Power storage device

Abstract

This power storage device (10) comprises a power storage element (210) having an electrode terminal (210b), an exterior body (100) that accommodates the power storage element (210), and a first plate-form member (231). The exterior body (100) has a bottom wall (111), which is an installation-surface-side wall on which the power storage device (10) is installed. The first plate-form member (231) is arranged inside the exterior body (100) and is arranged at the end part of the power storage element (210) in a first direction, which is the direction in which the power storage element (210) and the bottom wall (111) are aligned. The power storage element (210) is arranged in an orientation in which the electrode terminal (210b) is oriented toward a second direction that intersects the first direction and that follows along the bottom wall (111). The first plate-form member (231) has a first protruding part (235) that protrudes beyond the power storage element (210) in the negative direction along the Y-axis .

Description

[Technical Field]

[0001] The present invention relates to an energy storage device including an energy storage element and an exterior body that houses the energy storage element. [Background technology]

[0002] Patent Document 1 discloses an energy storage device including a plurality of energy storage elements arranged in a first direction and an exterior housing that houses the plurality of energy storage elements. In this energy storage device, an end plate is disposed on each of the plurality of energy storage elements at the end in the first direction, abutting the side surface of the energy storage element in the first direction. The end plate has a lid abutment portion that abuts against the lid of the container for the energy storage element. This prevents the lid from tilting or deforming relative to the container body. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Publication No. 2019-79599 Summary of the Invention [Problem to be solved by the invention]

[0004] In the above-described conventional power storage device, a problem arises as to how to protect the power storage device from external forces.

[0005] An object of the present invention is to provide a power storage device that can improve safety. [Means for solving the problem]

[0006] An energy storage device according to one embodiment of the present invention is an energy storage device comprising: an energy storage element having electrode terminals; an exterior body that houses the energy storage element, the exterior body having an exterior body main body with an opening and a lid body that covers the opening, the exterior body main body having a bottom wall portion facing the lid body; and a first plate-shaped member that is disposed inside the exterior body and is disposed at an end of the energy storage element in a first direction that is the alignment direction of the energy storage element and the bottom wall portion, the energy storage element is disposed in an orientation in which the electrode terminals are facing in a second direction that intersects the first direction and is a direction along the bottom wall portion, and the first plate-shaped member has a first protrusion that protrudes further than the energy storage element in the second direction. [Effects of the Invention]

[0007] The power storage device according to the present invention can improve safety. [Brief explanation of the drawings]

[0008] [Figure 1] FIG. 1 is a perspective view showing the appearance of a power storage device according to an embodiment. [Figure 2] FIG. 2 is a perspective view showing the inside of the exterior body with the main body and the lid of the exterior body separated in the electricity storage device according to the embodiment. [Figure 3] FIG. 3 is an exploded perspective view showing components inside the exterior body of the power storage device according to the embodiment. [Figure 4] FIG. 4 is an exploded perspective view showing the components of the energy storage element unit according to the embodiment. [Figure 5] FIG. 5 is a perspective view showing the positional relationship between the first and second protruding portions, the energy storage elements, and the bus bar according to the embodiment. [Figure 6] FIG. 6 is a side view corresponding to FIG. [Figure 7] FIG. 7 is a perspective view showing the configuration of a first opening and its periphery according to the embodiment. [Figure 8] FIG. 8 is an exploded perspective view showing the structural relationship between the first plate-shaped member and the bus bar frame according to the embodiment. [Figure 9]FIG. 9 is a cross-sectional view of a state in which the first plate-shaped member and the bus bar frame according to the embodiment are combined. DETAILED DESCRIPTION OF THE INVENTION

[0009] The conventional energy storage device described above employs a structure in which a portion of an end plate presses down on a lid of a container for an energy storage element, thereby preventing damage to the container for the energy storage element due to container expansion. However, structural defects in the energy storage device are caused not only by the behavior of the energy storage element housed inside the exterior body, but also by vibrations or impacts applied from outside the exterior body. Therefore, when a large external force is applied to the exterior body in a collision accident or the like involving a vehicle equipped with the energy storage device, how to protect the energy storage device from the external force becomes an issue.

[0010] In the conventional energy storage devices described above, the energy storage elements are housed in the exterior body with their electrode terminals facing upward. However, in order to reduce the height (vertical width) of the energy storage device, the energy storage elements may be placed sideways (with their electrode terminals facing sideways). In other words, conductive members such as the electrode terminals may be oriented in a direction that makes them more susceptible to impact in the event of a collision or other accident. In such cases, how to ensure safety becomes an issue. Of course, the mechanical strength of the exterior body can be improved by placing a metal body on the inner surface of the exterior body facing the electrode terminals of the energy storage elements. However, in this case, the electrode terminals, bus bars, and the like are covered by the metal body, which raises another issue: how to ensure electrical safety.

[0011] An object of the present invention is to provide a power storage device that can improve safety.

[0012] An energy storage device according to one embodiment of the present invention is an energy storage device comprising: an energy storage element having electrode terminals; an exterior body that houses the energy storage element, the exterior body having an exterior body main body with an opening and a lid body that covers the opening, the exterior body main body having a bottom wall portion facing the lid body; and a first plate-shaped member that is disposed inside the exterior body and is disposed at an end of the energy storage element in a first direction that is the alignment direction of the energy storage element and the bottom wall portion, the energy storage element is disposed in an orientation in which the electrode terminals are facing in a second direction that intersects the first direction and is a direction along the bottom wall portion, and the first plate-shaped member has a first protrusion that protrudes further than the energy storage element in the second direction.

[0013] According to this configuration, in an energy storage device including horizontally placed energy storage elements, the first protrusion of the first plate-shaped member is positioned to protrude beyond the energy storage elements on the second direction side toward which the electrode terminals face. Therefore, if an object collides with the energy storage device from the second direction, the first protrusion protects the side of the energy storage element on which the electrode terminals are located. This reduces the possibility of an unsafe event, such as a short circuit, occurring due to the impact of a collision. The first plate-shaped member does not need to be positioned in a direction facing the electrode terminals (the second direction). In other words, even if the first plate-shaped member is made of a conductive material such as metal, there is little possibility of electrical conduction between the electrode terminals and the first plate-shaped member. Furthermore, when the long side of the energy storage element is oriented vertically, the first protrusion can be positioned anywhere along the long side of the energy storage element when viewed from the second direction (from the electrode terminal side). Therefore, there is a high degree of freedom in the position or range of the first protrusion. Thus, the energy storage device according to this aspect can improve safety.

