JP7552129B2 - Power storage device - Google Patents

Description

The present invention relates to an energy storage device that includes an energy storage element and a spacer.

Conventionally, there is known a storage device having a configuration including a storage element and a spacer, and a side member disposed adjacent to the spacer in a direction intersecting the arrangement direction of the storage element and the spacer. For example, Patent Document 1 discloses a battery module (storage device) having a configuration including a plurality of battery cells (storage elements) and spacers interposed between the plurality of battery cells, and a side plate (side member) disposed adjacent to the spacer.

JP 2017-174831 A

In an energy storage device having the above-described conventional configuration, it may be necessary to position the spacer relative to the side member. For example, in order to prevent the energy storage element from moving within the energy storage device due to vibration, impact, etc., it may be necessary to position the energy storage element within the energy storage device by positioning the spacer relative to the side member. In order to prevent poor bonding when bonding the energy storage element and the bus bar, it may be necessary to position the energy storage element by positioning the spacer relative to the side member at the time of bonding. However, a gap (clearance) may be provided between the side member and the spacer to absorb manufacturing tolerances, and this gap may cause the spacer to become misaligned relative to the side member.

The present invention was made by the inventors with a new focus on the above problem, and aims to provide an electricity storage device that can prevent the spacer from shifting from the side member.

To achieve the above object, an energy storage device according to one embodiment of the present invention is an energy storage device including an energy storage element and a spacer arranged side by side in a first direction, and including a side member arranged adjacent to the spacer in a second direction intersecting the first direction, the spacer having a first protrusion protruding toward a third direction intersecting the first direction and the second direction, and the side member having an opposing portion arranged opposite the first protrusion in the third direction.

According to this, in the energy storage device, the spacer aligned with the energy storage element in the first direction has a first protrusion protruding in the third direction, and the side member adjacent to the spacer in the second direction has an opposing portion opposing the first protrusion in the third direction. In this way, by providing the spacer with a first protrusion that protrudes in the third direction and faces the opposing portion of the side member, even if a gap is formed between the wall portion on which the first protrusion is provided and the opposing portion, the first protrusion can fill the gap. In other words, even if a gap (clearance) is provided in the third direction between the wall portion of the spacer and the opposing portion of the side member to absorb manufacturing tolerances, the first protrusion can prevent a gap from being formed between the spacer and the side member. This makes it possible to prevent the position of the spacer from being shifted relative to the side member.

The spacer may further have a wall portion facing the first protrusion in the third direction, the wall portion being disposed facing the opposing portion in the third direction, and the surface of the wall portion facing the opposing portion may have a shape that conforms to the opposing portion.

According to this, in the spacer, the surface of the wall portion facing the first protrusion, which faces the opposing portion, has a shape that conforms to the opposing portion. In this way, the wall portion facing the first protrusion of the spacer has a shape that conforms to the opposing portion of the side member, so that the spacer can be positioned relative to the side member using the wall portion as a reference. This makes it possible to prevent the position of the spacer from shifting relative to the side member.

The wall portion may also be disposed at an end of the spacer in the third direction.

By this, the wall portion (wall portion shaped to follow the opposing portion of the side member) facing the first protrusion of the spacer is disposed at the end of the spacer, so that the spacer can be positioned relative to the side member using the end of the spacer as a reference. This improves the positioning accuracy of the end side of the spacer. Therefore, for example, by disposing the electrode terminal of the energy storage element at the end side of the spacer, the positioning accuracy of the electrode terminal of the energy storage element can be improved, and poor joining can be suppressed when joining the electrode terminal and the bus bar.

The spacer may further have a second protrusion disposed at a position sandwiching the opposing portion between the first protrusion and the spacer, and protruding toward the opposing portion in a direction opposite to the direction in which the first protrusion protrudes in the third direction.

With this, the spacer has a second protrusion that protrudes toward the facing portion of the side member at a position where the spacer and the first protrusion sandwich the facing portion, so that the facing portion can be sandwiched between the first protrusion and the second protrusion. This makes it possible to further prevent a gap from being formed between the spacer and the facing portion, and therefore to further prevent the position of the spacer from shifting relative to the side member.

The spacer may further include a third protrusion that protrudes toward the opposing portion in the second direction.

In this way, since the spacer has a third protrusion that protrudes toward the opposing portion of the side member in the second direction, it is possible to prevent a gap from being formed between the spacer and the opposing portion in the second direction as well. This makes it possible to further prevent the position of the spacer from being shifted relative to the side member.

The present invention can be realized not only as an electricity storage device, but also as a combination of a spacer and a side member, or as a spacer itself.

The electric storage device of the present invention can prevent the spacer from shifting in position relative to the side member.

1 is a perspective view showing an external appearance of a power storage device according to an embodiment; 2 is a perspective view showing the inside of an exterior body with a main body and a lid separated in an energy storage device according to an embodiment; FIG. 2 is an exploded perspective view showing inner components of an exterior body of the energy storage device according to the embodiment; FIG. FIG. 2 is an exploded perspective view illustrating the components of the electricity storage unit according to the embodiment. FIG. 2 is an exploded perspective view showing each component of the energy storage element according to the embodiment. FIG. 2 is a perspective view showing a configuration of a spacer according to an embodiment. 4 is a top view showing a configuration of a side wall portion of the spacer according to the embodiment. FIG. FIG. 2 is a perspective view showing a configuration of a side member according to the embodiment. 5 is a top view showing a positional relationship between a spacer and a side member according to the embodiment. FIG. 5 is a top view showing a positional relationship between a side wall portion and a side member of the spacer according to the embodiment. FIG. 2 is a cross-sectional view showing the positional relationship between an energy storage element, a spacer, an end member, a side member, and an exterior body in the embodiment. FIG.

The following describes an energy storage device according to an embodiment of the present invention (including its variations) with reference to the drawings. Note that the embodiments described below are all comprehensive or specific examples. The numerical values, shapes, materials, components, component placement and connection forms, 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. Furthermore, the dimensions and other details are not strictly shown in each figure. Furthermore, the same reference numerals are used in each figure to identify identical or similar components.

In the following description and drawings, the X-axis direction is defined as the longitudinal direction of the exterior body of the energy storage device, the arrangement direction of the energy storage unit and the electrical equipment unit, the arrangement direction of the multiple side members, the extension direction of the end members, the opposing direction of the short side surfaces of the container of the energy storage element, or the arrangement direction of a pair of electrode terminals in one energy storage element. The Y-axis direction is defined as the arrangement direction of the energy storage element and the bus bar or bus bar frame, or the arrangement direction of the main body and the lid of the container of the energy storage element. The Z-axis direction is defined as 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 end members, the arrangement direction of the energy storage element, the spacer and the end member, 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, or the up-down direction. These X-axis, Y-axis and Z-axis directions intersect each other (orthogonal in this embodiment). Note that, depending on the usage mode, it is possible that the Z-axis direction is not the up-down direction, but for convenience of explanation, the Z-axis direction will be described as the up-down direction below.

In the following description, for example, the positive X-axis direction refers to the direction of the X-axis arrow, and the negative X-axis direction refers to the opposite direction to the positive X-axis direction. The same applies to the Y-axis and Z-axis directions. In the following, the Z-axis direction may also be called the first direction or arrangement direction, the X-axis direction may also be called the second direction, and the Y-axis direction may also be called the third direction. Furthermore, expressions indicating relative directions or attitudes, such as parallel and perpendicular, may also include cases where the directions or attitudes are not strictly those. For example, saying 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, that is, there is a difference of, for example, about a few percent.

(Embodiment)
[1 General Description of Power Storage Device 10]
First, a schematic configuration of the energy storage device 10 according to the present embodiment will be described. Fig. 1 is a perspective view showing the external appearance of the energy storage device 10 according to the present embodiment. Fig. 2 is a perspective view showing the inside of the exterior body 100 in the energy storage device 10 according to the present 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 energy storage device 10 according to the present embodiment.

The power storage device 10 is a device that can charge electricity from the outside and discharge electricity to the outside, and in this embodiment, has a substantially rectangular parallelepiped shape. For example, the power storage device 10 is a battery module (battery pack) used for power storage or power source applications. Specifically, the power storage device 10 is used as a battery for driving or starting the engine of a moving body such as an automobile, motorcycle, watercraft, ship, snowmobile, agricultural machinery, construction machinery, or railroad vehicle for electric railway. 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 railroad vehicles for electric railways 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 for power generation.

As shown in Figures 1 to 3, the energy storage device 10 includes an exterior body 100, and an energy storage unit 200 and an electric equipment unit 300 housed in the exterior body 100. In addition to the above components, the energy storage device 10 may also include an exhaust section for exhausting gas discharged from the energy storage unit 200 to the outside of the exterior body 100, and a connector connected to the electric equipment unit 300 by an electric wire or the like for transmitting signals to the outside.

The exterior body 100 is a box-shaped (approximately rectangular parallelepiped) container (module case) that constitutes the exterior body of the energy storage device 10. In other words, the exterior body 100 is arranged outside the energy storage unit 200 and the electric equipment unit 300, and fixes the energy storage unit 200 and the electric equipment unit 300 at a predetermined position to protect them from impacts and the like. The exterior body 100 is formed of, for example, 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), polyether sulfone (PES), ABS resin, or a composite material thereof, or a metal with an insulating coating. The exterior body 100 thereby prevents the power storage unit 200 and the electrical equipment unit 300 from coming into contact with external metal members, etc. Note that the exterior body 100 may be formed of a conductive member such as a metal, as long as the electrical insulation of the power storage unit 200 and the electrical equipment unit 300 is maintained.

