JP2023067618A - power storage device - Google Patents

Abstract

To provide a power storage device with a simple configuration and improved safety.SOLUTION: A power storage device 1 includes a plurality of power storage elements 100, a gas discharge path forming member 250 forming a gas discharge path 254, and a partition wall portion 155. Each of the plurality of power storage elements 100 has a gas discharge valve 105 facing in a positive direction of a Z-axis, and they are arranged in an X-axis direction. The gas discharge path forming member 250 is arranged to face the plurality of gas discharge valves 105 in a positive direction of the Z-axis. The partition wall portion 155 is arranged between the gas discharge valves 105 of two adjacent power storage elements 100 among the plurality of power storage elements 100 when viewed from the positive direction of the Z-axis, and partitions two or more of the gas discharge paths 254 in the X-axis direction. The gas discharge path forming member 250 has a discharge portion 255 for discharging gas from the inside of the gas discharge path forming member 250 to the outside.SELECTED DRAWING: Figure 4

Description

The present invention relates to a power storage device.

Patent Literature 1 discloses an assembled battery (power storage device) including a plurality of batteries (power storage elements). In this assembled battery, each of the plurality of batteries is held by a battery holder. The battery holder includes a main body member that contacts the wide surface of the battery container, and an upper member that has one end fixed to the upper end of the main body member and the other end that contacts the upper surface of the battery container and extends in the thickness direction of the battery. The upper member is formed so as to surround the gas discharge valve of the battery and is in contact with the lower surface of the gas pipe member to form a gas flow path from the gas discharge valve to the gas pipe member.

WO2015/079430

2. Description of the Related Art In a power storage device included in a power storage device, when an abnormal external force acts on the power storage device, which is not a normally foreseen usage pattern, the temperature inside the power storage device may rise and gas may be generated. Since the generation of gas may increase the internal pressure of the storage element, the storage element includes a gas discharge valve that opens to release the internal gas when the internal pressure of the storage element rises above a predetermined pressure. In the conventional power storage device (battery assembly) disclosed in Patent Document 1, a gas pipeline member is arranged at a position facing a gas discharge valve of a plurality of power storage elements (batteries) arranged in a row. When the gas is discharged from the gas discharge valve of the storage element, the gas is guided into the gas pipeline member by the upper member arranged so as to surround the gas discharge valve. In this case, the pressure of the gas discharged from the gas discharge valve of one storage element among the plurality of storage elements is transmitted to all the other storage elements via the gas pipeline member forming one gas discharge path. can affect Specifically, the pressure of the gas discharged from the gas discharge valve of one storage element causes the gas discharge valve of another storage element to open (open), and the electrolyte inside the storage element leaks to the outside. there's a possibility that. In order to solve this problem, it is conceivable to dispose a member (exhaust pipe, etc.) that forms an individual gas discharge path for each of the plurality of gas discharge valves. However, in this case, there arises another problem that the configuration of the power storage device becomes complicated.

SUMMARY OF THE INVENTION The present invention has been made by the inventors of the present invention by focusing on the above problems, and an object of the present invention is to provide a power storage device having a relatively simple configuration and improved safety.

A power storage device according to an aspect of the present invention includes a power storage element, a plurality of power storage elements each having a gas discharge valve facing a first direction, and arranged in a second direction that intersects with the first direction; A gas discharge path forming member that forms a gas discharge path and is arranged to face the plurality of gas discharge valves in the first direction; a partition wall disposed between the gas discharge valves of the two storage elements and partitioning the gas discharge path into two or more in the second direction, wherein the gas discharge path forming member is positioned inside the gas discharge path forming member. It has an exhaust part for exhausting gas from.

According to the present invention, it is possible to provide a power storage device with a relatively simple configuration and improved safety.

1 is a perspective view showing an appearance of a power storage device according to an embodiment; FIG. 1 is an exploded perspective view of a power storage device according to an embodiment; FIG. 1 is a perspective view showing the appearance of a power storage device according to an embodiment; FIG. 1 is an exploded perspective view of a power storage element unit according to an embodiment; FIG. 1 is an exploded perspective view of a storage element array according to an embodiment; FIG. FIG. 2 is a perspective cross-sectional view of a gas discharge path forming member according to an embodiment; FIG. 4 is a schematic diagram showing the position of the partition wall inside the gas discharge path forming member according to the embodiment; FIG. 4 is a perspective cross-sectional view showing a structural relationship between a gas discharge path forming member and a partition wall portion according to the embodiment;

A power storage device according to an aspect of the present invention includes a plurality of power storage elements each having a gas discharge valve facing a first direction and arranged in a second direction that intersects with the first direction; a gas discharge path forming member arranged to face the plurality of gas discharge valves and forming a gas discharge path; and two adjacent storage elements among the plurality of storage elements when viewed from the first direction. a partition wall disposed between the gas discharge valves and partitioning the gas discharge path into two or more in the second direction, wherein the gas discharge path forming member extends from the inside of the gas discharge path forming member to the outside. It has an exhaust for exhausting the gas.

