Fuse device

Abstract

To provide a voltage detection unit and a fuse spatially efficiently.SOLUTION: A first voltage detection device 30A includes a first holder 300A, a first voltage detection unit 310A held by the first holder 300A, and a first conductor 400A attached to the first holder 300A and at least partially functioning as a fuse.SELECTED DRAWING: Figure 6

Description

[Technical Field]

[0001] The present invention relates to a voltage detection device and a battery module. [Background technology]

[0002] A battery module such as a lithium-ion secondary battery may include multiple stacked battery cells. In such a battery module, the multiple battery cells are electrically connected to each other by positive and negative electrode leads extending from the exterior packaging of the battery cells. The battery module may also include a fuse to prevent overcurrent from flowing.

[0003] Patent Document 1 describes an example of a fuse for a battery module. In this example, the width of a portion of a conductive plate housed in a holder is narrower than the width of the other portions of the conductive plate. This allows the portion of the conductive plate to function as a fuse.

[0004] Patent Document 2 describes an example of a fuse for a battery module. In this example, a portion of a bus bar attached to a bus bar frame is thinner than the remaining portion of the bus bar. This allows the portion of the bus bar to function as a fuse. [Prior art documents] [Patent documents]

[0005] [Patent Document 1] Japanese Patent Application Laid-Open No. 2000-182506 [Patent Document 2] Special Publication No. 2020-528650 Summary of the Invention [Problem to be solved by the invention]

[0006] In addition to fuses, battery modules are sometimes provided with voltage detectors for detecting the voltage of the positive or negative electrode leads of battery cells. However, if a voltage detector is provided in addition to a structure for holding a fuse, such as the holder in Patent Document 1 or the bus bar frame in Patent Document 2, the space required for installing the voltage detector and fuses can become relatively large.

[0007] One object of the present invention is to provide a voltage detection section and a fuse in a space-efficient manner. Other objects of the present invention will become apparent from the description of this specification. [Means for solving the problem]

[0008] One aspect of the present invention is A holder; a voltage detection unit held by the holder; a conductor attached to the carrier, at least a portion of which functions as a fuse; The voltage detection device is provided with:

[0009] Another aspect of the present invention is the voltage detection device; a battery cell having a lead portion connected to the voltage detection unit; The battery module includes: [Effects of the Invention]

[0010] According to the above aspect of the present invention, the voltage detection section and the fuse can be provided spatially efficiently. [Brief explanation of the drawings]

[0011] [Figure 1] FIG. 2 is a front perspective view of the battery module according to the embodiment. [Figure 2] FIG. 2 is a perspective view of the battery module according to the embodiment, seen from the rear. [Figure 3] FIG. 2 is a view of FIG. 1 with the container removed. [Figure 4]3 is a view of FIG. 2 with the container removed. [Figure 5] FIG. 2 is a perspective view of the cell stack according to the embodiment, as seen from the front. [Figure 6] 3 is an enlarged view of a position where a first fuse device is provided in the first voltage detection device according to the embodiment. FIG. DETAILED DESCRIPTION OF THE INVENTION

[0012] Hereinafter, embodiments of the present invention will be described with reference to the drawings. In all the drawings, similar components are designated by similar reference numerals, and the description thereof will be omitted as appropriate.

[0013] In this specification, ordinal numbers such as "first," "second," and "third" are used merely to distinguish between similarly named configurations, unless otherwise specified, and do not imply any particular characteristics (e.g., order or importance) of the configurations.

[0014] Fig. 1 is a perspective view of a battery module 50 according to an embodiment, as seen from the front. Fig. 2 is a perspective view of a battery module 50 according to an embodiment, as seen from the rear. Fig. 3 is a view of Fig. 1 from which a housing body 20 has been removed. Fig. 4 is a view of Fig. 2 from which a housing body 20 has been removed. Fig. 5 is a perspective view of a cell stack 10 according to an embodiment, as seen from the front.

[0015] 1 to 5, the arrows indicating the first direction X, the second direction Y, and the third direction Z indicate that the direction from the base end of the arrow to the tip end is the positive direction of the arrow, and the direction from the tip end of the arrow to the base end is the negative direction of the arrow. The first direction X indicates a direction parallel to the horizontal direction perpendicular to the vertical direction. Specifically, the first direction X indicates the front-to-rear direction of the battery module 50. The positive direction of the first direction X is the direction from the front to the rear of the battery module 50. The negative direction of the first direction X is the direction from the rear to the front of the battery module 50. The second direction Y indicates a direction perpendicular to the vertical direction and the first direction X. The second direction Y indicates the left-to-right direction of the battery module 50. The positive direction of the second direction Y is the direction from the right to the left of the battery module 50 when viewed from the front of the battery module 50. The negative direction of the second direction Y is the direction from the left to the right of the battery module 50 when viewed from the front of the battery module 50. The third direction Z indicates a direction parallel to the vertical direction. The positive direction of the third direction Z is the direction from below to above the battery module 50. The negative direction of the third direction Z is the direction from above to below the battery module 50.