The exterior body 100 has an exterior body main body 110 that constitutes the main body of the exterior body 100, and an exterior body lid body 120 that constitutes the lid body of the exterior body 100. The exterior body main body 110 is a bottomed rectangular cylindrical housing (chassis) with an opening formed on the positive side of the Z axis, and houses the energy storage unit 200 and the electric equipment unit 300. The exterior body main body 110 has a bottom wall portion 111, four side wall portions 112, and multiple protrusions 113.

The bottom wall 111 is disposed on the negative Z-axis side of the exterior body 110, and is a flat, rectangular wall that forms the bottom surface of the exterior body 110. A rib 111a is formed on the positive Z-axis surface of the bottom wall 111. The rib 111a is a convex portion that protrudes in the positive Z-axis direction from the positive Z-axis surface of the bottom wall 111, and a plurality of ribs 111a extending in the X-axis and Y-axis directions are formed over almost the entire surface of the positive Z-axis surface of the bottom wall 111. The four side walls 112 are disposed on both sides of the X-axis and Y-axis of the exterior body 110, and are four flat, rectangular walls that form two short sides on both sides of the X-axis and two long sides on both sides of the Y-axis of the exterior body 110.

The protrusions 113 are members that penetrate the bottom wall 111 in the Z-axis direction and protrude in the Z-axis positive direction from the surface of the bottom wall 111 in the Z-axis positive direction (see FIG. 11). In this embodiment, two protrusions 113 aligned in the Y-axis direction are disposed at the center in the X-axis direction and the end in the X-axis positive direction of the bottom wall 111. Each protrusion 113 is attached to the end member 230 and the side member 240 by inserting the portion protruding in the Z-axis positive direction from the bottom wall 111 into the openings (openings 230b and 244 described below) formed in the end member 230 and the side member 240.

For example, the protrusion 113 is a bolt such as a sealing bolt, and the male thread of the bolt is arranged to protrude in the Z-axis positive direction from the surface of the bottom wall 111 in the Z-axis positive direction beyond the rib 111a. The male thread of the protrusion 113 is screwed into a female thread formed in at least one of the openings 230b and 244, thereby attaching the bottom wall 111 to the end member 230 and the side member 240. In this embodiment, the male thread of the protrusion 113 passes through the opening 230b of the end member 230 and is screwed into the female thread of the opening 244 of the side member 240, thereby fixing the bottom wall 111 to the side member 240 with the end member 230 sandwiched between them.

In this way, one of the exterior body 100 and the side member 240 (in this embodiment, the exterior body 100) has a protrusion (protrusion 113) that protrudes toward the other (in this embodiment, the side member 240), and the other has an opening (opening 244) into which the protrusion is inserted. Then, the side member 240 is fixed to the exterior body 100 by fixing the protrusion (protrusion 113) to the other (side member 240) within the opening (opening 244).

The exterior body cover 120 is a flat rectangular member that closes the opening of the exterior body main body 110. The exterior body cover 120 is joined to the exterior body main 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 both ends of the exterior body cover 120 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 the pair of external terminals 130. The external terminals 130 are formed of a conductive member made of metal, such as aluminum, an aluminum alloy, copper, or a copper alloy.

The energy storage unit 200 has a shape that is flat in the Z-axis direction and elongated in the X-axis direction, with multiple energy storage elements 210 laid horizontally (turned over) and arranged (stacked) in the Z-axis direction and aligned in the X-axis direction. Specifically, the energy storage unit 200 has a configuration in which multiple energy storage elements 210 aligned in the Z-axis direction and the X-axis direction are sandwiched in the Z-axis direction and the X-axis direction by a pair of end members 230 and multiple (three) side members 240 together with a spacer 220. A more detailed explanation of the configuration of the energy storage unit 200 will be given later.

The electric equipment unit 300 has an electric equipment 310, an attachment member 320, and a busbar unit 330. The electric equipment 310 is an equipment that can monitor the state of the energy storage element 210 of the energy storage unit 200 and control the energy storage element 210. In this embodiment, the electric equipment 310 is a flat rectangular member that is arranged and attached in the positive direction of the X-axis of the energy storage unit 200. The electric equipment 310 has electric components such as a circuit board, a shunt resistor, and a connector that monitor the charging and discharging state of the energy storage element 210 and control the charging and discharging of the energy storage element 210. The electric equipment 310 has a configuration in which these electric components are housed in an insulating cover member.

The mounting member 320 is a flat plate-shaped member that mounts the electrical device 310 to the energy storage unit 200. The mounting member 320 is formed of, for example, any electrically insulating resin material that can be used for the exterior body 100 described above. The mounting member 320 is disposed between the energy storage unit 200 and the electrical device 310, and is attached to the energy storage unit 200 while the electrical device 310 is attached to it. In this embodiment, the mounting member 320 is attached to the side surface of the energy storage unit 200 in the positive direction of the X axis, so that the electrical device 310 is attached to the side surface of the energy storage unit 200 in the positive direction of the X axis in an upright position (a position parallel to the YZ plane).

Specifically, the mounting member 320 is attached to the end member 230 and the side member 240 of the energy storage unit 200, which will be described later. More specifically, the mounting member 320 has four protrusions 321 at both ends in the Z-axis direction and both ends in the Y-axis direction. The protrusions 321 have portions that protrude in the Z-axis direction toward the end member 230, and are attached to the end member 230 and the side member 240 by inserting these portions into openings (openings 230c and 244, which will be described later) formed in the end member 230 and the side member 240. For example, the protrusions 321 are bolts, and the male threads of the bolts are screwed into the female threads formed in at least one of the openings 230c and 244, thereby attaching the mounting member 320 to the end member 230 and the side member 240.

The busbar unit 330 has a busbar and a relay, and electrically connects the energy storage unit 200 and the electric device 310, electrically connects the electric device 310 and the external terminal 130, and electrically connects the energy storage unit 200 and the external terminal 130. The busbar is a plate-shaped member that connects the busbar 250 (described later) of the energy storage unit 200 to the electric device 310, connects the electric device 310 and the external terminal 130, connects the busbar 250 to the relay, and connects the relay to the external terminal 130. The busbar is formed of, for example, a conductive member made of a 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.

[2. Description of the Configuration of the Energy Storage Unit 200]
Next, the configuration of the energy storage unit 200 will be described in detail with reference to Fig. 4 in addition to Fig. 3. Fig. 4 is an exploded perspective view showing the components of the energy storage unit 200 according to the present embodiment. Note that in Fig. 4, the bus bar 250 and the bus bar frame 251 of the energy storage unit 200 are omitted.

As shown in Figures 3 and 4, the energy storage unit 200 has a plurality of energy storage elements 210 (211, 212), a plurality of spacers 220 (221, 222), a pair of end members 230 (231, 232), three side members 240, a plurality of bus bars 250, and a bus bar frame 251.

The storage element 210 is a secondary battery (single cell) capable of charging and discharging electricity, and more specifically, a non-aqueous electrolyte secondary battery such as a lithium ion secondary battery. The storage element 210 has a flat rectangular parallelepiped shape (rectangular shape). In this embodiment, eight storage elements 210 are arranged in the Z-axis direction and the X-axis direction in a horizontally placed (lying down) state (with the long side of the storage element 210 facing the Z-axis direction). Specifically, the four storage elements 211 on the negative side of the X-axis are arranged (stacked) in the Z-axis direction (arrangement direction), and the four storage elements 212 on the positive side of the X-axis are arranged (stacked) in the Z-axis direction (arrangement direction). The four storage elements 211 and the four storage elements 212 are arranged side by side in the X-axis direction. A detailed description of the configuration of the storage elements 210 (211, 212) will be described later.

The number of the storage elements 210 is not particularly limited, and any number of the storage elements 210 may be stacked (flat) in the Z-axis direction, or any number of the storage elements 210 may be arranged in the X-axis direction. In other words, the storage unit 200 may have only one storage element 210. The shape of the storage element 210 is not limited to the above-mentioned square shape, and may be other shapes such as a polygonal column shape, a cylindrical shape, an elliptical column shape, or an oblong column shape. The storage element 210 is not limited to a non-aqueous electrolyte secondary battery, and may be a secondary battery other than a non-aqueous electrolyte secondary battery, or may be a capacitor. The 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 storage element 210 may be a battery using a solid electrolyte. The storage element 210 may be a pouch-type storage element.

The spacer 220 (221, 222) is a flat, rectangular member that is arranged (arranged) alongside the energy storage element 210 in the Z-axis direction (first direction, arrangement direction) and electrically insulates the energy storage element 210 from other components. The spacer 220 (221, 222) is formed, for example, from any electrically insulating resin material that can be used for the exterior body 100 described above.

Specifically, the spacers 221 are intermediate spacers (inter-cell spacers) arranged adjacent to the storage elements 210 in the Z-axis direction. That is, the spacers 221 are arranged between two adjacent storage elements 210 (between the two storage elements 211 and between the two storage elements 212) and electrically insulate the two storage elements 210. In this embodiment, three spacers 221 are arranged corresponding to the four storage elements 211, but when the number of storage elements 211 is other than four, the number of spacers 221 is appropriately changed according to the number of storage elements 211. The same applies to the storage elements 212.

The spacers 222 are end spacers that are arranged at the ends of the spacers 220 in the Z-axis direction (first direction, arrangement direction), and are arranged adjacent to the end storage elements 210 in the Z-axis direction. The spacers 222 are arranged between the end storage elements 210 (end storage elements 211 and 212) and the end members 230 (231, 232), and electrically insulate the end storage elements 210 from the end members 230 (231, 232). In other words, two spacers 222 are arranged on both sides of the four storage elements 211 in the Z-axis direction, and two spacers 222 are arranged on both sides of the four storage elements 212 in the Z-axis direction.

