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

Abstract

This power supply device (100) comprises: a battery stack (10) in which a plurality of battery cells (1) are stacked, the battery cells each having an electrode terminal (2) formed on the upper surface thereof; a pair of end plates (20) that respectively cover end surfaces of the battery stack (10) in the stacking direction; a fastening member (15) for fastening the pair of end plates (20) to each other; and an insulating member (30) interposed between a side surface of the battery stack (10) and the fastening member (15). The insulating member (30) has, on a surface facing the battery stack (10), a groove (33) extending in the stacking direction of the battery stack (10).

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] Power supply devices are used as power supply devices for driving electric vehicles, power supply devices for storing electricity, etc. Such power supply devices are configured such that a plurality of chargeable and dischargeable battery cells are stacked in multiple layers and these multiple battery cells are connected in series or parallel to extract electric power from a total output terminal.

[0003] Since power supplies are used in a variety of environments, water may get inside the power supply. Even if a highly sealed exterior case is used, condensation may occur inside the exterior case due to temperature differences. If water accumulates inside the power supply, there is a risk that a short circuit will occur between battery cells with a potential difference through the water.

[0004] In such power supply devices, it is necessary to prevent unintended conduction due to condensation, water seeping in from the outside, etc. In particular, in power supply devices that form a battery stack in which many battery cells are stacked, a structure that avoids liquid junctions is necessary to increase safety. [Prior art documents] [Patent documents]

[0005] [Patent Document 1] International Publication No. 2013 / 179796 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 in which unintended conduction is unlikely to occur even when condensation occurs, and a vehicle and a power storage device including the power supply device. [Means for solving the problem]

[0007] A power supply device according to one aspect of the present invention includes a battery stack formed by stacking a plurality of battery cells having electrode terminals formed on their upper surfaces, a pair of end plates covering each end face in the stacking direction of the battery stack, fastening members fastening the pair of end plates together, and an insulating member interposed between a side surface of the battery stack and the fastening members, wherein the insulating member has a groove extending in the stacking direction of the battery stack on a surface facing the battery stack. Effect of the Invention

[0008] According to a power supply device according to an aspect of the present invention, even if condensation occurs, the grooves provided in the insulating member can facilitate drainage. [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] 4 is an enlarged schematic cross-sectional view showing the interface between a battery stack and an insulating member of the power supply device according to the first embodiment. FIG. [Figure 4] 10 is an enlarged schematic cross-sectional view showing the interface between a battery stack and an insulating member of a power supply device according to Embodiment 2. FIG. [Diagram 5] FIG. 11 is an enlarged schematic cross-sectional perspective view showing grooves formed in an insulating member of a power supply device according to a third embodiment. [Figure 6] 10 is an enlarged schematic cross-sectional view showing the interface between a battery stack and an insulating member of a power supply device according to Embodiment 4. FIG. [Figure 7] 13 is an enlarged schematic cross-sectional view showing a groove formed in an insulating member of a power supply device according to Embodiment 5. FIG. [Figure 8] 13 is an enlarged schematic cross-sectional view showing a groove formed in an insulating member of a power supply device according to Embodiment 6. FIG. [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. 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, the power supply device according to one embodiment of the present invention has a groove with a width that allows condensation water to be sucked in by capillary action. With the above configuration, when condensation water occurs, the condensation water is guided into the groove by capillary action, facilitating the drainage of the condensation water.

[0012] In a power supply device according to another embodiment of the present invention, in addition to any one of the configurations described above, the groove has a width of 0.01 mm to 1.0 mm.

[0013] In addition to any one of the configurations described above, a power supply device according to another embodiment of the present invention is arranged such that the insulating member has a water-repellent coating on a part of or the entire surface thereof.

[0014] In a power supply device according to another embodiment of the present invention, in addition to any of the configurations described above, the groove forms a step toward an opening surface of the groove when viewed in a cross section perpendicular to the extension direction of the groove.

[0015] In addition to any one of the configurations described above, a power supply device according to another embodiment of the present invention is arranged such that at least one of both ends of the groove is shaped to widen toward the ejection direction.

