JP2020161338A - Power storage device - Google Patents

Abstract

To provide a power storage device which can be made compact.SOLUTION: A power storage device includes power storage modules 4A and 4B laminated in a lamination direction D1, a conductive plate 5 held by the power storage modules 4A and 4B and electrically connecting them, a monitoring board 51 provided adjacently to the power storage modules 4A and 4B in a direction D2, and monitoring the voltages of the power storage modules 4A and 4B, and a connection member 52 for voltage monitoring electrically connecting the conductive plate 5 and the monitoring board 51 and extending in the direction D2. The power storage modules 4A and 4B each include an electrode laminate containing multiple bipolar electrodes laminated in the lamination direction D1, and the connection member 52 includes an edge 55 for connection with the conductive plate 5, an edge 56 for connection with the monitoring board 51, and a coupling part 57 for coupling the edges 55 and 56.SELECTED DRAWING: Figure 4

Description

One aspect of the present invention relates to a power storage device.

As a conventional power storage device, a power storage device including a plurality of bipolar batteries (storage modules) laminated via a conductive layer is known (see Patent Document 1). Each power storage module includes a laminate formed by laminating a plurality of bipolar electrodes via a separator. On the side surface of the laminated body, a sealing body for sealing between the bipolar electrodes adjacent to each other in the stacking direction is provided, and the electrolytic solution is housed in the internal space formed between the bipolar electrodes.

JP-A-2007-122977

In the power storage device as described above, the state of each power storage module may be monitored by detecting the voltage of each power storage module. Generally, the monitoring board for monitoring the voltage is provided outside the power storage device, and a wire harness is used to transmit the voltage of each power storage module to the monitoring board. In this case, a connector may be required to connect the power storage module and the monitoring board with the wire harness. As a result, the power storage device including the monitoring board may become large.

One aspect of the present invention is to provide a power storage device that can be miniaturized.

The power storage device according to one aspect of the present invention is sandwiched between the first power storage module and the second power storage module stacked along the first direction, the first power storage module and the second power storage module, and the first power storage module. A conductive plate that electrically connects the second power storage module is provided adjacent to the first power storage module and the second power storage module in the second direction intersecting the first direction, and the voltage of the first power storage module It includes a monitoring board that monitors the voltage of the second power storage module, and a connecting member for voltage monitoring that electrically connects the conductive plate and the monitoring board and extends along the second direction. Each of the first power storage module and the second power storage module includes an electrode laminate including a plurality of bipolar electrodes laminated along the first direction. The connecting member includes a first end portion connected to the conductive plate, a second end portion connected to the monitoring board, and a connecting portion connecting the first end portion and the second end portion.

According to one aspect of the present invention, the power storage device can be miniaturized.

FIG. 1 is a schematic perspective view showing a power storage device according to an embodiment. FIG. 2 is a schematic cross-sectional view taken along line II-II of FIG. FIG. 3 is a schematic cross-sectional view showing the internal configuration of the power storage module shown in FIG. FIG. 4 is an enlarged view of a part of the cross section shown in FIG. FIG. 5 is a schematic perspective view showing the connecting member shown in FIG. FIG. 6 is an enlarged view of a part of the cross section along the VI-VI line of FIG. FIG. 7 is a diagram for explaining a method of connecting the connecting member and the temperature sensor unit. FIG. 8A is a diagram showing a modified example of the connecting member. FIG. 8B is a diagram for explaining a method of pulling out the connecting member shown in FIG. 8A from the conductive plate. FIG. 9 is a diagram showing a modified example of the connection mode between the conductive plate and the connecting member. FIG. 10A is a diagram showing another modification of the connecting member. FIG. 10B is a diagram showing still another modification of the connecting member. FIG. 11A is a diagram showing still another modification of the connecting member. FIG. 11B is a diagram showing still another modification of the connecting member. FIG. 12 is a diagram showing still another modification of the connecting member. FIG. 13A is a diagram showing still another modification of the connecting member. FIG. 13B is a diagram for explaining a method of fixing the connecting member shown in FIG. 13A to the monitoring board. FIG. 14A is a diagram showing a modified example of the temperature sensor unit. FIG. 14B is a diagram showing another modification of the temperature sensor unit. FIG. 15 is a diagram showing a modified example of the connection mode between the conductive plate and the connecting member. FIG. 16 is a diagram for explaining a modification of the monitoring device. FIG. 17 is a diagram for explaining a state in which the end portion is fitted into the groove through the insertion hole. FIG. 18 is a schematic cross-sectional view showing a state in which the temperature sensor is fixed. FIG. 19 is a diagram showing a modified example of the guide member. FIG. 20 is a diagram showing still another modification of the temperature sensor unit. FIG. 21 is a schematic perspective view showing a modified example of the power storage device. FIG. 22 is a diagram showing an example of arrangement of connecting members in the power storage device shown in FIG. FIG. 23 is a diagram showing another arrangement example of the connecting member in the power storage device shown in FIG.

[Outline of Embodiment]
The power storage device according to one aspect of the present invention is sandwiched between the first power storage module and the second power storage module stacked along the first direction, the first power storage module and the second power storage module, and the first power storage module. A conductive plate that electrically connects the second power storage module is provided adjacent to the first power storage module and the second power storage module in the second direction intersecting the first direction, and the voltage of the first power storage module and It includes a monitoring board that monitors the voltage of the second power storage module, and a connecting member for voltage monitoring that electrically connects the conductive plate and the monitoring board and extends along the second direction. Each of the first power storage module and the second power storage module includes an electrode laminate including a plurality of bipolar electrodes laminated along the first direction. The connecting member includes a first end portion connected to the conductive plate, a second end portion connected to the monitoring board, and a connecting portion connecting the first end portion and the second end portion.

In this power storage device, a monitoring board is provided for the first power storage module and the second power storage module in a direction (second direction) different from the stacking direction (first direction) of the first power storage module and the second power storage module. , The first end of the connecting member is connected to the conductive plate, and the second end of the connecting member is connected to the monitoring board, so that the conductive plate and the monitoring board are electrically connected. Therefore, it is not necessary to provide a connector on the monitoring board or the like in order to electrically connect the conductive plate and the monitoring board. As a result, the power storage device can be miniaturized.

The connecting portion may have a bent portion that bends in a direction different from the second direction. In this case, since the tensile stress applied to the connecting member is relaxed, the possibility of the connecting member breaking can be reduced.

Each of the first power storage module and the second power storage module is provided around the electrode laminate, and forms an internal space between two bipolar electrodes adjacent to each other in the first direction of the plurality of bipolar electrodes and is inside. A sealant for sealing the space and an electrolytic solution housed in the internal space may be further provided. The bent portion may have a portion that bends away from the second power storage module toward the monitoring board. The bent portion may be located between the first power storage module and the second power storage module and the monitoring board in the second direction. The electrolyte may leak from the power storage module. In such a case, when the electrolytic solution is transmitted along the connecting member and reaches the monitoring board, a short circuit (liquid junction) may occur in the monitoring board via the electrolytic solution. On the other hand, when the power storage device is arranged so that the first direction is the vertical direction (for example, the vertical direction) and the first power storage module is located above the second power storage module, the bent portion is bent. Since it is bent upward, the electrolyte is affected by gravity as it travels along the bend towards the monitoring substrate. Therefore, the electrolytic solution is suppressed from being transmitted beyond the bent portion, and may fall from the connecting member. As a result, the possibility that the electrolytic solution reaches the monitoring substrate can be reduced, and the occurrence of a short circuit can be suppressed.

The bent portion may have a convex shape protruding away from the first power storage module in the first direction. When the power storage device is arranged so that the first direction is the vertical direction (for example, the vertical direction) and the first power storage module is located above the second power storage module, the bent portion becomes convex downward. In this case, the electrolytic solution transmitted along the connecting member is likely to collect at the convex tip portion of the bent portion and fall from the bent portion. As a result, the possibility that the electrolytic solution reaches the monitoring substrate can be further reduced, and the occurrence of a short circuit can be further suppressed.

The second end extends along a plane defined by a first direction and a third direction intersecting the first and second directions, respectively, and the first and second parts facing each other in the second direction. You may have. The second end portion may be fixed to the monitoring board by sandwiching the monitoring board between the first part and the second part. In this case, the second end portion can be more firmly fixed to the monitoring board.

The conductive plate may have a first wall portion and a second wall portion facing each other, and a third wall portion connecting the first wall portion and the second wall portion. The first end may fit into a groove defined by a first wall, a second wall, and a third wall. In this case, the conductive plate and the connecting member can be connected by a simple operation of fitting the first end portion into the groove.

The first end portion may have a shape that can be elastically deformed in the direction in which the first wall portion and the second wall portion face each other. The first end portion may be held by the first wall portion and the second wall portion by the elastic force of the first end portion. In this case, since the first end portion has an elastically deformable shape, it can absorb vibration. Therefore, the stress caused by the vibration applied to the first end portion can be relaxed, and the possibility that the connection between the conductive plate and the connecting member is disconnected can be reduced.

The first end portion forms an acute angle with the extending portion extending from the connecting portion along the second direction and the extending portion, and the first inclined piece is inclined so as to approach the first wall portion toward the connecting portion. And may have. In this case, since the extending portion and the first inclined piece form an acute angle, the first end portion is compressed by simply inserting the first end portion into the groove. In this way, it is possible to improve the workability of inserting the first end portion into the groove.

The first end may further have a second sloping piece that extends from the first sloping piece towards the second wall and that slops closer to the second wall as it moves away from the first sloping piece. .. In this case, the first inclined piece and the second inclined piece form a convex shape toward the first wall portion. Therefore, when the first end portion is pulled out from the groove, the first end portion is prevented from being caught by the first wall portion, so that the first end portion can be pulled out smoothly. Therefore, it is possible to easily replace the connecting member.

A part of the second inclined piece may be located outside the groove. In this case, when the operator pushes the second inclined piece toward the second wall portion, the holding of the first end portion by the first wall portion and the second wall portion can be released. This makes it possible to easily remove the first end portion from the groove.

The above-mentioned power storage device may further include a guide member provided so as to be adjacent to the conductive plate in the second direction. The guide member may have a first end surface facing the monitoring substrate and a second end surface facing the conductive plate. The guide member may be provided with an insertion hole that penetrates the guide member along the second direction and allows the first end portion to be inserted. The insertion hole may be defined by a support surface extending along the second direction and an inclined surface that inclines so as to approach the support surface as it approaches the second end surface in the second direction. The distance between the support surface and the inclined surface on the first end surface may be larger than the distance between the first wall portion and the second wall portion. The distance between the support surface and the inclined surface on the second end surface may be smaller than the separation distance between the first wall portion and the second wall portion. In this configuration, the first end is inserted into the groove of the conductive plate through the insertion hole of the guide member. At this time, since the distance between the support surface and the inclined surface is larger than the separation distance between the first wall portion and the second wall portion at the first end surface, the guide member can be used without compressing the first end portion. The first end can be inserted into the insertion hole. Further, the inclined surface is inclined so as to approach the support surface as it approaches the second end surface in the second direction, and the distance between the support surface and the inclined surface is the first wall portion and the second wall in the second end surface. Since it is smaller than the separation distance from the portion, as the first end portion advances from the first end surface to the second end surface through the insertion hole of the guide member, the first end portion is gradually compressed and the first end portion is pushed. It is inserted into the groove in the contracted state. In this way, it is only necessary to insert the first end portion into the groove of the conductive plate through the insertion hole of the guide member, and it is possible to improve the workability of inserting the first end portion into the groove.

The guide member may be provided with an accommodation space for accommodating a temperature sensor that detects the temperature of the first power storage module. In this case, since the temperature sensor is accommodated and the insertion of the first end portion is assisted by one guide member, it is possible to suppress an increase in the number of parts.

