Power storage device

Abstract

To provide a power storage device including an outer package which achieves improvement of reliability with a simple structure.SOLUTION: A power storage device 1 includes: a power storage unit 101 including a power storage element 100; an outer package 10 which houses the power storage unit; and a conductive member 200 electrically connected to the power storage unit. The outer package includes a wall part 21 spaced apart from the power storage unit and facing the power storage unit. The conductive member includes a bus bar 210. The bus bar includes: a first fixing part 211 fixed to the power storage unit; a second fixing part 215 fixed to the wall part; and a contact part 218 which contacts with an inner surface of the wall part at a position different from that of the second fixing part.SELECTED DRAWING: Figure 3

Description

[Technical Field]

[0001] The present invention relates to an electricity storage device. [Background technology]

[0002] Patent Document 1 discloses an energy storage module. This energy storage module includes an energy storage device having terminal portions on its end surfaces, a hold case that holds the energy storage device, a bus bar connected to the terminal portions, and a fixing portion that is provided on the hold case and to which the bus bar is fixed. The bus bar includes a first terminal connection portion that is connected to the terminal portions, a main body portion that is fixed to the fixing portion, and a second terminal connection portion. The second terminal connection portion is located on the opposite side of the main body portion from the first terminal connection portion. The first terminal connection portion is welded to the terminal portion of the energy storage device, and the second terminal connection portion is welded to an external output terminal provided on the hold case. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] International Publication No. 2020 / 203734 Summary of the Invention [Problem to be solved by the invention]

[0004] In the conventional energy storage module described above, the bus bar body is fixed to the fixing portion by being press-fitted into a hole in the fixing portion of the hold case. In other words, in order to restrict the movement of the bus bar body, it is necessary to press-fit the bus bar body into the hole. This can complicate the configuration and / or manufacturing process of the energy storage module.

[0005] The present invention was made by the present inventors by focusing on the above-mentioned problem, and has an object to provide an electricity storage device including an exterior body with a simple configuration and improved reliability. [Means for solving the problem]

[0006] An energy storage device according to one aspect of the present invention includes an energy storage unit having an energy storage element, an exterior body that houses the energy storage unit, and a conductive member electrically connected to the energy storage unit, wherein the exterior body includes a wall portion that is spaced apart from the energy storage unit and faces the energy storage unit, and the conductive member includes a bus bar that includes a first fixing portion fixed to the energy storage unit, a second fixing portion fixed to the wall portion, and a contact portion that contacts an inner surface of the wall portion at a position different from the second fixing portion. [Effects of the Invention]

[0007] According to the present invention, it is possible to provide an electricity storage device that includes an exterior body with a simple configuration and improved reliability. [Brief explanation of the drawings]

[0008] [Figure 1] FIG. 1 is a perspective view showing the appearance of a power storage device according to an embodiment. [Figure 2] FIG. 2 is an exploded perspective view of the electricity storage device according to the embodiment. [Figure 3] FIG. 3 is a diagram showing the configuration of the conductive member and its surroundings according to the embodiment. [Figure 4] FIG. 4 is a diagram showing a configuration of a conductive member and its surroundings according to the first modification of the embodiment. [Figure 5] FIG. 5 is a diagram showing a configuration of a conductive member and its surroundings according to the second modification of the embodiment. [Figure 6] FIG. 6 is a diagram showing a configuration of a conductive member and its surroundings according to a third modification of the embodiment. [Figure 7] FIG. 7 is a diagram showing a configuration of a conductive member and its surroundings according to a fourth modification of the embodiment. [Figure 8] FIG. 8 is a diagram showing a configuration of a conductive member and its surroundings according to a fifth modification of the embodiment. DETAILED DESCRIPTION OF THE INVENTION

[0009] (1) An energy storage device according to one aspect of the present invention includes an energy storage unit including an energy storage element, an exterior housing that houses the energy storage unit, and a conductive member electrically connected to the energy storage unit, wherein the exterior housing includes a wall portion that is spaced apart from the energy storage unit and faces the energy storage unit, and the conductive member includes a bus bar that includes a first fixing portion fixed to the energy storage unit, a second fixing portion fixed to the wall portion, and a contact portion that contacts an inner surface of the wall portion at a position different from the second fixing portion.

[0010] In an energy storage device according to one aspect of the present invention, the conductive member is fixed to the wall of the energy storage unit and the exterior body, and has a contact portion that contacts the inner surface of the wall at a position different from the fixed position (second fixing portion) to the wall. Therefore, deformation of the portion of the conductive member between the first fixing portion and the second fixing portion is suppressed. This suppresses deterioration or damage to the conductive member due to vibration, impact, or the like. Thus, the energy storage device according to this aspect is a simple configuration with improved reliability.

[0011] (2) In the energy storage device described in (1) above, the conductive member may further include an electrical device connected to the bus bar and disposed between the first fixed portion and the second fixed portion.

[0012] According to the power storage device described in (2) above, when the power storage device is subjected to, for example, vibration or impact, movement of the electrical device may deform the conductive member, but since the contact portion is in contact with the wall portion, such deformation is suppressed, thereby further improving reliability with a simple configuration.