[0016] In a power supply device according to another embodiment of the present invention, in addition to any of the above configurations, the insulating member includes a flat plate covering a side surface of the battery stack and a covering portion covering a bottom surface of the battery stack, the flat plate and the covering portion extending in the stacking direction of the battery stack, and the groove is provided on the surface of the covering portion facing the battery stack.

[0017] In a power supply device according to another embodiment of the present invention, in addition to any of the above configurations, the insulating member includes a flat plate covering a side surface of the battery stack and a covering portion covering a bottom surface of the battery stack, the flat plate and the covering portion extend in the stacking direction of the battery stack, and the groove is provided on the surface of the flat plate facing the battery stack.

[0018] In addition to any one of the configurations described above, a power supply device according to another embodiment of the present invention is configured such that the groove is formed in a linear shape that is inclined with respect to the extension direction of the flat plate.

[0019] A vehicle according to another embodiment of the present invention is a vehicle comprising any one of the power supply devices described above, the power supply device, a motor for driving that is 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.

[0020] An energy storage device according to another embodiment of the present invention includes any of the power supply devices described above, the power supply device, 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 the charging of the battery cells.

[0021] 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.

[0022] 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.

[0023] 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.

[0024] 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]

[0025] A power supply device 100 according to a first embodiment of the present invention is shown in Figures 1 and 2. In these figures, Figure 1 shows an exploded perspective view of the power supply device 100 according to the first embodiment, and Figure 2 shows an exploded perspective view of the power supply device 100 shown in Figure 1.

[0026] The power supply device 100 shown in these figures comprises a battery stack 10 made up of multiple stacked battery cells 1, a pair of end plates 20 covering both side ends of the battery stack 10, a number of fastening members 15 fastening the end plates 20 together, a cover assembly 40 provided on the top surface of the battery stack 10, and an insulating member 30.

[0027] The fastening members 15 are formed in a plate shape that extends along the stacking direction of the multiple battery cells 1. The fastening members 15 are disposed on opposing side surfaces of the battery stack 10 and fasten the end plates 20 together. (Battery stack 10)

[0028] 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 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 these bus bars. The battery cells 1 are secondary batteries that can be charged and discharged. 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)

[0029] 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.

[0030] 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)

[0031] 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.

[0032] 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 in a reversed state, and adjacent positive and negative electrode terminals 2 that are close to each other are connected by a bus bar, 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.

[0033] 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, that is, the sealing plate 1b in FIG. 2, are on the same plane.

[0034] The battery stack 10 may have an insulating spacer 16 between adjacent stacked battery cells 1. The insulating spacer 16 is made of an insulating material such as resin in the shape of a thin plate or sheet. The insulating spacer 16 is in the shape of a plate having a size almost equal to the size of the opposing surfaces of the battery cells 1. The insulating spacer 16 can be stacked between adjacent battery cells 1 to insulate the adjacent battery cells 1 from each other. Note that, as the spacer to be placed between adjacent battery cells, a spacer having a shape that forms a flow path for cooling gas between the battery cell and the spacer can also be used. The surface of the battery cell can also be covered with an insulating material. For example, the surface of the exterior can excluding the electrode terminal portion of the battery cell can be covered with a shrink film such as PET resin. In this case, the insulating spacer may be omitted. In addition, in a power supply device in which multiple battery cells are connected in parallel or in series, insulating spacers are interposed between the battery cells connected in series to insulate them from each other, while no voltage difference occurs between adjacent exterior cans between battery cells connected in parallel to each other, so the insulating spacer between these battery cells can also be omitted.

[0035] 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.

[0036] In the power supply device 100 according to the first embodiment, a battery stack 10 in which a plurality of battery cells 1 are stacked on top of one another is configured such that the electrode terminals 2 of adjacent battery cells 1 are connected by a bus bar to connect the plurality of battery cells 1 in parallel and in series. A bus bar holder may be disposed between the battery stack 10 and the bus bar. By using the bus bar holder, the plurality of bus bars can be disposed in fixed positions on the upper surface of the battery stack while insulating the plurality of bus bars from one another and insulating the terminal surfaces of the battery cells from the bus bar. A cover assembly 40, which will be described later, may be integrated with the bus bar holder.