The spacer 220 (221, 222) has walls on both sides in the X-axis direction and on both sides in the Y-axis direction, and is electrically insulated from other components arranged on both sides of the energy storage element 210 in the X-axis direction and on both sides in the Y-axis direction. For example, the spacer 220 (221, 222) has walls arranged between the energy storage element 210 and the side member 240, and electrically insulates the energy storage element 210 from the side member 240. A detailed description of the configuration of the spacer 220 (221) will be given later.

The end member 230 and the side member 240 are members (restraining members) that compress (restrain) the energy storage element 210 from the outside in the Z-axis direction. In other words, the end member 230 and the side member 240 sandwich the multiple energy storage elements 210 and the multiple spacers 220 from both sides in the Z-axis direction, thereby compressing (restraining) each of the energy storage elements 210 and the multiple spacers 220 from both sides in the Z-axis direction. The end member 230 and the side member 240 are formed of metal members such as stainless steel, aluminum, aluminum alloy, iron, plated steel sheet, etc., but may also be formed of insulating members such as highly rigid resin.

The end members 230 (231, 232) are arranged in a position sandwiching the multiple storage elements 210 (211 and 212) and the multiple spacers 220 (221 and 222) in the Z-axis direction, and are a pair of flat plate-shaped members (end plates) that sandwich them in the Z-axis direction. As a result, the pair of end members 230 collectively restrain the multiple storage elements 210 and the multiple spacers 220 in the Z-axis direction (collectively apply a restraining force in the Z-axis direction to the multiple storage elements 210 and the multiple spacers 220). The end member 231 is the end member 230 on the negative side of the Z-axis of the pair of end members 230, and the end member 232 is the end member 230 on the positive side of the Z-axis. The end members 230 (231, 232) may be block-shaped or rod-shaped members instead of flat plate-shaped members.

The side member 240 is a flat member (side plate) arranged adjacent to the spacer 220 in the X-axis direction (second direction intersecting the first direction) and facing the spacer 220. Both ends of the side member 240 are attached to a pair of end members 230, and by connecting the pair of end members 230, the side member 240 restrains the multiple storage elements 210 and the multiple spacers 220. In other words, the side member 240 is arranged extending in the Z-axis direction so as to straddle the multiple storage elements 210 and the multiple spacers 220, and applies a restraining force to the multiple storage elements 210, etc. in the arrangement direction (Z-axis direction). Note that the side member 240 may be a block-shaped or rod-shaped member rather than a flat member.

In this embodiment, three side members 240 are arranged in the negative X-axis direction of the multiple storage elements 211, between the multiple storage elements 211 and the multiple storage elements 212, and in the positive X-axis direction of the multiple storage elements 212. In other words, in the X-axis direction (second direction), two sets of storage elements 210 and spacers 220 are arranged at positions sandwiching the central side member 240, and two side members 240 are arranged at positions sandwiching the two sets of storage elements 210 and spacers 220. These three side members 240 are attached to both ends in the X-axis direction and the center of a pair of end members 230 at both ends in the Z-axis direction. As a result, the end members 230 and the side members 240 sandwich and restrain the multiple storage elements 210 and the multiple spacers 220 from both sides in the X-axis direction and both sides in the Z-axis direction.

Specifically, the end members 230 (231, 232) have protrusions 230a (231a, 232a), and are connected (joined) to the respective side members 240 by the protrusions 230a. In this embodiment, three protrusions 230a aligned in the Y-axis direction are arranged at the center and both ends of the end member 230 in the X-axis direction. The protrusions 230a have portions that protrude in the Z-axis direction from the surface of the end member 230 facing the side member 240 toward the side member 240, and are attached to the side member 240 by being inserted into openings 243 formed in the side member 240.

For example, the protrusion 230a is a bolt, and the male thread of the bolt is screwed into the female thread formed in the opening 243, thereby attaching the end member 230 to the side member 240. Alternatively, the protrusion 230a is a self-tapping bolt (tapping bolt), and the end member 230 is attached to the side member 240 by screwing it into the opening 243 while forming a female thread. The arrangement position and number of the protrusions 230a are not particularly limited. In addition, the method of connecting the end member 230 and the side member 240 may be other methods, such as welding, crimping, adhesion, or welding. A detailed description of the configuration of the side member 240 will be given later.

In addition, the end members 230 (231, 232) have the above-mentioned two openings 230b (231b, 232b) arranged between the three protrusions 230a (231a, 232a) lined up in the Y-axis direction at the center in the X-axis direction and at the end in the positive X-axis direction. In other words, the three protrusions 230a (231a, 232a) and the two openings 230b (231b, 232b) are arranged alternately in the Y-axis direction. The openings 230b (231b, 232b) are circular through-holes that penetrate the end members 230 (231, 232) in the Z-axis direction. At the end of the end member 230 (231, 232) in the negative X-axis direction, the above-mentioned two openings 230c (231c, 232c) are arranged between the three protrusions 230a (231a, 232a) arranged in the Y-axis direction. In other words, the three protrusions 230a (231a, 232a) and the two openings 230c (231c, 232c) are arranged alternately in the Y-axis direction. The openings 230c (231c, 232c) are circular through-holes that penetrate the end member 230 (231, 232) in the Z-axis direction.

The bus bar 250 is a flat member connected to the energy storage element 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. That is, the bus bar 250 connects the electrode terminals 210b of the multiple energy storage elements 210 to each other, and connects the electrode terminals 210b of the end energy storage elements 210 to the bus bar unit 330. In this 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 bolt fastening or the like. The bus bar 250 is formed of, for example, 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 this embodiment, the bus bar 250 connects two storage elements 210 in parallel to form four sets of storage element groups, and connects the four sets of storage element groups in series, but the bus bar 250 may also connect all eight storage elements 210 in series, or may have another configuration.

The busbar frame 251 is a flat rectangular insulating member that can electrically insulate the busbar 250 from other members and regulate the position of the busbar 250. The busbar frame 251 is formed of, for example, any electrically insulating resin material that can be used for the exterior body 100 described above. The busbar frame 251 is arranged in the negative Y-axis direction of the multiple storage elements 210 and is positioned relative to the multiple storage elements 210. The busbar 250 is also positioned on the busbar frame 251. As a result, the busbar 250 is positioned relative to the multiple storage elements 210 and joined to the electrode terminals 210b of the multiple storage elements 210.

[3. Description of the Configuration of Energy Storage Element 210]
Next, the configuration of the energy storage element 210 will be described in detail. Fig. 5 is an exploded perspective view showing each component of the energy storage element 210 according to the present embodiment. Specifically, Fig. 5 shows an exploded view of each part of the energy storage element 210 shown in Fig. 4 in a vertically placed (standing) state. Note that since all eight energy storage elements 210 (four energy storage elements 211 and four energy storage elements 212) have the same configuration, the configuration of one energy storage element 210 will be described below.

As shown in FIG. 5, the energy storage element 210 includes a container 210a, a pair of electrode terminals 210b (positive and negative), and a pair of gaskets 210c (positive and negative). The container 210a also contains a pair of gaskets 210d (positive and negative), a pair of collectors 210e (positive and negative), and an electrode body 210f. An electrolyte (non-aqueous electrolyte) is enclosed inside the container 210a, but is not shown. There is no particular limit to the type of electrolyte as long as it does not impair the performance of the energy storage element 210, and various electrolytes can be selected. In addition to the above components, a spacer disposed on the side or below the electrode body 210f, an insulating film that encases the electrode body 210f, or an insulating sheet that covers the outer surface of the container 210a may be disposed.

The container 210a is a rectangular parallelepiped (angular or box-shaped) case having a container body 210a1 with an opening and a container lid 210a2 that closes the opening of the container body 210a1. With this configuration, the container 210a is structured so that the inside can be sealed by welding the container body 210a1 and the container lid 210a2 together after the electrode body 210f and other components are housed inside the container body 210a1. The materials of the container body 210a1 and the container lid 210a2 are not particularly limited, but are preferably weldable metals such as stainless steel, aluminum, aluminum alloy, iron, and plated steel sheet.

The container body 210a1 is a rectangular cylindrical member with a bottom that constitutes the main body of the container 210a, and has an opening on the negative Y-axis side. In other words, the container body 210a1 has a pair of rectangular, planar (flat) long sides on both sides in the Z-axis direction, a pair of rectangular, planar (flat) short sides on both sides in the X-axis direction, and a rectangular, planar (flat) bottom surface on the positive Y-axis side. The container lid 210a2 is a rectangular plate-like member that constitutes the lid of the container 210a, and is disposed extending in the X-axis direction on the negative Y-axis side of the container body 210a1.

The electrode body 210f is an electric storage element (power generation element) formed by stacking a positive electrode plate, a negative electrode plate, and a separator. The positive electrode plate is a positive electrode active material layer formed on a positive electrode base layer, which is a current collector foil made of a metal such as aluminum or an aluminum alloy. The negative electrode plate is a negative electrode active material layer formed on a negative electrode base layer, which is a current collector foil made of a metal such as copper or a 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 long as it can absorb and release lithium ions. In this embodiment, the electrode body 210f is a wound type (so-called vertically wound type) electrode body formed by winding the electrode plates (positive electrode plate and negative electrode plate) around a winding axis (a virtual axis parallel to the X-axis direction) extending in the X-axis direction.

