of the intermediate connection tab part 271 and a portion of the power extraction tab part 272 overlap each other. In other words, the tab 270a has an overlapping portion 274 where the intermediate connection tab part 271 and the power extraction tab part 272 overlap each other. For example, as shown in Figure 45(B), the overlapping portion 274 is positioned opposite the heat absorption member 250 provided between the one battery 40 connected to the power extraction tab part 272 and the two batteries 40 connected to the intermediate connection tab part 271.

[0116] Fig. 46 shows an example of a cross-sectional configuration taken along line A-A in Fig. 45(A) . For example, as shown in Fig. 46 , the insulating layer 273 is formed so as to be sandwiched between the intermediate connection tab part 271 except for the protruding part 271A and the power supply tab part 272 except for the protruding part 272A.

[0117] Figure 47 shows an example of the developed perspective configuration of the tab 270b. The tab 270b is a tab (second tab) that connects to the terminals on the other ends of the three batteries 40. As shown in Figure 47, the tab 270b is, for example, a tab module having an intermediate connection tab part 281 and a power supply extraction tab part 282. The intermediate connection tab part 281 and the power supply extraction tab part 282 are made of metal.

[0118] The intermediate connection tab part 281 is electrically connected to the negative terminal 42 of one battery 40A (third battery) of the two batteries 40A belonging to the first group G3 and the positive terminal 41 of one battery 40B (second battery) that does not belong to the first group G3. The intermediate connection tab part 281 has two protrusions 281A that protrude toward the batteries 40. The two protrusions 281A are provided at a position facing the negative terminal 42 of one battery 40A (third battery) of the two batteries 40A belonging to the first group G3 and at a position facing the positive terminal 41 of the one battery 40B (second battery) that does not belong to the first group G3. Of the two protrusions 281A, the protrusion 281A that is provided at a position facing the negative terminal 42 is electrically connected to the corresponding negative terminal 42 via a conductive material such as solder. Of the two protrusions 281A, the protrusion 281A provided at a position facing the positive electrode terminal 41 is electrically connected to the corresponding positive electrode terminal 41 via a conductive material such as solder.

[0119] The power supply extraction tab part 282 is connected to the negative terminal 42 of one battery 40A (third battery) of the two batteries 40A belonging to the first group G3. The power supply extraction tab part 282 has a protrusion 282A that protrudes toward the battery 40. The protrusion 282A is located in a position facing the negative terminal 42 of one battery 40A (third battery) of the two batteries 40A belonging to the first group G3. The protrusion 282A is electrically connected to the corresponding negative terminal 42 via a conductive material such as solder.

[0120] The tab 270b further includes an insulating layer 283, as shown in FIG. 47 . The insulating layer 283 is disposed between the intermediate connection tab part 281 and the power take-out tab part 282, and is capable of insulating and isolating the intermediate connection tab part 281 and the power take-out tab part 282 from each other. The insulating layer 283 is formed, for example, of a resin sheet. The intermediate connection tab part 281, the power take-out tab part 282, and the insulating layer 283 are bonded together, for example, by heat fusion using the resin sheet that forms the insulating layer 283. Therefore, the insulating layer 283 serves to fix the relative positions of the intermediate connection tab part 281 and the power take-out tab part 282.

[0121] Figure 48(A) shows an example of the planar configuration of the intermediate connection tab part 281 and power extraction tab part 282 included in the tab 270b. Figure 48(B) shows an example of a configuration in which the planar configuration of the battery 40 and heat absorption member 250 is superimposed on the planar configuration of Figure 48(A). In the tab 270b, a portion of the intermediate connection tab part 281 and a portion of the power extraction tab part 282 overlap each other. In other words, the tab 270b has an overlapping portion 284 where the intermediate connection tab part 281 and the power extraction tab part 282 overlap each other. For example, as shown in Figure 48(B), the overlapping portion 284 is positioned opposite the heat absorption member 250 provided between the one battery 40 connected to the power extraction tab part 282 and the two batteries 40 connected to the intermediate connection tab part 281.

[0122] Fig. 49 shows an example of a cross-sectional configuration taken along line A-A in Fig. 48(A) . For example, as shown in Fig. 49 , the insulating layer 284 is disposed in the gap between the intermediate connection tab part 281 other than the protruding part 281A and the power supply tab part 282 other than the protruding part 282A.

[0123] 45A, for example, the power supply take-out tab part 272 of the tab 270a has a hook 272B. The hook 272B can be locked into the slit portion 31 of the control board 230 to fix the tab 270a to the control board 230.

[0124] Next, the effects of the battery pack 3 will be described.

[0125] In this embodiment, the tab 270a is formed to cover one end of the heat absorption member 250 when the battery unit 220 is viewed from the axial direction of the batteries 40. Furthermore, the tab 270b is formed to cover the other end of the heat absorption member 250 when the battery unit 220 is viewed from the axial direction of the batteries 40. As a result, when the housing 52 is torn open and the heat absorption agent 51 leaks out, the tabs 270a and 270b act as walls to keep the heat absorption agent 51 inside the battery unit 220. This makes it possible to prevent a decrease in the heat absorption effect of the heat absorption agent 51. Therefore, it is possible to provide a battery pack 3 having a structure that provides a high heat absorption effect of the heat absorption agent 51.

[0126] In this embodiment, when the battery unit 220 is viewed from the axial direction of the batteries 40, the tabs 270a are formed to cover one end of each heat absorption member 250 and one end of each battery 40. Furthermore, when the battery unit 220 is viewed from the axial direction of the batteries 40, the tabs 270b are formed to cover the other end of each heat absorption member 250 and the other end of each battery 40. As a result, when the housing 52 is torn open and the heat absorption agent 51 leaks out, the tabs 270a and 270b act as walls to keep the heat absorption agent 51 within the battery unit 220. This prevents a decrease in the heat absorption effect of the heat absorption agent 51. Therefore, a battery pack 3 having a structure that provides a high heat absorption effect due to the heat absorption agent 51 can be provided.

[0127] In this embodiment, when the battery unit 220 is viewed in the axial direction of the batteries 40, the side plate 61 of the holder 260a covers one end of the heat absorption member 250 and covers one end of each battery 40 except for at least a portion of the positive terminal 41 and the negative terminal 42. Furthermore, when the battery unit 220 is viewed in the axial direction of the batteries 40, the side plate 61 of the holder 260b covers the other end of the heat absorption member 250 and covers the other end of each battery 40 except for at least a portion of the positive terminal 41 and the negative terminal 42. This allows the side plate 61 to function as a wall to contain the heat absorption agent 51 within the battery unit 220 when the housing 52 is torn open and the heat absorption agent 51 leaks out. This prevents a decrease in the heat absorption effect of the heat absorption agent 51. Therefore, a battery pack 3 having a structure that enhances the heat absorption effect of the heat absorption agent 51 can be provided.

[0128] In this embodiment, the tab 270a is a tab module having an overlapping portion 274 where the power take-out tab part 272 and the intermediate connection tab part 271 overlap each other. Furthermore, the tab 270b is a tab module having an overlapping portion 284 where the power take-out tab part 282 and the intermediate connection tab part 281 overlap each other. The overlapping portion 274 is located in a position facing the heat absorption member 250 provided between the one battery 40 connected to the power take-out tab part 272 and the two batteries 40 connected to the intermediate connection tab part 271. The overlapping portion 284 is located in a position facing the heat absorption member 250 provided between the one battery 40 connected to the power take-out tab part 282 and the two batteries 40 connected to the intermediate connection tab part 281. As a result, when the housing 52 is torn open and the heat-absorbing agent 51 leaks out, the tabs 270a (specifically, the power takeout tab part 272 and the intermediate connection tab part 271) and the tabs 270b (specifically, the power takeout tab part 282 and the intermediate connection tab part 281) act as walls to keep the heat-absorbing agent 51 inside the battery unit 220. This makes it possible to prevent a decrease in the heat-absorbing effect of the heat-absorbing agent 51. Therefore, it is possible to provide a battery pack 3 having a structure in which the heat-absorbing agent 51 has a high heat-absorbing effect.

[0129] In this embodiment, an insulating layer 273 is provided to insulate and separate the power supply take-out tab part 272 and the intermediate connection tab part 271 from each other, and an insulating layer 283 is provided to insulate and separate the power supply take-out tab part 282 and the intermediate connection tab part 281 from each other. This allows the tab 270a to be integrally formed without impairing the electrical function of the tab 270a, and the tab 270b to be integrally formed without impairing the electrical function of the tab 270b.