[0037] Busbars are manufactured by cutting and processing metal sheets into a desired shape. The metal sheets that make up the busbars can be made of metals that have low electrical resistance and are lightweight, such as aluminum sheets or copper sheets, or alloys of these. However, other metals that have low electrical resistance and are lightweight, or alloys of these metals, can also be used for the metal sheets of the busbars. (End plate 20)

[0038] 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)

[0039] Both ends of the fastening member 15 are fixed to end plates 20 arranged on both end surfaces of the battery stack 10. As shown in Figure 2 etc., each fastening member 15 is made of metal with a prescribed width and prescribed thickness that fits along the side surface of the battery stack 10, and is arranged facing both side surfaces of the battery stack 10. This fastening member 15 can be made of a metal plate such as iron, preferably a steel plate. The fastening member 15 made of a metal plate is bent by press forming or the like to be formed into a prescribed shape.

[0040] The fastening member 15 is formed by bending the top and bottom of the plate-shaped fastening main surface 15a 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 side surfaces of the battery stack 10. The fastening member 15 is fixed to the outer circumferential surface of the end plate 20 by screwing bolts 15f into multiple fastening screw holes opened in the fastening main surface 15a. Note that the method of fixing the fastening main surface 15a to the end plate 20 is not necessarily limited to screwing using bolts, and pins, rivets, etc. may also be used.

[0041] 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. (Cover assembly 40)

[0042] The power supply device 100 has a cover assembly 40 provided on the top surface of the battery stack 10. The cover assembly 40 constitutes a gas exhaust path that exhausts high-temperature, high-pressure gas to the outside of the power supply device 100 when the gas is exhausted from any of the battery cells 1 that make up the battery stack 10. The cover assembly 40 may also be configured to function as a busbar holder that holds the busbars. (insulating member 30)

[0043] An insulating member 30 is interposed between the fastening members 15 and the battery stack 10. The insulating member 30 is bent so as to cover the side surfaces and part of the bottom surface of the battery stack 10. The insulating member 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 member 30 shown in FIG. 2 and other figures is made up of a flat plate 31 that covers the side surfaces of the battery stack 10, and covering portions 32 provided above and below the flat plate 31. The flat plate 31 is in the shape of a plate that extends in the stacking direction of the battery stack 10. The covering portion 32 is bent from the flat plate 31 to cover part of the bottom surface of the battery stack 10.

[0044] The insulating member 30 is configured to be interposed between the battery stack 10 and the fastening member 15, but is not necessarily in close contact with the battery stack 10 or the fastening member 15. If a dimensional tolerance is set in consideration of ease of assembly, a gap will be formed between the insulating member 30 and the battery stack 10. In this state, moisture contained in the air in the gap may condense due to a temperature difference. In particular, if condensation water occurs between the battery stack 10 and the fastening member 15, the condensation water will accumulate inside the power supply device if it cannot be drained outside the power supply device. The condensation water that accumulates in this area will flow through the small gap between the battery stack and the insulating member to the upper surface side, increasing the possibility of a so-called liquid junction occurring, which causes the electrode terminal provided on the upper surface of the battery cell to be conductive with other conductive members, etc. (Groove 33)

[0045] Therefore, in the power supply device 100 according to this embodiment, attention is not focused on preventing the generation of condensation water itself, but on a structure for efficiently draining the generated condensation water to the outside of the power supply device. In other words, if the generated condensation water can be drained faster than the speed at which the condensation water is generated, the risk of liquid junctions can be reduced. Here, an insulating member 30 interposed between the side surface of the battery stack 10 and the fastening member 15 is provided with a groove 33 for draining condensation water generated between the battery stack 10 and the fastening member 15 to the outside of the power supply device.

[0046] Generally, if the fastening member 15 and the insulating member 30 can be completely attached to each other, no gaps will be generated. However, since the fastening member 15 and the insulating member 30 are flat, it is difficult to completely attach them to each other due to dimensional tolerances and ease of assembly. In particular, if there is a small gap, there is a risk that the capillary phenomenon will cause the condensed water to reach the electrode terminal 2 on the upper surface. In the power supply device 100 according to this embodiment, the insulating member 30 is configured to form a groove 33 on a part of the surface that contacts the battery stack 10 to promote drainage of the condensed water. Since the power supply device 100 according to this embodiment has the groove 33 as a path for guiding the condensed water, it is possible to prevent the condensed water from reaching the electrode terminal 2 on the upper surface of the battery cell through an unintended path. In particular, the width of the groove 33 is preferably set to a width that causes the capillary phenomenon. A narrow groove 33 is also expected to have the effect of absorbing the condensed water by the capillary phenomenon. For example, the width of the groove is set to 0.01 mm to 1.0 mm. Groove 33 is provided so as to provide a path along which condensed water can flow without causing any problems, and is configured so that the guided condensed water is drained to the outside of the power supply device.