The conductive plate may further have a protruding portion provided on the first wall portion and projecting from the first wall portion toward the second wall portion. In this configuration, when the first end tries to come out of the groove, the first end may interfere with the protrusion. Therefore, it is possible to prevent the first end portion from coming out of the groove.

The connecting member may further have a locking piece that comes into surface contact with the first wall portion in the second direction. In this case, the locking piece comes into surface contact with the first wall portion, so that the displacement of the first end portion in the groove can be regulated.

The length of the first end portion may be longer than the length of the connecting portion in the direction in which the first wall portion and the second wall portion face each other and in the direction in which the second wall portion intersects the second direction. In this case, it is possible to reduce the contact resistance, which is the electrical resistance between the first end portion and the conductive plate.

The first wall portion and the second wall portion may face each other in the first direction. In this case, the first end portion is attached between the first wall portion and the second wall portion facing each other in the first direction.

The conductive plate may be provided with a through hole for allowing the refrigerant to flow. In this case, the heat dissipation property of the conductor can be improved.

The groove may be a through hole. In this case, by using the through hole for heat dissipation, it is not necessary to provide a groove only for connecting the connecting member. Therefore, it is possible to simplify the production of the conductive plate.

The power storage device according to another aspect of the present invention is sandwiched between the first power storage module and the second power storage module stacked along the first direction, and the first power storage module and the second power storage module, and the first power storage module. The conductive plate that electrically connects the and the second power storage module is provided so as to be adjacent to the first power storage module and the second power storage module in the second direction intersecting the first direction, and the temperature of the first power storage module. A monitoring board for monitoring the above and a temperature sensor unit for detecting the temperature of the first power storage module are provided. Each of the first power storage module and the second power storage module includes an electrode laminate including a plurality of bipolar electrodes laminated along the first direction. The temperature sensor unit is provided so as to be adjacent to the first storage module in the first direction, and electrically connects the temperature sensor for detecting the temperature of the first storage module, the temperature sensor, and the monitoring board, and also in the second direction. It is provided with a connecting member extending along the line. The connecting member includes a first end portion connected to the temperature sensor, a second end portion connected to the monitoring board, and a connecting portion connecting the first end portion and the second end portion.

In this power storage device, a monitoring board is provided for the first power storage module and the second power storage module in a direction (second direction) different from the stacking direction (first direction) of the first power storage module and the second power storage module. , The first end of the connecting member is connected to the temperature sensor, and the second end of the connecting member is connected to the monitoring board, so that the temperature sensor and the monitoring board are electrically connected. Therefore, it is not necessary to provide a connector on the monitoring board or the like in order to electrically connect the temperature sensor and the monitoring board. As a result, the power storage device can be miniaturized.

The connecting portion may have a bent portion that bends in a direction different from the second direction. In this case, since the tensile stress applied to the connecting member is relaxed, the possibility of the connecting member breaking can be reduced.

Each of the first power storage module and the second power storage module is provided around the electrode laminate, and forms an internal space between two bipolar electrodes adjacent to each other in the first direction of the plurality of bipolar electrodes and is inside. A sealant for sealing the space and an electrolytic solution housed in the internal space may be further provided. The bent portion may have a portion that bends away from the second power storage module toward the monitoring board. The bent portion may be located between the first power storage module and the second power storage module and the monitoring board in the second direction. The electrolyte may leak from the power storage module. In such a case, when the electrolytic solution is transmitted along the connecting member and reaches the monitoring board, a short circuit (liquid junction) may occur in the monitoring board via the electrolytic solution. On the other hand, when the power storage device is arranged so that the first direction is the vertical direction (for example, the vertical direction) and the first power storage module is located above the second power storage module, the bent portion is bent. Since it is bent upward, the electrolyte is affected by gravity as it travels along the bend towards the monitoring substrate. Therefore, the electrolytic solution is suppressed from being transmitted beyond the bent portion, and may fall from the connecting member. As a result, the possibility that the electrolytic solution reaches the monitoring substrate can be reduced, and the occurrence of a short circuit can be suppressed.

The bent portion may have a convex shape protruding away from the first power storage module in the first direction. When the power storage device is arranged so that the first direction is the vertical direction (for example, the vertical direction) and the first power storage module is located above the second power storage module, the bent portion becomes convex downward. In this case, the electrolytic solution transmitted along the connecting member is likely to collect at the convex tip portion of the bent portion and fall from the bent portion. As a result, the possibility that the electrolytic solution reaches the monitoring substrate can be further reduced, and the occurrence of a short circuit can be further suppressed.

The second end extends along a plane defined by a first direction and a third direction intersecting the first and second directions, respectively, and the first and second parts facing each other in the second direction. You may have. The second end portion may be fixed to the monitoring board by sandwiching the monitoring board between the first part and the second part. In this case, the second end portion can be more firmly fixed to the monitoring board.

The conductive plate may have a first wall portion and a second wall portion facing each other, and a third wall portion connecting the first wall portion and the second wall portion. The temperature sensor may fit into the grooves defined by the first wall, the second wall, and the third wall. In this case, the temperature sensor can be attached by a simple operation of fitting the temperature sensor into the groove.

The first wall portion and the second wall portion may face each other in the first direction. In this case, a temperature sensor is attached between the first wall portion and the second wall portion facing each other in the first direction.

The first wall portion may come into contact with the first power storage module. The temperature sensor unit may further include an elastic member provided between the temperature sensor and the second wall portion. In this case, the elastic member presses the temperature sensor against the first wall portion. Therefore, the temperature sensor is firmly fixed to the first wall portion. This makes it possible to improve the temperature detection accuracy of the first power storage module.

The above-mentioned power storage device may be provided adjacent to the conductive plate in the second direction, and may further include a holding member for holding the temperature sensor. In this case, since it is not necessary to provide a groove in the conductive plate, the structure of the conductive plate can be simplified.

The holding member may have a support surface that faces the first power storage module and supports the temperature sensor. The support surface may define an accommodation space for accommodating the temperature sensor. In this case, the temperature sensor can be positioned by accommodating the temperature sensor in the accommodation space.

The holding member may further have an inclined surface that is continuous with the support surface in the second direction. The inclined surface may be inclined so that the distance from the first power storage module increases as the distance from the support surface increases. In this case, the inclined surface can function as a guide when accommodating the temperature sensor in the accommodating space. Therefore, it is possible to improve the workability of accommodating the temperature sensor in the accommodating space.

The temperature sensor unit may further include an elastic member provided between the temperature sensor and the support surface. In this case, the elastic member presses the temperature sensor toward the first power storage module. This makes it possible to improve the temperature detection accuracy of the first power storage module.

The conductive plate may be provided with a through hole for allowing the refrigerant to flow. In this case, the heat dissipation property of the conductor can be improved.

The power storage device according to still another aspect of the present invention includes a plurality of power storage modules stacked along the first direction, and a first power storage module and a second power storage module that are adjacent to each other in the first direction among the plurality of power storage modules. A first conductive plate sandwiched between the power storage modules and electrically connecting the first power storage module and the second power storage module, and adjacent to the first conductive plate via the second power storage module in the first direction. A second conductive plate provided and electrically connected to the second power storage module, and a first voltage monitoring plate connected to the first conductive plate and extending along the second direction intersecting the first direction. A connecting member, a second connecting member for voltage monitoring which is connected to the second conductive plate and extends along the second direction, and a second connecting member which is provided adjacent to a plurality of power storage modules in the second direction. It is provided with a fixing portion for fixing the first connecting member and the second connecting member. Each of the plurality of power storage modules is provided around the electrode laminate including the plurality of bipolar electrodes laminated along the first direction, and adjacent to each other in the first direction of the plurality of bipolar electrodes. It includes a sealant for forming an internal space between two matching bipolar electrodes and sealing the internal space, and an electrolytic solution housed in the internal space. The first connecting member and the second connecting member are separated in a third direction intersecting the first direction and the second direction.

In this power storage device, a fixing portion is provided for a plurality of power storage modules in a direction (second direction) different from the stacking direction (first direction) of the plurality of power storage modules, and is connected to the first conductive plate. The first connecting member and the second connecting member connected to the second conductive plate are fixed to the fixing portion. The first connecting member and the second connecting member are separated from each other in the third direction. When the power storage device is arranged so that the first direction is the vertical direction (for example, the vertical direction) and the first power storage module is located above the second power storage module, the first connection member is the second. It is located above the connecting member. In this case, even if the electrolytic solution leaked from the power storage module reaches the fixed portion along the first connecting member and drops due to gravity at the fixed portion, the first connecting member and the second connecting member keep the electrolytic solution. It is possible to reduce the possibility of short circuit through. As a result, it becomes possible to improve the reliability of the power storage device.

The above-mentioned power storage device is provided between the third power storage module and the fourth power storage module that are adjacent to each other in the first direction among the plurality of power storage modules, and electrically connects the third power storage module and the fourth power storage module. A third conductive plate connected to the third conductive plate and a third connecting member for voltage monitoring connected to the third conductive plate and extending along the second direction may be further provided. The fixing portion may further fix the third connecting member. The first connecting member, the second connecting member, and the third connecting member may be arranged in that order in the first direction. The first connecting member and the third connecting member may overlap each other when viewed from the first direction. In this configuration, at least a second connecting member is arranged between the first connecting member and the third connecting member in the first direction. Therefore, the distance between the first connecting member and the third connecting member in the first direction is larger than that in the configuration in which the first connecting member and the third connecting member are adjacent to each other in the first direction. When the power storage device is arranged so that the first direction is the vertical direction (for example, the vertical direction) and the first power storage module is located above the second power storage module, the first connection member is the third. It is located above the connecting member. In this case, even if the electrolytic solution that has reached the fixed portion along the first connecting member drops due to gravity, the first connecting member and the third connecting member are separated from each other, so that the first connecting member and the third connecting member are separated. It is possible to reduce the possibility of short-circuiting with and through the electrolytic solution.

The first connecting member may have a bent portion that bends away from the second connecting member toward the fixed portion. The bent portion may be located between the plurality of power storage modules and the fixed portion in the second direction. When the power storage device is arranged so that the first direction is the vertical direction (for example, the vertical direction) and the first power storage module is located above the second power storage module, the first connection member is the second. It is located above the connecting member. Therefore, since the bent portion is bent upward, the electrolytic solution is affected by gravity when the electrolytic solution is transmitted toward the fixed portion along the bent portion. Therefore, it is suppressed that the electrolytic solution is transmitted beyond the bent portion, and the electrolytic solution may fall from the first connecting member. As a result, the possibility that the electrolytic solution reaches the fixed portion can be reduced, and the occurrence of a short circuit can be further suppressed.

The above-mentioned power storage device may further include a monitoring board for monitoring the voltages of a plurality of power storage modules. The fixing portion may be a monitoring board. In this case, in the monitoring board, the possibility that the first connecting member and the second connecting member are short-circuited via the electrolytic solution can be reduced.

[Details of Embodiment]
Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings. In the description of the drawings, the same reference numerals are used for the same or equivalent elements, and duplicate description is omitted.

FIG. 1 is a schematic perspective view showing a power storage device according to an embodiment. FIG. 2 is a schematic cross-sectional view taken along line II-II of FIG. The power storage device 1 shown in FIGS. 1 and 2 is used as a battery for various vehicles such as forklifts, hybrid vehicles, and electric vehicles. The power storage device 1 includes a module laminate 2, a restraint member 3, and a monitoring device 50.

The module laminate 2 includes a plurality of (five in this embodiment) power storage modules 4 and a plurality of (six in this embodiment) conductive plates 5. The plurality of power storage modules 4 are stacked (arranged) along the stacking direction D1 (first direction). The power storage module 4 is a bipolar battery and has a rectangular shape when viewed from the stacking direction D1. The power storage module 4 is, for example, a secondary battery such as a nickel hydrogen secondary battery and a lithium ion secondary battery, or an electric double layer capacitor. In the following description, a nickel hydrogen secondary battery will be illustrated.

