Battery pack

Abstract

The present invention prevents battery cells from sinking into an uncured adhesive while enabling replacement of the battery cells. This battery pack comprises: a plurality of battery cells 1 each having a pair of cell end surfaces 1a, 1b and a cell side surface 1c; a battery holder 10 that holds the plurality of battery cells 1 arranged side by side in the cell side surface 1c direction with orientations of the cell end surfaces 1a, 1b aligned; an adhesive 30 that detachably adheres the battery cells 1 to the battery holder 10; and cell support portions 20 that prevent the battery cells 1 from sinking into the adhesive 30. The battery holder 10 has a holder opening window 15 through which the cell end surfaces 1b are exposed, the adhesive 30 in the holder opening window 15 adheres one of the pair of cell end surfaces 1a, 1b of the battery cells 1 to the battery holder 10, and each of the cell support portions 20 has an abutment portion 21 that abuts on the one of the pair of cell end surfaces 1a, 1b.

Description

Battery pack

[0001] The present disclosure relates to a battery pack.

[0002] Conventionally, battery packs in which a battery cell and a battery holder are fixed with an adhesive have been developed (e.g., Patent Document 1). A battery pack has a configuration in which an adhesive is applied and disposed at the central portion of the cell side surface of a battery cell to firmly fix the battery cell and the battery holder. However, this battery pack has a problem that the battery cell cannot be replaced. It cannot cope with the replaceability of battery cells required by EU regulations and for reducing environmental impact, which has been increasingly demanded in recent years. In addition, there are many locations where adhesive needs to be applied, for example, applying adhesive one point at a time with a nozzle to a battery holder or the central portion of the cell side surface of each battery cell, which requires labor, time and man-hours, leading to a problem of increased manufacturing costs. Furthermore, there is also a problem that the adhesive has little contribution to heat dissipation.

[0003] Japanese National Publication of International Patent Application No. 2011-508366

[0004] The present disclosure has been developed for the purpose of further solving the above problems, and one object of the present disclosure is to provide a battery pack in which battery cells can be replaced. Another object is to provide a battery pack that can reduce and suppress manufacturing costs. Still another object is to provide a battery pack that can improve the contribution of the adhesive to heat dissipation. It should be noted that the description of these objects and problems in the present disclosure does not preclude the existence of other objects and problems. In addition, one aspect of the present disclosure does not need to solve all of these problems. Furthermore, other problems can be extracted from the description of the specification, drawings, and claims of the present disclosure.

[0005] A battery pack according to one embodiment of the present disclosure comprises a plurality of battery cells, each having a pair of cell end faces and a cell side surface connecting the cell end faces; a battery holder that holds the plurality of battery cells in a line in the direction of the cell side surfaces with the orientation of the cell end faces aligned; an adhesive that detachably adheres the battery cells to the battery holder; and a cell support portion that prevents the battery cells from sinking into the adhesive. The battery holder has a holder opening window that exposes the cell end faces, the adhesive is placed in the holder opening window and adheres one of the pair of cell end faces of the battery cell to the battery holder, and the cell support portion has a contact portion that abuts against one of the pair of cell end faces.

[0006] A battery pack according to one embodiment of this disclosure has the advantage of enabling the replacement of battery cells. It also has the advantage of reducing and controlling manufacturing costs. Furthermore, it has the advantage of improving the contribution of the adhesive to heat dissipation.

[0007] This is a schematic perspective view of a battery pack according to one embodiment. This is an exploded perspective view of the battery pack of Figure 1. This is a schematic perspective view showing the battery pack of Figure 1 with the upper split case removed. This is a schematic perspective view of the split holder as seen from the bottom side (lower side). This is a schematic plan view of the split holder of Figure 4 as seen from above. This is a schematic bottom view of the split holder of Figure 4 as seen from below. This is a schematic cross-sectional view of Figure 3 along the line VII-VII. This is an enlarged schematic cross-sectional view of Figure 7. Figure 9A is a schematic perspective view showing one embodiment of the cell support part, Figure 9B is a plan view, and Figure 9C is a bottom view. Figure 10A is a schematic perspective view showing another embodiment of the cell support part, Figure 10B is a plan view, and Figure 10C is a bottom view. Figure 11A is a schematic perspective view showing another embodiment of the cell support part, Figure 11B is a plan view, and Figure 11C is a bottom view. Figure 12A is a schematic perspective view showing another embodiment of the cell support part, Figure 12B is a plan view, and Figure 12C is a bottom view. Figure 13A is a schematic perspective view showing another embodiment of a battery holder and cell support with side adhesive portions, Figure 13B is a plan view, and Figure 13C is a bottom view. This is a schematic bottom view showing a battery holder with side adhesive portions. This is a schematic perspective view showing the outer casing and heat dissipation portion with continuous adhesive applied.

[0008] The form of this disclosure may be specified by the following configurations and features.

[0009] A battery pack according to one embodiment of the present disclosure comprises a plurality of battery cells, each having a pair of cell end faces and a cell side surface connecting the cell end faces; a battery holder that holds the plurality of battery cells aligned in the direction of the cell side surfaces with the orientation of the cell end faces aligned; an adhesive that detachably adheres the battery cells to the battery holder; and a cell support portion that prevents the battery cells from sinking into the adhesive. The battery holder has a holder opening window that exposes the cell end faces, the adhesive is placed in the holder opening window and adheres one of the pair of cell end faces of the battery cell to the battery holder, and the cell support portion has a contact portion that abuts against one of the pair of cell end faces. In this disclosure, "one of the pair of cell end faces of the battery cell" refers to either one of the pair of cell end faces and does not specify which one.

[0010] The above configuration has the advantage of enabling the replacement of battery cells. This is because the adhesive detachably bonds the battery cells and secures them to the battery holder, and in addition, the adhesive is placed and applied to one of the pair of cell end faces (cell bottom face) of the battery cell. Furthermore, the above configuration has the advantage of facilitating the attachment and replacement of specific battery cells by placing and applying the adhesive to one of the cell end faces (cell bottom face). Furthermore, the above configuration has the advantage of reducing and suppressing manufacturing costs. This is because the battery pack has a simple structure, and the effort, labor, and time required to place and supply the adhesive to one of the pair of cell end faces (cell bottom face side) of the battery cell can be reduced, simplifying the assembly and manufacturing process. Moreover, the above configuration has the advantage of improving the contribution of the adhesive to heat dissipation. This is because the heat generated by the battery cell can be dissipated and cooled through the adhesive placed on one side (the bottom side) of the pair of cell end faces of the battery cell, and the contribution of the adhesive to heat dissipation can be improved by filling the insulating space with the adhesive, and further improvements can be made to the contribution to heat dissipation by the material and contents of the adhesive. In addition, by placing a heat dissipation section on one side (the bottom side) of the pair of cell end faces of the battery cell, heat dissipation and cooling can be further improved, and the contribution of the adhesive to heat dissipation can be improved.

