JP2015041595A - Power storage device - Google Patents

Abstract

Disposing a duct between a power storage element and a substrate tends to cause a dead space between the power storage element and the substrate. A power storage device (1) has a plurality of power storage elements (10) arranged side by side in a predetermined direction (X direction). Each storage element has a valve (13) for discharging gas generated inside the storage element to the outside of the storage element. A bus bar (31) is connected to the electrode terminals (11, 12) of each power storage element, and the plurality of power storage elements are electrically connected by the bus bar. The electrode terminal penetrates the board (40) on which the electronic component is mounted, and the board has an opening (41) through which the gas discharged from the valve passes. The power storage device has a duct (50) into which gas passing through the opening of the substrate enters, and the duct is arranged at a position apart from the electrode terminal protruding from the substrate. [Selection diagram]

Description

  The present invention relates to a power storage device having a plurality of power storage elements, and having a structure for discharging gas from a valve of each power storage element.

  Patent Document 1 describes a battery block in which a plurality of battery cells are stacked. Here, a discharge port of a safety valve is provided on the upper surface of each battery cell, and a gas discharge duct is disposed above the discharge ports of the plurality of battery cells. The gas discharge duct is used to guide the gas discharged from the discharge port to a position away from the battery block.

  Moreover, in patent document 1, the circuit board with which the electronic component was mounted is arrange | positioned on the upper surface of a battery block. Here, a gas discharge duct is disposed between the circuit board and each battery cell.

JP 2010-080135 A International Publication No. 2012/029317 Pamphlet

  In Patent Document 1, since a gas discharge duct is disposed between the circuit board and each battery cell, a dead space is likely to occur between the circuit board and each battery cell. In order to easily discharge the gas from the discharge port, it is difficult to reduce the size of the gas discharge duct. Therefore, a dead space is easily generated between the circuit board and each battery cell.

  The power storage device of the present invention has a plurality of power storage elements arranged side by side in a predetermined direction. Each power storage element has a valve that discharges gas generated inside the power storage element to the outside of the power storage element. A bus bar is connected to the electrode terminal of each power storage element, and a plurality of power storage elements are electrically connected by the bus bar.

  The electrode terminal passes through a substrate on which electronic components are mounted, and an opening for allowing the gas discharged from the valve to pass through is formed in the substrate. The power storage device has a duct into which the gas that has passed through the opening of the substrate enters, and the duct is disposed at a position away from the electrode terminal protruding from the substrate.

  According to the present invention, the substrate can be disposed between the duct and the power storage element, and the substrate can be brought close to the power storage element. Thereby, while being able to discharge gas using a duct, the dead space which generate | occur | produces between an electrical storage element and a board | substrate can be reduced. Moreover, a duct can be arrange | positioned, without interfering with the electrode terminal which protrudes from a board | substrate.

It is an external view of a battery stack. It is the external view which decomposed | disassembled some battery stacks. It is a bottom view of a duct. It is a figure which shows the structure which discharges | emits the gas from a cell.

  Examples of the present invention will be described below.

  A battery stack (corresponding to the power storage device of the present invention) that is Example 1 will be described. FIG. 1 is an external view of the battery stack, and FIG. 2 is an external view when a part of the battery stack is disassembled. 1 and 2, an X axis, a Y axis, and a Z axis are orthogonal to each other. In this embodiment, an axis corresponding to the vertical direction (vertical direction) is a Z axis. The relationship among the X axis, the Y axis, and the Z axis is the same in other drawings.

  The battery stack 1 shown in FIGS. 1 and 2 can be mounted on a vehicle. The battery stack 1 has a plurality of single cells (corresponding to the power storage device of the present invention) 10 arranged side by side in the X direction, and the plurality of single cells 10 serves as a power source for running the vehicle. Can be used. As the unit cell 10, a secondary battery such as a nickel metal hydride battery or a lithium ion battery can be used. An electric double layer capacitor can be used instead of the secondary battery. The unit cell 10 is a so-called prismatic cell, and the outer shape of the unit cell 10 is formed in a shape along a rectangular parallelepiped.

  A positive electrode terminal (also referred to as an electrode terminal) 11 and a negative electrode terminal (also referred to as an electrode terminal) 12 are provided on the upper surface of the unit cell 10, and the electrode terminals 11 and 12 are directed upward from the upper surface of the unit cell 10. It protrudes. A power generation element (not shown) that charges and discharges is accommodated inside the unit cell 10. As is well known, the power generation element includes a positive electrode plate, a negative electrode plate, and a separator disposed between the positive electrode plate and the negative electrode plate. The positive electrode terminal 11 is electrically connected to the positive electrode plate of the power generation element, and the negative electrode terminal 12 is electrically connected to the negative electrode plate of the power generation element.

  A valve 13 is provided on the upper surface of the unit cell 10. The valve 13 is used to discharge gas generated inside the unit cell 10 to the outside of the unit cell 10. The valve 13 is located between the positive electrode terminal 11 and the negative electrode terminal 12 in the Y direction.

