JP6824777B2 - Power storage device - Google Patents

Description

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

A bipolar battery having a laminate in which a bipolar electrode including an electrode plate, a positive electrode provided on one surface of the electrode plate, and a negative electrode provided on the other surface of the electrode plate is laminated is known (for example, Patent Document). 1). In this bipolar battery, the power storage module is configured by surrounding the laminate with a resin-made sealing material (frame). Further, the bipolar battery is configured by connecting the power storage module to the current collector on the negative electrode side and the current collector on the positive electrode side.

Japanese Unexamined Patent Publication No. 2012-234823

Here, in the power storage device as described above, a plurality of power storage modules may be connected in parallel. Further, among the power generation units provided in parallel, a plurality of layers of power storage modules may be stacked. On the other hand, when a power storage device is configured by using a plurality of power storage modules, it is necessary to monitor the voltage at each location in the power storage device. Therefore, it is necessary to increase the number of voltage monitoring units as the number of power storage modules increases. However, there is a problem that the cost of the power storage device increases as the number of voltage monitoring units increases. Therefore, when the power storage modules are provided in parallel, it has been required to suppress an increase in the number of voltage monitoring units provided in the power storage device.

One aspect of the present invention is to provide a power storage device capable of suppressing an increase in the number of voltage monitoring units when the power storage modules are provided in parallel.

The power storage device according to one aspect of the present invention includes a negative electrode current collector electrically connected to a negative electrode terminal, a positive electrode current collector electrically connected to a positive electrode terminal, a negative electrode current collector, and a positive electrode current collector. A power storage device including at least a first power generation unit and a second power generation unit connected in parallel with each other and a voltage monitoring unit for monitoring the voltage, and the first power generation unit and the second power generation unit are relay collections. A bipolar electrode including a plurality of power storage modules laminated via an electric unit, the power storage module includes an electrode plate, a positive electrode provided on one surface of the electrode plate, and a negative electrode provided on the other surface of the electrode plate. A laminated body in which a plurality of electrodes are laminated and a frame body that holds the edge of the electrode plate on the side surface of the laminated body extending in the stacking direction of the bipolar electrodes, and the relay current collecting unit is a storage unit of the first power generation unit. It includes a first conductive plate laminated on the module, a second conductive plate laminated on the power storage module of the second power generation unit, and a connecting portion for electrically connecting the first conductive plate and the second conductive plate. ..

In this power storage device, at least the first power generation unit and the second power generation unit are connected in parallel to the negative electrode current collector and the positive electrode current collector. The first power generation unit and the second power generation unit include a plurality of power storage modules stacked via a relay current collector. In the power storage device having such a configuration, the relay current collecting unit includes a first conductive plate laminated on the power storage module of the first power generation unit, a second conductive plate laminated on the power storage module of the second power generation unit, and the like. It is provided with a connecting portion for electrically connecting the first conductive plate and the second conductive plate. In this way, the first power generation unit and the second power generation unit connected in parallel are electrically connected via the relay current collector, so that the voltages in the relay current collector are equal to each other. As described above, when the power storage modules are provided in parallel, it is possible to suppress an increase in the number of voltage monitoring units provided in the power storage device.

The first conductive plate and the second conductive plate of the relay current collector may be provided with voids through which the refrigerant passes. As a result, the first conductive plate and the second conductive plate also have a function as a cooling plate for cooling the power storage module.

The connection portion of the relay current collector may have a solid configuration. The connection portion is provided at a position different from that of the power storage module. Even if the connection portion is provided with a gap through which the refrigerant passes, the cooling efficiency is low. Therefore, by providing a solid structure without providing a gap in the connection portion, it is possible to suppress the flow of the refrigerant to a portion having low cooling efficiency.

The frame body may include a plurality of first resin portions that hold the edges of the electrode plates, and a second resin portion that is provided around the first resin portion when viewed from the stacking direction. Thereby, the sealing property of the power storage module can be improved.

The voltage monitoring unit may be connected to the relay current collecting unit. The voltage monitoring unit connected to the relay current collecting unit can simultaneously monitor the voltages of the first power generation unit and the second power generation unit at the position. That is, since it is not necessary to provide a voltage monitoring unit for each of the first power generation unit and the second power generation unit, the number of required voltage monitoring units can be reduced.