Here, the electrode plates (positive and negative plates) of the electrode body 210f are stacked in the Z-axis direction, so the Z-axis direction is also called the stacking direction. In other words, the electrode body 210f is formed by stacking the electrode plates in the stacking direction. The electrode body 210f has a pair of flat parts 210f1 aligned in the Z-axis direction and a pair of curved parts 210f2 aligned in the Y-axis direction by winding the electrode plates, and the stacking direction is the stacking direction of the electrode plates in the flat part 210f1. The flat part 210f1 is a flat part that connects the ends of the pair of curved parts 210f2, and the curved part 210f2 is a part that is curved in a semicircular shape or the like so as to protrude in the Y-axis direction. The stacking direction can also be defined as the direction in which the flat surface of the flat part 210f1 faces, or the direction in which the pair of flat parts 210f1 face each other. For this reason, the multiple storage elements 211 arranged in the arrangement direction (Z-axis direction) can also be said to be arranged in the stacking direction, and the multiple storage elements 212 arranged in the arrangement direction (Z-axis direction) can also be said to be arranged in the stacking direction.

In addition, the electrode body 210f has positive and negative plates wound with a mutual shift in the X-axis direction, so that the positive and negative plates have portions (active material layer non-formed portions) at the ends in the shifted direction where the active material is not formed (coated) and the substrate layer is exposed. In other words, the electrode body 210f has connection portions 210f3 at both ends in the X-axis direction that protrude from the flat portion 210f1 and the curved portion 210f2 on both sides in the X-axis direction, and are connected to the current collector 210e by stacking the active material layer non-formed portions of the positive and negative plates.

The electrode body 210f may be of any type, such as a so-called horizontally wound electrode body formed by winding an electrode plate around a winding axis extending in the Y-axis direction, a laminated (stacked) electrode body formed by stacking multiple flat electrode plates, or a bellows-shaped electrode body in which the electrode plate is folded into a bellows shape. In the case of a horizontally wound electrode body, the flat parts are the curved parts and the flat parts other than the connection parts (tabs) with the current collector, and in the case of a laminated (stacked) and bellows-shaped electrode body, the flat parts are the flat parts other than the connection parts (tabs) with the current collector.

The electrode terminals 210b are terminals (positive and negative terminals) of the storage element 210, and are arranged on the container lid 210a2 so as to protrude in the negative Y-axis direction. The electrode terminals 210b are electrically connected to the positive and negative plates of the electrode body 210f via the current collector 210e. The electrode terminals 210b are formed of a conductive material such as a metal, such as aluminum, an aluminum alloy, copper, or a copper alloy.

The current collector 210e is a conductive member (positive electrode current collector and negative electrode current collector) electrically connected to the electrode terminal 210b and the connection portion 210f3 of the electrode body 210f. The current collector 210e is made of aluminum, an aluminum alloy, copper, a copper alloy, or the like. The gaskets 210c and 210d are flat, electrically insulating sealing members arranged between the container lid portion 210a2 and the electrode terminal 210b and between the current collector 210e and the container lid portion 210a2. The gaskets 210c and 210d are made of, for example, any electrically insulating resin material that can be used for the exterior body 100 described above.

[4. Description of the Configuration of Spacer 221]
Next, the configuration of the spacer 221 will be described in detail. Since all the spacers 221 in the energy storage unit 200 have the same configuration, one spacer 221 will be illustrated and described below. FIG. 6 is a perspective view showing the configuration of the spacer 221 according to this embodiment. Specifically, FIG. 6 shows an enlarged view of the spacer 221 shown in FIG. 4. FIG. 7 is a top view showing the configuration of a side wall portion 280 of the spacer 221 according to this embodiment. Specifically, FIG. 7 shows the configuration of the side wall portion 280a on the X-axis positive direction side of the spacer 221 in FIG. 6 when viewed from the Z-axis positive direction. Note that in FIG. 7, for convenience of explanation, the spacer recesses 285 and 287 are omitted from the illustration.

6 and 7, the spacer 221 has a spacer body 260, a front wall 270, a pair of side walls 280 (280a and 280b), and a rear wall 290. The spacer body 260 is a flat, rectangular part that constitutes the body of the spacer 221, and is arranged at a position facing the energy storage element 210 in the Z-axis direction. Specifically, the spacer body 260 faces the long side of the container 210a of the energy storage element 210, and is arranged between the long sides of the two energy storage elements 210. In this embodiment, the spacer body 260 has a plurality of ribs 261, 262, and 263 extending in the X-axis direction formed on the main surface 260a on both sides in the Z-axis direction, but ribs extending in the Y-axis direction may be formed, or ribs may not be formed.

The front wall portion 270 is a flat wall portion that protrudes from the edge of the spacer body 260 in the negative Y-axis direction on both sides of the Z-axis direction, faces the energy storage element 210 in the Y-axis direction, and is arranged extending in the X-axis direction. Specifically, the front wall portion 270 is arranged so as to cover approximately half of the surface of the container lid portion 210a2 of the energy storage element 210 in the negative Y-axis direction in the Z-axis direction for each energy storage element 210 arranged on both sides of the spacer 221 in the Z-axis direction. More specifically, the front wall portion 270 is arranged so as to cover approximately half of the portion of the energy storage element 210 in the negative Y-axis direction other than the gas exhaust valve and electrode terminal 210b of the container lid portion 210a2 in the Z-axis direction.

The pair of side walls 280 are plate-shaped walls that protrude from both ends of the spacer body 260 in the X-axis direction in both Z-axis directions, face the energy storage element 210 in the X-axis direction, and are arranged to extend in the Y-axis direction. Specifically, the pair of side walls 280 are arranged so as to cover approximately half of the faces (short sides) on both sides of the X-axis direction of the container body 210a1 of the energy storage element 210 for each of the energy storage elements 210 arranged on both sides of the spacer 221 in the Z-axis direction. Hereinafter, the side wall 280 on the positive side of the X-axis direction of the pair of side walls 280 is also referred to as side wall 280a, and the side wall 280 on the negative side of the X-axis direction is also referred to as side wall 280b.

Sidewall portion 280a has spacer protrusions 281-283 and spacer recesses 284-288. Sidewall portion 280b also has spacer protrusions 281-283 and spacer recesses 284-288, similar to sidewall portion 280a. In other words, sidewall portion 280b has a shape that is symmetrical to sidewall portion 280a with respect to the YZ plane that passes through the center of spacer body 260. For this reason, the configuration of sidewall portion 280a will be described in detail below, and the description of the configuration of sidewall portion 280b will be simplified or omitted.

In the side wall portion 280a, the spacer protrusions 281 to 283 are protrusions that protrude in the positive direction of the X-axis, and the spacer recesses 284 to 288 are recesses that are recessed in the negative direction of the X-axis. In other words, the spacer protrusions 281 to 283 protrude toward the side member 240, and the spacer recesses 284 to 288 are recessed in the direction opposite to the side member 240.

The spacer protrusion 281 is disposed at the end of the side wall 280a in the negative Y-axis direction, and is a rectangular column-shaped (in this embodiment, rectangular tube-shaped) protrusion extending in the Z-axis direction protruding in the positive X-axis direction. The spacer protrusion 282 is disposed at the end of the side wall 280a in the positive Y-axis direction, and is a rectangular column-shaped (in this embodiment, rectangular tube-shaped) protrusion extending in the Z-axis direction protruding in the positive X-axis direction. The spacer protrusion 283 is disposed between the spacer protrusions 281 and 282, and is a bulging (U-shaped, inverted C-shaped) protrusion extending in the Z-axis direction protruding in a rectangular shape in the positive X-axis direction when viewed from the Z-axis direction. In this embodiment, four spacer protrusions 283 are disposed between the spacer protrusions 281 and 282.

In this embodiment, the spacer convex portions 281 and 282 have the same amount of protrusion in the positive direction of the X-axis, and are arranged to protrude further in the positive direction of the X-axis than the four spacer convex portions 283. In the Y-axis direction, the spacer convex portion 281 has a larger width than the spacer convex portion 282, and the four spacer convex portions 283 have a larger width than the spacer convex portions 281 and 282. The four spacer convex portions 283 have the same amount of protrusion in the positive direction of the X-axis, and also have the same width in the Y-axis direction.

Spacer recess 284 is disposed between spacer protrusions 281 and 283, and is a generally C-shaped recess that is recessed into a rectangular shape when viewed from the Z-axis direction. Spacer recesses 285 to 287 are disposed between two adjacent spacer protrusions 283, and are generally C-shaped recesses that are recessed into a rectangular shape when viewed from the Z-axis direction. Spacer recess 288 is disposed between spacer protrusions 282 and 283, and is generally C-shaped recess that is recessed into a rectangular shape when viewed from the Z-axis direction. In other words, the five recesses disposed between two adjacent spacer protrusions out of the six spacer protrusions of spacer protrusion 281, four spacer protrusions 283, and spacer protrusion 282 are referred to as spacer recesses 284, 285, 286, 287, and 288, in order from the negative Y-axis direction.

As shown in FIG. 7, the spacer recess 284 has a pair of walls 284d and 284e facing each other in the Y-axis direction, and a wall 284f connecting the walls 284d and 284e. The wall 284d has a first protrusion 284a, and the wall 284f has a third protrusion 284c.

The wall 284d is a wall extending in the Z-axis direction facing the negative Y-axis direction, and the surface facing the negative Y-axis direction has a shape in which the first protrusion 284a protrudes from a flat rectangular plane. The wall 284d is also a wall constituting the spacer protrusion 283. The wall 284e is a wall extending in the Z-axis direction facing the positive Y-axis direction, and the surface facing the positive Y-axis direction is a flat rectangular plane. Since the wall 284e is also a wall constituting the spacer protrusion 281 at the end of the spacer 221 in the Y-axis direction, it can be said that the wall 284e is disposed at the end of the spacer 221 in the Y-axis direction (a third direction intersecting the first and second directions). The wall 284f is a wall extending in the Z-axis direction facing the positive X-axis direction, and the surface facing the positive X-axis direction has a shape in which the third protrusion 284c protrudes from a flat rectangular plane.

