Patent Description:
Conventionally, an energy storage apparatus including an energy storage device and a substrate is widely known. Patent Document <NUM> discloses a vehicle battery system (energy storage apparatus) including a battery block made up of a plurality of battery cells (energy storage devices) and a circuit board (substrate) that detects a state of each battery cell, with the circuit board fixed to the battery block.

SUMMARY OF THE INVENTIONThe present invention is defined by the appended independent claim <NUM>.

In the energy storage apparatus, a member (hereinafter referred to as a lateral member) may be disposed lateral to the substrate. In such a case, there is a possibility that the state of penetration of the through member into the substrate cannot be grasped. When the state of penetration of the through member into the substrate cannot be grasped, there is a possibility that a defect due to attachment failure or the like of the through member to the substrate occurs.

An object of the present invention is to provide an energy storage apparatus in which a state of penetration of a through member into a substrate can be easily grasped.

An energy storage apparatus according to one aspect of the present invention includes: an energy storage device; a substrate in which a through hole penetrating a main surface is formed; a through member that penetrates the through hole; and a lateral member disposed lateral to the substrate and covering a side surface of the substrate. The lateral member includes an opening through which at least one of two portions of the through member, the two portions sandwiching the through hole, is visually recognizable from an outside, wherein the lateral member is a busbar frame on which a busbar connected to the energy storage device is mounted, and the busbar frame includes: a frame body, and a wall, in which the opening is formed, that projects from the frame body and covers the side surface of the substrate.

The present invention can be realized not only as such an energy storage apparatus but also as a lateral member including the opening and can also be realized as a lateral member, a substrate, and a through member.

According to the energy storage apparatus of the present invention, the state of penetration of the through member into the substrate can be easily grasped.

In Patent Document <NUM> described above, a voltage detection line (hereinafter referred to as a through member) connected to an electrode terminal of an energy storage device is fixed to a substrate in a state where the voltage detection line penetrates the through hole of the substrate (cf. Fig. <NUM> and the like of Patent Document <NUM>). In the energy storage apparatus, various members are disposed in a small space in order to achieve space saving or the like, and thus, a member (hereinafter referred to as a lateral member) may be disposed lateral to the substrate. The inventor of the present application has found that in such a case, there is a possibility that the state of penetration of the through member into the substrate, such as whether the through member is reliably fixed to the substrate, cannot be grasped due to a difficulty in confirming the vicinity of the through hole of the substrate from the side of the substrate. When the state of penetration of the through member into the substrate cannot be grasped, there is a possibility that a defect due to attachment failure or the like of the through member to the substrate occurs.

The present invention has been made by the inventor of the present application focusing newly on the above problem, and an object of the present invention is to provide an energy storage apparatus in which a state of penetration of a through member into a substrate can be easily grasped.

An energy storage apparatus according to one aspect of the present invention includes: an energy storage device; a substrate in which a through hole penetrating a main surface is formed; a through member that penetrates the through hole; and a lateral member disposed lateral to the substrate and covering a side surface of the substrate. The lateral member includes an opening through which at least one of two portions of the through member, the two portions sandwiching the through hole, is visually recognizable from an outside.

According to this, in the energy storage apparatus, the lateral member disposed lateral to the substrate and covering the side surface of the substrate includes the opening through which at least one of two portions, sandwiching the through hole, in the through member that penetrates the through hole of the substrate is visually recognizable from the outside. In this manner, the opening is formed in the lateral member, and at least one of the two portions of the through member sandwiching the through hole of the substrate is made visually recognizable from the outside. Thereby, the portion penetrating the through hole of the through member is visually recognizable from the outside of the lateral member through the opening, so that the state of penetration of the through member into the substrate can be easily grasped.

The opening may be formed such that a portion closer to the energy storage device out of the two portions is visually recognizable.

According to this, the opening of the lateral member is formed such that the portion closer to the energy storage device out of the two portions sandwiching the through hole in the through member can be visually recognized. In the through member, the portion closer to the energy storage device out of the two portions sandwiching the through hole is located inside the energy storage apparatus, and it is thus difficult to grasp the state of the through member. Accordingly, an opening is formed in the lateral member such that the portion closer to the energy storage device can be visually recognized. As a result, the portion of the through member closer to the energy storage device, the portion being in a state of penetration difficult to grasp, is visually recognizable from the outside of the lateral member through the opening, so that the state of penetration of the through member can be easily grasped.

The through member may be a busbar connected to the energy storage device, and the busbar may include a busbar body, and a protrusion that projects from the busbar body, penetrates the through hole, and is joined to the substrate, and the opening may be formed such that a joined state of the protrusion to the substrate is visually recognizable.

According to this, the through member is the busbar connected to the energy storage device, and the opening of the lateral member is formed such that the joining state of the protrusion, which penetrates the through hole of the busbar and is joined to the substrate, can be visually recognized. In order to measure the voltage of the energy storage device, a protrusion may be formed on the busbar, and the protrusion may be allowed to penetrate the through hole of the substrate and be joined (e.g., soldered) to the substrate. In this case, it is necessary to check whether the protrusion of the busbar is joined to the substrate (e.g., whether a solder fillet is formed favorably). Therefore, the opening is formed in the lateral member, and the joined state of the protrusion to the substrate can be visually recognized. As a result, the joined state of the protrusion of the busbar to the substrate can be easily grasped, so that it is possible to prevent stress concentration on the protrusion due to joint failure and to prevent the breakage of the protrusion.

The lateral member is a busbar frame on which a busbar connected to the energy storage device is mounted, and the busbar frame includes a frame body, and a wall that projects from the frame body and covers a side surface of the substrate, and in which the opening is formed.

According to this, the lateral member is the busbar frame on which the busbar is placed, and the busbar frame includes the wall that covers the side surface of the substrate, and in which the opening is formed. In the energy storage apparatus, the busbar frame may be provided with a wall that covers the side surface of the substrate. For the purpose of preventing the movement (vibration) of the energy storage device in the outer case of the energy storage apparatus, or some other purpose, a wall may be provided on the busbar frame, and the wall may be engaged with the cover of the outer case to fix the busbar frame to the outer case. Alternatively, a wall may be provided on the busbar frame as a guide for disposing the cover on the outer case. In such a case, there is a possibility that the state of penetration of the through member into the substrate cannot be grasped due to the wall of the busbar frame. Therefore, the opening is formed in the wall of the busbar frame to make the state of penetration of the through member into the substrate visually recognizable. As a result, even if the wall is provided in the busbar frame, the state of penetration of the through member into the substrate can be easily grasped.

The opening may comprise a notch or a through hole formed in the lateral member.

According to this, since the opening of the lateral member is a notch or a through hole formed in the lateral member, by forming the notch or the through hole in the lateral member, it is possible to easily form the opening through which the state of penetration of the through member into the substrate can be visually recognized.