[0016] The relationship between the first direction X, the second direction Y, the third direction Z, the vertical direction, and the horizontal direction is not limited to the above example. For example, the battery module 50 may be arranged so that the first direction X or the second direction Y is parallel to the vertical direction.

[0017] Hereinafter, unless otherwise specified, "right" and "left" refer to the right and left, respectively, when viewed from the front of the battery module 50.

[0018] In this embodiment, the battery module 50 is mounted on a mobile object such as an automobile, etc. However, the use of the battery module 50 is not limited to this example.

[0019] The battery module 50 includes a cell stack 10, a housing 20, a first voltage detection device 30A, and a second voltage detection device 30B. The first voltage detection device 30A includes a first fuse device 40A. The second voltage detection device 30B includes a second fuse device 40B. As will be described later with reference to FIG. 6, the first fuse device 40A includes a fuse electrically connected to a terminating positive electrode lead 112T. The second fuse device 40B includes a fuse electrically connected to a terminating negative electrode lead 114T.

[0020] 5, the cell stack 10 includes a plurality of cell groups 100G stacked in the second direction Y. Each cell group 100G includes a plurality of battery cells 100 stacked in the second direction Y. Each battery cell 100 includes an outer casing 102, a positive electrode lead 112, and a negative electrode lead 114.

[0021] In this embodiment, each cell group 100G includes two battery cells 100. However, each cell group 100G may include three or more battery cells 100. Note that in the cell stack 10, multiple cell groups 100G may not be connected in series, but multiple battery cells 100 may be connected in series. In other words, the number of battery cells 100 included in a cell group 100G may be only one.

[0022] Each battery cell 100 is placed substantially vertically. The fact that the battery cells 100 are placed substantially vertically does not necessarily mean that the battery cells 100 are placed strictly vertically. The fact that the battery cells 100 are placed substantially vertically means that the battery cells 100 may be tilted obliquely from the third direction Z as long as the operation of the battery module 50 is not impaired.

[0023] As shown in FIGS. 3 and 4 , a plurality of adhesive members 104 are disposed on the upper surface of the cell stack 10. Each adhesive member 104 is, for example, a cured liquid resin. In this embodiment, the plurality of adhesive members 104 are disposed in a regular pattern. Specifically, the plurality of adhesive members 104 extend parallel to the second direction Y and are aligned parallel to the first direction X. An insulating sheet (not shown) is disposed above the plurality of adhesive members 104. A sixth cover member 260 (described later) is disposed above the insulating sheet (not shown). The layout of the adhesive members 104 is not limited to the layout according to this embodiment. For example, the adhesive members 104 may be disposed across the entire upper surface of the cell stack 10. Alternatively, the plurality of adhesive members 104 may be disposed irregularly, or may be aligned in a pattern different from that shown in FIGS. 3 and 4 . Adhesive members are also disposed on the lower surface of the cell stack 10 in the same manner as on the upper surface of the cell stack 10.

[0024] The exterior packaging 102 accommodates a positive electrode, a negative electrode, and a separator (not shown) together with an electrolyte (not shown). In one example, the positive electrode, the negative electrode, and the separator are stacked in the second direction Y within the exterior packaging 102. Alternatively, the positive electrode, the negative electrode, and the separator may be wound within the exterior packaging 102.

[0025] The positive electrode lead 112 is drawn out in a substantially horizontal direction from one of the front end and the rear end of the exterior material 102. The positive electrode lead 112 is electrically connected to a positive electrode inside the exterior material 102. In one example, the positive electrode lead 112 is made of a metal such as aluminum. The positive electrode lead 112 being drawn out in a substantially horizontal direction does not necessarily mean that the positive electrode lead 112 is drawn out in a strictly horizontal direction. The positive electrode lead 112 being drawn out in a substantially horizontal direction means that the positive electrode lead 112 may be drawn out in a direction deviated from the horizontal direction as long as the operation of the battery module 50 is not impaired.