According to one aspect of the present invention, it is possible to provide a power storage device capable of suppressing an increase in the number of voltage monitoring units when the power storage modules are provided in parallel.

It is schematic cross-sectional view which shows one Embodiment of the power storage device including the power storage module. It is schematic cross-sectional view which shows the power storage module which comprises the power storage device of FIG. It is the schematic sectional drawing of the power storage device which concerns on a comparative example. It is a circuit diagram of the power storage device which concerns on this Embodiment and a comparative example.

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. The drawing shows the XYZ Cartesian coordinate system.

FIG. 1 is a schematic cross-sectional view showing an embodiment of a power storage device including a power storage module. The power storage device 10 shown in the figure is used as a battery for various vehicles such as forklifts, hybrid vehicles, and electric vehicles. The power storage module 12 is, for example, a bipolar battery. The power storage module 12 is a secondary battery such as a nickel hydrogen secondary battery or a lithium ion secondary battery, but may be an electric double layer capacitor. In the following description, a nickel hydrogen secondary battery will be illustrated.

The power storage device 10 includes a negative electrode current collector 61 electrically connected to the negative electrode terminal 26, a positive electrode current collector 62 electrically connected to the positive electrode terminal 24, a negative electrode current collector 61, and a positive electrode current collector 62. A first power generation unit 63A and a second power generation unit 63B, which are connected in parallel with each other, are provided. The first power generation unit 63A and the second power generation unit 63B include a plurality of power storage modules 12 stacked via relay current collection units 64 and 65. The first power generation unit 63A is configured by alternately stacking a plurality of power storage modules 12 and conductive plates 14 such as metal plates. Further, the portion of each of the current collectors 61 and 62 corresponding to the first power generation unit 63A is configured by laminating conductive plates 14 on the outside of the power storage modules 12 at both ends in the stacking direction of the first power generation unit 63A. Ru. The second power generation unit 63B is configured by alternately stacking a plurality of power storage modules 12 and conductive plates 14 such as metal plates. Further, the portion of each of the current collectors 61 and 62 corresponding to the second power generation unit 63B is configured by laminating conductive plates 14 on the outside of the power storage modules 12 at both ends in the stacking direction of the second power generation unit 63B. Ru. The details of the arrangement of each component of the power storage device 10 will be described later.

Seen from the stacking direction, the power storage module 12 and the conductive plate 14 have, for example, a rectangular shape. The conductive plate 14 can also function as a heat radiating plate for releasing the heat generated in the power storage module 12. A plurality of voids 14a through which the refrigerant passes are formed in the conductive plate 14. By allowing a refrigerant such as air to pass through the plurality of voids 14a provided inside the conductive plate 14, the heat from the power storage module 12 can be efficiently released to the outside. Each void 14a extends in a direction (Y direction) intersecting the stacking direction, for example. The conductive plate 14 is smaller than the power storage module 12 when viewed from the stacking direction, but may be the same as or larger than the power storage module 12.

The power storage device 10 may include a restraint member 16 that restrains the alternately stacked power storage modules 12 and the conductive plates 14 in the stacking direction. The restraint member 16 includes a pair of restraint plates 16A and 16B and connecting members (bolts 18 and nuts 20) that connect the restraint plates 16A and 16B to each other. The restraint plates 16A and 16B can be restrained at the same time with the first power generation unit 63A and the second power generation unit 63B arranged in parallel. An insulating film 22 such as a resin film is arranged between the restraint plates 16A and 16B and the conductive plate 14. Each of the restraint plates 16A and 16B is made of a metal such as iron. When viewed from the stacking direction, the restraint plates 16A and 16B and the insulating film 22 have, for example, a rectangular shape. The insulating film 22 is larger than the conductive plate 14, and the restraint plates 16A and 16B are larger than the size in which the power storage modules 12 are arranged in parallel. When viewed from the stacking direction, an insertion hole 16A1 through which the shaft portion of the bolt 18 is inserted is provided at a position outside the power storage module 12 at the edge portion of the restraint plate 16A. Similarly, when viewed from the stacking direction, an insertion hole 16B1 through which the shaft portion of the bolt 18 is inserted is provided at a position outside the power storage module 12 at the edge portion of the restraint plate 16B. When the restraint plates 16A and 16B have a rectangular shape when viewed from the stacking direction, the insertion holes 16A1 and the insertion holes 16B1 are located at the corners of the restraint plates 16A and 16B.