[0011] Furthermore, the above configuration has the advantage of allowing battery cells to be replaced while preventing the battery cells from sinking into the uncured adhesive. This is because the battery pack is equipped with a cell support part that prevents the battery cells from sinking, and the contact part contacts the pair of cell end faces (cell bottom faces) of the battery cell, preventing the battery cell from sinking into the adhesive. Furthermore, the above configuration has the advantage of improving vibration resistance and shock resistance. This is because the cell support part prevents one side of the pair of cell end faces (cell bottom side) of the battery cell from sinking, falling in, or getting embedded in the uncured adhesive, and the adhesive can harden and fix without creating a gap between the other side (top side) of the pair of cell end faces of the battery cell and the battery holder, thus preventing the battery cell from coming off, the lead plates from being damaged or broken due to vibration, shock, etc. The battery pack has a problem where, before the adhesive hardens, the battery cells sink into the uncured adhesive due to their own weight, as well as being pressed into the adhesive by jigs during assembly and welding. This causes the battery cells to drop down in a vertical position, creating a gap between the top of the battery cell and the battery holder. Furthermore, vibration and shock can cause the battery cells to rattle within the gap, leading to the battery cells becoming detached and the lead plates breaking or being damaged. In particular, because a strong adhesive cannot be used to bond the battery cells in a detachable manner, the above problems are more likely to occur due to vibration and other factors. The above configuration solves these problems, allows for battery cell replacement, prevents the battery cells from sinking into the uncured adhesive, and allows for bonding and fixing of the battery cell end faces to the battery holder without creating gaps, thus improving vibration resistance and shock resistance. Furthermore, this configuration has the advantage that the cell support section acts as a spacer, supporting the battery cell in a predetermined position and height, and enabling stable adhesion and curing of the adhesive while the battery cell is positioned in the predetermined location and orientation.

[0012] Furthermore, in addition to the above-described embodiments, battery packs according to other embodiments of this disclosure may have an elastically deformable cell support portion. The above configuration has the advantage that the cell support portion having an elastic portion can support the battery cell in a predetermined position and height in an elastically deformable manner, and can prevent the battery cell from sinking into or becoming embedded in the uncured adhesive. The above configuration has the advantage that the contact pressure of the contact portion can be set and adjusted, and the contact portion can contact one of the pair of cell end faces of the battery cell with a contact pressure within a predetermined range. The above configuration has the advantage that the elastic portion of the cell support portion can support the battery cell in a predetermined position, height and orientation while absorbing tolerances in the components and assembly of the battery holder, battery cell, etc.

[0013] Furthermore, in addition to the above-described embodiment, a battery pack according to another embodiment of the present disclosure has a battery holder composed of a plurality of divided holders divided in the axial direction of the battery cell, and the divided holder may have a first divided holder and a second divided holder. The first divided holder and the second divided holder each have an insertion tube that opens to accommodate each battery cell, and when the first divided holder and the second divided holder are connected, one of the pair of cell end faces of the battery cell may abut against the inner end of the insertion tube of the first divided holder or the second divided holder, and the other of the pair of cell end faces of the battery cell may abut against the contact portion. The above configuration has the advantage that it can prevent the battery cell from getting stuck in the uncured adhesive, can bond one of the pair of cell end faces of the battery cell to the battery holder without creating a gap, and can improve vibration resistance and shock resistance. This is because, when the first and second divider holders are connected, one of the pair of cell end faces of the battery cell abuts against the inner end of the insertion tube of either the first or second divider holder, and the other of the pair of cell end faces of the battery cell abuts against the contact point.

[0014] Furthermore, in addition to the above-described embodiment, a battery pack according to another embodiment of this disclosure has a cell support portion that is connected to a contact portion and has a non-contact portion that does not contact the bottom surface of the battery cell, and the non-contact portion can be connected to a battery holder. The above configuration has the advantage that an adhesive can be interposed between the non-contact portion and the bottom surface of the cell, thereby expanding the adhesive area and adhesive region both planarly and three-dimensionally, and the adhesive can adhere around the contact portion adjacent to the contact portion, improving adhesion and the stable attachment and detachment of the battery cell.

[0015] Furthermore, in addition to the above-described form, battery packs according to other embodiments of this disclosure may have a height difference between the contact portion and the non-contact portion facing the cell bottom surface. The above configuration has the advantage that the contact portion contacts the cell bottom surface, preventing the battery cell from sinking into the adhesive while supporting the battery cell in a predetermined position, height, and orientation, and that the adhesive can be interposed between the non-contact portion and the cell bottom surface, thereby supporting the battery cell and achieving stable adhesion and detachability of the battery cell.

[0016] Furthermore, in addition to the above-described embodiment, a battery pack according to another embodiment of this disclosure may have a plurality of spaced-apart contact portions in the cell support portion. This configuration has the advantage that the contact portions contact the bottom surface of the cell, preventing the battery cell from sinking into the adhesive, while supporting the battery cell in a predetermined position, height, and orientation, and increasing the adhesive area.

[0017] Furthermore, in addition to the above-described form, a battery pack according to another embodiment of this disclosure has a contact portion that can contact the peripheral edge of the cell bottom surface. The above configuration has the advantage that the cell support portion can be positioned and connected close to the outer periphery of the holder opening window of the battery holder, the structure and configuration of the cell support portion can be simplified and made smaller, and costs can be reduced. It also has the advantage of preventing and suppressing the effects of damage to the battery holder caused by swelling of the cell bottom surface that may occur with aging. Note that the peripheral edge of the cell bottom surface refers to the area other than the center of the cell bottom surface, and closer to the outer edge than the center of the cell bottom surface.

[0018] Furthermore, in addition to the above-described embodiments, battery packs according to other embodiments of this disclosure may use a thermally conductive adhesive containing a thermally conductive filler. The above configuration has the advantage that the thermally conductive adhesive efficiently dissipates and cools the heat of the battery cells, thereby improving the contribution of the adhesive to heat dissipation.

[0019] Furthermore, in addition to the above-described form, a battery pack according to another embodiment of this disclosure allows for the continuous arrangement of adhesive for bonding multiple adjacent battery cells to the battery holder. This configuration allows for the continuous arrangement of adhesive for bonding multiple adjacent battery cells, for example, in a single stroke or linearly, thereby bonding and fixing each battery cell to the battery holder. This eliminates the need to apply and place adhesive for each battery cell, significantly reducing the effort involved in the adhesive application, bonding, and assembly processes, shortening the time required, simplifying the process and man-hours, and reducing and suppressing manufacturing costs. Adhesive for bonding all or some of the battery cells can be applied, placed, and supplied continuously.

[0020] Furthermore, in addition to the above-described embodiments, battery packs according to other embodiments of this disclosure may have a battery holder having a side adhesive portion that forms an adhesive area where adhesive can be present and positioned, and which is continuously bonded to the cell side surface, and which is bonded to the cell bottom surface. With this configuration, an adhesive area that can be continuously bonded to the cell end surface and the cell side surface is formed, and the battery cell can be bonded to the battery holder with adhesive that is continuous between the cell end surface and the cell side surface. With this configuration, the adhesive can be continuously bonded to the battery cell and the battery holder on different vertical surfaces and directions, with the adhesive on the cell bottom surface and the cell side surface being different, and horizontal displacement can be effectively prevented. In addition, with this configuration, if more adhesive than necessary is supplied to the cell bottom surface, the amount of adhesive on the cell bottom surface can be adjusted to an appropriate amount, and the excess can be released and supplied to the side adhesive portion on the cell side surface, thus being able to accommodate variations in the amount of adhesive applied.

[0021] Furthermore, battery packs according to other embodiments of this disclosure, in addition to the above-described forms, further have a heat dissipation section for cooling the battery cells, and the heat dissipation section can be bonded to the battery cells with an adhesive. The above configuration has the advantage of improving the contribution of the adhesive to heat dissipation and efficiently improving the heat dissipation and cooling performance of the battery cells.

[0022] The embodiments of this disclosure will be described below with reference to the drawings. However, the embodiments shown below are examples for concretizing the technical concept of this disclosure, and this disclosure is not limited to the following. Furthermore, this specification does not limit the members shown in the claims to the members of the embodiments. In particular, the dimensions, materials, shapes, relative arrangements, etc. of the components described in the embodiments are not intended to limit the scope of this disclosure to those, unless specifically stated otherwise, but are merely illustrative examples. Note that the size and positional relationships of the members shown in each drawing may be exaggerated for clarity of explanation. Furthermore, in the following description, the same name and reference numerals indicate the same or similar members, and detailed explanations are omitted as appropriate. Furthermore, each element constituting this disclosure may be configured such that multiple elements are made of the same member, with one member serving multiple elements, or conversely, the function of one member may be shared among multiple members.