Two power storage modules 4 adjacent to each other in the stacking direction D1 sandwich a conductive plate 5 and are electrically connected to each other via the conductive plate 5. The conductive plates 5 are arranged between two power storage modules 4 adjacent to each other in the stacking direction D1 and on the outer surface of the power storage modules 4 located at the stacking ends. The positive electrode terminal 6 is connected to the conductive plate 5 arranged on the outer surface of the power storage module 4 located at the lower end of the stack. The negative electrode terminal 7 is connected to the conductive plate 5 arranged on the outer surface of the power storage module 4 located at the upper end of the stack. The positive electrode terminal 6 and the negative electrode terminal 7 are drawn out from the edge of the conductive plate 5 in the direction D2 (second direction) intersecting (orthogonal) with the stacking direction D1. The positive electrode terminal 6 and the negative electrode terminal 7 charge and discharge the power storage device 1.

The conductive plate 5 is provided with a plurality of flow paths 5a and a plurality of (two in the present embodiment) grooves 5b. The flow path 5a is a through hole for passing a refrigerant such as air. The flow path 5a penetrates the conductive plate 5 in the direction D3 (third direction) intersecting (orthogonal) with the stacking direction D1 and the direction D2, respectively, and extends along the direction D3. The plurality of flow paths 5a are arranged along the direction D2. Grooves 5b are provided at both ends of the conductive plate 5 in the direction D2. The number of grooves 5b may be one, and in this case, the grooves 5b are provided only at one end on the monitoring board 51 side. The groove 5b penetrates the conductive plate 5 in the direction D3, and extends along the direction D3, for example. The conductive plate 5 at the upper end of the lamination and the conductive plate 5 at the lower end of the lamination may not be provided with the flow path 5a.

The conductive plate 5 connects the wall portion 5c (first wall portion; see FIG. 4) and the wall portion 5d (second wall portion; see FIG. 4) facing each other in the stacking direction D1, and the wall portion 5c and the wall portion 5d. It is provided with a plurality of partition walls 5e (third wall portion; see FIG. 4). The partition wall 5e is erected between the wall portion 5c and the wall portion 5d. A plurality of flow paths 5a and a plurality of grooves 5b are defined by the wall portion 5c, the wall portion 5d, and the plurality of partition walls 5e.

The conductive plate 5 has a function as a connecting member for electrically connecting two power storage modules 4 adjacent to each other in the stacking direction D1, and also a power storage module by circulating a refrigerant through these flow paths 5a and grooves 5b. It also has a function as a heat radiating plate that releases the heat generated in 4. In the examples of FIGS. 1 and 2, the area of the conductive plate 5 seen from the stacking direction D1 is smaller than the area of the power storage module 4, but from the viewpoint of improving heat dissipation, the area of the conductive plate 5 is stored. It may be the same as the area of the module 4, or may be larger than the area of the power storage module 4.

The restraint member 3 is a member that applies a restraint load to the module laminate 2 in the stacking direction D1 of the module laminate 2. The restraint member 3 includes a pair of end plates 8 that sandwich the module laminate 2 in the stacking direction D1, and a fastening bolt 9 and a nut 10 that fasten the pair of end plates 8 to each other. The end plate 8 is a rectangular metal plate having an area one size larger than the area of the power storage module 4 and the conductive plate 5 as viewed from the stacking direction D1. An insulating plate F having electrical insulation is provided on the inner surface of the end plate 8. The insulating plate F insulates between the end plate 8 and the conductive plate 5.

An insertion hole 8a is provided at the edge of the end plate 8 at a position outside the module laminate 2. The fastening bolt 9 is passed from the insertion hole 8a of one end plate 8 toward the insertion hole 8a of the other end plate 8, and is attached to the tip portion of the fastening bolt 9 protruding from the insertion hole 8a of the other end plate 8. , The nut 10 is screwed. As a result, the power storage module 4 and the conductive plate 5 are sandwiched by the pair of end plates 8 to be unitized as the module laminate 2, and a restraining load is applied to the module laminate 2 in the stacking direction D1.

The monitoring device 50 is a device that monitors the module laminate 2. For example, the monitoring device 50 monitors the status of the plurality of power storage modules 4. Details of the monitoring device 50 will be described later.

Next, the configuration of the power storage module 4 will be described in detail. FIG. 3 is a schematic cross-sectional view showing the internal configuration of the power storage module shown in FIG. As shown in FIG. 3, each of the plurality of power storage modules 4 includes an electrode laminated body 11 and a sealing body 12 that seals the electrode laminated body 11. The electrode laminate 11 has a plurality of separators 13, a plurality of bipolar electrodes 14, a negative electrode terminal electrode 18, and a positive electrode terminal electrode 19. In the present embodiment, the stacking direction of the electrode laminated body 11 coincides with the stacking direction D1 of the module laminated body 2. The electrode laminate 11 has a side surface 11a extending in the lamination direction D1.

The separator 13 is formed in a sheet shape, for example. Examples of the separator 13 include a porous film made of a polyolefin resin such as polyethylene (PE) and polypropylene (PP), and a woven fabric or a non-woven fabric made of polypropylene, methyl cellulose and the like. The separator 13 may be reinforced with a vinylidene fluoride resin compound. The separator 13 may have a bag shape.

The negative electrode terminal electrode 18, the plurality of bipolar electrodes 14, and the positive electrode terminal electrodes 19 (plurality of electrodes) are laminated in this order via the separator 13 along the stacking direction D1. Each of the plurality of bipolar electrodes 14 includes an electrode plate 15, a positive electrode 16, and a negative electrode 17. The electrode plate 15 is made of, for example, a metal foil made of nickel or a nickel-plated steel plate, and has a rectangular shape. The electrode plate 15 includes an upper surface 15a and a lower surface 15b opposite to the upper surface 15a. The peripheral edge portion 15c of the electrode plate 15 is an uncoated region in which the positive electrode active material and the negative electrode active material are not coated.

The positive electrode 16 is provided on the upper surface 15a of the electrode plate 15. The positive electrode 16 is a positive electrode active material layer formed by applying a positive electrode active material to the upper surface 15a. Examples of the positive electrode active material constituting the positive electrode 16 include nickel hydroxide. The negative electrode 17 is provided on the lower surface 15b of the electrode plate 15. The negative electrode 17 is a negative electrode active material layer formed by applying a negative electrode active material to the lower surface 15b. Examples of the negative electrode active material constituting the negative electrode 17 include a hydrogen storage alloy. In the present embodiment, the formation region of the negative electrode 17 on the lower surface 15b of the electrode plate 15 is one size larger than the formation region of the positive electrode 16 on the upper surface 15a of the electrode plate 15.

In the electrode laminate 11, the positive electrode 16 of one bipolar electrode 14 faces the negative electrode 17 of one of the bipolar electrodes 14 adjacent to the stacking direction D1 with the separator 13 interposed therebetween. In the electrode laminate 11, the negative electrode 17 of one bipolar electrode 14 faces the positive electrode 16 of the other bipolar electrode 14 adjacent to the stacking direction D1 with the separator 13 interposed therebetween.

The negative electrode terminal electrode 18 is arranged at one end 11b of the electrode laminate 11 in the stacking direction D1. The negative electrode terminal electrode 18 includes an electrode plate 15 and a negative electrode 17 provided on the lower surface 15b of the electrode plate 15. The negative electrode 17 of the negative electrode terminal electrode 18 faces the positive electrode 16 of the bipolar electrode 14 located at one end in the stacking direction D1 via the separator 13. One of the conductive plates 5 adjacent to the power storage module 4 is in contact with the upper surface 15a of the electrode plate 15 of the negative electrode terminal electrode 18.

The positive electrode terminal electrode 19 is arranged at the other end 11c on the side opposite to one end 11b of the electrode laminate 11 in the stacking direction D1. The positive electrode terminal electrode 19 includes an electrode plate 15 and a positive electrode 16 provided on the upper surface 15a of the electrode plate 15. The positive electrode 16 of the positive electrode terminal electrode 19 faces the negative electrode 17 of the bipolar electrode 14 located at the other end of the stacking direction D1 via the separator 13. The other conductive plate 5 adjacent to the power storage module 4 is in contact with the lower surface 15b of the electrode plate 15 of the positive electrode terminal electrode 19.

The sealing body 12 is formed in a rectangular tubular shape, for example. The sealing body 12 is formed of a resin material having an insulating property. Examples of the resin material constituting the sealing body 12 include polypropylene (PP), polyphenylene sulfide (PPS), modified polyphenylene ether (modified PPE), and the like. The sealing body 12 is provided around the electrode laminated body 11, forms an internal space V in the electrode laminated body 11, and seals the internal space V. Specifically, the sealing body 12 is configured to hold the peripheral edge portion 15c of the electrode plate 15 on the side surface 11a of the electrode laminated body 11 extending in the stacking direction D1 and to surround the side surface 11a. The sealing body 12 seals between two bipolar electrodes 14 adjacent to each other in the stacking direction D1.

The sealing body 12 has a plurality of primary sealing bodies 21 and a secondary sealing body 22. The primary sealing body 21 is continuously provided over the entire circumference (all sides) of the electrode plate 15 at the peripheral edge portion 15c (uncoated region) of the electrode plate 15. The secondary sealing body 22 is provided so as to surround the plurality of primary sealing bodies 21 from the outside. The secondary sealing body 22 is provided around the electrode laminated body 11 and the plurality of primary sealing bodies 21, and constitutes an outer wall (housing) of the power storage module 4. The secondary sealing body 22 is formed by injection molding of a resin, and extends along the stacking direction D1 over the entire length of the electrode laminated body 11. The secondary sealing body 22 has a tubular shape (annular shape) extending in the axial direction in the stacking direction D1. The secondary encapsulant 22 is welded (bonded) to, for example, the end face of the primary encapsulant 21 on the outer edge side by heat during injection molding.

The secondary encapsulant 22, together with the primary encapsulant 21, is between two bipolar electrodes 14 adjacent to each other in the stacking direction D1, between the negative electrode termination electrodes 18 and the bipolar electrodes 14 adjacent to each other in the stacking direction D1, and , The positive electrode terminal 19 and the bipolar electrode 14 adjacent to each other in the stacking direction D1 are sealed. As a result, an airtightly partitioned internal space V is formed between the two bipolar electrodes 14, between the negative electrode termination electrode 18 and the bipolar electrode 14, and between the positive electrode termination electrode 19 and the bipolar electrode 14. Has been done. Each internal space V contains an electrolytic solution (not shown) composed of an alkaline aqueous solution such as an aqueous potassium hydroxide solution. The electrolytic solution is impregnated in the separator 13, the positive electrode 16 and the negative electrode 17.

Next, the configuration of the monitoring device 50 will be described in detail with reference to FIGS. 4 to 7. FIG. 4 is an enlarged view of a part of the cross section shown in FIG. FIG. 5 is a schematic perspective view showing the connecting member shown in FIG. FIG. 6 is an enlarged view of a part of the cross section along the VI-VI line of FIG. FIG. 7 is a diagram for explaining a method of connecting the connecting member and the temperature sensor unit. 4 and 6 show two power storage modules 4 adjacent to each other in the stacking direction D1 and a conductive plate 5 (first conductive plate) sandwiched between the two power storage modules 4. For convenience of explanation, of the two power storage modules 4, the power storage module 4 (first power storage module) located on the upper side is referred to as "power storage module 4A", and the power storage module 4 (second power storage module) located on the lower side is referred to as "power storage module 4A". It may be referred to as "storage module 4B".

The monitoring device 50 includes a monitoring board 51, a plurality of (six in this embodiment) connecting members 52, and a plurality of (three in this embodiment) temperature sensor units 53.