The through member may include a long side surface and a short side surface on a side surface in directions intersecting with a direction of penetration into the through hole, and the opening may be disposed to face the long side surface of the through member.

According to this, the opening of the lateral member is disposed to face the long side surface of the through member. As described above, by disposing the opening of the lateral member to face the long side surface of the through member instead of the short side surface thereof, it is possible to visually recognize the long side surface side of the through member instead of the short side surface thereof. This makes it easy to visually recognize the state of penetration of the through member, so that the state of penetration of the through member into the substrate can be easily and more reliably grasped.

Hereinafter, an energy storage apparatus according to an embodiment of the present invention (including a modification thereof) will be described with reference to the drawings. An embodiment described below illustrates a comprehensive or specific example. Numeral values, shapes, materials, components, placement positions and connection forms of the components, manufacturing steps, a sequence of the manufacturing steps, and the like shown in the following embodiment are only examples and are not intended to limit the present invention. In the drawings, dimensions and the like are not illustrated strictly. In the drawings, the same or similar components are denoted by the same reference numerals.

In the following description and drawings, a direction in which a pair of (positive-electrode-side and negative-electrode-side) electrode terminals are disposed in one energy storage device or a direction in which the short side surface of a case of the energy storage device faces is defined as an X-axis direction. A direction in which the energy storage devices are arranged or a direction in which the long side surface of the case of the energy storage device is defined as a Y-axis direction. A direction in which the body and the lid of the outer case of the energy storage apparatus are disposed, a direction in which the energy storage devices, the busbar frame, the busbar, and the substrate are disposed, or a vertical direction is defined as a Z-axis direction. The X-axis direction, the Y-axis direction, and the Z-axis direction are mutually intersecting (orthogonal in the present embodiment) directions. It is conceivable that the Z-axis direction may not be the vertical direction depending on the use aspect, but for convenience of description, a description will be given below with the Z-axis direction as the vertical direction.

In the following description, an X-axis plus direction indicates an arrow direction of the X-axis, and an X-axis minus direction indicates a direction opposite to the X-axis plus direction. The same applies to the Y-axis direction and the Z-axis direction. Expressions indicating relative directions or postures, such as parallel and orthogonal, strictly include cases where the directions or postures are not the same. Two directions being orthogonal to each other not only means that the two directions are completely orthogonal to each other, but also means that the two directions are substantially orthogonal to each other, the two directions being orthogonal includes a difference of about several percent.

First, an energy storage apparatus <NUM> according to the present embodiment will be generally described. <FIG> is a perspective view illustrating the appearance of the energy storage apparatus <NUM> according to the present embodiment. <FIG> is an exploded perspective view illustrating each component when the energy storage apparatus <NUM> according to the present embodiment is disassembled.

The energy storage apparatus <NUM> is an apparatus capable of charging electricity from the outside and discharging electricity to the outside and has a substantially rectangular parallelepiped shape in the present embodiment. The energy storage apparatus <NUM> is a battery module (assembled battery) used for power storage application, power supply application, or the like. Specifically, the energy storage apparatus <NUM> is used as a battery or the like for driving or starting an engine of a moving body such as an automobile, a motorcycle, a watercraft, a ship, a snowmobile, an agricultural machine, a construction machine, or a railway vehicle for electric railways. Examples of the automobile include an electric vehicle (EV), a hybrid electric vehicle (HEV), a plug-in hybrid electric vehicle (PHEV), and a gasoline vehicle. Examples of the railway vehicle for electric railways include a train, a monorail, and a linear motor car. The energy storage apparatus <NUM> can also be used as a stationary battery or the like used for home use, a generator, or the like.

As illustrated in <FIG>, the energy storage apparatus <NUM> includes an outer case <NUM>, and as illustrated in <FIG>, a plurality of energy storage devices <NUM>, a busbar frame <NUM>, a busbar <NUM>, a substrate <NUM>, and the like are housed inside the outer case <NUM>. The energy storage apparatus <NUM> may include a spacer disposed between the plurality of energy storage devices <NUM>, a binding member (side plate, end plate, etc.) binding the plurality of energy storage devices <NUM>, and the like.

The outer case <NUM> is a case (module case) having a box shape (substantially rectangular parallelepiped shape) which forms an outer case of the energy storage apparatus <NUM>. That is, the outer case <NUM> is disposed outside the plurality of energy storage devices <NUM>, the busbar frame <NUM>, the busbar <NUM>, the substrate <NUM>, and the like, and fixes the energy storage devices <NUM> and the like at predetermined positions for protection from an impact or the like. The outer case <NUM> is formed of, for example, an insulating member such as polycarbonate (PC), polypropylene (PP), polyethylene (PE), polystyrene (PS), a polyphenylene sulfide resin (PPS), polyphenylene ether (PPE (including modified PPE)), polyethylene terephthalate (PET), polybutylene terephthalate (PBT), polyether ether ketone (PEEK), tetrafluoroethylene-perfluoroalkyl vinyl ether (PFA), polytetrafluoroethylene (PTFE), polyethersulfone (PES), an acrylonitrile butadiene styrene (ABS) resin, or a composite material thereof, or an insulation-coated metal. Thereby, the outer case <NUM> prevents the energy storage devices <NUM> and the like from coming into contact with an external metal member or the like. The outer case <NUM> may be formed of a conductive member such as metal so long as the electric insulation properties of the energy storage device <NUM> and the like are maintained.

The outer case <NUM> includes an outer case body <NUM> constituting the body of the outer case <NUM> and an outer case lid <NUM> constituting the lid of the outer case <NUM>. The outer case body <NUM> is a bottomed rectangular cylindrical housing (casing) in which an opening is formed, and houses the energy storage devices <NUM> and the like therein. The outer case lid <NUM> is a flat rectangular member that closes the opening of the outer case body <NUM>. The outer case lid <NUM> is engaged with or fitted to the outer case body <NUM> and is joined to the outer case body <NUM> by an adhesive, heat sealing, ultrasonic welding, or the like. The outer case lid <NUM> is provided with a positive external terminal <NUM> and a negative external terminal <NUM>. The energy storage apparatus <NUM> charges electricity from the outside and discharges electricity to the outside through the positive external terminal <NUM> and the negative external terminal <NUM>.

The energy storage device <NUM> is a secondary battery (battery cell) capable of charging and discharging electricity and is specifically a nonaqueous electrolyte secondary battery such as a lithium ion secondary battery. The energy storage device <NUM> has a flat rectangular parallelepiped shape (prismatic shape), and in the present embodiment, four energy storage devices <NUM> (energy storage devices <NUM> to <NUM>) are arranged side by side in the Y-axis direction. The shape, number, arrangement position, and the like of the energy storage device <NUM> are not particularly limited. The energy storage device <NUM> is not limited to the nonaqueous electrolyte secondary battery but may be a secondary battery except for the nonaqueous electrolyte secondary battery or may be a capacitor. The energy storage device <NUM> may be not a secondary battery but a primary battery that can use stored electricity without being charged by a user. The energy storage device <NUM> may be a battery using a solid electrolyte. The energy storage device <NUM> may be a laminate-type energy storage device.