[0023] The battery pack disclosed herein can be used as a power source for electric motorcycles, electric scooters, electric assist bicycles, hybrid vehicles, electric vehicles, electric carts, forklifts, construction machinery, etc. It can also be used as a power source for portable electrical equipment such as power tools, electric cleaners, and wireless devices. It can be used as a portable and replaceable power source, and can also be used as a stationary power storage power source for servers, or as a battery pack for home, business, and factory use. The battery pack is particularly useful as a power source for electrical equipment and products that require high vibration and shock resistance. Below, as one embodiment of the herein, a portable battery pack used as a drive power source for an electric two-wheeled vehicle will be illustrated and described. [Embodiment 1]

[0024] Figures 1 to 3 show a battery pack 100 according to Embodiment 1 of the present disclosure. In these figures, Figure 1 is a schematic perspective view showing the external appearance of the battery pack 100, Figure 2 is an exploded perspective view of the battery pack 100 of Figure 1, and Figure 3 is a schematic perspective view with the upper first split case 51A removed. Furthermore, Figure 4 is a schematic perspective view of the battery holder 10 (second split holder 11B) viewed from the holder bottom surface 14 side (bottom side), Figure 5 is a schematic plan view of the second split holder 11B viewed from above, Figure 6 is a schematic bottom view of the second split holder 11B viewed from below, Figure 7 is a schematic cross-sectional view along the line VII-VII in Figure 3, Figure 8 is an enlarged schematic cross-sectional view of Figure 7, Figures 9A to 9C are schematic perspective views, plan views, and bottom views showing one embodiment of the cell support part 20, and Figures 10A to 10C are schematic perspective views, plan views, and bottom views. Figures 11A to 11C and 12A to 12C show schematic perspective views, plan views, and bottom views of other embodiments of the cell support portion 20. Figures 13A to 13C show schematic perspective views, plan views, and bottom views of other embodiments of the battery holder 10 having side adhesive portions 17. Figure 14 is a schematic bottom view of the battery holder 10 having side adhesive portions. Figure 15 is a schematic perspective view showing the state in which adhesive 30 is applied continuously to the outer case 50 and the heat dissipation portion 40. Note that Figures 7 and 8 are schematic cross-sectional views for illustrative purposes, and the arrangement, length, etc. of the cell support portion 20 are not accurate. In the schematic cross-sectional view, the battery holder 10 has a pair of cell support portions 20 on the holder bottom surface 14 that protrude inward from the outer peripheral portions 15a on both sides of the holder opening window 15.

[0025] The battery pack 100 shown in these figures comprises a plurality of battery cells 1, a battery holder 10 that holds the plurality of battery cells 1, an adhesive 30 that adheres each battery cell 1 to the battery holder 10, and a cell support portion 20 that prevents each battery cell 1 from sinking into the adhesive 30. (Outer case 50)

[0026] The battery pack 100 can be housed in the outer case 50. This disclosure does not specify the shape, number of divisions, division positions, structure, configuration, connection method, etc. of the outer case 50 (divided case 51), but the outer case 50 illustrated in Figures 1 and 2 has a box-shaped exterior and a hollow interior, and has a storage section for housing a core pack having a plurality of battery cells 1 held by a battery holder 10. The outer case 50 can be composed of two or more divided cases 51. The divided cases 51 can be closed by housing the core pack in the storage section from the case opening surface, connecting, fitting, etc., and can be fixed with bolts, etc. The divided cases 51 in Figures 1 and 2 have a pair of divided cases 51, with the upper one being the first divided case 51A and the lower one being the second divided case 51B. The first and second divided cases 51A and 51B each have an opening surface and are connected to close them. The divided case 51 may be constructed as a single unit beforehand, or it may be constructed by dividing it vertically or horizontally, or by combining and connecting multiple plate materials. The outer case 50 can be made of a resin such as polycarbonate or ABS to improve insulation. Alternatively, it can be made of a material with excellent strength and heat dissipation, such as metal. (Battery cell 1)

[0027] The battery cell 1 is a rechargeable battery, and can be a cylindrical or rectangular battery cell 1. The battery cell 1 in Figure 2 is a cylindrical battery with a cylindrical outer casing. The battery cell 1 can use any known, commercially available, or future-developed rechargeable battery, such as lithium-ion rechargeable batteries, nickel-metal hydride batteries, nickel-cadmium batteries, or all-solid-state batteries. Each battery cell 1 has a pair of cell end faces 1a and 1b, and a cell side surface 1c connected to the cell end faces 1a and 1b and located between them. The battery cell 1 has a pair of cell electrodes, i.e., a positive electrode and a negative electrode. The terminals of the positive or negative cell electrodes are provided on one or both of the cell end faces 1a and 1b of the battery cell 1. In Figure 7, each battery cell 1 has the positive and negative cell electrodes exposed on one of the cell end faces 1a. The battery cell 1 can have a positive electrode terminal of a sealing body on one of the cell end faces 1a, and the outer casing insulated from this can be used as the negative electrode. Furthermore, the battery cell 1 can also have one cell end face 1a or 1b facing the positive electrode and the other cell end face 1b or 1a facing the negative electrode.

[0028] This disclosure does not specify the number, arrangement, connection, structure, etc., of the battery cells 1, and any number, arrangement, connection, structure, etc., can be adopted as appropriate. For example, cylindrical battery cells 1 may be arranged in a manner in which the cell end faces 1b form a matrix. The matrix-shaped battery cells 1 can be arranged in any manner, such as arranging the cell end faces 1b in a grid pattern or in a staggered pattern with adjacent cell end faces 1b offset. A gas outlet that opens in response to the pressure rise inside the battery cell 1 is provided on the cell end face 1a, etc., and a safety valve or a sealing body with a notch to open the open end can be used for the gas outlet.

[0029] Multiple battery cells 1 are connected in series or parallel via one or more lead plates 5. The lead plates 5 connect the multiple battery cells 1 housed in the battery holder 10 in series or parallel. The number of battery cells 1 and the connection configuration, i.e., the number of series and parallel connections, are not limited to this configuration and can be arbitrarily set according to the required specifications. The lead plates 5 can be made of a metal plate with excellent conductivity, such as an aluminum plate, a nickel plate, a copper plate, or an alloy containing any of these.

[0030] The multiple lead plates 5 in Figure 2 are each connected to one end face 1a of each battery cell 1 held in the battery holder 10, electrically connecting the battery cells 1 to each other. In Figure 7, the lead plates 5 are fixed and held on the upper surface of the battery holder 10, and each lead plate 5 has a lead opening window at a position facing the end face 1a of the battery cell 1, with a current collecting tab protruding from the lead opening window. The current collecting tab is a component for connecting to the cell electrode on the end face 1a of the battery cell 1. Each current collecting tab is bent in the middle and protrudes diagonally downward, which allows for some positional misalignment and adjustment of the fixing position and height with respect to the cell electrode. In Figure 7, the lead plates 5 are arranged on one side of the upper surface of the battery holder 10 for one-sided current collection, and a heat dissipation section 40 such as a cooling plate or heat sink is placed on the opposite side of the holder bottom surface 14 of the battery holder 10 to improve heat dissipation and cooling performance, and to facilitate the removal of the battery cells 1.

[0031] The battery pack 100 may have a circuit board 3 connected via lead plates 50. The circuit board 3 can implement, for example, a charge / discharge circuit for charging and discharging the battery cells 1, and a protection circuit that monitors the voltage, current, and temperature of the battery cells 1 and cuts off the current in case of abnormalities. (Battery holder 10)

[0032] The battery holder 10 holds a plurality of battery cells 1. The battery holder 10 has a storage section for inserting and housing the battery cells 1 whole or partially. The battery holder 10 can be made of materials with excellent insulating properties, such as thermoplastic resins such as m-PPE (modified polyphenylene ether), ABS resin, PC (polycarbonate), PP (polypropylene), and PBT (polybutylene terephthalate), or thermosetting resins such as silicone resin, unsaturated phenolic resin, and unsaturated polyester.

