Power supply device, vehicle equipped with same, and power storage device

Abstract

This power supply device (100) comprises: a battery laminate (10) in which a plurality of square battery cells (1) are laminated; a plan view rectangular end plate (20) having a pressing surface which covers an end surface of the battery laminate (10); and a fastening member (15) which fastens the battery laminate (10). The end plate (20) forms, on the pressing surface, flat pressing regions (25) respectively formed on the end edge sides in the up-down direction, and a bead region (26) which is formed on the middle side in the up-down direction and curves to a shape projecting to the back surface side of the pressing surface. The foregoing allows the pressing regions (25) for pressing the battery laminate (10) to remain on the end plate (20), while making it possible to improve strength by changing the shape forming the bead region (26) in the middle. Thus, a high-strength end plate (20) can be provided inexpensively.

Description

[Technical field]

[0001] The present disclosure relates to a power supply device, a vehicle including the same, and a power storage device. [Background technology]

[0002] 2. Description of the Related Art Power supply devices such as battery modules and battery packs each having a plurality of battery cells are used as power sources for vehicles such as hybrid cars and electric cars, and as power sources for factory and home power storage systems.

[0003] Such a power supply device has a plurality of stacked chargeable and dischargeable battery cells. For example, as shown in the schematic cross-sectional view of Fig. 12, a power supply device 900 has end plates 903 disposed on both end faces of a battery stack 910 in which rectangular exterior can battery cells 901 are stacked, and the end plates 903 are fastened together by bind bars 904. Furthermore, the rectangular battery cells 901 have positive and negative electrode terminals 902 provided at a distance on their top faces. The electrode terminals 902 of adjacent battery cells 901 are connected by a bus bar 940.

[0004] In such a structure in which the end plates press and fasten the battery stack, the end plates need to have sufficient strength. Generally, increasing the strength of the end plates increases costs. For example, end plates that use two metal sheets to ensure strength are expensive. Furthermore, when mechanical clinching is used to fasten the end plates and bind bars (see Patent Document 1), the equipment size for mechanical clinching is large, and it becomes necessary to avoid interference during processing on the power supply device side, resulting in a problem of the size of the power supply device increasing. [Prior art documents] [Patent documents]

[0005] [Patent Document 1] JP 2013-69657 A Summary of the Invention [Problem to be solved by the invention]

[0006] An object of one embodiment of the present invention is to provide a power supply device that achieves reduced costs while maintaining the strength of an end plate, and a vehicle and a power storage device that are provided with the power supply device. [Means for solving the problem]

[0007] A power supply device according to one aspect of the present invention comprises a battery stack comprising a plurality of stacked rectangular battery cells, an end plate which is rectangular in plan view and has a pressing surface which covers an end face of the battery stack, and a fastening member which fastens the battery stack, the end plate defining flat pressing areas formed on each of the upper and lower edge sides of the pressing surface, and a bead area formed on the middle side in the vertical direction and bent into a shape which protrudes towards the rear side of the pressing surface. Effect of the Invention

[0008] In one aspect of the power supply device of the present invention, the strength can be improved by changing the shape of the end plate to form a bead area in the middle while still leaving a pressing area in the end plate to press against the battery stack, thereby making it possible to provide high-strength end plates at low cost. [Brief description of the drawings]

[0009] [Figure 1] 1 is a perspective view showing a power supply device according to a first embodiment of the present invention. [Diagram 2] FIG. 2 is an exploded perspective view of the power supply device shown in FIG. [Diagram 3] 2 is an enlarged perspective view of an end plate portion of the power supply device of FIG. 1. [Figure 4] 2 is a vertical cross-sectional view of an end plate portion of the power supply device of FIG. 1. [Diagram 5] FIG. 5A is a schematic vertical cross-sectional view of an end plate in which the bead region is formed in a curved shape, and FIG. 5B is a schematic cross-sectional view of an end plate in which the bead region is formed in a U-shape. [Figure 6]6A is a schematic vertical cross-sectional view taken along line VIA-VIA in FIG. 3, and FIG. 6B is a schematic vertical cross-sectional view taken along line VIB-VIB in FIG. [Figure 7] FIG. 11 is a vertical cross-sectional view of an end plate portion of a power supply device according to a second embodiment. [Figure 8] FIG. 11 is a vertical cross-sectional view of an end plate portion of a power supply device according to a third embodiment. [Figure 9] 1 is a block diagram showing an example of a power supply device mounted on a hybrid vehicle that runs on an engine and a motor. [Figure 10] FIG. 1 is a block diagram showing an example in which a power supply device is mounted on an electric vehicle that runs only on a motor. [Figure 11] FIG. 11 is a block diagram showing an example of application to a power supply device for power storage. [Figure 12] FIG. 13 is an exploded perspective view showing a conventional power supply device. [Figure 13] FIG. 11 is an exploded perspective view of an end plate portion of a power supply device according to a fourth embodiment. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0010] The embodiment of the present invention may be specified by the following configurations.

