Energy storage apparatus, moving body, and energy storage system

An energy storage apparatus includes an energy storage device including a surface having a first end face from which an external terminal protrudes and a second end face on an opposite side from the first end face and a retaining member that includes paired end members disposed on opposite sides of the energy storage device in a second direction orthogonal to a first direction in which the external terminal protrudes and a coupling portion for coupling the paired end members. The coupling portion includes a main body portion facing the energy storage device in a third direction orthogonal to the first direction and the second direction, a first extending portion extending along the first end face from the main body portion, and an end extending portion extending along the end member from the main body portion, a drain portion is provided to a position of the energy storage apparatus near the second end face, and the main body portion, the first extending portion, and the end extending portion are connected to each other to thereby form a first end corner portion of the coupling portion.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is based on Japanese Patent Application No. 2017-153397, filed on Aug. 8, 2017, the entire contents of which are hereby incorporated by reference.

FIELD

The present invention relates to an energy storage apparatus including an energy storage device and a retaining member for retaining the energy storage device, a moving body including the energy storage apparatus, and an energy storage system including the energy storage apparatus.

BACKGROUND

Conventionally, there is a known battery block100including a battery stacked product102formed by stacking a plurality of battery cells101and a fixing member103for fastening the battery stacked product102in a stack direction as shown inFIGS. 14 and 15(see JP 2013-246990 A).

Each of the battery cells101includes a prismatic cover case1011with a bottom, a sealing plate1012for closing an opening portion of the cover case1011, and electrode terminals1013provided to opposite end portions of the sealing plate1012.

The fixing member103includes end plates104disposed at opposite ends of the battery stacked product102and coupling fixtures105fixed to the end plates104to fasten the battery stacked product102in the stack direction with end plates104interposed therebetween.

Each of the coupling fixtures105is extending in the stack direction of the battery stacked product102and has an L shape in cross-section. Specifically, each of the coupling fixtures105has a plate-shaped first portion1051along outer side faces101A of the battery cells101, a plate-shaped second portion1052along top faces101B or bottom faces101C of the battery cells101, and plate-shaped third portions1053along the end plates104. At each end portion of each of the coupling fixtures105in the stack direction, the plate-shaped first to third portions1051to1053are connected continuously (without leaving clearances therebetween), each of corner portions106of the coupling fixture105is formed. The coupling fixers105formed in this manner are fixed to the end plates104disposed at the opposite ends of the battery stacked product102to thereby fasten the battery stacked product102in the stack direction with the end plates104interposed therebetween.

In the above-described battery block100, because there are no clearances at the corner portions106of the coupling fixers105, water (condensed water or the like) is accumulated in the corner portions106positioned on a lower side depending on an attitude of the battery block100and the accumulated water may make the battery cells101and the fixing member103electrically continuous with each other in some cases when condensation or the like occurs on faces of the coupling fixtures105facing the battery cells101due to a change in a temperature around the battery block100or the like.

SUMMARY

An object of embodiments is to provide an energy storage apparatus in which water is less likely to be accumulated in a member for retaining energy storage devices, a moving body including the energy storage apparatuses, and an energy storage system including the energy storage apparatuses.

According to an aspect of embodiments, there is provided an energy storage apparatus including an energy storage device including a surface having a first end face from which an external terminal protrudes and a second end face on an opposite side from the first end face and a retaining member that includes paired end portions disposed on opposite sides of the energy storage device in a second direction orthogonal to a first direction in which the external terminal protrudes and a coupling portion for coupling the paired end portions and that retains the energy storage device, wherein the coupling portion includes a main body portion facing the energy storage device in a third direction orthogonal to the first direction and the second direction, a first extending portion extending along the first end face from the main body portion, and an end extending portion extending along the end portion from the main body portion, a drain portion is provided to a position of the energy storage apparatus near the second end face, and the main body portion, the first extending portion, and the end extending portion are continuously connected to each other to thereby form a first end corner portion of the coupling portion.