[0033] The battery holder 10 can be composed of one or more divided holders 11. The battery holder 10 illustrated in Figure 2 is composed of a pair of divided holders 11 that are divided in the axial direction of the battery cell 1. The divided holder 11 has a first divided holder 11A and a second divided holder 11B, and holds each battery cell 1 in a vertical position. The battery holder 10 (first and / or second divided holders 11A, 11B) has an insertion tube 12 that opens to allow each battery cell 1 to be individually inserted and stored. The first and second divided holders 11A and 11B each have an insertion tube 12 that opens to allow each battery cell 1 to be individually inserted and stored, and a holder end face 13 that connects the multiple insertion tubes 12 on one end face side. The first and second split holders 11A and 11B constitute a storage section of the cell storage space for housing the battery cell 1, and the first and second split holders 11A and 11B are connected to sandwich the battery cell 1 between them. When the first split holder 11A and the second split holder 11B are connected, one of the pair of cell end faces 1a and 1b of the battery cell 1 at least partially abuts against the inner end 12b inside the insertion cylinder 12 of the first split holder 11A or the second split holder 11B, and the other of the pair of cell end faces 1a and 1b of the battery cell 1 abuts against the contact portion 21. In Figure 8, the cell end face 1a of the battery cell 1 abuts against the inner end 12b of the insertion cylinder 12 of the first divider holder 11A, and the cell end face 1b (cell bottom face 2) abuts against the contact portion 21 of the inner end 12b of the insertion cylinder 12 of the second divider holder 11B. The battery cell 1 is held between the first and second divider holders 11A and 11B by its cell end faces 1a and 1b on both sides, and is held in contact with the battery holder 10 without any gaps between the battery cell 1 and the battery holder 10. Each cell storage space is individually isolated by the cylindrical side surface 12a of the isolation wall inside the insertion cylinder 12 so that adjacent battery cells 1 do not come into contact with each other. The first and second divider holders 11A and 11B can be formed integrally. The battery holder 10 covers part or all of the opposing cell end faces 1a and 1b and cell side surface 1c of each battery cell 1.

[0034] The battery holder 10 in Figure 7 arranges multiple battery cells 1 in a vertical position, with the orientation of the cell end faces 1a and 1b aligned and the direction of the cell side faces 1c. As shown in Figure 7, the battery holder 10 can be arranged side by side with each cell end face 1a and 1b on the same plane, or the cell end faces 1a and 1b can be arranged with steps or height differences. In Figure 7, the cell electrodes are arranged on the same side, and the positive and negative cell electrodes of each battery cell 1 are placed on the upper side. The vertical position of the battery cells 1 is based on the position in which the uncured adhesive 30 is placed below the battery cells 1 during assembly. In the battery pack 100 in Figures 3 and 7, the battery cells 1 are in a vertical position when laid flat, but the vertical position of the battery cells 1 does not need to be maintained when the battery pack 100 is laid flat or when it is installed or stored in an electrical device.

[0035] The battery holder 10 has a holder opening window 15 that opens opposite to the cell end face 1b of each battery cell 1 inserted and stored inside, allowing the cell end face 1b to be exposed through the holder opening window 15. The holder opening window 15 can be provided to connect the cell electrodes to the lead plate 5. The battery holder 10 in Figure 2 has a holder opening window 15 on its upper surface, allowing the cell electrodes to be exposed from each cell end face 1a through the holder opening window 15 and connected to the lead plate 5. The holder end face 13 of the first divided holder 11A positions, locks, and holds the lead plate 5 in a predetermined position, and connects the lead plate 5 to the cell electrodes through the holder opening window 15. The battery holder 10 can also have a holder opening window 15 on the holder bottom surface 14 side that is not connected to the lead plate 5. The second divided holder 11B in Figure 4, etc., has a holder opening window 15 opening on the holder bottom surface 14 opposite to the cell bottom surface 2 of the battery cell 1. The second split holder 11B opens a holder opening window 15 without blocking the holder bottom surface 14, allowing the battery cell 1 to be detachably bonded by placing adhesive 30 in the holder opening window 15. This also simplifies the application and placement process of the adhesive 30. Furthermore, the adhesive 30 adheres tightly to the heat dissipation section 40 without any heat-insulating gaps, creating a thermal bond with the heat dissipation section 40 and improving heat dissipation and cooling efficiency. In addition, a cell support section 20 is provided in the holder opening window 15, supporting the battery cell 1 in a predetermined position and orientation without hindering detachable adhesion or efficient heat dissipation and cooling, preventing it from falling into or sinking into the uncured adhesive 30. The holder opening window 15 can have the same or different shapes and sizes on the upper side and the holder bottom surface 14 side of the battery holder 10.

[0036] The battery holder 10 (second divided holder 11B) is provided with a holder opening window 15 that opens into the holder bottom surface 14, facing the bottom surface 2 of each cell. The holder opening window 15 opens according to the shape, size, arrangement, etc., of the cell bottom surface 2 of the battery cell 1. In Figure 4, etc., the holder opening window 15 is circular, the same as the shape of the cell bottom surface 2 of a cylindrical battery. The holder opening window 15 can open to the same or different size as the cell bottom surface 2, and can open to a shape similar to the cell bottom surface 2. Each battery cell 1 exposes its cell bottom surface 2 through the holder opening window 15, and the adhesive 30 of the holder opening window 15 adheres the battery holder 10 and the battery cell 1. The holder opening window 15 has an opening area, shape, diameter, etc., that ensures appropriate adhesive strength and stable attachment and detachment of the battery cell 1. A wider opening area can achieve adhesive strength and stable attachment and detachment of the battery cell 1. The opening area of ​​the holder opening window 15 on the holder bottom surface 14 can be, for example, 40% or more, 50% or more, 60% or more, 70% or more, 80% or more, or 90% or more of the area of ​​the cell bottom surface 2.

[0037] The battery holder 10 is provided with an adhesive area 16 that adheres to the battery cell 1, such as between it and the battery cell 1. Adhesive 30 is placed in the adhesive area 16 to bond the battery holder 10 and the battery cell 1. The adhesive area 16 may have a bottom adhesive area 16X to which the battery holder 10 adheres to the bottom surface 2 of the cell, and may also have a side adhesive area 16Y to which it adheres to the side surface 1c of the cell. The bottom adhesive area 16X is a gap where the adhesive enters and exists to bond the battery holder 10 and the bottom surface 2 of the cell, and includes the space between the non-contact portion 22 and the cell end surface 1b. The battery holder 10 may have a side adhesive portion 17 that forms the side adhesive area 16Y. One or more side adhesive portions 17 may be provided at the lower end of the cylindrical side surface 12a and / or the bottom surface 14 of the holder, and can communicate with the bottom adhesive area 16X to expand the adhesive area to the side surface 1c of the cell in addition to the bottom surface 2 of the cell. Furthermore, the side bonding portion 17 allows the adhesive 30 to continuously wrap around the cell side 1c in a vertical direction, which is different from the cell bottom surface 2, and to embrace and bond with the cell bottom surface 2 and the cell side 1c, thereby improving the bonding strength with the battery cell 1 and stably holding the battery cell 1 in a predetermined position and orientation. It also enables stable attachment and detachment of the battery cell 1 while weakening the adhesive strength of the adhesive 30. Moreover, the battery holder 10 having the side bonding portion 17 provides a relief area for excess or overflowing adhesive 30 from the bottom bonding region 16X, allowing it to accommodate variations in the amount of adhesive 30 applied. The side bonding portion 17 can be any shape or structure that allows the adhesive 30 to be placed on the cell side 1c side, such as a recess, relief groove, notch, gap, step, or tapered surface.