[0013] (3) In the power storage device described in (2) above, the contact portion may be disposed between the first fixing portion and the electric device.

[0014] According to the power storage device described in (3) above, even if the electrical device vibrates due to external vibration or impact, the vibration of the electrical device is easily absorbed by the wall portion via the contact portion. This suppresses propagation of the vibration to the power storage unit. As a result, deterioration or damage to the power storage unit due to the vibration is further suppressed.

[0015] (4) In the energy storage device described in (2) or (3) above, the busbar may include a first busbar and a second busbar, the first busbar may include the first fixing portion at one end of the first busbar, and the electrical device may be connected to the other end of the first busbar, and the second busbar may include the second fixing portion at one end of the second busbar, and the electrical device may be connected to the other end of the second busbar.

[0016] According to the energy storage device described in (4) above, even if the length of the conductive member is increased by disposing an electric device between the first bus bar and the second bus bar, the contact portion comes into contact with the wall portion, so deformation of the bus bar is suppressed, thereby further improving reliability with a simple configuration.

[0017] (5) In the energy storage device according to any one of (1) to (4) above, the contact portion may be a part of the bus bar that is bent so as to protrude toward the wall portion.

[0018] According to the energy storage device described in (5) above, since the contact portion is part of the bus bar, the contact portion can be easily formed so as to appropriately contact the wall portion, thereby further improving reliability with a simple configuration.

[0019] Hereinafter, with reference to the drawings, a description will be given of an energy storage device (including its modified examples) according to an embodiment of the present invention. The embodiments described below are all comprehensive or specific examples. The numerical values, shapes, materials, components, component placement and connection configurations, manufacturing processes, and the order of manufacturing processes shown in the following embodiments are examples and are not intended to limit the present invention. Furthermore, in each drawing, dimensions and the like are not strictly illustrated. Furthermore, in each drawing, the same or similar components are assigned the same reference numerals.

[0020] In the following description and drawings, the X-axis direction is defined as the direction in which a pair of terminals in one energy storage element are aligned, or the direction in which a pair of short side surfaces in one energy storage element face each other. The Y-axis direction is defined as the direction in which multiple energy storage elements are aligned, the direction in which a pair of long side surfaces in one energy storage element face each other, or the thickness direction of the energy storage element. The Z-axis direction is defined as the direction in which the container body and the cover plate in the container of the energy storage element are aligned, the direction in which the exterior body and the cover in the exterior body are aligned, or the up-down direction. The X-axis direction, Y-axis direction, and Z-axis direction intersect each other (orthogonal in this embodiment). Note that, depending on the mode of use, the Z-axis direction may not be the up-down direction; however, for convenience of explanation, the following description will be made assuming that the Z-axis direction is the up-down direction.

[0021] In the following description, for example, the positive X-axis direction refers to the direction of the arrow on the X-axis, and the negative X-axis direction refers to the direction opposite to the positive X-axis direction. When simply referring to the X-axis direction, it refers to both or either of the positive X-axis direction and the negative X-axis direction. The same applies to the Y-axis and Z-axis directions. Expressions indicating relative directions or attitudes, such as parallel and perpendicular, also include cases where the directions or attitudes are not strictly the same. For example, when two directions are parallel, it does not only mean that the two directions are completely parallel, but also means that the directions are substantially parallel, that is, there is a difference of, for example, a few percent. Furthermore, in the following description, when the term "insulation" is used, it means "electrical insulation." An insulating material has a volume resistivity of 1×10 6 Ωm or more, more preferably 1×10 7Ωm or more, more preferably 1×10 10 It is preferable that the material be made of a material with a resistance of Ωm or more.

[0022] (Embodiment) [1. General description of the power storage device] First, an outline of the configuration of an energy storage device 1 according to the present embodiment will be described. Fig. 1 is a perspective view showing the appearance of the energy storage device 1 according to the embodiment. Fig. 2 is an exploded perspective view of the energy storage device 1 according to the embodiment. In addition to the components shown in Fig. 2, the exterior body 10 may house a plurality of bus bars connecting the plurality of energy storage elements 100, and may further contain spacers arranged along the energy storage elements 100, restraining members restraining the plurality of energy storage elements 100, and the like. However, illustration and description of these components will be omitted.

[0023] The power storage device 1 is a device that can charge with electricity from an external source and discharge electricity to an external source. The power storage device 1 is, for example, a battery module (battery assembly) used for power storage or power supply purposes. Specifically, the power storage device 1 is used as a battery for driving or starting the engine of a moving object such as an automobile, motorcycle, personal watercraft, ship, snowmobile, agricultural machinery, construction machinery, automatic guided vehicle (AGV), or electric railway vehicle. Examples of the automobile include an electric vehicle (EV), a hybrid electric vehicle (HEV), a plug-in hybrid electric vehicle (PHEV), and a fossil fuel (gasoline, diesel, liquefied natural gas, etc.) vehicle. Examples of the electric railway vehicle include a train, a monorail, a linear motor car, and a hybrid train equipped with both a diesel engine and an electric motor. The power storage device 1 can also be used as a stationary battery for home or business use.

