Power supply unit and method for manufacturing the same

Abstract

This power source device comprises: a plurality of battery blocks in which a plurality of holder through holes are formed; a plurality of shaft parts respectively inserted in the holder through holes in a state in which the plurality of battery blocks are connected in a connecting direction in an orientation in which the holder through holes are aligned; a cylindrical exterior case that is open at both ends and that houses the battery blocks; a first lid that closes a first open end of the exterior case; and a second lid that closes a second open end of the exterior case. Each of the plurality of shaft parts has a screw thread formed at least at the tip, and the first lid is configured to be secured by the screw thread formed at the tip of each shaft part in a state in which the plurality of shaft parts are inserted through a core block that connects the plurality of battery blocks.

Description

Technical Field

[0001] The present disclosure relates to a power supply device including a plurality of battery cells and a method for manufacturing the same.

Background Art

[0002] Power supply devices in which a plurality of battery cells are connected in series or parallel are used as drive power sources for moving bodies such as assist bicycles, electric carts, and electric scooters, or for electric tools and vacuum cleaners. Many power supply devices of this type have a configuration in which a plurality of battery blocks in which a plurality of battery cells are connected in series or parallel are further connected (Patent Document 1).

[0003] As a configuration for connecting such a plurality of battery blocks, there is a method of fixing a core block by fastening a shaft and a nut. However, this method has a problem in that it requires work to attach the shaft to the nut, which is time-consuming.

[0004] As another method, a method of directly fixing the battery blocks to each other with screws can also be considered. However, this method also has a problem in that the man-hours increase according to the number of battery blocks.

Prior Art Documents

Patent Documents

[0005]

Patent Document 1

Summary of the Invention

[0006] One object of the present disclosure is to provide a power supply device and a method for manufacturing the same in which connection of battery blocks and fixing to an exterior case can be easily performed.

[0007] To achieve the above objective, a power supply device according to one embodiment of the present disclosure comprises a plurality of battery blocks, each having a plurality of battery cells connected in series or parallel, and each having a plurality of holder through-holes; a plurality of shaft portions inserted through each of the plurality of holder through-holes, with the plurality of battery blocks connected in the connection direction in a position where the plurality of holder through-holes are centered; a cylindrical outer case for housing the plurality of battery blocks, with both ends open to form a first open end and a second open end; a first lid portion that closes the first open end of the outer case; and a second lid portion that closes the second open end of the outer case. Each of the plurality of shaft portions has a screw thread formed at least at its tip. The plurality of battery blocks are connected in the connection direction to form a core block. With the plurality of shaft portions inserted through the plurality of holder through-holes of the plurality of battery blocks in the core block, the first lid portion is fixed by the screw threads of the plurality of shaft portions.

[0008] In another method of manufacturing a power supply device, a plurality of battery blocks are prepared, each consisting of multiple battery cells connected in series or parallel. With the plurality of battery blocks connected in the connection direction in an orientation where the plurality of holder through holes opened in each of them are aligned, a plurality of shaft portions are inserted into the holder through holes, and the threads formed at least at the tip of each shaft portion are screwed into a first lid portion placed on the end face of the core block to fix it and form a core block. An outer case is prepared having both ends open to form a first open end and a second open end. The core block is inserted from one of the first open ends of the outer case. The second open end of the outer case is closed with a second lid portion.

[0009] According to one embodiment of the power supply device and its manufacturing method, the core block, which is made up of multiple battery blocks connected together, can be fixed to the first lid by a shaft that penetrates the core block. This eliminates the need to individually fix each battery block and provides the advantage of stably fixing the core block housed in the outer case. As a result, even if the power supply device is subjected to external forces such as dropping or vibration, the core block remains stably fixed within the outer case, which helps to prevent breakage or damage to internal components. [Brief explanation of the drawing]

[0010] [Figure 1] Figure 1 is an external perspective view of a power supply device according to Embodiment 1 of this disclosure. [Figure 2] Figure 2 is an exploded perspective view of the power supply unit shown in Figure 1. [Figure 3] Figure 3 is an exploded perspective view of the power supply unit shown in Figure 2, viewed from the rear. [Figure 4] Figure 4 is an exploded perspective view of the core block shown in Figure 2. [Figure 5] Figure 5 is an exploded perspective view of the core block shown in Figure 4. [Figure 6] Figure 6 is an exploded perspective view of the battery block shown in Figure 5. [Figure 7] Figure 7 is a vertical cross-sectional view of the power supply unit in Figure 1 along line VII-VII. [Figure 8] Figure 8 is a schematic horizontal cross-sectional view of a power supply device according to Embodiment 1 of this disclosure. [Figure 9] Figure 9 is a horizontal cross-sectional view of the power supply unit in Figure 1 along the IX-IX line. [Figure 10] Figure 10 is a horizontal cross-sectional view of the main part of the power supply unit shown in Figure 1 along line XX, with an enlarged cross-sectional view. [Figure 11] Figure 11 is a perspective view of the first packing shown in Figure 4, with an enlarged cross-sectional view of the main part. [Figure 12] Figure 12 is a front view of the second packing shown in Figure 3. [Figure 13] Figure 13 is a schematic horizontal cross-sectional view of a power supply device according to Embodiment 2 of this disclosure. [Modes for carrying out the invention]

[0011] Embodiments of this disclosure may be specified by the following configurations and features.