  For example, if the unit cell 10 (power generation element) is overcharged, gas may be generated from the power generation element (mainly electrolyte). Since the inside of the unit cell 10 is in a sealed state, the pressure (internal pressure) inside the unit cell 10 increases with the generation of gas. When the internal pressure of the unit cell 10 reaches the operating pressure of the valve 13, the valve 13 changes from a closed state to an open state, thereby discharging gas to the outside of the unit cell 10.

  In the present embodiment, the plurality of single cells 10 are arranged in the X direction, but the present invention is not limited to this. Specifically, a battery module can be used in place of the unit cell 10, and a plurality of battery modules can be arranged in the X direction. The battery module has a plurality of power generation elements electrically connected in series.

  A partition plate 21 is disposed between two unit cells 10 adjacent in the X direction. The partition plate 21 can be formed of an insulating material such as a resin, for example, and the two unit cells 10 sandwiching the partition plate 21 can be in an insulated state. Ribs (not shown) protruding in the X direction are formed on the side surface of the partition plate 21 facing the unit cell 10 in the X direction. A space is formed between the unit cell 10 and the partition plate 21 by the tips of the ribs coming into contact with the outer surface of the unit cell 10. This space is a space where a heat exchange medium (gas or liquid) used for adjusting the temperature of the unit cell 10 moves.

  A pair of end plates 22 are disposed at both ends of the battery stack 1 in the X direction. Both ends of a restraining band 23 extending in the X direction are fixed to the pair of end plates 22. By fixing both ends of the restraining band 23 to the pair of end plates 22, the pair of end plates 22 can be displaced in a direction approaching each other (X direction), and a plurality of single cells sandwiched between the pair of end plates 22. A restraining force can be applied to 10.

  In FIG. 1 and FIG. 2, only the restraint band 23 arrange | positioned at the lower surface of the battery stack 1 is shown. A restraining band 23 is also disposed on the upper surface of the battery stack 1. Here, the restraint band 23 may be fixed to the pair of end plates 22 and the restraint force may be applied to the plurality of single cells 10, and the position where the restraint band 23 is disposed can be set as appropriate.

  A bus bar 31 is disposed on the upper surface of the unit cell 10. The bus bar 31 is used to electrically connect two unit cells 10 adjacent in the X direction in series or to connect a cable connected to a load to the electrode terminals 11 and 12. Here, the electrode terminals 11 and 12 connected to the cable are the positive terminal 11 of the unit cell 10 arranged at one end of the battery stack 1 in the X direction and the unit arranged at the other end of the battery stack 1 in the X direction. This is a negative electrode terminal 12 of the battery 10.

  An opening is formed in the bus bar 31, and the electrode terminals 11 and 12 penetrate the opening of the bus bar 31. A connection ring 32 is attached to the electrode terminals 11 and 12 penetrating through the opening of the bus bar 31. A nut may be used in place of the connection ring 32 and the nut may be fastened to the electrode terminals 11 and 12. When nuts are fastened to the electrode terminals 11 and 12, the bus bar 31 can be pressed against the base end portions of the electrode terminals 11 and 12. When using nuts, screw grooves may be formed in the electrode terminals 11 and 12. Also, a washer can be used together with the nut.

  A substrate 40 is disposed on the upper surface of the unit cell 10. Here, a bus bar 31 and a connection ring 32 are arranged between the upper surface of the unit cell 10 and the substrate 40. The substrate 40 is formed with an opening for penetrating the electrode terminals 11 and 12. The electrode terminals 11 and 12 that pass through the bus bar 31 and the connection ring 32 pass through the opening of the substrate 40, and the tips of the electrode terminals 11 and 12 protrude upward from the upper surface of the substrate 40.

  A nut 33 is fastened to the electrode terminals 11 and 12 protruding from the upper surface of the substrate 40. Since the threaded grooves are formed in the electrode terminals 11 and 12, the nut 33 can be fastened to the electrode terminals 11 and 12. By using the nut 33, the substrate 40 can be pressed against the unit cell 10 to fix the substrate 40 to the unit cell 10. Further, the bus bar 31 disposed between the substrate 40 and the unit cell 10 can be pressed against the unit cell 10 by pressing the substrate 40 toward the unit cell 10. A washer can be used together with the nut 33.

  Electronic components and wiring are mounted on the substrate 40. The electronic component and the wiring can be disposed on at least one of the upper surface and the lower surface of the substrate 40. Examples of the electronic component include a fuse, a resistor, a Zener diode, a capacitor, a thermistor, and a monitoring IC (Integrated Circuit). The monitoring IC is connected to the electrode terminals 11 and 12 through wiring, and is used to detect the voltage value of each unit cell 10. As the board | substrate 40, the printed circuit board (for example, flexible printed circuit board) by which wiring was printed can be used.

  The substrate 40 has an opening 41, and the openings 41 are provided as many as the number of unit cells 10. The plurality of openings 41 are arranged side by side in the X direction. Each opening 41 faces the valve 13 of each unit cell 10 in the Z direction. When gas is discharged from the valve 13, this gas passes through the opening 41.