[0024] 1 and 2, the energy storage device 1 includes an exterior body 10, an energy storage unit 101 having an energy storage element 100, and a conductive member 200 connected to the energy storage unit 101. The energy storage unit 101 and the conductive member 200 are housed in the exterior body 10. The exterior body 10 is a box-shaped (approximately rectangular parallelepiped) container (module case) that constitutes the housing of the energy storage device 1. The rectangular parallelepiped here refers to a hexahedron with all faces formed into rectangles or squares.

[0025] That is, the exterior housing 10 is disposed outside the energy storage unit 101 to protect the energy storage unit 101. The exterior housing 10 is formed of an insulating material such as polycarbonate (PC), polypropylene (PP), polyethylene (PE), polystyrene (PS), polyphenylene sulfide resin (PPS), polyphenylene ether (PPE (including modified PPE)), polyethylene terephthalate (PET), polybutylene terephthalate (PBT), polyether ether ketone (PEEK), tetrafluoroethylene-perfluoroalkyl vinyl ether (PFA), polytetrafluoroethylene (PTFE), polyethersulfone (PES), polyamide (PA), ABS resin, or a composite material thereof. The exterior housing 10 thereby prevents the energy storage element 100 and the like from coming into contact with external metal members and the like.

[0026] The exterior body 10 includes an exterior body main body 12 and a lid body 20. The exterior body main body 12 is a rectangular cylindrical housing with a bottom and an opening 13a. The opening 13a is provided at the end of the exterior body main body 12 in the positive direction of the Z axis. The lid body 20 is a member that closes the opening 13a of the exterior body main body 12. The lid body 20 is spaced apart from the power storage unit 101 and includes a wall portion 21 that faces the power storage unit 101. A pair of external terminals 90, one for a positive electrode and one for a negative electrode, are arranged on the wall portion 21.

[0027] The energy storage device 1 is charged with electricity from the outside and discharges electricity to the outside via the pair of external terminals 90. The external terminals 90 are formed of a conductive member made of metal such as aluminum, an aluminum alloy, copper, or a copper alloy. When distinguishing between the pair of external terminals 90, the positive external terminal 90 is referred to as external terminal 90A, and the negative external terminal 90 is referred to as external terminal 90B.

[0028] After the power storage unit 101 and the like are housed in the exterior body main body 12, the lid body 20 is fixed to the exterior body main body 12. Specifically, the lid body 20 is joined to the exterior body main body 12 by adhesive, heat sealing (thermal welding), ultrasonic welding, laser welding, screw connection, or the like.

[0029] The energy storage unit 101 includes energy storage elements 100. The energy storage unit 101 according to this embodiment includes five energy storage elements 100. The five energy storage elements 100 are aligned in the Y-axis direction with their long side surfaces 110a facing the Y-axis direction. The energy storage unit 101 may include spacers or holders (not shown) arranged along the energy storage elements 100. The energy storage unit 101 may also include restraining members (not shown) that restrain the plurality of energy storage elements 100 in the alignment direction.

[0030] There are no particular limitations on the number of energy storage elements 100 included in the energy storage unit 101 and the manner in which the multiple energy storage elements 100 are electrically connected. In this embodiment, the five energy storage elements 100 included in the energy storage unit 101 are connected in series by multiple bus bars (not shown). Each of the multiple bus bars is held by a bus bar plate 50. The bus bar plate 50 is an insulating member made of a resin such as PC, PP, PE, or PS. The bus bar plate 50 has multiple bus bar openings 51, and a bus bar is arranged in each of the multiple bus bar openings 51.

[0031] The energy storage element 100 is a secondary battery, more specifically, a nonaqueous electrolyte secondary battery such as a lithium-ion secondary battery. As shown in FIG. 2 , the energy storage element 100 includes a flat rectangular (square) container 110. The container 110 contains an electrode assembly, a current collector, an electrolyte, and other components (not shown). The electrode assembly may be, for example, a wound type formed by winding an electrode plate and a separator, a stacked type formed by stacking multiple flat electrode plates, or a bellows-type electrode assembly formed by folding an electrode plate into an accordion shape. The type of electrolyte contained in the container 110 is not particularly limited as long as it does not impair the performance of the energy storage element 100, and various types can be selected. The energy storage element 100 may be a secondary battery other than a nonaqueous electrolyte secondary battery, or a capacitor. The energy storage element 100 may be a primary battery. The energy storage element 100 may be a pouch-type energy storage element. The energy storage element 100 may be a battery using a solid electrolyte. The shape of the energy storage element 100 is not limited to the above-mentioned rectangular shape, and may be other shapes such as a polygonal column, a cylindrical column, an elliptical column, or an oblong column.

[0032] 2, the container 110 is a rectangular parallelepiped case having a pair of long sides 110a, a pair of short sides 110b, a bottom surface 110d, and a terminal arrangement surface 110c. A pair of terminals 120 and a gas exhaust valve 105 are provided on the terminal arrangement surface 110c. After an electrode assembly and the like are housed inside the main body (container body) of the container 110, the container body and a cover plate that forms the terminal arrangement surface 110c are welded together to seal the interior. The material of the container 110 is not particularly limited, but is preferably a weldable metal such as stainless steel, aluminum, an aluminum alloy, iron, or plated steel sheet.