[0038] The side adhesive portion 17 illustrated in Figures 13A to 13C and Figure 14 has a step between it and the holder bottom surface 14 and the lower surface of the non-contact portion 11, and also has a notch in the axial direction of the battery cell 1, forming a side adhesive region 16Y that opens to the cylindrical side surface 12a and communicates with the bottom adhesive region 16X. The step and notch have a stepped surface that is higher than the holder bottom surface 14 and the lower surface of the non-contact portion 11, and the step and notch open to the cylindrical side surface 12a, communicating the bottom adhesive region 16X and the side adhesive region 16Y (Figure 13A). The stepped surface can be a flat surface, a curved surface, an inclined surface, a tapered surface, a groove, an uneven surface, a notch, etc. Furthermore, Figures 13C and 14 show that multiple side adhesive portions 17 are provided between adjacent non-contact portions 22E1 to 22E6 (cell support portions 20E1 to 20E6) (6 in Figures 13C and 14), extending and expanding the stepped surface in a planar manner toward the adjacent battery cell 1, and integrating and becoming identical with the side adhesive region 16Y of the cell side surface 1c of the adjacent battery cell 1. The multiple side adhesive regions 16Y are in communication with the bottom adhesive region 16X, allowing the adhesive 30 to enter any of the side adhesive regions 16Y from the bottom adhesive region 16X, and the adhesive 30 can fill the adhesive region (especially the bottom adhesive region 16X) without gaps, enabling continuous bonding of multiple battery cells 1.

[0039] The side adhesive portions 17 in Figures 13C and 14 are provided on both sides of each cell support portion 20, 20E1 to 20E6. In Figures 13C and 14, multiple battery cells 1 are arranged adjacent to each other in a staggered pattern, and the dead space between adjacent battery cells 1 can be effectively utilized to expand the adhesive area 16. The battery holder 10 in Figures 13C and 14 each has three cell support portions 20 that support each battery cell 1. Three cell support portions 20 (20E1, 20E3, 20E5) that support one battery cell 1 are arranged alternately around them, and six cell support portions 20 (20E2, 20E4, 20E6) that support six adjacent battery cells 1 are arranged alternately, with six side adhesive portions 17 provided between each cell support portion 20 (20E1 to 20E6) and arranged radially from the cell bottom surface 2. The battery holder 10 described above allows the adhesive 30 to easily enter each side adhesive area 16Y from the bottom adhesive area 16X, and the adhesive 30 can be supplied to the adhesive area 16 without any gaps. (Cell support part 20)

[0040] The cell support portion 20 abuts against and supports the cell bottom surface 2, which is one of the cell end faces 1b of the battery cell 1, preventing it from sinking into the uncured adhesive 30. The cell support portion 20 abuts against the cell bottom surface 2 and determines the height, position, and orientation of the battery cell 1. It also forms an adhesive area 16 below the cell bottom surface 2, acting as a spacer and lifting spacer. In the battery holder 10 shown in Figures 4 to 8, the cell support portion 20 is provided in the holder opening window 15 of the holder bottom surface 14, and the uncured adhesive 30 is applied, supplied, and placed in the adhesive area 16 of the holder opening window 15, and each battery cell 1 is bonded and fixed with the cured adhesive 30.

[0041] The cell support portion 20 has a contact portion 21 that abuts against the cell bottom surface 2. The contact portion 21 can be, for example, a flat surface, a curved surface, a straight line, a curve, a bend, an annular shape, an arc shape, a radial shape, a spiral shape, a wave shape, etc., and can be a three-dimensional shape such as a plate shape, a hemispherical shape, a sphere shape, a cylindrical shape, a columnar shape, a trapezoidal cone, a cone shape, or a rectangular parallelepiped. One or more of these can be combined and connected, and can abut against the cell bottom surface 2 point by point, line by line, or surface by surface. The contact area of ​​the cell support portion 20 can be constant or variable. For example, the contact area can be increased by changing the shape of the contact portion 21, such as a hemisphere (Figures 11 to 13) or a cone shape, and the contact area can also be increased by the elastic deformation of an elastic part. The cell support portion 20 can be connected to the battery holder 10 to form an integrated structure, and can be made of the same or different material as the battery holder 10.

[0042] The cell support portion 20 may have one or more contact portions 21. The multiple contact portions 21 may have the same or different widths, lengths, shapes, and contact areas, and may be arranged at the same or different intervals, extension directions, orientations, and angles, and may have symmetrical or asymmetrical shapes and arrangements. For example, in Figure 10, one contact portion 21 is annular, in Figure 9, five contact portions 21 are arc-shaped, and in Figure 11, three contact portions 21 are hemispherical. In the cell support portion 20 of Figure 9, the five contact portions 21 are spaced equally apart. The multiple contact portions 21 can maintain the height, position, and horizontal orientation of the battery cell 1 while reducing the contact area of ​​each contact portion 21 with the cell bottom surface 2 and widening the adhesive area 16.

[0043] The contact portion 21 has an area, shape, width, number, and the like that allow the battery cell 1 to be supported in a predetermined position and posture. The contact portion 21 in FIGS. 7 to 9 is disposed in the holder opening window 15 and abuts against the cell bottom surface 2. The contact portion 21 in FIG. 8 is disposed at a position where it abuts against the peripheral edge portion 2a of the cell bottom surface 2 of the battery cell 1. Swelling of the battery cell 1 due to aged use is larger at the central portion of the cell bottom surface 2, and the contact portion 21 that abuts against the peripheral edge portion 2a of the cell bottom surface 2 can reduce this influence. The contact portion 21 in FIGS. 8 and 9 is disposed spaced apart from the outer peripheral portion 15a of the holder opening window 15. Note that the contact portion 21 can also be provided by being directly connected to the outer peripheral portion 15a without being bridged and connected by the non-contact portion 22. The arc-shaped contact portion 21 and the annular contact portion 21 in FIG. 9 are arranged parallel to the outer peripheral portion 15a. The cell support portion 20 supports the battery cell by the contact portion 21 partially abutting against the cell bottom surface 2. The contact area of the contact portion 21 can be, for example, 1% or more and 30% or less, 1% or more and 20% or less, or 1% or more and 15% or less of the area of the cell bottom surface 2. This is because if the contact area of the contact portion 21 is too large, the adhesion area with the cell bottom surface 2 will decrease, and if it is too small, the pressure will increase, which may damage the cell bottom surface 2 due to the contact.

[0044] The cell support portion 20 may include a non-contact portion 22 that is connected to the contact portion 21 and does not contact the cell bottom surface 2 of the battery cell 1. The non-contact portion 22 in FIGS. 8, 9, etc. connects the contact portion 21 to the battery holder 10. The non-contact portion 22 can have its tip end side and / or inner side connected to the contact portion 21, and its rear end root side and / or outer side connected to the outer peripheral portion 15a of the holder opening window 15. The non-contact portion 22 can be, for example, linear, curved, planar, curved, annular, arc-shaped, radial, spiral, wavy, etc., and can also be U-shaped, U-shaped, V-shaped, L-shaped, M-shaped, W-shaped, T-shaped, Y-shaped, etc. Further, it can be formed into plates with the same or different thicknesses and widths, can be columnar, rod-shaped, three-dimensional, can be provided with openings, notches, etc., can be cantilevered or double-supported, and can have a free end. Any two or more of these can be combined and connected.