[0047] In the example shown in the schematic cross-sectional view of FIG. 3, a groove 33 is formed in the covering portion 32. The groove 33 is formed along the length direction of the covering portion 32. As described above, when the insulating member 30 includes the flat plate 31 and the covering portion 32, the insulating member 30 is bent so as to cover the side surface and part of the bottom surface of the battery stack 10, and condensed water is likely to accumulate in the covering portion 32. However, by providing the configuration shown in FIG. 3, the condensed water generated near the covering portion 32 is drained to the outside of the power supply device, and the condensed water is prevented from accumulating in the covering portion 32. This makes it possible to prevent the condensed water accumulated near the covering portion 32 from being sucked up by the gap between the side surface of the battery stack and the insulating member 30 and propagating to the upper surface side of the battery cell 1. As a result, it is possible to prevent the electrode terminal 2 provided on the upper surface of the battery cell 1 from forming a liquid junction with other conductive parts due to the condensed water. [Embodiment 2]

[0048] In addition, the present invention does not limit the uneven groove 35 to the configuration shown in Fig. 3. For example, in the power supply device 200 according to the second embodiment, as shown in the schematic cross-sectional view of Fig. 4, the groove is formed not in the flat plate 31B of the insulating member 30B but in the covering portion 32B, and the groove is formed in a stepped shape toward the opening surface. 36 By forming the unevenness in a stepped shape in this way, a space for storing condensed water can be secured at a position separated from the gap between the side surface of the battery stack and the insulating member 30, and the wicking up of condensed water by capillary action between the side surface of the battery stack and the insulating member 30 can be more effectively prevented. [Embodiment 3]

[0049] Furthermore, the unevenness is not limited to being formed horizontally, but may be inclined. For example, it may be formed in a line inclined with respect to the extension direction of the flat plate 31. This forms a downward gradient, and the condensed water can be guided in a direction defined by the downward gradient, and safely discharged from the power supply device. For example, in the power supply device 300 according to the third embodiment, as shown in the schematic cross-sectional perspective view of FIG. 5, the uneven groove 35C formed in the covering part 32C, not in the flat plate 31C of the insulating member 30C, is formed with a downward gradient to the right in the figure. This makes it possible to discharge the accumulated condensed water from the insulating member 30 along the downward gradient of the groove 35c, while preventing the condensed water from creeping up due to capillary action by the groove 35C. [Embodiment 4]

[0050] Furthermore, in the above example, the groove 33 is provided in the covering portion 32, but the present invention does not limit the location where the capillary action blocking structure is provided to the covering portion, and the capillary action blocking structure may be provided at any position on the path where condensed water may cause unintended conduction due to capillary action. For example, in the power supply device 400 according to the fourth embodiment, as shown in the schematic cross-sectional view of Figure 6, a groove 35D is provided as a capillary action blocking structure not in the covering portion 32D of the insulating member 30D but in a part of the flat plate 31D. This makes it possible to prevent condensed water from running up the side surface of the battery stack 10 along the flat plate 31D.

[0051] The grooves 35 are preferably provided on the lower side of the flat plate 31. This makes it possible to prevent the condensed water from creeping up below the flat plate 31 and to prevent the condensed water from diffusing, thereby further improving safety. [Embodiment 5]

[0052] As described above, an inclined surface can be formed on a capillary action blocking structure such as unevenness. Here, the inclined surface is not limited to a linear inclination in one direction, and multiple inclined surfaces may be provided. For example, in the power supply device 500 according to the fifth embodiment, an insulating member 30E shown in the schematic cross-sectional view of FIG. 7 has a groove 35E formed in a flat plate 31E, not in a covering portion 32E, and has a mountain-like downward inclined surface on the left and right. This allows condensation water to be discharged to the left and right of the insulating member 30E in the figure, shortening the path length for discharge and expecting smoother discharge. [Embodiment 6]

[0053] Furthermore, the groove is not limited to a configuration in which it extends with a constant width, and may have a partially wider portion. For example, in the example of a power supply device 700 according to the seventh embodiment shown in the schematic cross-sectional view of Fig. 8, the groove 35G is formed in the covering portion 32G of the insulating member 30G so as to widen toward the discharge direction. This makes it easier for condensed water to be discharged from the gap between the flat plate 31G of the insulating member 30G and the battery stack.