According to this configuration, the gas discharge path forming member is arranged so as to collectively cover the gas discharge valves of the two adjacent power storage elements, and the gas discharge path inside the gas discharge path forming member is When viewed from the first direction, the two storage elements are partitioned by the partition wall. Therefore, the common gas discharge path forming member can relatively easily form the gas discharge paths of the two adjacent storage elements, and the pressure of the gas discharged from one of the gas discharge valves of the two adjacent storage elements can be reduced. can prevent the other gas discharge valve from opening (valve opening). Furthermore, since the gas discharge path forming member has the discharge portion, the gas discharged from the electric storage element and flowed into the gas discharge path can be discharged to the outside of the gas discharge path forming member through the discharge portion. As a result, the gas can be discharged to the outside of the gas discharge passage forming member while the temperature and speed of the gas are lowered. Thus, according to the power storage device according to this aspect, safety can be improved with a relatively simple configuration.

The gas discharge path forming member is connected to a first wall portion forming an inner surface of the gas discharge path facing the plurality of power storage elements in the first direction, and to the first wall portion to form the gas discharge path. and a second wall portion forming an inner surface facing a third direction intersecting the first direction and the second direction, and the discharge portion is provided on the second wall portion. good.

According to this configuration, the discharge portion, which is the outlet of the gas from the gas discharge passage, is provided in the second wall portion of the gas discharge passage forming member, which is not located in front of the gas discharge valve. Therefore, before the gas discharged from the gas discharge valve is discharged from the discharge portion, the gas can more reliably collide with the inner surface (first wall portion) of the gas discharge path forming member. This allows the temperature and velocity of the gas to be lowered more reliably.

The discharge portion may be a notch-shaped opening formed in the first direction from an end portion of the second wall portion that is close to the plurality of power storage elements in the first direction.

According to this configuration, the discharge portion is provided in a cutout shape from the end edge of the second wall portion, which is the side wall portion of the gas discharge path forming member. Therefore, it is possible to form the entire shape of the gas discharge path forming member by press working, casting, or the like, and at the same time, form the opening portion, which is the discharge portion. This makes it possible to easily form a gas discharge passage having a discharge portion.

A first spacer having the partition wall portion is arranged between the two storage elements, the first spacer having a spacer main body positioned between the two storage elements, and the partition wall The portion may be provided so as to protrude from the spacer main body into the gas discharge passage.

According to this configuration, the partition wall portion is provided as part of the first spacer arranged between the two adjacent power storage elements. Therefore, by combining the first spacer and the gas discharge path forming member, it is possible to easily form the gas discharge path having the partition wall.

The power storage device may further include a second spacer disposed along the first spacer between the two power storage elements and having electrical insulation.

According to this configuration, the electrical insulation between the containers of two adjacent storage elements can be entrusted to the second spacer. Therefore, the first spacer having the partition wall can be made of a material having higher heat resistance than resin, such as metal or carbon fiber. This reduces the possibility that the partition wall will be damaged by the heat of the gas, and as a result, the effect of partitioning the gas discharge path by the partition wall can be exhibited more reliably.

Hereinafter, power storage devices according to embodiments of the present invention (including modifications thereof) will be described with reference to the drawings. All of the embodiments described below are generic or specific examples. Numerical values, shapes, materials, constituent elements, arrangement positions and connection forms of constituent elements, manufacturing processes, order of manufacturing processes, and the like shown in the following embodiments are examples, and are not intended to limit the present invention. In each drawing, dimensions and the like are not strictly illustrated. Furthermore, in each figure, the same reference numerals are given to the same or similar components. In addition, the name of each component (each component) of this embodiment is the name in this embodiment, and may be different from the name of each component (each component) in the background art.

In the following description and drawings, the lateral direction of the exterior body of the power storage device or the opposing direction of the short sides of the power storage element is defined as the Y-axis direction. The longitudinal direction of the exterior body of the power storage device or the alignment direction of the plurality of power storage elements is defined as the X-axis direction. The direction in which the main body of the exterior body and the lid body of the power storage device are aligned, or the vertical direction, is defined as the Z-axis direction. These X-axis direction, Y-axis direction, and Z-axis direction are directions that cross each other (perpendicularly in this embodiment). Depending on the mode of use, the Z-axis direction may not be the vertical direction, but for convenience of explanation, the Z-axis direction will be described below as the vertical direction.

In the following description, for example, the positive direction of the X-axis indicates the arrow direction of the X-axis, and the negative direction of the X-axis indicates the direction opposite to the positive direction of the X-axis. The same applies to the Y-axis direction and the Z-axis direction. When simply referred to as the "X-axis direction", it means either or both directions parallel to the X-axis. The same applies to terms relating to the Y-axis and Z-axis.

Furthermore, expressions indicating relative directions or orientations such as parallel and orthogonal include cases where they are not strictly the directions or orientations. For example, two directions are orthogonal to each other means not only that the two directions are completely orthogonal, but also that they are substantially orthogonal, that is, the difference is about several percent. It also means to contain. In the following description, the expression "insulation" means "electrical insulation".