DESCRIPTION OF EMBODIMENTS

According to an aspect of embodiments, there is provided an energy storage apparatus including an energy storage device including a surface having a first end face from which an external terminal protrudes and a second end face on an opposite side from the first end face and a retaining member that includes paired end portions disposed on opposite sides of the energy storage device in a second direction orthogonal to a first direction in which the external terminal protrudes and a coupling portion for coupling the paired end portions and that retains the energy storage device, wherein the coupling portion includes a main body portion facing the energy storage device in a third direction orthogonal to the first direction and the second direction, a first extending portion extending along the first end face from the main body portion, and an end extending portion extending along the end portion from the main body portion, a drain portion is provided to a position of the energy storage apparatus near the second end face, and the main body portion, the first extending portion, and the end extending portion are continuously connected to each other to thereby form a first end corner portion of the coupling portion.

With this configuration, when the energy storage apparatus is disposed with the drain portion positioned at a lower end portion of the energy storage apparatus, water of condensation or the like occurring on each of the faces of the retaining member facing the energy storage device is drained outside through the drain portion and therefore the water is less likely to be accumulated in the retaining member.

The energy storage apparatus may further include an insulating member for covering at least a face of the coupling portion facing the energy storage device, wherein the coupling portion may have a second extending portion extending along the second end face from the main body portion, the insulating member may have a convex part positioned astride the main body portion and the second extending portion between each of the end portions and the energy storage device adjacent to the end portion, and the drain portion may be disposed on an outer side of the convex portion in the second direction.

With this configuration, even if the water remains undrained from an end portion in the second direction of the retaining member through the drain portion, the water is prevented by the convex part from flowing toward the energy storage device. As a result, it is possible to suppress electrical continuity between the retaining member and the energy storage device through the water.

In this case, in the energy storage apparatus, the first extending portion and the second extending portion may respectively and continuously extend from one of the end portions to the other end portion in the second direction and a dimension of the second extending portion may be larger than a dimension of the first extending portion in the third direction.

Because the dimension of the second extending portion is larger than the dimension of the first extending portion in the third direction in the retaining member in this manner, it is possible to prevent strength of a portion of the retaining member on a side of the second extending portion from becoming lower than a portion on a side of the first extending portion including the first end corner portion strength of which is secured by continuously connecting the portions in the three directions (the first extending portion, the main body portion, and the end extending portions or the end portions).

According to another aspect of embodiments, there is provided a moving body including: any of the above-described energy storage apparatuses; a moving body main body mounted with the energy storage apparatus; and a drive portion for driving the moving body main body by using electric power supplied from the energy storage apparatus, wherein the energy storage apparatus is disposed with the drain portion positioned at a lower end portion of the energy storage apparatus.

With this configuration, because the drain portion is disposed at the lower end portion of the energy storage apparatus mounted into the moving body, the water is less likely to be accumulated in the retaining member.

According to another aspect of embodiments, there is provided an energy storage system including: any of the above-described energy storage apparatuses; an energy storage system main body mounted with the energy storage apparatus; and an input/output terminal which is connected to the energy storage apparatus and through which electric power can be input from outside and output to the outside, wherein the energy storage apparatus is disposed with the drain portion positioned at a lower end portion of the energy storage apparatus.

With this configuration, because the drain portion is disposed at the lower end portion of the energy storage apparatus mounted into the energy storage system, the water is less likely to be accumulated in the retaining member.

As described above, according to the aspects of the embodiments, it is possible to provide the energy storage apparatus in which the water is less likely to be accumulated in the retaining member, the moving body including the energy storage apparatus, and the energy storage system including the energy storage apparatus.

A first embodiment of the present invention will be described below with reference toFIGS. 1 to 11. Names of respective component members (respective component elements) in the embodiment are the names in the embodiment and may be different from those of respective component members (respective component elements) in “BACKGROUND”.

As shown inFIGS. 1 to 4, an energy storage apparatus includes energy storage devices10, each of the energy storage devices10including a surface having a first end face13A from which external terminals14protrude and a second end face13B on an opposite side from the first end face13A, and a retaining member4for retaining the energy storage devices10. The energy storage apparatus1in the embodiment includes the plurality of energy storage devices10arranged in a predetermined direction (X-axis direction). The energy storage apparatus1includes a plurality of adjacent members2adjacent to the energy storage devices10, insulators (insulating members)6disposed between the retaining member4and the plurality of energy storage devices10, and bus bars8connected to the external terminals14of the energy storage devices10.

As the energy storage device10, there are a primary battery, a secondary battery, a capacitor, and the like. The energy storage device10in the embodiment is a chargeable and dischargeable nonaqueous electrolyte secondary battery. More specifically, the energy storage device10in the embodiment is a lithium ion secondary battery which uses electron transfer caused by transfer of lithium ions.