[0012] In other embodiments of the present disclosure, the power supply device, in any of the above embodiments, has an insert nut embedded in the first lid portion, which engages with the threads formed at the tip of each shaft portion, with the multiple shaft portions inserted through the core block connecting the multiple battery blocks. With this configuration, even long shaft portions can be securely connected to the first lid portion by the insert nut, and the connection of the battery blocks is stabilized.

[0013] Other embodiments of the present disclosure include, in any of the above embodiments, a plurality of first screw portions for fixing the first lid to the first open end of the outer casing, with the core block, to which the first lid is fixed by the shaft portion, inserted from the first open end of the outer casing, and the outer casing is provided with first screw holes at the edge of the first open end for screwing the first screw portions. The above configuration provides the advantage that the core block can be securely fixed to the outer casing via the first lid.

[0014] Other embodiments of the power supply device according to the present disclosure further include a first packing interposed at the interface between the first lid and the outer case, wherein the first packing is located on the inner surface side of the outer case, relative to the first screw hole, when viewed from the first opening end. With this configuration, while the first lid is fixed to the outer case by the first screw, the first packing can be tightly fitted at the interface between the first lid and the outer case to ensure waterproofing of the inside of the outer case.

[0015] In another aspect of the power supply device according to the present disclosure, in any of the above aspects, the first screw portion is located outside the shaft portion when viewed from the end face of the exterior case. With the above configuration, while fixing the core block in the exterior case with the shaft portion, the first opening end of the exterior case can be closed via the first packing with the first screw portion, thereby achieving waterproofing.

[0016] In another aspect of the power supply device according to the present disclosure, in any of the above aspects, further, with the core block to which the first lid portion is fixed by the shaft portion inserted from the first opening end of the exterior case, the second lid portion is fixed to the second opening end of the exterior case in a state of pressing the core block, and includes a plurality of second screw portions, and the exterior case is provided with second screw holes for screwing the second screw portions at the edge of the second opening end. With the above configuration, with the core block fixed to the first lid portion, the second lid portion can be fixed after being inserted into the exterior case, so that the advantage of efficiently performing the assembly process can be obtained.

[0017] In another aspect of the power supply device according to the present disclosure, in any of the above aspects, further, a second packing interposed at the interface between the second lid portion and the exterior case is provided, and the second packing is located on the inner surface side of the exterior case rather than the second screw hole when viewed from the second opening end. With the above configuration, with the second lid portion fixed to the exterior case with the second screw portion, the second packing can be brought into close contact at the interface between the second lid portion and the exterior case to achieve waterproofing inside the exterior case.

[0018] In another aspect of the power supply device according to the present disclosure, in any of the above aspects, the second packing forms a protruding portion that protrudes toward the interface with the exterior case along the connection direction of the battery blocks. With the above configuration, when the second lid portion is fixed to the exterior case with the second screw portion, the protruding portion can be elastically deformed to fill the gap.

[0019] In other embodiments of the present disclosure, the power supply device is configured such that, in any of the above embodiments, the second screw portion is located outside the shaft portion when viewed from the end face of the outer casing. With this configuration, the core block inside the outer casing is fixed by the shaft portion, while the second screw portion closes the second open end of the outer casing via the second packing, thereby ensuring waterproofing.

[0020] Other embodiments of the present disclosure further include, in any of the above embodiments, a substrate holder disposed on one end face of a core block connecting the plurality of battery blocks, the end face facing the second lid, and a circuit board held by the substrate holder, wherein the substrate holder has a holder insertion hole through which the shaft portion is inserted, and the shaft portion is inserted through the holder insertion hole of the substrate holder with the screw head side facing the substrate holder. That is, each of the plurality of shaft portions has a screw head provided on the opposite side of the screw threads, and the distance between the substrate holder and the screw head is shorter than the distance between the substrate holder and the screw threads.

[0021] Other embodiments of the present disclosure further include, in any of the above embodiments, one or more lateral elastic bodies that are positioned between any side surface of the core block and the inner surface of the outer casing, and extend in the direction of connection of the battery block. This configuration prevents the core block from colliding with the inner wall of the outer casing and being damaged inside the outer casing when the power supply is subjected to an impact from the side.

[0022] In other embodiments of the present disclosure, the power supply device, in any of the above embodiments, has a narrowed portion formed in which the side elastic body is narrowed along the connection direction of the battery block. This configuration has the advantage that the process of press-fitting the core block into the outer casing can be made easier by partially reducing the pressure at the narrowed portion.

[0023] Embodiments of this disclosure will be described below with reference to the drawings. However, the embodiments shown below are illustrative examples for embodying the technical concept of the present invention, and the present invention is not limited to these. 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 the present invention to those, unless otherwise specifically stated, 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 material, with one material serving multiple elements, or conversely, the function of one material may be shared among multiple materials.