[0014] The first protrusion may protrude beyond an end of the electrode terminal in the second direction.

[0015] This configuration more reliably protects the electrode terminals from external shocks to the power storage device, thereby improving the likelihood of preventing the electrode terminals from sinking into the container, thereby improving the safety of the power storage device.

[0016] The power storage device may further include a bus bar joined to the electrode terminal, and the first protrusion may be disposed to protrude further than the bus bar in the second direction.

[0017] This configuration protects the busbars and the electrode terminals to which the busbars are joined from impacts applied from outside the energy storage device, thereby improving the likelihood of preventing the busbars from damaging the energy storage elements or preventing the electrode terminals from being embedded in the container due to impacts received through the busbars, thereby improving the safety of the energy storage device.

[0018] The first protrusion may protrude in the second direction beyond an end of a gas release valve provided on the energy storage element.

[0019] According to this configuration, the gas release valve is protected from shocks applied from outside the power storage device, thereby preventing the gas release valve from being opened by an external shock, which contributes to improved safety.

[0020] A second plate-shaped member may be arranged at the end opposite the first plate-shaped member across the energy storage element, and the second plate-shaped member may have a second protruding portion that protrudes further than the energy storage element in the second direction.

[0021] According to this configuration, the energy storage elements can be protected more reliably by the two plate-shaped members (first plate-shaped member and second plate-shaped member).

[0022] The first plate-shaped member and the second plate-shaped member may be arranged in a parallel orientation, and the first protruding portion and the second protruding portion may have the same length in the second direction.

[0023] According to this configuration, external force is applied equally to the two plate-shaped members (first plate-shaped member and second plate-shaped member), so that the energy storage elements can be protected even more reliably.

[0024] The first plate-shaped member may have a first opening through which an electric wire arranged on the second direction side of the energy storage element passes.

[0025] According to this configuration, even if the first plate-shaped member is positioned in a position that may obstruct the placement (wiring) of the electric wires, the electric wires can be led out to the outside of the first plate-shaped member through the first opening. This reduces the possibility of the electric wires being broken due to being pinched between the first plate-shaped member and the inner surface of the exterior body, and improves the flexibility of the layout of the electric wires. When the first plate-shaped member is viewed from the direction in which the first plate-shaped member and the energy storage elements are aligned, there is no need to provide space outside the first plate-shaped member for passing the electric wires, so providing such space does not increase the size of the energy storage device. Therefore, the energy storage device according to this aspect improves safety and improves the flexibility of the layout of the electric wires.

[0026] The first opening may be formed as a notch cut out from an edge of the first plate-shaped member.

[0027] According to this configuration, since the first opening is formed in a notch shape, it is easy to store the electric wires in the first opening (to have the electric wires pass through the first opening), which improves the degree of freedom in the layout of the electric wires and simplifies the wiring work.

[0028] The energy storage device may further include an insulating member arranged on the second direction side of the energy storage element, the insulating member having a second opening cut out from an edge, through which the electric wire passes, the second opening being arranged to overlap the first opening and formed in a shape that covers the inner surface of the first opening.

[0029] This configuration ensures more reliable electrical insulation between the first plate-shaped member, which is made of a conductive material such as metal, and the electric wire. By forming the insulating member from a material that is more flexible than metal, such as resin, damage to the electric wire due to interference between the inner surface of the first opening and the electric wire can be suppressed. This reduces the possibility of malfunctions and unsafe events caused by damage to the electric wire.

[0030] The storage element may be arranged at the very end of a storage element array formed by arranging a plurality of storage elements including the storage element, and the first plate-shaped member may be arranged outside the storage element array.

[0031] According to this configuration, the first opening is provided in the first plate-shaped member, which is an end plate. Therefore, even if the size of the first plate-shaped member is relatively large from the viewpoint of protecting the energy storage element array, the electric wires can be led out of the energy storage element array through the first opening, eliminating the need to route the electric wires around the first plate-shaped member. In other words, this improves safety and simplifies the wiring layout.

[0032] The first plate-shaped member may be arranged on the opposite side of the bottom wall portion with the energy storage element array interposed therebetween.

[0033] According to this configuration, the first opening is provided in the first plate-shaped member disposed above the energy storage element array, which is made up of a plurality of energy storage elements arranged in a vertical direction with their electrode terminals facing sideways. Therefore, wiring work can be easily performed with the energy storage element array and the first plate-shaped member housed inside the exterior body. In other words, safety is improved and wiring work is facilitated.

[0034] Hereinafter, with reference to the drawings, a description will be given of an energy storage device according to an embodiment of the present invention (including its modified examples). The embodiments described below are all comprehensive or specific examples. The numerical values, shapes, materials, components, component placement and connection configurations, manufacturing processes, and the order of manufacturing processes shown in the following embodiments are merely examples and are not intended to limit the present invention. In each drawing, dimensions and the like are not strictly illustrated. In each drawing, the same or similar components are designated by the same reference numerals.

[0035] In the following description and drawings, the longitudinal direction of the exterior body of the energy storage device, the arrangement direction of the energy storage element unit and the electrical equipment unit, the arrangement direction of the multiple side members, the opposing direction of the short side surfaces of the container of the energy storage element, and the arrangement direction of a pair of electrode terminals of one energy storage element are defined as the X-axis direction. The arrangement direction of the energy storage element and the bus bar or bus bar frame is defined as the Y-axis direction. The arrangement direction of the main body and the lid of the exterior body of the energy storage device, the arrangement direction of the pair of plate-shaped members, the arrangement direction of the energy storage element, the spacer, and the plate-shaped members, the opposing direction of the long side surfaces of the container of the energy storage element, the flattening direction of the energy storage element, the stacking direction of the electrode plates of the electrode body of the energy storage element, and the up-down direction are defined as the Z-axis direction. The X-axis, Y-axis, and Z-axis directions intersect each other (orthogonal in this embodiment). Depending on the usage mode, the Z-axis may not be the up-down direction; however, for convenience of explanation, the following description will be made assuming that the Z-axis direction is the up-down direction.