[0011] In addition to the above configuration, a power supply device according to an embodiment of the present invention has a side wall formed on each side of the pressing surface of the end plate, and the side walls have fixing regions for fixing the fastening member at positions corresponding to the pressing regions on the vertical edge sides, and the fixing regions are connected to the protruding shape of the bead region at the vertical center portion. With the above configuration, while the fixing regions for connecting the end plate to the fastening member are secured on both side surfaces of the end plate, the center portion is continuous with the protruding shape of the bead region to ensure strength.

[0012] In a power supply device according to another embodiment of the present invention, in addition to any of the above configurations, the end plate has a curved protruding shape of the bead region. This configuration makes it possible to avoid stress concentration compared to a configuration in which the bead region is bent in a U-shape, and to disperse stress and improve the strength of the end plate.

[0013] In addition to any of the above configurations, a power supply device according to another embodiment of the present invention has a side wall of the end plate that is curved continuously with the bead region at a central portion. With the above configuration, a region for connecting the end plate to a fastening member is provided on the side wall of the end plate, while the central portion is continuous with the protruding portion of the bead region to ensure strength.

[0014] Furthermore, in addition to any of the above configurations, in a power supply device according to another embodiment of the present invention, the end plates have a protruding shape of the bead region that protrudes steeply in the center of the left and right sides in a vertical cross-sectional view and gradually slopes toward both sides. With the above configuration, the center portion is brought closer to a protruding strip to improve strength, while the side walls of the end plates at the ends secure the fixing portion with the fastening member.

[0015] Furthermore, in addition to any of the above configurations, the power supply device according to another embodiment of the present invention has an end plate formed by pressing a single metal plate, which makes it possible to reduce the cost and weight of the end plate.

[0016] Furthermore, in addition to any of the above configurations, a power supply device according to another embodiment of the present invention is configured such that, in a cross-sectional view, the sum of the heights of the pressing regions formed at the top and bottom of the end plate is equal to the height of the bead region formed in the middle. With the above configuration, it is possible to achieve a good balance between the pressing force and rigidity of the end plate.

[0017] Furthermore, in a power supply device according to another embodiment of the present invention, in addition to any of the above configurations, the end plates are fixed to the fastening members by welding or crimping. With the above configuration, it is possible to increase the strength of the end plates while ensuring the fixed portions with the fastening members.

[0018] Furthermore, an electric vehicle according to another embodiment of the present invention includes any of the power supply devices described above, a motor for driving supplied with power from the power supply device, a vehicle body mounting the power supply device and the motor, and wheels driven by the motor to drive the vehicle body.

[0019] Furthermore, an energy storage device according to another embodiment of the present invention comprises any of the power supply devices described above and a power supply controller that controls charging and discharging to the power supply device, and the power supply controller enables charging of the battery cells using external power and controls charging of the battery cells.

[0020] Hereinafter, an embodiment of the present invention will be described based on the drawings. However, the embodiment shown below is an example for embodying the technical idea of ​​the present invention, and the present invention is not limited to the following. In addition, this specification never specifies the members shown in the claims to the members of the embodiment. In particular, the dimensions, materials, shapes, and relative arrangements of the components described in the embodiment are not intended to limit the scope of the present invention to those, and are merely explanatory examples, unless otherwise specified. Note that the size and positional relationship of the components shown in each drawing may be exaggerated to clarify the explanation. Furthermore, in the following explanation, the same name and symbol indicate the same or similar components, and detailed explanations will be omitted as appropriate. Furthermore, each element constituting the present invention may be configured as a form in which multiple elements are composed of the same member, and one member serves multiple elements, or conversely, the function of one member can be shared and realized by multiple members. In addition, the contents described in some examples and embodiments may be applicable to other examples, embodiments, etc.