[0026] The negative electrode lead 114 is drawn out in a substantially horizontal direction from the other of the front end and the rear end of the exterior material 102. The negative electrode lead 114 is electrically connected to a negative electrode inside the exterior material 102. In one example, the negative electrode lead 114 is made of a metal different from the metal constituting the positive electrode lead 112, such as copper. The negative electrode lead 114 being drawn out in a substantially horizontal direction does not necessarily mean that the negative electrode lead 114 is drawn out in a strictly horizontal direction. The negative electrode lead 114 being drawn out in a substantially horizontal direction means that the negative electrode lead 114 may be drawn out in a direction deviated from the horizontal direction as long as the operation of the battery module 50 is not impaired.

[0027] When each cell group 100G includes multiple battery cells 100, these multiple battery cells 100 are connected in parallel. Specifically, the multiple battery cells 100 included in each cell group 100G are stacked in the second direction Y. The positive electrode leads 112 of the multiple battery cells 100 included in each cell group 100G are bundled and connected to each other in the second direction Y. The negative electrode leads 114 of the multiple battery cells 100 included in each cell group 100G are bundled and connected to each other in the second direction Y. Adjacent battery cells 100 may be stacked via an adhesive member. Examples of adhesive members include double-sided tape and a hardening liquid resin.

[0028] The multiple cell groups 100G are connected in series via lead portions 110. The lead portion 110 includes multiple positive electrode leads 112 for one of the cell groups 100G adjacent to each other in the second direction Y, and multiple negative electrode leads 114 for the other of the cell groups 100G adjacent to each other in the second direction Y. The multiple positive electrode leads 112 and negative electrode leads 114 included in the lead portion 110 are joined to each other by a joining method such as laser welding, ultrasonic bonding, resistance welding, or adhesive bonding. When the positive electrode lead 112 and the negative electrode lead 114 are made of different materials, laser welding is preferred among these joining methods from the viewpoints of high joining reliability and reduced number of parts. The lead portion 110 is folded back between the cell groups 100G adjacent to each other in the second direction Y. As a result, the multiple lead portions 110 are aligned in the second direction Y at the front of the cell stack 10. Furthermore, at the rear of the cell stack 10, a plurality of lead portions 110 are arranged in the second direction Y.

[0029] In this embodiment, as shown in Fig. 3 , at the joint between the multiple positive electrode leads 112 and the multiple negative electrode leads 114 of each lead portion 110 located at the front of the cell stack 10, the multiple negative electrode leads 114 are located forward of the multiple positive electrode leads 112. Also, as shown in Fig. 4 , at the joint between the multiple positive electrode leads 112 and the multiple negative electrode leads 114 of each lead portion 110 located at the rear of the cell stack 10, the multiple positive electrode leads 112 are located rear of the multiple negative electrode leads 114. Note that when the multiple positive electrode leads 112 are located forward of the multiple negative electrode leads 114 at the front of the cell stack 10, the material of a first tip portion 314A (described later) is preferably the same as the material of the positive electrode lead 112.

[0030] In this embodiment, as shown in FIG. 3 , the positive electrode leads 112 included in one end cell group 100G of the multiple cell groups 100G connected in series are located on the right front side of the cell stack 10. Hereinafter, as needed, the positive electrode leads 112 included in one end cell group 100G of the multiple cell groups 100G connected in series will be referred to as a terminal positive electrode lead 112T. Also, as shown in FIG. 4 , the negative electrode leads 114 included in the other end cell group 100G of the multiple cell groups 100G connected in series are located on the left rear side of the cell stack 10. Hereinafter, as needed, the negative electrode leads 114 included in the other end cell group 100G of the multiple cell groups 100G connected in series will be referred to as a terminal negative electrode lead 114T.

[0031] The structure of the cell stack 10 is not limited to the structure according to this embodiment. For example, the terminal negative electrode lead 114T may be located on the left front side of the cell stack 10 instead of the left rear side. In this example, both the terminal positive electrode lead 112T and the terminal negative electrode lead 114T are located on the front side. Whether the terminal negative electrode lead 114T is located on the left front side or the left rear side of the cell stack 10 can be adjusted depending on the number of cell groups 100G stacked in the second direction Y.