The monitoring board 51 is a circuit board for monitoring the state of a plurality of power storage modules 4. The monitoring board 51 monitors, for example, the terminal voltage and temperature of each power storage module 4. The terminal voltage is a voltage between the positive electrode terminal electrode 19 and the negative electrode terminal electrode 18, and is a potential difference between the potential of the positive electrode terminal electrode 19 and the potential of the negative electrode terminal electrode 18. In the present embodiment, the monitoring board 51 has the temperature of the power storage module 4 located at the upper end of the stack, the temperature of the power storage module 4 located at the lower end of the stack, and the temperature of the power storage module 4 located in the middle of the module stack 2. To monitor.

The monitoring board 51 includes a wiring board portion and circuit components mounted on the wiring board portion. Examples of circuit components mounted on the wiring board include a voltage monitoring IC (Integrated Circuit), a CPU (Central Processing Unit), and a capacitor. The voltage monitoring IC receives the potential of the positive electrode terminal 19 and the potential of the negative electrode 18 of each power storage module 4 via each of the plurality of connection members 52, and outputs a signal regarding the terminal voltage of the power storage module 4 to the CPU. To do. The CPU receives a signal regarding the temperature of each power storage module 4 from the temperature sensor unit 53. The CPU transmits a signal related to temperature and a signal related to terminal voltage to a higher-level ECU (Electronic Control Unit) which is an external device.

The monitoring board 51 is provided so as to be adjacent to the module laminate 2 in the direction D2. Specifically, the monitoring board 51 is provided along the side surface 2a of the module laminate 2. The side surface 2a is a surface extending along the stacking direction D1 and the direction D3. The monitoring board 51 has a surface 51a facing the side surface 2a and a surface 51b opposite to the surface 51a. The monitoring board 51 is provided with a plurality of through holes 51c and a plurality of through holes 51d. The through holes 51c and 51d are holes that penetrate the monitoring substrate 51 along the direction D2. The through hole 51c is used for inserting the end portion 56 of the connecting member 52 described later. The through hole 51d is used for inserting the end portion 62 of the connecting member 60 described later. The monitoring board 51 is fixed to the pair of end plates 8 by fixing members 54 such as bolts.

Each of the plurality of connecting members 52 is a member for voltage monitoring and is a metal conductive member extending along the direction D2. Each of the plurality of connecting members 52 is provided on different conductive plates 5, and electrically connects the conductive plate 5 provided with the connecting members 52 and the monitoring board 51. Each connecting member 52 transmits the potential of the conductive plate 5 corresponding to the connecting member 52 to the monitoring board 51. In the example of FIG. 4, since the conductive plate 5 is in contact with the positive electrode terminal 19 of the power storage module 4A and the negative electrode terminal 18 of the power storage module 4B, the potential of the conductive plate 5 is the potential of the positive electrode 19 of the power storage module 4A. And equal to the potential of the negative electrode terminal 18 of the power storage module 4B. In this way, the potential of the positive electrode terminal 19 and the potential of the negative electrode 18 of each storage module 4 are transmitted to the monitoring board 51 by the plurality of connecting members 52.

The connecting member 52 includes an end portion 55 (first end portion), an end portion 56 (second end portion), and a connecting portion 57. The end portion 55 is a portion connected to the conductive plate 5. The end 55 is directly connected to the conductive plate 5 without the need for other components such as wire harnesses and connectors. The end portion 55 has a shape that fits into the groove 5b. More specifically, the end portion 55 has a shape that can be elastically deformed in the direction in which the wall portion 5c and the wall portion 5d face each other (stacking direction D1). The end portion 55 is inserted into the groove 5b in a state of being compressed in the stacking direction D1, and the elastic force of the end portion 55 presses each of the wall portion 5c and the wall portion 5d. As a result, the end portion 55 is held by the wall portion 5c and the wall portion 5d. In order to further increase the holding strength, the end portion 55 may be bonded to at least one of the wall portion 5c and the wall portion 5d by ultrasonic welding, resistance welding or the like.

In the present embodiment, the end portion 55 has an extending portion 55a and an inclined piece 55b (first inclined piece). The extending portion 55a is a portion extending from the connecting portion 57 along the direction D2 in the direction opposite to the end portion 56. That is, one end of the extending portion 55a is connected to one end of the connecting portion 57. The extending portion 55a extends along the inner surface of the wall portion 5d with the end portion 55 fitted into the groove 5b. The inclined piece 55b is a portion that is folded upward and extends from the other end of the extending portion 55a. That is, one end of the inclined piece 55b is connected to the other end of the extending portion 55a. With the end portion 55 fitted in the groove 5b, the inclined piece 55b is inclined so as to approach the wall portion 5c toward the connecting portion 57. The inclined piece 55b forms an acute angle with the extending portion 55a.

In the state where the end portion 55 is not fitted in the groove 5b, the distance between the other end of the inclined piece 55b and the extending portion 55a in the stacking direction D1 is larger than the separation distance between the wall portion 5c and the wall portion 5d. In the state where the end portion 55 is fitted into the groove 5b, the distance between the other end of the inclined piece 55b and the extending portion 55a in the stacking direction D1 is shortened by the wall portion 5c and the wall portion 5d. As a result, the extending portion 55a and the inclined piece 55b function as leaf springs and elastically deform in the stacking direction D1.

The end portion 56 is a portion connected to the monitoring board 51. The end 56 is directly connected to the monitoring board 51 without the need for other components such as wire harnesses and connectors. One end of the end portion 56 is connected to the other end of the connecting portion 57, and the other end of the end portion 56 is fixed to the monitoring board 51. The end portion 56 is inserted through the through hole 51c from the surface 51a to the surface 51b, and is connected (joined) to the monitoring board 51 by soldering, a press-fit structure, screw (bolt) fastening, or the like.

The connecting portion 57 is a portion that connects the end portion 55 and the end portion 56. The connecting portion 57 has a bent portion 58. The bent portion 58 is bent in a direction different from the direction D2 from the viewpoint of stress relaxation. The bent portion 58 may include a portion that bends so that a portion closer to the end portion 56 is located above the portion closer to the end portion 55 from the viewpoint of preventing a short circuit due to liquid leakage. In other words, the bent portion 58 may include a portion that bends away from the power storage module 4B in the stacking direction D1 toward the monitoring substrate 51. In the present embodiment, the bent portion 58 has a convex shape protruding downward. The bent portion 58 is formed by bending the connecting portion 57 in a V shape so as to project downward. The bent portion 58 is located between the module laminate 2 and the monitoring board 51 in the direction D2. In this embodiment, the bent portions 58 of the plurality of connecting members 52 are bent in the same direction.

In the direction in which the wall portion 5c and the wall portion 5d face each other (stacking direction D1) and in the direction intersecting the direction D2 (direction D3), the length of the end portion 55 (width W1) is the length of the end portion 56 (width W2). ) And the length of the connecting portion 57 (width W3). The width W2 is about the same as the width W3. The end portion 55, the end portion 56, and the connecting portion 57 are integrally formed. For example, the connecting member 52 is formed by bending a base material obtained by punching a metal plate into a predetermined shape.

The temperature sensor unit 53 is a unit for detecting the temperature of the power storage module 4. In the present embodiment, the power storage module 4 to be detected is a power storage module 4 located at the upper end of the stack, a power storage module 4 located at the lower end of the stack, and a power storage module 4 located at the center of the stack, and the temperature of these power storage modules 4 Three temperature sensor units 53 are provided to detect the above.

The temperature sensor unit 53 includes a temperature sensor 59 and a connecting member 60. The temperature sensor 59 detects the temperature of the power storage module 4 to be detected. An example of a temperature sensor is a thermistor element. The temperature sensor 59 is provided so as to be adjacent to the power storage module 4 to be detected in the stacking direction D1. The temperature sensor 59 may or may not be in contact with the power storage module 4 to be detected. In this embodiment, the temperature sensor 59 fits into the groove 5b. In the example of FIG. 6, the power storage module 4A is the power storage module 4 to be detected, and the temperature sensor 59 fits into the groove 5b of the conductive plate 5 sandwiched between the power storage module 4A and the power storage module 4B. The temperature sensor 59 detects the temperature of the power storage module 4 (power storage module 4A) to be detected via the wall portion 5c that is in contact with the power storage module 4 to be detected.

The connecting member 60 is a temperature monitoring member and is a metal conductive member extending along the direction D2. The connecting member 60 is, for example, a lead wire extending from the temperature sensor 59. The connecting member 60 electrically connects the temperature sensor 59 and the monitoring board 51. The connecting member 60 transmits a signal regarding the temperature of the power storage module 4 to be detected to the monitoring board 51.

The connecting member 60 includes an end portion 61 (first end portion), an end portion 62 (second end portion), and a connecting portion 63. The end portion 61 is a portion connected to the temperature sensor 59. The end 61 is directly connected to the temperature sensor 59 without the need for other components such as wire harnesses and connectors. The end portion 61 is connected (joined) to the temperature sensor 59 by solder or the like. The end portion 62 is a portion connected to the monitoring board 51. The end 62 is directly connected to the monitoring board 51 without the need for other components such as wire harnesses and connectors. The end portion 62 is inserted through the through hole 51d from the surface 51a to the surface 51b, and is connected (joined) to the monitoring board 51 by soldering, a press-fit structure, screw (bolt) fastening, or the like.

The connecting portion 63 is a portion that connects the end portion 61 and the end portion 62. The connecting portion 63 has a bent portion 64. The bent portion 64 is bent in a direction different from the direction D2 from the viewpoint of stress relaxation. The bent portion 64 may include a portion that bends so that a portion closer to the end portion 62 is located above the portion closer to the end portion 61 from the viewpoint of preventing a short circuit due to liquid leakage. In other words, the bent portion 64 may include a portion that bends away from the power storage module 4B in the stacking direction D1 toward the monitoring substrate 51. In the present embodiment, the bent portion 64 has a convex shape protruding downward, similarly to the bent portion 58. The bent portion 64 is formed by bending the connecting portion 63 in a V shape so as to project downward. The bent portion 64 is located between the module laminate 2 and the monitoring board 51. In the present embodiment, the bent portions 64 of the plurality of connecting members 60 are bent in the same direction.

The end portion 61, the end portion 62, and the connecting portion 63 are integrally formed. For example, the connecting member 60 is formed by bending the lead wire extending from the temperature sensor 59.

As described above, in the power storage device 1, the monitoring board 51 is provided in the direction (direction D2) different from the stacking direction D1 of the module stacking body 2 with respect to the module stacking body 2. The conductive plate 5 and the monitoring board 51 are electrically connected by connecting the end 55 of the connecting member 52 to the conductive plate 5 and connecting the end 56 of the connecting member 52 to the monitoring board 51. Therefore, it is not necessary to provide the connector on the module laminate 2 and the monitoring board 51 in order to electrically connect the conductive plate 5 and the monitoring board 51. As a result, the power storage device 1 can be miniaturized.

Similarly, the temperature sensor 59 and the monitoring board 51 are electrically connected by connecting the end 61 of the connecting member 60 to the temperature sensor 59 and connecting the end 62 of the connecting member 60 to the monitoring board 51. To. Therefore, it is not necessary to provide a connector on the module laminate 2 and the monitoring board 51 in order to electrically connect the temperature sensor 59 and the monitoring board 51. As a result, the power storage device 1 can be miniaturized.

The connecting portion 57 of the connecting member 52 has a bent portion 58. Similarly, the connecting portion 63 of the connecting member 60 has a bent portion 64. Since the bent portions 58 and 64 are bent in a direction different from the direction D2, the tensile stress applied to the connecting members 52 and 60 is relaxed by the bent portions 58 and 64. This makes it possible to reduce the possibility that the connecting members 52 and 60 will break.