[0130] In this embodiment, a hook 272B is provided on tab 270a, and a hook 282B is provided on tab 270b, which prevents tabs 270a and 270b from falling off battery unit 220 due to the force of gas ejection in the event of an abnormality, and allows leaked heat-absorbing agent 51 to be retained.

[0131] Next, a modified example of the battery pack 3 will be described.

[0132] (Variation 3-1) In the third embodiment, the tabs 270a (specifically, the power supply extraction tab part 272 and the intermediate connection tab part 271) may be formed to cover one end of the heat absorption member 250 when the battery unit 220 is viewed from the axial direction of the batteries 40, as shown in Figure 50, but may be formed to expose a portion of one end of each battery 40. Also, in the third embodiment, the tabs 270b (specifically, the power supply extraction tab part 282 and the intermediate connection tab part 281) may be formed to cover the other end of the heat absorption member 250 when the battery unit 220 is viewed from the axial direction of the batteries 40, as shown in Figure 51, but may be formed to expose a portion of the other end of each battery 40.

[0133] Even in this case, when the housing 52 is torn open and the heat-absorbing agent 51 leaks out, the tabs 270a and 270b act as walls to keep the heat-absorbing agent 51 inside the battery unit 220. This prevents a decrease in the heat-absorbing effect of the heat-absorbing agent 51. Therefore, it is possible to provide a battery pack 3 having a structure that enhances the heat-absorbing effect of the heat-absorbing agent 51.

[0134] (Variation 3-2) In the third embodiment and Variation 3-1, the tab 270a may further include insulating layers 275, 276, for example, as shown in FIG. 52 . The insulating layer 275 is disposed between the power supply extraction tab part 272 and the three batteries 40. The insulating layer 275 has three openings 275A at positions facing the two protrusions 271A and one protrusion 272A. The power supply extraction tab part 272 is electrically connected to the positive terminal 41 of the battery 40 facing the power supply extraction tab part 272 through the opening 275A of the insulating layer 275. The intermediate connection tab part 271 is electrically connected to the positive terminal 41 of one battery 40 and the negative terminal 42 of the other battery 40 through the two openings 275A of the insulating layer 275.

[0135] The insulating layer 276 is disposed between the intermediate connection tab component 271 and the inner wall of the exterior case 210. For example, as shown in FIG. 52 , the insulating layer 276 may have three openings 276A at positions facing two protrusions 271A and one protrusion 272A. The openings 276A improve the ease of connecting the protrusions (protrusions 271A, 272A) of the tab components (power supply tab component 271 and intermediate connection tab component 272) to the batteries 40 facing the protrusions 271A, 272A. The insulating layer 276 may be formed, for example, from a sheet without openings. The insulating layer 276 may have the same configuration as the insulating layer 275. The insulating layers 275, 276 are formed, for example, from resin sheets. The insulating layers 273, 275, and 276 are attached to a resin sheet by, for example, heat fusion, and serve to fix the relative positional relationship between the power supply tab part 272 and the intermediate connection tab part 271. This allows the tab 270a to be formed integrally without impairing the electrical function of the tab 270a.

[0136] In this modification, the tab 270b may further include insulating layers 285 and 286, as shown in FIG. 53 . The insulating layer 285 is disposed between the power supply extraction tab part 282 and the three batteries 40. The insulating layer 285 has three openings 285A at positions facing the two protrusions 281A and one protrusion 282A. The power supply extraction tab part 282 is electrically connected to the negative terminal 42 of the battery 40 facing the power supply extraction tab part 282 through the opening 285A of the insulating layer 285. The intermediate connection tab part 281 is electrically connected to the negative terminal 42 of one battery 40 and the positive terminal 41 of the other battery 40 facing the intermediate connection tab part 281 through the two openings 285A of the insulating layer 285.

[0137] The insulating layer 286 is disposed between the intermediate connection tab part 281 and the inner wall of the exterior case 210. For example, as shown in FIG. 53 , the insulating layer 286 may have three openings 286A at positions facing two protrusions 281A and one protrusion 282A. The openings 286A improve the ease of connecting the protrusions (protrusions 281A, 282A) of the tab parts (intermediate connection tab part 281 and power supply tab part 282) to the batteries 40 at positions facing the protrusions 281A, 282A. The insulating layer 286 may be formed, for example, from a sheet without openings. The insulating layer 286 may have the same configuration as the insulating layer 285. The insulating layers 285, 286 are formed, for example, from resin sheets. The insulating layers 283, 285, and 286 are attached to a resin sheet by, for example, heat fusion or the like, and serve to fix the relative positional relationship between the power supply take-out tab part 282 and the intermediate connection tab part 281. This allows the tab 270b to be formed integrally without impairing the electrical function of the tab 270b.

[0138] (Fourth embodiment) Next, a battery pack 4 according to a fourth embodiment of the present technology will be described. Fig. 54 illustrates an example of a perspective configuration of the battery pack 4. Fig. 55 illustrates an example of a perspective configuration of contents contained in the battery pack 4. Fig. 56 is a diagram illustrating an example of an exploded perspective configuration of the battery pack 4.

[0139] 54 and 55, the battery pack 4 includes an exterior case 310, a battery unit 320 housed in the exterior case 310, and a control board 330. The control board 330 is connected to the positive and negative terminals of the battery unit 320, for example, and has circuits that measure the voltage of the battery and the battery unit, detect the remaining capacity of the battery unit, and measure the current output from the battery unit to detect the presence or absence of an overcurrent.

[0140] 56 , the exterior case 310 is composed of a lower case 310a and an upper case 310b. By stacking the lower case 310a and the upper case 310b on top of each other, an accommodation space is formed to accommodate the battery unit 320 and the control board 330. The exterior case 310 (for example, the lower case 310a) is provided with external terminals 311 connected to the control board 330. The battery unit 320 is connected to the external terminals 311 via the control board 330.

[0141] The battery unit 320 includes multiple batteries 40 and two tabs 370a, 370b. The multiple batteries 40 are arranged so that their axial directions are aligned in a common direction (e.g., the X direction in FIG. 56 ). The two tabs 370a, 370b are arranged opposite each other with the multiple batteries 40 in between. The tab 370a is located at one end of each battery 40, and the tab 370b is located at the other end of each battery 40. The multiple batteries 40 are electrically connected via the two tabs 370a, 370b. For example, the multiple batteries 40 are connected in series with each other via the two tabs 370a, 370b. Note that the connection of the multiple batteries 40 is not limited to the above. The specific configuration of each tab 370a, 370b will be described in detail later. The battery unit 320 includes (2×n+1) batteries 40 (n is an integer greater than or equal to 2).

[0142] The battery unit 320 further includes a plurality of heat-absorbing members 350 extending in the axial direction of the batteries 40, and a battery holder 360 that holds (2×n+1) batteries 40 in layers. The plurality of heat-absorbing members 350 are arranged within the battery holder 360. The number of heat-absorbing members 350 is (2×n-1). The (2×n-1) heat-absorbing members 350 are arranged one by one in (2×n-1) triangular prism-shaped gaps formed by three adjacent batteries 40 among the (2×n+1) batteries 40. The heat-absorbing members 350 share a common configuration with the heat-absorbing member 50, except for the fact that their cross sections are approximately triangular.

[0143] The battery holder 360 is composed of a pair of holders 360a and 360b, as shown in Figure 56. The holders 360a and 360b have a common structure. The holders 360a and 360b have the same structure as the holders 60a and 60b, except that they hold (2 x n + 1) batteries 40.

[0144] Each of the holders 360a and 360b has, for example, a side plate 61. The side plate 61 of the holder 360a and the side plate 61 of the holder 360b are arranged opposite each other with the plurality of batteries 40 between them in the extension direction of each battery 40 (the direction in which the positive terminals 41 and negative terminals 42 face each other). In the holders 360a and 360b, the side plate 61 has openings 62 at locations facing the positive terminals 41 and negative terminals 42 of each battery 40. Therefore, the positive terminals 41 or negative terminals 42 are exposed in the openings 62. Furthermore, when the battery unit 320 is viewed in the axial direction of the batteries 40, the side plate 61 covers one end of each of the n heat absorption members 350 and also covers one end of each battery 40 excluding at least a portion of the positive terminals 41 and negative terminals 42. Specifically, the side plate portion 61 covers the first end face 40a and the second end face 40b of each battery 40, excluding the positive electrode terminal 41 and the negative electrode terminal 42. Note that the positive electrode terminal 41 and the negative electrode terminal 42 may be partially covered by the side plate portion 61 as long as they can be electrically connected to the tabs 370a, 370b.

[0145] Each of the holders 360a and 360b has a support portion 63 that supports, for example, (2×n+1) batteries 40 in a tiered arrangement with a predetermined gap between them. In this embodiment, "tiered arrangement" refers to a state in which an assembly of n batteries 40 arranged side by side on a predetermined plane (XY plane) is stacked on top of an assembly of n+1 batteries 40 arranged side by side on a predetermined plane (XY plane). Side plates 61 are connected to both ends of the support portion 63, one at a time. The support portion 63 supports (2×n+1) cylindrical batteries 40 in a tiered arrangement with a predetermined gap between them. An opening 64 is formed in the support portion 63 at a location surrounded by three adjacent cylindrical batteries 40. The location where the opening 64 is formed in the support portion 63 (the location surrounded by three adjacent cylindrical batteries 40) serves as a storage portion 65 that stores a battery 40. The number of storage portions 65 is n.

[0146] The (2×n−1) heat absorption members 350 are arranged one by one in gaps (accommodating sections 65) at (2×n−1) locations surrounded by three adjacent batteries 40 among the (2×n+1) batteries 40. Each heat absorption member 350 contacts the outer periphery of the three batteries 40 via an opening 64. The openings 64 contact the side plate sections 61 of holder 360a and holder 360b, and the heat absorption members 350 contact the side plate sections 61 of holder 360a and holder 360b via the openings 64.

[0147] FIG. 57 shows an example of the arrangement of (2×n+1) batteries 40 held in a battery holder 360 when n = 3. Of the (2×n+1) batteries 40 held in the battery holder 360, 2×n batteries 40 belong to one of n groups (first group G3, second group G4, third group G5). The first group G3, second group G4, and third group G5 are conceptually used to classify the 2×n batteries 40 according to their locations. Of the (2×n+1) batteries 40, two batteries 40 (first batteries) belong to each of the first group G3 to third group G5, and one battery 40B (second battery) does not belong to any of the first group G3 to third group G5.

[0148] The two batteries 40A belonging to the first group G3 are held by the battery holder 360 so that the positive terminals 41 are on the tab 370a side in the axial direction of the batteries 40. In each of the second group G4 to the third group G5, one battery 40 is held by the battery holder 360 so that the positive terminal 41 is on the tab 370a side in the axial direction of the batteries 40, and the other battery 40 is held by the battery holder 360 so that the positive terminal 41 is on the tab 370b side in the axial direction of the battery 40. In each layer of the multiple batteries 40 arranged in layers within the battery holder 360, the batteries 40 of each group are arranged one by one in order in a first direction (Y direction in FIG. 57 ) that is perpendicular to the axial direction of the batteries 40 (X direction in FIG. 57 ).

[0149] In the second group G4, one battery 40C is held by the battery holder 360 so that its positive terminal 41 faces the tab 370a in the axial direction of the battery 40, and the other battery 40C is held by the battery holder 360 so that its positive terminal 41 faces the tab 370b in the axial direction of the battery 40. In the third group G5, one battery 40D is held by the battery holder 360 so that its positive terminal 41 faces the tab 370a in the axial direction of the battery 40, and the other battery 40D is held by the battery holder 360 so that its positive terminal 41 faces the tab 370b in the axial direction of the battery 40. A single battery 40B that does not belong to any of the first to third groups G3 to G5 is held by the battery holder 360 so that its positive terminal 41 faces the tab 370b in the axial direction of the battery 40.

[0150] The batteries 40A belonging to the first group G3 are arranged in a region R3 that extends across each tier of the batteries 40 arranged in a tiered configuration within the battery holder 360. The batteries 40C belonging to the second group G4 are arranged in a region R4 that extends across each tier of the batteries 40 arranged in a tiered configuration within the battery holder 360. The batteries 40D belonging to the third group G5 are arranged in a region R5 that extends across each tier of the batteries 40 arranged in a tiered configuration within the battery holder 360. The regions R3, R4, and R5 extend in a direction that intersects obliquely (e.g., at 45 degrees) with the normal to a predetermined plane (the XY plane). In each tier of the batteries 40 arranged in a tiered configuration within the battery holder 360, the batteries 40A, 40C, and 40D are arranged one by one in order in a first direction (the Y direction in FIG. 57 ) that is perpendicular to the axial direction of the batteries 40 (the X direction in FIG. 57 ).

[0151] Next, the specific configuration of the tabs 370a and 370b will be described.

[0152] 58 shows an example of an exploded perspective configuration of the tab 370a when n = 3. The tab 370a is a tab module having n intermediate connection tab parts (intermediate connection tab parts 371, 372, 373) and one power supply take-out tab part 374. The n intermediate connection tab parts (intermediate connection tab parts 371, 372, 373) and one power supply take-out tab part 374 are made of metal members.

[0153] The n-1 intermediate connection tab parts (intermediate connection tab parts 372, 373) are connected to the negative terminal 42 of the battery 40 belonging to the kth group (k = 2 to n) and the positive terminal 41 of the battery 40 belonging to the k-1th group. The remaining intermediate connection tab part (intermediate connection tab part 371) is connected to the positive terminal 41 of one of the two batteries 40A belonging to the first group G3 and the negative terminal 42 of a battery 40B that does not belong to any of the first to nth groups.

[0154] The intermediate connection tab part 372 is connected to the negative terminal 42 of the battery 40C belonging to the second group G4 and the positive terminal 41 of the battery 40A belonging to the first group. The intermediate connection tab part 373 is connected to the negative terminal 42 of the battery 40D belonging to the third group G5 and the positive terminal 41 of the battery 40A belonging to the second group. The intermediate connection tab part 371 is connected to the positive terminal 41 of the battery 40A not connected to the intermediate connection tab part 372, of the two batteries 40A belonging to the first group G3, and to the negative terminal 42 of the battery 40B that does not belong to any of the first to third groups G3 to G5.

[0155] The tab 370a further includes insulating layers 375, 376, and 377, as shown in FIG. 58 . The insulating layer 375 is disposed between the intermediate connection tab parts 371 and 372, and can insulate and separate the intermediate connection tab parts 371 and 372 from each other. The insulating layer 376 is disposed between the intermediate connection tab parts 372 and 373, and can insulate and separate the intermediate connection tab parts 372 and 373 from each other. The insulating layer 377 is disposed between the intermediate connection tab part 373 and power supply takeoff tab part 374, and can insulate and separate the intermediate connection tab parts 373 and 374 from each other.

[0156] The insulating layers 375, 376, 377 are made of, for example, resin sheets. The intermediate connection tab parts 371, 372, 373, the power supply take-out tab part 374, and the insulating layers 375, 376, 377 are bonded together by, for example, heat fusion using the resin sheets that make up the insulating layers 375, 376, 377. Therefore, the insulating layers 375, 376, 377 serve to fix the relative positional relationship between the intermediate connection tab parts 371, 372, 373 and the power supply take-out tab part 374.

[0157] Figure 59 shows an example of the planar configuration of the intermediate connection tab parts 371, 372, and 373 and the power supply tab part 374 included in the tab 370a. Figure 60 shows an example of a configuration in which the planar configuration of the batteries 40 and the heat absorption member 350 are superimposed on the planar configuration of Figure 59. In the tab 370a, a portion of the intermediate connection tab part 371 and a portion of the intermediate connection tab part 372 overlap each other. That is, the tab 370a has an overlapping portion 378a where the intermediate connection tab parts 371 and 372 overlap each other. For example, as shown in Figure 60, the overlapping portion 378a is positioned opposite the heat absorption member 350 provided between the two batteries 40 connected to the intermediate connection tab part 371 and the one battery 40 connected to the intermediate connection tab part 372.

[0158] In the tab 370a, a portion of the intermediate connection tab part 372 and a portion of the intermediate connection tab part 373 overlap each other. That is, the tab 370a has an overlapping portion 378b where the intermediate connection tab part 372 and the intermediate connection tab part 373 overlap each other. The overlapping portion 378b is located in a position facing the heat absorption member 350 provided between the two batteries 40 connected to the intermediate connection tab part 372 and the one battery 40 connected to the intermediate connection tab part 373, as shown in FIG. 60 , for example.

[0159] In the tab 370a, a portion of the intermediate connection tab part 373 and a portion of the power supply take-out tab part 374 overlap each other. That is, the tab 370a has an overlapping portion 378c where the intermediate connection tab part 373 and the power supply take-out tab part 374 overlap each other. For example, as shown in FIG. 60 , the overlapping portion 378c is located in a position facing the heat absorption member 350 provided between the two batteries 40 connected to the intermediate connection tab part 373 and the one battery 40 connected to the power supply take-out tab part 374.