[0021] The power supply device according to the embodiment is used for various purposes, such as a power supply mounted on an electric vehicle such as a hybrid car or an electric car to supply power to a driving motor, a power supply for storing power generated by natural energy such as solar power generation or wind power generation, or a power supply for storing late-night power, and is particularly used as a power supply suitable for large power and large current applications. In the following example, an embodiment applied to a power supply device for driving an electric vehicle will be described. [Embodiment 1]

[0022] A power supply device 100 according to a first embodiment of the present invention is shown in Figs. 1 and 2. In these figures, Fig. 1 is a perspective view of the power supply device 100 according to the first embodiment, and Fig. 2 is an exploded perspective view of the power supply device 100 shown in Fig. 1. The power supply device 100 shown in these figures comprises a battery stack 10 in which multiple battery cells 1 are stacked with insulating spacers 16 between them, a pair of end plates 20 covering both side faces of the battery stack 10, multiple fastening members 15 that fasten the end plates 20 together, and a bus bar 40 provided on the upper surface of the battery stack 10. The fastening members 15 are formed in a plate shape that extends in the stacking direction of the multiple battery cells 1. The fastening members 15 are arranged on opposite side faces of the battery stack 10 and fasten the end plates 20 together. (Battery stack 10)

[0023] As shown in FIG. 2, the battery stack 10 includes a plurality of battery cells 1 each having positive and negative electrode terminals 2, and bus bars 40 that are connected to the electrode terminals 2 of the battery cells 1 and connect the battery cells 1 in parallel and in series. The battery cells 1 are connected in parallel and in series via the bus bars 40. The battery cells 1 are rechargeable secondary batteries. In the power supply device 100, the battery cells 1 are connected in parallel to form parallel battery groups, and the parallel battery groups are connected in series to connect many battery cells 1 in parallel and in series. The power supply device 100 shown in FIG. 2 stacks the battery cells 1 to form the battery stack 10. A pair of end plates 20 are arranged on both end faces of the battery stack 10. The ends of fastening members 15 are fixed to the end plates 20 to fix the stacked battery cells 1 in a pressed state. (Battery cell 1)

[0024] As shown in FIG. 2, the battery cells 1 are rectangular batteries that are wider than their thickness, in other words thinner than their width, and are stacked in the thickness direction to form a battery stack 10. The battery cells 1 can be, for example, lithium-ion secondary batteries. The battery cells can also be any rechargeable secondary batteries, such as nickel-metal hydride batteries and nickel-cadmium batteries. The battery cells 1 house positive and negative electrode plates together with an electrolyte in an outer can 1a with a sealed structure. The outer can 1a is formed by pressing a metal plate such as aluminum or an aluminum alloy into a rectangular shape, and the opening is airtightly sealed with a sealing plate 1b. The sealing plate 1b is made of the same aluminum or aluminum alloy as the rectangular outer can 1a, and has positive and negative electrode terminals 2 fixed to both ends. Furthermore, the sealing plate 1b is provided with a gas exhaust valve 1c, which is a safety valve that opens in response to pressure changes inside the battery cells 1, between the positive and negative electrode terminals 2.

[0025] A plurality of battery cells 1 are stacked such that the thickness direction of each battery cell 1 is the stacking direction to form a battery stack 10. In this case, by stacking a larger number of battery cells than usual, it is possible to increase the output of the battery stack 10. In such a case, the battery stack 10 becomes elongated in the stacking direction. The battery cells 1 are arranged with their terminal surfaces 1X, on which the positive and negative electrode terminals 2 are provided, on the same plane, and the plurality of battery cells 1 are stacked to form the battery stack 10. The upper surface of the battery stack 10 is the surface on which the gas release valves 1c of the plurality of battery cells 1 are provided. (electrode terminal 2)

[0026] 2 etc., the battery cell 1 has a terminal surface 1X formed by a sealing plate 1b, which is the top surface, and positive and negative electrode terminals 2 are fixed to both ends of this terminal surface 1X. The electrode terminals 2 have cylindrical protrusions. However, the protrusions do not necessarily have to be cylindrical, and can also be polygonal or elliptical.

[0027] The positions of the positive and negative electrode terminals 2 fixed to the sealing plate 1b of the battery cell 1 are such that the positive and negative electrodes are symmetrical. As a result, as shown in Fig. 2, the battery cells 1 are stacked with the left and right sides reversed, and adjacent positive and negative electrode terminals 2 that are close to each other are connected by a bus bar 40, so that adjacent battery cells 1 can be connected in series. Note that the present invention does not specify the number of battery cells that make up the battery stack and their connection state. The number of battery cells that make up the battery stack and their connection state can be changed in various ways, including other embodiments that will be described later.

[0028] Multiple battery cells 1 are stacked so that the thickness direction of each battery cell 1 is the stacking direction to form a battery stack 10. In the battery stack 10, multiple battery cells 1 are stacked so that the terminal surfaces 1X on which the positive and negative electrode terminals 2 are provided, or the sealing plates 1b in Fig. 2, are on the same plane. In the battery stack 10, adjacent electrode terminals 2 are joined by metal bus bars 40 to connect the battery cells 1 in series. (Busbar 40)

[0029] Both ends of the bus bar 40 are connected to the positive and negative electrode terminals 2 to connect the battery cells 1 in series or in parallel. The power supply device 100 can increase the output voltage by connecting the battery cells 1 in series, and can increase the output voltage and output current by connecting the battery cells 1 in series and in parallel. (Insulating spacer 16)