[0024] The power supply device disclosed herein increases voltage and capacity by connecting a large number of battery cells in series or parallel, and can be suitably used as a power source for mobile devices such as electric assist bicycles, electric bicycles, electric motorcycles, electric wheelchairs, electric tricycles, and electric carts. The power supply device can also be used as a power source for various electrical equipment used indoors and outdoors, such as electric cleaners and power tools. Furthermore, the power supply device can be used in a variety of applications, such as a backup power source for servers, a power source mounted on electric vehicles such as hybrid cars and electric vehicles to supply power to the drive motor, a power source for storing electricity generated from natural energy sources such as solar power and wind power, a power source for storing off-peak electricity, and a power storage power source for leveling the power load during peak power demand. Below, an example of a power supply device according to one embodiment of the disclosure, used as a battery pack for an electric assist bicycle, will be described.

[0025] [Embodiment 1] A power supply device 1000 according to Embodiment 1 of this disclosure is shown in Figures 1 to 12. In these figures, Figure 1 is an external perspective view of the power supply unit 1000 according to Embodiment 1 of the present disclosure, Figure 2 is an exploded perspective view of the power supply unit 1000 of Figure 1, Figure 3 is an exploded perspective view of the power supply unit 1000 of Figure 2 viewed from the rear, Figure 4 is an exploded perspective view of the core block 100 of Figure 2, Figure 5 is an exploded perspective view of the core block 100 of Figure 4, Figure 6 is an exploded perspective view of the battery block 10 of Figure 5, Figure 7 is a vertical cross-sectional view of the power supply unit 1000 of Figure 1 along line VII-VII, Figure 8 is a schematic horizontal cross-sectional view of the power supply unit 1000 according to Embodiment 1 of the present disclosure, Figure 9 is a horizontal cross-sectional view of the power supply unit 1000 of Figure 1 along line IX-IX, Figure 10 is a horizontal cross-sectional view of the power supply unit 1000 of Figure 1 with an enlarged cross-sectional view of the main part along line XX, Figure 11 is a perspective view of the first packing 60 of Figure 4 with an enlarged cross-sectional view of the main part, and Figure 12 is an enlarged plan view of the second packing 70 of Figure 3. The power supply unit 1000 shown in these figures comprises a core block 100, an outer case 20, a first cover 30, and a second cover 40.

[0026] As shown in Figure 1, the outer casing 20 has an external appearance that is rod-shaped with its exterior extended in one direction. Inside the outer casing 20 is a cylindrical housing with both ends open, into which the core block 100 is inserted, as shown in Figures 2 and 3. Of the open ends of the outer casing 20, the first open end 21 is closed by the first lid 30. The second open end 22, opposite the first open end 21, is closed by the second lid 40.

[0027] As shown in Figures 2 to 5, the core block 100 is constructed by connecting a plurality of battery blocks 10 in the connection direction Dc. The plurality of battery blocks 10 are stacked and connected by a shaft portion 50. As shown in Figures 6 to 7, each battery block 10 is equipped with a battery holder 11 that holds a plurality of battery cells 1. The battery holder 11 positions the plurality of battery cells 1 in fixed positions. The plurality of battery cells 1 held by each battery block 10 are connected in series or in parallel.

[0028] Each battery block 10 also has multiple holder through-holes 12. As shown in Figure 4, the multiple battery blocks 10 are connected in one direction in a position where each holder through-hole 12 is centered, and a shaft portion 50 is inserted through each of the connected holder through-holes 12. Each of the multiple shaft portions 50 has a screw thread 51 at least at its tip.

[0029] The first lid portion 30 is fixed to the core block 100 by screw threads 51 formed at the tip of each shaft portion 50, with the shaft portions 50 inserted through the core block 100. With this configuration, as shown in Figure 8, the core block 100, which is made up of multiple battery blocks 10 connected together, can be fixed to the first lid portion 30 by the shaft portions 50 that pass through it, thus eliminating the need to fix each battery block 10 individually, and providing the advantage of stably fixing the core block 100 housed in the outer case 20. As a result, even if the power supply unit 1000 is subjected to external forces such as dropping or vibration, the core block 100 is stably fixed in the outer case 20, which helps to prevent breakage or damage to internal components.

[0030] Conventionally, methods for securing the core block housed within the outer casing have included fastening methods using E-rings or push nuts. However, these methods have the problem of being complex to manufacture. Another method involves drilling pilot holes in the outer casing and securing the battery block from the outside with screws. However, this method also has problems such as requiring many processing steps and the need for additional waterproofing. Furthermore, a method of securing the core block by fastening a shaft to a nut is also conceivable. However, this method requires the work of attaching the shaft to the nut, which is time-consuming. In contrast, in the power supply device 1000 according to this embodiment, as described above, the shaft portion 50 that penetrates the battery block 10 connects it to the first lid portion 30, and the core block 100 to which this first lid portion 30 is secured is inserted into the outer casing 20, thereby achieving a firm fixation with the first lid portion 30 which has a large surface area. The following describes each component in detail.

[0031] (Outer case 20) As shown in Figures 1 to 3, the outer casing 20 is formed in a cylindrical shape with openings at both ends, and comprises a first lid portion 30 that closes the first open end 21 and a second lid portion 40 that closes the second open end 22 of the outer casing 20. As shown in Figure 3, the outer casing 20 is inserted into the core block 100 with the first lid portion 30 fixed to it, and the first lid portion 30 is fixed to the outer casing 20 with the first screw portion 31. Then, as shown in Figure 2, the second lid portion 40 is fixed to the outer casing 20 with the second screw portion 41.