The first protrusion 284a is a rib that protrudes from the center of the wall 284d in the X-axis direction in the negative Y-axis direction, and is arranged to extend from one end of the wall 284d to the other end in the Z-axis direction. In this embodiment, the first protrusion 284a is a trapezoidal protrusion as viewed from the X-axis direction, with the length in the Z-axis direction becoming shorter as it approaches the negative Y-axis direction. The arrangement position and shape of the first protrusion 284a are not particularly limited, and for example, the first protrusion 284a may be arranged at the end of the wall 284d in the X-axis direction, or at the end or center in the Z-axis direction, or may have a shape other than a trapezoidal shape as viewed from the X-axis direction. The number of first protrusions 284a is also not particularly limited, and multiple first protrusions 284a may be arranged side by side in the X-axis or Z-axis directions.

The third protrusion 284c is a rib that protrudes from the wall portion 284f in the positive direction of the X-axis, and is arranged extending from one end of the wall portion 284f to the other end in the Z-axis direction. In this embodiment, the third protrusion 284c is a trapezoidal protrusion as viewed from the Y-axis direction, in which the length in the Z-axis direction becomes shorter as it approaches the positive direction of the X-axis, and two third protrusions 284c are arranged side by side in the Y-axis direction. The arrangement position and shape of the third protrusion 284c are not particularly limited, and for example, the third protrusion 284c may be arranged in the center of the wall portion 284d in the Y-axis direction, or in the end or center in the Z-axis direction, or may have a shape other than a trapezoidal shape as viewed from the Y-axis direction. The number of third protrusions 284c is also not particularly limited, and may be one or three or more, or multiple third protrusions 284c may be arranged side by side in the Z-axis direction.

The spacer recess 286 has a pair of walls 286d and 286e facing each other in the Y-axis direction, and a wall 286f connecting the walls 286d and 286e. The wall 286d has a first protrusion 286a, the wall 286e has a second protrusion 286b, and the wall 286f has a third protrusion 286c. The walls 286d and 286f have the same configuration as the walls 284d and 284f of the spacer recess 284. The wall 286e is a wall extending in the Z-axis direction facing the Y-axis positive direction, and the surface facing the Y-axis positive direction has a shape in which the second protrusion 286b protrudes from a flat rectangular plane. The wall 286e is also a wall that constitutes the spacer protrusion 283.

The first protrusion 286a and the third protrusion 286c have the same configuration as the first protrusion 284a and the third protrusion 284c of the spacer recess 284. The second protrusion 286b is a rib that protrudes in the positive Y-axis direction from the center of the wall portion 286e in the X-axis direction, and is arranged extending from one end to the other end of the wall portion 286e in the Z-axis direction. In this embodiment, the second protrusion 286b is a trapezoidal protrusion as viewed from the X-axis direction, the length of which becomes shorter in the Z-axis direction as it approaches the positive Y-axis direction. The arrangement position and shape of the second protrusion 286b are not particularly limited, and for example, the second protrusion 286b may be arranged at the end of the wall portion 286e in the X-axis direction, or at the end or center in the Z-axis direction, or may have a shape other than a trapezoidal shape as viewed from the X-axis direction. The number of second protrusions 286b is also not particularly limited, and multiple second protrusions 286b may be arranged side by side in the X-axis direction or the Z-axis direction.

The spacer recess 288 has a pair of walls 288d and 288e facing each other in the Y-axis direction, and a wall 288f connecting the walls 288d and 288e. The wall 288d has a first protrusion 288a, the wall 288e has a second protrusion 288b, and the wall 288f has a third protrusion 288c. The walls 288e and 288f have the same configuration as the walls 286e and 286f of the spacer recess 286. The wall 288d is a wall extending in the Z-axis direction facing the negative Y-axis direction, and the surface facing the negative Y-axis direction has a shape in which the first protrusion 288a protrudes from a flat rectangular plane. The wall 288d is also a wall constituting the spacer protrusion 282 at the end of the spacer 221 in the Y-axis direction, so it can be said that the wall 288d is disposed at the end of the spacer 221 in the Y-axis direction (third direction).

The first protrusion 288a is a rib that protrudes from the wall portion 288d in the negative Y-axis direction, and is arranged extending from one end of the wall portion 288d to the other end in the Z-axis direction. In this embodiment, the first protrusion 288a is a trapezoidal protrusion as viewed from the X-axis direction, the length of which becomes shorter in the Z-axis direction as it approaches the negative Y-axis direction, and two first protrusions 288a are arranged side by side in the X-axis direction. The arrangement position and shape of the first protrusion 288a are not particularly limited, and for example, the first protrusion 288a may be arranged in the center of the wall portion 288d in the X-axis direction, or in the end or center in the Z-axis direction, or may have a shape other than a trapezoidal shape as viewed from the X-axis direction. The number of first protrusions 288a is also not particularly limited, and may be one or three or more, or multiple first protrusions 288a may be arranged side by side in the Z-axis direction.

In this way, the first protrusions 284a, 286a, 288a protrude in the Y-axis direction (third direction), and the walls 284e, 286e, 288e are disposed opposite the first protrusions 284a, 286a, 288a in the Y-axis direction (third direction). The second protrusions 286b, 288b protrude in the Y-axis direction, and the walls 286d, 288d are disposed opposite the second protrusions 286b, 288b in the Y-axis direction. In this embodiment, the first protrusions 284a, 286a, and 288a, the second protrusions 286b and 288b, and the third protrusions 284c, 286c, and 288c all have the same shape.

Here, the width B between the pair of walls 286d and 286e of the spacer recess 286 is greater than the width A between the pair of walls 284d and 284e of the spacer recess 284, and the width C between the pair of walls 288d and 288e of the spacer recess 288 is greater than the width B. The spacer recess 285 has a similar configuration to the spacer recess 286, but the width of the pair of walls facing each other in the Y-axis direction of the spacer recess 285 is greater than the width A and smaller than the width B. The spacer recess 287 has a similar configuration to the spacer recess 286, but the width of the pair of walls facing each other in the Y-axis direction of the spacer recess 287 is greater than the width B and smaller than the width C.

In other words, at least two of the spacer recesses 284-288 (all of the spacer recesses in this embodiment) have different widths in the Y-axis direction (third direction) between a pair of wall portions facing each other in the Y-axis direction (third direction). Specifically, the width in the Y-axis direction (third direction) between the pair of wall portions of the spacer recesses 284-288 increases from the spacer recess at one end in the Y-axis direction (third direction) to the spacer recess at the other end. In this embodiment, the width between the pair of wall portions gradually increases from the spacer recess 284 at the end in the negative Y-axis direction to the spacer recess 288 at the end in the positive Y-axis direction.

The rear wall portion 290 is a flat wall portion that protrudes from the edge of the spacer body 260 in the positive Y-axis direction on both sides in the Z-axis direction, faces the energy storage element 210 in the Y-axis direction, and is arranged extending in the X-axis direction. Specifically, the rear wall portion 290 is arranged so as to cover approximately half of the surface (bottom surface) in the positive Y-axis direction of the container body 210a1 of the energy storage element 210 in the Z-axis direction for each of the energy storage elements 210 arranged on both sides of the spacer 221 in the Z-axis direction.

The configuration of the spacer 221 has been described above, but the spacer 222 has the same configuration as the spacer 221. In other words, all the spacers 222 have walls with the same configuration as the front wall 270, the pair of side wall portions 280 (280a and 280b), and half of the rear wall portion 290 in the Z-axis direction of the spacer 221.

[5. Description of the Configuration of Side Member 240]
Next, the configuration of the side member 240 will be described in detail. Since all of the side members 240 of the energy storage unit 200 have the same configuration, the following description will be given by illustrating one side member 240. Fig. 8 is a perspective view showing the configuration of the side member 240 according to the present embodiment. Specifically, Fig. 8 shows an enlarged view of the side member 240 shown in Fig. 4.

As shown in FIG. 8, the side member 240 has a side protrusion 241 in which the above-mentioned openings 243 and 244 are formed, and a side recess 242. In this embodiment, five side protrusions 241 and four side recesses 242 are arranged alternately in the Y-axis direction.

The side protrusion 241 is a protruding portion of the side member 240 that protrudes in the X-axis direction and extends in the Z-axis direction. In this embodiment, the side protrusion 241 is a rectangular columnar (rectangular parallelepiped) portion that protrudes in a rectangular shape on both sides of the side member 240 in the X-axis direction and extends from one end to the other end of the side member 240 in the Z-axis direction. Here, the side protrusion 241 in which the opening 243 is formed is called the side protrusion 241a, and the side protrusion 241 in which the opening 244 is formed is called the side protrusion 241b. In other words, three side protrusions 241a and two side protrusions 241b are arranged alternately in the Y-axis direction. Two openings 243 extending in the Z-axis direction are formed at both ends of the side protrusion 241a in the Z-axis direction, and two openings 244 extending in the Z-axis direction are formed at both ends of the side protrusion 241b in the Z-axis direction.

As described above, the side protrusion 241a is fixed to the pair of end members 230 in the Z-axis direction by inserting the protrusions 230a (231a, 232a) of the pair of end members 230 (231, 232) into the openings 243 on both sides in the Z-axis direction. The side protrusion 241b is fixed to the exterior body 100 in the Z-axis direction by inserting the protrusion 113 of the exterior body main body 110 of the exterior body 100 into the opening 244 in the negative Z-axis direction. Note that for the side member 240 on the negative X-axis side, the side protrusion 241b is fixed to the electric equipment unit 300 in the Z-axis direction by inserting the protrusion 321 of the mounting member 320 of the electric equipment unit 300 into the openings 244 on both sides in the Z-axis direction.