[0030] In the battery stack 10, insulating spacers 16 are interposed between adjacent stacked battery cells 1. The insulating spacers 16 are made of an insulating material such as resin in the form of a thin plate or sheet. The insulating spacers 16 are plate-shaped and have a size approximately equal to the opposing surfaces of the battery cells 1. The insulating spacers 16 are stacked between adjacent battery cells 1 to insulate the adjacent battery cells 1 from each other. Note that the spacers placed between adjacent battery cells may be spacers that are shaped to form a flow path for cooling gas between the battery cells and the spacer. The surfaces of the battery cells may also be covered with an insulating material. For example, the surface of the exterior can, excluding the electrode terminals of the battery cells, may be covered with a shrink film such as PET resin.

[0031] Furthermore, the power supply device 100 shown in Fig. 2 has end plates 20 disposed on both end faces of the battery stack 10. Note that end plate 20 and battery stack 10 may be insulated by interposing end spacers 17 between them. The end spacers 17 can also be made into thin plate or sheet shapes from an insulating material such as resin.

[0032] In the power supply device 100 of embodiment 1, a battery stack 10 is formed in which a number of battery cells 1 are stacked on top of each other, and the electrode terminals 2 of adjacent battery cells 1 are connected to each other by bus bars 40, thereby connecting the battery cells 1 in parallel and in series.

[0033] 2, the end plates 20 are arranged on both ends of the battery stack 10 and are fastened via a pair of left and right fastening members 15 arranged along both side surfaces of the battery stack 10. The end plates 20 are located on the outsides of the end spacers 17, at both ends of the battery stack 10 in the stacking direction of the battery cells 1, and sandwich the battery stack 10 from both ends. (Fastening member 15)

[0034] Both ends of the fastening members 15 are fixed to end plates 20 arranged on both end faces of the battery stack 10. The end plates 20 are fixed using a plurality of fastening members 15, thereby fastening the battery stack 10 in the stacking direction. As shown in FIG. 2 etc., each fastening member 15 is made of metal and has a predetermined width and thickness that fits along the side of the battery stack 10, and is arranged facing both side faces of the battery stack 10. These fastening members 15 can be made of a metal plate such as iron, preferably a steel plate. The fastening members 15 made of metal plate are bent by press forming or the like to be formed into a predetermined shape.

[0035] The fastening member 15 has a plate-shaped main fastening surface 15a bent at the top and bottom into a U-shape to form bent pieces 15d. The top and bottom bent pieces 15d cover the top and bottom corners of the left and right sides of the battery stack 10.

[0036] A power supply device 100 in which many battery cells 1 are stacked is configured to restrain the multiple battery cells 1 by connecting end plates 20 arranged on both ends of a battery stack 10 made up of the multiple battery cells 1 with fastening members 15. By restraining the multiple battery cells 1 via the highly rigid end plates 20 and fastening members 15, it is possible to suppress the expansion, deformation, relative movement, and malfunction due to vibration of the battery cells 1 that accompanies charging / discharging and deterioration. (Insulation sheet 30)

[0037] An insulating sheet 30 is interposed between the fastening members 15 and the battery stack 10. The insulating sheet 30 is made of an insulating material, such as resin, and provides insulation between the metal fastening members 15 and the battery cells 1. The insulating sheet 30 shown in FIG. 2 and other figures is made of a flat plate 31 that covers the side surfaces of the battery stack 10, and folded covering portions 32 provided above and below the flat plate 31. The folded covering portions 32 are folded in a U-shape from the flat plate 31 so as to cover the folded pieces 15d of the fastening members 15, and then folded back again. In this way, the folded pieces 15d are covered from the top surface to the side surfaces and bottom surface with the insulating folded covering portions, thereby preventing unintended electrical connection between the battery cells 1 and the fastening members 15.

[0038] Additionally, the bent pieces 15d press against the top and bottom surfaces of the battery cells 1 of the battery stack 10 via the folded covering portions 32. As a result, each battery cell 1 is pressed from above and below by the bent pieces 15d to hold it in the height direction, and even if vibrations, shocks, etc. are applied to the battery stack 10, each battery cell 1 can be kept from shifting position in the vertical direction.