Specifically, the energy storage device <NUM> includes a case <NUM> and a pair of (positive- electrode-side and negative-electrode-side) electrode terminals <NUM>. An electrode assembly, a pair of current collectors, an electrolyte solution (nonaqueous electrolyte), and the like are accommodated in the case <NUM>, but illustration thereof is omitted. The case <NUM> is a rectangular parallelepiped (prismatic) case and is formed of a metal such as stainless steel, aluminum, an aluminum alloy, iron, or a plated steel plate. The electrode terminals <NUM> are terminals (a positive terminal and a negative terminal) electrically connected to the positive electrode plate and the negative electrode plate of the electrode assembly via the current collector and are made of aluminum, an aluminum alloy, copper, a copper alloy, or the like.

The electrode assembly is an energy storage element (power generating element) formed by stacking a positive electrode plate, a negative electrode plate, and a separator. The positive electrode plate is obtained by forming a positive active material layer on a positive electrode substrate layer that is a current collecting foil made of a metal such as aluminum or an aluminum alloy. The negative electrode plate is obtained by forming a negative active material layer on a negative electrode substrate layer that is a current collecting foil made of a metal such as copper or a copper alloy. As an active material used for each of the positive active material layer and the negative active material layer, a known material can be appropriately used so long as the material can occlude and release lithium ions. The electrode assembly may be an electrode assembly in any form such as a winding-type electrode assembly formed by winding plates (a positive electrode plate and a negative electrode plate), a layering-type (stacking-type) electrode assembly formed by layering a plurality of plate-shaped electrode plates, or a bellows-type electrode assembly formed by folding plates in a bellows shape.

The current collector is a member having conductivity and rigidity (a positive electrode current collector and a negative electrode current collector) electrically connected to the electrode terminal <NUM> and the electrode assembly. The positive electrode current collector is formed of aluminum, an aluminum alloy, or the like, similarly to the positive electrode substrate layer of the positive electrode plate, and the negative electrode current collector is formed of copper, a copper alloy, or the like, similarly to the negative electrode substrate layer of the negative electrode plate. The type of the electrolyte solution is not particularly limited so long as the electrolyte solution does not impair the performance of the energy storage device <NUM>, and various electrolyte solutions can be selected.

The busbar frame <NUM> is a flat rectangular member capable of electrically insulating the busbar <NUM> from other members and regulating the positions of the busbars <NUM>. The busbar frame <NUM> is formed of an insulating member such as PC, PP, or PE, which is similar to the outer case <NUM>. Specifically, the busbar frame <NUM> is placed above the plurality of energy storage devices <NUM> and is positioned with respect to the plurality of energy storage devices <NUM>. The busbar <NUM> is placed and positioned on the busbar frame <NUM>. Thereby, the busbar <NUM> is positioned with respect to the plurality of energy storage devices <NUM> and are joined to the electrode terminals <NUM> included in the plurality of energy storage devices <NUM> (cf.

After the joining of the busbar <NUM> to the electrode terminals <NUM> of the energy storage devices <NUM>, the substrate <NUM> is mounted and fixed on the busbar frame <NUM> (cf. As described above, the busbar frame <NUM> also has a function of mounting and fixing the substrate <NUM>. The busbar frame <NUM> has a function of reinforcing the outer case <NUM> as the inner lid of the outer case <NUM>, and a function of restricting the movement of the energy storage devices <NUM> by fixation to the outer case lid <NUM>. The configuration of the busbar frame <NUM> will be described in detail later.

The busbar <NUM> is a flat-plate-like member that is disposed above the plurality of energy storage devices <NUM> and connected (joined) to the electrode terminals <NUM> of the plurality of energy storage devices <NUM>. Thus, the busbar <NUM> connects the electrode terminals <NUM> of the plurality of energy storage devices <NUM> to each other. The busbar <NUM> connects the electrode terminals <NUM> of the energy storage devices <NUM> positioned at the ends of the plurality of energy storage devices <NUM> to the positive external terminal <NUM> and the negative external terminal <NUM>.

The busbar <NUM> is formed of a metal such as aluminum, an aluminum alloy, copper, a copper alloy, or nickel, a combination thereof, or a conductive member other than the metal. In the present embodiment, the busbars <NUM> connect the positive terminal and the negative terminal of the energy storage devices <NUM> disposed adjacently to each other to connect the four energy storage devices <NUM> in series. The aspect of the connection of the energy storage devices <NUM> is not limited to the above, and series connection and parallel connection may be combined in any manner. The configuration of the busbar <NUM> will be described in detail later.

The substrate <NUM> is a circuit board that is electrically connected to the energy storage device <NUM>, monitors the charge state and the discharge state of the energy storage device <NUM>, and controls the charge and discharge of the energy storage device <NUM>. As described above, the substrate <NUM> is placed and fixed on the busbar frame <NUM>. Specifically, the substrate <NUM> includes electric components such as a fuse, a relay, a semiconductor switch such as a field-effect transistor (FET), a shunt resistor, a thermistor, and a connector.

The substrate <NUM> monitors states such as the charge state and the discharge state of the energy storage device <NUM> by acquiring information of the voltage and the like of the energy storage device <NUM> through the busbar <NUM> or acquiring the temperature information of the energy storage device <NUM> through the thermistor. The substrate <NUM> is electrically connected to the energy storage device <NUM>, the positive external terminal <NUM>, and the negative external terminal <NUM> (that is, connected to the main current path of the energy storage device <NUM>) through the busbar <NUM> to control the charge and discharge of the energy storage device <NUM>. The substrate <NUM> may only monitor the state of the energy storage device <NUM> without controlling the charge and discharge of the energy storage device <NUM>. The configuration of the substrate <NUM> will be described in detail later.

Next, the configurations of the busbar frame <NUM>, the busbar <NUM>, and the substrate <NUM> will be described in detail. <FIG> is a perspective view illustrating a configuration of the busbar frame <NUM>, the busbar <NUM>, and the substrate <NUM> according to the present embodiment. Specifically, <FIG> is an enlarged perspective view illustrating the busbar frame <NUM>, the busbar <NUM>, and the substrate <NUM> in <FIG> in an enlarged manner.

