Electricity storage device

Abstract

A power storage device is provided with a power storage unit and an exterior body that accommodates the power storage unit. The power storage unit includes: a plurality of power storage elements arranged in a predetermined direction; and a first holding member that is adjacent to the plurality of power storage elements in a given direction and holds the plurality of power storage elements. The first holding member is joined to the exterior body.

Description

Technical Field

[0001] The present invention relates to an electric storage device. Background Art

[0002] Patent Document 1 discloses a power storage system in which a power storage unit in which a plurality of bag-type capacitor cells are assembled into a frame and then unitized is accommodated in a casing.

[0003] Prior Art Literature

[0004] Patent Literature

[0005] Patent Document 1: Japanese Patent Application Publication No. 2007-110035 Summary of the invention

[0006] Problems to be solved by the invention

[0007] Here, if the power storage unit moves in the casing, the power storage unit may hit the casing, causing damage.

[0008] The present invention was completed by the inventors of the present application with new attention paid to the above-mentioned problems, and an object of the present invention is to improve the vibration resistance or impact resistance of an electric storage device.

[0009] Means for solving problems

[0010] A power storage device according to one embodiment of the present invention comprises: a power storage unit; and an outer casing that accommodates the power storage unit, wherein the power storage unit has: a plurality of power storage elements arranged in a given direction; and a first retaining member that is adjacent to the plurality of power storage elements in the given direction and retains the plurality of power storage elements, the first retaining member being joined to the outer casing.

[0011] Effects of the Invention

[0012] According to the present invention, the vibration resistance or impact resistance of the power storage device can be improved. BRIEF DESCRIPTION OF THE DRAWINGS

[0013] Figure 1 It is a perspective view showing the appearance of the power storage device according to the embodiment.

[0014] Figure 2 It is an exploded perspective view showing each component when the power storage device according to the embodiment is disassembled.

[0015] Figure 3 It is a cross-sectional perspective view showing a joining structure between an exterior body and a power storage cell according to an embodiment.

[0016] Figure 4 It is a cross-sectional perspective view showing a joining structure between an exterior body and an electric storage cell according to Modification 1. DETAILED DESCRIPTION

[0017] (1) An electric storage device according to one embodiment of the present invention comprises: an electric storage unit; and an outer casing that accommodates the electric storage unit, wherein the electric storage unit has: a plurality of electric storage elements arranged in a given direction; and a first retaining member that is adjacent to the plurality of electric storage elements in the given direction and retains the plurality of electric storage elements, the first retaining member being joined to the outer casing.

[0018] According to the power storage device involved in one aspect of the present invention, since the first retaining member provided at the end of the power storage unit is engaged with the outer casing, the power storage unit is fixed at least on one side in the outer casing. As a result, the power storage unit becomes stable in the outer casing. Therefore, the vibration resistance or impact resistance of the power storage device can be improved.

[0019] (2) In the power storage device described in (1) above, the exterior body may include: an exterior body main body having an opening at one end in the given direction; and an exterior body cover body attached to the one end of the exterior body main body and closing the opening.

[0020] According to the power storage device described in (2) above, since the power storage unit is accommodated in the outer casing body that is open at one end in a given direction, when the first retaining member is arranged at the other end of the power storage unit in the given direction, the first retaining member can be joined to the bottom of the outer casing body. That is, when the power storage unit is accommodated in the outer casing body, the first retaining member arranged at the other end of the power storage unit can be joined to the outer casing body. On the other hand, when the first retaining member is arranged at one end of the power storage unit in the given direction, the first retaining member can be joined to the outer casing cover. That is, when the outer casing cover is installed on one end of the outer casing body, the first retaining member arranged at one end of the power storage unit can be joined to the outer casing cover. In this way, the first retaining member provided at the end of the power storage unit can be smoothly joined to the outer casing.

[0021] (3) In the power storage device described in (1) or (2) above, the power storage unit may further include a second retaining member for retaining the plurality of power storage elements, the second retaining member being arranged at a position for sandwiching the plurality of power storage elements together with the first retaining member in the given direction, and being joined to the outer casing.