The electrolytic solution may leak from the power storage module 4. In such a case, when the electrolytic solution is transmitted along the connecting members 52 and 60 and reaches the monitoring board 51, a short circuit (liquid entanglement) may occur in the monitoring board 51 via the electrolytic solution. For example, if the two connecting members 52 are short-circuited via the electrolytic solution, the accuracy of detecting the terminal voltage may decrease. Further, if the two connecting members 60 are short-circuited via the electrolytic solution, the temperature detection accuracy of the power storage module 4 may decrease. On the other hand, the bent portions 58 and 64 have a portion that bends away from the power storage module 4B toward the monitoring board 51. Further, the bent portions 58 and 64 are located between the module laminate 2 and the monitoring board 51 in the direction D2. When the power storage device 1 is arranged and used so that the stacking direction D1 is in the vertical direction (for example, the vertical direction) and the power storage module 4A is located above the power storage module 4B, the bent portions 58 and 64 are used. However, it will have a portion that bends upward toward the monitoring board 51. Therefore, when the electrolytic solution is transmitted toward the monitoring substrate 51 along the bent portions 58 and 64, the electrolytic solution is affected by gravity. Therefore, the electrolytic solution is suppressed from being transmitted beyond the bent portions 58 and 64, and may fall from the connecting members 52 and 60. As a result, the possibility that the electrolytic solution reaches the monitoring board 51 can be reduced, and the occurrence of a short circuit can be suppressed.

In the above embodiment, the bent portions 58 and 64 have a convex shape protruding away from the power storage module 4A along the stacking direction D1. When the power storage device 1 is arranged and used so that the stacking direction D1 is in the vertical direction (for example, the vertical direction) and the power storage module 4A is located above the power storage module 4B, the bent portions 58 and 64 are used. Is convex downward. In this case, the electrolytic solution transmitted along the connecting members 52 and 60 gathers at the convex tip portions of the bent portions 58 and 64, and the possibility of falling from the bent portions 58 and 64 increases. As a result, the possibility that the electrolytic solution reaches the monitoring board 51 can be reduced, and the occurrence of a short circuit can be suppressed.

An end portion 55 and a temperature sensor 59 are attached between the wall portions 5c and the wall portions 5d facing each other in the stacking direction D1.

Specifically, the end portion 55 of the connecting member 52 fits into the groove 5b of the conductive plate 5. In this way, the conductive plate 5 and the connecting member 52 can be connected by a simple operation of fitting the end portion 55 into the groove 5b. Similarly, the temperature sensor 59 fits into the groove 5b of the conductive plate 5. In this way, the temperature sensor 59 can be attached by a simple operation of fitting the temperature sensor 59 into the groove 5b.

Since the end portion 55 has a shape that can be elastically deformed in the direction in which the wall portion 5c and the wall portion 5d face each other (stacking direction D1), the end portion 55 can absorb vibration. Therefore, even if the stress caused by the vibration is applied to the end portion 55, the stress can be relaxed, so that the possibility that the connection between the conductive plate 5 and the connecting member 52 is disconnected can be reduced. It becomes.

Specifically, the end portion 55 forms an acute angle with the extending portion 55a extending from the connecting portion 57 along the direction D2 and the extending portion 55a so as to approach the wall portion 5c toward the connecting portion 57. It has an acute-angled piece 55b and an inclined piece 55b. Since the extending portion 55a and the inclined piece 55b form an acute angle in this way, the work of inserting the end portion 55 into the groove 5b can be simplified. Further, in a state where the connecting member 52 is not connected to the conductive plate 5, the stacking direction D1 between the other end of the inclined piece 55b (the end opposite to the end connected to the extending portion 55a) and the extending portion 55a. Is larger than the distance between the wall portion 5c and the wall portion 5d. Therefore, as the end portion 55 is inserted into the groove 5b, the distance between the other end of the inclined piece 55b and the extending portion 55a in the stacking direction D1 is reduced by the wall portion 5c and the wall portion 5d. As a result, the elastic force of the end portion 55 acts on the wall portion 5c and the wall portion 5d, and the end portion 55 is held by the elastic force of the end portion 55 on the wall portion 5c and the wall portion 5d.

The width W1 of the end portion 55 is larger than the width W3 of the connecting portion 57. Therefore, the contact area between the end portion 55 and the conductive plate 5 (groove 5b) can be increased as compared with the case where the width W1 of the end portion 55 is the same as the width W3 of the connecting portion 57. This makes it possible to reduce the contact resistance, which is the electrical resistance between the end portion 55 and the conductive plate 5.

Since the conductive plate 5 is provided with a flow path 5a and a groove 5b for allowing the refrigerant to flow, the heat dissipation of the conductive plate 5 can be improved.

Although one embodiment of the present invention has been described in detail above, the present invention is not limited to the above embodiment.

For example, the number of stacks of the power storage modules 4 included in the module stack 2 can be changed as appropriate. The module laminate 2 is sandwiched between two power storage modules 4 stacked along the stacking direction D1 and the power storage modules 4 in the stacking direction D1, and is a conductive plate that electrically connects these power storage modules 4. It suffices to have 5.

The plurality of power storage modules 4 may be connected in parallel. The conductive plate 5 may not be provided with the flow path 5a.

The monitoring device 50 may include at least one of a connecting member 52 and a temperature sensor unit 53 (connecting member 60). For example, the monitoring device 50 may include a signal line composed of a wire harness instead of either the connecting member 52 or the connecting member 60. Further, the connecting portion 57 may not have the bent portion 58, and the connecting portion 63 may not have the bent portion 64.

As described above, the monitoring board 51 functions as a fixing portion for fixing the plurality of connecting members 52 and the plurality of connecting members 60. The power storage device 1 may include another fixing portion for fixing the plurality of connecting members 52 and the plurality of connecting members 60 between the monitoring board 51 and the module laminate 2. Another fixing portion is provided so as to be adjacent to the module laminate 2 in the direction D2. As another fixing portion, for example, a case where the monitoring board 51 is housed can be mentioned.

The shape of the end portion 55 is not limited to the shape of the end portion 55 of the above embodiment. The connection mode between the end portion 55 and the conductive plate 5 is not limited to the connection mode of the above embodiment. For example, as shown in (a) of FIG. 8 and (b) of FIG. 8, the end portion 55 may further have an inclined piece 55c (second inclined piece). The inclined piece 55c is a portion that is bent downward and extends from the other end of the inclined piece 55b. That is, one end of the inclined piece 55c is connected to the other end of the inclined piece 55b. The inclined piece 55c extends from the inclined piece 55b toward the wall portion 5d, and is inclined so as to approach the connecting portion 57 as the distance from the inclined piece 55b increases. The inclined piece 55c has an obtuse angle with the inclined piece 55b, and the inclined piece 55b and the inclined piece 55c exhibit a convex shape toward the wall portion 5c. A part of the inclined piece 55c including the other end is located outside the groove 5b.

In the power storage device 1 of the above embodiment, when the end portion 55 is pulled out from the groove 5b, the other end of the inclined piece 55b may be caught by the wall portion 5c. On the other hand, in the configurations shown in FIGS. 8A and 8B, the inclined piece 55b and the inclined piece 55c have a convex shape toward the wall portion 5c. Therefore, when the end portion 55 is pulled out from the groove 5b, the end portion 55 is prevented from being caught by the wall portion 5c, so that the end portion 55 can be pulled out smoothly. Therefore, the replacement work of the connecting member 52 can be easily performed.

A part of the inclined piece 55c is located outside the groove 5b. Therefore, as shown in FIG. 8B, the operator picks the exposed portion of the inclined piece 55c and the connecting portion 57 so that the inclined piece 55c and the connecting portion 57 approach each other. The end portion 55 can be compressed in the stacking direction D1, and the end portion 55 can be easily pulled out from the groove 5b.

As shown in FIGS. 8A and 8B, the end portion 55 is formed between the extending portion 55a and the inclined piece 55b, the other end of the extending portion 55a and one end of the inclined piece 55b. May further have a connecting piece 55d for connecting the above. The connecting piece 55d extends along the partition wall 5e. Therefore, even if the end portion 55 is inserted into the groove 5b until it abuts on the partition wall 5e, the connecting piece 55d abuts on the partition wall 5e, so that damage to the partition wall 5e is reduced.

As shown in FIG. 9, the conductive plate 5 may further have a protrusion 5f. The protruding portion 5f is provided on the wall portion 5c and projects from the wall portion 5c toward the wall portion 5d. The protruding portion 5f is formed by, for example, bending the end portion of the wall portion 5c toward the wall portion 5d. In this configuration, when the end 55 tries to come out of the groove 5b due to vibration or the like, the end 55 may interfere with the protrusion 5f in the direction D2. Therefore, it is possible to prevent the end portion 55 from coming out of the groove 5b. For example, even when the power storage device 1 is mounted on a vehicle, it is possible to avoid a decrease in the reliability of the power storage device 1.

As shown in FIG. 10A, the end portion 55 may further include a return piece 55e and a locking piece 55f. The return piece 55e is a portion extending from the other end of the inclined piece 55b along the direction D2. That is, one end of the return piece 55e is connected to the other end of the inclined piece 55b. With the end 55 fitted in the groove 5b, the return piece 55e extends along the inner surface of the wall 5c. The locking piece 55f is a portion bent upward from the other end of the return piece 55e. With the end 55 fitted in the groove 5b, the locking piece 55f may come into surface contact with the wall 5c in direction D2. Specifically, the locking piece 55f comes into surface contact with the end surface 5g of the conductive plate 5. The end surface 5g is a surface facing the surface 51a of the monitoring board 51.

In the configuration shown in FIG. 10A, the contact area between the end portion 55 and the conductive plate 5 can be further increased. This makes it possible to further reduce the contact resistance between the end portion 55 and the conductive plate 5.

After the connecting member 52 is connected to the conductive plate 5, the connecting member 52 may be connected to the monitoring board 51. At this time, the end portion 56 of the connecting member 52 is inserted into the through hole 51c provided in the monitoring board 51. However, in a state where the end portion 55 is fitted into the groove 5b, the connecting member 52 can rotate about the end portion 55 as an axis. Therefore, the end portion 56 may be displaced with respect to the through hole 51c of the monitoring board 51. On the other hand, in the configuration shown in FIG. 10A, the locking piece 55f comes into surface contact with the end surface 5g of the wall portion 5c in the direction D2 in a state where the end portion 55 is fitted into the groove 5b. .. Thereby, the position of the end portion 55 in the groove 5b is defined, and the misalignment of the end portion 55 can be regulated. Further, since the rotation of the connecting member 52 around the end portion 55 is suppressed, the extending direction of the connecting member 52 is defined. Therefore, the work of inserting the end portion 56 into the through hole 51c of the monitoring board 51 can be simplified.

As shown in FIG. 10 (b), the end 55 has a curved portion 55 g in place of the extending portion 55a, the inclined piece 55b, and the return piece 55e shown in FIG. 10 (a). You may. The curved portion 55g is a portion that is curved in a C shape. The curved portion 55g is curved so as to be convex toward the partition wall 5e that defines the groove 5b. One end of the curved portion 55g is connected to one end of the connecting portion 57, and the other end of the curved portion 55g is connected to one end of the locking piece 55f. Both ends of the curved portion 55g are in contact with the inner surface of the wall portion 5c and the inner surface of the wall portion 5d, respectively. In this configuration, since there are fewer bending points as compared with the configuration shown in FIG. 10A, it is possible to reduce the processing cost.

As shown in FIG. 11A, the end portion 55 has a spring portion 55h in place of the extending portion 55a, the inclined piece 55b, and the return piece 55e shown in FIG. 10A. You may. The spring portion 55h has, for example, a coil spring structure. The coil central axis of the spring portion 55h is along the opposite direction (stacking direction D1) between the wall portion 5c and the wall portion 5d. One end of the spring portion 55h is connected to one end of the connecting portion 57, and the other end of the spring portion 55h is connected to one end of the locking piece 55f. Both ends of the spring portion 55h are in contact with the inner surface of the wall portion 5c and the inner surface of the wall portion 5d, respectively. In order to increase the contact area between the end portion 55 and the conductive plate 5, both ends of the spring portion 55h may be closed loops or may be flattened by polishing or the like. In this configuration, the connecting member 52 can be configured with a single wire, so that the cost can be reduced.