[0032] The outer casing 20 is formed into a roughly rectangular tube shape with an approximately rectangular cross-section and open ends. Furthermore, the four corners of the rectangular tube outer casing 20 are beveled to create curved surfaces. This shape of outer casing 20, with its curved corners, achieves both a beautiful appearance and a pleasant tactile feel.

[0033] The first lid portion 30 and the second lid portion 40 are formed in a cross-sectional view to conform to the outer shape of the outer case 20 so that the first open end 21 and the second open end 22 of the outer case 20 can be closed with a good appearance. Furthermore, the first lid portion 30 and the second lid portion 40 are equipped with a first stepped wall 32 and a second stepped wall 42 that are inserted into the first open end 21 and the second open end 22 of the outer case 20. With the first stepped wall 32 and the second stepped wall 42 inserted inside the first open end 21 and the second open end 22 of the outer case 20, the first stepped wall 32 and the second stepped wall 42 are brought into contact with the inner surfaces of the first open end 21 and the second open end 22 of the outer case 20, thereby closing these first open end 21 and the second open end 22. In other words, the first lid 30 and the second lid 40 have outer shapes of the first stepped wall 32 and the second stepped wall 42 that are slightly smaller than the inner shape of the outer case 20, and the outer shapes of the first stepped wall 32 and the second stepped wall 42 are approximately equal to, or slightly larger than, the outer shape of the outer case 20. These first lid 30 and the second lid 40 close by bringing the contact surfaces formed on the outside of the first stepped wall 32 and the second stepped wall 42 into contact with the first open end 21 and the second open end 22 of the outer case 20. The outer case 20 can be connected to the first lid 30 and the second lid 40 while positioning them by providing the first stepped wall 32 and the second stepped wall 42 on the first lid 30 and the second lid 40.

[0034] Furthermore, the first lid portion 30 and the second lid portion 40 shown in Figures 2 and 3 have ring-shaped first packings 60 and 70 positioned on the outer circumferential surfaces of the first stepped wall 32 and the second stepped wall 42. The outer case 20 connects the first lid portion 30 and the second lid portion 40 in a sealed structure via the ring-shaped first packings 60 and 70 positioned on the outer circumferential surfaces of the first stepped wall 32 and the second stepped wall 42. As shown in Figures 9 and 10, the first packings 60 and 70 are integrally formed in a shape that is continuously bent from the first open end 21 and the second open end 22 to their inner surfaces. The first packing 60 and the second packing 70, having this shape, are continuously interposed at the interface between the first lid portion 30 and the second lid portion 40 and the first open end 21 and the second open end 22, and at the interface between the outer circumferential surfaces of the first stepped wall 32 and the second stepped wall 42 and the outer circumferential surfaces of the first open end 21 and the second open end 22. They are pressed and elastically compressed at these interfaces, maintaining a watertight state. As a result, a stable sealing effect is obtained.

[0035] Furthermore, the second cover 40 can be provided with a discharge connector for discharging the built-in battery cell 1 and a charging connector for charging the built-in battery cell 1. In addition, the first cover 30 and the second cover 40 can also be provided with a display unit on their surface to show the remaining capacity of the power supply unit 1000, etc. This display unit displays the remaining capacity of the power supply unit, etc., by the illumination status of a light source such as an LED.

[0036] (First lid part 30) The first lid portion 30 is fixed to the outer case 20 by the first threaded portion 31, as shown in Figure 10. The first lid portion 30 is fixed to the outer case 20 while it is first fixed to the core block 100 by the shaft portion 50. As shown in Figures 2 and 3, the core block 100 to which the first lid portion 30 is fixed is inserted from the first open end 21 side of the outer case 20, and the first lid portion 30 is fixed to the outer case 20 by the first threaded portion 31, as shown in Figure 10. The first open end 21 of the outer case 20 has a first threaded hole 23 into which the first threaded portion 31 is screwed. The first lid portion 30 also has a first through hole 33 through which the first threaded portion 31 is inserted. The first through hole 33 may also be a threaded hole. In this way, by fixing the first lid 30, to which the core block 100 is fixed, to the outer case 20, the core block 100 is firmly fixed to the outer case 20 via the first lid 30. Furthermore, with the first lid 30 fixed to the outer case 20, the second lid 40 is similarly fixed to the outer case 20 by the second screw portion 41, as shown in Figure 2.

[0037] The first threaded portion 31 is located outside the shaft portion 50 when viewed from the end face of the outer case 20. This arrangement allows the core block 100 inside the outer case 20 to be fixed by the shaft portion 50, while the first threaded portion 31 closes the first open end 21 of the outer case 20 via the first packing 60, thereby ensuring waterproofing.

[0038] As shown in Figure 10, the first packing 60 is positioned on the inner side of the outer case 20, relative to the first threaded portion 31, when viewed from the first open end 21. With this arrangement, while the first lid portion 30 is fixed to the outer case 20 by the first threaded portion 31, the first packing 60 can be tightly sealed at the interface between the first lid portion 30 and the outer case 20 to ensure waterproofing of the inside of the outer case 20. In other words, waterproofing at the first threaded portion 31 is unnecessary, and the interface is tightly sealed by the first packing 60, which is deformed by being pressed between the first open end 21 of the outer case 20 and the first lid portion 30, preventing water from entering the outer case 20.