<FIG> is a perspective view illustrating a configuration in a state where the busbar <NUM> mounted on the busbar frame <NUM> according to the present embodiment is joined to the energy storage devices <NUM>. Specifically, <FIG> is a perspective view illustrating a configuration in a state where the outer case body <NUM>, the energy storage devices <NUM>, the busbar frame <NUM>, and the busbar <NUM> illustrated in <FIG> have been assembled to each other, that is, in a state where the outer case lid <NUM> and the substrate <NUM> have been removed from the energy storage apparatus <NUM> illustrated in <FIG>. Fig. <NUM>(b) is an enlarged perspective view illustrating a protrusion <NUM> of a busbar <NUM> and an opening <NUM> formed in a wall <NUM> of the busbar frame <NUM> in <FIG> in an enlarged manner.

<FIG> is a perspective view illustrating a configuration in a state where the substrate <NUM> is fixed to the busbar frame <NUM> according to the present embodiment. Specifically, <FIG> is a perspective view illustrating a configuration in a state where the outer case body <NUM>, the energy storage devices <NUM>, the busbar frame <NUM>, the busbar <NUM>, and the substrate <NUM> illustrated in <FIG> have been assembled to each other, that is, in a state where the outer case lid <NUM> has been removed from the energy storage apparatus <NUM> illustrated in <FIG>. Fig. <NUM>(b) is an enlarged perspective view illustrating a state where the protrusion <NUM> of the busbar <NUM> in <FIG> penetrates a through hole <NUM> of the substrate <NUM> in an enlarged manner.

As illustrated in <FIG>, the busbar frame <NUM> includes a frame body <NUM> and walls <NUM>, <NUM>, <NUM>, <NUM>. The frame body <NUM> is the body of the busbar frame <NUM> and is a flat rectangular portion on which the busbar <NUM> is placed and to which the substrate <NUM> is fixed. The frame body <NUM> has an opening <NUM> for connecting the busbar <NUM> to the electrode terminal <NUM> of the energy storage device <NUM>, and a fixing portion <NUM> for fixing the substrate <NUM>.

The opening <NUM> is a rectangular through hole formed in the frame body <NUM>, and eight openings <NUM> are formed at positions facing the eight electrode terminals <NUM> of the plurality of energy storage devices <NUM>, respectively. Thereby, as illustrated in <FIG>, the busbar <NUM> (busbars <NUM> to <NUM> to be described later) can be connected (joined) to the electrode terminals <NUM> of the energy storage devices <NUM> through the openings <NUM>.

The fixing portion <NUM> is a cylindrical projection projecting in the Z-axis plus direction, and is inserted into and fixed to a through hole <NUM> formed in a substrate body <NUM> of the substrate <NUM> to be described later. In the present embodiment, four fixing portions <NUM> are inserted into and fixed to four through holes <NUM> formed in the substrate body <NUM>. Specifically, as illustrated in <FIG>, the fixing portion <NUM> is inserted into the through hole <NUM> of the substrate body <NUM> and then fixed to the substrate body <NUM> by thermal caulking. Thereby, the substrate <NUM> is fixed to the busbar frame <NUM>. A method of fixing the substrate <NUM> to the busbar frame <NUM> is not limited to thermal caulking, and any method such as screw fastening, an adhesive, welding, or the like may be used.

The walls <NUM>, <NUM>, <NUM>, <NUM> are flat and rectangular sidewalls projecting (erected) in the Z-axis plus direction from the peripheral portion of the frame body <NUM>. That is, the walls <NUM>, <NUM>, <NUM>, <NUM> are portions disposed lateral to the substrate <NUM> and covering at least a part of the side surfaces of the substrate <NUM> when the substrate <NUM> is fixed to the frame body <NUM>. The busbar frame <NUM> is an example of a lateral member covering the side surface of the substrate <NUM>. The walls <NUM>, <NUM>, <NUM>, <NUM> are provided for the purpose of guiding when the outer case lid <NUM> is disposed on the outer case body <NUM>, the purpose of restricting the movement (vibration) of the energy storage devices <NUM> in the outer case <NUM> by fixation to the outer case lid <NUM>, and some other purpose.

Specifically, the wall <NUM> is a sidewall of the frame body <NUM> on the Y-axis plus direction side and is disposed in the Y-axis plus direction of the substrate <NUM> to cover at least a part of a side surface 510b of the substrate <NUM> to be described later. That is, the openings <NUM>, <NUM> are formed in the wall <NUM>, and the side surface 510b of the substrate <NUM> is exposed from the openings <NUM>, <NUM> (cf. The openings <NUM>, <NUM> are notches penetrating in the Y-axis direction formed by recessing, in the Z-axis minus direction, the end and the center of the wall <NUM> on the X-axis minus direction side.

The wall <NUM> is a sidewall of the frame body <NUM> on the X-axis plus direction side, provided at the end thereof on the Y-axis plus direction side, and is disposed in the X-axis plus direction of the substrate <NUM> to cover at least a part of a side surface 510c of the substrate <NUM> to be described later. That is, since the wall <NUM> is opened on the Y-axis minus direction side, it can be said that an opening <NUM> is provided on the wall <NUM> on the Y-axis minus direction side, and the side surface 510c of the substrate <NUM> is exposed from the opening <NUM> (cf.

The wall <NUM> is a sidewall of the frame body <NUM> on the X-axis minus direction side, provided at the end thereof on the Y-axis plus direction side, and is disposed in the X-axis minus direction of the substrate <NUM> to cover at least a part of a side surface 510d of the substrate <NUM> to be described later. That is, since the wall <NUM> is opened on the Y-axis minus direction side, it can be said that the opening <NUM> is provided on the wall <NUM> on the Y-axis minus direction side, and the side surface 510d of the substrate <NUM> is exposed from the opening <NUM> (cf.

The wall <NUM> is a sidewall of the frame body <NUM> on the Y-axis minus direction side, is provided at the center thereof in the X-axis direction, and is disposed in the Y-axis minus direction of the substrate <NUM> to cover at least a part of a side surface 510e of the substrate <NUM> to be described later. That is, since both sides of the wall <NUM> in the X-axis direction are opened, it can be said that openings <NUM>, <NUM> are provided on both sides of the wall <NUM> in the X-axis direction, and the side surface 510e of the substrate <NUM> is exposed from the openings <NUM>, <NUM> (cf.

The busbar <NUM> includes five busbars <NUM> to <NUM>. The busbar <NUM> includes a busbar body <NUM>, a connection <NUM>, and a protrusion <NUM>. The busbar body <NUM> is the body of the busbar <NUM> and is a flat plate-like portion connected (joined) to the electrode terminal <NUM> of the energy storage devices <NUM> (specifically, the positive terminal of the energy storage device <NUM>) (cf. The connection <NUM> is a cylindrical portion projecting from the busbar body <NUM> in the Z-axis plus direction and is connected to another busbar (not illustrated) so as to be connected to the positive external terminal <NUM> through another busbar. The protrusion <NUM> is a protrusion projecting from the busbar body <NUM> in the Z-axis plus direction, penetrates the through hole <NUM> formed in the substrate <NUM> to be described later (cf. <FIG>), and is joined to the substrate <NUM>.