[0045] One or more non-contact portions 22 can be provided. Multiple non-contact portions 22 can have the same or different widths, lengths, shapes, and configurations, and can be arranged at the same or different intervals, extension directions, orientations, and angles, and can have symmetrical or asymmetrical shapes and arrangements. The number of non-contact portions 22 can be the same as or different from the number of contact portions 21. For example, in Figure 11, one non-contact portion 22 is annular, in Figures 10 and 12, three non-contact portions 22 are plate-shaped, and in Figure 9, five non-contact portions 22 are roughly U-shaped with support openings 23. In Figure 9, five non-contact portions 22 are arranged at equal intervals for each contact portion 21. The non-contact portions 22 can expand the adhesive area and adhesive region 16 of the cell support portion 20 connected to and integrated with the battery holder 10, both in planar and three-dimensionally. The three or more non-contact portions 22 can be arranged within a range that overlaps with each vertex of a regular polygon inscribed in the outer peripheral portion 15a of the holder opening window 15.

[0046] The cell support portion 20 is connected to the battery holder 10 and can be integrated with the battery holder 10. The cell support portion 20 can be connected to the outer periphery 15a of the holder opening window 15 of the battery holder 10, and / or to the cylindrical side surface 12a that forms the insertion cylinder 12 of the battery holder 10, or / or the holder bottom surface 14. The cell support portion 20 can be extended and positioned inward from the outer periphery 15a of the holder opening window 15 toward the center of the cell bottom surface 2 of the battery cell 1. In Figures 8 and 9, the cell support portion 20 has a non-contact portion 22 connected to the battery holder 10, bridging and connecting the contact portion 21 and the outer periphery 15a. The contact portion 21 is positioned on the tip side (center side) of the non-contact portion 22 and is positioned at a distance from the outer periphery 15a of the holder opening window 15. Figure 9 shows that the contact portion 21 is positioned closer to the center than the outer peripheral portion 15a, and adhesive 30 can be applied around the contact portion 21, including the inside (center side) and outside (outer peripheral portion 15a side), to bond it. Furthermore, the cell support portion 20 can be made more elastically deformable by positioning the contact portion 21 on the center side (inside) of the holder opening window 15 and connecting it with a cantilevered non-contact portion 22.

[0047] The cell support part 20 can have the non-abutting part 22 and the abutting part 21 formed into an integrated structure, is provided with portions differing in height and thickness and has unevenness, and can use the upper surface facing the cell bottom surface 2 as the abutting part 21. The abutting part 21 and the non-abutting part 22 are arranged to face the cell bottom surface 2 with a height difference therebetween. The abutting part 21 abuts against the cell bottom surface 2, while the non-abutting part 22 does not abut against the cell bottom surface 2, and the adhesive 30 is arranged with the gap formed between the non-abutting part 22 and the cell bottom surface 2 serving as the adhesive region 16. The non-abutting part 22 is embedded in the adhesive 30, so that the adhesive area can be expanded planarly and three-dimensionally. The adhesive area can be expanded by extending, enlarging, widening the non-abutting part 22 and increasing the thickness thereof, and thus the support strength and reaction force of the cell support part 20 can be increased.

[0048] The cell support part 20 can have an elastically deformable elastic part. Due to the elasticity of the cell support part 20, the elastic part deforms elastically, so that the battery cell 1 can be supported at a predetermined position, height and posture, the abutment, support strength, position and area can be determined and adjusted, and tolerances can also be absorbed. The elastic part deforms elastically in the vertical direction, so that the battery holder 10 can clamp and hold the battery cell 1 up and down without gaps with strength within an appropriate range. The elastic part is elastically deformed in whole or in part of the cell support part 20 depending on its material (type and composition of resin, etc.), shape, etc., and the degree and direction of elastic deformation can be determined by the material, shape, size, thickness, length, arrangement, relative position, abutment area and the like of the abutting part 21 and / or the non-abutting part 22. For example, the elastic part can be made of hard resin to increase the reaction force and reduce the degree of elastic deformation, or can be made of soft resin to reduce the reaction force and increase the degree of elastic deformation. In addition, the reaction force can be increased by widening the width, shortening the length and increasing the thickness, and the reaction force can be reduced by narrowing the width, lengthening the length and reducing the thickness. The cell support part 20 and the elastic part can be arranged at the same height for support, and the cell support part 20 and the elastic part can also be arranged at different heights to increase the reaction force stepwise.

[0049] When the first and second split holders 11A and 11B are connected to form the battery holder 10, the battery cell 1 is sandwiched between the first and second split holders 11A and 11B, with the battery cell 1 being housed in the insertion tube 12 of the first split holder 11A and the insertion tube 12 of the second split holder 11B, respectively. The total length of the insertion tube 12 of the battery holder 10, which is the sum of the insertion tube 12 of the first split holder 11A and the insertion tube 12 of the second split holder 11B, is set to be slightly shorter than the axial length of the battery cell 1. When the first and second split holders 11A and 11B are connected, one of the pair of cell end faces 1a and 1b of the battery cell 1 abuts against the inner end 12b of the insertion tube 12 of the first split holder 11A, and the other of the pair of cell end faces 1a and 1b of the battery cell 1 abuts against the inner end 12b of the insertion tube 12 of the second split holder 11B. Figure 8 shows that the cell end face 1a of the battery cell 1 abuts against the inner end 12b of the insertion tube 12 of the first split holder 11A, and the cell end face 1b (cell bottom face 2) abuts against the inner end 12b of the insertion tube 12 of the second split holder 11B. A cell support portion 20 is provided at the inner end 12b of the insertion cylinder 12 of the second split holder 11B, and the contact portion 21 of the cell support portion 20 abuts against the cell end face 1b (cell bottom face 2). Since the cell support portion 20 has an elastic portion, it can absorb variations in the axial length of the battery cell 1, and connect the first split holder 11A and the second split holder 11B while supporting both sides of the pair of cell end faces 1a and 1b of the battery cell 1 without rattling.

[0050] The reaction force of the elastic part is set to be greater than or equal to the weight of the cell and the pressure applied by the holding jig, allowing elastic deformation to occur with the battery cell 1 in place. The reaction force is set to a range that prevents gaps or openings from occurring between the divided holders 11 when the battery holder 10 is connected, fitted, and closed, and that does not cause damage to the battery cell 1. Furthermore, even if the battery cell 1 swells due to prolonged use, it is set to a range that does not cause damage or breakage to the adhesive 30, battery holder 10, lead plate 5, etc. By setting the elastic reaction force within an appropriate range, the battery holder 10 can hold the battery cell 1 in a predetermined position and orientation, preventing openings between the divided holders 11 and damage to the battery cell 1. The range of elastic deformation, contact, and interference is set to a range that prevents gaps from occurring between the top of the battery cell 1 and the battery holder 10, at the maximum tolerance obtained by adding the tolerances of the battery cell 1, battery holder 10, and other components and assembly.

[0051] The cell support section 20A in Figures 9A to 9C has 5 contact portions 21A and 5 non-contact portions 22A that connect the contact portions 21A to the outer periphery 15a of the holder opening window 15. The 5 arc-shaped contact portions 21A are spaced apart, and each contact portion 21A is parallel (including substantially parallel) along the outer periphery 15a of the holder opening window 15 and connected to the inside of the non-contact portion 22A. The non-contact portions 22A are connected to both ends of the contact portions 21A and consist of pairs that connect the contact portions 21A to the outer periphery 15a. The contact portions 21A and the pair of non-contact portions 22A form a substantially U-shape surrounding the support opening 23. The pair of non-contact portions 22 of the cell support section 20A can be made narrower and more elastically deformable compared to the single plate-shaped non-contact portion 22. The cell support portion 20B in Figures 10A to 10C has one annular contact portion 21B and three non-contact portions 22B that connect the contact portion 21B to the outer periphery 15a. The contact portion 21B is arranged parallel (including substantially parallel) to the outer periphery 15a, spaced apart from the holder opening window 15, and the three non-contact portions 22B are arranged at equal intervals, connecting the contact portion 21B to the outer periphery 15a on three sides. The contact portion 21B is connected to the inside of the non-contact portion 22B, and the three non-contact portions 22B are spaced apart, connecting the annular contact portion 21B and the outer periphery 15a in a double-support manner on three sides.