[0033] The terminals 120 are electrically connected to the electrode assembly housed in the container 110 and are provided so as to protrude from the terminal arrangement surface 110c. One of the pair of terminals 120 is electrically connected to the positive electrode of the electrode assembly, and the other is electrically connected to the negative electrode of the electrode assembly. The terminals 120 are formed of a conductive material such as aluminum, an aluminum alloy, copper, or a copper alloy.

[0034] In this embodiment, as described above, five energy storage elements 100 are connected in series. Of the five energy storage elements 100, the positive electrode terminal 120 of the energy storage element 100 at the end in the positive direction of the Y axis functions as the positive terminal 120A of the energy storage unit 101 (see FIG. 2). Of the five energy storage elements 100, the negative electrode terminal 120 of the energy storage element 100 at the end in the negative direction of the Y axis functions as the negative terminal 120B of the energy storage unit 101 (see FIG. 2). The positive terminal 120A is electrically connected to the positive external terminal 90A via the conductive member 200. The negative terminal 120B is electrically connected to the negative external terminal 90B via a bus bar or the like (not shown). In other words, the energy storage unit 101 is charged with electricity from the outside and discharges electricity to the outside via the external terminals 90A and 90B.

[0035] Conductive member 200 is a member electrically connected to power storage unit 101. In the present embodiment, conductive member 200 includes bus bar 210. Bus bar 210 includes contact portion 218 that comes into contact with wall portion 21 of exterior body 10. This suppresses deformation of conductive member 200, and as a result, suppresses deterioration or damage to conductive member 200. Hereinafter, the configuration of conductive member 200 and its surroundings according to the present embodiment will be described with reference to FIG. 3 in addition to the above-mentioned FIG. 2.

[0036] 2. Configuration of the Conductive Member 200 and Its Surrounding Area FIG. 3 is a diagram showing a configuration of a conductive member 200 and its surroundings according to an embodiment. In FIG. 3, a cross section parallel to the YZ plane passing through line III-III in FIG. 2 is simply illustrated for the exterior housing 10, the bus bar plate 50, and the external terminal 90A. In FIG. 3, a side view of the power storage unit 101 and the conductive member 200 as viewed from the positive direction of the X axis is simply illustrated. Furthermore, in FIG. 3, a pattern is applied to the electric device 280 to distinguish it from other components. These supplementary notes regarding FIG. 3 also apply, as appropriate, to FIGS. 4 to 8, which will be described later.

[0037] As shown in FIG. 3, in the energy storage device 1 according to this embodiment, the energy storage unit 101 housed in the exterior body 10 is electrically connected to an external terminal 90A arranged on the wall portion 21 of the exterior body 10 via a conductive member 200.

[0038] Specifically, conductive member 200 according to the present embodiment includes bus bar 210. Bus bar 210 includes first fixing portion 211 and second fixing portion 215. First fixing portion 211 is a portion fixed to power storage unit 101. In the present embodiment, first fixing portion 211 is joined to general positive terminal 120A of power storage unit 101 by welding, crimping, or a bolt, nut, or the like (not shown). Second fixing portion 215 is a portion fixed to wall portion 21 of exterior body 10 (more specifically, wall portion 21 of lid 20). In the present embodiment, second fixing portion 215 is joined to external terminal 90A disposed to penetrate wall portion 21 by welding, crimping, a bolt, nut, or the like (not shown). That is, second fixing portion 215 is fixed to wall portion 21 of exterior body 10 via external terminal 90A. 3, second fixing portion 215 is located inside wall portion 21 (negative direction of the Z axis), but this is not essential. At least a portion of second fixing portion 215 may be joined to external terminal 90A in a state where it is contained inside wall portion 21. At least a portion of second fixing portion 215 may be joined to external terminal 90A in a state where it is exposed outside wall portion 21 (positive direction of the Z axis).

[0039] As described above, the bus bar 210 of the conductive member 200 is fixed to the power storage unit 101 and the wall portion 21, which are spaced apart in the Z-axis direction and opposed to each other in the Z-axis direction. That is, the conductive member 200 is fixed at at least two locations (the first fixing portion 211 and the second fixing portion 215) that are spaced apart in the Z-axis direction. Therefore, when the power storage device 1 is subjected to vibration or impact, it is conceivable that the portion of the conductive member 200 between the first fixing portion 211 and the second fixing portion 215 will deform. For example, the vibration or impact may cause vibration and / or bending of the portion. As a result, it is conceivable that the portion will be damaged, for example, by metal fatigue. However, the conductive member 200 according to this embodiment has a contact portion 218 on the bus bar 210 that contacts the wall portion 21, and a configuration is adopted in which the contact portion 218 suppresses deformation of the conductive member 200.

[0040] That is, the energy storage device 1 according to the present embodiment includes an energy storage unit 101 including energy storage elements 100, an exterior body 10 that houses the energy storage unit 101, and a conductive member 200 electrically connected to the energy storage unit 101. The exterior body 10 includes a wall portion 21 that is spaced apart from the energy storage unit 101 and faces the energy storage unit 101. The conductive member 200 includes a bus bar 210. The bus bar 210 includes a first fixing portion 211 fixed to the energy storage unit 101, a second fixing portion 215 fixed to the wall portion 21, and a contact portion 218 that comes into contact with the inner surface of the wall portion 21 at a position different from that of the second fixing portion 215.