One restraint plate 16A is abutted against the conductive plate 14 constituting the negative electrode current collector 61 via an insulating film 22, and the other restraint plate 16B is an insulating film against the conductive plate 14 constituting the positive electrode current collector 62. It is struck through 22. For example, the bolt 18 is passed through the insertion hole 16A1 from one restraint plate 16A side toward the other restraint plate 16B side, and a nut 20 is screwed into the tip of the bolt 18 protruding from the other restraint plate 16B. There is. As a result, the insulating film 22, the conductive plate 14, and the power storage module 12 are sandwiched and unitized, and a restraining load is applied in the stacking direction.

FIG. 2 is a schematic cross-sectional view showing a power storage module constituting the power storage device of FIG. The power storage module 12 shown in the figure includes a laminated body 30 in which a plurality of bipolar electrodes 32 are laminated. The laminated body 30 has, for example, a rectangular shape when viewed from the stacking direction of the bipolar electrodes 32. A separator 40 may be arranged between adjacent bipolar electrodes 32. The bipolar electrode 32 includes an electrode plate 34, a positive electrode 36 provided on one surface of the electrode plate 34, and a negative electrode 38 provided on the other surface of the electrode plate 34. In the laminated body 30, the positive electrode 36 of one bipolar electrode 32 faces the negative electrode 38 of one of the bipolar electrodes 32 adjacent to each other in the stacking direction with the separator 40 interposed therebetween, and the negative electrode 38 of one bipolar electrode 32 has the separator 40. It faces the positive electrode 36 of the other bipolar electrode 32 that is adjacent to each other in the stacking direction. In the stacking direction, an electrode plate 34 (negative electrode side terminal electrode) having a negative electrode 38 arranged on the inner side surface is arranged at one end of the laminated body 30, and an electrode plate having a positive electrode 36 arranged on the inner side surface at the other end. 34 (positive electrode side terminal electrode) is arranged. The negative electrode 38 of the negative electrode side terminal electrode faces the positive electrode 36 of the uppermost bipolar electrode 32 via the separator 40. The positive electrode 36 of the positive electrode side terminal electrode faces the negative electrode 38 of the lowermost bipolar electrode 32 via the separator 40. The electrode plates 34 of these terminal electrodes are connected to adjacent conductive plates 14 (see FIG. 1).

The power storage module 12 includes a frame body 50 that holds the edge portion 34a of the electrode plate 34 on the side surface 30a of the laminated body 30 extending in the stacking direction of the bipolar electrodes 32. The frame body 50 is configured to surround the side surface 30a of the laminated body 30. The side surface 50s has, for example, a rectangular shape when viewed from the stacking direction of the bipolar electrodes 32. In this case, the side surface 50s is composed of four rectangular surfaces. The frame body 50 may include a first resin portion 52 that holds the edge portion 34a of the electrode plate 34, and a second resin portion 54 that is provided around the first resin portion 52 when viewed from the stacking direction.

The first resin portion 52 constituting the inner wall of the frame body 50 is provided from one surface (the surface on which the positive electrode 36 is formed) of the electrode plate 34 of each bipolar electrode 32 to the end surface of the electrode plate 34 at the edge portion 34a. .. When viewed from the stacking direction of the bipolar electrodes 32, each first resin portion 52 is provided over the entire circumference of the edge portion 34a of the electrode plate 34 of each bipolar electrode 32. The adjacent first resin portions 52 are welded to each other on a surface extending outside the other surface (the surface on which the negative electrode 38 is formed) of the electrode plate 34 of each bipolar electrode 32. As a result, the edge portion 34a of the electrode plate 34 of each bipolar electrode 32 is buried and held in the first resin portion 52. Similar to the edge 34a of the electrode plate 34 of each bipolar electrode 32, the edge 34a of the electrode plates 34 arranged at both ends of the laminated body 30 is also held in a state of being embedded in the first resin portion 52. As a result, an internal space V airtightly partitioned by the electrode plates 34, 34 and the first resin portion 52 is formed between the electrode plates 34, 34 adjacent to each other in the stacking direction. An electrolytic solution (not shown) composed of an alkaline solution such as an aqueous potassium hydroxide solution is housed in the internal space V.