[0036] In the following description, the positive X-axis direction refers to the direction of the X-axis arrow, and the negative X-axis direction refers to the direction opposite to the positive X-axis direction. The same applies to the Y-axis and Z-axis. Expressions indicating relative directions or attitudes, such as parallel and perpendicular, also include cases where the direction or attitude is not strictly that. "Two directions are perpendicular" does not only mean that the two directions are completely perpendicular, but also means that the directions are substantially perpendicular, i.e., there is a difference of about a few percent.

[0037] (Embodiment) [1. General description of the power storage device] A schematic configuration of a power storage device 10 according to the present embodiment will be described with reference to Figs. 1 to 3. Fig. 1 is a perspective view showing the appearance of the power storage device 10 according to the embodiment. Fig. 2 is a perspective view showing the inside of the exterior body 100 of the power storage device 10 according to the embodiment, with the main body and the lid of the exterior body 100 separated. Fig. 3 is an exploded perspective view showing the components inside the exterior body 100 of the power storage device 10 according to the embodiment.

[0038] The power storage device 10 is a device that can charge with electricity from an external source and discharge electricity to the outside, and in this embodiment has a substantially rectangular parallelepiped shape. The power storage device 10 is a battery module (battery assembly) used for power storage, power supply, or the like. Specifically, the power storage device 10 is used as a battery for driving or starting engines of moving objects such as automobiles, motorcycles, personal watercraft, ships, snowmobiles, agricultural machinery, construction machinery, and electric railway vehicles. Examples of the above-mentioned automobiles include electric vehicles (EVs), hybrid electric vehicles (HEVs), plug-in hybrid electric vehicles (PHEVs), and gasoline-powered automobiles. Examples of the above-mentioned electric railway vehicles include electric trains, monorails, linear motor cars, and hybrid trains equipped with both a diesel engine and an electric motor. The power storage device 10 can also be used as a stationary battery for home use or as a power generator.

[0039] 1 to 3, the energy storage device 10 includes an exterior body 100, an energy storage element unit 200 housed in the exterior body 100, a bus bar frame 251, and an electric equipment unit 300. In addition to the above components, the energy storage device 10 may also include a connector or the like that is connected to the electric equipment unit 300 by an electric wire or the like to transmit signals to the outside.

[0040] The exterior body 100 is a box-shaped (approximately rectangular parallelepiped) container (module case) that constitutes the housing of the energy storage device 10. In other words, the exterior body 100 is disposed outside the energy storage element unit 200 and the electric equipment unit 300, fixes the energy storage element unit 200 and the electric equipment unit 300 in predetermined positions, and protects them from impacts and the like. The exterior body 100 is formed from an insulating material such as polycarbonate (PC), polypropylene (PP), polyethylene (PE), polystyrene (PS), polyphenylene sulfide resin (PPS), polyphenylene ether (PPE (including modified PPE)), polyethylene terephthalate (PET), polybutylene terephthalate (PBT), polyether ether ketone (PEEK), tetrafluoroethylene-perfluoroalkyl vinyl ether (PFA), polytetrafluoroethylene (PTFE), polyethersulfone (PES), ABS resin, or a composite material thereof, or a metal with an insulating coating. The exterior body 100 thereby prevents the energy storage element unit 200 and the electric equipment unit 300 from coming into contact with external metal members, etc. The exterior body 100 may be formed of a conductive member such as a metal, as long as electrical insulation is maintained between the exterior body 100 and the energy storage element unit 200, the electric equipment unit 300, etc.

[0041] The exterior body 100 has an exterior body main body 110 that forms the main body of the exterior body 100, and a lid body 120 that closes an opening on the top surface of the exterior body main body 110. The exterior body main body 110 is a rectangular cylindrical housing with a bottom that has an opening formed on the positive side of the Z axis, and houses the energy storage element unit 200 and the electric equipment unit 300. The exterior body main body 110 has a bottom wall portion 111 and four side wall portions 112.

[0042] The bottom wall 111 is a wall on the installation surface side on which the power storage device 10 is installed, and is a wall that forms the bottom surface of the exterior body main body 110, which is arranged on the negative Z-axis side of the exterior body main body 110. When the power storage device 10 is mounted on a vehicle such as an automobile, the power storage device 10 is installed with the bottom wall 111 of the exterior body 110 facing the installation surface inside the vehicle. The four side wall portions 112 are four flat, rectangular walls that are arranged on both sides in the X-axis direction and on both sides in the Y-axis direction of the exterior body main body 110, and form two short side surfaces on both sides in the X-axis direction and two long side surfaces on both sides in the Y-axis direction of the exterior body main body 110.

[0043] The lid 120 is a flat, rectangular member that closes the opening of the exterior body 110. The lid 120 is joined to the exterior body 110, preferably in an airtight or watertight manner, by adhesive, heat sealing, ultrasonic welding, laser welding, or the like. A pair of external terminals 130, which are a pair of module terminals (general terminals) on the positive and negative sides, are arranged on the lid 120 at both ends in the negative X-axis direction and in the Y-axis direction. The energy storage device 10 charges with electricity from the outside and discharges electricity to the outside via this pair of external terminals 130. The external terminals 130 are formed of a conductive metal member such as aluminum, an aluminum alloy, copper, or a copper alloy.

[0044] The energy storage element unit 200 is a component having one or more energy storage elements 210. In the energy storage element unit 200 according to this embodiment, the multiple energy storage elements 210 are arranged (stacked) in the Z-axis direction in a horizontally placed (laid on their sides) state and are also aligned in the X-axis direction. This allows the energy storage element unit 200 to have a shape that is flat in the Z-axis direction and elongated in the X-axis direction. Specifically, the energy storage element unit 200 has a configuration in which the multiple energy storage elements 210 aligned in the Z-axis and X-axis directions are sandwiched in the Z-axis and X-axis directions by a pair of plate-like members 230 and multiple (three) side members 240 together with a spacer 220. A bus bar frame 251 for positioning the multiple bus bars 250 is attached to the negative Y-axis side of the energy storage element unit 200. In this embodiment, the Z-axis direction is an example of a first direction, which is the alignment direction of the storage element 210 and the bottom wall portion 111 of the outer casing 100, and the negative Y-axis direction is an example of a second direction, which intersects the first direction and is along the bottom wall portion 111.