(Embodiment)
[1. General description of power storage device]
First, a schematic configuration of a power storage device 1 according to an embodiment will be described. FIG. 1 is a perspective view showing the appearance of a power storage device 1 according to an embodiment. FIG. 2 is an exploded perspective view of the power storage device 1 according to the embodiment. FIG. 3 is a perspective view showing the appearance of the storage device 100 according to the embodiment. Inside the exterior body 10, in addition to the members shown in FIG. 2 and subsequent drawings, electrical devices such as relays and control devices, and wiring connected to the electrical devices are accommodated. Illustrations and descriptions are omitted as appropriate.

The power storage device 1 is a device that can charge electricity from the outside and discharge electricity to the outside, and has a substantially rectangular parallelepiped shape in the present embodiment. The power storage device 1 is, for example, a battery module (assembled battery) used for power storage or power supply. Specifically, the power storage device 1 is, for example, an automobile, a motorcycle, a watercraft, a ship, a snowmobile, an agricultural machine, a construction machine, or a rolling stock for an electric railway. It is used as a battery etc. Examples of the vehicles include electric vehicles (EV), hybrid electric vehicles (HEV), plug-in hybrid electric vehicles (PHEV), and fossil fuel (gasoline, light oil, liquefied natural gas, etc.) vehicles. Examples of railway vehicles for the electric railway include electric trains, monorails, linear motor cars, and hybrid trains having both diesel engines and electric motors. The power storage device 1 can also be used as a stationary battery or the like for home or business use.

As shown in FIGS. 1 and 2 , the power storage device 1 includes an exterior body 10 and power storage element units 20 housed in the exterior body 10 . A busbar holder 30 that holds a busbar 60 joined to the storage element 100 is arranged above the storage element unit 20 . The exterior body 10 is a box-shaped (substantially rectangular parallelepiped) container (module case) that constitutes the housing of the power storage device 1 . The exterior body 10 is arranged outside the power storage element unit 20 and the busbar holder 30, fixes them at predetermined positions, and protects them from impacts and the like. The exterior body 10 is made of, for example, polycarbonate (PC), polypropylene (PP), polyethylene (PE), polystyrene (PS), polyphenylene sulfide resin (PPS), polyphenylene ether (PPE (including modified PPE)), polyethylene terephthalate ( PET), polybutylene terephthalate (PBT), polyetheretherketone (PEEK), tetrafluoroethylene-perfluoroalkyl vinyl ether (PFA), polytetrafluoroethylene (PTFE), polyethersulfone (PES), polyamide (PA) , ABS resin, or an insulating member such as a composite material thereof, or a metal coated with an insulating coating.

The exterior body 10 has an exterior body main body 12 and a lid body 11 . The exterior body main body 12 is a bottomed rectangular cylindrical housing with an opening 12a formed at the end in the positive direction of the Z axis, and accommodates the electric storage element unit 20 and the like. The lid 11 is a rectangular member that closes the opening 12 a of the exterior main body 12 . The lid body 11 is joined to the exterior body main body 12 by an adhesive, heat sealing, ultrasonic welding, laser welding, or the like.

A pair of external terminals 19 , which are a pair of positive and negative module terminals, are arranged on the lid 11 . The power storage device 1 charges electricity from the outside and discharges electricity to the outside through the pair of external terminals 19 . The external terminal 19 is made of a conductive member made of metal such as aluminum, aluminum alloy, copper, or copper alloy. The lid 11 is further provided with an exhaust pipe 15 for guiding the gas generated inside the exterior 10 to the outside of the exterior 10 . For example, when one storage element 100 opens and gas is discharged, the storage device 1 is designed to send the gas from the inside of the exterior body 10 to the outside through the exhaust pipe 15 . More specifically, in the present embodiment, the gas discharged from the power storage elements 100 is discharged outside from the inside of the gas discharge path forming member 250 arranged along the plurality of power storage elements 100, and then discharged to the outside through the exhaust pipe. 15 to the outside of the exterior body 10 . When the power storage device 1 is mounted in an automobile or the like, a gas hose (not shown), for example, is connected to the exhaust pipe 15 . As a result, the gas discharged from the power storage element 100 is guided to a predetermined position without affecting other members around the power storage element 100 and the human body.

The storage element unit 20 has a storage element array 101 including a plurality of storage elements 100 and a restraining member 200 that restrains the storage element array 101 . Electric storage element array 101 includes a plurality of electric storage elements 100 and cell holders 130 arranged along each of the plurality of electric storage elements 100 . In the present embodiment, storage element array 101 has eight storage elements 100 and eight cell holders 130 .