[0039] Note that if the battery stack or the surface of the battery stack is insulated, for example if the battery cells are housed in an insulating case or covered with a resin heat-shrinkable film, or if the surfaces of the fastening members are coated with an insulating paint or coating, or if the fastening members are made of an insulating material, then the insulating sheet may be unnecessary. Also, for the insulating sheet 30, if there is no need to consider insulation from the folded pieces 15d of the fastening members 15 on the underside of the battery stack 10, the folded covering portion 32 may be formed only on the upper end side. For example, this would be the case if the battery cells are covered with a heat-shrinkable film. (End plate 20)

[0040] The details of the end plate 20 will be described with reference to Figs. 3 and 4. In these figures, Fig. 3 shows an enlarged perspective view of the end plate 20 of the power supply device 100 of Fig. 1, and Fig. 4 shows a vertical cross-sectional view of the end plate 20 of the power supply device 100 of Fig. 1. The end plate 20 shown in these figures has a rectangular outer shape in a plan view, and is formed into a frame-like shape 21 with a protruding periphery. The rectangular area surrounded by the frame-like shape 21 is used as a pressing surface that covers the end face of the battery stack 10. By forming the frame-like shape 21 around the pressing surface in this manner, the strength of the pressing surface can be increased. The upper surface side of the frame-like shape 21 may be formed with screw holes or notches for connecting to other parts as necessary. Furthermore, the end plate 20 has pressing areas 25 formed on the upper and lower edge sides of the pressing surface, and a bead area 26 is formed between the pressing areas 25. (Pressure area 25)

[0041] The upper and lower pressing regions 25 each have a flat surface and press against the battery stack 10. Preferably, the upper and lower pressing regions 25 have approximately the same width. Also, it is preferable that the pressing regions 25, including the bead region 26, are formed line-symmetrically in the horizontal direction. (Bead area 26)

[0042] On the other hand, the bead region 26 is formed in the vertical middle of the pressing surface and is bent into a shape that protrudes toward the back side of the pressing surface. With this configuration, while leaving the pressing region 25 that presses the battery stack 10 in the end plate 20, the strength can be improved by changing the shape to form the bead region 26 in the middle, so that a high-strength end plate 20 can be provided at low cost.

[0043] When the end plate 20 is formed from sheet metal, the end plate 20 having the bead region 26 has a shape that has a space on the battery cell 1 side. For this reason, it is preferable to place an end surface spacer 17D between the battery cell 1 and the end plate 20D, as in the power supply device 400 according to embodiment 4 shown in Fig. 13. Specifically, as shown in Fig. 13, the end surface spacer 17D has a protrusion 17d that protrudes toward the recess of the end plate 20D (the back surface of the bead region 26D), allowing force to be transferred between the battery cell 1 and the end plate 20D over the entire surface. (Side wall 22)

[0044] On the other hand, the end plate 20 has a frame 21 formed around the periphery of the pressing surface. In this frame 21, both sides of the side surface of the pressing surface are formed as side walls 22. The side walls 22 have fixing regions 23 for fixing to the fastening member 15 at positions corresponding to the pressing regions 25 on the upper and lower edge sides. The fixing regions 23 are formed in the same plane on the top and bottom. The fixing regions 23 are also flat. The end plate 20 is fixed to the fastening member 15 by the fixing regions 23. Welding or caulking are preferable for fixing the end plate 20 and the fastening member 15. For example, spot welding, clinching, etc. can be used. Also, screwing using bolts or the like may be used.

[0045] Furthermore, the side wall 22 is connected to the protruding shape of the bead region 26 between these fixing regions 23, i.e., at the center in the vertical direction. In other words, the fixing region 23 for connecting with the fastening member 15 is not provided in the middle of the height direction of the side wall 22. In this way, the bead region 26 is penetrated so as to horizontally cross the pressing surface as shown in Fig. 3 etc., thereby maintaining the protruding shape of the bead region 26 and exerting the reinforcing structure of the end plate 20. On the other hand, the fixing regions 23 for fixing with the fastening member 15 are provided above and below the side wall 22, and a fixing structure for fixing the end plate 20 to the fastening member 15 is also established.

[0046] The protruding shape of the bead region 26 is preferably curved as shown in the schematic cross-sectional view of Fig. 5A. This makes it possible to avoid stress concentration compared to the end plate 20X having the bead region 26X bent in a U-shape as shown in Fig. 5B, and to disperse stress and improve the strength of the end plate 20.

[0047] In addition, it is preferable that the side wall 22 of the end plate 20 is formed so as to be continuously curved and connected to the bead region 26 at the center in the vertical direction. This ensures that the side wall 22 of the end plate 20 has an area for connecting the end plate 20 to the fastening member 15, while the center portion is continuous with the protruding portion of the bead region 26 to ensure strength.

[0048] Furthermore, it is preferable that the protruding shape of the bead region 26 is formed so that, in a vertical cross-sectional view, the central portion on the left and right sides protrudes relatively steeply as shown in Fig. 6A, but gradually slopes toward both sides as shown in Fig. 6B. In this way, the protruding shape is made tighter in the middle of the pressing surface in the left and right direction, where the strength is relatively weak, to increase the strength, while the end portion of the pressing surface can be deformed to secure the fixing region 23 for fixing the fastening member 15 to the side wall 22 of the end plate 20.