[0041] As described above, the conductive member 200 included in the energy storage device 1 according to the present embodiment is fixed to the energy storage unit 101 and the wall portion 21 of the exterior body 10, and has the contact portion 218 that contacts the inner surface of the wall portion 21 at a position different from the fixed position (second fixing portion 215) to the wall portion 21. Therefore, the conductive member 200, whose movement is restricted at two positions, the first fixing portion 211 and the second fixing portion 215, can also be restricted by the wall portion 21 at positions other than the second fixing portion 215, by further including the contact portion 218. As a result, deformation of the conductive member 200 is suppressed. This suppresses deterioration or damage to the conductive member 200 due to vibration, impact, or the like. Furthermore, because the contact portion 218 only needs to contact the inner surface of the wall portion 21 of the exterior body 10, a step of press-fitting the contact portion 218 into the wall portion 21 and a configuration therefor (such as a press-fit hole) are not required. Unlike when contact portion 218 is fixed to wall portion 21 by press-fitting into wall portion 21 or by integral molding with wall portion 21, contact portion 218 can easily move in a direction along the inner surface of wall portion 21. This is advantageous in terms of absorbing the size tolerance of components such as bus bar 210 or exterior body 10. In this way, energy storage device 1 according to this embodiment is an energy storage device 1 with a simple configuration and improved reliability.

[0042] In the present embodiment, the contact portion 218 comes into contact with the wall portion 21, thereby restricting movement at least in a direction toward the wall portion 21 (in the present embodiment, the positive direction of the Z axis). Therefore, the contact portion 218 does not need to be fixed to the wall portion 21. However, the contact portion 218 may be fixed to the wall portion 21 while being in contact with the wall portion 21. That is, the contact portion 218 may be bonded to the wall portion 21 with, for example, an adhesive, so that the contact portion 218 comes into contact with and is fixed to the wall portion 21. In this case, movement of the contact portion 218 in various directions, including the positive direction of the Z axis and the negative direction of the Z axis, is restricted. As a result, deformation of the conductive member 200 due to vibration, impact, or the like is more reliably suppressed. However, for example, from the viewpoint of simplifying the configuration of the power storage device 1, it is preferable not to fix the contact portion 218 to the wall portion 21.

[0043] In the present embodiment, second fixing portion 215 is fixed to wall portion 21 of exterior body 10 via external terminal 90A, as described above. Therefore, second fixing portion 215 does not need to contact wall portion 21 (see FIG. 3). However, second fixing portion 215 may be fixed to wall portion 21 while contacting wall portion 21. This more reliably restricts, for example, movement of second fixing portion 215. This contributes to suppressing deformation of conductive member 200 due to vibration, impact, or the like.

[0044] More specifically, conductive member 200 according to the present embodiment includes electric device 280 connected to bus bar 210 and disposed between first fixed portion 211 and second fixed portion 215. Examples of electric device 280 included in conductive member 200 include a relay, a resistor, a fuse, a control circuit, or a sensor for detecting temperature or the like, or a device including two or more of these components (members).

[0045] As described above, the conductive member 200 includes the electric device 280 between the first fixed portion 211 and the second fixed portion 215. Providing the electric device 280 in the conductive member 200 is useful for, for example, miniaturizing the power storage device 1, stably controlling the power storage device 1, and / or improving the safety of the power storage device 1. On the other hand, when the power storage device 1 is subjected to, for example, vibration or impact, movement of the electric device 280 may deform the conductive member 200. However, the conductive member 200 according to this embodiment includes the contact portion 218 that contacts the inner surface of the wall portion 21, thereby suppressing deformation due to vibration or impact. This configuration is particularly useful when the weight of the electric device 280 is relatively large. For example, when the electric device 280 is a relay (also called a mechanical relay, for example) that includes an electromagnet, the weight of the electric device 280 becomes relatively large. Therefore, it can be said that providing the conductive member 200 with the contact portion 218 that comes into contact with the inner surface of the wall portion 21 is highly useful from the viewpoint of suppressing deformation of the conductive member 200.

[0046] Since the electric device 280 is disposed between the first fixed portion 211 and the second fixed portion 215, even if the electric device 280 vibrates due to an external vibration or impact, the vibration of the electric device 280 is easily absorbed by the wall portion 21 via the contact portion 218. This allows the vibration of the electric device 280 to converge quickly, and also suppresses propagation of the vibration to the first fixed portion 211 or the second fixed portion 215. This further contributes to improving the reliability of the power storage device 1.

[0047] 2 and 3, the electric device 280 is shown schematically as a rectangular parallelepiped object, but the shape and size of the electric device 280 do not have to be the shape and size shown in Fig. 2 and 3. The type of the electric device 280 may be selected according to the performance or specifications required of the power storage device 1, and the shape and size of the electric device 280 may be determined according to the selection.

[0048] In this embodiment, the contact portion 218 is disposed between the first fixed portion 211 and the electric device 280, as shown in FIGS.