[0022] According to the power storage device described in (3) above, since the plurality of power storage elements are held by being sandwiched between the first holding member and the second holding member, the plurality of power storage elements are further stabilized in the outer casing by the first holding member and the second holding member. Furthermore, since the first holding member is joined to the outer casing and the second holding member is joined to the outer casing, the power storage unit is fixed on both sides in the outer casing. Thus, the vibration resistance or impact resistance of the power storage device can be further improved.

[0023] (4) In the power storage device described in (3) above, a gap may be formed between at least one of the first holding member and the second holding member and the exterior body at a position corresponding to the plurality of power storage elements.

[0024] According to the power storage device described in (4) above, since a gap is formed between at least one of the first retaining member and the second retaining member and the outer casing at a position corresponding to the plurality of power storage elements, the expansion of the plurality of power storage elements can be absorbed by the gap. Therefore, deformation of the outer casing caused by the expansion of the plurality of power storage elements can be suppressed.

[0025] (5) In the power storage device described in (4) above, a circuit board may be arranged in the gap.

[0026] According to the power storage device described in (5), since the circuit substrate is arranged in the gap between at least one of the first holding member and the second holding member and the outer casing, the circuit substrate can be accommodated even without providing a dedicated member covering the circuit substrate. If a dedicated member is not required, the weight can be reduced, thereby further improving the vibration resistance or impact resistance. Furthermore, if a dedicated member is not required, space saving can be achieved in the outer casing, and the power storage device can be miniaturized.

[0027] (Implementation Method)

[0028] Hereinafter, the power storage device involved in the embodiments of the present invention (including its modified examples) will be described with reference to the accompanying drawings. The embodiments described below are all general or specific examples. The numerical values, shapes, materials, components, configuration positions of components, and connection methods shown in the following embodiments are examples, and their purpose is not to limit the present invention. In each figure, the dimensions and the like are not strictly illustrated.

[0029] In the following description and drawings, the arrangement direction of the outer casing body and the outer casing cover in the outer casing of the storage device, or the arrangement direction of the plurality of storage elements provided in the storage device is defined as the X-axis direction. The protruding direction of each lead terminal of the storage element is defined as the Y-axis direction. The arrangement direction or the up-down direction of a pair of lead terminals provided in the storage element is defined as the Z-axis direction. The X-axis direction is an example of a given direction. These X-axis directions, Y-axis directions, and Z-axis directions are directions that intersect each other (orthogonal in the following embodiments and their variations). In addition, depending on the usage, the case where the Z-axis direction does not become the up-down direction is also considered, but for the convenience of explanation below, the Z-axis direction is set as the up-down direction for explanation. In the following description, the so-called positive direction of the X-axis indicates the arrow direction side of the X-axis, and the so-called negative direction of the X-axis indicates the side opposite to the positive direction of the X-axis. The same is true for the Y-axis direction and the Z-axis direction. Regarding expressions such as parallel and orthogonal that indicate relative directions or postures, strictly speaking, they also include situations where they are not the directions or postures. The two directions being orthogonal not only means that the two directions are completely orthogonal, but also means that they are substantially orthogonal, that is, they include a difference of several %. In the following description, when "insulation" is expressed, it means "electrical insulation".

[0030] [Overall Description of the Power Storage Device]

[0031] use Figure 1 as well as Figure 2 Next, an overall description of the power storage device 1 according to the embodiment will be given. Figure 1 It is a perspective view showing the appearance of the power storage device 1 according to the embodiment. Figure 2 It is an exploded perspective view showing each component when the power storage device 1 according to the embodiment is disassembled.

[0032] The power storage device 1 is a device that can be charged with electricity from the outside and can discharge electricity to the outside. In the present embodiment, it has a roughly rectangular parallelepiped shape. The power storage device 1 is a battery module (battery pack) used for power storage purposes or power supply purposes. Specifically, the power storage device 1 is used as a battery for driving or starting the engine of a mobile body such as a car, a motor two-wheeled vehicle, a water vehicle, a ship, a snowmobile, an agricultural machine, a construction machine, and a railway vehicle for an electric railway. As the above-mentioned car, an electric car (EV), a hybrid electric car (HEV), a plug-in hybrid electric car (PHEV) and a fossil fuel (gasoline, light oil, liquefied natural gas, etc.) car can be exemplified. As the above-mentioned railway vehicle for an electric railway, a tram, a monorail, a linear electric locomotive and a hybrid tram with both a diesel engine and an electric motor can be exemplified. In addition, the power storage device 1 can also be used as a battery for fixed installations such as for home or commercial use.