[0054] Furthermore, a water-repellent coating may be formed on a part or the entire surface of the insulating member 30. Generally, the effect of capillary action is considered to be large when the liquid wets the tube, that is, when the adhesive force is large, so that the capillary action can be suppressed by increasing the water repellency.

[0055] With this configuration, it is possible to speed up the drainage even when the drainage channel for draining condensation water is small, for example when the depth of the channel is low or the width is narrow. This also allows for efficient drainage, making it possible to miniaturize the power supply device. Furthermore, although condensation water cannot be drained unless it accumulates to a certain amount due to surface tension, it can remain inside the power supply device, but by using the capillary phenomenon in reverse, it is possible to promote drainage, and there is an advantage in that condensation water can be drained early even when there is only a small amount of water.

[0056] The power supply device 100 described above can be used as a power supply for a vehicle that supplies power to a motor that drives an electric vehicle. The power supply can be used for electric vehicles such as hybrid cars and plug-in hybrid cars that run on both sides of the battery, or electric cars that run only on a motor, and is used as a power source for these vehicles. Note that, in order to obtain power to drive an electric vehicle, a large capacity, high output power supply device will be described as an example in which a large number of the above-mentioned power supply devices 100 are connected in series or parallel, and further a necessary control circuit is added to construct the power supply device. (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, 500, 700…power supplies 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...End surface spacer 20…End plate 30, 30B, 30C, 30D, 30E, 30G...Insulating material 31, 31B, 31C, 31D, 31E, 31G...flat plate 32, 32B, 32C, 32D, 32E, 32G...Coated part 33…Groove 35, 35C, 35D, 35E, 35G...grooved 36…Step 40…Cover assembly 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 HV, EV...Vehicles

Claims

1. a battery stack formed by stacking a plurality of battery cells, each having an electrode terminal formed on its upper surface; a pair of end plates covering respective end faces of the battery stack in the stacking direction; a fastening member for fastening the pair of end plates together; an insulating member interposed between a side surface of the battery stack and the fastening member; A power supply device comprising: the insulating member has a groove on a surface facing the battery stack, the groove extending in the stacking direction of the battery stack, A power supply device, wherein the groove has a width that allows condensation water to be sucked in by capillary action.

2. 2. The power supply device according to claim 1, The power supply device, wherein the groove has a width of 0.01 mm to 1.0 mm.

3. 3. The power supply device according to claim 1, The insulating member has a water-repellent coating on a part or the entire surface of the insulating member.

4. 4. A power supply device according to claim 1, A power supply device in which the groove has a step formed toward an opening surface of the groove in a cross-sectional view perpendicular to an extension direction of the groove.

5. 4. A power supply device according to claim 1, The groove has at least one end that is flared toward the discharge direction.

6. 6. A power supply device according to claim 1, the insulating member includes a flat plate that covers a side surface of the battery stack and a covering portion that covers a bottom surface of the battery stack, the flat plate and the covering portion extending in a stacking direction of the battery stack, The groove is provided on a surface of the covering portion that faces the battery stack.

7. 6. A power supply device according to claim 1, the insulating member includes a flat plate that covers a side surface of the battery stack and a covering portion that covers a bottom surface of the battery stack, the flat plate and the covering portion extending in a stacking direction of the battery stack, The groove is provided on a surface of the flat plate facing the battery stack.

8. 8. The power supply device according to claim 6 or 7, The groove is formed in a linear shape inclined with respect to the extension direction of the flat plate.

9. A vehicle equipped with the power supply device according to any one of claims 1 to 8, 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.

10. A power storage device comprising the power supply device according to any one of claims 1 to 8, 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.

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