The coil central axis of the spring portion 55h may be along the direction D3. Also in this case, the spring portion 55h can be elastically deformed in the stacking direction D1. Further, the conductive plate 5 may further have a pair of wall portions that sandwich the spring portion 55h in the direction D3.

As shown in FIG. 11B, the end portion 55 may have an extending portion 55a, a fitting portion 55i, and locking pieces 55f and 55j. The fitting portion 55i is a portion that fits into the groove 5b, and has substantially the same shape as the groove 5b. The fitting portion 55i is connected to the other end of the extending portion 55a at a portion facing the partition wall 5e. The locking piece 55f is a portion bent upward from one end of the fitting portion 55i. With the end 55 fitted in the groove 5b, the locking piece 55f may come into surface contact with the wall 5c in direction D2. The locking piece 55j is a portion bent downward from the other end of the fitting portion 55i. With the end 55 fitted in the groove 5b, the locking piece 55j may come into surface contact with the wall 5d in direction D2. In this configuration, the contact area between the end portion 55 and the conductive plate 5 can be further increased as compared with the configuration shown in FIG. 10A. This makes it possible to further reduce the contact resistance between the end portion 55 and the conductive plate 5. Further, since the locking pieces 55f and 55j come into surface contact with the wall portions 5c and 5d, respectively, the misalignment of the end portion 55 can be further regulated, and the extending direction of the connecting member 52 can be more reliably defined. it can.

As shown in FIG. 12, the connecting member 52 may be composed of a mounting member 65, a bolt 66, and a nut 67. The mounting member 65 is a member for mounting the bolt 66, and is fitted in the groove 5b. The mounting member 65 has a female screw portion 65a. The female screw portion 65a is a screw hole provided on the surface of the mounting member 65 facing the monitoring board 51. The bolt 66 has a head portion 66a and a shaft portion 66b. The shaft portion 66b has a male screw portion 66c at the tip end portion of the shaft portion 66b. The nut 67 is inserted through the shaft portion 66b of the bolt 66.

In this configuration, the shaft portion 66b of the bolt 66 is inserted into the through hole 51c of the monitoring board 51 from the surface 51b and is inserted into the nut 67. Then, the male screw portion 66c is screwed into the female screw portion 65a of the mounting member 65. As a result, the connecting member 52 is fixed to the conductive plate 5. The connecting member 52 is fixed to the monitoring board 51 by the head 66a of the bolt 66 and the nut 67. In this configuration, the mounting member 65 corresponds to the end 55, the head 66a of the bolt 66 corresponds to the end 56, and the shaft 66b of the bolt 66 corresponds to the connecting portion 57. Further, the nut 67 can reduce the possibility that the electrolytic solution reaches the monitoring substrate 51, similarly to the bent portion 58.

The shapes of the ends 56 and 62 are not limited to the shapes of the ends 56 and 62 of the above embodiment. The connection mode between the ends 56 and 62 and the monitoring board 51 is not limited to the connection mode of the above embodiment. For example, as shown in FIG. 13 (a), the end portion 56 may have a bent portion 56a. The bent portion 56a is a portion that is bent into a rectangular shape (U-shape). The bent portion 56a protrudes in a direction different from the direction D2 (in the direction (a) of FIG. 13 (a), the stacking direction D1). The bent portion 56a has a first portion 56b, a second portion 56c, and a third portion 56d. In a state where the end portion 56 is fixed to the monitoring substrate 51, the first portion 56b and the second portion 56c extend along the stacking direction D1 and face each other via the monitoring substrate 51. The first portion 56b is arranged on the surface 51a of the monitoring board 51, and the second portion 56c is arranged on the surface 51b of the monitoring board 51. The length of the first portion 56b is about the same as the length of the second portion 56c. The third portion 56d is a portion connecting the first portion 56b and the second portion 56c. In a state where the end portion 56 is fixed to the monitoring board 51, the third portion 56d is inserted into the through hole 51c provided in the monitoring board 51.

As shown in FIG. 13B, the through hole 51c has a rectangular shape extending in a direction different from the direction D2 (in FIG. 13B, the direction D3). The length of the through hole 51c in the direction D3 is larger than the length of the first portion 56b and the length of the second portion 56c. The length (thickness) of the monitoring board 51 in the direction D2 is substantially the same as the length of the third portion 56d. When the end portion 56 is attached to the monitoring board 51, after the second portion 56c is inserted into the through hole 51c with the extending directions of the first portion 56b and the second portion 56c aligned with the direction D3, The connecting member 52 is rotated by, for example, 90 degrees with the direction D2 as the axis in a state where the third portion 56d is located in the through hole 51c. As a result, the first portion 56b is arranged on the surface 51a and the second portion 56c is arranged on the surface 51b. Then, the gap of the through hole 51c is filled with solder or the like, and the bent portion 56a is fixed to the monitoring board 51. In this way, the first portion 56b and the second portion 56c sandwich the monitoring board 51 in the direction D2, so that the end portion 56 is fixed to the monitoring board 51.

In this configuration, the end portion 56 can be more firmly fixed to the monitoring board 51. In the state where the end portion 56 is fixed to the monitoring board 51, the first portion 56b and the second portion 56c are not limited to the stacking direction D1 but are defined by the stacking direction D1 and the direction D3 (virtual surface). It suffices if it extends along. In this case, the through hole 51c extends in the direction intersecting the extending direction of the first portion 56b and the second portion 56c on the virtual surface. To give an example, when the first portion 56b and the second portion 56c extend along the direction D3 in a state where the end portion 56 is fixed to the monitoring board 51, the through hole 51c is, for example, the stacking direction D1. Extends along. The configurations shown in FIGS. 13 (a) and 13 (b) may be applied to the end 62 of the connecting member 60. That is, the end portion 62 may have a bent portion similar to the bent portion 56a, and the through hole 51d for inserting the end portion 62 may have a rectangular shape like the through hole 51c. Good. Also in this case, the end portion 62 can be more firmly fixed to the monitoring board 51.

The shapes of the bent portions 58 and 64 are not limited to the shapes of the bent portions 58 and 64 of the above embodiment. As described above, the bent portions 58 and 64 may be bent in a direction different from the direction D2 in order to relieve the stress. In order to further reduce the possibility of a short circuit due to liquid leakage, the bent portions 58 and 64 may include a portion that bends upward so as to move away from the power storage module 4B in the stacking direction D1 toward the monitoring substrate 51.

For example, as shown in FIG. 14A, the connecting portion 63 is bent so that the portion of the connecting portion 63 closer to the end portion 61 is located above the portion closer to the end portion 62. It may have been. In this example, the bent portion 64 is a stepped portion that connects a portion close to the end portion 61 and a portion close to the end portion 62. In other words, the bent portion 64 is a portion that inclines upward toward the monitoring board 51. Also in this configuration, the stress applied to the connecting member 60 can be relaxed and the possibility of a short circuit due to liquid leakage can be reduced, as in the case of the bent portion 64 of the above embodiment. Further, in this configuration, since there are few bent portions, the connecting member 60 can be easily formed. The configuration shown in FIG. 14 (a) may be applied to the bent portion 58.

As shown in FIG. 14 (b), the bent portion 64 may have a helical structure. Also in this configuration, the stress applied to the connecting member 60 can be relaxed and the possibility of a short circuit due to liquid leakage can be reduced, as in the case of the bent portion 64 of the above embodiment. Further, in this configuration, it is possible to improve the impact resistance and vibration resistance of the connecting member 60. The configuration shown in FIG. 14 (b) may be applied to the bent portion 58.

The conductive plate 5 may include a pair of wall portions facing each other in a direction different from the stacking direction D1 and a wall portion connecting the pair of wall portions. The end portion 55 and the temperature sensor 59 may be fitted into the groove defined by these wall portions. In this case, the conductive plate 5 may not be provided with the groove 5b.

For example, as shown in FIG. 15, the end 55 may be fitted into the flow path 5a. In this case, among the side surfaces of the module laminate 2, the side surface on which the flow path 5a is provided is different from the side surface 2a, so that the end portion 55 may extend from the connecting portion 57 along the direction D3. Similarly, the temperature sensor 59 may be fitted into the flow path 5a. In this way, by using the heat dissipation flow path 5a, it is not necessary to provide a groove only for connecting the connecting member 52 and the temperature sensor unit 53. Therefore, it is possible to simplify the production of the conductive plate 5.

As shown in FIGS. 16, 17, and 18, the monitoring device 50 may further include a guide member 70 (holding member). The guide member 70 is a member for assisting the work of fitting the end portion 55 into the groove 5b. The guide member 70 is provided so as to be adjacent to the conductive plate 5 in the direction D2. The guide member 70 is located between the conductive plate 5 and the monitoring board 51. The guide member 70 is placed on a power storage module 4 (power storage module 4B) located on the lower side of the two power storage modules 4 electrically connected by the conductive plate 5.

The guide member 70 has an upper surface 70a, a lower surface 70b, an end surface 70c (first end surface), and an end surface 70d (second end surface). The upper surface 70a faces the lower surface (positive electrode terminal electrode 19) of the electricity storage module 4 (storage module 4A) located on the upper side of the two energy storage modules 4 electrically connected by the conductive plate 5. The upper surface 70a may be in contact with the lower surface of the power storage module 4A. The lower surface 70b faces the upper surface (negative electrode end electrode 18) of the power storage module 4B. The lower surface 70b is in contact with the upper surface of the power storage module 4B. The end face 70c faces the monitoring board 51 (face 51a). The end face 70d faces the conductive plate 5 (groove 5b). The end face 70d may be in contact with the conductive plate 5 (end face 5g).

The guide member 70 is provided with an insertion hole 71 and an accommodation space 72. The insertion hole 71 is a through hole that penetrates the guide member 70 along the direction D2. The insertion hole 71 has a shape through which the end portion 55 can be inserted. The insertion hole 71 is defined by a support surface 71a, an inclined surface 71b, a side surface 71c, and a side surface 71d. The support surface 71a is a surface that intersects the stacking direction D1 and extends along the direction D2, and is connected to the inner surface of the wall portion 5d. The inclined surface 71b faces the support surface 71a in the stacking direction D1, and is inclined so as to approach the support surface 71a as it approaches the end surface 70d in the direction D2. The distance Lin between the support surface 71a and the inclined surface 71b on the end surface 70c is larger than the separation distance Lg between the wall portion 5c and the wall portion 5d. The distance Lout between the support surface 71a and the inclined surface 71b on the end surface 70d is smaller than the separation distance Lg. The side surfaces 71c and 71d are surfaces that connect the support surface 71a and the inclined surface 71b on both sides of the direction D3.

The accommodation space 72 is a space for accommodating (holding) the temperature sensor 59. That is, the guide member 70 also functions as a holding member for holding the temperature sensor 59. In this example, since the temperature sensor 59 detects the temperature of the power storage module 4A, the accommodation space 72 holds the temperature sensor 59 so that the temperature of the power storage module 4A can be detected. For example, the accommodation space 72 holds the temperature sensor 59 so that the temperature sensor 59 comes into contact with the positive electrode terminal 19 of the power storage module 4A.

The accommodation space 72 is defined by a support surface 72a and side surfaces 72b to 72d. The support surface 72a is a surface facing the power storage module 4A (positive electrode terminal electrode 19). The support surface 72a supports the temperature sensor 59 accommodated in the accommodation space 72. The support surface 72a extends from the end surface 70c along the direction D2. The side surfaces 72b and 72c are surfaces that extend from both sides of the support surface 72a in the direction D3 to the upper surface 70a along the stacking direction D1 and face each other in the direction D3. Each of the side surfaces 72b and 72c extends from the end surface 70c along the direction D2. The separation distance between the side surface 72b and the side surface 72c in the direction D3 is the same as or slightly larger than the length in the direction D3 of the temperature sensor 59. The side surface 72d is a surface extending from one side of the support surface 72a in the direction D2 to the upper surface 70a along the stacking direction D1, and connects the side surfaces 72b and 72c.