[0033] like Figure 1 as well as Figure 2 As shown, the power storage device 1 includes a power storage cell 20 and an exterior body 10 that accommodates the power storage cell 20. The exterior body 10 includes an exterior body main body 11 that accommodates the power storage cell 20 and an exterior body cover 12 that closes the exterior body main body 11.

[0034] The exterior body 10 is a rectangular (box-shaped) container (module case) constituting the exterior body of the power storage device 1. Specifically, the exterior body 10 is a member that fixes the power storage cells 20 and the like at predetermined positions and protects these elements from impacts and the like.

[0035] The outer casing body 11 is a bottomed rectangular cylindrical member opened in the positive direction of the X-axis, and the open portion is an opening 111. The opening 111 is a substantially quadrilateral shape in a plan view (viewed in the X-axis direction). In the opening 111 of the outer casing body 11, in addition to the storage cell 20, a plurality of bus bars (not shown) and fuses (not shown) held in the storage cell 20 are accommodated.

[0036] The outer body cover 12 is a member that blocks the opening 111 of the outer body main body 11, and is joined to the outer body main body 11 in a state where the opening 111 of the outer body main body 11 is blocked from the positive direction of the X axis. A circuit substrate 35 is arranged at a position corresponding to the outer body cover 12 outside the opening 111. That is, the circuit substrate 35 is accommodated between the outer body main body 11 and the outer body cover 12. The outer body cover 12 has a pair of (positive and negative) external terminals 81. The external terminals 81 are electrically connected to the plurality of storage elements 21 included in the storage unit 20 via each bus bar, fuse, and circuit substrate 35. The storage device 1 is charged with electricity from the outside via the external terminal 81, and discharges electricity to the outside. The external terminal 81 is formed of a conductive member made of a metal such as a copper alloy such as brass, copper, aluminum, or an aluminum alloy.

[0037] Each bus bar is a plate-shaped member that electrically connects the external terminal 81 and the power storage element 21. Each bus bar is formed of a conductive member made of a metal such as copper, copper alloy, aluminum, or aluminum alloy.

[0038] The fuse is a member that protects the circuit board 35 and the plurality of power storage elements 21 from a large current exceeding the rated value. The fuse melts when a current exceeding the rated value flows, thereby interrupting the flow of the current.

[0039] The circuit board 35 has a plurality of electrical components (not shown), and these plurality of electrical components form a detection circuit for detecting the state (temperature, voltage, current, etc.) of each storage element 21, a control circuit for controlling charging and discharging, etc. The circuit board 35 only needs to have at least one of the detection circuit and the control circuit.

[0040] The outer body main body 11 and the outer body cover 12 of the outer body 10 are formed by insulating members such as polycarbonate (PC), polypropylene (PP), polyethylene (PE), polystyrene (PS), polyphenylene sulfide resin (PPS), polyphenylene ether (PPE (including modified PPE)), polyethylene terephthalate (PET), polybutylene terephthalate (PBT), polyetheretherketone (PEEK), tetrafluoroethylene-perfluoroalkyl vinyl ether (PFA), polytetrafluoroethylene (PTFE), polyethersulfone (PES), polyamide (PA), ABS resin, or composite materials thereof, or metals with insulation coating. The outer body 10 thus prevents the storage element 21 and the like from contacting with external metal members and the like. In addition, as long as the structure can maintain the electrical insulation of the storage element 21 and the like, the outer body 10 can also be formed by a conductive member such as a metal. The outer body main body 11 and the outer body cover 12 can be formed by the same material or by different materials.

[0041] [Power storage unit]

[0042] The power storage unit 20 includes a plurality of power storage elements 21 and a holding unit 22 that holds the plurality of power storage elements 21 .