The second resin portion 54 constituting the outer wall of the frame body 50 is a tubular portion extending over the entire length of the laminated body 30 in the stacking direction of the bipolar electrode 32. The second resin portion 54 covers the outer surface of the first resin portion 52 extending in the stacking direction of the bipolar electrode 32. The second resin portion 54 is welded to the outer surface of the first resin portion 52 on the inner surface extending in the stacking direction of the bipolar electrode 32.

The electrode plate 34 is a rectangular metal leaf made of, for example, nickel. The edge portion 34a of the electrode plate 34 is an uncoated region in which the positive electrode active material and the negative electrode active material are not coated, and the uncoated region is buried in the first resin portion 52 constituting the inner wall of the frame body 50. It is an area that is held. Examples of the positive electrode active material constituting the positive electrode 36 include nickel hydroxide. Examples of the negative electrode active material constituting the negative electrode 38 include a hydrogen storage alloy. The formation region of the negative electrode 38 on the other surface of the electrode plate 34 is slightly larger than the formation region of the positive electrode 36 on one surface of the electrode plate 34.

The separator 40 is formed in a sheet shape, for example. Examples of the material for forming the separator 40 include a porous film made of a polyolefin resin such as polyethylene (PE) and polypropylene (PP), a woven fabric made of polypropylene or the like, or a non-woven fabric. Further, the separator 40 may be reinforced with a vinylidene fluoride resin compound or the like.

The frame body 50 (first resin portion 52 and second resin portion 54) is formed in a rectangular tubular shape by, for example, injection molding using an insulating resin. Examples of the resin material constituting the frame 50 include polypropylene (PP), polyphenylene sulfide (PPS), modified polyphenylene ether (modified PPE), and the like.

Returning to FIG. 1, the connection relationship of each component of the power storage device 10 will be described in more detail.

In the power storage device 10, on one side (negative side) of the restraint plates 16A and 16B in the X direction, the power storage modules 12A, 12B and 12C constituting the first power generation unit 63A and the conductive plates 14A, 14B, 14C and 14D , Are stacked alternately. Specifically, the conductive plate 14A is arranged between the restraint plate 16A and the power storage module 12A. A conductive plate 14B is arranged between the power storage module 12A and the power storage module 12B. A conductive plate 14C is arranged between the power storage module 12B and the power storage module 12C. A conductive plate 14D is arranged between the power storage module 12C and the restraint plate 16B.

On the other side (positive side) of the restraint plates 16A and 16B in the X direction, the power storage modules 12D, 12E and 12F constituting the second power generation unit 63B and the conductive plates 14E, 14F, 14G and 14H are alternately laminated. Has been done. Specifically, the conductive plate 14E is arranged between the restraint plate 16A and the power storage module 12D. A conductive plate 14F is arranged between the power storage module 12D and the power storage module 12E. A conductive plate 14G is arranged between the power storage module 12E and the power storage module 12F. A conductive plate 14H is arranged between the power storage module 12F and the restraint plate 16B.

The conductive plate 14A and the conductive plate 14E are electrically connected by the connecting portion 15A. Further, the negative electrode terminal 26 is pulled out from the conductive plate 14E. As a result, the negative electrode current collector 61 is configured by the conductive plates 14A and 14E and the connecting portion 15A. That is, the negative electrode current collecting unit 61 is conductive with a conductive plate 14A connected to the power storage module 12A of the first power generation unit 63A in the stacking direction, 14E connected to the power storage module 12D of the second power generation unit 63B in the stacking direction, and the like. It is configured to include a connecting portion 15A that electrically connects the plate 14A and the conductive plate 14E.