To put it concretely, each of the energy storage devices10includes an electrode assembly12, a case13for housing the electrode assembly12with electrolyte solution, the external terminals14at least parts of which are exposed to an outside of the case13, current collectors15each of which connects the electrode assembly12and each of the external terminals14, and an in-case insulating body16disposed between the electrode assembly12and the case13.

In the electrode assembly12, a positive electrode and a negative electrode are layered alternately with separators interposed therebetween. The electrode assembly12in the embodiment is what is called a wound electrode assembly formed by winding the long positive electrode and the long negative electrode layered alternately with the separators interposed therebetween. Energy storage device10is charged and discharged by movements of lithium ions between the positive electrode and the negative electrode in the electrode assembly12.

The case13includes a case main body131having an opening and a lid plate132for closing the opening of the case main body131. The case main body131in the embodiment has a prismatic cylindrical shape with a bottom and the case13has a rectangular parallelepiped shape (hexahedral shape). The case13has the flat rectangular parallelepiped shape and the plurality of energy storage devices10are arranged in an X-axis direction with wide faces of the cases13facing each other.

In the following description, the face (outer face of the lid plate132) from which the external terminals14protrude is also referred to as the first end face13A, the end face of the hexahedral case13on an opposite side from the first end face13A is also referred to as the second end face13B, opposite end faces facing the adjacent energy storage devices10are also referred to as third end faces13C, and opposite end faces in a direction (Y-axis direction) orthogonal to directions of the normals to the first end face13A and the second end face13B (Z-axis direction) and the X-axis direction are also referred to as fourth end faces13D.

Each of the adjacent members2is disposed between the energy storage devices10arranged in the X-axis direction or between the energy storage device10and a member (a part of the retaining member4in an example in the embodiment) disposed side by side with the energy storage device10in the X-axis direction. The adjacent members2include a plurality of kinds of adjacent members. The adjacent members2in the embodiment include the first adjacent members21each of which is disposed between the adjacent energy storage devices10and the second adjacent members22each of which is disposed on an outer side of the energy storage device10at the very end in the X-axis direction.

Each of the first adjacent members21has an insulation property and is disposed between the adjacent energy storage devices10to thereby secure a clearance (creepage distance or the like) between the energy storage devices10. Specifically, each of the first adjacent members21includes a first main body portion211adjacent to the energy storage devices10(case main bodies131) and first restricting portions212for restricting movements of the energy storage devices10with respect to the first main body portion211.

The first main body portion211is a portion facing the third end faces13C of the energy storage devices10and spreading in a direction of a Y-Z plane (plane including the Y axis and the Z axis). The first main body portion211in the embodiment forms a flow path through which fluid (air in the example in the embodiment) for temperature adjustment can flow between the adjacent energy storage devices10and the first main body portion211.

The first restricting portions212extend in the X-axis direction from the first main body portion211and come in contact with the energy storage devices10(specifically, the cases13), adjacent to the first main body portion211, from outside in the direction of the Y-Z plane to thereby restrict the movements of the energy storage devices10in the direction of the Y-Z plane with respect to the first main body portion211.

Each of the second adjacent members22has an insulation property and is disposed between the energy storage device10and the retaining member4(end member41) in the X-axis direction to thereby secure a clearance (creepage distance or the like) between the energy storage device10and the retaining member4(end member41). Specifically, each of the second adjacent members22includes a second main body portion221adjacent to the energy storage device10between the energy storage device10and the retaining member4and second restricting portions222for restricting a movement of the energy storage device10with respect to the second main body portion221.

The second main body portion221is a portion facing the third end face13C of the energy storage device10and spreading in the direction of the Y-Z plane. The second main body portion221in the embodiment forms a flow path through which the fluid (air in the example in the embodiment) for the temperature adjustment can flow between the adjacent energy storage device10and the second main body portion221.

The second restricting portions222extend in the X-axis direction from the second main body portion221and come in contact with the energy storage device10(specifically, the case13), adjacent to the second main body portion221, from outside in the direction of the Y-Z plane to thereby restrict the movement of the energy storage device10in the direction of the Y-Z plane with respect to the second main body portion221.