[0049] In addition, while the end plate 20 has the pressing area 25 and the bead area 26 continuously formed on the pressing surface, it is preferable that the boundary with the side wall 22 is slightly inclined in the protruding direction of the side wall 22, i.e., in the direction toward the back side of the pressing surface, as shown in Fig. 3. By processing in this manner, it is possible to alleviate stress concentration at the boundary between the pressing surface and the side wall 22, and also reduce the risk of damage to the boundary between the pressing surface and the side wall 22.

[0050] Such an end plate 20 can be formed by bending a single metal plate by press working. This makes it possible to maintain the necessary strength while using only one metal plate, rather than using two metal plates as in the conventional end plate, and also to reduce costs and weight. The end plate 20 is preferably formed by processing a metal plate such as SUS or high tensile steel plate.

[0051] Furthermore, when fixing the end plate 20 of this configuration to the fastening member 15, there is no need to increase the size of the power supply unit as in the past in order to avoid interference between the power supply unit and equipment for fastening processing such as mechanical clinching.

[0052] Furthermore, it is preferable to design the end plate 20 so that, in a cross-sectional view, the sum of the heights of the pressing regions 25 formed at the top and bottom is approximately equal to the height of the bead region 26 formed in the middle. For example, in Fig. 4, which is a vertical cross-sectional view of the end plate 20 at the middle in the width direction, if the height of the upper pressing region 25 is b1, the height of the bead region 26 is a, and the height of the lower pressing region 25 is b2, it is preferable that a = b1 + b2. Designing in this way makes it possible to achieve a good balance between the pressing force and rigidity of the end plate 20. [Embodiment 2]

[0053] In the above embodiment 1, an example in which one bead region 26 is provided in the center of the end plate 20 in the vertical direction is shown, but the present invention is not limited to the number of bead regions being one, and multiple bead regions may be provided. As an example, the power supply device 200 according to embodiment 2 shown in the schematic cross-sectional view of FIG. 7 shows a configuration in which two bead regions 26B are provided in the end plate 20B. By providing multiple bead regions 26B in this way, the strength of the end plate 20B can be further increased. In addition, the pressing regions 25B are also distributed and arranged in three, so that the end face of the battery stack 10 can be pressed more uniformly. Furthermore, in the side wall 22 of the end plate 20B, the fixing region 23B can be provided not only at the upper and lower edges but also in the middle, so that the reliability of the fixing between the end plate 20B and the fastening member 15 can be improved. In the power supply device 200 according to embodiment 2, the same members as those in embodiment 1 described above are given the same reference numerals and detailed description is omitted as appropriate. [Embodiment 3]

[0054] In the above example, the end plate is bent to provide a bead region, and the pressing surface is pressed against the battery stack to fasten the end plate. However, the present invention is not limited to an example in which the bead region of the end plate is hollow, but may be solid. Such an example is shown in the schematic cross-sectional view of FIG. 8 as a power supply device 300 according to embodiment 3. Note that in the power supply device 300 according to embodiment 3, the same members as those in embodiment 1 described above are given the same reference numerals, and detailed description thereof will be omitted as appropriate.

[0055] The end plate 20C shown in FIG. 8 has a solid pressing surface, not a hollow. For example, the bead area 26 of the end plate 20C is filled with an insulating material 28 such as resin or rubber. The insulating material 28 may be configured to cover not only the bead area 26C but also the pressing area 25C. This allows the pressing surface that presses the battery stack 10 to be made of a uniform material, so that the end face of the battery stack 10 is pressed evenly and heat can be dissipated evenly. Furthermore, by filling the insulating material 28, the air layer is eliminated, improving the heat dissipation performance of the end face of the battery stack 10 compared to the configuration of FIG. 4 and the like in which an air layer is partially formed. Furthermore, the thermal coupling state with the end face of the battery stack 10 can be made uniform, resulting in uniform heat dissipation performance.