The temperature sensor 59 is inserted into the accommodation space 72 from the end surface 70c and placed on the support surface 72a. Since the temperature sensor 59 mounted on the support surface 72a is exposed from the upper surface 70a of the guide member 70, it can come into contact with the positive electrode terminal electrode 19 of the power storage module 4A.

In this configuration, the end portion 55 is inserted into the groove 5b of the conductive plate 5 through the insertion hole 71 of the guide member 70. At this time, since the distance Lin is larger than the separation distance Lg, the operator can insert the end portion 55 into the insertion hole 71 of the guide member 70 without compressing the end portion 55 in the stacking direction D1. Further, since the inclined surface 71b is inclined so as to approach the support surface 71a as it approaches the end surface 70d in the direction D2, the end portion 55 advances as the end portion 55 advances the insertion hole 71 from the end surface 70c toward the end surface 70d. It is gradually compressed in the stacking direction D1. Then, since the distance Lout is smaller than the separation distance Lg, the end portion 55 is inserted into the groove 5b in a state of being compressed in the stacking direction D1. In this way, the end portion 55 can be fitted into the groove 5b simply by inserting the end portion 55 into the groove 5b of the conductive plate 5 through the insertion hole 71 of the guide member 70. Therefore, it is possible to improve the workability of connecting the end portion 55 to the conductive plate 5.

Further, since the distance Lout is smaller than the separation distance Lg, when the end portion 55 tries to come out of the groove 5b due to vibration or the like, the end portion 55 may interfere with the guide member 70 in the direction D2. Therefore, once the end portion 55 is fitted into the groove 5b, the end portion 55 is prevented from coming out of the groove 5b. As a result, even when the power storage device 1 is mounted on the vehicle, it is possible to avoid a decrease in the reliability of the power storage device 1.

The guide member 70 is provided with an accommodation space 72 for accommodating the temperature sensor 59. Therefore, the temperature sensor 59 can be positioned only by accommodating the temperature sensor 59 in the accommodation space 72. Further, since it is not necessary to provide the conductive plate 5 with a groove for fitting the temperature sensor 59, the structure of the conductive plate 5 can be simplified. Further, since one guide member 70 accommodates the temperature sensor 59 and assists in inserting the end portion 55, it is possible to suppress an increase in the number of parts.

The guide member 70 may not be provided with either the insertion hole 71 or the accommodation space 72. For example, when the monitoring device 50 includes a signal line composed of a wire harness instead of the connecting member 52, the guide member 70 may not be provided with the insertion hole 71. Similarly, when the monitoring device 50 includes a signal line composed of a wire harness instead of the connecting member 60, the guide member 70 may not be provided with the accommodation space 72. Further, even when the monitoring device 50 includes the connecting member 52 and the temperature sensor unit 53, the guide member 70 may not be provided with either the insertion hole 71 or the accommodation space 72. For example, in the configuration in which the temperature sensor 59 is fitted into the groove 5b, the guide member 70 may not be provided with the accommodation space 72. When the guide member 70 is not provided with the insertion hole 71, the end portion 55 is fitted into the groove 5b without passing through the insertion hole 71.

As shown in FIG. 19, the guide member 70 may further have an inclined surface 72e between the support surface 72a and the end surface 70c. Specifically, the inclined surface 72e extends from the end surface 70c to the support surface 72a in the direction D2 and is connected to the support surface 72a. The inclined surface 72e is inclined downward so that the distance from the power storage module 4A to be detected increases toward the end surface 70c from the support surface 72a (as the distance from the support surface 72a increases). In this configuration, the inclined surface 72e can function as a guide when the temperature sensor 59 is accommodated in the accommodation space 72. Therefore, it is possible to improve the workability of accommodating the temperature sensor 59 in the accommodating space 72.

As shown in FIG. 20, the temperature sensor unit 53 may further include an elastic member 68 provided between the temperature sensor 59 and the support surface 72a. The elastic member 68 is provided on the lower surface facing the support surface 72a of the temperature sensor 59. The elastic member 68 can be elastically deformed in the stacking direction D1. As the elastic member 68, for example, a leaf spring is used. The temperature sensor 59 is accommodated in the accommodation space 72 in a state where the elastic member 68 is compressed in the stacking direction D1. In this configuration, the elastic member 68 presses the temperature sensor 59 toward the power storage module 4A to be detected. This makes it possible to improve the temperature detection accuracy of the power storage module 4A.

In the above embodiment, the temperature sensor unit 53 may further include an elastic member 68. In this case, the elastic member 68 is provided between the temperature sensor 59 and the wall portion 5d. The temperature sensor 59 is housed in the groove 5b in a state where the elastic member 68 is compressed in the stacking direction D1. In this configuration, the elastic member 68 presses the temperature sensor 59 against the wall portion 5c. Therefore, the temperature sensor 59 is firmly fixed to the wall portion 5c. This makes it possible to improve the temperature detection accuracy of the power storage module 4A.

In a power storage device as described in Patent Document 1, the state of each power storage module may be monitored by detecting the voltage of each power storage module. In each power storage module, the internal space containing the electrolytic solution is sealed by a sealant, but the electrolytic solution may leak from the power storage module through between the sealant and the bipolar electrode. .. If the electrolytic solution leaks from the power storage module and diffuses, a short circuit may occur between the wirings for voltage detection via the electrolytic solution. Therefore, in the present technical field, a power storage device with improved reliability is desired.

FIG. 21 is a schematic cross-sectional view showing a modified example of the power storage device. The power storage device 1A shown in FIG. 21 is mainly different from the power storage device 1 in that the monitoring device 50A is provided in place of the monitoring device 50. The monitoring device 50A is mainly different from the monitoring device 50 in the arrangement of the connecting member 52.

FIG. 22 is a diagram showing an example of arrangement of connecting members in the power storage device shown in FIG. Here, in order to distinguish each connecting member 52, the connecting members 52A to 52F are used. The connecting members 52A to 52F are arranged in that order in the stacking direction D1. Of the connecting members 52A to 52F, the connecting member 52A is located at the top and the connecting member 52F is located at the bottom. As shown in FIG. 22, of the plurality of connecting members 52, the two connecting members 52 adjacent to each other in the stacking direction D1 are separated from each other in the direction D3. That is, the connecting member 52A and the connecting member 52B are separated from each other in the direction D3. The connecting member 52B (first connecting member) and the connecting member 52C (second connecting member) are separated from each other in the direction D3. The connecting member 52C and the connecting member 52D are separated from each other in the direction D3. The connecting member 52D and the connecting member 52E are separated from each other in the direction D3. The connecting member 52E and the connecting member 52F are separated from each other in the direction D3.

In the arrangement example shown in FIG. 22, the connecting members 52A to 52F are provided at different positions in the direction D3. That is, when the power storage device 1A is viewed from the stacking direction D1, each connecting member 52 does not overlap with the other connecting members 52. The connecting members 52A to 52F are arranged in that order in the direction D3, but the order in the direction D3 may be changed as long as they are provided at different positions in the direction D3.

The power storage device 1A also has the same effect as that of the power storage device 1. In the power storage device 1A, two connecting members 52 (for example, connecting members 52A and 52B) adjacent to each other in the stacking direction D1 are separated from each other in the direction D3. When the power storage device 1A is arranged and used so that the stacking direction D1 is in the vertical direction (for example, the vertical direction) and the negative electrode terminal 7 is located above the positive electrode terminal 6, the connecting member 52A is connected. Although it is located above the member 52B, the connecting member 52B is not located directly below the connecting member 52A. Therefore, even if the electrolytic solution leaked from the power storage module 4 reaches the monitoring board 51 along the connecting member 52A and drops due to gravity on the monitoring board 51, there is a possibility that the electrolytic solution will reach the connecting member 52B. Low. In this way, in the monitoring board 51, the possibility that the connecting member 52A and the connecting member 52B are short-circuited via the electrolytic solution can be reduced. Similarly, the combination of the connecting members 52B, 52C, the connecting members 52C, 52D, the connecting members 52D, 52E, and the connecting members 52E, 52F can also reduce the possibility of short-circuiting via the electrolytic solution.

Further, in the power storage device 1A, the connection members 52A to 52F are provided at different positions in the direction D3, and when the power storage device 1A is viewed from the stacking direction D1, each connection member 52 is the other connection member 52. Does not overlap with. Therefore, even if the electrolytic solution reaches the monitoring board 51 along any one of the connecting members 52 and is dropped by gravity on the monitoring board 51, it is unlikely that the electrolytic solution will reach the other connecting members 52. Therefore, it is possible to reduce the possibility that a short circuit is generated between the two connecting members 52 among the connecting members 52A to 52F via the electrolytic solution. As a result, the reliability of the power storage device 1A can be improved.

Also in the power storage device 1A, each of the connecting members 52A to 52F has a bent portion 58. The bent portion 58 is located between the module laminate 2 and the monitoring board 51 in the direction D2. When the power storage device 1A is arranged and used so that the stacking direction D1 is in the vertical direction (for example, the vertical direction) and the negative electrode terminal 7 is located above the positive electrode terminal 6, the bent portion 58 is downward. It becomes convex. That is, the bent portion 58 has a portion that inclines upward from the conductive plate 5 toward the monitoring board 51. Therefore, when the electrolytic solution is transmitted toward the monitoring substrate 51 along the bent portion 58, the electrolytic solution is affected by gravity. Therefore, the electrolytic solution is suppressed from being transmitted beyond the bent portion 58, and may fall from each connecting member 52. As a result, the possibility that the electrolytic solution reaches the monitoring board 51 can be reduced, and the occurrence of a short circuit can be further suppressed. It should be noted that each of the connecting members 52A to 52F does not have to have the bent portion 58.

FIG. 23 is a diagram showing another arrangement example of the connecting member in the power storage device shown in FIG. The arrangement example shown in FIG. 23 is mainly different from the arrangement example shown in FIG. 22 in the arrangement of the connecting members 52D to 52F. As shown in FIG. 23, as in the arrangement example shown in FIG. 22, two connecting members 52 adjacent to each other in the stacking direction D1 among the plurality of connecting members 52 are separated from each other in the direction D3. However, the connecting member 52A and the connecting member 52D overlap each other when viewed from the stacking direction D1. The connecting member 52B and the connecting member 52E (third connecting member) overlap each other when viewed from the stacking direction D1. The connecting member 52C and the connecting member 52F overlap each other when viewed from the stacking direction D1. In this arrangement example, the connecting member 52D is located directly below the connecting member 52A, the connecting member 52E is located directly below the connecting member 52B, and the connecting member 52F is located directly below the connecting member 52C.

The separation distance L1 between the connecting member 52A and the connecting member 52D, the separation distance L2 between the connecting member 52B and the connecting member 52E, and the separation distance L3 between the connecting member 52C and the connecting member 52F are substantially the same as each other. The distance is such that the two connecting members 52 are not short-circuited by the electrolytic solution. The distance at which the electrolytic solution does not cause a short circuit is determined in advance by experiments or the like.

In this configuration, the connecting members 52B and 52C are arranged between the connecting member 52A and the connecting member 52D in the stacking direction D1. Therefore, the separation distance L1 is larger than the distance in the stacking direction D1 between the connecting member 52A and the connecting member 52B and the distance in the stacking direction D1 between the connecting member 52A and the connecting member 52C. Therefore, even if the electrolytic solution that has reached the monitoring board 51 along the connecting member 52A drops due to gravity, the connecting member 52A and the connecting member 52D are separated from each other, so that the connecting member 52A and the connecting member 52D supply the electrolytic solution. It is possible to reduce the possibility of short-circuiting through. Similarly, since the connecting member 52B and the connecting member 52E are separated from each other, the possibility that the connecting member 52B and the connecting member 52E are short-circuited via the electrolytic solution can be reduced. Since the connecting member 52C and the connecting member 52F are separated from each other, the possibility that the connecting member 52C and the connecting member 52F are short-circuited via the electrolytic solution can be reduced.