[0039] Figure 11 shows a perspective view of the first packing 60. The first packing 60 is formed in an annular shape and is bent to avoid the portion of the first lid 30 where the first insertion hole 33 is provided. This allows the first packing 60 to be positioned on the inner surface side of the outer case 20 relative to the first screw portion 31. The first packing 60 also forms a first flange portion 61 that protrudes outward along the annular shape. As shown in the enlarged cross-sectional view of the main part in Figure 10, the first flange portion 61 is held between the first lid 30 and the first open end 21 and undergoes elastic deformation, thereby providing waterproofing at the interface between the first open end 21 and the first lid 30. Furthermore, the first packing 60 forms a first pleat portion 62 that is almost parallel to the first flange portion 61 and has a smaller outer circumference than the first flange portion 61. The first pleat portion 62 protrudes outward from the annular shape of the first packing 60. Multiple first pleat portions 62 are arranged in parallel. As shown in Figure 10, when the first packing 60 is press-fitted into the first opening end 21, the first pleat portion 62 protrudes to the inner surface of the outer case 20 and undergoes elastic deformation. With this structure, even if water ingress occurs beyond the first flange portion 61, as shown in Figure 10, the first packing 60 prevents moisture that seeps from the first opening end 21 to the inner surface of the outer case 20 from entering the outer case 20. In other words, it contributes to improving waterproof performance. In particular, providing a double first pleat portion 62 further improves the reliability of the waterproof performance. The number of first pleat portions 62 may be one or three or more depending on the required waterproof performance. Thermoplastic elastomers (TPE) and the like can be suitably used for such a first packing 60.

[0040] (Second lid part 40) The second lid portion 40 is fixed to the outer case 20, to which the first lid portion 30 is fixed, using the second screw portion 41. This allows the core block 100 to be fixed to the first lid portion 30, inserted into the outer case 20, and then the second lid portion 40 to be fixed, thus providing the advantage of efficient assembly. A second screw hole 24 is provided in the second open end 22 of the outer case 20 for screwing in the second screw portion 41. A second insertion hole 43 is also provided in the second lid portion 40 for inserting the second screw portion 41. The second insertion hole 43 may also be a screw hole.

[0041] The second threaded portion 41 is also located outside the shaft portion 50 when viewed from the end face of the outer case 20. This arrangement allows the core block 100 inside the outer case 20 to be fixed by the shaft portion 50, while the second threaded portion 41 closes the second open end 22 of the outer case 20 via the second packing 70, thereby ensuring waterproofing.

[0042] As shown in Figure 2, the second packing 70 is interposed between the second lid 40 and the outer case 20 to ensure waterproofing at this interface. The second packing 70 is also positioned on the inner surface of the outer case 20, relative to the second screw hole when viewed from the second opening end 22. With this arrangement, while the second lid 40 is fixed to the outer case 20 by the second screw portion 41, the second packing 70 can be tightly fitted at the interface between the second lid 40 and the outer case 20 to ensure waterproofing to the inside of the outer case 20.

[0043] The second packing 70 also has a second flange portion 71 and a second pleated portion 72, similar to the first packing 60. As shown in the enlarged cross-sectional view of the main part in Figure 10, the second packing 70 is interposed between the second lid portion 40 and the outer case 20 when the second lid portion 40 is fixed to the outer case 20 to which the first lid portion 30 is fixed with the second screw portion 41, thereby providing waterproofing at this interface.

[0044] Furthermore, as shown in Figure 12, the second packing 70 has a projection 74 that protrudes toward the interface with the outer case 20 along the connecting direction Dc of the battery block 10. With this configuration, when the second lid 40 is fixed to the outer case 20 with the second screw portion 41, the projection 74 can elastically deform and fill the gap. In particular, when the core block 100 becomes longer due to an increase in the number of battery blocks 10, tolerances accumulate and gaps are more likely to occur. Therefore, by providing the second packing 70 with a projection 74 that protrudes in the stacking direction of the battery block 10, that is, in the extension direction of the shaft portion 50, the projection 74 can be elastically deformed when the second packing 70 is clamped, suppressing the occurrence of gaps and improving the fixing strength of the core block. The second packing 70 can also be made of TPE or the like, just like the first packing 60.

[0045] (Shaft section 50) The shaft portion 50 linearly connects the multiple battery blocks 10 that constitute the core block 100. The shaft portion 50 shown in Figures 4 and 9 has a screw head 52 at its rear end and screw threads 51 at its tip, and has a total length that allows it to connect three battery blocks 10. The shaft portion 50 is preferably made of metal and has sufficient strength to fasten and connect the multiple battery blocks 10 from both sides. A metal shaft portion 50 has a large heat capacity and is characterized by its ability to effectively absorb and transfer heat even when the battery cell 1 generates heat. The shaft portion 50 described above is inserted through a holder through hole 12 provided in the battery holder 11 of each battery block 10, integrally connecting the multiple battery blocks 10 arranged linearly.