[0049] According to this configuration, even if the electric device 280 vibrates due to external vibration or impact, the vibration of the electric device 280 is easily absorbed by the wall 21 via the contact portion 218, and therefore, propagation of the vibration to the power storage unit 101 is suppressed. As a result, deterioration or damage to the power storage unit 101 caused by the vibration is further suppressed.

[0050] In this embodiment, bus bar 210 includes at least two bus bars that are separate from each other. Specifically, as shown in Fig. 2 and Fig. 3, bus bar 210 includes first bus bar 220 and second bus bar 230. First bus bar 220 includes first fixing portion 211 at one end thereof, and electric device 280 is connected to the other end thereof. Second bus bar 230 includes second fixing portion 215 at one end thereof, and electric device 280 is connected to the other end thereof.

[0051] As described above, in the present embodiment, electric device 280 is disposed between first bus bar 220 and second bus bar 230, which makes it easy to attach electric device 280 to conductive member 200. Even if the length of conductive member 200 is increased by disposing electric device 280 between first bus bar 220 and second bus bar 230, contact portion 218 comes into contact with wall portion 21, so deformation of bus bar 210 is suppressed.

[0052] 2 and 3, electrical device 280 may be provided with connection terminals at both ends in the Y-axis direction for connecting to first bus bar 220 and second bus bar 230. In this case, first bus bar 220 and second bus bar 230 may be joined to the corresponding connection terminals by a predetermined method such as screw connection, welding, or crimping.

[0053] In the present embodiment, contact portion 218 is a part of bus bar 210 that is bent so as to protrude toward wall portion 21. More specifically, in the present embodiment, contact portion 218 is provided on first bus bar 220 that bus bar 210 includes.

[0054] In this way, contact portion 218 can be formed by bending a portion of metal bus bar 210, for example. Therefore, contact portion 218 can be easily formed so as to appropriately contact wall portion 21. Because the portion forming contact portion 218 is a bent portion of bus bar 210, a tension force is likely to be generated between power storage unit 101 and wall portion 21, for example. In other words, contact portion 218 functions like a spring, and can press wall portion 21 with an appropriate force in the positive direction of the Z axis. This is advantageous in suppressing deformation of conductive member 200.

[0055] The above has described the energy storage device 1 according to the embodiment, focusing on the configuration of the conductive member 200 and its periphery. However, the configuration of the conductive member 200 and its periphery in the energy storage device 1 may be different from the configurations shown in Figures 2 and 3. Therefore, below, modifications of the configuration of the conductive member 200 and its periphery will be described, focusing on the differences from the above embodiment.

[0056] [3-1. Variation 1] 4 is a diagram showing a configuration of a conductive member 200a and its surroundings according to Modification 1 of the embodiment. Energy storage device 1 according to this modification includes conductive member 200a connected to energy storage unit 101. Conductive member 200a includes bus bar 210, and bus bar 210 includes first fixing portion 211, second fixing portion 215, and contact portion 218a.

[0057] As shown in FIG. 4 , the contact portion 218a according to this modification is a part of the bus bar 210 that is bent into a curved shape so as to protrude toward the wall portion 21. In this respect, it differs from the contact portion 218 according to the embodiment. That is, as shown in FIG. 3 , the contact portion 218 according to the embodiment has a trapezoidal shape when viewed from the X-axis direction, whereas the contact portion 218a according to this modification has a curved shape that is convex in the positive Z-axis direction when viewed from the X-axis direction. Even in this case, the contact portion 218a contacts the inner surface of the wall portion 21 at a position different from the second fixing portion 215, thereby suppressing deformation of the conductive member 200a. The curved shape of the contact portion 218a improves the ease of deformation when it comes into contact with the inner surface of the wall portion 21. The curved shape of the contact portion 218a makes it easier for the contact portion 218a to be in appropriate contact with the wall portion 21, even when the conductive member 200a is disposed in an orientation tilted in the Z-axis direction. These are advantageous in terms of absorbing the tolerances in the sizes of components such as the bus bar 210 or the exterior body 10, for example.

[0058] In this modification, curved contact portion 218a is exemplified, but the shape of contact portion 218a when viewed from the X-axis direction is not limited to a trapezoid or a curved shape, and various shapes may be adopted, such as a rectangle, a polygonal shape other than a rectangle, or a shape consisting of a combination of straight lines and curves. This also applies to contact portions (contact portions 218a to 218e) in other modifications described below.

[0059] [3-2. Variation 2] 5 is a diagram showing a configuration of a conductive member 200b and its surroundings according to Modification 2 of the embodiment. Energy storage device 1 according to this modification includes conductive member 200b connected to energy storage unit 101. Conductive member 200b includes bus bar 210, and bus bar 210 includes first fixing portion 211, second fixing portion 215, and contact portion 218b.

[0060] 5, bus bar 210 of conductive member 200b according to this modification includes two contact portions 218b aligned in the Y-axis direction, which differs from contact portion 218 according to the embodiment. That is, bus bar 210 of conductive member 200b according to this modification contacts two locations on the inner surface of wall portion 21 at positions different from second fixing portion 215. Even in this case, two contact portions 218b contact the inner surface of wall portion 21 at positions different from second fixing portion 215, thereby suppressing deformation of conductive member 200b.