1,1A ... power storage device, 4 ... power storage module (first power storage module, second power storage module, third power storage module, fourth power storage module), 4A ... power storage module (first power storage module), 4B ... power storage module (first power storage module) 2 power storage module), 5 ... Conductive plate (1st conductive plate, 2nd conductive plate), 5a ... Flow path (through hole), 5b ... Groove, 5c ... Wall part (1st wall part), 5d ... Wall part ( 2nd wall part), 5e ... partition wall (3rd wall part), 5f ... projecting part, 11 ... electrode laminate, 12 ... sealant, 14 ... bipolar electrode, 50 ... monitoring device, 51 ... monitoring substrate (fixed part) ), 52 ... Connecting member, 52A ... Connecting member (first connecting member), 52B ... Connecting member (second connecting member), 52D ... Connecting member (third connecting member), 53 ... Temperature sensor unit, 55 ... End (1st end), 55a ... Extension, 55b ... Inclined piece (1st inclined piece), 55c ... Inclined piece (2nd inclined piece), 55f ... Locking piece, 55j ... Locking piece, 56 ... End Part (second end), 56b ... first part, 56c ... second part, 57 ... connecting part, 58 ... bent part, 59 ... temperature sensor, 60 ... connecting member, 61 ... end (first end) , 62 ... end (second end), 63 ... connecting, 64 ... bent, 68 ... elastic member, 70 ... guide member (holding member), 70c ... end face (first end face), 70d ... end face (first) 2 end surface), 71 ... insertion hole, 71a ... support surface, 71b ... inclined surface, 72 ... accommodating space, 72a ... supporting surface, 72e ... inclined surface, D1 ... stacking direction (first direction), D2 ... direction (second direction) Direction), D3 ... direction (third direction), V ... internal space.

Claims (36)

The first power storage module and the second power storage module stacked along the first direction,
A conductive plate sandwiched between the first power storage module and the second power storage module and electrically connecting the first power storage module and the second power storage module.
In the second direction intersecting the first direction, the first power storage module and the second power storage module are provided adjacent to each other to monitor the voltage of the first power storage module and the voltage of the second power storage module. With the board
A connecting member for voltage monitoring that electrically connects the conductive plate and the monitoring board and extends along the second direction.
With
Each of the first power storage module and the second power storage module includes an electrode laminate including a plurality of bipolar electrodes laminated along the first direction.
The connecting member includes a first end portion connected to the conductive plate, a second end portion connected to the monitoring board, and a connecting portion connecting the first end portion and the second end portion. A power storage device. The power storage device according to claim 1, wherein the connecting portion has a bent portion that bends in a direction different from the second direction. Each of the first power storage module and the second power storage module
A seal provided around the electrode laminate to form an internal space between two bipolar electrodes adjacent to each other in the first direction of the plurality of bipolar electrodes and to seal the internal space. With the body
The electrolytic solution housed in the internal space and
With more
The bent portion has a portion that bends away from the second power storage module toward the monitoring board.
The power storage device according to claim 2, wherein the bent portion is located between the first power storage module and the second power storage module and the monitoring board in the second direction. The power storage device according to claim 3, wherein the bent portion has a convex shape protruding away from the first power storage module in the first direction. The first portion of the second end extends along a plane defined by the first direction, the first direction, and the third direction intersecting the second direction, and faces each other in the second direction. And has a second part,
The invention according to any one of claims 1 to 4, wherein the first portion and the second portion sandwich the monitoring board, whereby the second end portion is fixed to the monitoring board. Power storage device. The conductive plate has a first wall portion and a second wall portion facing each other, and a third wall portion connecting the first wall portion and the second wall portion.
The first wall portion is described in any one of claims 1 to 5, wherein the first end portion fits into a groove defined by the first wall portion, the second wall portion, and the third wall portion. Power storage device. The first end portion has a shape that can be elastically deformed in the direction in which the first wall portion and the second wall portion face each other.
The power storage device according to claim 6, wherein the first end portion is held by the elastic force of the first end portion on the first wall portion and the second wall portion. The first end portion forms an acute angle with the extending portion extending from the connecting portion along the second direction and the extending portion so as to approach the first wall portion toward the connecting portion. The power storage device according to claim 7, further comprising a first inclined piece that is inclined. The first end portion extends from the first inclined piece toward the second wall portion, and further increases the second inclined piece that inclines toward the second wall portion as the distance from the first inclined piece increases. The power storage device according to claim 8. The power storage device according to claim 9, wherein a part of the second inclined piece is located outside the groove. A guide member provided so as to be adjacent to the conductive plate in the second direction is further provided.
The guide member has a first end surface facing the monitoring substrate and a second end surface facing the conductive plate.
The guide member is provided with an insertion hole that penetrates the guide member along the second direction and allows the first end portion to be inserted.
The insertion hole is defined by a support surface extending along the second direction and an inclined surface that inclines so as to approach the support surface as it approaches the second end surface in the second direction.
The distance between the support surface and the inclined surface on the first end surface is larger than the separation distance between the first wall portion and the second wall portion.
The method according to any one of claims 7 to 10, wherein the distance between the support surface and the inclined surface on the second end surface is smaller than the separation distance between the first wall portion and the second wall portion. Power storage device. The power storage device according to claim 11, wherein the guide member is provided with a storage space for housing a temperature sensor that detects the temperature of the first power storage module. The invention according to any one of claims 6 to 10, wherein the conductive plate further has a protruding portion provided on the first wall portion and projecting from the first wall portion toward the second wall portion. Power storage device. The power storage device according to any one of claims 6 to 10, wherein the connecting member further has a locking piece that comes into surface contact with the first wall portion in the second direction. Claims 6 to 6, wherein the length of the first end portion is longer than the length of the connecting portion in the direction in which the first wall portion and the second wall portion face each other and in the direction in which the second wall portion intersects the second direction. Item 2. The power storage device according to any one of items 14. The power storage device according to any one of claims 6 to 15, wherein the first wall portion and the second wall portion face each other in the first direction. The power storage device according to any one of claims 1 to 5, wherein the conductive plate is provided with a through hole for allowing a refrigerant to flow. The power storage device according to any one of claims 6 to 16, wherein the conductive plate is provided with a through hole for allowing a refrigerant to flow. The power storage device according to claim 18, wherein the groove is the through hole. The first power storage module and the second power storage module stacked along the first direction,
A conductive plate sandwiched between the first power storage module and the second power storage module and electrically connecting the first power storage module and the second power storage module.
A monitoring board provided adjacent to the first power storage module and the second power storage module in the second direction intersecting the first direction and monitoring the temperature of the first power storage module.
A temperature sensor unit for detecting the temperature of the first power storage module and
With
Each of the first power storage module and the second power storage module includes an electrode laminate including a plurality of bipolar electrodes laminated along the first direction.
The temperature sensor unit is provided so as to be adjacent to the first power storage module in the first direction, and electrically connects the temperature sensor for detecting the temperature of the first power storage module, the temperature sensor, and the monitoring board. A connecting member that connects and extends along the second direction is provided.
The connecting member includes a first end portion connected to the temperature sensor, a second end portion connected to the monitoring board, and a connecting portion connecting the first end portion and the second end portion. A power storage device. The power storage device according to claim 20, wherein the connecting portion has a bent portion that bends in a direction different from the second direction. Each of the first power storage module and the second power storage module
A seal provided around the electrode laminate to form an internal space between two bipolar electrodes adjacent to each other in the first direction of the plurality of bipolar electrodes and to seal the internal space. With the body
The electrolytic solution housed in the internal space and
With more
The bent portion has a portion that bends away from the second power storage module toward the monitoring board.
The power storage device according to claim 21, wherein the bent portion is located between the first power storage module and the second power storage module and the monitoring board in the second direction. The power storage device according to claim 22, wherein the bent portion has a convex shape protruding away from the first power storage module in the first direction. The first portion of the second end extends along a plane defined by the first direction, the first direction, and the third direction intersecting the second direction, and faces each other in the second direction. And has a second part,
The invention according to any one of claims 20 to 23, wherein the first portion and the second portion sandwich the monitoring board so that the second end portion is fixed to the monitoring board. Power storage device. The conductive plate has a first wall portion and a second wall portion facing each other, and a third wall portion connecting the first wall portion and the second wall portion.
The power storage device according to any one of claims 20 to 24, wherein the temperature sensor fits into a groove defined by the first wall portion, the second wall portion, and the third wall portion. .. The power storage device according to claim 25, wherein the first wall portion and the second wall portion face each other in the first direction. The first wall portion is in contact with the first power storage module.
The power storage device according to claim 25 or 26, wherein the temperature sensor unit further includes an elastic member provided between the temperature sensor and the second wall portion. The power storage device according to any one of claims 20 to 24, further comprising a holding member which is provided adjacent to the conductive plate in the second direction and holds the temperature sensor. The holding member has a support surface that faces the first power storage module and supports the temperature sensor.
28. The power storage device according to claim 28, wherein the support surface defines an accommodation space for accommodating the temperature sensor. The holding member further has an inclined surface that is connected to the support surface in the second direction.
29. The power storage device according to claim 29, wherein the inclined surface is inclined so that the distance from the first power storage module increases as the distance from the support surface increases. The power storage device according to claim 29 or 30, wherein the temperature sensor unit further includes an elastic member provided between the temperature sensor and the support surface. The power storage device according to any one of claims 20 to 31, wherein the conductive plate is provided with a through hole for allowing a refrigerant to flow. Multiple power storage modules stacked along the first direction,
Among the plurality of power storage modules, a first power storage module and a second power storage module that are adjacent to each other in the first direction sandwich the plurality of power storage modules, and the first power storage module and the second power storage module are electrically connected. 1 Conductive plate and
In the first direction, a second conductive plate provided so as to be adjacent to the first conductive plate via the second power storage module and electrically connected to the second power storage module.
A first connecting member for voltage monitoring, which is connected to the first conductive plate and extends along a second direction intersecting the first direction.
A second connecting member for voltage monitoring, which is connected to the second conductive plate and extends along the second direction.
In the second direction, a fixing portion provided adjacent to the plurality of power storage modules and fixing the first connecting member and the second connecting member, and
With
Each of the plurality of power storage modules
An electrode laminate including a plurality of bipolar electrodes laminated along the first direction, and
A seal provided around the electrode laminate to form an internal space between two bipolar electrodes adjacent to each other in the first direction of the plurality of bipolar electrodes and to seal the internal space. With the body
The electrolytic solution housed in the internal space and
With
A power storage device in which the first connecting member and the second connecting member are separated from each other in a third direction intersecting the first direction and the second direction. Of the plurality of power storage modules, the third power storage module and the fourth power storage module that are adjacent to each other in the first direction are provided, and the third power storage module and the fourth power storage module are electrically connected. 3rd conductive plate and
A third connecting member for voltage monitoring, which is connected to the third conductive plate and extends along the second direction.
With more
The fixing portion further fixes the third connecting member.
The first connecting member, the second connecting member, and the third connecting member are arranged in that order in the first direction.
The power storage device according to claim 33, wherein the first connecting member and the third connecting member overlap each other when viewed from the first direction. The first connecting member has a bent portion that bends away from the second connecting member as it approaches the fixed portion.
The power storage device according to claim 33 or 34, wherein the bent portion is located between the plurality of power storage modules and the fixed portion in the second direction. A monitoring board for monitoring the voltages of the plurality of power storage modules is further provided.
The power storage device according to any one of claims 33 to 35, wherein the fixing portion is the monitoring board.

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