[0052] The cell support portion 20C in Figures 11A to 11C has three hemispherical, embossed, and convex contact portions 21C and one annular non-contact portion 22C that connects the contact portion 21C to the outer periphery 15a. The annular non-contact portion 22C is a flat, ring-shaped plate connected to the outer periphery 15a, and three contact portions 21 are provided on the upper surface of the non-contact portion 22C, spaced apart from the outer periphery 15a. The cell support portion 20D in Figures 12A to 12C has three contact portions 21D and three non-contact portions 22D connected to each contact portion 21D. The contact portions 21D are hemispherical, embossed, and convex, similar to Figures 11A to 11C, and the non-contact portions 22D are flat plates, provided at equal intervals for each contact portion 21D, and connect the contact portions 21B to the outer periphery 15a.

[0053] The height and thickness (H1) of the contact portion 21 can be, for example, 0.1 mm or more and 1 cm or less, preferably 0.2 mm or more and 5 mm or less, and more preferably 0.3 mm or more and 3 mm or less. The thickness (H2) of the non-contact portion 22 can be, for example, 0.1 mm or more and 5 mm or less, preferably 0.2 mm or more and 4 mm or less, and more preferably 0.3 mm or more and 3 mm or less. The height difference (H1-H2) between the contact portion 21 and the non-contact portion 22 can be, for example, 0.1 mm or more and 5 mm or less, preferably 0.2 mm or more and 4 mm or less, and more preferably 0.2 mm or more and 3 mm or less. The bonding area 16 can be expanded by increasing the height (H1) of the contact portion 21, decreasing the thickness (H2) of the non-contact portion 22, and increasing the height difference between the contact portion 21 and the non-contact portion 22, but if the height of the contact portion 21 is too high, it will become larger. Furthermore, if the height of the contact portion 21 is too low and the thickness of the non-contact portion 22 is too thin, the support strength of the battery cell 1 may become insufficient. The contact portion 21 can be connected to the upper surface and / or vertical surface of the non-contact portion 22, and for example, ribs can be erected on the non-contact portion 22, and convex portions, protrusions, and embossings can be provided, and it can also be connected to the tip, end face, and side surface of the non-contact portion 22. (Adhesive 30)

[0054] The adhesive 30 detachably bonds the battery cell 1 to the battery holder 10. Any adhesive 30 that detachably bonds each battery cell 1 can be used; for example, urethane, silicone-based adhesives can be used. A two-component room-temperature curing agent can be used. The shear strength of the adhesive 30 can be, for example, 1 MPa to 3 MPa. The uncured adhesive 30 applied, placed, and supplied to the bonding area 16 hardens to bond and fix the battery cell 1 to the battery holder 10. The adhesive strength is set within an appropriate range for detachable battery cells 1 by adjusting one or more of the material, properties, adhesive strength, bonding area, quantity, and peel strength of the bonding interface of the adhesive 30. By increasing the bonding area 16 and bonding surface area of ​​the adhesive 30, the adhesive strength can be improved, allowing for stable bonding of the battery cell 1 without misalignment, while simultaneously making it easy to detach the battery cell 1 by twisting or turning, thus achieving stable detachability. Furthermore, because the battery holder 10 has a side adhesive portion 17, the adhesive area 16 expands to a side adhesive area 16Y that communicates with the bottom adhesive area 16X, allowing the adhesive 30 to continuously embrace the cell bottom surface 2 and the cell side surface 1c, enabling three-dimensional bonding across multiple surfaces.

[0055] Furthermore, the battery pack 100 is provided with a holder opening window 15 on the holder bottom surface 14, and the holder opening window 15 communicates with the bonding area 16, allowing the battery pack to be bonded to the cell bottom surface 2 with adhesive 30, thus facilitating the application and placement of the adhesive 30. As illustrated in Figure 15, the adhesive 30 can be applied to and placed on the inner surface of the outer case 50 (second divided case 51B) and / or on the heat dissipation part 40 (outer case 50, etc.), such as a heat sink, which is placed on the inner surface of the outer case 50. By bringing the holder bottom surface 14 of the battery holder 10 into contact with and pressing it against the outer case 50, etc., to which the adhesive 30 has been applied, the adhesive 30 can be supplied and placed in the bonding area 16 from the holder opening window 15, and the adhesive 30 can bond the battery cell 1 and the battery holder 10, as well as to the outer case 50 and / or the heat sink. In this process, the cell support portion 20 prevents sinking into the uncured adhesive 30, allowing the battery cell 1 to be supported in a predetermined position, height, and orientation, and enabling the adhesive 30 to harden, bond, and fix the cell in place.

[0056] As shown in Figure 15, the adhesive 30 can be easily applied and placed in a continuous manner, such as in a single stroke or in a linear pattern, at predetermined locations on the outer casing 50 or the like. By placing the adhesive 30 continuously, it is not necessary to apply the adhesive 30 to each battery cell 1 and insertion tube 12, making the application and placement of the adhesive 30 easy and time-saving, shortening the process time, and allowing for easy confirmation of the amount and placement range of the adhesive 30, thereby improving the efficiency and cost of manufacturing and assembly. The continuously placed adhesive 30 can continuously connect the cell bottom surfaces 2 of multiple battery cells 1 to the battery holder 10. The adhesive 30 placed in a single stroke can bond each adjacent battery cell 1 to the battery holder 10, and can also bond each battery cell 1 to the outer casing 50 or the like. In the battery pack 100, the battery holder 10 has a holder opening window 15, allowing the adhesive 30 to be supplied and placed in the bonding area 16 from the holder opening window 15, and the cell support part 20 can support the battery cell 1 in a predetermined position and orientation. Furthermore, the cell support portion 20 can supply and place the adhesive 30 without gaps in the bonding area 16 without hindering the movement, supply, and filling of the adhesive 30 from the holder opening window 15. The adhesive 30 can be applied and placed on one or more of the following: the battery holder 10 side, the battery cell 1 side, or the side to which the battery cell 1 is bonded.

[0057] One or more of the outer casing 50 (first and / or second divided cases 51A, 51B), the heat dissipation section 40, and the battery holder 10 may have support parts and connecting parts that connect and fix each other. For example, the second divided case 51B in Figures 2 and 15 is provided with a plurality of protrusions 52 that project inward from its inner surface, and the protrusions 52 can be heat-welded and flattened to fix, support, and position the heat dissipation section 40. In addition, screw holes, bosses, etc., can be provided in the outer casing 50 (first and second divided cases 51A, 51B) to connect, fasten, and fix the heat dissipation section 40 and / or the battery holder 10, and an adhesive area 16 can be formed. Furthermore, the protrusions 52 can abut against the holder bottom surface 14 to support and position the battery holder 10 at a predetermined position and height, and an adhesive area 16 can be formed between the holder bottom surface 14 and the outer casing 50 or the heat dissipation section 40. The battery pack 100 in Figures 2 and 15 has a heat dissipation section 40, which has multiple through holes 41 corresponding to multiple protrusions 52. The through holes 41 allow the protrusions 52 to be inserted through the holes 41 to position the heat dissipation section 40, and the protrusions 52 inserted through the through holes 41 can extend inward beyond the heat dissipation section 40 and contact the bottom surface 14 of the holder, forming an adhesive area 16.