The conductive plate 14D and the conductive plate 14H are electrically connected by the connecting portion 15B. Further, the positive electrode terminal 24 is pulled out from the conductive plate 14H. As a result, the positive electrode terminal 24 is configured by the conductive plates 14D and 14H and the connecting portion 15B. That is, the positive electrode current collecting unit 62 is conductive with a conductive plate 14D connected to the power storage module 12C of the first power generation unit 63A in the stacking direction, and 14H connected to the power storage module 12F of the second power generation unit 63F in the stacking direction. It is configured to include a connecting portion 15B that electrically connects the plate 14D and the conductive plate 14H.

The conductive plate 14B and the conductive plate 14F are electrically connected by the connecting portion 15C. As a result, the relay current collecting unit 64 is configured by the conductive plates 14B and 14F and the connecting unit 15C. That is, the relay current collector 64 includes a conductive plate 14B laminated on the power storage modules 12A and 12B of the first power generation unit 63A, a conductive plate 14F laminated on the power storage modules 12D and 12E of the second power generation unit 63B, and conductivity. It is configured to include a connecting portion 15C that electrically connects the plate 14B and the conductive plate 14F.

The conductive plate 14C and the conductive plate 14G are electrically connected by the connecting portion 15D. As a result, the relay current collector 65 is configured by the conductive plates 14C and 14G and the connecting portion 15D. That is, the relay current collecting unit 65 includes a conductive plate 14C laminated on the power storage modules 12B and 12C of the first power generation unit 63A, a conductive plate 14G laminated on the power storage modules 12E and 12F of the second power generation unit 63B, and conductivity. It is configured to include a connecting portion 15D that electrically connects the plate 14C and the conductive plate 14G.

The connecting portions 15A, 15B, 15C and 15D have a solid configuration. That is, the connecting portions 15A, 15B, 15C, and 15D are not formed with voids for the refrigerant unlike the conductive plates. In the example shown in FIG. 1, the connecting portions 15A, 15B, 15C, and 15D are thinner (size in the Z direction) than the respective conductive plates, but the thickness is the same as that of the respective conductive plates. Good. Further, the positions of the connecting portions 15A, 15B, 15C, and 15D in the thickness direction with respect to the conductive plates are not particularly limited. Further, the size of the connecting portions 15A, 15B, 15C, and 15D in the Y direction may be smaller than that of each electrode plate, but may be the same size as the conductive plate. Further, the connecting portions 15A, 15B, 15C and 15D may be divided into a plurality of portions in the Y direction. Further, the connecting portions 15A, 15B, 15C and 15D may be formed of a plate-shaped member or may be formed of a linear member such as a wire. Further, the connecting portions 15A, 15B, 15C, and 15D may be configured by connecting another member to the corresponding conductive plate 14, but may be integrally configured with the corresponding conductive plate 14. Further, the connecting portion, the conductive plate 14 corresponding to the first power generation unit 63A, and the conductive plate 14 corresponding to the second power generation unit 63B may be configured as one plate.

Voltage monitoring units 70A, 70B, 70C, and 70D for monitoring voltage are connected to the negative electrode current collector 61, the positive electrode current collector 62, and the relay current collectors 64, 65, respectively. A voltage monitoring unit 70A is connected to the negative electrode current collector 61 via the negative electrode terminal 26. A voltage monitoring unit 70B is connected to the positive electrode current collector 62 via the positive electrode terminal 24. A voltage monitoring unit 70C is connected to the relay current collecting unit 64 at the position of the connection unit 15C. A voltage monitoring unit 70D is connected to the relay current collecting unit 65 at the position of the connection unit 15D. The voltage monitoring units 70A, 70B, 70C, and 70D may be connected to any position in each current collector.

With the above configuration, the circuit configuration as shown in FIG. 4A is established. As shown in FIG. 4A, the power storage modules 12A, 12B, and 12D are connected in series in the first power generation unit 63A, and the power storage modules 12D, 12E, and 12F are connected in series in the second power generation unit 63B. There is. Further, the first power generation unit 63A and the second power generation unit 63B are connected by relay current collectors 64 and 65.

Next, the operation / effect of the power storage device 10 according to the present embodiment will be described.