[0056] In this manner, it is possible to reduce the cost and weight of the end plate. The power supply device 100 can be used as a power source for a vehicle that supplies power to a motor that drives the electric vehicle. The power supply device 100 can be used as a power source for such vehicles, including hybrid cars and plug-in hybrid cars that run on both an engine and a motor, and electric cars that run only on a motor. The power supply device 100 is used as a power source for such vehicles. In addition, an example will be described in which a large capacity, high output power supply device is constructed by connecting a large number of the above-mentioned power supply devices 100 in series or parallel to obtain power to drive an electric vehicle, and further adding a necessary control circuit. (Power supply unit for hybrid vehicles)

[0057] FIG. 9 shows an example of a power supply device 100 mounted on a hybrid vehicle that runs on both an engine and a motor. The vehicle HV mounted with the power supply device 100 shown in this figure includes a vehicle body 91, an engine 96 and a motor 93 for running the vehicle body 91, wheels 97 driven by the engine 96 and the motor 93 for running, a power supply device 100 that supplies power to the motor 93, and a generator 94 that charges the battery of the power supply device 100. The power supply device 100 is connected to the motor 93 and the generator 94 via a DC / AC inverter 95. The vehicle HV runs on both the motor 93 and the engine 96 while charging and discharging the battery of the power supply device 100. The motor 93 is driven in an area where the engine efficiency is poor, such as during acceleration or low-speed running, to run the vehicle. The motor 93 is driven by power supplied from the power supply device 100. The generator 94 is driven by the engine 96 or by regenerative braking when braking the vehicle, and charges the battery of the power supply device 100. As shown in Fig. 9, the vehicle HV may be provided with a charging plug 98 for charging the power supply device 100. The power supply device 100 can be charged by connecting this charging plug 98 to an external power source. (Power supply unit for electric vehicles)

[0058] FIG. 10 shows an example in which the power supply device 100 is mounted on an electric vehicle that runs only by a motor. The vehicle EV equipped with the power supply device 100 shown in this figure includes a vehicle body 91, a motor 93 for driving the vehicle body 91, wheels 97 driven by the motor 93, the power supply device 100 that supplies power to the motor 93, and a generator 94 that charges the battery of the power supply device 100. The power supply device 100 is connected to the motor 93 and the generator 94 via a DC / AC inverter 95. The motor 93 is driven by power supplied from the power supply device 100. The generator 94 is driven by energy generated when the vehicle EV is regeneratively braked, and charges the battery of the power supply device 100. The vehicle EV also includes a charging plug 98, which can be connected to an external power source to charge the power supply device 100. (Power supply device for power storage device)

[0059] Furthermore, the present invention does not limit the use of the power supply device to a power supply for a motor that runs a vehicle. The power supply device according to the embodiment can also be used as a power supply for a power storage device that charges a battery with power generated by solar power generation, wind power generation, or the like and stores the power. Fig. 11 shows a power storage device that charges a battery of a power supply device 100 with a solar cell 82 and stores the power.

[0060] The power storage device shown in FIG. 11 charges a battery of a power supply device 100 with power generated by a solar cell 82 arranged on the roof or rooftop of a building 81 such as a house or a factory. This power storage device charges the battery of the power supply device 100 with a charging circuit 83 using the solar cell 82 as a charging power source, and then supplies power to a load 86 via a DC / AC inverter 85. For this reason, this power storage device has a charging mode and a discharging mode. The power storage device shown in the figure connects the DC / AC inverter 85 and the charging circuit 83 to the power supply device 100 via a discharge switch 87 and a charge switch 84, respectively. The discharge switch 87 and the charge switch 84 are switched ON / OFF by a power storage device power supply controller 88. In the charge mode, the power supply controller 88 switches the charge switch 84 to ON and the discharge switch 87 to OFF to allow charging from the charging circuit 83 to the power supply device 100. Furthermore, when charging is completed and the battery is fully charged, or when a predetermined charged capacity or more has been reached, the power supply controller 88 switches the charging switch 84 OFF and the discharging switch 87 ON to switch to a discharging mode, permitting discharging from the power supply device 100 to the load 86. Furthermore, if necessary, the charging switch 84 can be turned ON and the discharging switch 87 can be turned ON to supply power to the load 86 and charge the power supply device 100 at the same time.

[0061] Furthermore, although not shown, the power supply device can also be used as a power source for a power storage device that uses late-night power at night to charge and store electricity in a battery. A power supply device that is charged with late-night power is charged with late-night power, which is surplus electricity from power plants, and outputs electricity during the day when the power load is high, making it possible to limit daytime peak power to a low level. Furthermore, the power supply device can also be used as a power source that charges with both the output of solar cells and late-night power. This power supply device effectively uses both the power generated by solar cells and the late-night power, and can efficiently store electricity while taking into account the weather and power consumption.