[0046] The first lid portion 30 has insert nuts 34 embedded in it that mesh with the threads 51 formed at the tip of each shaft portion 50, with multiple shaft portions 50 inserted through the core block 100. This configuration allows even long shaft portions 50 to be securely connected to the first lid portion 30 by the insert nuts 34, thus stabilizing the connection of the battery block 10. The insert nuts 34 are insert-molded into the first lid portion 30.

[0047] The shaft portion 50 only needs to have a screw thread 51 at its tip. However, the screw thread may be formed along the entire length of the shaft portion. This provides the advantage of being able to firmly connect the battery blocks together.

[0048] [Embodiment 2] In the above example, an example was described in which an insert nut 34 that meshes with the screw threads 51 formed at the tip of each shaft portion 50 is embedded in the first lid portion 30. With this configuration, even when the number of battery blocks 10 and battery cells 1 is large and the core block is long, it is possible to stably fix them to the first lid portion 30 using a long shaft portion 50. However, the present invention is not limited to this configuration, and a tapping screw may be formed at the tip of the shaft portion 50 and screwed into the first lid portion 30. In particular, when the total length of the core block is relatively short, such as when the number of battery blocks 10 is small, the length of the shaft portion 50 can be shortened to reduce the swing of the tip, so it is possible to stably fix it even with a tapping screw. Such an example is shown as a power supply device 2000 according to Embodiment 2 in the schematic horizontal cross-sectional view of Figure 13. In the power supply device shown in this figure, the same reference numerals are used for the same components as in Embodiment 1 described above, and detailed descriptions are omitted.

[0049] This power supply unit 2000 has a core block 100B composed of two battery blocks 10, and as a result, the overall length of the shaft portion 50B is shorter compared to Embodiment 1. The tip of the shaft portion 50B is a tapping screw with threads 51B that resemble wood screws. With such a short shaft portion 50B, it becomes easier to position the threads 51B at the tip onto the first cover portion 30B, and the tapping screw can be directly screwed in to secure it stably.

[0050] (Core block 100) The core block 100 is housed in an outer case 20 in a configuration where multiple battery blocks 10 are stacked axially within the outer case 20. As shown in Figures 2, 3, 4, 5, and 6, the core block 100 is constructed by stacking multiple battery blocks 10, each consisting of multiple battery cells 1 arranged in multiple rows and columns on a battery holder 11, in the longitudinal direction of the battery cells 1, and connecting them linearly. In this example, the core block 100 comprises three sets of battery blocks 10. This core block 100 increases the battery capacity [Ah] by connecting multiple battery cells 1 in parallel and increases the output voltage [V] by connecting multiple battery cells 1 in series. The power supply device disclosed herein is not limited to three sets of battery blocks 10 constituting the core block; it may be composed of two or fewer sets of battery blocks 10, or four or more sets of battery blocks 10, depending on the application and specifications.

[0051] (Battery block 10) As shown in Figure 6, each battery block 10 has a battery holder 11 with an insertion tube portion 13 for the battery cell 1, and the battery cell 1 is inserted into the insertion tube portion 13 to position the battery cell 1 in place. The battery block 10 has multiple rechargeable battery cells 1 arranged in multiple rows and columns in the battery holder 11.

[0052] Battery cell 1 is a cylindrical rechargeable secondary battery, and a lithium-ion secondary battery is preferably used. However, the present invention does not limit the battery cell to a lithium-ion battery, and other rechargeable secondary batteries such as nickel-water battery cells, nickel-cadmium batteries, and lithium polymer batteries can be used.

[0053] The battery block 10 arranges multiple battery cells 1 in a parallel orientation, with the longitudinal directions of each battery cell 1 facing the same direction. The multiple battery cells 1 constituting the battery block 10 are connected by lead plates 14 connected to the end face electrodes at both ends of the battery cells 1, so that they are connected in a desired number of parallel and series connections, and are connected to a circuit board 16 via a wiring board 15 as shown in Figure 5. The core block 100 is made up of three battery blocks 10, each containing 10 battery cells 1, and in total, 30 battery cells 1 are connected in 3 parallel and 10 series. However, the number of battery cells 1 and the connection configuration of the core block 100 can be changed as appropriate.

[0054] (Battery holder 11) The battery holder 11 is formed by molding insulating plastic into the same shape, and integrally molding the insertion cylinder portion 13 for the battery cell 1 and the connecting projection portion 17 to which the shaft portion 50 is connected.

[0055] The insertion tube portion 13 holds the battery cell 1, which is set therein, in a fixed position. In the battery holder 11 shown in the figure, the shape of the insertion tube portion 13 is such that a cylindrical battery is inserted into the insertion tube portion 13 and held in a fixed position, assuming the battery cell 1 is a cylindrical battery. However, the present invention does not necessarily limit the battery cell to a cylindrical battery; the battery cell can also be, for example, a prismatic battery. In a power supply device using a prismatic battery cell, the insertion tube portion of the battery holder is made into a rectangular tube shape.

[0056] The battery holder 11 in Figure 7 arranges 10 battery cells 1 in four vertical rows, with the batteries in each row arranged in 3, 2, 3, and 2 rows from top to bottom, so that the battery cells 1 located above and below are positioned in the gaps between the battery cells 1 located to the left and right of the adjacent battery cells 1, creating a stacked, bale-like arrangement.

[0057] As shown in Figure 6, the battery holder 11 is molded by dividing it into a pair of cell holders 11a and 11b. Each cell holder 11a and 11b that makes up the battery holder 11 is provided with an insertion cylinder portion 13 into which a battery cell 1 is inserted in a parallel position. The insertion cylinder portion 13 is open at both ends to expose the end face electrodes of the cylindrical battery inserted therein, so that a lead plate 14 can be connected to the end face electrodes. The insertion cylinder portion 13 of the cell holders 11a and 11b is long enough to insert half of the battery cell 1, and each battery cell 1 is positioned in the fixed position of the battery holder 11 by inserting half of it into one cell holder 11a and the remaining half into the other cell holder 11b.

[0058] The power supply unit 1000 also includes a substrate holder 18 and a circuit board 16 held by the substrate holder 18. The substrate holder 18 is located on one end face of the core block 100, on the end face facing the second lid 40. The substrate holder 18 has a holder insertion hole through which the shaft portion 50 is inserted. The shaft portion 50 is inserted through the holder insertion hole of the substrate holder 18, with the screw head side positioned towards the substrate holder 18. That is, the shaft portion 50 is fixed by having the screw head 52 installed on the substrate holder 18.

[0059] (Circuit board 16) Furthermore, the core block 100 includes a circuit board 16 connected to the battery block 10. As shown in Figure 5, the core block 100 has the circuit board 16 positioned on the end face of the linearly connected battery blocks 10. The circuit board 16 is positioned in place via a board holder 18. Each lead plate 14, which is connected to a plurality of battery cells 1, is connected to the circuit board 16 either directly or via a wiring board 15. The circuit board 16 has electronic components mounted on it that realize a protection circuit that controls the charging and discharging of the battery cells 1. The protection circuit also includes a circuit that detects the voltage of each battery and cuts off the charging and discharging current. Furthermore, the circuit board 16 also has a temperature detection circuit mounted on it that detects temperature abnormalities of the battery cells 1.

[0060] (Side elastic body 80) Furthermore, the power supply unit may be provided with one or more side elastic bodies 80 between the side of the core block 100 and the inner surface of the outer casing 20. By interposing such side elastic bodies 80, it is possible to suppress the situation in which the core block 100 collides with the inner wall of the outer casing 20 and is damaged when an impact is applied to the power supply unit from the side.

[0061] As shown in Figure 4, the side elastic body 80 is a rod-shaped extension in the connecting direction Dc of the battery block 10. It is also preferable to provide multiple side elastic bodies 80. By arranging multiple side elastic bodies 80 between, for example, both sides of the core block 100 and the inner surface of the outer case 20, the core block 100 can be protected within the outer case 20 from impacts from either the left or right side. As such side elastic bodies 80, rubber materials with excellent elasticity can be used, such as fluororubber, isoprene rubber, styrene-butadiene rubber, butadiene rubber, chloroprone rubber, nitrile rubber, hydrogenated nitrile rubber, polyisobutylene rubber, ethylene propylene rubber, ethylene vinyl acetate copolymer rubber, chlorosulfonated polyethylene rubber, acrylic rubber, epichlorohydrin rubber, urethane rubber, silicone rubber, thermoplastic olefin rubber, ethylene propylene diene rubber, butyl rubber, polyether rubber, etc.

[0062] Furthermore, it is preferable that the side elastic body 80 forms a narrowed portion 82 along the connection direction Dc of the battery block 10. This configuration has the advantage of making it easier to press-fit the core block 100 into the outer case 20 by partially reducing the pressure at the narrowed portion 82.

[0063] (Manufacturing method for power supply devices) A method for manufacturing a power supply device having the above configuration will now be described. First, multiple battery blocks 10 are connected in one direction with multiple holder through holes 12 opened in each battery block 10 aligned. Then, a shaft portion 50 is inserted into each holder through hole 12, and the threads 51 formed at least at the tip of each shaft portion 50 are screwed into the first cover portion 30 placed on the end face of the core block 100 to fix it in place. In this state, the core block 100 is inserted from the first open end 21, which is one open end of the outer case 20, and the first open end 21 is closed with the first cover portion 30. Furthermore, the second open end 22, which is the other open end of the outer case 20, is closed with the second cover portion 40. In this way, the core block 100 can be fixed to the first cover portion 30 by the shaft portion 50 that passes through the core block 100, which is made up of multiple battery blocks 10 connected together, thus eliminating the need to fix each battery block 10 individually. Furthermore, this design offers the advantage of stably securing the core block 100 housed within the outer casing 20. As a result, even if the power supply is subjected to external forces such as drops or vibrations, the core block 100 remains stably fixed within the outer casing 20, providing protection against breakage or damage to internal components. [Industrial applicability]

[0064] The power supply device and its manufacturing method described herein are suitable for use as a power supply device attached to an electric vehicle to supply power to a drive motor, such as an electric assist bicycle, electric motorcycle, electric wheelchair, electric tricycle, electric cart, etc. [Explanation of symbols]

[0065] 1000,2000 power supplies 100, 100B core block 1 battery cell 10 Battery Blocks 11 Battery holder 11a, 11b Cell holder 12 holder through holes 13 Insertion tube 14 Lead Plate 15 Wiring board 16 Circuit boards 17 Connecting protrusion 18. PCB holder 20 outer cases 21 First open end 22 Second open end 23 First screw hole 24 Second screw hole 30,30B First lid part 31 First threaded section 32 First step wall 33 First insertion hole 34 Insert Nuts 40 Second lid part 41 Second threaded section 42 Second step wall 43 Second insertion hole 50 Shaft section 51,51B Screw Mountain 52 Screw heads 60 First Packing 61 First guard section 62 First fold 70 Second packing 71 Second guard section 72 Second pleat section 74 Protrusion 80 Side elastic body 82 Stenosis Dc connection direction

Claims

1. Each has multiple battery cells connected in series or parallel, and multiple battery blocks have multiple holder through-holes formed therein, With the plurality of battery blocks connected in the connecting direction in a position where the plurality of holder through holes are aligned, a plurality of shaft portions are inserted through each of the plurality of holder through holes, An outer case that houses the aforementioned plurality of battery blocks, having openings at both ends to form a first open end and a second open end, A first lid portion that closes the first open end of the outer case, A second lid portion that closes the second open end of the outer case, Equipped with, Each of the aforementioned multiple shaft portions has a screw thread formed at least at its tip. The aforementioned plurality of battery blocks are connected in the connection direction to form a core block. A power supply device in which the multiple shaft portions are inserted through the multiple holder through holes of the multiple battery blocks of the core block, and the first cover portion is fixed to the multiple shaft portions by the screw threads.

2. A power supply device according to claim 1, The first lid portion further comprises a plurality of insert nuts embedded in it, A power supply device in which the plurality of insert nuts are meshed with the threads of the plurality of shafts when the plurality of shafts are inserted through the plurality of holder through holes in the core block.

3. A power supply device according to claim 1, With the core block, on which the first lid portion is fixed by the plurality of shaft portions, inserted from the first open end of the outer case, the core block further comprises a plurality of first screw portions that fix the first lid portion to the first open end of the outer case, The power supply device is provided with a plurality of first screw holes at the edge of the first open end, into which the plurality of first screw portions are screwed.

4. A power supply device according to claim 3, The first packing is further interposed at the interface between the first lid and the outer case, The power supply device wherein the first packing is located on the inner surface side of the outer casing, as viewed from the first open end, beyond the plurality of first screw holes.

5. A power supply device according to claim 4, A power supply device in which the plurality of first screw portions are located outward from the end face of the outer casing, compared to the plurality of shaft portions.

6. A power supply device according to claim 1, With the core block, to which the first lid portion is fixed by the plurality of shaft portions, inserted from the first open end of the outer case, the system further comprises a plurality of second screw portions that fix the second lid portion to the second open end of the outer case while pressing the core block, The power supply device is provided with a plurality of second screw holes at the edge of the second opening, into which the plurality of second screw portions are screwed.

7. A power supply device according to claim 6, The system further comprises a second packing interposed at the interface between the second lid and the outer case, The power supply device wherein the second packing is located on the inner surface side of the outer casing, as viewed from the second open end, beyond the plurality of second screw holes.

8. A power supply device according to claim 7, The power supply device wherein the second packing has a projection that protrudes toward the interface with the outer casing along the connecting direction.

9. A power supply device according to claim 7, A power supply device in which the plurality of second screw portions are located outward from the end face of the outer casing, compared to the plurality of shaft portions.

10. A power supply device according to any one of claims 1 to 9, A substrate holder is disposed on one end face of the core block, which connects the plurality of battery blocks, and on the end face facing the second lid; A circuit board held in the aforementioned substrate holder, Furthermore, The substrate holder has multiple holder insertion holes through which the multiple shaft portions are inserted, Each of the aforementioned multiple shaft portions has a screw head provided on the opposite side of the screw threads, The plurality of shaft portions are inserted through the plurality of holder insertion holes of the substrate holder, A power supply device in which the screw head is installed and fixed to the substrate holder.

11. A power supply device according to any one of claims 1 to 9, A power supply device further comprising one or more lateral elastic bodies extending in the connecting direction, disposed between any side surface of the core block and the inner surface of the outer casing.

12. A power supply device according to claim 11, The power supply device has a side elastic body having a narrowed portion in which the width is locally reduced along the connecting direction.

13. The process involves preparing multiple battery blocks, each consisting of multiple battery cells connected in series or parallel, The process involves connecting the multiple battery blocks in the connecting direction in an orientation where the multiple holder through-holes opened in each of the aforementioned battery blocks are aligned, forming a core block; inserting multiple shaft portions into the holder through-holes; and screwing the threads formed at least at the tip of each shaft portion into a first lid portion positioned on the end face of the core block to secure it. The process of preparing an outer case having openings at both ends to form a first open end and a second open end, The process of inserting the core block from one of the first open ends of the outer casing, The process of closing the second open end of the outer case with the second lid, A method for manufacturing a power supply device, including the method described above.

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