[0160] Fig. 61 shows an example of a cross-sectional configuration taken along line A-A in Fig. 59. For example, as shown in Fig. 61, the insulating layer 375 is formed so as to be sandwiched between the intermediate connection tab part 373 except for the protrusion 373A and the power supply tab part 374 except for the protrusion 374A. For example, as shown in Fig. 61, the insulating layer 376 is formed so as to be sandwiched between the intermediate connection tab part 372 except for the protrusion 372A and the intermediate connection tab part 373 except for the protrusion 373A. For example, as shown in Fig. 61, the insulating layer 377 is formed so as to be sandwiched between the intermediate connection tab part 371 except for the protrusion 371A and the intermediate connection tab part 372 except for the protrusion 372A.

[0161] 62 shows an example of an exploded perspective configuration of the tab 370b when n = 3. The tab 370b is a tab module having n intermediate connection tab parts (intermediate connection tab parts 381, 382, ​​383) and one power supply take-out tab part 384. The n intermediate connection tab parts (intermediate connection tab parts 381, 382, ​​383) and one power supply take-out tab part 384 are made of metal members.

[0162] The power supply extraction tab part 384 is connected to the negative terminal 42 of one battery 40A belonging to the first group G3. The n-1 intermediate connection tab parts (intermediate connection tab parts 381, 382) are connected to the negative terminal 42 of one battery 40 belonging to the kth group (k = 2 to n) and the positive terminal 41 of the other battery 40 belonging to the kth group. The remaining intermediate connection tab part (intermediate connection tab part 383) is connected to the positive terminal 41 of the other battery 40A (the battery 40A not connected to the power supply extraction tab part 384) of the two batteries 40A belonging to the first group G3 and the positive terminal 41 of a battery 40B that does not belong to any of the first to nth groups.

[0163] Of the two batteries 40D belonging to the third group G5, the intermediate connection tab part 381 is connected to the negative terminal 42 of one battery 40D and the positive terminal 41 of the other battery 40D. Of the two batteries 40C belonging to the second group G4, the intermediate connection tab part 382 is connected to the negative terminal 42 of one battery 40C and the positive terminal 41 of the other battery 40C. Of the two batteries 40C belonging to the first group G3, the intermediate connection tab part 383 is connected to the negative terminal 42 of the other battery 40C (the battery 40C not connected to the power extraction tab part 384) and the positive terminal 41 of a battery 40B that does not belong to any of the first to nth groups.

[0164] The tab 370b further includes insulating layers 385, 386, 387, and 388, as shown in FIG. 62 . The insulating layer 385 is disposed between the intermediate connection tab parts 381 and 382, ​​and can insulate the intermediate connection tab parts 381 and 382 from each other. The insulating layer 386 is disposed between the intermediate connection tab parts 382 and 383, and can insulate the intermediate connection tab parts 382 and 383 from each other. The insulating layer 387 is disposed between the intermediate connection tab parts 382 and 384, and can insulate the intermediate connection tab parts 382 and 384 from each other. The insulating layer 388 is disposed between the intermediate connection tab parts 383 and 384, and can insulate the intermediate connection tab parts 383 and 384 from each other.

[0165] The insulating layers 385, 386, 387, and 388 are made of, for example, resin sheets. The intermediate connection tab parts 381, 382, ​​and 383, the power supply take-out tab part 384, and the insulating layers 385, 386, 387, and 388 are bonded together by, for example, heat fusion using the resin sheets that make up the insulating layers 385, 386, 387, and 388. Therefore, the insulating layers 385, 386, 387, and 388 serve to fix the relative positional relationship between the intermediate connection tab parts 381, 382, ​​and 383 and the power supply take-out tab part 384.

[0166] Figure 63 shows an example of the planar configuration of the intermediate connection tab parts 381, 382, ​​and 383 and the power supply tab part 384 included in the tab 370b. Figure 64 shows an example of a configuration in which the planar configuration of the batteries 40 and the heat absorption member 350 are superimposed on the planar configuration of Figure 63. In the tab 370b, a portion of the intermediate connection tab part 381 and a portion of the intermediate connection tab part 382 overlap each other. That is, the tab 370b has an overlapping portion 388a where the intermediate connection tab parts 381 and 382 overlap each other. For example, as shown in Figure 64, the overlapping portion 388a is positioned opposite the heat absorption member 350 provided between the two batteries 40 connected to the intermediate connection tab part 381 and the one battery 40 connected to the intermediate connection tab part 382.

[0167] In the tab 370b, a portion of the intermediate connection tab part 382 and a portion of the intermediate connection tab part 383 overlap each other. That is, the tab 370b has an overlapping portion 388b where the intermediate connection tab part 382 and the intermediate connection tab part 383 overlap each other. For example, as shown in FIG. 64 , the overlapping portion 388b is located in a position facing the heat absorption member 350 provided between the two batteries 40 connected to the intermediate connection tab part 382 and the one battery 40 connected to the intermediate connection tab part 383.

[0168] In the tab 370b, a portion of the intermediate connection tab part 382 and a portion of the power supply take-out tab part 384 overlap each other. That is, the tab 370b has an overlapping portion 388c where the intermediate connection tab part 382 and the power supply take-out tab part 384 overlap each other. The overlapping portion 388c is located in a position facing the heat absorption member 350 provided between one battery 40 connected to the intermediate connection tab part 382, ​​one battery 40 connected to the intermediate connection tab part 383, and one battery 40 connected to the power supply take-out tab part 384, as shown in FIG. 64 , for example.

[0169] In the tab 370b, a portion of the intermediate connection tab part 383 and a portion of the power supply take-out tab part 384 overlap each other. That is, the tab 370b has an overlapping portion 388d where the intermediate connection tab part 383 and the power supply take-out tab part 384 overlap each other. For example, as shown in FIG. 64 , the overlapping portion 388d is located in a position facing the heat absorption member 350 provided between the two batteries 40 connected to the intermediate connection tab part 383 and the one battery 40 connected to the power supply take-out tab part 384.

[0170] Fig. 65 shows an example of a cross-sectional configuration taken along line A-A in Fig. 63. For example, as shown in Fig. 65, the insulating layer 385 is formed so as to be sandwiched between the intermediate connection tab part 382 except for the protruding portion 382A and the intermediate connection tab part 383 except for the protruding portion 383A. For example, as shown in Fig. 65, the insulating layer 386 is formed so as to be sandwiched between the intermediate connection tab part 381 except for the protruding portion 381A and the intermediate connection tab part 382 except for the protruding portion 382A. For example, as shown in Fig. 65, the insulating layer 388 is formed so as to be sandwiched between the intermediate connection tab part 383 except for the protruding portion 383A and the power supply tab part 384 except for the protruding portion 384A. The insulating layer 387 is formed so as to be sandwiched between the intermediate connection tab part 382 and the power supply tab part 384, except for the protrusion 382A.

[0171] Next, the effects of the battery pack 4 will be described.

[0172] In this embodiment, the tab 370a is formed to cover one end of the heat absorption member 350 when the battery unit 320 is viewed from the axial direction of the batteries 40. Furthermore, the tab 370b is formed to cover the other end of the heat absorption member 350 when the battery unit 320 is viewed from the axial direction of the batteries 40. As a result, when the housing 52 is torn open and the heat absorption agent 51 leaks out, the tabs 370a and 370b act as walls to keep the heat absorption agent 51 within the battery unit 320. This makes it possible to prevent a decrease in the heat absorption effect of the heat absorption agent 51. Therefore, it is possible to provide a battery pack 4 having a structure that provides a high heat absorption effect of the heat absorption agent 51.

[0173] In this embodiment, when the battery unit 320 is viewed from the axial direction of the batteries 40, the tabs 370a are formed to cover one end of each heat absorption member 350 and one end of each battery 40. Furthermore, when the battery unit 320 is viewed from the axial direction of the batteries 40, the tabs 370b are formed to cover the other end of each heat absorption member 350 and the other end of each battery 40. As a result, when the housing 52 is torn open and the heat absorption agent 51 leaks out, the tabs 370a and 370b act as walls to contain the heat absorption agent 51 within the battery unit 320. This prevents a decrease in the heat absorption effect of the heat absorption agent 51. Therefore, a battery pack 4 having a structure that provides a high heat absorption effect due to the heat absorption agent 51 can be provided.

[0174] In this embodiment, when the battery unit 320 is viewed in the axial direction of the batteries 40, the side plate 61 of the holder 360a covers one end of the heat absorption member 350 and covers one end of each battery 40 except for at least a portion of the positive terminal 41 and the negative terminal 42. Furthermore, when the battery unit 320 is viewed in the axial direction of the batteries 40, the side plate 61 of the holder 360b covers the other end of the heat absorption member 350 and covers the other end of each battery 40 except for at least a portion of the positive terminal 41 and the negative terminal 42. This allows the side plate 61 to function as a wall to contain the heat absorption agent 51 within the battery unit 320 when the housing 52 is torn open and the heat absorption agent 51 leaks out. This prevents a decrease in the heat absorption effect of the heat absorption agent 51. Therefore, a battery pack 4 having a structure that provides a high heat absorption effect due to the heat absorption agent 51 can be provided.