The storage element 100 is a secondary battery (single battery) capable of charging and discharging electricity. In this embodiment, the storage element 100 is a non-aqueous electrolyte secondary battery such as a lithium ion secondary battery. As shown in FIG. 3 , the storage element 100 has a flat rectangular parallelepiped (square) container 110 and a pair of (positive and negative electrode) electrode terminals 120 fixed to the container 110 . Inside the container 110, an electrode assembly, a current collector, an electrolytic solution, and the like (not shown) are accommodated. An example of the electrode body of the storage element 100 is a wound electrode body formed by winding a positive electrode plate and a negative electrode plate with a separator sandwiched between them in layers. In addition, the storage element 100 may be provided with a laminated (stacked) electrode body formed by stacking a plurality of flat plate-shaped electrode plates, or a bellows-shaped electrode body formed by folding the electrode plates into a bellows shape. good.

The storage element 100 is not limited to a non-aqueous electrolyte secondary battery, and may be a secondary battery other than a non-aqueous electrolyte secondary battery, or may be a capacitor. The power storage device 100 may be a primary battery that can use stored electricity without being charged by the user, instead of a secondary battery. The storage element 100 may be a battery using a solid electrolyte. The storage element 100 may be a pouch-type storage element. Moreover, the shape of the electric storage element 100 is not limited to the rectangular shape described above, and may be other shapes such as a polygonal columnar shape, a cylindrical shape, an elliptical columnar shape, and an oval columnar shape.

In this embodiment, as shown in FIG. 3, the container 110 has a pair of long side surfaces 110a, a pair of short side surfaces 110b, and a terminal arrangement surface 110c. The terminal arrangement surface 110c is a surface on which the positive and negative electrode terminals 120 are arranged. In this embodiment, a gas exhaust valve 105 is further arranged on the terminal arrangement surface 110c. When the internal pressure of the container 110 rises excessively, the gas discharge valve 105 is a part that receives the internal pressure and opens (opens the valve), thereby discharging the gas inside the container 110 to the outside. In the electric storage element array 101, each of the plurality of electric storage elements 100 is arranged in a posture in which the gas discharge valve 105 is oriented in the positive Z-axis direction and the long side surface 110a is oriented in the alignment direction (X-axis direction). there is In the present embodiment, the Z-axis plus direction is an example of a first direction, and the X-axis direction is an example of a second direction that intersects with the first direction.

The electric storage element row 101 configured in this way is restrained by the restraining member 200 in the direction in which the plurality of electric storage elements 100 are arranged (the X-axis direction). The binding member 200 includes a pair of end members 210 arranged on both sides of the storage element array 101 in the X-axis direction, a pair of side members 220 arranged on both sides of the storage element array 101 in the Y-axis direction, and a storage element array. 101 and a gas discharge path forming member 250 arranged in the positive direction of the Z axis. In the present embodiment, the gas discharge path forming member 250 serves to connect the pair of end members 210 in the X-axis direction, and also serves to form a discharge path for the gas discharged from the power storage element 100. . The configuration of the gas discharge path forming member 250 and its surroundings will be described later with reference to FIGS. 4 to 7. FIG.

The busbar holder 30 is a flat rectangular insulating member arranged to face the terminal arrangement surface 110c of the power storage element 100 and holds a plurality of busbars 60 and electrical equipment (not shown). The busbar holder 30 may be made of any electrically insulating resin material or the like that can be used for the exterior body 10 described above. The busbar holder 30 is in contact with the terminal arrangement surface 110c of the plurality of power storage elements 100 and fixed to the exterior body 10, thereby restricting the upward movement (Z-axis positive direction) of the plurality of power storage elements 100. It may function as a regulating member. The busbar 60 arranged in the busbar holder 30 is positioned with respect to the electrode terminal 120 to be joined, and in this state is joined to the electrode terminal 120 by laser welding or the like. In the present embodiment, among eight power storage elements 100 included in power storage element unit 20 , two adjacent power storage elements 100 are connected in parallel by bus bar 60 . As a result, four sets of power storage elements 100 connected in parallel are formed. Furthermore, four sets of power storage elements 100 are connected in series by three bus bars 60 . The form of electrical connection of the eight power storage elements 100 by the busbars 60 is not limited to this. For example, all the eight power storage elements 100 may be connected in series by a plurality of busbars 60 . Further, the number of storage elements 100 included in the storage element unit 20 is not limited to eight. The number of storage elements 100 included in the storage element unit 20 may be two or more.

In power storage device 1 configured as described above, gas discharge path forming member 250 disposed as a part of restraining member 200 has a plurality of partitioned gas discharge paths therein. The configuration of the gas discharge path forming member 250 and its surroundings will be described in detail below with reference to FIGS. 4 to 7. FIG.

[2. Concerning the configuration of the gas discharge path forming member and its periphery]
FIG. 4 is an exploded perspective view of the storage element unit 20 according to the embodiment. FIG. 5 is an exploded perspective view of the storage element array 101 according to the embodiment. FIG. 6A is a perspective cross-sectional view of the gas discharge path forming member 250 according to the embodiment. In FIG. 6A, the gas exhaust path forming member 250 is shown cut along line VI-VI in FIG. FIG. 6B is a schematic diagram showing the position of the partition wall portion 155 inside the gas discharge path forming member 250 according to the embodiment. FIG. 7 is a perspective cross-sectional view showing the structural relationship between the gas discharge path forming member 250 and the partition wall portion 155 according to the embodiment. The position of the cross section in FIG. 7 corresponds to the position of the cross section in FIG. 6A.