The retaining member4surrounds peripheries of the plurality of energy storage devices10and the plurality of adjacent members2to thereby retain the plurality of energy storage devices10and the plurality of adjacent members2in a block. The retaining member4is formed by a member made of metal or the like having conductivity. Specifically, the retaining member4includes the paired end members (end portions)41disposed on opposite sides of the energy storage devices10in the X-axis direction and coupling members (coupling portions)42for coupling the paired end members41.

Each of the paired end members41is disposed so that the second adjacent member22is sandwiched between the energy storage device10disposed at the end in the X-axis direction and the end member41. The end members41are spreading in the direction of the Y-Z plane. Specifically, each of the end members41includes a main body411having an outline (rectangular outline in the embodiment) corresponding to the energy storage device10and a pressing portion412protruding from the main body411toward the second main body portion221of the second adjacent member22to come in contact with and press the second adjacent member22.

The paired coupling members42are disposed on opposite sides of the plurality of energy storage devices10in the Y-axis direction. As also shown inFIGS. 5 and 6, each of the paired coupling members42includes a main body portion420facing the energy storage devices10in the Y-axis direction, a first extending portion421extending along the first end faces13A of the energy storage devices10from the main body portion420, end extending portions423extending along the end members41from the main body portion420, and drain portions426A provided to portions of the coupling member42near the second end faces13B of the energy storage devices10. Each of the paired coupling members42includes a second extending portion422extending along the second end faces13B of the energy storage device10from the main body portion420. The main body portion420, the first extending portion421, and the end extending portions423are continuously connected to each other to thereby form first end corner portions425of the coupling member42. In other words, each of the first end corner portions425is a portion where the main body portion420, the first extending portion421, and the end extending portion423are continuously connected. The main body portion420, the second extending portion422, and the end extending portions423form second end corner portions426of the coupling member42. In other words, each of the second end corner portions426is a portion where the main body portion420, the second extending portion422, and the end extending portion423are continuously connected or close to each other. At each of the second end corner portions426in the embodiment, the main body portion420and the second extending portion422are continuously connected to each other, the main body portion420and the end extending portion423are continuously connected to each other, and the second extending portion422and the end extending portion423are close to each other (specifically, a slit-shaped clearance is left between an end portion in the X-axis direction of the second extending portion and an end portion in the Z-axis direction of the end extending portion423). The first end corner portions425and the second end corner portions426are the portions for retaining corner portions of the cases13of the energy storage devices10disposed on outermost sides in the X-axis direction. Each of the second end corner portions426in the embodiment has the above-described drain portion426A.

The main body portion420is a plate-shaped portion facing, in the Y-axis direction, the plurality of energy storage devices10(specifically, the respective fourth end faces13D) arranged in the X-axis direction. The main body portion420in the embodiment is in a plate shape along an X-Z plane (plane including the X axis and the Z axis) and a rectangular shape long in the X-axis direction. The main body portion420includes paired beam portions4201extending in the X-axis direction and disposed at an interval in the Z-axis direction, paired first connecting portions4202extending in the Z-axis direction and connecting end portions of the paired beam portions4201, and second connecting portions4203extending in the Z-axis direction and connecting the paired beam portions4201at midway positions in the X-axis direction (positions overlapping, when seen in the Y-direction, the energy storage devices10disposed at the midway positions out of the plurality of energy storage devices10arranged in the X-axis direction in the embodiment).

One of the paired beam portions4201extends in the X-axis direction along end portions of the fourth end faces13D near the first end faces13A of the respective energy storage devices10. The other of the paired beam portions4201extends in the X-axis direction along end portions of the fourth end faces13D near the second end faces13B of the respective energy storage devices10. The plurality of second connecting portions4203in the embodiment are arranged at intervals in the X-axis direction.

The first extending portion421is the plate-shaped portion extending along the first end faces13A of the respective energy storage devices10from the main body portion420(specifically, the beam portion4201) and extending from one of the end members41to the other end member41. The first extending portion421in the embodiment extends in the Y-axis direction from an end portion (an upper end inFIG. 5) of the main body portion420near the first end faces13A and extends continuously from one of the end members41to the other end member41in the X-axis direction.