[0043] The storage element 21 is a secondary battery (single cell) that can charge and discharge electricity, more specifically, a non-aqueous electrolyte secondary battery such as a lithium ion secondary battery. In the present embodiment, the storage element 21 is a bag-type storage element having a flat shape, and a plurality of (four in the present embodiment) bag-type storage elements 21 are arranged side by side along the X-axis direction. The storage element 21 may also be a storage element in a flat rectangular parallelepiped shape (square), cylindrical shape, long cylindrical shape or elliptical cylindrical shape instead of a bag-type storage element, and its size and shape are not limited. The number of arranged storage elements 21 is also not particularly limited. The storage element 21 is not limited to a non-aqueous electrolyte secondary battery, but may be a secondary battery other than a non-aqueous electrolyte secondary battery, or may be a capacitor. The storage element 21 may also be a primary battery that the user can use the stored electricity even if it is not charged, instead of a secondary battery. A plurality of storage elements 21 are arranged along the X-axis direction, and adjacent storage elements 21 may be joined to each other by an adhesive or a double-sided tape, or may not be joined. The details of the power storage element 21 will be described later.

[0044] The holding portion 22 is a portion for holding a plurality of storage elements 21. The holding portion 22 includes a holding member 23 and a holding member 24 for holding a plurality of storage elements 21 together with the holding member 23. The holding member 23 is an example of a second holding member, and the holding member 24 is an example of a first holding member. Specifically, the holding member 23 is arranged in the negative direction of the X-axis of the plurality of storage elements 21, and is joined to the storage element 21 at the end portion arranged in the negative direction of the X-axis among the plurality of storage elements 21 by an adhesive or a double-sided tape. The holding member 24 is arranged in the positive direction of the X-axis of the plurality of storage elements 21, and is joined to the storage element 21 at the end portion arranged in the positive direction of the X-axis among the plurality of storage elements 21 by an adhesive or a double-sided tape. Thus, the holding member 23 and the holding member 24 sandwich the plurality of storage elements 21 in the X-axis direction and hold the storage elements. By arranging the holding member 23 opposite to the central part of the storage element 21 arranged at the end in the negative direction of the X-axis, the plurality of storage elements 21 can be held more stably. The same is true for the holding member 24. Here, the central part of the storage element 21 in the Z-axis direction refers to, for example, the central 3-part area when the storage element 21 is divided into 5 equal parts in the Z-axis direction, the central 2-part area when the storage element 21 is divided into 4 equal parts, and the central 1-part area when the storage element 21 is divided into 3 equal parts. The same is true for the Y-axis direction.

[0045] At least one of the holding member 23 and the holding member 24 may not be joined to the energy storage element 21. In this case, the holding member 23 and the holding member 24 can also hold the plurality of energy storage elements 21 by the clamping force received from the outer body main body 11 and the outer body cover 12. In addition, a screw member may be provided between the holding member 23 and the holding member 24 to fasten them, thereby holding the plurality of energy storage elements 21.

[0046] The holding member 23 and the holding member 24 are formed of an insulating member such as polycarbonate (PC), polypropylene (PP), polyethylene (PE), polyphenylene sulfide resin (PPS), polyphenylene ether (PPE (including modified PPE)), polyethylene terephthalate (PET), polybutylene terephthalate (PBT), polyetheretherketone (PEEK), tetrafluoroethylene-perfluoroalkylvinyl ether (PFA), polytetrafluoroethylene (PTFE), polyethersulfone (PES), polyamide (PA), ABS resin, or a composite material thereof. Thus, the holding member 23 and the holding member 24 suppress the situation where the plurality of power storage elements 21 are electrically connected to an external conductive member such as a metal member, but when such a necessity is not met, the holding member 23 and the holding member 24 may be formed of a conductive member such as a metal.

[0047] The holding member 23 includes a flat plate portion 25 overlapping the storage element 21 at the end in the negative direction of the X-axis, and a bus bar support portion 26 extending from the flat plate portion 25 in the positive direction of the X-axis. The bus bar support portion 26 extends from a corner of the flat plate portion 25 in the negative direction of the Y-axis and the negative direction of the Z-axis in the positive direction of the X-axis, and supports a bus bar (not shown).

[0048] The holding member 24 includes a substrate support portion 27 overlapping the storage element 21 at the end portion in the positive direction of the X-axis, and a detection line support portion 28 extending from the substrate support portion 27 in the negative direction of the X-axis. The substrate support portion 27 supports the circuit substrate 35 and includes a surrounding wall 29 surrounding the circuit substrate 35. In addition, the substrate support portion 27 supports a bus bar and a fuse (not shown).

[0049] The detection line support portion 28 supports a plurality of detection lines 36 connected to the circuit board 35 in order to detect the state (temperature, voltage, current, etc.) of each storage element 21. The detection line support portion 28 extends from the negative end of the board support portion 27 in the Y-axis direction in the negative direction of the X-axis.

[0050] [Electrical storage element]

[0051] The details of the power storage element 21 are described below. Figure 2 As shown, the basic structure of the plurality of storage elements 21 is the same, but the outer shapes are partially different. Specifically, the outer shapes of the odd-numbered storage elements 21 and the even-numbered storage elements 21 in the negative direction of the X-axis are partially different. That is, the outer shapes of the odd-numbered storage elements 21 are the same, and the outer shapes of the even-numbered storage elements 21 are the same.

[0052] The basic structure of the storage element 21 is described. The storage element 21 includes an outer film 210 and a pair of (positive and negative) lead terminals 220, and an electrode body (not shown) and an electrolyte (non-aqueous electrolyte: not shown) are contained inside the outer film 210. The type of the electrolyte is not particularly limited as long as it does not impair the performance of the storage element 21, and a known material can be used as appropriate.

[0053] The outer film 210 is a sheet-shaped outer body formed by a laminate film, and an electrode body and an electrolyte are contained in the inner part in a sealed manner in a reduced pressure state. The outer film 210 is formed by overlapping two rectangular laminate films in the X-axis direction. The two laminate films sandwich a pair of lead terminals 220 and are joined (sealed) by heat welding or the like. In the two laminate films, the two laminate films are joined (sealed) to each other by heat welding or the like at a position that does not correspond to the pair of lead terminals 220. The laminate film is a flexible film composed of multiple layers including a metal layer such as aluminum and a resin layer such as polypropylene (PP) or polyethylene (PE), and a resin layer is arranged at the welding position (sealing portion). It is also possible to form a laminate film into a bag shape, and join the ends of the laminate film to each other by heat welding, thereby forming the outer film 210.

[0054] The lead terminal 220 is a conductive plate-shaped member (lead plate) electrically connected to the electrode body, and is configured to be exposed from the outer film 210 in a state where the outer film 210 is penetrated. In the present embodiment, a pair of lead terminals 220 arranged along the Z-axis direction are configured to protrude from the end of the outer film 210 in the negative direction of the Y-axis to the negative direction of the Y-axis. Specifically, the positive lead terminal 220 is a lead terminal electrically connected to the positive electrode plate of the electrode body, and the negative lead terminal 220 is a lead terminal electrically connected to the negative electrode plate of the electrode body. The lead terminal 220 is a metal electrode terminal used to introduce electricity into the internal space of the storage element 21 in order to conduct electricity stored in the electrode body to the external space of the storage element 21 and store electricity in the electrode body. The lead terminal 220 is formed of aluminum, aluminum alloy, copper, copper alloy, etc.

[0055] The electrode body is a storage element (power generation element) formed by stacking a positive plate, a negative plate and a separator. The positive plate has a positive active material layer formed on a collector foil made of a metal such as aluminum or an aluminum alloy. The negative plate has a negative active material layer formed on a collector foil made of a metal such as copper or a copper alloy. As the active material used in the positive active material layer and the negative active material layer, known materials can be used appropriately as long as they can absorb and release lithium ions. The separator can use a microporous sheet or non-woven fabric made of resin. In this embodiment, the electrode plates (positive plates and negative plates) are stacked along the X axis to form an electrode body. In addition, the electrode body can also be a winding type electrode body formed by winding the electrode plates (positive plates and negative plates), a stacked type (stacked type) electrode body formed by stacking a plurality of flat plate-shaped electrode plates, and an electrode body of an accordion type in which the electrode plates are folded into an accordion shape.

[0056] [Joint structure between outer casing and power storage unit]

[0057] The joining structure between the exterior body 10 and the power storage cell 20 will be described. Figure 3: is a cross-sectional perspective view showing the joining structure between the outer casing and the power storage unit according to the embodiment. Specifically, Figure 3 Yes, including Figure 1 A sectional stereogram observed along the cutting plane along line III-III.

[0058] like Figure 3 As shown, the retaining member 23 of the power storage unit 20 is joined to the outer body main body 11 of the outer body 10. Specifically, the outer body main body 11 is formed with a bottom frame 113 protruding in the positive direction of the X-axis on the inner bottom surface 112 opposite to the opening 111 along the X-axis direction. The bottom frame 113 is continuously or intermittently provided along the entire circumference of the inner bottom surface 112. The bottom frame 113 is arranged at a given interval from the inner side surface 11a of the outer body main body 11.

[0059] The rim 251 is provided on the periphery of the flat plate portion 25 of the holding member 23, which is continuously or intermittently along the entire circumference. The rim 251 protrudes from both sides of the flat plate portion 25 in the X-axis direction. A first groove 252 is formed on the end surface of the edge 251 in the negative direction of the X-axis, which is continuously or intermittently along the entire circumference. The bottom frame 113 is inserted into the first groove 252 via an adhesive 253. The first groove 252 and the bottom frame 113 are bonded together as a whole or in part by the adhesive 253, thereby being joined.

[0060] The holding member 24 of the storage cell 20 is joined to the outer cover 12 of the outer body 10. Specifically, the outer cover 12 has a cover frame 123 protruding in the negative direction of the X-axis formed on the inner top surface 121 opposite to the opening 111 along the positive direction of the X-axis. The cover frame 123 is continuous in an annular shape inside the inner top surface 121. The cover frame 123 is arranged with a given interval from the inner side surface 12a of the outer cover 12. The second groove 124 is formed by the cover frame 123 and the inner side surface 12a of the outer cover 12. In the second groove 124, the front end (the end in the positive direction of the X-axis) of the surrounding wall 29 of the holding member 24 is inserted via the adhesive 243. The surrounding wall 29 of the holding member 24 is bonded to the second groove 124 of the outer cover 12 by the adhesive 243 over the entire circumference, thereby being joined.

[0061] In this way, since the holding member 23 is joined to the outer body main body 11 and the holding member 24 is joined to the outer body cover 12, the storage cell 20 is fixed on both sides in the outer body 10. In this state, a gap S1 is formed between the substrate support portion 27 and the outer body cover 12. When viewed in the X-axis direction, the gap S1 is arranged at a position corresponding to the plurality of storage elements 21. That is, the gap S1 is formed between the portion of the substrate support portion 27 that faces the storage element 21 and the outer body cover 12. Even if the plurality of storage elements 21 expands, the expansion is absorbed by the gap S1, so that the expansion is not easily transmitted to the outer body cover 12. In the gap S1, the circuit substrate 35 is arranged on the inner side of the surrounding wall 29. As described above, the front end of the surrounding wall 29 is bonded to the second groove 124 of the outer body cover 12 by the adhesive 243 over the entire circumference, so that the internal space of the surrounding wall 29 is sealed.

[0062] During manufacturing, when assembling the storage cell 20 to the outer body 10, first, the operator applies the adhesive 253 to the bottom frame 113 of the outer body main body 11 or the first groove 252 of the holding member 23. After that, the operator arranges the storage cell 20 in the positive direction of the X axis of the outer body main body 11, and accommodates the storage cell 20 in the outer body main body 11 from the opening 111 by moving the storage cell 20 in the negative direction of the X axis. During this accommodation, the bottom frame 113 is inserted into the first groove 252. Thus, the first groove 252 and the bottom frame 113 are bonded by the adhesive 253.

[0063] Next, the operator applies adhesive 243 to the second groove 124 of the outer cover 12 or the surrounding wall 29 of the retaining member 24. After that, the operator arranges the outer cover 12 in the positive direction of the X axis of the outer body main body 11, and moves the outer cover 12 in the negative direction of the X axis, thereby assembling and bonding the outer cover 12 to the outer body main body 11. At this time, the surrounding wall 29 of the retaining member 24 is inserted into the second groove 124. Thus, the second groove 124 and the surrounding wall 29 are bonded by the adhesive 243. That is, the bonding of the outer body main body 11 and the outer cover 12 and the bonding of the second groove 124 and the surrounding wall 29 are performed through the same process. In particular, the outer film 210 of the storage element 21 is formed of a flexible laminated film, so that the storage element 21 and the retaining members 23, 24 can be more densely bonded to each other. That is, the retaining members 23, 24 can firmly hold the storage element 21. Furthermore, if the plurality of power storage elements 21 are arranged side by side in the X-axis direction, the adjacent power storage elements 21 can be more closely connected to each other. That is, the holding members 23 and 24 can firmly hold the plurality of power storage elements 21 .

[0064] The storage battery unit 20 may be assembled to the exterior body 10 by a process opposite to the above process. That is, after the surrounding wall 29 of the retaining member 24 is bonded to the second groove portion 124 of the exterior body cover 12, the storage battery unit 20 may be inserted into the exterior body main body 11, and the bottom frame 113 of the exterior body main body 11 and the first groove 232 of the retaining member 23 may be bonded.

[0065] [Effects, etc.]

[0066] As described above, according to the present embodiment, the holding member 24 provided at the end of the power storage cell 20 is joined to the exterior body 10, so that the power storage cell 20 is fixed at least on one side in the exterior body 10. Thus, the power storage cell 20 becomes stable in the exterior body 10. Therefore, the vibration resistance or impact resistance of the power storage device 1 can be improved.

[0067] The outer casing body 11, which has one end opened in a given direction (X-axis direction), accommodates the storage cell 20, so that the holding member 23 provided at the other end of the storage cell 20 can be joined to the outer casing body 11 simply by accommodating the storage cell 20 in the outer casing body 11. Furthermore, when the outer casing cover 12 is attached to one end of the outer casing body 11, the holding member 24 provided at one end of the storage cell 20 can be joined to the outer casing cover 12. In this way, the holding member 23 and the holding member 24 provided at the end of the storage cell 20 can be smoothly joined to the outer casing 10.

[0068] The plurality of power storage elements 21 are held by being sandwiched between the holding members 23 and the holding members 24, and thus the plurality of power storage elements 21 are further stabilized in the exterior body 10 by the holding members 23 and the holding members 24. Furthermore, since the holding members 24 are joined to the exterior body cover 12 and the holding members 23 are joined to the exterior body main body 11, the power storage unit 20 is fixed on both sides in the exterior body 10. Thus, the vibration resistance or impact resistance of the power storage device 1 can be further improved.

[0069] A gap S1 is formed between the holding member 24 and the exterior cover 12 at positions corresponding to the plurality of energy storage elements 21, so that expansion of the plurality of energy storage elements 21 can be absorbed by the gap S1. Therefore, deformation of the exterior 10 caused by expansion of the plurality of energy storage elements 21 can be suppressed.

[0070] Since the circuit substrate 35 is disposed in the gap S1, the circuit substrate 35 can be accommodated even without providing a dedicated member covering the circuit substrate 35. If a dedicated member is not required, the weight can be reduced, thereby further improving the vibration resistance or impact resistance. Furthermore, if a dedicated member is not required, space saving in the outer casing 10 can be achieved, and the power storage device 1 can be miniaturized.

[0071] (Variant 1)

[0072] Hereinafter, a modification 1 of the above embodiment will be described. In the following description, the same reference numerals may be used to denote the same parts as those of the above embodiment or other modifications, and the description thereof may be omitted.

[0073] In the above-described embodiment, the electric storage cell 20 including the pair of holding members 23 and 24 is exemplified. In this modification 1, an electric storage cell including only one holding member is described. Figure 4 : is a cross-sectional perspective view showing the joining structure between the outer casing and the power storage unit according to Modification 1. Specifically, Figure 4 is with Figure 3 The corresponding figure.

[0074] like Figure 4 As shown, the storage unit 20A has a holding member 24 as a first holding member, but does not have a holding member 23 as a second holding member. Therefore, in the storage unit 20A, the end in the negative direction of the X axis becomes the first storage element 21 in the negative direction of the X axis. The adhesive 253a is interposed between the first storage element 21 and the inner bottom surface 112 of the outer body main body 11, and the storage element 21 and the inner bottom surface 112 are bonded and joined. That is, in this case, the storage unit 20A is also fixed on both sides in the outer body 10.

[0075] (other)

[0076] The above describes the power storage device according to the embodiment of the present invention, but the present invention is not limited to the above embodiment. That is, the embodiment disclosed this time is illustrative in all aspects and is not restrictive, and the scope of the present invention includes the meaning equivalent to the scope of the patent claims and all changes within the scope.

[0077] In the above embodiment, the holding member 24 is set as an example of the first holding member, and the holding member 23 is set as an example of the second holding member. However, the relationship between the first holding member and the second holding member may be reversed. Specifically, the holding member 23 may be set as an example of the first holding member, and the holding member 24 may be set as an example of the second holding member. For example, when the holding member 23 is set as an example of the first holding member, the holding member 24 can be removed as in Modification 1, and the fourth energy storage element 21 can be joined (bonded) to the outer cover 12.

[0078] Furthermore, if the first retaining member is joined to the outer casing, the second retaining member may not be joined to the outer casing. In this case, the storage unit is also fixed on one side in the outer casing, so the storage unit is stable in the outer casing. Therefore, the vibration resistance or impact resistance of the storage device can be improved.

[0079] In the above embodiment, bonding is exemplified as a method of bonding objects to be bonded. However, bonding objects to be bonded may be bonded by methods other than bonding. Other methods include welding, fixing with bolts and nuts, and the like.

[0080] In the above embodiment, the case where the gap S1 is formed between the substrate support portion 27 of the retaining member 24 and the outer body cover 12 is exemplified. However, a gap may be provided between the retaining member 23 and the inner bottom surface 112 of the outer body main body 11. Even with this gap, the expansion of the storage element 21 can be absorbed, and the deformation of the outer body caused by the expansion can be suppressed. The gap only needs to be provided in at least one of the gap between the retaining member 24 and the outer body cover 12 and the gap between the retaining member 23 and the outer body main body 11. In addition, no gap may be provided.

[0081] In the above embodiment, the circuit substrate 35 is arranged in the gap S1 between the substrate support portion 27 of the holding member 24 and the exterior body cover 12. In the case where a gap is provided between the holding member 23 and the inner bottom surface 112 of the exterior body main body 11, the circuit substrate 35 may be arranged in the gap. In addition, the circuit substrate may not be arranged in the gap.

[0082] In the above embodiment, the outer casing body 11 having the opening 111 at the end in the X-axis direction (given direction) is exemplified, but the opening may be at any position. For example, the outer casing body may have an opening at the end in a direction intersecting the X-axis direction.

[0083] A configuration in which the components included in the embodiment and its modified examples are arbitrarily combined is also included in the scope of the present invention.

[0084] Industrial Applicability

[0085] The present invention can be applied to a power storage device including a power storage element such as a lithium ion secondary battery, and the like.

[0086] Explanation of symbols

[0087] 1 Power storage device

[0088] 10 outer body

[0089] 11 Main body of outer body

[0090] 11a, 12a inner side

[0091] 12 Exterior body cover

[0092] 20, 20A storage unit

[0093] 21 Storage element

[0094] 22. Holding unit

[0095] 23 Holding member (second holding member)

[0096] 24 Holding member (first holding member)

[0097] 25 Flat Plate

[0098] 26 Bus bar support

[0099] 27 substrate support

[0100] 28 Testing line support

[0101] 29 walls

[0102] 35 Circuit board

[0103] 36 Testing Line

[0104] 81 External terminal

[0105] 111 Opening

[0106] 112 inner bottom

[0107] 113 bottom frame

[0108] 121 inner top surface

[0109] 123 Cover frame

[0110] 124 Second groove

[0111] 210 exterior film

[0112] 220 Lead Terminal

[0113] 243, 253, 253a Adhesive

[0114] 251 Edge

[0115] 252 First Groove

[0116] S1 gap.

Claims

1. A power storage device comprising: a power storage unit; and an outer casing accommodating the power storage unit, The power storage unit comprises: A plurality of power storage elements arranged in a given direction; and a first holding member adjacent to the plurality of power storage elements in the given direction and holding the plurality of power storage elements, The first holding member is joined to the exterior body.

2. The power storage device according to claim 1, wherein The outer casing has: an outer casing body having an opening at one end in the given direction; and The outer casing cover is mounted on the one end portion of the outer casing main body and closes the opening.

3. The power storage device according to claim 1 or 2, wherein: The power storage unit further includes a second holding member for holding the plurality of power storage elements. The second holding member is disposed at a position where the plurality of power storage elements are sandwiched together with the first holding member in the given direction, and is joined to the exterior body.

4. The power storage device according to claim 3, wherein: A gap is formed between at least one of the first holding member and the second holding member and the exterior body at a position corresponding to the plurality of power storage elements.

5. The power storage device according to claim 4, wherein: A circuit board is arranged in the gap.

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