[0045] The electric device unit 300 includes an electric device 310, an attachment member 320, and a bus bar unit 330. The electric device 310 is an apparatus capable of monitoring the states of the energy storage elements 210 included in the energy storage element unit 200 and controlling the energy storage elements 210. The electric device 310 is electrically connected to the energy storage element unit 200 via electric wires (described later with reference to FIG. 7 ), thereby enabling detection of the voltages of the respective energy storage elements 210, etc. In this embodiment, the electric device 310 is a flat rectangular member disposed and attached to the energy storage element unit 200 in the positive direction of the X axis. The electric device 310 includes electric components such as a circuit board that monitors the charge / discharge states of the energy storage elements 210 and controls the charge / discharge of the energy storage elements 210, as well as shunt resistors and connectors. The electric device 310 has a configuration in which these electric components are housed in an insulating cover member. The mounting member 320 is a flat plate-like member that mounts the electric device 310 to the energy storage element unit 200. Specifically, the mounting member 320 is attached to a plate-like member 230 and a side member 240 (described later) that the energy storage element unit 200 has. In this embodiment, the mounting member 320 is attached to the plate-like member 230 and the side member 240 with four bolts 321.

[0046] The bus bar unit 330 has bus bars and relays, etc., and electrically connects the energy storage element unit 200 to the electric device 310, electrically connects the electric device 310 to the external terminal 130, and electrically connects the energy storage element unit 200 to the external terminal 130. The bus bars are formed of a conductive member made of metal such as aluminum, an aluminum alloy, copper, a copper alloy, or nickel, or a combination of these, or a conductive member other than a metal.

[0047] [2. Configuration of Energy Storage Element Unit and Bus Bar Frame] The configurations of energy storage element unit 200 and bus bar frame 251 according to the embodiment will be described with reference to Fig. 4 in addition to Fig. 3. Fig. 4 is an exploded perspective view showing the components of energy storage element unit 200 according to the embodiment.

[0048] 3 and 4, the energy storage element unit 200 includes a plurality of energy storage elements 210, a plurality of spacers 220 (221, 222), a pair of plate-like members 230 (231, 232), and three side members 240. A bus bar frame 251 for positioning a plurality of bus bars 250 is arranged on the side of the energy storage element unit 200 toward which the electrode terminals 210b of the energy storage elements 210 face (the negative Y-axis side).

[0049] The energy storage element 210 is a secondary battery (single cell) that can charge and discharge electricity, and more specifically, is a nonaqueous electrolyte secondary battery such as a lithium-ion secondary battery. The energy storage element 210 includes a flat rectangular (square) container 210a, and an electrode assembly, a current collector, an electrolyte, and the like housed in the container 210a. The container 210a is a square case having a pair of long sides 215 and a pair of short sides 216. As shown in FIG. 4 , a pair of electrode terminals 210b (positive and negative) and a gas release valve 213 are arranged on a terminal arrangement surface 214, which is the side surface of the container 210a on the negative Y-axis direction.

[0050] The electrode body of the energy storage device 210 is an energy storage element (power generating element) having a positive electrode plate, a negative electrode plate, and a separator disposed between the positive electrode plate and the negative electrode plate. The positive electrode plate is a positive electrode substrate layer that is a current collecting foil made of a metal such as aluminum or an aluminum alloy, on which a positive electrode active material layer is formed. The negative electrode plate is a negative electrode substrate layer that is a current collecting foil made of a metal such as copper or a copper alloy, on which a negative electrode active material layer is formed. As the active material used for the positive electrode active material layer and the negative electrode active material layer, any known material capable of absorbing and releasing lithium ions can be used. Examples of such electrode bodies include a wound-type electrode body formed by winding electrode plates (positive electrode plate and negative electrode plate) around a winding axis (virtual axis), a stack-type electrode body formed by stacking multiple flat electrode plates, and a bellows-type electrode body formed by folding electrode plates in a bellows shape.

[0051] The electrode terminals 210b are terminals (positive and negative terminals) of the energy storage element 210, and are arranged on the container 210a so as to protrude in the negative Y-axis direction. The electrode terminals 210b are electrically connected to the positive or negative electrode plate of the electrode body via a current collector. The electrode terminals 210b are made of a conductive material such as a metal, such as aluminum, an aluminum alloy, copper, or a copper alloy.

[0052] The gas exhaust valve 213 provided in the container 210a is a part that opens (opens) in response to the internal pressure of the container 210a when the internal pressure of the container 210a rises excessively due to evaporation of the electrolyte inside the container 210a, thereby exhausting the gas from the container 210a.

[0053] In this embodiment, eight energy storage elements 210 configured as described above are placed horizontally (laying on their side) (with the long side surfaces 215 of the energy storage elements 210 facing the Z-axis direction) and arranged in the Z-axis and X-axis directions. Specifically, four energy storage elements 210 are arranged (stacked) in the Z-axis direction (arrangement direction) to form one energy storage element row 218. The energy storage element unit 200 has two of these energy storage element rows 218, and these two energy storage element rows 218 are arranged side by side in the X-axis direction.

[0054] The number of the energy storage elements 210 is not particularly limited, and any number of the energy storage elements 210 may be stacked (flat) in the Z-axis direction, or any number of the energy storage elements 210 may be arranged in the X-axis direction. That is, the energy storage element unit 200 may include only one energy storage element 210. The shape of the energy storage element 210 is not limited to the above-mentioned rectangular shape, and may be other shapes such as a polygonal column, a cylindrical column, an elliptical column, or an oblong column. The energy storage element 210 is not limited to a nonaqueous electrolyte secondary battery, and may be a secondary battery other than a nonaqueous electrolyte secondary battery, or may be a capacitor. The energy storage element 210 may not be a secondary battery, but may be a primary battery that can use stored electricity without the user having to charge it. The energy storage element 210 may be a battery using a solid electrolyte. The energy storage element 210 may be a pouch-type energy storage element.

[0055] The spacers 220 (221, 222) are flat, rectangular members that are arranged alongside the energy storage elements 210 in the Z-axis direction (arrangement direction) and electrically insulate the energy storage elements 210 from other members. The spacers 220 (221, 222) are made of any electrically insulating resin material or the like that can be used for the exterior body 100 described above.

[0056] Specifically, the spacers 221 are intermediate spacers (inter-cell spacers) arranged adjacent to the energy storage elements 210 in the Z-axis direction. That is, the spacers 221 are arranged between two adjacent energy storage elements 210, and electrically insulate the two energy storage elements 210 from each other.