The second extending portion422is the plate-shaped portion extending along the second end faces13B of the respective energy storage devices10from the main body portion420(specifically, the beam portion4201) and extending from one of the end members41to the other end member41. The second extending portion422in the embodiment extends in the Y-axis direction from an end portion (a lower end inFIG. 5) of the main body portion420near the second end faces13B and extends continuously from one of the end members41to the other end member41in the X-axis direction. The second extending portion422has a larger dimension than the first extending portion421in the Y-axis direction.

The end extending portions423are the plate-shaped portions extending along the end members41from the main body portion420(specifically, the first connecting portions4202). The end extending portions423are the portions of the coupling member42that are fixed to the end members41to thereby connect the end members41and the coupling members42. The end extending portions423in the embodiment are fastened to the end members41by use of screws B. The end extending portions423extend in the Y-axis direction from end portions (left and right ends inFIG. 5) in the X-axis direction of the main body portion420. Each of the end extending portions423in the embodiment extends from one end portion (near the first end face13A) to a position near the other end portion (near the second end face13B) of the main body portion420in the Z-axis direction.

Each of the first end corner portions425is formed by continuously connecting (connecting) a corner portion of the main body portion420near the first end face13A, an end portion of the first extending portion421in the X-axis direction, and an end portion of the end extending portion423in the Z-axis direction to each other without leaving clearances therebetween. The first end corner portions425in the embodiment are formed by drawing, pressing, or the like. The first end corner portions425in the embodiment form corner portions of the energy storage apparatus1near the first end faces13A as well.

Each of the second end corner portions426is formed by a corner portion of the main body portion420near the second end face13B, an end portion of the second extending portion422in the X-axis direction, and an end portion of the end extending portion423in the Z-axis direction. The second end corner portions426in the embodiment form corner portions of the energy storage apparatus1near the second end faces13B as well. Each of the second end corner portions426has the drain portion426A between the second extending portion422and the end extending portion423.

Each of the drain portions426A is a clearance formed between the second extending portion422and the end extending portion423. Each of the drain portions426A in the embodiment is a small clearance (of about 3 to 6 mm), through which water can barely pass, so as to secure strength of the retaining member4. Through the clearances (drain portions426A), it is possible to drain water inside the second end corner portions426(on the side of the energy storage devices10) to the outside. Each of the drain portions426A in the embodiment is the clearance extending in the Y-axis direction, closed at one end with the main body portion420, and open at the other end in the Y-axis direction. The drain portions426A are formed by bending a plate member having a predetermined shape in order to form the second end corner portions426.

Each of the insulators6has an insulation property and disposed between each of the coupling members42and the plurality of energy storage devices10arranged in the X-axis direction. The insulator6covers at least a face (area) of the coupling member42facing the energy storage devices10. In this way, the insulators6insulate the retaining member4and the plurality of energy storage devices10arranged in the X-axis direction from each other. To put it concretely, as also shown inFIG. 7, each of the insulators6includes a main body cover portion60for covering the main body portion420, a first cover portion61for covering the first extending portion421, and a second cover portion62for covering the second extending portion422.

The main body cover portion60covers the face (hereinafter also referred to as “main body facing face”) of the main body portion420facing the energy storage devices10(specifically, the fourth end faces13D). The main body cover portion60has a shape corresponding to the main body portion420. In other words, the main body cover portion60includes paired beam portion cover portions600for covering faces of the beam portions4201facing the energy storage devices10, paired first connection cover portions601for covering faces of the first connecting portions4202facing the energy storage devices10, and a plurality of second connection cover portions602for covering faces of the second connecting portions4203facing the end members41.

The first cover portion61covers at least a face (area) of the first extending portion421facing the energy storage devices10. The first cover portion61in the embodiment covers both of the face of the first extending portion421facing the energy storage devices10(first end faces13A) and a face of the first extending portion421on an opposite side from the energy storage devices10.

As also shown inFIG. 8, the second cover portion62extends from a boundary position between the second extending portion422and the main body portion420to a tip end (tip end in the Y-axis direction) of the second extending portion422along a face422A of the second extending portion422facing the energy storage devices10(second end faces13B), is folded back at the tip end, and extends along a face (outer face)422B of the second extending portion422on an opposite side from the energy storage devices10. In other words, the second cover portion62includes a first portion621for covering the face of the second extending portion422facing the second end faces13B, a second portion622for covering the tip end of the second extending portion422, and a third portion623for covering the outer face of the second extending portion422.