[0175] In this embodiment, the tab 370a is a tab module having an overlapping portion 378a where the intermediate connection tab parts 371 and 372 overlap each other, an overlapping portion 378b where the intermediate connection tab parts 372 and 373 overlap each other, and an overlapping portion 378c where the intermediate connection tab part 373 and power take-off tab part 374 overlap each other. Furthermore, the tab 370b is a tab module having an overlapping portion 388a where the intermediate connection tab parts 381 and 382 overlap each other, an overlapping portion 388b where the intermediate connection tab parts 382 and 383 overlap each other, an overlapping portion 388c where the intermediate connection tab parts 382 and 384 overlap each other, and an overlapping portion 388d where the intermediate connection tab parts 383 and 384 overlap each other.

[0176] The overlap portion 378a is positioned opposite the heat absorption member 350 provided between the two batteries 40 connected to the intermediate connection tab part 371 and the one battery 40 connected to the intermediate connection tab part 372. The overlap portion 378b is positioned opposite the heat absorption member 350 provided between the two batteries 40 connected to the intermediate connection tab part 372 and the one battery 40 connected to the intermediate connection tab part 373. The overlap portion 378c is positioned opposite the heat absorption member 350 provided between the two batteries 40 connected to the intermediate connection tab part 373 and the one battery 40 connected to the power removal tab part 374. As a result, when the housing 52 is torn open and the heat-absorbing agent 51 leaks out, the tab 370a (specifically, the intermediate connection tab parts 371 to 373 and the power supply take-out tab part 374) and the tab 370b (specifically, the intermediate connection tab parts 381 to 383 and the power supply take-out tab part 384) act as walls to keep the heat-absorbing agent 51 inside the battery unit 320. This makes it possible to prevent a decrease in the heat-absorbing effect of the heat-absorbing agent 51. Therefore, it is possible to provide a battery pack 4 having a structure that provides a high heat-absorbing effect of the heat-absorbing agent 51.

[0177] In this embodiment, there are provided an insulating layer 375 that insulates and separates the intermediate connection tab parts 371 and 372 from each other, an insulating layer 376 that insulates and separates the intermediate connection tab parts 372 and 373 from each other, and an insulating layer 377 that insulates and separates the intermediate connection tab parts 373 and 374 from each other. Furthermore, in this embodiment, there are provided an insulating layer 385 that insulates and separates the intermediate connection tab parts 381 and 382 from each other, an insulating layer 386 that insulates and separates the intermediate connection tab parts 382 and 383 from each other, an insulating layer 387 that insulates and separates the intermediate connection tab parts 382 and 384 from each other, and an insulating layer 388 that insulates and separates the intermediate connection tab parts 383 and 384 from each other. This allows the tab 370a to be integrally formed without impairing the electrical function of the tab 370a, and allows the tab 370b to be integrally formed without impairing the electrical function of the tab 370b.

[0178] In this embodiment, a hook 374B is provided on tab 370a, and a hook 384B is provided on tab 370b, which prevents tabs 370a and 370b from falling off battery unit 320 due to the force of gas ejection in the event of an abnormality, and allows leaked heat-absorbing agent 51 to be retained.

[0179] Next, a modified example of the battery pack 4 will be described.

[0180] (Variation 4-1) In the fourth embodiment, as shown in Figure 66, when the battery unit 320 is viewed from the axial direction of the batteries 40, the tab 370a may be formed to cover one end of the heat absorption member 350, but may be formed to expose a portion of one end of each battery 40. Also, in the fourth embodiment, as shown in Figure 67, when the battery unit 320 is viewed from the axial direction of the batteries 40, the tab 370b may be formed to cover the other end of the heat absorption member 350, but may be formed to expose a portion of the other end of each battery 40.

[0181] Even in this case, when the housing 52 is torn open and the heat-absorbing agent 51 leaks out, the tabs 370a and 370b act as walls to keep the heat-absorbing agent 51 inside the battery unit 320. This prevents a decrease in the heat-absorbing effect of the heat-absorbing agent 51. Therefore, it is possible to provide a battery pack 4 having a structure that provides a high heat-absorbing effect of the heat-absorbing agent 51.

[0182] (Variation 4-2) In the fourth embodiment and Variation 4-1, the tab 370a may further include insulating layers 378, 379, for example, as shown in FIG. 68 . The insulating layer 378 is disposed between the power extraction tab part 374 and the plurality of batteries 40. The insulating layer 378 has a plurality of (seven) openings 378A at positions facing two protrusions 371A, two protrusions 372A, two protrusions 373A, and one protrusion 374A. The intermediate connection tab parts 371 to 373 and the power extraction tab part 374 are electrically connected to the plurality of (seven) batteries 40 via the a plurality of (seven) openings 375A in the insulating layer 378.

[0183] The insulating layer 379 is disposed between the interconnection tab component 371 and the inner wall of the exterior case 310. For example, as shown in FIG. 68 , the insulating layer 379 may have multiple (seven) openings 379A at positions facing two protrusions 371A, two protrusions 372A, two protrusions 373A, and one protrusion 374A. The openings 379A improve the ease of connecting the protrusions (protrusions 371A, 372A, 373A, 374A) of the tab components (power supply tab component 374 and intermediate connection tab components 371, 372, 373) to the batteries 40 facing the protrusions 371A, 372A, 373A, 374A. The insulating layer 379 may be formed, for example, from a sheet without openings. The insulating layer 379 may have the same configuration as the insulating layer 378. The insulating layers 378 and 379 are made of, for example, a resin sheet. The insulating layers 375 to 379 are attached to the resin sheet by, for example, heat fusion or the like, and serve to fix the relative positional relationship between the intermediate connection tab parts 371 to 373 and the power supply tab part 374.

[0184] Furthermore, in this modification, the tab 370b may further include insulating layers 389a, 389b, for example, as shown in FIG. 69 . The insulating layer 389a is disposed between the power extraction tab part 384 and the plurality of batteries 40. The insulating layer 389a has a plurality of (seven) openings 389a1 at positions facing the two protrusions 381A, two protrusions 382A, two protrusions 383A, and one protrusion 384A. The intermediate connection tab parts 381-383 and the power extraction tab part 384 are electrically connected to the plurality of (seven) batteries 40 via the a plurality of (seven) openings 389a1 of the insulating layer 389a.

[0185] The insulating layer 389b is disposed between the intermediate connection tab component 381 and the inner wall of the exterior case 310. For example, as shown in FIG. 69 , the insulating layer 389b may have multiple (seven) openings 389b1 at positions facing two protrusions 381A, two protrusions 382A, two protrusions 383A, and one protrusion 384A. The openings 389b1 improve the ease of connecting the protrusions (protrusions 381A, 382A, 383A, 384A) of the tab components (power supply tab component 384 and intermediate connection tab components 381, 382, ​​383) to the batteries 40 facing the protrusions 381A, 382A, 383A, 384A. The insulating layer 389b may be formed, for example, from a sheet without openings. The insulating layer 389b may have the same configuration as the insulating layer 389a. The insulating layers 389a, 389b are made of, for example, a resin sheet. The insulating layers 385-388, 389a, 389b are attached to the resin sheet by, for example, heat fusion or the like, and serve to fix the relative positional relationship between the intermediate connection tab parts 381-383 and the power supply tab part 384. This allows the tabs 370a, 370b to be formed integrally without impairing the electrical functions of the tabs 370a, 370b.

[0186] Although the present technology has been described above with reference to one embodiment, the present technology is not limited to the aspect described in the above embodiment, and various modifications are possible with respect to the present technology.

[0187] In the first embodiment, the plurality of batteries 40 in the battery unit 20 may be stacked in three layers, for example, as shown in Fig. 70. Also, in the fourth embodiment, the plurality of batteries 40 in the battery unit 320 may be stacked in three layers, for example, as shown in Figs. 71, 72, 73, and 74. In this case, the number of batteries 40 included in each layer may be the same, for example, as shown in Figs. 71, 72, and 74. Also, for example, as shown in Fig. 73, the number of batteries 40 included in a specific layer may be different from the number of batteries 40 included in other layers.