[0057] The spacers 222 are end spacers arranged at the ends of the plurality of spacers 220 in the Z-axis direction (arrangement direction), and are arranged along the side surfaces in the Z-axis direction of the end storage elements 210. In other words, the spacers 222 are arranged on both sides in the Z-axis direction of the storage element row 218 made up of four storage elements 210.

[0058] Plate-shaped member 230 and side member 240 are members (restraining members) that compress (restrain) energy storage elements 210 from the outside in the Z-axis direction. That is, plate-shaped member 230 and side member 240 sandwich multiple energy storage elements 210 and multiple spacers 220 from both sides in the Z-axis direction, thereby compressing (restraining) each of energy storage elements 210 and multiple spacers 220 from both sides in the Z-axis direction. Plate-shaped member 230 and side member 240 are formed from metal members such as stainless steel, aluminum, aluminum alloy, iron, and plated steel plate, but may also be formed from an insulating member such as a highly rigid resin.

[0059] The plate-like members 230 (231, 232) are disposed at positions sandwiching the plurality of spacers 220 (221, 222) and the plurality of energy storage elements 210 in the Z-axis direction, and are a pair of flat plate-like members (end plates) that sandwich them in the Z-axis direction. This collectively applies a restraining force in the Z-axis direction to the plurality of energy storage elements 210 and the plurality of spacers 220 aligned in the Z-axis direction. In this embodiment, in order to distinguish between the two plate-like members 230 aligned in the Z-axis direction, the plate-like member 230 on the positive side of the Z-axis is referred to as a first plate-like member 231, and the plate-like member 230 on the negative side of the Z-axis is referred to as a second plate-like member 232. The side members 240 are attached at both ends in the Z-axis direction to the pair of plate-like members 230, and connect the pair of plate-like members 230 to restrain the plurality of energy storage elements 210 and the plurality of spacers 220. Specifically, a plurality of bolt holes 243 are provided on both end surfaces of the side member 240 in the Z-axis direction, and the first plate-shaped member 231 and the second plate-shaped member 232 are fastened to the pair of side members 240 by bolts 230a threaded into the respective bolt holes 243. Note that the method of connecting the plate-shaped member 230 and the side member 240 may be a method other than fastening using the bolts 230a, and may be welding, crimping, adhesion, welding, or the like.

[0060] In this embodiment, the first plate-shaped member 231 has a first protruding portion 235 that protrudes further than the energy storage element 210 in the direction in which the electrode terminal 210b of the energy storage element 210 is oriented (the negative Y-axis direction). The second plate-shaped member 232 similarly has a second protruding portion 236 that protrudes further than the energy storage element 210 in the negative Y-axis direction. The first plate-shaped member 231 also has a first opening 233 at its end in the negative Y-axis direction for passing an electric wire through. That is, the first plate-shaped member 231 has a first protruding portion 235 extending in the X-axis direction, and multiple first openings 233 are provided in the first protruding portion 235 that extends in the X-axis direction. This structure can be expressed as the first protruding portions 235 and the first openings 233 being arranged alternately in the X-axis direction. The first protruding portion 235 and the surrounding configuration will be described later using FIGS. 5 and 6. The first openings 233 and the surrounding configuration will be described later using FIGS. 7 to 9.

[0061] The bus bar 250 is a conductive member connected to the energy storage elements 210. Specifically, the bus bar 250 is arranged in the negative Y-axis direction of the multiple energy storage elements 210, and is connected (joined) to the electrode terminals 210b of the multiple energy storage elements 210 and the bus bar unit 330. In the present embodiment, the bus bar 250 and the electrode terminals 210b of the energy storage elements 210 are connected (joined) by welding, but may be connected (joined) by crimping, bolting, or the like. The bus bar 250 is formed of a conductive member made of a metal such as aluminum, an aluminum alloy, copper, a copper alloy, or nickel, or a combination thereof, or a conductive member other than a metal. In the present embodiment, the multiple bus bars 250 connect the energy storage elements 210 two by two in parallel, and connect four sets of the parallel-connected energy storage elements 210 in series. The manner in which the eight energy storage elements 210 are electrically connected by the bus bars 250 is not limited to this, and all eight energy storage elements 210 may be connected in series by a plurality of bus bars 250.

[0062] The bus bar frame 251 is an example of an insulating member and is a flat, rectangular member that electrically insulates the bus bar 250 from other members and can regulate the position of the bus bar 250. The bus bar frame 251 is formed of any electrically insulating resin material or the like that can be used for the above-described exterior housing 100. The bus bar frame 251 is disposed in the negative Y-axis direction of the multiple energy storage elements 210 and is positioned relative to the multiple energy storage elements 210. The multiple bus bars 250 are also positioned by the bus bar frame 251. As a result, each of the multiple bus bars 250 is positioned relative to the multiple energy storage elements 210 and joined to the electrode terminals 210b of the multiple energy storage elements 210. In the present embodiment, the bus bar frame 251 has a second opening 258. The second opening 258 is formed to overlap the first opening 233 of the first plate-like member 231 and cover the inner circumferential surface of the first opening 233. Details of the second opening 258 will be described later using FIGS. 7 to 9.

[0063] [3. Configuration of the protruding portion of the plate-like member and its surroundings] Next, the configuration of the first protruding portion 235, the second protruding portion 236 and the surrounding areas according to the embodiment will be described with reference to FIGS. 5 and 6 in addition to the above-mentioned FIGS.

[0064] Fig. 5 is a perspective view showing the positional relationship between first protrusion 235 and second protrusion 236 and energy storage element 210 and bus bar 250 according to the embodiment. Fig. 6 is a side view corresponding to Fig. 5. In Figs. 5 and 6, in order to clearly show the positional relationship between first protrusion 235 and second protrusion 236 and energy storage element 210 and bus bar 250, bus bar frame 251 and spacer 220 (221, 222) are omitted and only a portion of energy storage element unit 200 is shown.