First, the power storage device 100 according to the comparative example will be described with reference to FIGS. 3 and 4B. The power storage device 100 according to the comparative example is not provided with connection parts 15C and 15D such as the relay current collectors 64 and 65 of the power storage device 10 according to the present embodiment. That is, the conductive plate laminated on the first power generation unit 63A and the conductive plate laminated on the second power generation unit 63B are not electrically connected and are electrically independent of each other. Therefore, it is necessary to provide one voltage monitoring unit 70 for each of the conductive plate laminated on the first power generation unit 63A and the conductive plate laminated on the second power generation unit 63B. Specifically, the voltage monitoring unit 70E is provided on the conductive plate 14B laminated on the first power generation unit 63A, and the voltage monitoring unit 70G is provided on the conductive plate 14F laminated on the second power generation unit 63B. The voltage monitoring unit 70F is provided on the conductive plate 14C laminated on the first power generation unit 63A, and the voltage monitoring unit 70H is provided on the conductive plate 14G laminated on the second power generation unit 63B. As described above, in the power storage device 100, as the number of parallel power generation units increases, it is necessary to provide the voltage monitoring unit 70 for the conductive plate 14 of each power generation unit, so that the number of voltage monitoring units 70 increases. It ends up. In particular, when the number of parallel power generation units (for example, N) is large, the number of required voltage monitoring units 70 increases by N even if the number of stacked power storage modules in each power generation unit increases by one. In this way, the number of voltage monitoring units 70 in the power storage device 100 increases, and the cost increases.

On the other hand, in the power storage device 10 according to the present embodiment, at least the first power generation unit 63A and the second power generation unit 63B are connected in parallel to the negative electrode current collector 61 and the positive electrode current collector 62. The first power generation unit 63A and the second power generation unit 63B include a plurality of power storage modules 12 stacked via relay current collection units 64 and 65. In the power storage device 10 having such a configuration, the relay current collection units 64 and 65 are the conductive plates 14B and 14C (first conductive plate) laminated on the power storage module 12 of the first power generation unit 63A and the second power generation unit. A conductive plate 14F, 14G (second conductive plate) laminated on the power storage module 12 of 63B, and connecting portions 15C, 15D for electrically connecting the conductive plates 14B, 14C and the conductive plates 14F, 14G are provided. There is. In this way, the first power generation unit 63A and the second power generation unit 63B, which are connected in parallel, are electrically connected via the relay current collectors 64, 65, so that the relay current collectors 64, 65 Voltages are equal to each other. Therefore, in the present embodiment, the voltage monitoring units 70C and 70D connected to the relay current collecting units 64 and 65 can simultaneously monitor the voltages of the first power generation unit 63A and the second power generation unit 63B at the positions. .. That is, since it is not necessary to provide the voltage monitoring unit 70 in each of the first power generation unit 63A and the second power generation unit 63, the number of required voltage monitoring units 70 can be reduced. As described above, when the power storage modules 12 are provided in parallel, it is possible to suppress an increase in the number of voltage monitoring units 70 provided in the power storage device 10. In particular, when the number of parallel power generation units (for example, N) is large, if the number of stacked power storage modules in each power generation unit increases by one, the required voltage monitoring unit 70 only increases by one.

The conductive plates 14B and 14C and the conductive plates 14F and 14G of the relay current collectors 64 and 65 are provided with voids 14a through which the refrigerant passes. As a result, the conductive plates 14B, 14C, 14F, and 14G also have a function as a cooling plate for cooling the power storage module 12.

The connection units 15C and 15D of the relay current collector units 64 and 65 have a solid configuration. The connection portions 15C and 15D are provided at positions different from those of the power storage module 12. Even if the connecting portions 15C and 15D are provided with voids through which the refrigerant passes, the cooling efficiency is low. Therefore, by forming the connecting portions 15C and 15D with a solid structure without providing voids, it is possible to suppress the flow of the refrigerant to a portion having low cooling efficiency.

The frame body 50 includes a plurality of first resin portions 52 for holding the edges of the electrode plate 34, and a second resin portion 54 provided around the first resin portion 52 when viewed from the stacking direction. .. Thereby, the sealing property of the power storage module 12 can be improved.