The busbar <NUM> includes a busbar body <NUM> and a protrusion <NUM>. The busbar body <NUM> is the body of the busbar <NUM> and is a flat plate-like portion connected (joined) to the electrode terminal <NUM> of the energy storage devices <NUM> (specifically, the negative terminal of the energy storage device <NUM> and the positive terminal of the energy storage device <NUM> may be used) (cf. The protrusion <NUM> is a protrusion projecting from the busbar body <NUM> in the Z-axis plus direction, penetrates the through hole <NUM> formed in the substrate <NUM> to be described later (cf. <FIG>), and is joined to the substrate <NUM>.

The busbar <NUM> includes a busbar body <NUM> and a protrusion <NUM>. The busbar body <NUM> is the body of the busbar <NUM> and is a flat plate-like portion that is connected (joined) to the electrode terminals <NUM> of the energy storage devices <NUM> (specifically, the negative terminal of the energy storage device <NUM> and the positive terminal of the energy storage device <NUM> may be used) (cf. The protrusion <NUM> is a protrusion projecting from the busbar body <NUM> in the Z-axis plus direction, penetrates the through hole <NUM> formed in the substrate <NUM> to be described later (cf. <FIG>), and is joined to the substrate <NUM>.

The busbar <NUM> includes a busbar body <NUM> and a connection <NUM>. The busbar body <NUM> is the body of the busbar <NUM> and is a flat plate-like portion that is connected (joined) to the electrode terminal <NUM> of the energy storage device <NUM> (specifically, the negative terminal of the energy storage device <NUM>) (cf. The connection <NUM> is a columnar portion projecting from the busbar body <NUM> in the Z-axis plus direction and is connected (fixed) to a connection member <NUM> of the substrate <NUM> to be described later to electrically connect the busbar <NUM> to the substrate <NUM> (cf.

As described above, the busbar <NUM> (busbars <NUM> to <NUM>) are sequentially connected (joined) to the electrode terminals <NUM> of the four energy storage devices <NUM> (energy storage devices <NUM> to <NUM>) to connect the four energy storage devices <NUM> in series. As a method of connecting (joining) the busbar <NUM> and the electrode terminals <NUM> of the energy storage devices <NUM>, any method may be used, like welding such as ultrasonic welding, laser welding, or resistance welding, or mechanical joining such as screw fastening or caulking joining. The busbars <NUM> to <NUM> of the busbar <NUM> has protrusions <NUM>, <NUM>, <NUM>, <NUM> penetrating the through holes <NUM> to <NUM> of the substrate <NUM>. Each of the busbars <NUM> to <NUM> as thus described is an example of a through member penetrating the through hole of the substrate <NUM>.

The substrate <NUM> includes the substrate body <NUM>, an electronic component <NUM>, and connection members <NUM>, <NUM>. The substrate body <NUM> is the body of the substrate <NUM> and is a rectangular flat-plate-like portion on which the electronic component <NUM> is mounted. In the substrate body <NUM>, a surface (upper surface) on the Z-axis plus direction side is defined as a main surface 510a, a side surface on the Y-axis plus direction side is defined as a side surface 510b, a side surface on the X-axis plus direction side is defined as a side surface 510c, a side surface on an X-axis minus direction side is defined as a side surface 510d, and a side surface on the Y-axis minus direction side is defined as a side surface 510e. That is, the main surface 510a is a plate surface of the substrate body <NUM> on which the electronic component <NUM> is mounted, and the side surfaces 510b, 510c, 510d, 510e are end surfaces surrounding the periphery of the substrate body <NUM>.

The through holes <NUM> to <NUM> and <NUM> penetrating the main surface 510a are formed in the substrate body <NUM>. Each of the through holes <NUM> to <NUM> is an oval through hole that penetrates the substrate body <NUM> in the thickness direction (Z-axis direction) and is long in the X-axis direction. The through holes <NUM> to <NUM> are formed at positions corresponding to the protrusions <NUM>, <NUM>, <NUM>, <NUM> of the busbars <NUM> to <NUM>, respectively. Specifically, the through hole <NUM> is formed in the middle in the X-axis direction of the end of the substrate body <NUM> on the Y-axis minus direction side. The through hole <NUM> is formed at the end of the substrate body <NUM> on the Y-axis minus direction side and the X-axis minus direction side. The through hole <NUM> is formed at the end of the substrate body <NUM> on the Y-axis minus direction side and the X-axis plus direction side. The through hole <NUM> is formed at the end of the substrate body <NUM> on the Y-axis plus direction side and the X-axis minus direction side.

As described above, the protrusions <NUM>, <NUM>, <NUM>, <NUM> of the busbars <NUM> to <NUM> are inserted into the through holes <NUM> to <NUM>, respectively (cf. <FIG>), and joined by soldering or the like. Thereby, the busbars <NUM> to <NUM> and the substrate body <NUM> are electrically connected, and hence the substrate <NUM> can acquire information on the voltage and the like of the energy storage device <NUM> through the busbars <NUM> to <NUM> and the electrode terminals <NUM> of the energy storage device <NUM>. A configuration in which the protrusions of the busbars <NUM> to <NUM> are joined to the substrate <NUM> will be described in detail later.

The through holes <NUM> are circular through holes formed at four corners of both ends in the X-axis direction and both ends in the Y-axis direction of the substrate body <NUM> and penetrating the substrate body <NUM> in a thickness direction (Z-axis direction) thereof. As described above, the cylindrical fixing portion <NUM> provided in the frame body <NUM> of the busbar frame <NUM> is inserted into the through hole <NUM>. That is, four through holes <NUM> are formed at positions corresponding to the four fixing portions <NUM>, and the four fixing portions <NUM> are inserted into and joined to the four through holes <NUM>, respectively (cf.

The electronic component <NUM> is a circuit component mounted on the substrate body <NUM> and is a fuse, a relay, a semiconductor switch such as a field-effect transistor (FET), a shunt resistor, a thermistor, or the like. The connection member <NUM> is a member to which the connection <NUM> of the busbar <NUM> is inserted and connected (fixed). That is, as described above, the connection member <NUM> fixes the busbar <NUM> to the substrate body <NUM> to electrically connect the substrate body <NUM> and the busbar <NUM> (cf. The connection member <NUM> is a portion connected to the negative external terminal <NUM> via another busbar (not illustrated). That is, the connection member <NUM> fixes another busbar to the substrate body <NUM> to electrically connect the substrate body <NUM> and the negative external terminal <NUM>. The connection member <NUM> and the connection member <NUM> are electrically connected via the electronic component <NUM> and the like, whereby the busbar <NUM> and the negative external terminal <NUM> are electrically connected.