The first portion621is the plate-shaped portion of the second cover portion62spreading along the facing face422A of the second extending portion422. To put it concretely, the first portion621is in a shape of a rectangle of size corresponding to the second extending portion422. The second portion622is the portion of the second cover portion62folded back from a tip end (end edge in the Y-axis direction) of the first portion621to cover the tip end of the second extending portion422. The third portion623is the plate-shaped portion of the second cover portion62spreading along the outer face422B of the second extending portion422. To put it concretely, the third portion623is the rectangular plate-shaped portion. The third portion623has a smaller dimension than the second extending portion422in the Y-axis direction.

In the above-described second cover portion62, at each of the opposite ends in the X-axis direction, a clearance between the first portion621and the third portion623is closed. As a result, the tip end portion (tip end portion in the Y-axis direction) of the second cover portion62is formed in a bag shape into which the tip end portion of the second extending portion422is inserted.

As also shown inFIGS. 9 to 11, each of the insulators6has a convex part65positioned astride the main body portion420and the second extending portion422between each of the end members41and the energy storage device10adjacent to the end member41. In the energy storage apparatus1in the embodiment, each of the convex parts65is disposed on an inner side of the drain portion426A in the X-axis direction. In other words, each of the drain portions426A is disposed on an outer side of the convex part65in the X-axis direction.

To put it concretely, each of the convex parts65protrudes from the first portion621of the second cover portion62and extends from a midway position of the first portion621in the Y-axis direction to the main body cover portion60. Each of the convex parts65in the embodiment has a thin plate shape (plate shape along the Y-Z plane) extending in the Y-axis direction from the main body portion420. An amount of protrusion (height from the first portion621) of each of the convex parts65is set to such an amount as to be able to prevent movement of water, which remains undrained from the second end corner portion426through the drain portion426A, toward the energy storage devices10.

Each of the bus bars8is the plate-shaped member made of metal or the like having conductivity. Each of the bus bars8makes the external terminals14of the different energy storage devices10electrically continuous with each other. The plurality of bus bars8(the corresponding number of bus bars8to the plurality of energy storage devices10) are provided to the energy storage apparatus1. The plurality of bus bars8in the embodiment connect all of the plurality of energy storage devices10included in the energy storage apparatus1in series (i.e., make the energy storage devices10electrically continuous with each other).

According to the above-described energy storage apparatus1, when the energy storage apparatus1is disposed so that the second end corner portions426are at lower positions than the other portions, water of condensation or the like occurring on each of the faces of the retaining member4facing the energy storage devices10may gather into the corner portions (second end corner portions)426of the retaining member4. Even in this case, the water is drained outside through the drain portions426A and therefore the water is less likely to be accumulated in the corner portions (second end corner portions)426.

In the energy storage apparatus1in the embodiment, each of the insulators6has the convex parts65each of which is positioned astride the main body portion420and the second extending portion422between each of the end members41and the energy storage device10adjacent to the end member41. Therefore, even if the water remains undrained from each of the second end corner portions426through the drain portion426A, the water is prevented by the convex part65from flowing toward the energy storage devices10. As a result, it is possible to effectively prevent the electrical continuity between the retaining member4and the energy storage devices10through the water.

In the energy storage apparatus1in the embodiment, the first extending portion421and the second extending portion422respectively and continuously extend from one of the end members41to the other end member41in the X-axis direction. In the energy storage apparatus1, the second extending portion422has the larger dimension than the first extending portion421in the Y-axis direction. In this way, in the retaining member4, even if strength of each of the second end corner portions426is reduced by the provision of the drain portion426A to the second end corner portion426, it is possible to make the dimension of the second extending portion422larger than the dimension of the first extending portion421in the Y-axis direction to thereby prevent strength of the portion of the retaining member4on the side of the second extending portion422from becoming lower than strength of the portion of the retaining member4on the side of the first extending portion421including the first end corner portion425the strength of which is secured by continuously connecting the portions in the three directions (the first extending portion421, the main body portion420, and the end extending portion423).

Next, a second embodiment of the present invention will be described with referent toFIG. 12. Configurations similar to those in the above-described first embodiment will be provided with the identical reference signs and will not be repeatedly described in detail and only different configurations will be described in detail. The second embodiment of the present invention is a moving body.