As shown in FIGS. 4 and 5, in the storage element unit 20, cell holders 130 are arranged on both sides of a set of storage elements 100 composed of two storage elements 100 adjacent to each other. In the present embodiment, four groups of energy storage elements 100 each including a pair of cell holders 130 and two energy storage elements 100 sandwiched between the pair of cell holders 130 are arranged in the X-axis direction. The cell holder 130 is an example of a second spacer, and is made of resin such as PC, PP, PE, and PS, which are exemplified as materials of the exterior body 10 described above.

In the present embodiment, two power storage elements 100 sandwiched between a pair of cell holders 130 are connected in parallel by bus bars 60 . Therefore, even if the container 110 of the two storage elements 100 is a conductive member such as a metal and the cell holder 130 having electrical insulation is not arranged between the two storage elements 100, the A problem such as a short circuit is less likely to occur between the two storage elements 100 .

In the electric storage element row 101, at a position where two cell holders 130 are arranged in a row, an inter-cell plate 150 is arranged sandwiched between the two cell holders 130, as shown in FIG. Inter-cell plate 150 is an example of a first spacer, and is made of metal such as iron or an aluminum alloy in the present embodiment. In the present embodiment, inter-cell plate 150 functions as a spacer that fills the space between two power storage elements 100 located on both sides of inter-cell plate 150 . In the present embodiment, the storage element row 101 has three positions in which two cell holders 130 are continuously arranged in the X-axis direction. there is

In this manner, the storage element row 101 having the plurality of storage elements 100, the plurality of cell holders 130, and the plurality of inter-cell plates 150 is bound by the binding member 200 as described above. Specifically, as shown in FIG. 4 , a pair of end members 210 facing each other in the X-axis direction are connected by a pair of side members 220 and a gas discharge path forming member 250 . can be constrained in the X-axis direction. In this embodiment, the end of the side member 220 in the X-axis direction is joined to the end of the end member 210 in the Y-axis direction by two bolts 290 . Specifically, two bolts 290 arranged through the end of the side member 220 in the X-axis direction are screwed into two nuts 211 provided at the end of the end member 210 in the Y-axis direction. . The X-axis direction end of the gas discharge path forming member 250 is joined to the Z-axis plus direction end of the end member 210 by one bolt 290 . Specifically, one bolt 290 disposed through the end of the gas discharge path forming member 250 in the X-axis direction is attached to the nut portion 212 provided at the end of the end member 210 in the positive Z-axis direction. Screwed. With such a configuration, the pair of end members 210 facing each other in the X-axis direction can firmly restrain the storage element array 101 sandwiched between the pair of end members 210 in the X-axis direction.

In this embodiment, the restraining member 200 is made of metal such as iron or an aluminum alloy. A surface of the storage element array 101 facing the end member 210 is formed by a cell holder 130 arranged at an end portion of the storage element array 101 . Therefore, the electric storage element row 101 and the end member 210 are insulated by the cell holder 130 at the end. The cell holder 130 has a wall facing the short side 110 b of the container 110 and located between the short side 110 b and the side member 220 . Therefore, the electric storage element row 101 and the side member 220 are insulated by the plurality of cell holders 130 .

In the present embodiment, as shown in FIGS. 4 and 5, the gas discharge path forming member 250 is positioned on the side of the power storage element 100 in the positive direction of the Z axis. Specifically, in the electric storage element array 101, the gas discharge path forming member 250 is arranged so as to collectively cover the plurality of gas discharge valves 105 directed in the positive Z-axis direction and arranged in the X-axis direction. there is As shown in FIG. 6A, the gas discharge path forming member 250 has a first wall portion 251 and second wall portions 252 connected to both ends of the first wall portion 251 in the Y-axis direction. That is, in the gas discharge path forming member 250 , the gas discharge path 254 is formed by the space surrounded by the first wall portion 251 and the pair of second wall portions 252 . In the present embodiment, as shown in FIG. 6B, the gas discharge passage 254 is partitioned into a plurality of partition walls 155 in the X-axis direction. Specifically, as shown in FIGS. 5 and 7 , partition wall portion 155 is arranged in power storage device 1 as part of inter-cell plate 150 . The inter-cell plate 150 has a plate body 151 positioned between two power storage elements 100 and a partition wall portion 155 protruding from the plate body 151 in the positive Z-axis direction. The plate body 151 is an example of a spacer body that the first spacer has. When the gas discharge path forming member 250 is arranged with respect to the electric storage element array 101, as shown in FIG. 7, the partition wall portion 155 is inserted inside the gas discharge path 254 (see FIGS. 6A and 6B). . As a result, the gas discharge path 254 is partitioned by the partition wall portion 155 between the two energy storage elements 100 facing each other with the inter-cell plate 150 interposed therebetween.