Next, a configuration in which the protrusions (protrusions <NUM>, <NUM>, <NUM>, <NUM>) of the busbar <NUM> (busbars <NUM> to <NUM>) are joined to the substrate <NUM> will be described in detail. Since any of the protrusions has the same configuration to be joined to the substrate <NUM>, a configuration in which the protrusion <NUM> of the busbar <NUM> is joined to the substrate <NUM> will be described below, and description of other configurations will be omitted.

<FIG> is a perspective view, a side view, and a top view illustrating a state where the protrusion <NUM> of the busbar <NUM> according to the present embodiment is joined to the substrate body <NUM> of substrate <NUM>. Specifically, <FIG> is a perspective view illustrating a state before the protrusion <NUM> of the busbar <NUM> is joined to the substrate body <NUM> of the substrate <NUM>, and is a view similar to Fig. <NUM>(b). <FIG> is a side view of <FIG> as viewed from the side (Y-axis plus direction), and <FIG> is a top view of <FIG> as viewed from above (Z-axis plus direction). <FIG> is a perspective view illustrating a state after the protrusion <NUM> of the busbar <NUM> has been joined to the substrate body <NUM> of the substrate <NUM>, and corresponds to <FIG> is a side view when <FIG> is viewed from the side (Y-axis plus direction), and corresponds to <FIG> is a top view when <FIG> is viewed from above (the Z-axis plus direction), and corresponds to <FIG>.

First, as illustrated in <FIG>, in a state where the busbar <NUM> is mounted on the busbar frame <NUM> and is joined to the electrode terminals <NUM> of the energy storage devices <NUM>, the protrusion <NUM> of the busbar <NUM> is disposed on the Y-axis minus direction side of the openings <NUM> formed in the wall <NUM> of the busbar frame <NUM>. Specifically, the protrusion <NUM> of the busbar <NUM> has a long side surface 442a on the side surface in the Y-axis direction and a short side surface 442b on a side surface in the X-axis direction. The opening <NUM> is disposed at a position facing the long side surface 442a.

As illustrated in <FIG> and <FIG> to <NUM>(c), when the substrate <NUM> is fixed to the busbar frame <NUM>, the protrusion <NUM> of the busbar <NUM> penetrates the through hole <NUM> of the substrate body <NUM> of the substrate <NUM> from the Z-axis minus direction. In this state, as described above, the protrusion <NUM> of the busbar <NUM> has the long side surface 442a and the short side surface 442b on the side surfaces in directions (Y-axis direction and X-axis direction) intersecting with a direction of penetration (Z-axis direction) into the through hole <NUM>, and the opening <NUM> is disposed to face the long side surface 442a. That is, as viewed in the Z-axis direction, the rectangular protrusion <NUM> long in the X-axis direction is inserted into the oval through hole <NUM> long in the X-axis direction.

As illustrated in <FIG>, two portions of the protrusion <NUM> of the busbar <NUM> sandwiching the through hole <NUM> are referred to as a protrusion tip 442c and a protrusion base end 442d. That is, the protrusion tip 442c and the protrusion base end 442d are two portions of the protrusion <NUM> disposed on both sides of the through hole <NUM> in the Z-axis direction, in other words, on both sides of the substrate body <NUM> of the substrate <NUM>.

Specifically, the protrusion tip 442c is a portion of the protrusion <NUM> on the distal end side of the protrusion <NUM>, which is disposed on the Z-axis plus direction side of the through hole <NUM>. That is, the protrusion tip 442c is a portion projecting from the main surface 510a of the substrate body <NUM> in the Z-axis plus direction (the outside of the substrate <NUM>). The protrusion base end 442d is a portion of the protrusion <NUM> on the base end side of the protrusion <NUM> disposed on the Z-axis minus direction side of the through hole <NUM>. That is, the protrusion base end 442d is a portion disposed in the Z-axis minus direction (inside the substrate <NUM>) of the substrate body <NUM>, in other words, a portion closer to the energy storage device <NUM> than the protrusion tip 442c.

The opening <NUM> is disposed at a position where at least one of the protrusion tip 442c and the protrusion base end 442d can be visually recognized from the outside (Y-axis plus direction). In the present embodiment, the opening <NUM> is disposed at a position where (the long side surface 442a of) each of the protrusion tip 442c and the protrusion base end 442d can be visually recognized from the outside. That is, the opening <NUM> is a notch which is deeply cut in the Z-axis direction, and not only the protrusion tip 442c but also the protrusion base end 442d (the portion closer to the energy storage device <NUM>) is formed to be visually recognizable.

In the above configuration, as illustrated in <FIG>, the protrusion <NUM> is joined (fixed) to the substrate body <NUM> with solder <NUM>. That is, the solder <NUM> melted from the protrusion tip 442c side (Z-axis plus direction side) is applied around the through hole <NUM> on the surface (main surface 510a) of the substrate body <NUM>. Then, due to the action of gravity and surface tension, the solder <NUM> flows into the through hole <NUM>, and the solder <NUM> is disposed and solidified around the through hole <NUM> on a back surface of the substrate body <NUM> also on the protrusion base end 442d side (Z-axis minus direction side). As a result, the protrusion tip 442c is joined (fixed) to the substrate body <NUM> by the solder <NUM>, and the protrusion base end 442d is joined (fixed) to the substrate body <NUM> by solder <NUM>, thus improving the joint strength of the protrusion <NUM> to the substrate <NUM>. The solder <NUM> and the solder <NUM> are solder fillets having an oval frustum shape.

As thus described, the busbar <NUM> includes the solder <NUM> (solder <NUM> and the solder <NUM>) in the state after the protrusion <NUM> has been joined to the substrate <NUM>. In this case, the solder <NUM> and the solder <NUM> become two portions of the busbar <NUM> sandwiching the through hole <NUM>, and the solder <NUM> becomes a portion closer to the energy storage device <NUM> out of the two portions.

Since the opening <NUM> is disposed at a position where both the protrusion tip 442c and the protrusion base end 442d are visually recognizable from the outside, the solder <NUM> and the solder <NUM> are also disposed at visually recognizable positions. That is, the opening <NUM> is formed such that the fillet state of the solder <NUM> and the solder <NUM> at the protrusion tip 442c and the protrusion base end 442d can be visually recognized. In this manner, the opening <NUM> is formed such that the joined state of the protrusion <NUM> to the substrate <NUM> can be visually recognized.

That is, in the state after the protrusion <NUM> has been joined to the substrate <NUM>, the opening <NUM> is formed such that the protrusion tip 442c and the protrusion base end 442d, which are two portions of the busbar <NUM> sandwiching the through hole <NUM>, can be visually recognized from the outside. In the state after the protrusion <NUM> has been joined to the substrate <NUM>, the opening <NUM> is formed such that the solder <NUM> and the solder <NUM>, which are two portions of the busbar <NUM> sandwiching the through hole <NUM>, can be visually recognized from the outside. The opening <NUM> is formed such that portions of the protrusion tip 442c and the protrusion base end 442d exposed from the solder <NUM> and the solder <NUM> are also visible from the outside.