The moving body700includes energy storage apparatuses1, a moving body main body701mounted with the energy storage apparatuses1, and a drive portion702for driving the moving body main body701by use of electric power supplied from the energy storage apparatuses1. The moving body700in the embodiment is an automobile, the moving body main body701is a vehicle body, and the drive portion702is a motor. The moving body700is not limited to the automobile and may be an aircraft, a ship, a railroad vehicle, a construction machine, or the like. In other words, the moving body700may be anything that moves (travels) by using electric power supplied from the energy storage apparatus1.

In the moving body700, the energy storage apparatuses1are disposed with drain portions426A positioned at lower end portions of the energy storage apparatuses1. In an example shown inFIG. 12, the energy storage apparatuses1are disposed in such attitudes that the external terminals14of each of the energy storage devices10protrude upward from the first end face13A, i.e., the respective drain portions426A provided at the four corners near the second extending portions422of each of the energy storage apparatuses1are positioned at the lower end portion of the energy storage apparatus1. However, it is at least one of the drain portions426A provided to the respective four corners near the second extending portions422of each of the energy storage apparatuses1that needs to be positioned at the lower end portion of the energy storage apparatus1.

In the moving body700in the embodiment, the plurality of energy storage apparatuses1are mounted in the same attitudes into the moving body main body701.

According to the above-described moving body700, even if water of condensation or the like occurring on each of faces of a retaining member4facing the energy storage devices10gathers into corner portions (second end corner portions)426of the retaining member4in each of the energy storage apparatuses1mounted into the moving body700, the water is drained outside through the drain portions426A and therefore the water is less likely to be accumulated in the corner portions (second end corner portions)426.

Next, a third embodiment of the present invention will be described with referent toFIG. 13. Configurations similar to those in the above-described first embodiment will be provided with the identical reference signs and will not be repeatedly described in detail and only different configurations will be described in detail. The third embodiment of the present invention is an energy storage system.

The energy storage system800includes energy storage apparatuses1, an energy storage system main body801mounted with the energy storage apparatuses1, and input/output terminals802which are connected to the energy storage apparatuses1(specifically, all terminals of the energy storage apparatuses1) and through which electric power can be input from outside and output to the outside. The energy storage system800in the embodiment is used for wind power generation, solar power generation, or the like, the energy storage system main body801is a housing installed at an installation site G, and the input/output terminals802are the terminals connected to a wind turbine, a solar cell, a power transmission system for electric power transmission to the outside, or the like. The energy storage system800is not limited to the system for storing electric power generated by the wind turbine or the solar cell and may be a home system for storing inexpensive night-time electric power, a backup system for constantly storing a certain amount of electric power in case of disasters, or the like.

In the energy storage system800, the energy storage apparatuses1are disposed with drain portions426A positioned at lower end portions of the energy storage apparatuses1. In an example shown inFIG. 13, the energy storage apparatuses1are disposed in such attitudes that external terminals14of each of energy storage devices10protrude upward from a first end face13A, i.e., the respective drain portions426A provided at four corners near second extending portions422of each of the energy storage apparatuses1are positioned at the lower end portion of the energy storage apparatus1. However, it is at least one of the drain portions426A provided to the respective four corners near the second extending portions422of each of the energy storage apparatuses1that needs to be positioned at the lower end portion of the energy storage apparatus1.

In the energy storage system800in the embodiment, the plurality of energy storage apparatuses1are mounted in the same attitudes into the energy storage system main body801.

According to the above-described energy storage system800, even if water of condensation or the like occurring on each of faces of a retaining member4facing the energy storage devices10gathers into corner portions (second end corner portions)426of the retaining member4in each of the energy storage apparatuses1disposed in the energy storage system800, the water is drained outside through the drain portions426A and therefore the water is less likely to be accumulated in the corner portions (second end corner portions)426.

Needless to say, the energy storage apparatus, the moving body, and the energy storage system according to the present invention are not limited to the above-described embodiments and various changes can be made without departing from the gist of the present invention. For example, to a configuration of one of the embodiments, a configuration of another of the embodiments may be added. A part of a configuration of one of the embodiments may be replaced with a configuration of another of the embodiments. Furthermore, a part of a configuration of one of the embodiments may be eliminated.