For example, when focusing on the center inter-cell plate 150 of the three inter-cell plates 150, the storage element 100 (denoted as storage element 100A in FIG. 5) is arranged on the side of the inter-cell plate 150 in the positive direction of the X axis. be done. A power storage element 100 (denoted as power storage element 100B in FIG. 5) is also arranged on the side of inter-cell plate 150 in the negative direction of the X axis. Thus, the partition wall portion 155 of the inter-cell plate 150 located between the storage elements 100A and 100B is located between the gas discharge valve 105 of the storage element 100A and the gas discharge valve 105 of the storage element 100B. and divides the gas discharge path 254 into two at this position. Three inter-cell plates 150 having such partition walls 155 are provided in the storage element array 101 in the present embodiment. As a result, as shown in FIG. 6B, one gas discharge passage 254 formed by the entire gas discharge passage forming member 250 is composed of four gas discharge passages 254 (gas discharge passages 254a, 254b, 254c in FIG. 6B, and 254d).

In this embodiment, the second wall portion 252 of the gas discharge path forming member 250 is provided with the discharge portion 255 . When the gas is discharged from the gas discharge valve 105 , the gas flows into the gas discharge passage 254 and is discharged from the discharge portion 255 to the outside of the gas discharge passage forming member 250 . More specifically, a discharge portion 255 is provided in each of gas discharge paths 254 a to 254 d formed by dividing the gas discharge path 254 by three partition walls 155 . 5 to 6A, four discharge portions 255 are formed on the second wall portion 252 of the gas discharge path forming member 250 in the negative direction of the Y axis. , four discharges 255 may be formed. One or more discharge portions 255 may be formed on both of the pair of second wall portions 252 facing each other in the Y-axis direction.

For example, when the gas discharge valve 105 of the power storage element 100A in FIG. 5 is opened, the gas discharged from the power storage element 100A flows into the gas discharge path 254c in FIG. 6B. The inflowing gas is discharged to the outside of the gas discharge path forming member 250 from the discharge portion 255 facing the gas discharge path 254c. After that, the gas is discharged to the outside of the exterior body 10 through an exhaust pipe 15 provided in the exterior body 10 .

As described above, power storage device 1 according to the present embodiment includes a plurality of power storage elements 100 , gas discharge path forming member 250 forming gas discharge path 254 , and partition wall portion 155 . Each of the plurality of power storage elements 100 has a gas discharge valve 105 facing in the positive Z-axis direction, which is the first direction, and arranged in the X-axis direction intersecting the positive Z-axis direction. The gas discharge path forming member 250 is arranged to face the plurality of gas discharge valves 105 in the positive Z-axis direction. The partition wall portion 155 is arranged between the gas discharge valves 105 of two adjacent power storage elements 100 among the plurality of power storage elements 100 when viewed from the Z-axis positive direction, and separates the gas discharge path 254 in the X-axis direction. Divide into 2 or more pieces. The gas discharge path forming member 250 has a discharge portion 255 for discharging gas from the inside of the gas discharge path forming member 250 to the outside.

As described above, when focusing on two adjacent power storage elements 100 (for example, the power storage elements 100A and 100B in FIG. 5), the gas discharge path forming member 250 according to the present embodiment can It is arranged so as to collectively cover the discharge valve 105 . Furthermore, the gas discharge path 254 inside the gas discharge path forming member 250 is defined by the partition wall 155 between the power storage elements 100A and 100B when viewed from the Z-axis plus direction (hereinafter referred to as “plan view”). partitioned. Therefore, the pressure of the gas discharged from the gas discharge valve 105 of one of the storage elements 100A and 100B is less likely to act on the gas discharge valve 105 of the other of the storage elements 100A and 100B. This reduces the possibility that the other gas exhaust valve 105 is opened (opened). That is, the possibility that two adjacent storage elements 100 open continuously is reduced. Furthermore, since the gas discharge path forming member 250 has the discharge portion 255 , the gas discharged from the power storage element 100 and flowed into the gas discharge path 254 flows out of the gas discharge path forming member 250 through the discharge portion 255 . can be made As a result, the gas can be discharged to the outside of the gas discharge path forming member 250 while the temperature and speed of the gas are lowered. Therefore, the gas can be safely guided to a specified position, for example, through the exhaust pipe 15 provided in the exterior body 10 . As a result, problems such as damage to the exterior body 10 that tend to occur when gas is discharged from two or more power storage elements 100 are suppressed. Thus, according to the power storage device 1 according to the present embodiment, safety can be improved with a simple configuration.

In this embodiment, the gas discharge path forming member 250 has a first wall portion 251 and a second wall portion 252 . The first wall portion 251 forms an inner surface of the gas discharge path 254 that faces the plurality of power storage elements 100 in the positive Z-axis direction. The second wall portion 252 is connected to the first wall portion 251 and forms an inner surface of the gas discharge passage 254 facing the Y-axis direction that intersects the positive Z-axis direction and the X-axis direction. The discharge portion 255 is provided on the second wall portion 252 .

Thus, the discharge portion 255 , which is the outlet of the gas from the gas discharge passage 254 , is provided on the second wall portion 252 of the gas discharge passage forming member 250 that is not positioned in front of the gas discharge valve 105 . Therefore, the gas discharged from the gas discharge valve 105 can more reliably collide with the inner surface (first wall portion 251 ) of the gas discharge path forming member 250 . This allows the temperature and velocity of the gas to be lowered more reliably.

As shown in FIGS. 4 to 6B, the discharge portion 255 according to the present embodiment is formed in a notch shape from the end portion of the second wall portion 252 near the plurality of power storage elements 100 toward the positive direction of the Z axis. It is an opening that has been

Thus, in the present embodiment, the discharge portion 255 is provided in a cutout shape from the edge of the second wall portion 252 which is the side wall portion of the gas discharge path forming member 250 . Therefore, it is possible to form the opening portion, which is the discharge portion 255, at the same time as forming the overall shape of the gas discharge path forming member 250 by press working, casting, or the like. In other words, operations such as drilling for the second wall portion 252 are unnecessary.

In the present embodiment, the partition wall portion 155 is realized by part of a member separate from the gas discharge path forming member 250 . Specifically, an inter-cell plate 150 having a partition wall portion 155 is arranged between two power storage elements 100 . Inter-cell plate 150 has a plate body 151 positioned between two storage elements 100 . The partition wall portion 155 is provided so as to protrude from the plate body 151 into the gas discharge passage 254 .

Thus, the partition wall portion 155 according to the present embodiment is a part of the inter-cell plate 150 that regulates the position of the two adjacent storage elements 100 or suppresses the expansion of each of the two storage elements 100. is provided as Therefore, by arranging the gas discharge path forming member 250 with respect to the storage element row 101 including the inter-cell plate 150, the arrangement of the partition wall portion 155 that partitions the gas discharge path 254 is completed. Therefore, work such as welding a member that is separate from the inter-cell plate 150 and that functions as the partition wall portion 155 to the gas discharge path forming member 250 is unnecessary.

In the present embodiment, a cell holder 130 is further arranged at a position where the inter-cell plate 150 is arranged in the electric storage element row 101 . That is, the power storage device 1 includes the cell holder 130 that is arranged along the inter-cell plate 150 between the two power storage elements 100 and has electrical insulation.

According to this configuration, the insulation between the containers 110 of two adjacent storage elements 100 can be entrusted to the cell holder 130 . Therefore, inter-cell plate 150 having partition walls 155 can be made of a material having higher heat resistance than resin, such as metal or carbon fiber. In this embodiment, inter-cell plate 150 is made of metal such as iron or an aluminum alloy. This reduces the possibility that the partition wall portion 155 will be damaged by the heat of the gas, and as a result, the effect of partitioning the gas discharge path 254 by the partition wall portion 155 can be exhibited more reliably.

[3. Modification]
Although the power storage device 1 according to the embodiment of the present invention has been described above, the present invention is not limited to this embodiment. In other words, the embodiments disclosed this time are illustrative in all respects and are not restrictive, and the scope of the present invention includes all changes within the meaning and range equivalent to the claims. included.

For example, the partition wall portion 155 does not need to be part of a member separate from the gas discharge path forming member 250, such as the inter-cell plate 150. The partition wall portion 155 may be a member that is fixed to the gas discharge path forming member 250 and has the sole purpose of partitioning the gas discharge path 254 . In this case, the partition wall portion 155 may be a member provided integrally with the gas discharge path forming member 250 (part of the gas discharge path forming member 250). The partition wall portion 155 may be a member separate from the gas discharge path forming member 250, and may be a member joined to the gas discharge path forming member 250 by welding, adhesion, or the like. In either case, the partition wall portion 155 is positioned between the two gas discharge valves 105 in plan view, so that the pressure of the gas discharged from one gas discharge valve 105 is The effect of making it difficult to act on 105 is exhibited.

The number of partition wall portions 155 arranged with respect to the gas discharge path forming member 250 is not limited to three, and may be two or less, or may be four or more. When the number included in the storage element array 101 is eight, as in the above embodiment, so that one partition wall portion 155 always exists between two gas discharge valves 105 adjacent to each other in a plan view, Seven partition walls 155 may be arranged. Alternatively, one partition wall portion 155 may be arranged only between the two central gas discharge valves 105 in the X-axis direction among the eight gas discharge valves 105 arranged in the X-axis direction. In either case, when focusing on one partition wall portion 155 , at least two gas discharge passages 254 partitioned by the partition wall portion 155 exist inside the gas discharge passage forming member 250 . Therefore, the effect that the gas pressure of one of the two gas exhaust valves 105 located on both sides of the partition wall portion 155 in plan view is less likely to act on the other gas exhaust valve 105 is exhibited.

When one partition wall portion 155 is arranged in the gas discharge passage forming member 250, the number of gas discharge passages 254 partitioned by the partition wall portion 155 may be three or more. For example, it is assumed that the first wall portion 251 of the gas discharge path forming member 250 has a wall portion projecting in the negative Z-axis direction and elongated in the X-axis direction at the center portion in the Y-axis direction. In this case, the partition wall portion 155 that is parallel to the ZY plane and intersects the long wall portion in the X-axis direction is arranged in the gas discharge passage forming member 250, thereby forming the gas discharge passage. Four partitioned gas discharge paths 254 may be formed inside the member 250 .