[0062] The above-described power storage system can be suitably used for applications such as a backup power supply device that can be mounted on a computer server rack, a backup power supply device for wireless base stations for mobile phones and the like, a power storage power source for home or factory use, a power source for street lights, a power storage device combined with a solar cell, and a backup power supply for traffic lights and road traffic indicators. [Industrial Applicability]

[0063] The power supply device and the vehicle and power storage device equipped therewith according to the present invention can be suitably used as a large current power supply used for the power supply of motors driving electric vehicles such as hybrid cars, fuel cell cars, electric cars, and electric motorcycles. Examples include power supply devices for plug-in hybrid electric cars, hybrid electric cars, electric cars, etc. that can switch between EV driving mode and HEV driving mode. They can also be suitably used for applications such as backup power supply devices that can be mounted on the racks of computer servers, backup power supply devices for wireless base stations for mobile phones, etc., power supplies for home and factory storage, power supplies for street lights, power storage devices combined with solar cells, and backup power supplies for traffic lights, etc. [Explanation of symbols]

[0064] 100, 200, 300, 400, 900…Power supply 1. Battery cell 1X…Terminal surface 1a…Outer can 1b...Sealing plate 1c…Gas exhaust valve 2...Electrode terminal 10...Battery stack 15... fastening member; 15a... fastening main surface; 15d... bent piece 15f…Bolt 16…Insulating spacer 17, 17D...End face spacer 17d…Convex part 20, 20B, 20C, 20D, 20X...End plates 21…Frame shape 22…Side wall 23, 23B…Fixed area 25, 25B, 25C...Pressure area 26, 26B, 26C, 26D, 26X...Bead area 28...Insulating material 30: Insulation sheet; 31: Flat plate; 32: Folded covering portion 40…Busbar 81…Building 82…Solar cell 83…Charging circuit 84…Charging switch 85…DC / AC inverter 86…Load 87…Discharge switch 88…Power supply controller 91…Vehicle body 93…Motor 94…Generator 95…DC / AC inverter 96…Engine 97...Wheel 98…Charging plug 901…Battery cell 902...Electrode terminal 903…End plate 904…Binding bar 910...Battery stack 940…Busbar HV, EV...Vehicles

Claims

1. a battery stack formed by stacking a plurality of rectangular battery cells; an end plate having a rectangular shape in a plan view and a pressing surface that covers an end face of the battery stack; a fastening member for fastening the battery stack; Equipped with The end plate has a pressing surface. A flat pressing area is formed on each of the upper and lower edge sides, a bead region formed at a middle portion in the up-down direction and bent in a shape protruding toward a back surface of the pressing surface; It is formed, a power supply device in which an end surface spacer having a protrusion that is inserted into the recess is disposed between the battery cell and a recess on the rear side of the portion of the end plate where the bead region is provided.

2. 2. The power supply device according to claim 1, The end plate forms a side wall on each side of the pressing surface, The side wall is The vertical edge side has a fixing area for fixing to the fastening member at a position corresponding to the pressing area, A power supply device connected to the protruding shape of the bead region at the vertical center portion.

3. 3. The power supply device according to claim 1, The end plate has a curved protruding shape in the bead region.

4. 4. The power supply device according to claim 3, A power supply device, wherein the side wall of the end plate is formed so as to be continuously curved and connected to the bead region at a central portion.

5. 5. The power supply device according to claim 4, The end plates have a protruding shape of the bead region that protrudes steeply at the left and right central portions and gradually slopes toward both sides when viewed in vertical cross section.

6. The power supply device according to any one of claims 1 to 5, The end plate of the power supply device is formed by bending a single metal plate by press working.

7. The power supply device according to any one of claims 1 to 6, A power supply device in which the sum of the heights of the pressing regions formed on the upper and lower ends of the end plate is equal to the height of the bead region formed in the middle when viewed in cross section.

8. A vehicle equipped with the power supply device according to any one of claims 1 to 7, A vehicle comprising the power supply device, a motor for driving supplied with power from the power supply device, a vehicle body mounting the power supply device and the motor, and wheels driven by the motor to drive the vehicle body.

9. A power storage device comprising the power supply device according to any one of claims 1 to 7, A power storage device comprising the power supply device and a power supply controller that controls charging and discharging to the power supply device, the power supply controller enabling charging of the battery cells using external power and controlling the charging of the battery cells.

10. a battery stack formed by stacking a plurality of rectangular battery cells; an end plate having a rectangular shape in a plan view and a pressing surface that covers an end face of the battery stack; a fastening member for fastening the battery stack; A method for assembling a power supply device comprising: The pressing surface, a bead region formed at a middle portion in the up-down direction and bent in a shape protruding toward a back surface of the pressing surface; a flat pressing region formed between each of the bead regions and the upper and lower edge sides; The end plate having the structure A side wall is formed on each side of the pressing surface, The side walls have fixing regions for fixing the fastening members at positions corresponding to the pressing regions on the vertical edge sides, preparing the end plate, the end plate being connected to the protruding shape of the bead region at a central portion in a vertical direction; a step of fixing the fastening member and the fixing region of the side wall of the end plate by mechanical clinching using the space of the pressing region formed above and below the bead region; A method for assembling a power supply device comprising:

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