Similarly to the opening <NUM>, the openings <NUM>, <NUM>, <NUM> are also formed such that two portions of each of the busbars <NUM> to <NUM>, the two portions sandwiching each of the through hole <NUM> to <NUM>, can be visually recognized from the outside. That is, the opening <NUM> is formed such that two portions of the busbar <NUM> sandwiching the through hole <NUM> are visually recognizable from the X-axis plus direction. Thereby, the opening <NUM> is formed such that the joined state of the protrusion <NUM> of the busbar <NUM> to the substrate <NUM> can be visually recognized. Similarly, the openings <NUM>, <NUM> are formed such that two portions of each of the busbars <NUM>, <NUM>, the two portions sandwiching each of the through holes <NUM>, <NUM>, can be visually recognized from the Y-axis minus direction. Thereby, the openings <NUM>, <NUM> are formed such that the joined state of the protrusions <NUM>, <NUM> of the busbars <NUM>, <NUM> to the substrate <NUM> can be visually recognized.

As described above, the energy storage apparatus <NUM> according to the embodiment of the present invention includes the lateral member (the busbar frame <NUM> in the present embodiment) disposed lateral to the substrate <NUM> and covering the side surface 510b of the substrate <NUM>. The lateral member incudes an opening <NUM> through which at least one of two portions, sandwiching the through hole <NUM>, in the through member (the busbar <NUM> in the present embodiment) that penetrates the through hole <NUM> of the substrate <NUM> can be visually recognized from the outside. In this manner, the opening <NUM> is formed in the lateral member, and at least one of the two portions of the through member, the two portions sandwiching the through hole <NUM> of the substrate <NUM>, is made visually recognizable from the outside. Thereby, the portion penetrating the through hole <NUM> of the through member can be visually recognized from the outside of the lateral member through the opening <NUM>, so that the state of penetration of the through member into the substrate <NUM> can be easily grasped. When the state of penetration of the through member into the substrate <NUM> can be easily grasped, it is possible to prevent a defect due to attachment failure or the like of the through member to the substrate <NUM>.

The opening <NUM> of the lateral member is formed such that a portion closer to the energy storage device <NUM> out of the two portions sandwiching the through hole <NUM> in the through member can be visually recognized. In the through member, a portion closer to the energy storage device <NUM> out of two portions sandwiching the through hole <NUM> is located inside the energy storage apparatus <NUM>, and it is thus difficult to grasp a state of the through member. Accordingly, the opening <NUM> is formed in the lateral member such that the portion close to the energy storage device <NUM> can be visually recognized. As a result, the portion of the through member closer to the energy storage device <NUM>, the portion being in a state of penetration difficult to grasp, can be visually recognized from the outside of the lateral member through the opening <NUM>, so that the state of penetration of the through member can be easily grasped.

The through member is the busbar <NUM> connected to the energy storage device <NUM>, and the opening <NUM> of the lateral member is formed such that the joined state of the protrusion <NUM>, which penetrates the through hole <NUM> of the busbar <NUM> and is joined to the substrate <NUM> to the substrate <NUM>, can be visually recognized. In the present embodiment, in order to measure the voltage of the energy storage device <NUM>, the protrusion <NUM> is formed on the busbar <NUM>, and the protrusion <NUM> is allowed to penetrate the through holes <NUM> of the substrate <NUM> and is joined (e.g., soldered) to the substrate <NUM>. In this case, it is necessary to check whether the protrusion <NUM> of the busbar <NUM> is joined to the substrate <NUM> (e.g., whether a solder fillet is formed favorably). Therefore, the opening <NUM> is formed in the lateral member, and the joined state of the protrusion <NUM> to the substrate <NUM> can be visually recognized. As a result, the joined state of the protrusion <NUM> of the busbar <NUM> to the substrate <NUM> can be easily grasped, so that it is possible to prevent stress concentration on the protrusion <NUM> due to joint failure and to prevent the breakage of the protrusion <NUM>.

The lateral member is the busbar frame <NUM> on which the busbar <NUM> is placed, and the busbar frame <NUM> includes the wall <NUM> that covers the side surface 510b of the substrate <NUM> and in which the opening <NUM> is formed. In the energy storage apparatus <NUM>, the busbar frame <NUM> may be provided with the wall <NUM> that covers the side surface 510b of the substrate <NUM>. In the present embodiment, for the purpose of preventing the movement (vibration) of the energy storage devices <NUM> in the outer case <NUM>, or some other purpose, for example, the wall <NUM> is formed on the busbar frame <NUM>, and the busbar frame <NUM> is fixed to the outer case <NUM> by being engaged with the outer case lid <NUM>. The wall <NUM> is provided on the busbar frame <NUM> as a guide for disposing the outer case lid <NUM> on the outer case body <NUM>. In such a case, there is a possibility that the state of penetration of the through member into the substrate <NUM> cannot be grasped due to the wall <NUM> of the busbar frame <NUM>. Therefore, the opening <NUM> is formed in the wall <NUM> of the busbar frame <NUM> to make the state of penetration of the through member into the substrate <NUM> visually recognizable. As a result, even when the wall <NUM> is provided in the busbar frame <NUM>, the state of penetration of the through member into the substrate <NUM> can be easily grasped.

Since the opening <NUM> comprises a notch formed in the lateral member, by forming the notch in the lateral member, it is possible to easily form the opening <NUM> through which the state of penetration of the through member into the substrate <NUM> can be visually recognized.

The opening <NUM> is disposed to face the long side surface 442a of the protrusion <NUM> of the through member. As described above, by disposing the opening <NUM> to face the long side surface 442a of the protrusion <NUM> instead of the short side surface 442b thereof, it is possible to visually recognize the long side surface 442a side of the protrusion <NUM> instead of the short side surface 442b side. This makes it easy to visually recognize the state of penetration of the through member, so that the state of penetration of the through member into the substrate <NUM> can be easily and more reliably grasped.

In the above description, the effect in the case where the busbar <NUM> is an example of the through member has been mainly described, but a similar effect is also obtained when each of the busbars <NUM> to <NUM> is an example of the through member.

Next, a first modification of the above embodiment will be described. <FIG> is a side view illustrating a state where the protrusion <NUM> of the busbar <NUM> according to the first modification of the present embodiment is joined to the substrate body <NUM> of the substrate <NUM>. Specifically, <FIG> is a diagram corresponding to <FIG>.