Although the corner portions (second end corner portions)426provided with the drain portions426A are disposed at the coupling members42in the energy storage apparatus1in each of the above-described embodiments, the present invention is not limited to this configuration. For example, corner portions (second end corner portions)426provided with drain portions426A may be disposed at a retaining member4, i.e., the corner portions426provided with the drain portions426A may be formed astride coupling members42and end members (end portions)41or formed at the end members (end portions)41. For example, to put it concretely, in the retaining member4, each of first end corner portions425may be formed by continuously connecting each of main body portions420, each of first extending portions421, and each of end members (end portions)41and each of second end corner portions426may be formed by each of the main body portions420, each of the second extending portions422, and each of the end members (end portions)41.

According to this configuration, similarly to the energy storage apparatus1in each of the above-described embodiments, when the energy storage apparatus1is disposed so that the second end corner portions426are at lower positions than the other portions, water of condensation or the like occurring on each of faces of the retaining member4facing energy storage devices10may gather into the corner portions (second end corner portions)426of the retaining member4. Even in this case, the water is drained outside through the drain portions426A. Therefore, the water is less likely to be accumulated in the corner portions (second end corner portions)426.

Although the paired beam portions4201of each of the coupling members42are connected by the first and second connecting portions4202,4203in the energy storage apparatus1in each of the above-described embodiments, the present invention is not limited to this configuration. For example, each of main body portions420may have paired beam portions4201only, i.e., the paired beam portions4201may be independent of each other. In this case, first end corner portions425are provided to the beam portion4201disposed near first end faces13A and second end corner portions426having drain portions426A are provided to the beam portion4201disposed near the second end faces13B (for example, the drain portions426A are provided to the configuration shown inFIG. 13).

Although the drain portions426A provided to the second end corner portions426are the clearances formed by bending the plate-shaped portions in the energy storage apparatus1in each of the above-described embodiments, the present invention is not limited to this configuration. For example, the drain portions426A may be notches, holes, slits, or the like. In other words, the drain portions426A only have to have such configurations (shapes) as to be able to drain the water inside the second end corner portions426(on the side of the energy storage devices10) to the outside.

Although each of the coupling members42includes the main body portion420, the first extending portion421, the second extending portion422, and the end extending portions423in the energy storage apparatus1in each of the above-described embodiments, the present invention is not limited to this configuration. Each of the coupling members42only has to include at least the main body portion420, the first extending portion421, and portions of the end extending portions423forming the first end corner portions425(only upper end portions of the end extending portions423inFIG. 1). In other words, each of the coupling members42does not have to include the second extending portion422and end portions of the end extending portions423near the second extending portion422.

Although the main body portion420of each of the coupling members42is disposed in a range in the Z-axis direction from an end portion of the fourth end face13D near the first end face13A of each of the energy storage devices10to an end portion of the fourth end face13D near the second end face13B in the energy storage apparatus1in each of the above-described embodiments, the present invention is not limited to this configuration. The main body portion420only has to be disposed in such a range in the Z-axis direction as to be able to form the first end corner portions425. In other words, the main body portion420only has to include at least a portion extending in the X-axis direction along end portions of the fourth end faces13D near the first end faces13A of the respective energy storage devices10.

Although the drain portions426A are provided to the end portions in the X-axis direction of the portion of each of the coupling members42on the side of the second extending portion422in the energy storage apparatus1in each of the above-described embodiments, the present invention is not limited to this configuration. The drain portions426A may be disposed at midway positions in the X-axis direction of the portion of each of the coupling members42on the side of the second extending portion422. In this case, at each of the second end corner portions426, the main body portion420, the second extending portion422, and the end extending portion423may be continuously connected to each other without leaving clearances. The drain portion426A may be disposed throughout an entire area in the X-axis direction or the Y-axis direction of the end portion of each of the coupling members42on the side of the second extending portion422.

Although each of the energy storage devices is used as the chargeable and dischargeable nonaqueous electrolyte secondary battery (e.g., lithium ion secondary battery) in the case described in each of the above-described embodiments, the energy storage device is of any type and size (capacity). Although the lithium ion secondary battery has been described as an example of the energy storage device in each of the above-described embodiments, the energy storage device is not limited to the lithium ion secondary battery. For example, the present invention can be applied to various secondary batteries, primary batteries, and an energy storage device of a capacitor such as an electric double layer capacitor.