[0065] As shown in FIGS. 2 to 4, 5, and 6, the energy storage device 10 according to this embodiment includes an energy storage element 210 having electrode terminals 210b, an exterior body 100 that houses the energy storage element 210, and a first plate-shaped member 231. The exterior body 100 has a bottom wall 111 (see FIG. 2) that is a wall on the installation surface side on which the energy storage device 10 is installed. The first plate-shaped member 231 is disposed inside the exterior body 100 and is disposed at an end of the energy storage element 210 in a first direction (Z-axis direction) in which the energy storage element 210 and the bottom wall 111 are aligned. The energy storage element 210 is disposed in an orientation in which the electrode terminals 210b are oriented in a second direction (Y-axis negative direction) that intersects the Z-axis direction and is along the bottom wall 111. As shown in FIGS. 5 and 6, the first plate-shaped member 231 has a first protrusion 235 that protrudes beyond the energy storage element 210 in the Y-axis negative direction.

[0066] As described above, in this embodiment, in an energy storage device 10 including energy storage elements 210 placed horizontally, the first protrusion 235 of the first plate-shaped member 231 is disposed to protrude beyond the energy storage elements 210 on the negative Y-axis direction toward which the electrode terminals 210b face. Therefore, if an object collides with the energy storage device 10 from the negative Y-axis direction, the first protrusion 235 protects the side of the energy storage elements 210 on which the electrode terminals 210b are disposed. This reduces the possibility of an unsafe event, such as a short circuit, occurring due to the impact of a collision. Furthermore, the first plate-shaped member 231 does not need to be disposed facing the electrode terminals 210b. That is, the first plate-shaped member 231, which is formed of a metal such as iron or an aluminum alloy, is unlikely to be electrically connected to the electrode terminals 210b. Furthermore, the first protrusion 235 can be disposed at any position along the long side of the energy storage elements 210 when viewed from the electrode terminals 210b side. That is, the position of the first protrusion 235 can be determined within a relatively wide range. Therefore, there is a high degree of freedom in the arrangement position or arrangement range of the first protrusion 235. In this way, according to the power storage device 10 of this embodiment, safety can be improved.

[0067] In this embodiment, the first protrusion 235 is located at the end of the electrode terminal 210b when the energy storage element 210 is viewed from the negative Y-axis direction. Specifically, as shown in Fig. 5, the first protrusion 235 is arranged on the positive Z-axis side of the multiple electrode terminals 210b arranged in the Z-axis direction in the energy storage element array 218.

[0068] This configuration can more reliably protect the electrode terminal 210b from impacts applied from outside the power storage device 10. This improves the possibility of preventing the electrode terminal 210b from sinking into the container 210a, thereby improving the safety of the power storage device 10.

[0069] In this embodiment, the energy storage device 10 is provided with a bus bar 250 joined to the electrode terminal 210b, and the first protrusion 235 is arranged to protrude further than the bus bar in the negative Y-axis direction, as shown in FIG. 6.

[0070] This configuration protects the bus bar 250 and the electrode terminal 210b joined to the bus bar 250 from an impact applied from outside the energy storage device 10. This improves the likelihood of preventing the bus bar 250 from damaging the energy storage element 210 or preventing the electrode terminal 210b, which has received an impact via the bus bar 250, from sinking into the inside of the container 210a, thereby improving the safety of the energy storage device 10.

[0071] In this embodiment, when the energy storage element 210 is viewed from the negative Y-axis direction, the first protrusion 235 is located at an end of the gas release valve 213 provided in the energy storage element 210. Specifically, as shown in Fig. 5 , the first protrusion 235 is arranged on the positive Z-axis side of the multiple gas release valves 213 arranged in the Z-axis direction in the energy storage element array 218.

[0072] This configuration protects the gas release valve 213 from impacts applied from outside the power storage device 10. This improves the possibility of avoiding an event in which the gas release valve 213 opens due to an external impact, thereby improving the safety of the power storage device 10.

[0073] In this embodiment, the energy storage device 10 further includes a second plate-shaped member 232 disposed at an end of the energy storage element 210 at a position different from that of the first plate-shaped member 231. The second plate-shaped member 232 has a second protruding portion 236 that protrudes beyond the energy storage element 210 in the negative Y-axis direction.

[0074] Specifically, in this embodiment, two storage element arrays 218 aligned in the X-axis direction are collectively restrained by a pair of plate-shaped members 230 (first plate-shaped member 231 and second plate-shaped member 232) facing each other in the Z-axis direction. In this configuration, the first plate-shaped member 231 has a first protruding portion 235 that protrudes beyond the storage element arrays 218, and the second plate-shaped member 232 has a second protruding portion 236 that protrudes beyond the storage element arrays 218.

[0075] Thus, in this embodiment, two plate-shaped members 230 (first plate-shaped member 231 and second plate-shaped member 232) are arranged to protrude toward electrode terminal 210b above and below one or more energy storage elements 210. Therefore, when an impact is applied from the electrode terminal 210b side of one or more energy storage elements 210 (eight energy storage elements 210 in this embodiment), these energy storage elements 210 can be more reliably protected.

[0076] In this embodiment, the first plate-shaped member 231 and the second plate-shaped member 231 are arranged in a parallel posture, and the first protruding portion 235 and the second protruding portion 236 have the same length in the second direction.

[0077] According to this configuration, external force is applied evenly to the two plate-shaped members 230 (first plate-shaped member 231 and second plate-shaped member 232), so that when an impact is applied from the electrode terminal 210b side of one or more storage elements 210 (eight storage elements 210 in this embodiment), these storage elements 210 can be protected even more reliably.

[0078] [4. Configuration of the first opening and its surrounding area] Next, the configuration of first opening 233 and its periphery according to the embodiment will be described with reference to FIGS. 7 to 9. FIG. 7 is a perspective view showing the configuration of first opening 233 and its periphery according to the embodiment. FIG. 8 is an exploded perspective view showing the structural relationship between first plate-shaped member 231 and bus bar frame 251 according to the embodiment. FIG. 9 is a cross-sectional view of first plate-shaped member 231 and bus bar frame 251 according to the embodiment in a combined state. FIG. 9 shows a cross section of part of first plate-shaped member 231 and bus bar frame 251 in the XY plane passing through line IX-IX in FIG. 8.

[0079] 7, in the energy storage device 10, an electric wire 340 for voltage detection is connected to the bus bar 250. A temperature detection section 260 including a thermistor element or the like is disposed in the energy storage element unit 200, and the electric wire 340 for temperature detection is connected to this temperature detection section 260. These electric wires 340 are extended to the above-mentioned electric device 310 (see FIG. 3), and the electric device 310 controls the charging and discharging of the energy storage element unit 200 based on the detected voltage, temperature, etc.