[0188] Furthermore, in the second embodiment, the battery unit 120 may have a plurality of batteries 40. In this case, the plurality of batteries 40 may be arranged side by side on a predetermined plane (XY plane). Alternatively, the plurality of batteries 40 may be arranged side by side in a predetermined plane (XZ plane), for example, as shown in FIG. 75. In this case, each heat absorption member 150 is arranged between two batteries 40 adjacent in the Z direction, for example, as shown in FIG. 75.

[0189] In the first and fourth embodiments, the number of layers of the plurality of batteries 40 in the battery unit 20, 320 is not limited to two, but may be three or more.

[0190] Although the battery structure of the secondary battery has been described as cylindrical, the battery structure of the secondary battery applied to the battery pack of the present technology is not particularly limited. Specifically, the battery structure of the secondary battery may be prismatic or coin-shaped.

[0191] The structure of the secondary battery is not particularly limited. Specifically, the secondary battery may have a structure other than a wound structure, such as a laminated structure.

[0192] Although lithium is used as the electrode reactant for the secondary battery, the type of the electrode reactant is not particularly limited. Specifically, the electrode reactant may be other Group 1 elements in the long periodic table, such as sodium and potassium, or Group 2 elements in the long periodic table, such as magnesium and calcium, or other light metals, such as aluminum.

[0193] The effects described in this specification are merely examples, and the effects of the present technology are not limited to the effects described in this specification. Therefore, other effects may be obtained with respect to the present technology.

[0194] The present technology may also be configured as follows: <1> A battery pack including a battery unit having: a plurality of batteries; one or more heat-absorbing members each having a heat-absorbing agent and a container for accommodating the heat-absorbing agent, the one or more heat-absorbing members extending in an axial direction of the batteries and arranged adjacent to at least two of the batteries; a battery holder for holding the plurality of batteries; a first tab connected to terminals on one ends of the plurality of batteries; and a second tab connected to terminals on the other ends of the plurality of batteries, wherein the first tab is formed to cover one end of the one or more heat-absorbing members when the battery unit is viewed in the axial direction of the batteries, and the second tab is formed to cover the other end of the one or more heat-absorbing members when the battery unit is viewed in the axial direction of the batteries. <2> The battery pack according to <1>, wherein the number of batteries is two, and the number of heat-absorbing members is one, and the heat-absorbing member is arranged adjacent to the two batteries. <3> The battery pack according to <2>, wherein the batteries have a positive terminal at one end and a negative terminal at the other end, the two batteries are held by the battery holder so that the positive terminals face opposite each other in the axial direction of the batteries, the first tab is a tab module having a first tab part connected to the positive terminal of one of the batteries and a second tab part connected to the negative terminal of the other battery, and the second tab is a tab module having an intermediate connection tab part connected to the negative terminal of one of the batteries and the positive terminal of the other battery. <4> The battery pack according to <3>, wherein the first tab has an overlapping portion where the first tab part and the second tab part overlap each other. <5> The battery pack according to <4>, wherein the overlapping portion is positioned opposite one end of the heat absorption member. <6> The battery pack according to <4>, wherein the overlap portion is not disposed at a position facing one end of the heat absorption member, but is disposed only at a position not facing one end of the heat absorption member. <7> The battery pack according to <5> or <6>, wherein the first tab has an insulating layer that insulates and separates the first tab part and the second tab part from each other. <8> The battery pack according to <5> or <6>, wherein 2×n batteries (n is an integer of 2 or more),a battery unit having a heat-absorbing agent and a container for accommodating the heat-absorbing agent, and n-1 heat-absorbing members extending in an axial direction of the battery; a battery holder for holding the 2×n batteries in layers; first tabs connected to terminals on one ends of the 2×n batteries; and second tabs connected to terminals on the other ends of the 2×n batteries, wherein the n-1 heat-absorbing members are arranged one by one in n-1 gaps formed by four adjacent batteries in the 2×n batteries, the first tabs are formed to cover one end of each of the heat-absorbing members when the battery unit is viewed in the axial direction of the battery, and the second tabs are formed to cover the other end of each of the heat-absorbing members when the battery unit is viewed in the axial direction of the battery. <9> The battery has a positive terminal at one end and a negative terminal at the other end, n is an integer equal to or greater than 4, and among the 2×n batteries, n first batteries belonging to a first group are held by the battery holder so that the positive terminals are on the first tab side in the axial direction of the batteries, and among the 2×n batteries, n second batteries belonging to a second group are held by the battery holder so that the positive terminals are on the second tab side in the axial direction of the batteries, and the first tabs include: a first tab part connected to the positive terminals of a plurality of third batteries that are part of the n first batteries that belong to the first group; and a second tab part connected to the negative terminals of a plurality of fourth batteries that are part of the n second batteries that belong to the second group. a tab module including: a first intermediate connection tab part connected to the positive terminals of a plurality of fifth batteries other than the plurality of third batteries among the n first batteries belonging to the first group, and to the negative terminals of a plurality of sixth batteries other than the plurality of fourth batteries among the n second batteries belonging to the second group, wherein the second tab is a tab module including: a second intermediate connection tab part connected to the negative terminals of the plurality of third batteries and the positive terminals of the plurality of fifth batteries; and a third intermediate connection tab part connected to the positive terminals of the plurality of fourth batteries and the negative terminals of the plurality of sixth batteries.The battery pack according to <8>. <10> The battery pack according to <9>, wherein the first tab has a first overlapping portion where the first tab part and the first intermediate connection tab part overlap each other, and a second overlapping portion where the second tab part and the first intermediate connection tab part overlap each other, and the second tab has a third overlapping portion where the second intermediate connection tab part and the third intermediate connection tab part overlap each other. <11> The battery pack according to <10>, wherein the first overlap portion is disposed at a position facing one end of the heat absorption member disposed between the plurality of third batteries connected to the first tab part and the plurality of sixth batteries connected to the first intermediate connection tab part; the second overlap portion is disposed at a position facing one end of the heat absorption member disposed between the plurality of fourth batteries connected to the second tab part and the plurality of fifth batteries connected to the first intermediate connection tab part; and the third overlap portion is disposed at a position facing the other end of the heat absorption member disposed between the plurality of fifth batteries connected to the second intermediate connection tab part and the plurality of sixth batteries connected to the third intermediate connection tab part. <12> The battery pack according to <10>, wherein the first overlap portion and the second overlap portion are not positioned opposite one end of each of the heat absorption members, but are positioned opposite one end of each of the heat absorption members, and the third overlap portion is not positioned opposite the other end of each of the heat absorption members, but is positioned opposite the other end of each of the heat absorption members. <13> The battery pack according to <11> or <12>, wherein the first tab has a first insulating layer that insulates and separates the first tab part and the second tab part from the first intermediate connection tab part, and the second tab has a second insulating layer that insulates and separates the second intermediate connection tab part from the third intermediate connection tab part. <14> (2×n+1) batteries (n is an integer of 1 or more); (2×n-1) heat-absorbing members each having a heat-absorbing agent and a container for accommodating the heat-absorbing agent, and extending in the axial direction of the batteries; and a battery holder for holding the (2×n+1) batteries in a tiered configuration.The battery pack according to <1>, comprising: a battery unit having first tabs connected to terminals on one ends of the (2×n+1) batteries; and second tabs connected to terminals on the other ends of the (2×n+1) batteries, wherein the (2×n-1) heat absorption members are arranged one at a time in n gaps formed by three adjacent batteries in the (2×n+1) batteries, the first tabs are formed to cover one end of each of the heat absorption members when the battery unit is viewed from the axial direction of the batteries, and the second tabs are formed to cover the other end of each of the heat absorption members when the battery unit is viewed from the axial direction of the batteries. <15> The battery has a positive terminal at one end and a negative terminal at the other end, n is 1, two first batteries of the three batteries belonging to a first group are held by the battery holder so that the positive terminals are on the first tab side in the axial direction of the batteries, and one second battery of the three batteries not belonging to the first group is held by the battery holder so that the positive terminal is on the second tab side in the axial direction of the batteries, the first tab being a tab module including: a first tab part connected to the positive terminal of a third battery that is one of the two first batteries belonging to the first group; and a first intermediate connection tab part connected to the positive terminal of a fourth battery that is the other of the two first batteries belonging to the first group and the negative terminal of the second battery that is not belonging to the first group, The battery pack according to <14>, which is a tab module including: a second intermediate connection tab part connected to the negative terminal of the third battery and the positive terminal of the second battery; and a second tab part connected to the negative terminal of the fourth battery. <16> The battery pack according to <15>, wherein the first tab has a first overlapping portion where the first tab part and the first intermediate connection tab part overlap each other, and the second tab has a second overlapping portion where the second intermediate connection tab part and the second tab part overlap each other. <17>The battery pack according to <16>, wherein the first overlap portion is disposed at a position facing one end of the heat absorption member surrounded by the third battery, the fourth battery, and the second battery, and the second overlap portion is disposed at a position facing the other end of the heat absorption member surrounded by the third battery, the fourth battery, and the second battery. <18> The battery pack according to <16> or <17>, wherein the first tab has a first insulating layer that insulates and separates the first tab part and the first intermediate connection tab part from each other, and the second tab has a second insulating layer that insulates and separates the second intermediate connection tab part and the second tab part from each other. <19> The battery has a positive terminal at one end and a negative terminal at the other end, n is a natural number equal to or greater than 3, the battery holder holds the (2×n+1) batteries in two layers, the (2×n+1) batteries include two first batteries in each of the first to n-th groups, and one second battery that does not belong to any of the first to n-th groups, the two first batteries belonging to the first group are held by the battery holder such that the positive terminals are on the first tab side in the axial direction of the batteries, and in each of the second to n-th groups, one of the first batteries is held by the battery holder such that the positive terminal is on the first tab side in the axial direction of the batteries, and the other first battery is held by the battery holder such that the positive terminal is on the second tab side in the axial direction of the batteries, The one second battery that does not belong to any of the first to n groups is held by the battery holder so that the positive terminal is on the second tab side in the axial direction of the battery, and the first tab comprises: a first tab part connected to the positive terminal of the first battery that belongs to the nth group; and n-1 first intermediate connection tab parts connected to the negative terminal of the first battery that belongs to the kth group (k = 2 to n) and the positive terminal of the first battery that belongs to the k-1th group.The battery pack according to <14>, wherein the battery pack is a tab module including: a second intermediate connection tab part connected to the positive terminal of one of the first batteries belonging to the first group and the negative terminal of the second battery, wherein the second tab part includes: a second tab part connected to the negative terminal of one of the first batteries belonging to the first group; n-1 third intermediate connection tab parts connected to the negative terminal of one of the first batteries belonging to the kth group and the positive terminal of the other of the first batteries belonging to the kth group; and a fourth intermediate connection tab part connected to the negative terminal of the other of the first batteries belonging to the first group and the positive terminal of the second battery. <20> The battery pack according to <19>, wherein the first tab has: a first overlapping portion where the first tab part and the second intermediate connection tab part overlap each other; and n-1 second overlapping portions where two adjacent first intermediate connection tab parts overlap each other; and the second tab has: a third overlapping portion where the second tab part and the fourth intermediate connection tab part overlap each other; a fourth overlapping portion where the fourth intermediate connection tab part and the third intermediate connection tab part overlap each other; and n-2 fifth overlapping portions where two adjacent third intermediate connection tab parts overlap each other. <21> The battery pack according to <19>, wherein the first overlap portion is arranged at a position facing one end of the heat absorption member surrounded by the two first batteries and the one second battery, the n-1 second overlap portions are arranged at a position facing one end of the heat absorption member surrounded by three adjacent first batteries, the third overlap portion is arranged at a position facing the other end of the heat absorption member surrounded by the two first batteries and the one second battery, the fourth overlap portion is arranged at a position facing one end of the heat absorption member surrounded by three adjacent first batteries, and the n-2 fifth overlap portions are arranged at a position facing one end of the heat absorption member surrounded by three adjacent first batteries. <22>The battery pack according to <20> or <21>, wherein the first tab has: a first insulating layer that insulates and separates the first tab part and the second intermediate connection tab part from each other; and a second insulating layer that insulates and separates two adjacent first intermediate connection tab parts from each other; and the second tab has: a third insulating layer that insulates and separates the second tab part and the fourth intermediate connection tab part from each other; a fourth insulating layer that insulates and separates the fourth intermediate connection tab part and the third intermediate connection tab part from each other; and a fifth insulating layer that insulates and separates two adjacent third intermediate connection tab parts from each other. <23> The battery pack according to any one of <1> to <22>, wherein the first tab is formed to cover one end of the one or more heat absorption members and at least a part of one end of each of the batteries when the battery unit is viewed in the axial direction of the batteries, and the second tab is formed to cover the other end of the one or more heat absorption members and at least a part of the other end of each of the batteries when the battery unit is viewed in the axial direction of the batteries. <24> The battery pack according to any one of <1> to <23>, wherein the battery has terminals at one end and the other end, and the battery holder has: a first side plate portion that covers one end of the one or more heat absorption members and covers a portion of one end of each of the batteries excluding at least a portion of the terminals when the battery unit is viewed in the axial direction of the battery, and a second side plate portion that covers the other end of the one or more heat absorption members and covers a portion of the other end of each of the batteries excluding at least a portion of the terminals when the battery unit is viewed in the axial direction of the battery. <25> The battery pack according to any one of <1> to <24>, wherein the battery unit further has a board, and the first tab has a first hook engaged with the board, and the second tab has a second hook engaged with the board.