In this way, the side protrusions 241 are fixed to other members different from the spacer 221 and the side member 240. That is, at least two side protrusions 241 are fixed to at least two other members different from each other. Specifically, the side protrusions 241 are fixed to the end member 230, the exterior body 100, and the electric equipment unit 300. The side member 240 is fixed to the pair of end members 230 at a position (position of the side protrusion 241a) adjacent to the protrusion 113 of the exterior body 100 and the opening 244 of the side protrusion 241b. Furthermore, the side member 240 is fixed to the pair of end members 230 and the electric equipment unit 300 in the same direction (Z-axis direction) as the protruding direction of the protrusion 113 (fixing direction with the exterior body 100).

The side recess 242 is a portion of the side member 240 that is recessed in the X-axis direction and extends in the Z-axis direction, and is disposed adjacent to the side protrusions 241 (241a, 241b). In this embodiment, the side recess 242 is a flat, rectangular (cuboid-shaped) portion that is recessed in a rectangular shape from both sides of the side member 240 in the X-axis direction and extends from one end of the side member 240 in the Z-axis direction to the other end.

The side convex portion 241b is an example of a first side portion where the protrusion 113 or the opening 244 of the exterior body 100 is arranged, and the side concave portion 242 is an example of a second side portion adjacent to the first side portion. In other words, the first side portion of the side member 240 is thicker in the arrangement direction (X-axis direction) of the energy storage element 210 and the side member 240 than the second side portion.

[6. Description of Positional Relationship between Spacer 221, Side Member 240, and Exterior Body 100]
Next, the positional relationship between the spacer 221, the side member 240, and the exterior body 100 will be described in detail. FIG. 9 is a top view showing the positional relationship between the spacer 221 and the side member 240 according to this embodiment. Specifically, FIG. 9 shows the configuration when the spacer 221, the side member 240, and the energy storage element 210 are assembled and viewed from the Z-axis positive direction. FIG. 10 is a top view showing the positional relationship between the side wall portion 280 of the spacer 221 and the side member 240 according to this embodiment. Specifically, FIG. 10 shows the configuration when the side wall portion 280a on the X-axis positive direction side of the spacer 221 in FIG. 9 and the side member 240 are viewed from the Z-axis positive direction. Note that FIG. 10 is a view corresponding to FIG. 7. FIG. 11 is a cross-sectional view showing the positional relationship between the energy storage element 210, the spacer 220, the end member 230, the side member 240, and the exterior body 100 according to this embodiment. Specifically, FIG. 11 shows a cross section of the power storage device 10 taken along a plane that passes through the protruding portion 113 of the exterior body 100 and is parallel to the XZ plane.

9 and 10, the spacer protrusions 283 of the side wall 280 of the spacer 221 are inserted into the side recesses 242 of the side member 240. The side protrusions 241 of the side member 240 are inserted into the spacer recesses 284 to 288 of the side wall 280 of the spacer 221. Specifically, the side protrusions 241 are sandwiched between a pair of walls 284d and 284e of the spacer recess 284, between a pair of walls 286d and 286e of the spacer recess 286, and between a pair of walls 288d and 288e of the spacer recess 288, etc., and are disposed in a state where they are sandwiched between these pairs of walls. The side protrusions 241 and the spacer recesses 284 to 288 each abut in the Y-axis direction, thereby restricting the movement of the spacer 221 in the Y-axis direction relative to the side member 240.

That is, one of the spacer 221 and the side member 240 has a plurality of convex portions protruding toward the other, and the other has a plurality of concave portions into which the plurality of convex portions are inserted. Each of the plurality of concave portions has a pair of walls that sandwich the plurality of convex portions in the Y-axis direction (third direction). At least one of the plurality of convex portions and at least one of the plurality of concave portions abut in the Y-axis direction (third direction), thereby restricting the movement of the spacer 221 in the Y-axis direction (third direction) relative to the side member 240. In this embodiment, the movement of all the spacers 220 (all the spacers 221 and all the spacers 222) in the Y-axis direction relative to the side member 240 is restricted by the same configuration as described above. Therefore, the movement of all the spacers 220 is collectively restricted by the side member 240, and the movement of all the energy storage elements 210 is also collectively restricted.

The spacer protrusions 281 and 282 are disposed outside the end of the side member 240 in the Y-axis direction (third direction) and protrude toward the side member 240. That is, the spacer protrusion 281 is disposed in the negative Y-axis direction of the side member 240, and the spacer protrusion 282 is disposed in the positive Y-axis direction of the side member 240. As a result, the length of the side member 240 in the Y-axis direction is shorter than that of the spacer 221. Therefore, the length of the side member 240 in the Y-axis direction is shorter than that of the storage element 210. In this way, the length of the side member 240 in the Y-axis direction (third direction) is shorter than at least one of the storage element 210 and the spacer 221 (both in this embodiment). Note that, when an insulating sheet is disposed on the outer surface of the storage element 210, it is preferable that the length of the side member 240 in the Y-axis direction is shorter than that of the insulating sheet from the viewpoint of improving the insulation of the storage element 210 and the side member 240.

With the above configuration, the side protrusion 241 of the side member 240 is disposed in a position facing the first protrusions 284a, 286a, 288a, etc. (hereinafter referred to as the first protrusions 284a, etc.) of the spacer 221 in the Y-axis direction (third direction). Similarly, the side protrusion 241 is disposed in a position facing the second protrusions 286b, 288b, etc. (hereinafter referred to as the second protrusions 286b, etc.) in the Y-axis direction (third direction). Furthermore, the side protrusion 241 is disposed in a position facing the third protrusions 284c, 286c, 288c, etc. (hereinafter referred to as the third protrusions 284c, etc.) in the X-axis direction (second direction). In this way, the side protrusion 241 is also an example of an opposing portion disposed in a position facing the first protrusions 284a, etc.

That is, the first protrusions 284a, etc. protrude toward the side convex portion 241 (opposing portion) in the Y-axis direction. The second protrusions 286b, etc. are disposed at positions sandwiching the side convex portion 241 (opposing portion) between the first protrusions 286a, etc., and protrude toward the side convex portion 241 (opposing portion) in the opposite direction to the direction in which the first protrusion 286a protrudes in the Y-axis direction (third direction). The third protrusions 284c, etc. protrude toward the side convex portion 241 (opposing portion) in the X-axis direction (second direction). Furthermore, the wall portion 284e is disposed facing the side convex portion 241 (opposing portion) in the Y-axis direction (third direction). And, since no protrusion is formed on the wall portion 284e, the surface of the wall portion 284e facing the side convex portion 241 (opposing portion) has a shape (flat surface) along the side convex portion 241 (opposing portion). As a result, the wall portion 284e comes into surface contact with the side convex portion 241.

9 and 11, the energy storage device 10 includes two sets of energy storage elements 210 and spacers 221 at positions sandwiching the side member 240 in the X-axis direction (second direction). The spacers 221 and the side member 240 have multiple convex portions on one side and multiple concave portions on the other side of the side member 240 in the X-axis direction (second direction). That is, the side member 240 is disposed between the side wall portion 280a of the spacer 221 disposed in the Z-axis direction of the energy storage element 211 and the side wall portion 280b of the spacer 221 disposed in the Z-axis direction of the energy storage element 212. The portion of the side member 240 on the negative X-axis direction side and the side wall portion 280a have the above-mentioned configuration of convex portions and concave portions, and the portion of the side member 240 on the positive X-axis direction side and the side wall portion 280b have the above-mentioned configuration of convex portions and concave portions.

Furthermore, as shown in FIG. 11, the protruding portion 113 of the exterior body main body 110 of the exterior body 100 has a male threaded portion 113a that protrudes in the arrangement direction (Z-axis direction) of the pair of end members 230 (231, 232). This male threaded portion 113a penetrates the bottom wall portion 111 of the exterior body main body 110 and the opening 231b of the end member 231, and is screwed into the female threaded portion of the opening 244 of the side protrusion 241 of the side member 240. As a result, the bottom wall portion 111 of the exterior body main body 110 is fixed to the side member 240 with the end member 231 sandwiched between them.

The energy storage unit 200 is adhered to the exterior body 100 by the adhesive 114. In this embodiment, the adhesive 114 is an adhesive, but an adhesive other than an adhesive, such as double-sided tape, may be used as the adhesive 114. Specifically, the adhesive 114 is disposed within an area surrounded by ribs 111a formed on the bottom wall portion 111 of the exterior body main body 110 of the exterior body 100, and the energy storage unit 200 is adhered to the bottom wall portion 111 of the exterior body main body 110 by the adhesive 114. In other words, the energy storage unit 200 is adhered to the exterior body 100 at a position different from the protrusion 113 and the opening 244.

When manufacturing the energy storage device 10, for example, the side member 240 is positioned with a jig using the end on the negative Y-axis side as a reference, and placed relative to the energy storage element 210 and the spacer 220. The energy storage element 210 and the spacer 220 are then restrained by the end member 230 and the side member 240, and the energy storage unit 200 is constructed by welding the bus bar 250 to the energy storage element 210, etc., and inserted into the exterior body 100. The energy storage unit 200 is then fixed to the exterior body 100 by the protrusion 113, and the energy storage unit 200 is adhered to the exterior body 100 by the adhesive 114 that has been placed (applied) in advance.