  In the present embodiment, the same number of openings 41 as the number of unit cells 10 are provided in the substrate 40, but the present invention is not limited to this. That is, the opening 41 only needs to allow the gas discharged from the valve 13 to pass therethrough, and the number of openings 41 can be set as appropriate. If the opening area of the opening 41 is appropriately set, one opening 41 can be provided for the valves 13 of at least two unit cells 10.

  The length (width) of the substrate 40 in the Y direction is longer than the distance between the positive terminal 11 and the negative terminal 12 in each unit cell 10. By using such a substrate 40, the mounting area of the electronic component can be increased and the electronic component can be easily mounted. Further, by forming the opening 41 in such a substrate 40, it is possible to suppress the gas discharged from the valve 13 from colliding with the substrate 40. Here, although the gas discharged from the valve 13 is in a high temperature state, if the substrate 40 is formed using a heat resistant material such as glass epoxy resin, the substrate 40 can have heat resistance performance against the gas in the high temperature state. it can.

  Here, the area of the opening 41 in the XY plane can be made larger than the area of the valve 13 in the XY plane. This makes it difficult for the gas discharged from the valve 13 to collide with the substrate 40. However, since the opening 41 only needs to allow the gas discharged from the valve 13 to pass therethrough, the area and shape of the opening 41 in the XY plane can be set as appropriate.

  A duct 50 extending in the X direction is disposed on the upper surface of the substrate 40, and the bottom surface of the duct 50 is in contact with the upper surface of the substrate 40. The duct 50 is used to move the gas discharged from the valve 13 of the unit cell 10 in a direction away from the battery stack 1. For example, when the battery stack 1 is mounted on a vehicle, the gas discharged from the valve 13 can be discharged outside the vehicle by using the duct 50.

  Here, another duct (not shown) can be connected to the duct 50 shown in FIGS. 1 and 2. In FIG. 2, the direction in which gas is discharged in the duct 50 is indicated by arrows. As shown in FIG. 1, the duct 50 is disposed between the positive electrode terminal 11 and the negative electrode terminal 12 in each unit cell 10, and is separated from the electrode terminals 11 and 12 and the nut 33. Thereby, the duct 50 can be disposed without interfering with the electrode terminals 11 and 12 and the nut 33.

  As shown in FIG. 3, a plurality of openings 51 are formed in the duct 50. FIG. 3 is a schematic view when the duct 50 is viewed from the substrate 40 side. The plurality of openings 51 are arranged in the longitudinal direction (X direction) of the duct 50. The number of openings 51 may be the same as or different from the number of openings 41 in the substrate 40. The opening 51 only needs to allow the gas that has passed through the opening 41 of the substrate 40 to enter the inside of the duct 50, and at least one opening 51 can be provided in the duct 50.

  As shown in FIG. 4, a seal member 52 can be disposed between the substrate 40 and the upper surface of the unit cell 10. The seal member 52 can be provided at a position surrounding the valve 13 and the opening 41 in the XY plane. By using the seal member 52, the gas discharged from the valve 13 can be easily guided to the opening 41. Here, since the gas discharged from the valve 13 is in a high temperature state, it is preferable to use a heat resistant material as the seal member 52. In addition, if the board | substrate 40 is made to contact the outer surface (upper surface) of the cell 10 in which the valve 13 was provided, the sealing member 52 can also be abbreviate | omitted.

  According to the present embodiment, by arranging the substrate 40 between the upper surface of the unit cell 10 and the duct 50, the substrate 40 can be disposed close to the unit cell 10 side. Thereby, the dead space which generate | occur | produces between the upper surface of the cell 10 and the board | substrate 40 can be reduced. And the gas discharged | emitted from the valve 13 can be guide | induced to the position away from the battery stack 1 using the duct 50 arrange | positioned at the upper surface of the board | substrate 40. FIG.

  In the present embodiment, the bus bar 31 is disposed between the upper surface of the unit cell 10 and the substrate 40, but the bus bar 31 may be disposed on the upper surface of the substrate 40. In this case, the bus bar 31 can be fixed to the electrode terminals 11, 12 and the substrate 40 using the nut 33.

1: battery stack, 10: single cell, 11: positive electrode terminal (electrode terminal),
12: Negative terminal (electrode terminal), 13: Valve, 21: Partition plate, 22: End plate,
23: Restraint band, 31: Bus bar, 32: Connection ring, 33: Nut, 40: Board
41: opening, 50: duct, 51: opening, 52: seal member

Claims (1)

Each having a valve for discharging gas, a plurality of power storage elements arranged side by side in a predetermined direction;
A bus bar connected to the electrode terminals of each of the storage elements, and electrically connecting the plurality of storage elements;
A substrate having an opening through which the electrode terminal penetrates and an electronic component is mounted, and through which the gas discharged from the valve passes,
A duct that is disposed at a position away from the electrode terminal protruding from the substrate and into which the gas that has passed through the opening enters,
A power storage device comprising: