JP2024021469A - Power storage device - Google Patents

Abstract

An object of the present invention is to provide a power storage device with a simple configuration and improved safety. A power storage device 1 includes a power storage element 100, an exhaust duct 350, and an insulating member 320 disposed between the exhaust duct 350 and the power storage element 100. The power storage element 100 is arranged with the gas exhaust valve 131 facing in the positive direction of the Z-axis. The exhaust duct 350 has a metal facing surface portion 361 in which a through hole 362 is formed at a position facing the gas exhaust valve 131 . The insulating member 320 has an insulating main body portion 321 and a first cylindrical portion 323. Insulating main body portion 321 is located between opposing surface portion 361 of exhaust duct 350 and power storage element 100. An opening 322 is formed in the insulating main body 321 at a position between the gas exhaust valve 131 and the through hole 362. The first cylindrical portion 323 forms a space communicating with the opening 322, penetrates through the through hole 362 of the exhaust duct 350, and projects into the interior of the exhaust duct 350. [Selection diagram] Figure 7

Description

The present invention relates to a power storage device including a power storage element.

Conventionally, in a power storage device including a power storage element, a duct (exhaust duct) for guiding gas discharged from the power storage element to the outside of the power storage device is sometimes arranged. For example, Patent Document 1 discloses a power supply device having a plurality of battery cells and a gas duct. The gas duct is a hollow prismatic member extending in the stacking direction of the battery cells. A connecting opening is provided on the bottom side of the gas duct at a position corresponding to the gas exhaust valve of each battery cell. Each of the connecting openings is configured to communicate with the gas exhaust port when the gas exhaust valve is opened, and high-pressure gas discharged from the battery cell is guided into the gas duct.

Patent No. 6151254

In the conventional power supply device (power storage device) described above, the gas duct (exhaust duct) is made of resin, which has the advantage of excellent workability and fewer design restrictions. However, in the case of an exhaust duct made of resin, problems such as damage (such as melting or deformation) due to heat are likely to occur when, for example, a gas exhaust valve of a battery cell (power storage element) is opened. If the exhaust duct is damaged, gas will leak out from an unexpected location, which will cause adverse effects to spread when gas is exhausted from the power storage element. In particular, in recent years, the capacity of power storage elements has increased, and as a result, problems due to the heat of the power storage elements when the valve is opened are becoming more likely to occur. Therefore, for example, it is conceivable to arrange a member such as a metal member, which has higher heat resistance than a resin member, in the exhaust duct. However, in this case, problems arise, such as an increase in the number of parts or an increase in manufacturing costs. Furthermore, when a metal member is placed near the power storage element, there arises the problem of how to electrically insulate it from the power storage element.

The present invention was made by the inventors of the present application newly paying attention to the above-mentioned problem, and an object of the present invention is to provide a power storage device with a simple configuration and improved safety.

A power storage device according to one aspect of the present invention includes a power storage element arranged with a gas exhaust valve capable of discharging internal gas facing in a first direction, and a power storage element arranged on the first direction side of the power storage element. , an exhaust duct forming a flow path for gas discharged from the gas exhaust valve, and an insulating member disposed between the exhaust duct and the power storage element, the exhaust duct being connected to the power storage element. A metal opposing surface portion forming opposing surfaces has a through hole formed at a position facing the gas exhaust valve, and the insulating member is configured to connect the opposing surface portion and the power storage element. an insulating main body portion located between the gas exhaust valve and the through hole, the insulating body portion having an opening formed at a position between the gas exhaust valve and the through hole, and a first cylindrical portion forming a space communicating with the opening portion, and a first cylindrical portion that penetrates the hole and projects into the interior of the exhaust duct.

According to the power storage device according to the present invention, safety can be improved with a simple configuration.

FIG. 1 is a perspective view showing the appearance of a power storage device according to an embodiment. FIG. 2 is a perspective view showing an end portion of a power storage device according to an embodiment where a gas discharge port is provided. 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 element according to an embodiment. FIG. 2 is a perspective view showing the positional relationship between an exhaust duct, an insulating member, and a plurality of power storage elements according to an embodiment. It is an enlarged perspective view showing a part of a first duct member and an insulating member according to an embodiment. FIG. 2 is a perspective cross-sectional view showing the configuration of an exhaust duct and its surroundings according to an embodiment.

(1) A power storage device according to one aspect of the present invention includes a power storage element arranged with a gas exhaust valve capable of discharging internal gas facing in a first direction, and a power storage element on the first direction side. an exhaust duct that is disposed in the gas exhaust valve and forms a flow path for gas discharged from the gas exhaust valve; and an insulating member that is disposed between the exhaust duct and the electricity storage element, and the exhaust duct includes A metal facing surface portion forming a surface facing the power storage element, the facing surface portion having a through hole formed at a position facing the gas exhaust valve, and the insulating member is connected to the facing surface portion and the power storage device. an insulating main body portion located between the gas discharge valve and the through hole and having an opening formed at a position between the gas exhaust valve and the through hole; and a first cylindrical portion forming a space communicating with the opening. , a first cylindrical portion that penetrates the through hole and projects into the interior of the exhaust duct.

According to this configuration, the first cylindrical portion protrudes to the inside of the exhaust duct, so that the gas discharged from the electricity storage element efficiently flows into the inside of the exhaust duct. Furthermore, since at least the facing surface portion of the exhaust duct is made of metal, there is a low possibility that melting or deformation due to heat will occur. Furthermore, although the metal facing surface portion is the part of the exhaust duct closest to the power storage element, electrical insulation from the power storage element is ensured by the insulating main body part. Furthermore, since the first cylindrical portion is formed to a size that protrudes into the inside of the exhaust duct, the creepage distance between the electricity storage element and the opposing surface portion through the opening of the insulating main body portion is also relatively long. . In this way, the power storage device according to this aspect is a power storage device with a simple configuration and improved safety.

(2) In the power storage device according to (1) above, the exhaust duct includes a metal first duct member including the opposing surface portion, and an upper wall portion that faces the opposing surface portion in the first direction. A second duct member made of metal may also be included.

According to this configuration, since the portion of the exhaust duct that faces the through hole is also made of metal, the possibility of damage to the exhaust duct when the power storage element is opened is further reduced. Furthermore, since the exhaust duct is manufactured by combining two members (the first duct member and the second duct member) arranged in the first direction, it is difficult to manufacture an exhaust duct that has a space inside that serves as a gas flow path. It's easy.

(3) In the power storage device according to (2) above, the first duct member extends from each of the opposing surface portion and both ends of the opposing surface portion in a second direction perpendicular to the first direction. and a side wall section standing upright toward the duct member, and the second duct member may be a flat member connected to the pair of side wall sections.

According to this configuration, for example, the first duct member can be manufactured by bending both ends of the sheet metal in the second direction, and the second duct member can be manufactured by cutting the sheet metal to a predetermined size. In other words, the exhaust duct can be manufactured through a relatively easy process.

(4) In the power storage device according to (3) above, the second duct member is a cover member disposed to cover the power storage element, the insulating member, and the first duct member from the first direction side. It may be a part of.

According to this configuration, a part of the cover member that covers the power storage element and the like forms a part of the exhaust duct, so that the power storage device can be made smaller, more space-saving, or lighter.

(5) In the power storage device according to any one of (1) to (4) above, the insulating member further includes a second insulating member that protrudes from the opening of the insulating main body toward the gas exhaust valve. The cylindrical portion may include a second cylindrical portion that forms a gas flow path that communicates with the first cylindrical portion.

According to this configuration, even if there is a gap between the gas exhaust valve and the insulating main body, the second cylindrical part receives the gas, so that the gas exhausted from the gas exhaust valve is efficiently transferred to the exhaust duct. You will be guided inside.

(6) In the power storage device according to any one of (1) to (5) above, a plurality of the power storage elements are arranged side by side, and the exhaust duct is arranged along the direction in which the plurality of power storage elements are arranged. It may be extended as follows.

According to this configuration, the gas is exhausted all at once from one end of the exhaust duct extending along the power storage element array, so that the gas can be easily processed.

Hereinafter, a power storage device according to an embodiment of the present invention (including variations thereof) will be described with reference to the drawings. The embodiments described below are all inclusive or specific examples. The numerical values, shapes, materials, components, arrangement positions and connection forms of the components, manufacturing steps, order of manufacturing steps, etc. shown in the following embodiments are merely examples, and do not limit the present invention. In each figure, dimensions etc. are not strictly illustrated. In each figure, the same or similar components are designated by the same reference numerals.

In the following description and drawings, the direction in which a pair of electrode terminals (positive electrode side and negative electrode side) in one power storage element are lined up, the opposing direction of the short sides of the container of the power storage element, or the short direction of the exterior body is referred to as Defined as axial direction. The direction in which the plurality of power storage elements are lined up, the direction in which the long sides of the container of the power storage elements face each other, or the longitudinal direction of the exterior body is defined as the Y-axis direction. The direction in which the power storage elements and bus bars are arranged, the direction in which the main body and lid of the container of the power storage element are arranged, the direction in which the main body and the lid of the exterior body are arranged, 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 intersect with each other (orthogonal 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 as the vertical direction below.

In the following description, the X-axis plus direction refers to the arrow direction of the X-axis, and the X-axis minus direction refers to the opposite direction to the X-axis plus direction. When simply referred to as the X-axis direction, it refers to both directions or either of the X-axis plus direction and the X-axis minus direction. The same applies to the Y-axis direction and the Z-axis direction. Below, the Z-axis plus direction may be referred to as a first direction, and the Y-axis direction may be referred to as a second direction. Expressions indicating relative directions or orientations, such as parallel and orthogonal, include cases where the directions or orientations are not strictly speaking. For example, two directions being parallel does not only mean that the two directions are completely parallel, but also that they are substantially parallel, that is, with a difference of, for example, a few percent. means. Furthermore, in the following description, when expressed as "insulation", it means "electrical insulation".

[1. General explanation of power storage device]
First, a general description of power storage device 1 in this embodiment will be given. FIG. 1 is a perspective view showing the appearance of a power storage device 1 according to an embodiment. FIG. 2 is a perspective view showing an end portion of the power storage device 1 according to the embodiment where a gas discharge port 358 is provided. FIG. 3 is an exploded perspective view of power storage device 1 according to the embodiment.

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 this embodiment. For example, the power storage device 1 is a battery module (battery assembly) used for power storage, power supply, or the like. Specifically, the power storage device 1 is used for driving or starting an engine of a moving object such as an automobile, a motorcycle, a watercraft, a ship, a snowmobile, an agricultural machine, a construction machine, or a railway vehicle for an electric railway. Used as batteries, etc. Examples of the above-mentioned vehicles include electric vehicles (EVs), hybrid electric vehicles (HEVs), plug-in hybrid electric vehicles (PHEVs), and fossil fuel (gasoline, diesel oil, liquefied natural gas, etc.) vehicles. Examples of the above-mentioned railway vehicles for electric railways include electric trains, monorails, linear motor cars, and hybrid electric trains equipped with both a diesel engine and an electric motor. The power storage device 1 can also be used as a stationary battery or the like used for home or business purposes.

As shown in FIG. 1, power storage device 1 includes a power storage unit 10 and a board unit 20 attached to power storage unit 10. The power storage unit 10 has a substantially rectangular parallelepiped shape that is elongated in the Y-axis direction. The board unit 20 is a device that can monitor the state of the power storage element 100 included in the power storage unit 10 and control the power storage element 100, and has a circuit board and the like inside. In the present embodiment, the substrate unit 20 is a flat rectangular member that is attached to the end of the power storage unit 10 in the longitudinal direction, that is, to the side surface of the power storage unit 10 on the Y-axis negative direction side.

As shown in FIG. 3, the power storage unit 10 includes a plurality of power storage elements 100, a plurality of spacers 200, an exterior body 300, a plurality of bus bars 400, a support body 500, and an exhaust duct 350. . The power storage unit 10 includes cables 410 and 420 (see FIG. 1), which are not shown in FIG.

The power storage element 100 is a secondary battery (single battery) that can charge and discharge electricity, and more specifically, is a non-aqueous electrolyte secondary battery such as a lithium ion secondary battery. The power storage element 100 has a flat rectangular parallelepiped shape (prismatic shape), and in this embodiment, 14 power storage elements 100 are arranged in a line in the Y-axis direction. The size and shape of power storage element 100, the number of power storage elements 100 arranged, etc. are not limited, and for example, only one power storage element 100 may be arranged. The power 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 a capacitor. The power storage element 100 may be not a secondary battery but a primary battery that allows the user to use the stored electricity without charging it. Power storage element 100 may be a battery using a solid electrolyte. The power storage element 100 may be a pouch type power storage element. A detailed description of the configuration of power storage element 100 according to this embodiment will be described later using FIG. 4.

Spacer 200 is a flat, rectangular member that is arranged in line with power storage element 100 in the Y-axis direction and heats and/or insulates power storage element 100 and other members. In the present embodiment, spacers 200 are arranged at both ends of a row of 100 power storage elements made up of a plurality of power storage elements 100 and between two adjacent power storage elements 100 in the 100 row of power storage elements. The spacer 200 is made of, for example, an insulating member such as any resin material that can be used for the exterior body 300 described below.

The exterior body 300 is a member that is arranged outside the plurality of power storage elements 100 and the plurality of spacers 200 and covers the plurality of power storage elements 100 and the like from above and below (from both sides in the Z-axis direction). The exterior body 300 is formed of an insulating member, a metal coated with an insulating coating, or the like. Exterior body 300 thereby prevents power storage element 100 and the like from coming into contact with external metal members and the like. Exterior body 300 may be formed of a conductive member such as metal, as long as the insulation of power storage element 100 and the like is maintained.

Exterior body 300 includes a tray 310 on which power storage elements 100 and the like are placed, and an insulating member 320 arranged above the plurality of power storage elements 100 (in the Z-axis positive direction). The tray 310 and the insulating member 320 may be made of the same material, or may be made of different materials.

The tray 310 is a box-shaped member with a shallow depth in the Z-axis direction. The tray 310 is made of an electrically insulating material (insulating material). The tray 310 may be formed of metal coated with an insulating coating. A plurality of power storage elements 100 and a plurality of spacers 200 are placed on the tray 310. More specifically, as shown in FIG. 3, the tray 310 has a plurality of partitions 315 inserted between the lower ends of two power storage elements 100 adjacent in the Y-axis direction. Movement of each of the plurality of power storage elements 100 in the Y-axis direction is restricted by at least one partition 315. This suppresses misalignment in the Y-axis direction between the gas exhaust valve 131 of each of the plurality of power storage elements 100 and the opening 322 of the insulating member 320 located at a position facing the gas exhaust valve 131. Details of the flow of gas discharged from the gas discharge valve 131 will be described later.

The insulating member 320 is a member that is disposed in the Z-axis plus direction of the plurality of power storage elements 100 and the plurality of spacers 200 and is elongated in the Y-axis direction and placed on the plurality of power storage elements 100. Since the insulating member 320 is disposed between the cover member 520 of the support body 500 and the power storage element 100, which will be described later, it can also be said to be the inner lid of the power storage unit 10. In this embodiment, the insulating member 320 is a busbar frame (also referred to as a busbar holder or a busbar plate), and performs insulation between the busbar 400 and other members, and regulates the position of the busbar 400. Specifically, the insulating member 320 is placed on the plurality of power storage elements 100 and positioned with respect to the plurality of power storage elements 100, and the plurality of bus bars 400 is positioned with respect to the insulating member 320. Thereby, each bus bar 400 is positioned with respect to the plurality of power storage elements 100 and joined to the electrode terminal 140 that the plurality of power storage elements 100 have.

The material for forming the insulating member 320 is as follows. 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 the like Examples include insulating members such as composite materials, or metals coated with an insulating coating.

The bus bar 400 is a rectangular plate-like member that is disposed on the plurality of power storage elements 100 and electrically connects the electrode terminals 140 of the plurality of power storage elements 100. In this embodiment, bus bar 400 and electrode terminal 140 are connected (joined) by bolt fastening, but may be connected (joined) by welding or the like. The bus bar 400 is formed of a metal conductive member such as aluminum, aluminum alloy, copper, copper alloy, nickel, or a combination thereof, or a conductive member other than metal. In this embodiment, bus bar 400 connects 14 power storage elements 100 in series by connecting electrode terminals 140 of adjacent power storage elements 100 to each other. The connection mode of power storage element 100 is not limited to the above, and series connection and parallel connection may be combined in any manner.

By connecting the electrode terminals 140 of the power storage elements 100 located at both ends in the Y-axis direction among the plurality of power storage elements 100 to the cables 410 and 420 (see FIG. 1), the power storage device 1 is protected from external power. It can charge electricity and discharge electricity to the outside. Cables 410 and 420 are electric wires (power cables) on the positive and negative sides through which current (main current) for charging and discharging power storage device 1 (power storage element 100) flows.

The support body 500 is a member that supports and protects (reinforces) the exterior body 300. The support body 500 is formed of a metal member such as stainless steel, iron, or galvanized steel plate. The support body 500 includes a support body 510 that constitutes the main body of the support body 500 and a cover member 520 that constitutes the lid body of the support body 500. The support body 510 and the cover member 520 may be made of the same material, or may be made of different materials.

The support body 510 is a member that supports the tray 310 on which the plurality of power storage elements 100 are placed from below (Z-axis negative direction), and includes a bottom portion 511 and connection portions 512 and 513. The bottom portion 511 is a flat rectangular portion that constitutes the bottom portion of the power storage unit 10 and extends in the Y-axis direction and parallel to the XY plane, and is arranged in the negative Z-axis direction of the tray 310. The connecting portion 512 is a plate-shaped portion that stands upright in the Z-axis positive direction from the Y-axis negative end of the bottom portion 511 and protrudes in the Y-axis negative direction, and is connected to the cover member 520 . The connecting portion 513 is a plate-shaped portion that stands upright in the Z-axis positive direction from the end of the bottom portion 511 in the Y-axis positive direction and protrudes in the Y-axis positive direction, and is connected to the cover member 520 .

The cover member 520 is a member disposed above the insulating member 320 (in the positive Z-axis direction), and includes a top surface portion 520a and connection portions 522 and 523. The top surface portion 520a is a flat, rectangular portion that constitutes the top surface portion (outer cover) of the power storage unit 10 and extends in the Y-axis direction and parallel to the XY plane, and extends in the Z-axis positive direction of the insulating member 320. will be placed in The connecting portion 522 is a portion that extends in the negative Z-axis direction from the end of the top surface portion 520a in the negative Y-axis direction and projects in the negative Y-axis direction, and is connected to the connecting portion 512 of the support body 510. The connecting portion 523 is a portion that extends from the end of the top surface portion 520a in the Y-axis positive direction in the Z-axis negative direction and projects in the Y-axis positive direction, and is connected to the connecting portion 513 of the support body 510.

In this way, the support body 510 and the cover member 520 are connected with the connecting portions 512 and 513 and the connecting portions 522 and 523 with screws or the like (joined together) with the tray 310 and the insulating member 320 sandwiched therebetween from the Z-axis direction. ) is configured to be fixed. Thereby, the support body 500 supports (holds) the exterior body 300.

Power storage device 1 according to the present embodiment further includes an exhaust duct 350, as shown in FIG. When gas is discharged from one or more power storage elements 100, the gas is guided to exhaust duct 350 and is discharged to the outside of power storage device 1. Specifically, gas is exhausted from an opening (gas exhaust port 358) provided at the end of the exhaust duct 350 in the Y-axis positive direction.

In this manner, exhaust duct 350 is a member that can guide the gas to the outside of power storage device 1 when gas is exhausted from one or more power storage elements 100 . In this embodiment, the exhaust duct 350 includes a first duct member 360 and a second duct member 521 that are aligned in the vertical direction (Z-axis direction). The first duct member 360 is an elongated member in the Y-axis direction, and has a plurality of through holes 362, as shown in FIG. The first duct member 360 is made of metal such as galvanized steel plate, for example. A first cylindrical portion 323 provided in the insulating member 320 is inserted into each of the plurality of through holes 362 . Second duct member 521 is a part of cover member 520 in this embodiment. That is, the second duct member 521 is also formed of metal such as a galvanized steel plate. As shown in FIG. 3, the exhaust duct 350 has an end wall portion that blocks the gas flow path at the end opposite to the gas exhaust port 358 (see FIGS. 1 and 2) (Y-axis negative direction). It has 359. In this way, the end of the internal space of the exhaust duct 350 in the negative Y-axis direction is closed by the end wall 359. As a result, the gas inside the exhaust duct 350 is exhausted from the gas exhaust port 358 (see FIGS. 1 and 2) provided at the end in the positive direction of the Y-axis. Details of the configuration of the exhaust duct 350 and its surroundings will be described later using FIGS. 5 to 7.

[2. Description of energy storage element]
Next, the configuration of power storage element 100 will be described in detail. FIG. 4 is a perspective view showing the appearance of power storage element 100 according to the embodiment. As shown in FIG. 4, the power storage element 100 includes a container 110 and a pair (positive electrode side and negative electrode side) of electrode terminals 140. Inside the container 110, an electrode body, a pair of current collectors (positive electrode side and negative electrode side), electrolyte solution (non-aqueous electrolyte), etc. are housed, but illustration of these is omitted. The type of electrolytic solution is not particularly limited as long as it does not impair the performance of power storage element 100, and various types can be selected. Although the power storage element 100 includes an insulating gasket that insulates and seals between the container 110, the electrode terminal 140, and the current collector, illustration of this gasket is also omitted.

In addition to the above-described components, the power storage element 100 may include a spacer disposed on the side or below the electrode body, an insulating film that wraps around the electrode body, and the like. An insulating film (such as a shrink tube) may be placed around the container 110 to cover the outer surface of the container 110.

The container 110 is a rectangular parallelepiped-shaped (square or box-shaped) case that includes a container body 120 in which an opening is formed, and a lid portion 130 that closes the opening of the container body 120. The container body 120 is a rectangular cylindrical member having a bottom and forming the main body portion of the container 110, and has an opening formed in the positive direction of the Z-axis. The lid portion 130 is a rectangular plate-like member that constitutes the lid of the container 110, and is arranged to extend in the X-axis direction in the Z-axis plus direction of the container body 120. The container 110 (lid 130) includes a gas discharge valve 131 that releases the pressure when the pressure inside the container 110 increases excessively, and a liquid injection valve for injecting electrolyte into the inside of the container 110. (not shown), etc. are provided.

The material of the container 110 (container main body 120 and lid part 130) is not particularly limited, and may be a weldable (joinable) metal such as stainless steel, aluminum, aluminum alloy, iron, or plated steel plate, but resin You can also use The container 110 has a structure in which the electrode body and the like are housed inside the container body 120, and then the container body 120 and the lid portion 130 are joined by welding or the like, thereby sealing the inside. The container 110 has a pair of long sides 111, a pair of short sides 112, and a bottom 113. In the present embodiment, the plurality of power storage elements 100 are arranged in a line in the Y-axis direction with the short sides 112 facing the X-axis direction and the gas exhaust valves 131 facing the Z-axis positive direction. (See Figure 3). The Z-axis plus direction is an example of the first direction, and the X-axis direction is an example of the second direction.

The electrode terminal 140 is a terminal member (a positive electrode terminal and a negative electrode terminal) of the electricity storage element 100 arranged in the lid part 130, and is electrically connected to the positive electrode plate and the negative electrode plate of the electrode body via the current collector. There is. The electrode terminal 140 is made of aluminum, aluminum alloy, copper, copper alloy, or the like.

The electrode body is a power storage element (power generation element) formed by laminating a positive electrode plate, a negative electrode plate, and a separator. The positive electrode plate has a positive electrode active material layer formed on a positive electrode base material layer, which is a current collector foil made of metal such as aluminum or an aluminum alloy. The negative electrode plate has a negative electrode active material layer formed on a negative electrode base material layer which is a current collecting foil made of metal such as copper or copper alloy. As the active material used for the positive electrode active material layer and the negative electrode active material layer, any known material can be used as appropriate as long as it is capable of intercalating and deintercalating lithium ions. As the separator, a microporous sheet made of resin, a nonwoven fabric, or the like can be used. In this embodiment, the electrode body is formed by stacking electrode plates (a positive electrode plate and a negative electrode plate) in the Y-axis direction. In addition, the electrode body is a wound type electrode body formed by winding electrode plates (positive electrode plate and negative electrode plate), and a laminated type (stack type) formed by laminating a plurality of flat electrode plates. The electrode body may be in any form, such as an electrode body or a bellows-shaped electrode body in which an electrode plate is folded into a bellows shape.

The current collectors are conductive members (a positive electrode current collector and a negative electrode current collector) that are electrically connected to the electrode terminal 140 and the electrode body. The positive electrode current collector is formed of aluminum or an aluminum alloy, etc., like the positive electrode base material layer of the positive electrode plate, and the negative electrode current collector is formed of copper, copper alloy, etc., like the negative electrode base material layer of the negative electrode plate. There is.

[3. Regarding the configuration of the exhaust duct and its surroundings]
Next, the configuration of the exhaust duct 350 and its surroundings according to the present embodiment will be described in detail with reference to FIGS. 5 to 7. FIG. 5 is a perspective view showing the positional relationship among the exhaust duct 350, the insulating member 320, and the plurality of power storage elements 100 according to the embodiment. In FIG. 5, illustrations of the bus bar 400, spacer 200, etc. are omitted. FIG. 6 is an enlarged perspective view showing a portion of the first duct member 360 and the insulating member 320 according to the embodiment. FIG. 7 is a perspective cross-sectional view showing the configuration of the exhaust duct 350 and its surroundings according to the embodiment. In FIG. 7, a cross section of the exhaust duct 350 and the insulating member 320 in the XZ plane passing along the line VII-VII in FIG. 5 is illustrated, and the power storage element 100 is illustrated in a perspective view rather than a cross-sectional view.

As shown in FIGS. 5 to 7, in this embodiment, the plurality of power storage elements 100 are arranged in the Y-axis direction, and as a result, the gas discharge valves 131 of each of the plurality of power storage elements 100 are also arranged in the Y-axis direction. are arranged in The exhaust duct 350 is formed in a long shape in the Y-axis direction along the plurality of gas exhaust valves 131. Specifically, an insulating member 320 is disposed above the plurality of power storage elements 100 (in the positive Z-axis direction, the same applies hereinafter), and an exhaust duct 350 is further disposed above the insulating member 320. An opening 322 of the insulating member 320 is located above the gas exhaust valve 131 of the power storage element 100, and when gas is discharged from the gas exhaust valve 131, it passes through the opening 322 and enters the inside of the exhaust duct 350. flows into.

More specifically, as shown in FIGS. 5 to 7, insulating member 320 has an insulating main body portion 321 that forms a partition wall between power storage element 100 and exhaust duct 350. The insulating main body portion 321 is provided with an opening 322 that penetrates in the vertical direction (Z-axis direction). The insulating member 320 further includes a first cylindrical portion 323 that projects upward from the insulating main body portion 321 and forms a space that communicates with the opening 322 . A through hole 362 is provided in a facing surface portion 361 of the exhaust duct 350 that forms a surface facing the power storage element 100 . The first cylindrical portion 323 of the insulating member 320 is disposed so as to pass through the through hole 362 of the exhaust duct 350.

In this embodiment, insulating member 320 is provided with 14 sets of openings 322 and first cylindrical portion 323 corresponding to 14 power storage elements 100 , and 14 pairs of openings 322 and first cylindrical portions 323 are provided in opposing surface portion 361 of exhaust duct 350 . A through hole 362 is provided. An upper wall portion 521a (see FIG. 7) is located above the opposing surface portion 361, and is provided between the opposing surface portion 361 and the upper wall portion 521a along the direction in which the plurality of power storage elements 100 are arranged (Y-axis direction). In addition, a gas flow path is formed. In other words, even if the gas exhaust valve 131 of any of the 14 energy storage elements 100 is opened (opened), the gas discharged from the gas exhaust valve 131 will be discharged from the exhaust duct 350. Flow inside. Gas inside the exhaust duct 350 is exhausted from a gas exhaust port 358 (see FIG. 2), and is led to a predetermined location via, for example, a gas hose (not shown).

As described above, power storage device 1 according to the present embodiment includes power storage element 100, exhaust duct 350, and insulating member 320 disposed between exhaust duct 350 and power storage element 100. The power storage element 100 is arranged in such a manner that a gas discharge valve 131 capable of discharging internal gas is oriented in a first direction (Z-axis positive direction). Exhaust duct 350 is disposed on the positive Z-axis side of power storage element 100 and forms a flow path for gas exhausted from gas exhaust valve 131. The exhaust duct 350 has a metal opposing surface portion 361 that forms a surface facing the power storage element 100 and has a through hole 362 formed at a position facing the gas exhaust valve 131 . The insulating member 320 has an insulating main body part 321 and a first cylindrical part 323. Insulating main body portion 321 is located between opposing surface portion 361 of exhaust duct 350 and power storage element 100. An opening 322 is formed in the insulating main body 321 at a position between the gas exhaust valve 131 and the through hole 362. The first cylindrical portion 323 forms a space communicating with the opening 322, and projects into the interior of the exhaust duct 350 through the through hole 362 of the exhaust duct 350, as shown in FIGS. 6 and 7.

In this manner, in this embodiment, the first cylindrical portion 323 located in front of the gas exhaust valve 131 of the power storage element 100 protrudes to the inside of the exhaust duct 350. Thereby, gas discharged from power storage element 100 efficiently flows into exhaust duct 350. Furthermore, since at least the facing surface portion 361 of the exhaust duct 350 is made of metal, there is a low possibility that it will be melted or deformed due to heat. Further, although the metal facing surface portion 361 is the closest portion of the exhaust duct 350 to the power storage element 100, electrical insulation from the power storage element 100 is ensured by the insulating main body portion 321. Furthermore, since the first cylindrical portion 323 is formed to a size that protrudes into the inside of the exhaust duct 350, the creepage distance between the power storage element 100 and the opposing surface portion 361 via the opening 322 of the insulating main body portion 321 is increased. is also relatively long. Furthermore, the structure in which first cylindrical portion 323 is inserted into through hole 362 facilitates positioning of insulating member 320 and exhaust duct 350 during manufacturing (assembling) of power storage device 1. This contributes to improving manufacturing efficiency. In this way, the power storage device 1 according to the present embodiment is a power storage device with a simple configuration and improved safety.

In this embodiment, the opposing surface portion 361 of the exhaust duct 350 is placed in contact with the insulating main body portion 321 of the insulating member 320. In other words, the exhaust duct 350 is arranged in such a manner that the space above the insulating member 320 is not wasted. Since the facing surface portion 361 is in contact with the insulating main body portion 321, the exhaust duct 350 can also function as a member that restricts upward movement of the insulating member 320. Thereby, for example, it is possible to maintain a state in which the tip of the second cylindrical portion 324, which will be described later, is pressed against the power storage element 100. As a result, when gas is discharged from the gas discharge valve 131, there is a possibility that the gas leaks from the gap between the tip of the second cylindrical portion 324 and the lid portion 130 of the power storage element 100 (see FIG. 4). reduce

Specifically, the exhaust duct 350 according to the present embodiment includes a first duct member 360 made of metal including a facing surface portion 361, and an upper wall portion 521a facing the facing surface portion 361 in the first direction (see FIG. 7). A second duct member 521 made of metal and forming a second duct member 521.

Thus, in this embodiment, the portion of exhaust duct 350 that faces through hole 362 (upper wall portion 521a) is also made of metal. Therefore, the possibility of damage to exhaust duct 350 when power storage element 100 is opened is further reduced. Further, the exhaust duct 350 is manufactured by combining two members (the first duct member 360 and the second duct member 521) arranged in the vertical direction (Z-axis direction). Therefore, it is easy to manufacture the exhaust duct 350 that has a space therein that serves as a gas flow path.

More specifically, as shown in FIGS. 6 and 7, the first duct member 360 includes an opposing surface portion 361 and both ends of the opposing surface portion 361 in a second direction (X-axis direction) perpendicular to the first direction. It has side wall portions 365 erected from each side toward the second duct member 521. The second duct member 521 is a flat member connected to the pair of side walls 365.

The first duct member 360 having the above configuration can be manufactured, for example, by bending both ends of a sheet metal in the X-axis direction. Furthermore, the flat second duct member 521 can be manufactured by cutting a sheet metal to a predetermined size. In other words, the exhaust duct 350 according to this embodiment can be manufactured through a relatively easy process.

In the present embodiment, second duct member 521 is a part of cover member 520 arranged to cover power storage element 100, insulating member 320, and first duct member 360 from the Z-axis positive direction side.

In this way, since a part of the exhaust duct 350 is formed by a part of the cover member 520 that covers the power storage element 100 and the like, the power storage device 1 can be made smaller, more space-saving, or lighter. Specifically, for example, when the second duct member 521 is made of resin, a plate-like member made of a highly heat-resistant material such as mica or metal is arranged along the upper wall portion 521a facing the through hole 362. It is possible to do so. However, in this case, the height (width in the Z-axis direction) of power storage device 1 may increase, the weight of power storage device 1 may increase, or the like. Regarding this point, in this embodiment, since a part of the metal cover member 520 is used as the second duct member 521, problems such as an increase in the size and weight of the power storage device 1 are unlikely to occur.

In this embodiment, first duct member 360 is fixed to cover member 520 with a plurality of screws 529 (see FIG. 5). A portion of the cover member 520 that faces the first duct member 360 in the Z-axis direction is used as the second duct member 521. More specifically, as shown in FIGS. 6 and 7, a flange portion 368 is provided at each end of the pair of side wall portions 365 in the first direction (positive direction of the Z-axis). That is, the first duct member 360 has a pair of flange portions 368, and each of the pair of flange portions 368 is provided to protrude away from the other. A plurality of screw holes 369 are provided in the pair of flange portions 368, as shown in FIGS. 5 and 6. As shown in FIG. The screw 529 is screwed together. That is, the first duct member 360 is fixed to the cover member 520 by the plurality of screws 529.

The flange portion 368 used to fix the first duct member 360 to the cover member 520 is located outside the exhaust duct 350, not inside the exhaust duct 350, as shown in FIG. Thereby, the flange portion 368 does not obstruct the gas flow path inside the exhaust duct 350. Furthermore, even if the tip of the screw 529 protrudes from the screw hole 369 of the flange portion 368, the tip will not obstruct the gas flow path. The method of fixing the first duct member 360 to the cover member 520 is not limited to fastening with the screws 529. Welding, adhesion, press-fitting, caulking, or the like may be employed as the fixing method.

As shown in FIG. 7, the insulating member 320 according to the present embodiment has a second cylindrical portion 324 that protrudes on the opposite side to the first cylindrical portion 323. As shown in FIG. That is, the insulating member 320 further includes a second cylindrical portion 324 that protrudes from the opening 322 of the insulating main body portion 321 toward the gas exhaust valve 131, and has a gas flow path communicating with the first cylindrical portion 323. It has a second cylindrical portion 324 formed therein.

As described above, the insulating member 320 according to the present embodiment includes the second cylindrical portion 324 that protrudes from the insulating main body portion 321 toward the gas exhaust valve 131 of the power storage element 100. As a result, even if there is a gap between the gas exhaust valve 131 and the insulating main body part 321, the second cylindrical part 324 receives the gas, so that the gas discharged from the gas exhaust valve 131 can be efficiently exhausted. It is guided to the inside of the duct 350. The second cylindrical portion 324 comes into contact with the power storage element 100, thereby restricting the displacement of the insulating main body part 321 in the direction toward the power storage element 100 (Z-axis negative direction). In other words, the insulating main body portion 321 is maintained between the exhaust duct 350 and the power storage element 100 in the Z-axis direction. This substantially prevents the first cylindrical portion 323 from coming out of the through hole 362 even when power storage device 1 is subjected to impact or vibration.

In power storage device 1 according to the present embodiment, as shown in FIGS. 3 and 5, a plurality of power storage elements 100 are arranged side by side. Exhaust duct 350 extends along the direction in which the plurality of power storage elements 100 are arranged.

In other words, the configuration of the first cylindrical portion 323, the second cylindrical portion 324 of the insulating member 320, the through hole 362 of the exhaust duct 350, etc., regarding gas discharge processing when the power storage element 100 opens, They are provided corresponding to each of the elements 100. Therefore, the gas discharged from the gas discharge valve 131 of each of the plurality of power storage elements 100 is efficiently guided to the inside of the exhaust duct 350, and the gas discharged from the gas discharge port 358 provided at one end of the exhaust duct 350 is directed to the outside of the power storage device 1. is discharged. That is, in power storage device 1 according to the present embodiment, gas is exhausted all at once from one end of exhaust duct 350 extending along 100 rows of power storage elements, so that gas processing is easy.

[4. Description of modification]
Although the power storage device 1 according to the present embodiment has been described above, the present invention is not limited to the above embodiment. 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 scope equivalent to the scope of the claims. .

In the embodiment described above, the exhaust duct 350 is formed of two members (the first duct member 360 and the second duct member 521) arranged in the vertical direction (Z-axis direction). However, there is no particular limitation on the number of members forming exhaust duct 350 included in power storage device 1. For example, one metal cylindrical member may be arranged in power storage device 1 as exhaust duct 350. The pair of walls of the exhaust duct 350 that face each other in the Z-axis direction and the pair of walls that face each other in the X-axis direction may be formed of separate members. That is, the exhaust duct 350 may be formed by combining four members. The shape of the cross section (cross section perpendicular to the extending direction) of the exhaust duct 350 does not need to be rectangular, and may be circular, elliptical, or polygonal other than rectangular. The second duct member 521 does not need to be part of the cover member 520. A member separate from cover member 520 may be disposed in power storage device 1 as second duct member 521.

In the embodiment described above, the insulating member 320 is a busbar frame, but it is not essential that the insulating member 320 have a portion that holds (fixes) the busbar 400. The insulating member 320 includes at least an insulating main body part 321 located between the exhaust duct 350 and the power storage element 100 and having an opening 322 , and a first cylindrical part 323 forming a space communicating with the opening 322 . It is sufficient if it has the following. As long as the insulating member 320 has the insulating main body part 321 and the first cylindrical part 323, the insulating member 320 may have a part for holding (fixing) an electrical device such as a control circuit board, It does not need to have a part for holding (fixing) equipment or the like.

The insulating member 320 does not need to have the second cylindrical portion 324. For example, the lower surface of the insulating main body portion 321 and the upper surface of the lid portion 130 (see FIG. 4) of the plurality of power storage elements 100 may be in contact with each other. In other words, the insulating main body portion 321 may be sandwiched between the exhaust duct 350 and the power storage element 100 even when the second cylinder portion 324 is not included. In this case, the lower surface of the insulating main body portion 321 and the upper surface of the lid portion 130 of the power storage element 100 may be adhered with adhesive, double-sided tape, or the like. Thereby, when gas is discharged from the gas discharge valve 131, the possibility that the gas leaks from the gap between the insulating main body portion 321 and the lid portion 130 of the power storage element 100 is reduced.

In the embodiment described above, the tray 310 and the insulating member 320 form an exterior body 300 that covers the plurality of power storage elements 100 and the like from above and below (from both sides in the Z-axis direction). However, the combination of tray 310 and insulating member 320 does not need to be treated as an "exterior body." For example, in the present embodiment, support body 500 (see FIGS. 1 and 3) that covers exterior body 300 from above and below may be treated as the “exterior body” of power storage device 1 or power storage unit 10.

Power storage device 1 does not need to be elongated in the direction in which the plurality of power storage elements 100 are arranged (Y-axis direction). For example, when the number of power storage elements 100 included in power storage device 1 is small (for example, 4 or less), the length of power storage device 1 in the Y-axis direction may be equal to or less than the length in the X-axis direction.

Embodiments constructed by arbitrarily combining the components included in the above embodiments and their modifications are also included within the scope of the present invention.

INDUSTRIAL APPLICATION This invention is applicable to the electrical storage device etc. which are equipped with electrical storage elements, such as a lithium ion secondary battery.

1 Power storage device 10 Power storage unit 100 Power storage element 131 Gas exhaust valve 320 Insulating member 321 Insulating main body 322 Opening 323 First cylindrical part 324 Second cylindrical part 350 Exhaust duct 358 Gas discharge port 359 End wall 360 First duct member 361 Opposing surface portion 362 Through hole 365 Side wall portion 368 Flange portion 520 Cover member 520a Top surface portion 521 Second duct member 521a Upper wall portion

Claims (6)

a power storage element arranged with a gas discharge valve capable of discharging internal gas facing in a first direction;
an exhaust duct that is disposed on the first direction side of the electricity storage element and forms a flow path for gas exhausted from the gas exhaust valve;
an insulating member disposed between the exhaust duct and the electricity storage element,
The exhaust duct is
a metal opposing surface portion forming a surface facing the electricity storage element, the opposing surface portion having a through hole formed at a position facing the gas exhaust valve;
The insulating member is
an insulating main body portion located between the opposing surface portion and the power storage element and having an opening formed at a position between the gas exhaust valve and the through hole;
a first cylindrical part forming a space communicating with the opening, the first cylindrical part penetrating the through hole and protruding into the inside of the exhaust duct;
Power storage device. The exhaust duct is
a first duct member made of metal including the opposing surface portion;
a second duct member made of metal forming an upper wall portion facing the opposing surface portion in the first direction;
The power storage device according to claim 1. The first duct member includes the opposing surface portion and side wall portions that extend toward the second duct member from both ends of the opposing surface portion in a second direction perpendicular to the first direction. death,
The second duct member is a flat member connected to the pair of side walls,
The power storage device according to claim 2. The second duct member is a part of a cover member arranged to cover the electricity storage element, the insulating member, and the first duct member from the first direction side.
The power storage device according to claim 3. The insulating member further includes a second cylindrical portion protruding from the opening of the insulating main body toward the gas exhaust valve, the second cylindrical portion forming a gas flow path communicating with the first cylindrical portion. having two cylindrical parts,
The power storage device according to any one of claims 1 to 4. A plurality of the power storage elements are arranged in a row,
The exhaust duct extends along the direction in which the plurality of power storage elements are arranged.
The power storage device according to any one of claims 1 to 4.

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