[0080] In this configuration, the bus bar 250 and other components to which the electric wires 340 are connected are disposed on the terminal arrangement surface 214 side (negative Y-axis side) of the energy storage element 210, so at least a portion of the electric wires 340 is disposed on the negative Y-axis side. However, to keep the electric wires 340 away from the heat of the energy storage element 210 or heat and spatter during bonding, and to ensure space for bonding the bus bar 250 to the electrode terminal 210b, it is preferable that the length of the electric wires 340 located on the negative Y-axis side be short. Furthermore, it is preferable to bundle multiple electric wires 340 into one as much as possible to facilitate wiring work. From this perspective, this embodiment employs a structure in which the multiple electric wires 340 located on the negative Y-axis side of the energy storage element 210 are routed from above the bus bar frame 251 in the positive Z-axis direction. In this case, the electric wires 340 need to pass over the first plate-like member 231. However, in this embodiment, a first protrusion 235 is disposed to improve safety, as shown in FIGS. 6 and 7 . Therefore, the first plate-shaped member 231 is provided with a first opening 233 for passing the electric wire 340 therethrough, as shown in FIGS.

[0081] That is, in the present embodiment, first plate-shaped member 231 has first opening 233 through which electric wire 340 arranged on the negative Y-axis direction side of energy storage element 210 passes.

[0082] According to this configuration, even if the first plate-shaped member 231 is disposed in a position that may obstruct the placement (wiring) of the electric wires 340, the electric wires 340 can be led out to the outside of the first plate-shaped member 231 through the first opening 233. This reduces the possibility of the electric wires 340 being broken due to being pinched between the first plate-shaped member 231 and the inner surface of the exterior body 100, and also improves the degree of freedom in the layout of the electric wires 340. When the first plate-shaped member 231 is viewed from the direction in which the first plate-shaped member 231 and the energy storage elements 210 are aligned, there is no need to provide a space outside the first plate-shaped member 231 for passing the electric wires 340. Therefore, providing such a space does not increase the size of the energy storage device 10. Therefore, the energy storage device 10 according to this embodiment improves safety and improves the degree of freedom in the layout of the electric wires 340.

[0083] In this embodiment, the first opening 233 is provided in the shape of a notch cut out from the edge of the first plate-shaped member 231, as shown in FIG.

[0084] In this way, since the first opening 233 is provided in a notch shape, it is easy to accommodate the electric wires 340 in the first opening 233 (to have the electric wires 340 pass through the first opening 233). In other words, the degree of freedom in the layout of the electric wires 340 is improved, and the wiring work is facilitated.

[0085] In this embodiment, as shown in FIG. 7, the energy storage device 10 includes an insulating member (bus bar frame 251) arranged on the negative Y-axis direction side of the energy storage elements 210. The bus bar frame 251 has second openings 258 cut out from an edge, through which the electric wires 340 pass. The second openings 258 are arranged to overlap the first openings 233 and are formed in a shape that covers the inner surfaces 233a (see FIG. 9) of the first openings 233. In other words, as shown in FIGS. 7 to 9, the second openings 258, which are part of the bus bar frame 251 made of an insulating material, are arranged to cover the inner surfaces 233a of the first openings 233 from the inside.

[0086] This configuration ensures more reliable electrical insulation between first plate-shaped member 231, which is made of a conductive material such as metal, and electric wire 340. By forming bus bar frame 251 from a resin that is more flexible than metal, damage to electric wire 340 due to interference between inner surface 233a of first opening 233 and electric wire 340 can be suppressed. This reduces the possibility of malfunctions and unsafe events caused by damage to electric wire 340.

[0087] In the present embodiment, first plate-shaped member 231 is arranged outside energy storage element array 218 formed by arranging a plurality of energy storage elements 210.

[0088] That is, in this embodiment, the first opening 233 is provided in the first plate-shaped member 231, which is an end plate. Therefore, even if the size of the first plate-shaped member 231 is made relatively large from the standpoint of protecting the energy storage element array 218, that is, even if the protrusion amount of the first protrusion 235 is made large, the electric wire 340 can be led out of the energy storage element array 218 through the first opening 233. Therefore, there is no need to arrange the electric wire 340 in a way that avoids the first plate-shaped member 231. In other words, safety is improved and the wiring layout is simplified.

[0089] In the present embodiment, first plate-shaped member 231 is arranged on the opposite side from bottom wall portion 111, with energy storage element array 218 sandwiched therebetween.

[0090] According to this configuration, the first opening 233 is provided in the first plate-shaped member 231 that is arranged above the energy storage element array 218, which is made up of a plurality of energy storage elements 210 that are arranged in the vertical direction with their electrode terminals 210b facing sideways. Therefore, wiring work can be easily performed with the energy storage element array 218 and the first plate-shaped member 231 housed inside the exterior body 100. In other words, safety is improved and wiring work is made easier.

[0091] [5. Modifications] Although the energy storage device 10 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 embodiment disclosed herein is illustrative in all respects and is not restrictive, and the scope of the present invention includes all modifications within the meaning and scope of the claims.

[0092] In the present embodiment, of the first plate-shaped member 231 and the second plate-shaped member 232, the first plate-shaped member 231 is disposed at a position far from the bottom wall portion 111 (see FIG. 2 ) of the exterior housing 100, and the second plate-shaped member 232 is disposed at a position close to the bottom wall portion 111. However, the positional relationship in the Z-axis direction between the first plate-shaped member 231 and the second plate-shaped member 232 may be reversed. That is, for an energy storage element 210 housed in the exterior housing 100 with its electrode terminals 210b oriented horizontally, the plate-shaped member located at the end of the arrangement direction of the bottom wall portion 111 and the energy storage element 210 only needs to have a protruding portion that protrudes beyond the energy storage element 210 in the direction in which the electrode terminals 210b face. This allows the protruding portion to exert an effect of protecting the energy storage element 210, thereby improving the safety of the energy storage device 10.

[0093] The first plate-shaped member and the second plate-shaped member, each having a protrusion, do not have to be arranged parallel to each other. Side member 240, which is arranged perpendicular to first plate-shaped member 231 having first protrusion 235, may have second protrusion 236 that protrudes further in the negative Y-axis direction than energy storage elements 210. Even in this case, at least two protrusions can protect multiple energy storage elements 210 over a relatively wide area.