[0061] In this way, by providing conductive member 200b with multiple contact portions 218b, bus bar 210 can be brought into balanced contact with multiple locations on the inner surface of wall portion 21, while avoiding, for example, portions on the inner surface of wall portion 21 where contact with bus bar 210 is not desired or where contact with bus bar 210 is prohibited. As a result, even if the area where one contact portion 218b contacts one location on the inner surface of wall portion 21 is small, other contact portions 218b can be brought into contact with other locations on the inner surface of wall portion 21, thereby enhancing the effect of suppressing deformation of conductive member 200b.

[0062] In this modification, the number of contact portions 218b provided on the conductive member 200b is two, but the number of contact portions 218b may be three or more. In Fig. 5, the multiple contact portions 218b are aligned in the Y-axis direction, but the multiple contact portions 218b may also be aligned in a direction perpendicular to the Z-axis direction, such as the X-axis direction.

[0063] [3-3. Variation 3] 6 is a diagram showing a configuration of a conductive member 200c and its surroundings according to Modification 3 of the embodiment. Energy storage device 1 according to this modification includes conductive member 200c connected to energy storage unit 101. Conductive member 200c includes bus bar 210, and bus bar 210 includes first fixing portion 211, second fixing portion 215, and contact portion 218c.

[0064] As shown in FIG. 6 , the contact portion 218c according to this modification is disposed between the electric device 280 and the second fixed portion 215 on the bus bar 210, and in this respect, it differs from the contact portion 218 according to the embodiment. More specifically, the bus bar 210 according to this modification includes a first bus bar 220 and a second bus bar 230, similar to the bus bar 210 according to the embodiment. The second fixed portion 215 provided at one end of the second bus bar 230 is fixed to the wall portion 21, and the electric device 280 is connected to the other end of the second bus bar 230. In this configuration, the contact portion 218c is provided on the second bus bar 230. Even in this case, the contact portion 218c contacts the inner surface of the wall portion 21 at a position different from the second fixed portion 215, thereby suppressing deformation of the conductive member 200c.

[0065] [3-4. Variation 4] 7 is a diagram showing a configuration of a conductive member 200d and its surroundings according to Modification 4 of the embodiment. Energy storage device 1 according to this modification includes conductive member 200d connected to energy storage unit 101. Conductive member 200d includes bus bar 210, and bus bar 210 includes first fixing portion 211, second fixing portion 215, and contact portion 218d.

[0066] As shown in FIG. 7, the contact portion 218d according to this modification is not a bent portion that protrudes toward the wall portion 21, but is provided on the bus bar 210 as a flat portion, and in this respect it differs from the contact portion 218 according to the embodiment.

[0067] More specifically, the wall 21 of the exterior body 10 included in the energy storage device 1 according to this modification has a protrusion 21d that protrudes toward the energy storage unit 101, i.e., in the negative Z-axis direction. The contact portion 218d according to this modification comes into contact with the surface of the protrusion 21d on the inner surface of the wall 21 that faces in the negative Z-axis direction. Even in this case, the contact portion 218d comes into contact with the inner surface of the wall 21 at a position different from the second fixing portion 215, thereby suppressing deformation of the conductive member 200d. That is, the conductive member 200d according to this modification can suppress deformation of the conductive member 200d by utilizing the protrusion 21d on the wall 21 that protrudes toward the energy storage unit 101.

[0068] [3-5. Variation 5] 8 is a diagram showing a configuration of a conductive member 200e and its surroundings according to Modification 5 of the embodiment. The energy storage device 1 according to this modification includes a conductive member 200e connected to an energy storage unit 101. The conductive member 200e includes a bus bar 210e, and the bus bar 210e includes a first fixing portion 211, a second fixing portion 215, and a contact portion 218e.

[0069] As shown in FIG. 8 , the conductive member 200e according to this modification does not include an electric device 280, and the bus bar 210e is realized by a single bus bar. In these respects, the conductive member 200e according to this modification differs from the conductive member 200 according to the embodiment. That is, the conductive member 200e is configured by a single bus bar 210e. Even in this case, the contact portion 218e of the bus bar 210e contacts the inner surface of the wall portion 21 at a position different from the second fixing portion 215, thereby suppressing deformation of the conductive member 200e (i.e., the bus bar 210e).

[0070] [4. Other Modifications] Although the energy storage device 1 according to the embodiment and its modified examples have been described above, the present invention is not limited to the embodiment and its modified examples. In other words, the embodiment disclosed herein is illustrative in all respects and is not restrictive, and the scope of the present invention includes all modifications within the meaning and scope equivalent to the claims.

[0071] It is not essential that the conductive member 200 electrically connects the total positive terminal 120A of the power storage unit 101 to the external terminal 90A. The conductive member 200 may, for example, electrically connect the total negative terminal 120B of the power storage unit 101 to the external terminal 90B.

[0072] Although the conductive member 200 according to the embodiment is elongated in the Y-axis direction, which is the arrangement direction of the energy storage elements 100, this is not essential. The conductive member 200 may be elongated in the X-axis direction or the Z-axis direction. The size and shape of the conductive member 200 may be determined appropriately depending on, for example, the positional relationship between the external terminal 90 and the total positive terminal 120A or the total negative terminal 120B of the energy storage unit 101.