The voltage monitoring unit 70 is connected to the relay current collecting units 64 and 65. The voltage monitoring units 70C and 70D connected to the relay current collecting units 64 and 65 can simultaneously monitor the voltages of the first power generation unit 63A and the second power generation unit 63B at the positions. That is, since it is not necessary to provide the voltage monitoring unit 70 in each of the first power generation unit 63A and the second power generation unit 63B, the number of required voltage monitoring units 70 can be reduced.

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

For example, in the above-described embodiment, the voltage monitoring unit 70 is provided for both the relay current collecting units 64 and 65, but the voltage monitoring unit 70 may be omitted from one of the relay current collecting units. Alternatively, the voltage monitoring unit 70 connected to the relay current collecting units 64 and 65 may be omitted. That is, by adopting the relay current collectors 64 and 65, the voltages of the first power generation unit 63A and the second power generation unit 63B become equal, so that the voltage monitoring unit 70 at the relay position in each power generation unit is omitted and the negative electrode is used. The voltage may be monitored only by the voltage monitoring unit 70 connected to the current collecting unit 61 and the positive electrode current collecting unit 62.

For example, the number of parallel power generation units of the power storage device was two in the above-described embodiment, but may be three or more. Further, although the number of stacked power storage modules of the power generation unit per one is three, it may be two or four or more.

12 ... Power storage module, 14B, 14C ... Conductive plate (first conductive plate), 14F, 14G ... Conductive plate (second conductive plate), 15C, 15D ... Connection part, 30 ... Laminated body, 30a ... Side surface, 32 ... Bipolar Electrode, 34 ... Electrode plate, 34a ... Edge, 36 ... Positive electrode, 38 ... Negative electrode, 50 ... Frame, 52 ... 1st resin part, 54 ... 2nd resin part, 61 ... Negative electrode current collector, 62 ... Positive electrode collection Electric unit, 63A ... 1st power generation unit, 63B ... 2nd power generation unit, 64, 65 ... Relay current collection unit, 70 ... Voltage monitoring unit.

Claims (4)

A negative electrode current collector electrically connected to the negative electrode terminal,
A positive electrode current collector electrically connected to the positive electrode terminal,
At least the first power generation unit and the second power generation unit connected in parallel to the negative electrode current collector and the positive electrode current collector,
A power storage device including a voltage monitoring unit that monitors voltage.
The first power generation unit and the second power generation unit include a plurality of power storage modules stacked via a relay current collector.
The power storage module
A laminate in which a plurality of bipolar electrodes including an electrode plate, a positive electrode provided on one surface of the electrode plate, and a negative electrode provided on the other surface of the electrode plate are laminated.
A frame body that holds an edge of the electrode plate on a side surface of the laminated body extending in the stacking direction of the bipolar electrodes is provided.
The first power generation unit and the second power generation unit each include N (where N is an integer of 2 or more) of the power storage modules and N-1 of the relay current collectors.
The n-th relay current collector (where n is an integer of 1 or more and N-1 or less) among the N-1 relay current collectors is
The n-th first conductive plate laminated between the n-th storage module and the n + 1-th power storage module counted from the negative electrode current collector side to the positive electrode current collector side of the first power generation unit. When,
The n-th second conductive plate laminated between the n-th storage module and the n + 1-th power storage module counted from the negative electrode current collector side to the positive electrode current collector side of the second power generation unit. When,
comprising the n-th of the first conductive plate and the n-th of the connecting portion and a second conductive plate electrically connected, and
Before SL voltage monitoring unit, the negative electrode current collecting portion, the positive electrode current collector, and are respectively connected to the N-1 of the relay current collector,
One voltage monitoring unit is connected to one relay current collector,
A power storage device in which a gap through which a refrigerant passes is provided in the first conductive plate and the second conductive plate of the relay current collector. The power storage device according to claim 1, wherein the power storage module has voltage extraction units at both ends in the stacking direction. The power storage device according to claim 1 or 2, wherein the connection portion of the relay current collector has a solid configuration. The frame is
A plurality of first resin portions that hold the edge portion of the electrode plate, and
The power storage device according to any one of claims 1 to 3, further comprising a second resin portion provided around the first resin portion when viewed from the stacking direction.

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