Claims

1. Multiple batteries, One or more heat-absorbing members having a heat-absorbing agent and a housing for containing the heat-absorbing agent, extending in the axial direction of the battery and arranged adjacent to at least two of the batteries, A battery holder that holds the aforementioned plurality of batteries, A first tab connected to the terminal on one end of the plurality of batteries, A second tab connected to the other end terminal of the aforementioned plurality of batteries and It has a battery unit that has The first tab is formed to cover one end of the one or more heat-absorbing members when the battery unit is viewed from the axial direction of the battery. The second tab is formed to cover the other end of the one or more heat-absorbing members when the battery unit is viewed from the axial direction of the battery. Battery pack.

2. The number of batteries is two, The number of heat-absorbing members is one. The heat-absorbing member is arranged adjacent to the two batteries. The battery pack according to claim 1.

3. The aforementioned battery has a positive terminal at one end and a negative terminal at the other end. The two batteries are held by the battery holder such that their positive terminals face opposite each other in the axial direction of the batteries. The first tab is a tab module having a first tab component connected to the positive terminal of one of the batteries and a second tab component connected to the negative terminal of the other battery. The second tab is a tab module having an intermediate connecting tab component connected to the negative terminal of one of the batteries and the positive terminal of the other battery. The battery pack according to claim 2.

4. The first tab has an overlapping portion where the first tab component and the second tab component overlap each other. The battery pack according to claim 3.

5. The overlapping portion is positioned opposite one end of the heat-absorbing member. The battery pack according to claim 4.

6. The overlapping portion is not positioned opposite one end of the heat-absorbing member, but is positioned only in a position not opposite one end of the heat-absorbing member. The battery pack according to claim 4.

7. The first tab has an insulating layer that insulates and separates the first tab component and the second tab component from each other. The battery pack according to claim 5 or claim 6.

8. 2 × n batteries (where n is an integer greater than or equal to 2), The battery comprises a heat absorbent and a housing for containing the heat absorbent, and n-1 heat absorbent members extending in the axial direction of the battery, A battery holder that holds the aforementioned 2 × n batteries in a hierarchical manner, A first tab connected to one end terminal of the 2 × n batteries, A second tab connected to the other end terminal of the 2 × n batteries, It has a battery unit that has The n-1 heat-absorbing members are arranged one at a time in the n-1 gaps formed by four adjacent batteries in the 2 × n batteries. The first tab is formed to cover one end of each heat-absorbing member when the battery unit is viewed from the axial direction of the battery, The second tab is formed to cover the other end of each heat-absorbing member when the battery unit is viewed from the axial direction of the battery. The battery pack according to claim 1.

9. The aforementioned battery has a positive terminal at one end and a negative terminal at the other end. n is an integer greater than or equal to 4, Of the 2 × n batteries, the n first batteries belonging to the first group are held by the battery holder such that the positive terminal is on the first tab side in the axial direction of the battery. Of the 2 × n batteries, the n second batteries belonging to the second group are held by the battery holder such that the positive terminal is on the second tab side in the axial direction of the battery. The first tab mentioned above is, A first tab component connected to the positive terminal of a plurality of third batteries, which are part of the n first batteries belonging to the first group, A second tab component connected to the negative terminal of a plurality of fourth batteries, which are part of the n second batteries belonging to the second group, A first intermediate connecting tab component connected to the positive terminals of the plurality of fifth batteries other than the plurality of third batteries among the n first batteries belonging to the first group, and to the negative terminals of the plurality of sixth batteries other than the plurality of fourth batteries among the n second batteries belonging to the second group. It is a tab module that has, The second tab is, A second intermediate connecting tab component connected to the negative terminals of the plurality of third batteries and the positive terminals of the plurality of sixth batteries, A third intermediate connecting tab component connected to the positive terminals of the plurality of fourth batteries and the negative terminals of the plurality of fifth batteries. It is a tab module that has The battery pack according to claim 8.