[7. Description of Effects]
As described above, according to the energy storage device 10 according to the embodiment of the present invention, the spacer 221 has the first protrusions 284a and the like protruding in the third direction (Y-axis direction), and the side member 240 has an opposing portion (side convex portion 241) opposing the first protrusions 284a and the like in the third direction. In this way, by providing the first protrusions 284a and the like protruding in the third direction and opposing the opposing portion on the spacer 221, even if a gap is formed between the wall portion 284d and the like on which the first protrusions 284a and the like are provided and the opposing portion, the first protrusions 284a and the like can fill the gap. In other words, even if a gap (clearance) for absorbing manufacturing tolerances is provided between the wall portion 284d and the opposing portion in the third direction, the first protrusions 284a and the like can prevent a gap from being formed between the spacer 221 and the side member 240. This makes it possible to prevent the position of the spacer 221 from being shifted relative to the side member 240.

In particular, the movement of the energy storage element 210 and the spacer 221 is suppressed by the end member 230 in the first direction (Z-axis direction), and the movement of the spacer 221 can be suppressed by the side member 240 in the second direction (X-axis direction), but the movement may not be suppressed in the third direction (Y-axis direction). For this reason, by providing the spacer 221 with a first protrusion 284a or the like that protrudes in the third direction, it is possible to suppress the position of the spacer 221 from shifting relative to the side member 240 in the third direction. This allows the energy storage element 210 to be positioned in the third direction, and the electrode terminal 210b of the energy storage element 210 to be positioned in the third direction, so that poor joining when joining the electrode terminal 210b and the bus bar 250 can be suppressed. In other words, it is possible to suppress the position of all the spacers 220 from shifting relative to the side member 240 in the third direction, so that all the energy storage elements 210 can be positioned in the third direction. This allows the electrode terminals 210b of all the energy storage elements 210 to be positioned in the third direction, thereby preventing poor joining between the electrode terminals 210b and the busbar 250.

In addition, in the spacer 221, the surface of the wall portion 284e that faces the first protrusion 284a and faces the opposing portion (side convex portion 241) has a shape that conforms to the opposing portion. In this way, the wall portion 284e that faces the first protrusion 284a of the spacer 221 has a shape that conforms to the opposing portion of the side member 240, so that the spacer 221 can be positioned relative to the side member 240 based on the wall portion 284e. This makes it possible to prevent the position of the spacer 221 from shifting relative to the side member 240.

In addition, by arranging the wall portion 284e facing the first protrusion 284a of the spacer 221 at the end of the spacer 221, the spacer 221 can be positioned relative to the side member 240 using the end of the spacer 221 as a reference. This improves the positioning accuracy of the end side of the spacer 221. Therefore, by arranging the electrode terminal 210b of the energy storage element 210 at the end side of the spacer 221, the positioning accuracy of the electrode terminal 210b can be improved, and poor joining can be suppressed when joining the electrode terminal 210b and the bus bar 250.

The spacer 221 also has second protrusions 286b etc. that protrude toward the opposing portion (side convex portion 241) of the side member 240 at a position where the opposing portion is sandwiched between the first protrusions 286a etc., so that the opposing portion can be sandwiched between the first protrusions 286a etc. and the second protrusions 286b etc. This makes it possible to further prevent gaps from being formed between the spacer 221 and the opposing portion, and therefore makes it possible to further prevent the position of the spacer 221 from shifting relative to the side member 240.

In addition, since the spacer 221 has a third protrusion 284c that protrudes toward the opposing portion (side protrusion 241) of the side member 240 in the second direction, it is possible to prevent a gap from being formed between the spacer 221 and the opposing portion in the second direction as well. This makes it possible to further prevent the position of the spacer 221 from being shifted relative to the side member 240.

In addition, one of the spacer 221 and the side member 240 has a plurality of convex portions (side convex portion 241), and the other has a plurality of concave portions (spacer concave portion 284, etc.) into which the plurality of convex portions are inserted. At least one of the plurality of convex portions and at least one of the plurality of concave portions abut in the third direction (Y-axis direction), thereby restricting the movement of the spacer 221 in the third direction relative to the side member 240. In this way, since the spacer 221 and the side member 240 have a plurality of convex portions and a plurality of concave portions, if only one convex portion and one concave portion can abut, the movement of the spacer 221 relative to the side member 240 can be restricted. If two or more convex portions and two or more concave portions abut, the movement of the spacer 221 relative to the side member 240 can be more firmly restricted. In addition, since the energy storage element 210 is arranged in the first direction (Z-axis direction) and the side member 240 is arranged in the second direction (X-axis direction), the spacer 221 is difficult to move in the first and second directions, but is easy to move in the third direction (Y-axis direction). Therefore, by restricting the movement of the spacer 221 in the third direction relative to the side member 240, the movement of the spacer 221 relative to the side member 240 can be effectively restricted.

In addition, in the spacer 221 and the side member 240, the positions of the recesses (spacer recesses 284, etc.) and the protrusions (side protrusions 241) in the third direction (Y-axis direction) may be misaligned due to dimensional tolerances during manufacturing. For this reason, the widths of at least two recesses in the third direction or the widths of at least two protrusions in the third direction are made different. As a result, when the two protrusions are inserted into the two recesses, a gap is generated between a pair of walls (e.g., walls 288d and 288e) of one recess and one protrusion, and the gap can absorb the misalignment between the one recess and the one protrusion. Therefore, the protrusions can be easily inserted into the recesses, and the movement of the spacer 221 relative to the side member 240 can be easily restricted.

In addition, due to dimensional tolerances during manufacturing, among the multiple recesses and multiple protrusions, when the recesses (spacer recesses 284) and protrusions at one end are used as a reference, the positional deviation of the recesses and protrusions becomes greater as they move from the recesses and protrusions at one end in the third direction (Y-axis direction) toward the recesses (spacer recesses 288) and protrusions at the other end. For this reason, the width of the recess in the third direction is made larger as it moves from the recess at one end to the recess at the other end in the third direction. As a result, the gap between the pair of walls of the recess and the protrusions becomes larger as it moves from one end to the other end in the third direction, so that the positional deviation of the recesses and protrusions can be absorbed. Therefore, the protrusions can be easily inserted into the recesses, so that the movement of the spacer 221 relative to the side member 240 can be easily restricted.

In addition, since the side member 240 has the side protrusion 241, the width is increased at the position of the side protrusion 241, so that it is easy to fix it to another member (such as the end member 230 or the exterior body 100) at the position of the side protrusion 241. In other words, by fixing the side protrusion 241 to another member, the side member 240 can be easily fixed to the other member. This makes it possible to restrict the movement of the side member 240, which is a member for restricting the movement of the spacer 221. In addition, by fixing the side protrusion 241 to another member, components such as weld nuts and press-fit nuts are no longer necessary, making it possible to reduce the number of parts and to save space.

The side member 240 can be fixed to two other different members (the end member 230 and the exterior body 100, etc.) using the two side protrusions 241 of the side member 240. This can further restrict the movement of the side member 240, which is a member for restricting the movement of the spacer 221. It can also further reduce the number of parts and further reduce space.

In addition, the movement of the spacer 221 in the third direction (Y-axis direction) relative to the side member 240 can be restricted by the multiple convex portions (side convex portions 241) and multiple concave portions (spacer concave portions 284, etc.) of the spacer 221 and the side member 240. Therefore, there is little need to cover the spacer 221 with the side member 240 to restrict its movement in the third direction. Since the movement of the spacer 221 in the third direction is restricted, the movement of the storage element 210 in the third direction can also be restricted, so there is little need to cover the storage element 210 with the side member 240 to restrict its movement in the third direction. Therefore, the length of the side member 240 in the third direction can be made shorter than at least one of the storage element 210 and the spacer 221, thereby saving space.

In addition, when the side member 240 is formed of a conductive material such as metal, shortening the side member 240 reduces the size of the conductive material, thereby improving the insulation between the energy storage element 210 and the side member 240. In particular, when an insulating sheet is provided on the surface of the energy storage element 210 facing the side member 240 (e.g., the short side surface) and no insulating sheet is provided on the adjacent surface of the opposing surface (e.g., the bottom surface), shortening the side member 240 increases the distance between the adjacent surface and the side member 240. This increases the creepage distance between the energy storage element 210 and the side member 240, thereby improving the insulation between the energy storage element 210 and the side member 240.

In addition, since the movement of the spacer 221 in the third direction relative to the side member 240 can be restricted by the multiple convex portions and multiple concave portions of the spacer 221 and the side member 240, there is little need to cover the spacer 221 with the side member 240 to restrict the movement in the third direction. Therefore, the spacer 221 can be arranged outside the end of the side member 240 in the third direction, which can save space. However, if the spacer 221 is arranged outside the end of the side member 240 in the third direction, the outer part of the spacer 221 is not reinforced by the side member 240 and is therefore easily damaged. For this reason, the spacer convex portions 281 and 282 that protrude toward the side member 240 are formed in the outer part of the spacer 221. As a result, the thickness of the outer part of the spacer 221 is increased, which reinforces the outer part, thereby suppressing damage to the spacer 221.

In addition, two sets of storage elements 210 and spacers 221 are arranged at positions sandwiching the side member 240, and on both sides of the side member 240, one of the spacers 221 and the side member 240 has multiple convex portions, and the other has multiple concave portions. This makes it possible to restrict movement of the spacers 221 relative to the side member 240 on both sides of the side member 240. Therefore, since movement of the storage elements 210 can be restricted on both sides of the side member 240, movement of the storage elements 210 on both sides of the side member 240 can be suppressed even due to vibration or impact. Furthermore, the bus bar 250 can be easily connected to the storage elements 210 on both sides of the side member 240.

The energy storage unit 200 also has a side member 240 that connects the pair of end members 230, and one of the exterior body 100 and the side member 240 has a protrusion 113 that protrudes toward the other, and the other has an opening 244 into which the protrusion 113 is inserted. In this way, the protrusion 113 is provided on one of the exterior body 100 and the side member 240, and an opening 244 is formed on the other, and the protrusion 113 of the one is inserted into the opening 244 of the other. This allows the side member 240 to be fixed and positioned to the exterior body 100, so that the side member 240 can be used to easily fix the energy storage element 210 within the exterior body 100.