[0058] As shown in Figures 2 and 8, the battery pack 100 can have a heat dissipation section 40, such as a metal plate, positioned below the battery holder 10, facing the cell bottom surface 2, to dissipate and cool the heat of the battery cell 1. The adhesive 30 can bond and connect the cell bottom surface 2 of the battery cell 1 to the heat dissipation section 40, such as the metal plate. Furthermore, the heat dissipation section 40 can have a refrigerant circulation mechanism for circulating a refrigerant internally and a forced cooling mechanism for forcibly cooling the outer surface with airflow, etc., and can be connected to improve heat dissipation and cooling performance. The adhesive 30 can be directly bonded to the heat dissipation section 40 without the interposition of an insulating sheet, enabling direct and efficient heat dissipation and cooling. Between the cell bottom surface 2 of the battery cell 1 and the heat dissipation section 40, such as the metal plate, the adhesive 30 and the resin of the cell support section 20 are interposed, and insulation can be ensured without the interposition of an insulating sheet by securing a predetermined clearance. An insulating sheet can also be interposed between the adhesive 30 and the heat dissipation section 40.

[0059] The adhesive 30, as a thermally conductive adhesive 30 containing a thermally conductive filler or other thermally conductive material that improves thermal conductivity, can improve heat dissipation and cooling performance, and can further improve the contribution of the adhesive 30 to heat dissipation and cooling performance. The thermally conductive adhesive 30 has higher thermal conductivity than the adhesive 30 that does not contain a thermally conductive filler, and the thermal conductivity can be determined by the contained substance, content, ratio, etc. For example, it can be 2 times or more, 3 times or more, 5 times or more, 8 times or more, or 10 times or more than the adhesive 30 that does not contain a thermally conductive filler. The thermal conductivity of the thermally conductive adhesive 30 can be, for example, 0.3 W / mk or more, 0.5 W / mk or more, 1 W / mk or more, 2 W / mk or more, 10 W / mk or less, 8 W / mk or less, or 5 W / mk or less.

[0060] The adhesive 30 has insulating properties and can be made of, for example, a silicone-based, urethane-based, or epoxy-based resin. Preferably, the adhesive 30 has fluidity and viscosity so that it can spread, move, fill, and supply from the applied and placed position in an uncured state, and can spread in the bonding area 16 and fill gaps.

[0061] The battery pack 100 described above has adhesive 30 that is removable, and by placing and bonding the adhesive 30 to the cell bottom surface 2 side of one cell end face 1b of the battery cell 1, the battery cell 1 can be attached and detached, making it easy to remove and replace the battery cell 1. For example, with the battery pack 100, the battery holder 10 and lead plate 5 on the upper side of the battery cell 1 that are not bonded with adhesive 30 can first be removed, and one or more specific battery cells 1 that have deteriorated, have reduced characteristics or performance, or have malfunctioned can be removed by pinching, twisting, pulling, etc., and replaced with a new battery cell 1. This configuration allows for the effective use of battery cells 1 other than the specific battery cell 1, and substantially extends the lifespan of the battery pack 100.

[0062] The battery pack 100 described above has a cell support section 20 and a holder opening window 15 on the same cell bottom surface 2 side. The adhesive 30 enters the bonding area 16 from the outer case 50 and heat dissipation section 40 through the holder opening window 15, bonding the battery cell 1, battery holder 10, and heat dissipation section 40, allowing the battery cell 1 to dissipate heat and be cooled. The cell support section 20 supports the battery cell 1 in a predetermined position and orientation, preventing the battery cell 1 from sinking into the uncured adhesive 30, and improving vibration and impact resistance without creating a gap between the upper side of the battery cell 1 and the battery holder 10. This is effective against vibrations during driving and use of electrical equipment with the battery pack 100 installed or built in, and against impacts from dropping when removing the battery pack 100.

[0063] The battery pack 100 illustrated above is attached to the electrical device to be driven and supplies power to the electrical device. When the remaining capacity of the battery pack 100 becomes low or when the battery pack 100 deteriorates over time, the battery pack 100 can be replaced and the electrical device can be used continuously. However, this disclosure is not limited to a replaceable type of battery pack 100 that mainly houses battery cells 1, but can also be applied to a configuration in which the battery cells 1 are housed within the casing of the electrical device. In this disclosure, a battery pack 100 is defined as a device in which battery cells 1 are housed within a case, and also includes a device in which the battery cells 1 for driving are built into the casing of the electrical device itself.

[0064] The battery pack 100 according to this disclosure is useful as a battery pack 100 that allows for the replacement of the battery cells 1 while preventing the battery cells 1 from sinking into the uncured adhesive 30.

[0065] 100...Battery pack 1...Battery cell; 1a, 1b...Cell end face, 1c...Cell side 2...Cell bottom face; 2a...Peripheral edge 5...Lead plate 10...Battery holder 11...Divided holder; 11A...First divided holder, 11B...Second divided holder 12...Insertion tube; 12a...Tube side, 12b...Inner end 13...Holder end face 14...Holder bottom face 15...Holder opening window; 15a...Outer circumference 16...Adhesive area; 16X...Bottom adhesive area, 16Y...Side adhesive area 17...Side adhesive part 20, 20A to 20E, 20E1 to 20E6...Cell support part 21, 21A to 21E...Contact part 22, 22A to 22E, 22E1 to 22E6...Non-contact part 23...Support opening 30...Adhesive 40...Heat dissipation section 41...Through hole 50...Outer case 51...Divided case; 51A...First divided case, 51B...Second divided case 52...Protrusion

Claims

1. A battery pack comprising: a plurality of battery cells, each having a pair of cell end faces and a cell side surface connecting the cell end faces; a battery holder that holds the plurality of battery cells aligned in the direction of the cell side surfaces with the orientation of the cell end faces aligned; an adhesive that detachably adheres the battery cells to the battery holder; and a cell support portion that prevents the battery cells from sinking into the adhesive, wherein the battery holder has a holder opening window that exposes the cell end faces, the adhesive is placed in the holder opening window and adheres one of the pair of cell end faces of the battery cell to the battery holder, and the cell support portion has a contact portion that abuts against one of the pair of cell end faces of the battery cell.

2. A battery pack according to claim 1, wherein the cell support portion has an elastic portion that is elastically deformable.

3. A battery pack according to claim 1, wherein the battery holder is configured to be divided into a plurality of parts in the axial direction of the battery cell, and comprises a first divided holder and a second divided holder, the first divided holder and the second divided holder each have an insertion cylinder that opens to accommodate each of the battery cells, and in a state in which the first divided holder and the second divided holder are connected, one of the pair of cell end faces of the battery cell abuts against the inner end of the insertion cylinder of the first divided holder or the second divided holder, and the other of the pair of cell end faces of the battery cell abuts against the abutting portion.

4. A battery pack according to claim 1, wherein the contact portion is disposed at a distance from the outer periphery of the holder opening window.

5. A battery pack according to claim 1, wherein the cell support portion is connected to the contact portion and has a non-contact portion that does not contact one of the pair of cell end faces of the battery cell, and the non-contact portion is connected to the battery holder.

6. A battery pack according to claim 1, wherein the cell support portion has a plurality of contact portions that are spaced apart from each other.

7. A battery pack according to claim 1, wherein the contact portion contacts one peripheral edge of the pair of cell end faces of the battery cell.

8. A battery pack according to claim 1, wherein the adhesive is a thermally conductive adhesive containing a thermally conductive filler.

9. A battery pack according to claim 1, wherein the adhesive for bonding a plurality of adjacent battery cells to the battery holder is arranged in a continuous manner.

10. A battery pack according to claim 1, wherein the battery holder has a side bonding portion that forms an adhesive region on one of the pair of cell end faces of the battery cell, where the adhesive can be present to be bonded to the side surface of the cell.

11. A battery pack according to any one of claims 1 to 10, further comprising a heat dissipation section for cooling the battery cells, wherein the heat dissipation section is bonded to the battery cells with the adhesive.

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