As illustrated in <FIG>, the busbar <NUM> in the present modification includes solder <NUM> and solder <NUM> instead of the solder <NUM> and the solder <NUM> in the above embodiment. The solder <NUM> has a shape in which the widths in the X-axis direction and the Y-axis direction sharply increase toward the Z-axis minus direction. The solder <NUM> has a shape in which the widths in the X-axis direction and the Y-axis direction sharply increase toward the Z-axis plus direction. Other configurations are the same as those of the above embodiment, and thus detailed description thereof is omitted.

As described above, according to the energy storage apparatus in the present modification, it is possible to achieve the same effects as in the above embodiment. That is, as described in the present modification, the shape of the solder <NUM> may be any shape and is not particularly limited. In general, as the shape of the solder fillet, the shape of the solder <NUM> and the solder <NUM> illustrated in the present modification is preferably used, and the effect of being able to grasp the shape by visually recognizing the shape is high.

Next, a second modification of the above embodiment will be described. <FIG> is a side view illustrating a configuration of an opening <NUM> formed in the wall <NUM> of the busbar frame <NUM> according to the second modification of the present embodiment. Specifically, <FIG> is a diagram corresponding to <FIG>.

As illustrated in <FIG>, in the busbar frame <NUM> according to the present modification, the opening <NUM> is formed in the wall <NUM> instead of the opening <NUM> in the above embodiment. Other configurations are the same as those of the above embodiment, and thus detailed description thereof is omitted.

The opening <NUM> is a rectangular through hole formed in the wall <NUM> and is disposed at a position facing the protrusion base end 442d of the protrusion <NUM> of the busbar <NUM> and the solder <NUM>. Hence the opening <NUM> is formed such that the state of the fillet of the solder <NUM> in the protrusion base end 442d can be visually recognized. That is, the opening <NUM> is formed such that a portion closer to the energy storage device <NUM> out of two portions of the busbar <NUM> sandwiching the through hole <NUM> can be visually recognized from the outside.

As described above, according to the energy storage apparatus in the present modification, it is possible to achieve the same effects as in the above embodiment. In particular, since the opening <NUM> is a through hole formed in the lateral member (busbar frame <NUM>), by forming the through hole in the lateral member, it is possible to easily form the opening <NUM> through which the state of penetration of the through member (busbar <NUM>) into the substrate <NUM> can be visually recognized. As described above, the solder <NUM> flows from the protrusion tip 442c side to the protrusion base end 442d side and is solidified at the time of application, and it is thus important to visually recognize the state of the fillet of the solder <NUM> on the protrusion base end 442d side so as to confirm whether the fillet of the solder <NUM> is formed favorably. Therefore, since the opening <NUM> is formed such that the state of the fillet of the solder <NUM> on the protrusion base end 442d side can be visually recognized, it is possible to effectively confirm whether the fillet of the solder <NUM> is formed favorably.

Although the energy storage apparatus according to the present embodiment and the modifications thereof have been described above, the present invention is not limited to the above embodiment and the modifications thereof. That is, the embodiment disclosed herein and the modifications thereof are illustrative in all respects and are not restrictive, and the scope of the present invention is indicated by the claims, and includes all changes within the meaning and scope equivalent to the claims.

In the above embodiment and the modifications thereof, the busbar <NUM> (busbars <NUM> to <NUM>) has been an example of the through member, but any member may be used as the through member so long as the member penetrates the substrate <NUM>. Examples of the through member include a terminal (connector) of a cable connected to the substrate <NUM>, a thermistor, other electronic components, and the like.

In the above embodiment and the modifications thereof, the busbar frame <NUM> has been an example of the lateral member, but any member may be used as the lateral member so long as the member covers the side surface of the substrate <NUM>. Examples of the lateral member include the sidewall of the outer case, a binding member (side plate, end plate) for binding the plurality of energy storage devices <NUM>, a spacer, and the like.

In the above embodiment and the modifications thereof, the busbar <NUM> has been joined to the substrate <NUM> by soldering, but a method for joining the busbar <NUM> to the substrate <NUM> is not limited to soldering. The busbar <NUM> may be joined to the substrate <NUM> by welding, screw fastening, caulking, or the like. Even in this case, the joined state of the busbar <NUM> to the substrate <NUM> can be visually recognized.

In the above embodiment and the first modification, the opening <NUM> has been formed such that both of the two portions of the busbar <NUM> sandwiching the through hole <NUM> can be visually recognized. However, the opening <NUM> may be formed such that only one of the two portions can be visually recognized. In the above second modification, the opening <NUM> may be formed such that a portion farther from the energy storage device <NUM> out of the two portions of the busbar <NUM> sandwiching the through hole <NUM> can be visually recognized, or may be formed such that both of the two portions can be visually recognized. The same applies to other openings.

In the above embodiment and the modifications thereof, the opening <NUM> (<NUM>) has been disposed to face the long side surface 442a of the protrusion <NUM> of the busbar <NUM>. However, the opening <NUM> (<NUM>) may be disposed to face the short side surface 442b of the protrusion <NUM>. Openings may be disposed so as to be visually recognizable from two directions, such as an opening in which the same protrusion <NUM> can be visually recognized from the long side surface 442a side and an opening in which the same protrusion can be visually recognized from the short side surface 442b side. The same applies to other openings.

In the above embodiment and the modifications thereof, the protrusion <NUM> of the busbar <NUM> has been a rectangular portion in a top view having the long side surfaces 442a and the short side surfaces 442b. However, the protrusion <NUM> may be a portion having any shape such as a square shape, a circular shape, an elliptical shape, or an oval shape in a top view. When the protrusion <NUM> has an elliptical shape, an oval shape, or the like in a top view, the opening <NUM> (<NUM>) is preferably disposed at a position facing the long side surface. The same applies to the other busbars.

In the above embodiment and the modifications thereof, any of the busbars <NUM> to <NUM> may not have the above configuration, or any of the openings <NUM>, <NUM>, <NUM>, <NUM> (<NUM>) may not have the above configuration.

Claim 1:
An energy storage apparatus (<NUM>) comprising:
an energy storage device (<NUM>);
a substrate (<NUM>) in which a through hole (<NUM>) penetrating a main surface (510a) is formed;
a through member (<NUM>) that penetrates the through hole (<NUM>); and
a lateral member (<NUM>) disposed lateral to the substrate (<NUM>) and covering a side surface (510b) of the substrate (<NUM>),
wherein the lateral member (<NUM>) is a busbar frame on which a busbar connected to the energy storage device (<NUM>) is mounted, and
wherein the busbar frame includes: a frame body (<NUM>), and a wall (<NUM>, <NUM>, <NUM>, <NUM>) that projects from the frame body (<NUM>) and covers the side surface (510b) of the substrate (<NUM>),
characterised in that
the lateral member (<NUM>) includes an opening (<NUM>) formed in said wall (<NUM>,<NUM>,<NUM>,<NUM>), through which at least one of two portions of the through member (<NUM>), the two portions sandwiching the through hole (<NUM>), is visually recognizable from an outside.