In addition, the protrusions 113 of one of the exterior body 100 and the side member 240 are fixed to the other within the opening 244 of the other, so that the side member 240 can be fixed to the exterior body 100. This makes it possible to easily fix the energy storage element 210 within the exterior body 100 by utilizing the side member 240.

The side member 240 is fixed to the end member 230 at a position adjacent to one of the protrusions 113 and the other of the opening 244 of the exterior body 100 and the side member 240. This separates the fixing position of the side member 240 and the exterior body 100 from the fixing position of the side member 240 and the end member 230, and allows the two fixing positions to be closer together. This makes it possible to prevent the fixing of the side member 240 and the exterior body 100 and the fixing of the side member 240 and the end member 230 from affecting each other, ensuring the fastening force of each and saving space.

The side member 240 is fixed to the end member 230 in the same direction as the protruding direction of one of the protruding portions 113 of the exterior body 100 and the side member 240. This allows the side member 240 and the exterior body 100 to be fixed and the side member 240 and the end member 230 to be fixed in the same direction. In this way, by aligning the fixing directions of the side member 240 with the exterior body 100 and the end member 230, it is possible to easily fix both, which may be preferable. If the side member 240 can be easily fixed to the exterior body 100 and the end member 230, the energy storage element 210 can be easily fixed within the exterior body 100.

In addition, by having one of the protruding portions 113 of the exterior body 100 and the side member 240 protrude in the alignment direction of the pair of end members 230, the side member 240 and the exterior body 100 can be fixed in that alignment direction. Here, it may be preferable to fix the side member 240 and the exterior body 100 in the alignment direction of the pair of end members 230, as this makes the fixing easier. If the side member 240 and the exterior body 100 can be easily fixed, the energy storage element 210 can be easily fixed within the exterior body 100.

In addition, in the side member 240, the first side portion (side convex portion 241b) in which one of the protrusions 113 of the exterior body 100 and the side member 240 or the other opening 244 is arranged is thicker than the second side portion (side concave portion 242) adjacent to the first side portion. In this way, in the side member 240, by making the first side portion thicker than the second side portion, the protrusion 113 or the opening 244 can be easily formed in the first side portion. This makes it easy to realize a configuration in which one of the protrusions 113 of the exterior body 100 and the side member 240 can be inserted into the other opening 244, so that the storage element 210 can be easily fixed in the exterior body 100. In addition, by making the thickness of the first side portion thicker, the strength of the first side portion can be ensured, and by making the thickness of the second side portion thinner, the amount of material used can be reduced and the weight can be reduced.

In addition, by adhering the energy storage unit 200 to the exterior body 100 at a position different from one of the protrusions 113 and the other of the openings 244 of the exterior body 100 and the side member 240, the energy storage element 210 can be easily and firmly fixed within the exterior body 100.

[8. Description of Modifications]
Although the power storage device 10 according to the embodiment of the present invention (including its modified examples) has been described above, the present invention is not limited to this embodiment. In other words, the embodiment disclosed here is illustrative and not restrictive in all respects, and the scope of the present invention includes all modifications within the meaning and scope equivalent to the claims.

For example, in the above embodiment, a plurality of spacers 220 are arranged, but only one spacer 220 may be arranged. In other words, only one spacer 221 may be arranged, only one spacer 222 may be arranged, or a configuration in which either spacer 221 or spacer 222 is not arranged may be used. Even if spacer 221 is not arranged, spacer 222 can perform the same function as spacer 221 by having a configuration of convex portions and concave portions, etc., similar to spacer 221 described above.

In the above embodiment, the spacer 221 is configured so that the width between the pair of walls gradually increases from the spacer recess 284 at the end in the negative Y-axis direction toward the spacer recess 288 at the end in the positive Y-axis direction. However, the spacer 221 may be configured so that the width between the pair of walls gradually increases from the spacer recess 288 toward the spacer recess 284, or the width may be any size as long as at least two spacer recesses have different widths. Alternatively, the spacer recesses 284 to 288 may all have the same width.

In addition, the side member 240 has a plurality of side protrusions 241 all having the same width in the Y-axis direction (third direction), but at least two of the plurality of side protrusions 241 may have different widths in the Y-axis direction. For example, the width of the plurality of side protrusions 241 in the Y-axis direction (third direction) may be smaller from the side protrusion 241 at one end in the Y-axis direction (third direction) to the side protrusion 241 at the other end. Specifically, the width in the Y-axis direction may be gradually smaller from the side protrusion 241 at the end in the negative Y-axis direction to the side protrusion 241 at the end in the positive Y-axis direction. This also allows the gap between the side protrusion 241 and the wall portion in the Y-axis direction of the spacer recesses 284 to 288 to be larger from the end in the negative Y-axis direction to the end in the positive Y-axis direction, so that positional deviations due to dimensional tolerances during manufacturing can be absorbed.

In the above embodiment, protrusions such as the first protrusion 284a, the second protrusion 286b, and the third protrusion 284c are provided on the wall portion of the spacer 221 facing the side member 240. However, the spacer 221 does not need to be provided with any of these protrusions. Alternatively, instead of the protrusions on the spacer 221, a protrusion protruding toward the spacer 221 may be provided on the wall portion of the side member 240 facing the spacer 221.

In the above embodiment, the side protrusions 241 of the side members 240 are portions that protrude on both sides in the X-axis direction, but they may protrude only on one side in the X-axis direction.

In the above embodiment, the protrusion 113 of the exterior body 100 is a bolt, and the male thread of the bolt is screwed into the opening 244 formed in the side member 240 to be fixed. However, the protrusion 113 may be a protrusion, the opening 244 may be a recess or a through hole, and the protrusion 113 may be inserted into the opening 244 and pressed or fitted to fix the side member 240 to the exterior body 100. Alternatively, the protrusion 113 may be a protrusion, the opening 244 may be a recess or a through hole, and the protrusion 113 may be inserted and positioned without being fixed to the opening 244. In this case, the energy storage unit 200 is adhered to the exterior body 100 by the adhesive 114, so that the energy storage element 210 can be fixed within the exterior body 100.

In the above embodiment, the exterior body 100 has a protrusion 113 that protrudes toward the side member 240, and the side member 240 has an opening 244 into which the protrusion 113 is inserted. However, the side member 240 may have a protrusion that protrudes toward the exterior body 100, and the exterior body 100 may have an opening into which the protrusion is inserted. In other words, it is sufficient that one of the exterior body 100 and the side member 240 has a protrusion that protrudes toward the other, and the other has an opening into which the protrusion is inserted.

In the above embodiment, the energy storage unit 200 has two energy storage elements 210 (211 and 212) arranged in the X-axis direction. However, the energy storage unit 200 may have three or more energy storage elements 210 arranged in the X-axis direction, or may have only one energy storage element 210 in the X-axis direction.

In the above embodiment, any of the plurality of spacers 221 may not have the above configuration, any of the plurality of side members 240 may not have the above configuration, and any of the plurality of storage elements 210 may not have the above configuration.

In the above embodiment, the energy storage device 10 does not need to include all of the components described above. For example, the energy storage device 10 does not need to include components (members or parts) that do not contribute to the above-mentioned effects or that can achieve the above-mentioned effects without them.

Any combination of the components included in the above embodiment and its variations is also within the scope of the present invention.

The present invention can be realized not only as an energy storage device 10, but also as a combination of a spacer 220 and a side member 240, or as a spacer 220.

The present invention can be applied to a storage device equipped with a storage element such as a lithium-ion secondary battery.

REFERENCE SIGNS LIST 10 Energy storage device 100 Exterior body 110 Exterior body main body 111 Bottom wall portion 111a Rib 113, 230a, 321 Protrusion 113a Male thread portion 114 Adhesive body 200 Energy storage unit 210, 211, 212 Energy storage element 210a Container 210b Electrode terminal 220, 221, 222 Spacer 230, 231, 232 End member 230b, 230c, 231b, 232b, 231c, 232c, 243, 244 Opening 240 Side member 241, 241a, 241b Side protrusion 242 Side recess 250 Bus bar 260 Spacer main body 270 Front wall portion 280, 280a, 280b Side wall portions 281, 282, 283 Spacer convex portions 284, 285, 286, 287, 288 Spacer recesses 284a, 286a, 288a First projections 284c, 286c, 288c Third projections 284d, 284e, 284f, 286d, 286e, 286f, 288d, 288e, 2 88f wall portion 286b, 288b second protrusion 290 rear wall portion

Claims (5)

An electricity storage device including electricity storage elements and spacers arranged side by side in a first direction,
a side member disposed adjacent to the spacer in a second direction intersecting the first direction,
the spacer has a first protrusion protruding in a third direction intersecting the first direction and the second direction,
the side member has an opposing portion disposed at a position opposing the first protrusion in the third direction. The spacer further comprises:
a wall portion facing the first protrusion in the third direction,
The power storage device according to claim 1 , wherein the wall portion is disposed opposite the opposing portion in the third direction, and a surface of the wall portion facing the opposing portion has a shape that conforms to the opposing portion. The power storage device according to claim 2 , wherein the wall portion is disposed at an end portion of the spacer in the third direction. The spacer further comprises:
The energy storage device according to claim 1 , further comprising a second protrusion disposed at a position sandwiching the opposing portion between the first protrusion and the second protrusion, the second protrusion protruding toward the opposing portion in a direction opposite to a direction in which the first protrusion protrudes in the third direction. The spacer further comprises:
The power storage device according to claim 1 , further comprising a third protrusion protruding toward the opposing portion in the second direction.

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