10. The first tab mentioned above is, The first tab component and the first intermediate connecting tab component overlap each other in a first overlapping portion, The second overlap portion where the second tab component and the first intermediate connecting tab component overlap each other It has, The second tab has a third overlap portion where the second intermediate connecting tab component and the third intermediate connecting tab component overlap each other. The battery pack according to claim 9.

11. The first overlap portion is positioned opposite one end of the heat-absorbing member, which is located between the plurality of third batteries connected to the first tab component and the plurality of sixth batteries connected to the first intermediate connecting tab component. The second overlap portion is positioned opposite one end of the heat-absorbing member, which is located between the plurality of fourth batteries connected to the second tab component and the plurality of fifth batteries connected to the first intermediate connecting tab component. The third overlap portion is positioned opposite the other end of the heat-absorbing member, which is located between the plurality of fifth batteries connected to the second intermediate connection tab component and the plurality of sixth batteries connected to the third intermediate connection tab component. The battery pack according to claim 10.

12. The first overlap portion and the second overlap portion are not positioned opposite one end of each heat-absorbing member, but are positioned not opposite one end of each heat-absorbing member. The third overlap portion is not positioned opposite the other end of each heat-absorbing member, but is positioned not opposite the other end of each heat-absorbing member. The battery pack according to claim 10.

13. The first tab has a first insulating layer that insulates and separates the first tab component, the second tab component, and the first intermediate connecting tab component from each other. The second tab has a second insulating layer that insulates and separates the second intermediate connecting tab component and the third intermediate connecting tab component from each other. The battery pack according to claim 11 or claim 12.

14. (2 × n + 1) batteries (where n is an integer greater than or equal to 1), The battery comprises a heat absorbent and a housing for the heat absorbent, and (2 × n - 1) heat absorbent members extending in the axial direction of the battery, A battery holder that holds the (2 × n + 1) batteries in a hierarchical manner, A first tab connected to one end terminal of the (2 × n + 1) batteries, A second tab connected to the other end terminal of the (2 × n + 1) batteries and It has a battery unit that has The (2 × n - 1) heat-absorbing members are arranged one at a time in the (2 × n + 1) batteries, in the n gaps formed by three adjacent batteries. The first tab is formed to cover one end of each heat-absorbing member when the battery unit is viewed from the axial direction of the battery, The second tab is formed to cover the other end of each heat-absorbing member when the battery unit is viewed from the axial direction of the battery. The battery pack according to claim 1.

15. The aforementioned battery has a positive terminal at one end and a negative terminal at the other end. n is 1, Of the three batteries, the two first batteries belonging to the first group are held by the battery holder such that the positive terminal is on the first tab side in the axial direction of the battery. Of the three batteries, one second battery that does not belong to the first group is held by the battery holder such that its positive terminal faces the second tab in the axial direction of the battery. The first tab mentioned above is, A first tab component connected to the positive terminal of a third battery, which is one of the two first batteries belonging to the first group, A first intermediate connecting tab component connected to the positive terminal of the fourth battery, which is the other of the two first batteries belonging to the first group, and to the negative terminal of the second battery, which does not belong to the first group, It is a tab module that has, The second tab is, A second intermediate connecting tab component connected to the negative terminal of the third battery and the positive terminal of the second battery, The second tab component connected to the negative terminal of the fourth battery and It is a tab module that has The battery pack according to claim 14.

16. The first tab has a first overlap portion in which the first tab component and the first intermediate connecting tab component overlap each other. The second tab has a second overlap portion in which the second intermediate connecting tab component and the second tab component overlap each other. The battery pack according to claim 15.

17. The first overlap portion is positioned opposite one end of the heat-absorbing member, which is surrounded by the third battery, the fourth battery, and the second battery. The second overlap portion is positioned opposite the other end of the heat-absorbing member, which is surrounded by the third battery, the fourth battery, and the second battery. The battery pack according to claim 16.

18. The first tab has a first insulating layer that insulates and separates the first tab component and the first intermediate connecting tab component from each other. The second tab has a second insulating layer that insulates and separates the second intermediate connecting tab component and the second tab component from each other. The battery pack according to claim 16 or claim 17.

19. The aforementioned battery has a positive terminal at one end and a negative terminal at the other end. n is a natural number greater than or equal to 3, The battery holder holds the (2 × n + 1) batteries in two layers, In the (2 × n + 1) batteries, each group from the first to the nth group contains two first batteries, and each group contains one second battery that does not belong to any of the groups from the first to the nth group. The two first batteries belonging to the first group are held by the battery holder such that the positive terminal is on the first tab side in the axial direction of the battery. In each of the groups from the second group to the n group, one of the first batteries is held by the battery holder such that its positive terminal faces the first tab in the axial direction of the battery, and the other of the first batteries is held by the battery holder such that its positive terminal faces the second tab in the axial direction of the battery. The single second battery that does not belong to any of the groups from the first group to the n group is held by the battery holder such that the positive terminal is on the second tab side in the axial direction of the battery, The first tab mentioned above is, A first tab component connected to the positive terminal of the first battery belonging to the n group, n-1 first intermediate connecting tab components connected to the negative terminal of the first battery belonging to the group k (any of k = 2 to n) and the positive terminal of the first battery belonging to the group k-1, A second intermediate connecting tab component is connected to the positive terminal of one of the two first batteries belonging to the first group and to the negative terminal of the second battery, It is a tab module that has, The second tab is, A second tab component connected to the negative terminal of one of the first batteries belonging to the first group, n-1 third intermediate connecting tab components connected to the negative terminal of one of the first batteries belonging to the group k (k = any of 2 to n) and the positive terminal of the other first battery belonging to the group k, A fourth intermediate connecting tab component connected to the negative terminal of the other first battery belonging to the first group and the positive terminal of the second battery, It is a tab module that has The battery pack according to claim 14.

20. The first tab mentioned above is, The first tab component and the second intermediate connecting tab component overlap each other in a first overlapping portion, Two adjacent first intermediate connecting tab components have n-1 second overlapping portions that overlap each other. It has, The second tab is, The second tab component and the fourth intermediate connecting tab component overlap each other in a third overlapping portion, The fourth intermediate connecting tab component and the third intermediate connecting tab component overlap each other in a fourth overlapping portion, Two adjacent third intermediate connecting tab components have n-2 fifth overlapping portions that overlap each other. has The battery pack according to claim 19.

21. The first overlap portion is positioned opposite one end of the heat-absorbing member, which is surrounded by the two first batteries and the one second battery. The n-1 second overlapping portions are positioned opposite one end of the heat-absorbing member surrounded by three adjacent first batteries. The third overlap portion is positioned opposite the other end of the heat-absorbing member surrounded by the two first batteries and the one second battery. The fourth overlap portion is positioned opposite one end of the heat-absorbing member surrounded by three adjacent first batteries, The n-2 fifth overlapping portions are positioned opposite one end of the heat-absorbing member, which is surrounded by three adjacent first batteries. The battery pack according to claim 19.

22. The first tab mentioned above is, A first insulating layer that insulates and separates the first tab component and the second intermediate connecting tab component from each other, A second insulating layer that insulates and separates two adjacent first intermediate connecting tab components from each other. It has, The second tab is, A third insulating layer that insulates and separates the second tab component and the fourth intermediate connecting tab component from each other, A fourth insulating layer that insulates and separates the fourth intermediate connecting tab component and the third intermediate connecting tab component from each other, A fifth insulating layer that insulates and separates two adjacent third intermediate connecting tab components from each other. has The battery pack according to claim 20 or claim 21.

23. The first tab is formed such that, when the battery unit is viewed from the axial direction of the battery, it covers one end of the one or more heat-absorbing members and at least a portion of one end of each of the batteries. The second tab is formed such that, when the battery unit is viewed from the axial direction of the battery, it covers the other end of the one or more heat-absorbing members and at least a portion of the other end of each battery. The battery pack according to claim 1.

24. The aforementioned battery has terminals at one end and the other end, The aforementioned battery holder is When the battery unit is viewed from the axial direction of the battery, it includes a first side plate portion that covers one end of the one or more heat-absorbing members and covers one end of each battery, excluding at least a portion of the terminals, When the battery unit is viewed from the axial direction of the battery, a second side plate portion covers the other end of the one or more heat-absorbing members and covers the other end of each battery, excluding at least a portion of the terminals. has The battery pack according to claim 1.

25. The aforementioned battery unit further comprises a circuit board, The first tab has a first hook that is locked to the substrate, The second tab has a second hook that is locked to the substrate. The battery pack according to claim 1.