[0094] 3 and 4 are merely examples of the positions, number, shapes, and arrangement ranges of the first protrusions 235 and the second protrusions 236, and are not limited by these figures. The second protrusions 236 may be dispersed along the edge of the second plate-shaped member 232 on the negative Y-axis direction side. Each of the first protrusions 235 and the second protrusions 236 may be arranged only in a portion close to the element (such as the electrode terminal 210b) for which protection is the highest priority.

[0095] A first plate-shaped member 231 having a first opening 233 may be disposed between the energy storage element array 218 and the bottom wall portion 111 of the exterior housing 100. Even in this case, by having a second opening 258 in a position where the bus bar frame 251 overlaps the first opening 233, the electric wire 340 can be wired between the bus bar 250 or the like on the negative Y-axis direction side of the energy storage element 210 and the electric device 310 without coming into direct contact with the first plate-shaped member 231.

[0096] The first opening 233 does not have to be formed as a notch from the edge of the first plate-shaped member 231. The first opening 233 may be formed in the first plate-shaped member 231 as a through-hole that penetrates the first plate-shaped member 231 in the thickness direction.

[0097] It is not essential that first opening 233 is provided in first plate-shaped member 231. When there is no need for electric wire 340 to pass over first plate-shaped member 231, such as when there is sufficient space on bus bar frame 251 to arrange electric wire 340, first plate-shaped member 231 does not need to have first opening 233.

[0098] The first plate-shaped member having the first protrusion 235 does not need to be an end plate that restrains a plurality of energy storage elements 210 (energy storage element array 218) aligned in the Z-axis direction, like the first plate-shaped member 231 according to the embodiment. The first protrusion 235 may be provided on the first plate-shaped member that is a spacer arranged along one of the side surfaces of the energy storage element array 218. Even in this case, the first protrusion 235 still provides a protective effect for one or more energy storage elements 210.

[0099] The energy storage element unit 200 may not have the spacer 221, which is an inter-cell spacer, when, for example, each of the containers 210a of the multiple energy storage elements 210 is wrapped in an insulating film. The energy storage element unit 200 may not have the spacer 222, which is an end spacer, regardless of whether the spacer 221 is present. In other words, it is not essential that the energy storage element unit 200 has the spacer 220. Even if the energy storage element unit 200 does not have the spacer 220, the first protrusion 235 of the first plate-shaped member 231 can still provide a protective effect for one or more energy storage elements 210.

[0100] Any combination of the components included in the above-described embodiments and their modifications is also included within the scope of the present invention. [Industrial Applicability]

[0101] The present invention can be applied to an electricity storage device including an electricity storage element such as a lithium ion secondary battery. [Explanation of symbols]

[0102] 10. Energy storage device 100 exterior body 111 Bottom wall 210 Energy storage element 210b Electrode terminal 214 Terminal arrangement surface 215 Long side 216 short side 218 Storage element array 230 Plate-like members 231 First plate-shaped member 232 Second plate-shaped member 233 First opening 233a Inner surface 235 First protrusion 236 Second protrusion 250 busbar 251 Busbar Frame 258 Second opening 260 Temperature detection unit 310 Electrical Equipment 340 Electric wire

Claims

1. an electricity storage element having an electrode terminal; An exterior body that houses the energy storage element, an exterior body having an opening and a lid that closes the opening; the exterior body main body has a bottom wall portion facing the lid body; a first plate-shaped member disposed inside the exterior body and disposed at an end of the energy storage element in a first direction that is an alignment direction of the energy storage element and the bottom wall portion, the energy storage element is disposed in a position in which the electrode terminals are oriented in a second direction that intersects the first direction and is a direction along the bottom wall portion, the first plate-shaped member has a first protruding portion that protrudes further than the energy storage element in the second direction, the first protrusion is disposed at a position aligned with the electrode terminal in the first direction and protrudes beyond an end of the electrode terminal in the second direction. Energy storage device.

2. further comprising a bus bar joined to the electrode terminal, the first protruding portion is disposed to protrude further than the bus bar in the second direction. The electricity storage device according to claim 1.

3. the first protruding portion protrudes in the second direction beyond an end of a gas release valve provided in the energy storage element; The electricity storage device according to claim 1 or 2.

4. Furthermore, a second plate-shaped member is disposed at an end opposite to the first plate-shaped member across the energy storage element, the second plate-shaped member has a second protruding portion that protrudes further than the energy storage element in the second direction; The electricity storage device according to any one of claims 1 to 3.

5. The first plate-shaped member and the second plate-shaped member are arranged in a parallel orientation to each other, The first protruding portion and the second protruding portion have the same length in the second direction. The electricity storage device according to claim 4.

6. an electricity storage element having an electrode terminal; An exterior body that houses the energy storage element, an exterior body having an opening and a lid that closes the opening; the exterior body main body has a bottom wall portion facing the lid body; a first plate-shaped member disposed inside the exterior body and disposed at an end of the energy storage element in a first direction that is an alignment direction of the energy storage element and the bottom wall portion, the energy storage element is disposed in a position in which the electrode terminals are oriented in a second direction that intersects the first direction and is a direction along the bottom wall portion, the first plate-shaped member has a first protruding portion that protrudes further than the energy storage element in the second direction, the first plate-shaped member has a first opening through which an electric wire arranged adjacent to the energy storage element in the second direction passes; Energy storage device.

7. The first opening is formed as a notch from an edge of the first plate-shaped member. The electricity storage device according to claim 6.

8. further comprising an insulating member disposed adjacent to the energy storage element in the second direction, the insulating member has a second opening formed in a notched shape from an edge thereof, the second opening allowing the electric wire to pass through; The second opening is disposed so as to overlap the first opening and is formed in a shape that covers the inner surface of the first opening. The electricity storage device according to claim 7.

9. the energy storage element is disposed at the end of a storage element row formed by arranging a plurality of energy storage elements including the energy storage element, the first plate-shaped member is disposed outside the energy storage element array, The electricity storage device according to any one of claims 6 to 8.

10. the first plate-shaped member is disposed on the opposite side of the bottom wall portion with the energy storage element array interposed therebetween; The electricity storage device according to claim 9.

Images