The first spacer need not be the inter-cell plate 150 if the partition wall 155 is arranged as part of the first spacer. The first spacer having the partition wall portion 155 may be a member having a size and shape that fills at least part of the space existing between the two power storage elements 100 arranged in the X-axis direction. For example, the cell holder 130 may be provided in the power storage device 1 as a first spacer having the partition wall portion 155 . In this case, it is preferable that the cell holder 130 be made of resin having high heat resistance. Furthermore, when cell holder 130 is provided in power storage device 1 as a first spacer, inter-cell plate 150 may be a second spacer arranged along the first spacer. The second spacer does not necessarily have a shape that holds the storage element 100 like the cell holder 130 does. The second spacer arranged along the inter-cell plate 150, which is the first spacer, may be a simple flat plate member made of an insulating material.

The discharge portion 255 of the gas discharge path forming member 250 does not need to be an opening provided in a cutout shape from the edge of the second wall portion 252 . The discharge portion 255 may be a through hole penetrating the second wall portion 252 in the thickness direction (Y-axis direction). Like the gas discharge valve 105 in the power storage element 100, the discharge part 255 is normally in a closed state, and when the internal pressure rises, the discharge part 255 is broken, destroyed, or fused to open the opening (through hole). It may be a portion to be formed (for example, a thin portion). In other words, the discharge portion 255 may be a portion that can discharge gas discharged from the power storage element 100 to the outside of the gas discharge path forming member 250 through the gas discharge path 254 . The discharge portion 255 is a portion that is closed when gas is not discharged from the power storage element 100 (for example, an opening closed with a sheet-like member or an opening sealed with an elastic member). may

The position where the discharge portion 255 is provided in the gas discharge path forming member 250 does not have to be the second wall portion 252 . A discharge portion 255 may be arranged on the first wall portion 251 . In this case, it is preferable that the discharge portion 255 is arranged in a region of the first wall portion 251 that does not face the gas discharge valve 105 . As a result, even when the discharge portion 255 is disposed on the first wall portion 251, the gas discharged from the gas discharge valve 105 is caused to once collide with the inner surface of the first wall portion 251, and then the discharge portion 255 can be discharged to the outside of the gas discharge path forming member 250. Therefore, the gas can be discharged to the outside of the gas discharge path forming member 250 in a state where the pressure and temperature of the gas are lowered from the time when the gas is discharged from the gas discharge valve 105 .

Gas exhaust path forming member 250 need not be part of restraining member 200 . The gas discharge path forming member 250 may be a member that is arranged to face the plurality of gas discharge valves 105 and that does not connect the pair of end members 210 . In this case, the gas discharge path forming member 250 may be, for example, a part of the busbar holder 30 or a member fixed to the busbar holder 30 and separate from the busbar holder 30 .

Moreover, the form constructed by arbitrarily combining the constituent elements included in the above embodiment and its modifications is also included in the scope of the present invention.

INDUSTRIAL APPLICABILITY The present invention can be applied to a power storage device having a power storage element such as a lithium ion secondary battery.

Reference Signs List 1 power storage device 100, 100A, 100B power storage element 101 power storage element array 105 gas exhaust valve 130 cell holder 150 inter-cell plate 151 plate body 155 partition wall portion 200 restraining member 210 end member 220 side member 250 gas exhaust path forming member 251 first wall Part 252 Second wall part 254, 254a, 254b, 254c, 254d Gas discharge path 255 Discharge part

Claims (5)

a plurality of power storage elements each having a gas discharge valve facing the first direction and arranged in a second direction intersecting the first direction;
a gas discharge path forming member that forms a gas discharge path and is disposed facing the plurality of gas discharge valves in the first direction;
A partition wall disposed between the gas discharge valves of two adjacent power storage elements among the plurality of power storage elements when viewed from the first direction, and partitioning the gas discharge path into two or more in the second direction. and
The gas discharge path forming member has a discharge portion for discharging gas from the inside of the gas discharge path forming member to the outside.
storage device. The gas discharge path forming member is connected to a first wall portion forming an inner surface of the gas discharge path facing the plurality of power storage elements in the first direction, and to the first wall portion to form the gas discharge path. and a second wall forming an inner surface facing a third direction intersecting the first direction and the second direction,
The discharge part is provided on the second wall part,
The power storage device according to claim 1 . The discharge portion is an opening formed in a notch shape in the first direction from an end portion of the second wall portion that is close to the plurality of power storage elements in the first direction.
The power storage device according to claim 2 . A first spacer having the partition wall is arranged between the two storage elements,
The first spacer has a spacer body positioned between the two power storage elements,
The partition wall portion is provided so as to protrude from the spacer body into the gas discharge passage,
The power storage device according to any one of claims 1 to 3. further comprising a second spacer disposed along the first spacer between the two storage elements and having electrical insulation;
The power storage device according to claim 4.

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