[0073] First fixing portion 211 included in conductive member 200 does not need to be directly fixed to general positive terminal 120A of power storage unit 101. For example, when another bus bar is joined to general positive terminal 120A of power storage unit 101 by welding or the like, first fixing portion 211 may be fixed to the other bus bar, thereby electrically connecting conductive member 200 to power storage unit 101 via the other bus bar. In this case, the other bus bar may be considered to be part of conductive member 200. In other words, bus bar 210 included in conductive member 200 may include first bus bar 220, second bus bar 230, and the other bus bar.

[0074] First fixing portion 211 of bus bar 210 does not need to have the function of electrically connecting to energy storage unit 101. For example, bus bar 210 may have a portion electrically connecting to energy storage unit 101 and a first fixing portion that only has the function of mechanically connecting to energy storage unit 101. In this case, the first fixing portion may be fixed to, for example, bus bar plate 50 or a spacer attached to energy storage element 100. In other words, it is sufficient for the first fixing portion to have at least the function of being fixed to energy storage unit 101.

[0075] The electric device 280 included in the conductive member 200 does not have to be disposed between the first fixing portion 211 and the second fixing portion 215. The electric device 280 may be directly fixed to the external terminal 90A, for example. In this case, the second fixing portion 215 is connected (fixed) to the electric device 280, and thereby fixed to the wall portion 21 via the electric device 280. The same applies to the first fixing portion 211. That is, the electric device 280 may be directly fixed to the total positive terminal 120A of the power storage unit 101. In this case, the first fixing portion 211 is electrically connected to the power storage unit 101 via the electric device 280. When the electric device 280 is disposed at the end of the conduction path in the conductive member 200 in this way, the bus bar 210 may be a single bus bar such as the bus bar 210e shown in FIG. 8.

[0076] At least one of first bus bar 220 and second bus bar 230 included in bus bar 210 may be configured by connecting a plurality of bus bars. For example, first bus bar 220 or second bus bar 230 may be configured by connecting a plurality of bus bars, thereby obtaining first bus bar 220 or second bus bar 230 having a shape corresponding to the internal structure of exterior body 10.

[0077] The wall 21 that the contact portion 218 of the conductive member 200 comes into contact with does not have to be a wall portion in the positive Z-axis direction of the exterior body 10. For example, in cases where the external terminal 90 is disposed on a side wall portion that is a wall portion in the Y-axis direction or the X-axis direction of the exterior body 10, the contact portion 218 may come into contact with the side wall portion. Even in this case, the contact portion 218 comes into contact with the side wall portion of the exterior body 10, thereby suppressing deformation of the conductive member 200.

[0078] The shape of the exterior housing 10 does not have to be a rectangular parallelepiped as shown in Figures 1 and 2. For example, an exterior housing having another shape, such as a cylindrical shape, may be used as the exterior housing that houses the power storage unit 101.

[0079] The various supplementary points regarding the conductive member 200 according to the embodiment described above may be appropriately applied to each of the conductive members 200a to 200e according to Modifications 1 to 5. Configurations constructed by arbitrarily combining the components included in the above embodiment and its modifications are also included within the scope of the present invention. [Industrial Applicability]

[0080] The present invention can be applied to an electricity storage device including an electricity storage element such as a lithium ion secondary battery. [Explanation of symbols]

[0081] 1. Energy storage device 10. Exterior body 21 Wall 21d Convex part 90, 90A, 90B external terminals 100 Energy storage element 101 Energy storage unit 120 terminals 120A total positive terminal 120B total negative terminal 200, 200a, 200b, 200c, 200d, 200e Conductive member 210, 210e busbars 211 First fixed part 215 Second fixed part 218, 218a, 218b, 218c, 218d, 218e contact area 220 First bus bar 230 Second bus bar 280 Electrical Equipment

Claims

1. a power storage unit including a power storage element; an exterior body that houses the electricity storage unit; a conductive member electrically connected to the power storage unit, the exterior body includes a wall portion that is spaced apart from the power storage unit and faces the power storage unit, the conductive member includes a bus bar; The bus bar is a first fixing portion fixed to the power storage unit; a second fixing portion fixed to the wall portion; a contact portion that contacts the inner surface of the wall portion at a position different from the second fixing portion, Energy storage device.

2. the conductive member further includes an electric device connected to the bus bar and disposed between the first fixed portion and the second fixed portion. The power storage device according to claim 1 .

3. The contact portion is disposed between the first fixed portion and the electrical device. The power storage device according to claim 2 .

4. the bus bars include a first bus bar and a second bus bar; the first bus bar includes the first fixing portion at one end of the first bus bar, the electrical device is connected to the other end of the first bus bar, the second bus bar includes the second fixing portion at one end of the second bus bar, The electrical device is connected to the other end of the second bus bar. The electricity storage device according to claim 2 or 3.

5. the contact portion is a part of the bus bar, and is a portion bent so as to protrude toward the wall portion. The electricity storage device according to any one of claims 1 to 3.

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