[0032] In this embodiment, as shown in FIG. 3 , the front surfaces of the joints of the positive electrode lead 112 and the negative electrode lead 114 of each lead portion 110 located at the front of the cell stack 10 are substantially parallel to a direction perpendicular to the first direction X. The fact that the front surfaces of the joints are substantially parallel to a direction perpendicular to the first direction X does not necessarily mean that the front surfaces of the joints are strictly parallel to the direction perpendicular to the first direction X. The fact that the front surfaces of the joints are substantially parallel to a direction perpendicular to the first direction X also means that the front surfaces of the joints are slightly deformed from a state where they are parallel to the direction perpendicular to the first direction X, as long as the function of the lead portion 110 is not impaired. In this embodiment, the first voltage detection unit 310A (described later) can be more easily joined to the front surfaces of the lead portions 110 than when the front surfaces of the joints are curved. In another example different from this embodiment, the front surfaces of the joints described above may be curved.

[0033] In this embodiment, as shown in FIG. 4, the rear surface of the joint between the positive electrode lead 112 and the negative electrode lead 114 of each lead portion 110 located at the rear of the cell stack 10 is substantially parallel to a direction perpendicular to the first direction X, similar to the front surface of the joint between the positive electrode lead 112 and the negative electrode lead 114 of each lead portion 110 located at the front of the cell stack 10.

[0034] The housing 20 houses the cell stack 10, the first voltage detection device 30A, and the second voltage detection device 30B. The housing 20 has a first cover member 210, a second cover member 220, a third cover member 230, a fourth cover member 240, a fifth cover member 250, and a sixth cover member 260. In this embodiment, the first cover member 210, the second cover member 220, the third cover member 230, the fourth cover member 240, the fifth cover member 250, and the sixth cover member 260 are made of a metal containing aluminum as a main component, for example. However, the materials constituting the first cover member 210, the second cover member 220, the third cover member 230, the fourth cover member 240, the fifth cover member 250, and the sixth cover member 260 are not limited to this example.

[0035] The first cover member 210 covers the front side of the cell stack 10 and the first voltage detection device 30A. The second cover member 220 covers the rear side of the cell stack 10 and the second voltage detection device 30B. The third cover member 230 covers the right side of the cell stack 10. The fourth cover member 240 covers the left side of the cell stack 10. The fifth cover member 250 covers the bottom side of the cell stack 10. The sixth cover member 260 covers the top side of the cell stack 10.

[0036] As shown in FIGS. 1 and 2, a "+" mark is provided on the front right side of the upper surface of the sixth cover member 260. A "-" mark is provided on the rear left side of the upper surface of the sixth cover member 260. The "+" mark indicates that the terminal positive lead 112T shown in FIG. 3 is located at the position marked with the "+" mark. The "-" mark indicates that the terminal negative lead 114T shown in FIG. 4 is located at the position marked with the "-" mark. Therefore, even if the cell stack 10 is barely visible from outside the housing 20, a user of the battery module 50 can determine the positions of the terminal positive lead 112T and the terminal negative lead 114T from the "+" mark and the "-" mark.

[0037] The first voltage detecting device 30A has a first holding body 300A, a plurality of first voltage detecting parts 310A, a plurality of first voltage detecting lines 320A, and a first connector 330A.

[0038] The first holder 300A is provided in front of the cell stack 10. The first holder 300A is an insulator. As the insulator, a polypropylene-based resin or a resin having equivalent or greater hardness and insulating properties is used. The first holder 300A is attached to the housing 20 by mechanical joining such as a snap fit or screws.

[0039] Each first voltage detection portion 310A has a first base end portion 312A, a first tip end portion 314A, and a first connection portion 316A.

[0040] The first base end 312A is supported movably in the first direction X along a first support shaft 318A provided on the first holder 300A. As a result, each first voltage detection unit 310A is held by the first holder 300A. The first support shaft 318A passes through a through hole provided in the first base end 312A in the first direction X. The diameter of the front end of the first support shaft 318A in the direction perpendicular to the first direction X is larger than the diameter of the through hole in the first base end 312A in the direction perpendicular to the first direction X. Therefore, the first base end 312A is prevented from slipping off the first support shaft 318A toward the front of the first support shaft 318A.

[0041] In this embodiment, when viewed from the front of the cell stack 10, the first tip portion 314A is positioned offset in the horizontal and vertical directions from the first base end portion 312A. Specifically, when viewed from the front of the cell stack 10, the first tip portion 314A is positioned to the lower right of the first base end portion 312A. As a result, a gap is provided to the right of the first base end portion 312A and above the first tip portion 314A, exposing a portion of the front surface of the lead portion 110 toward the front. Therefore, at least a portion of a joint, such as a laser welded joint between the positive electrode lead 112 and the negative electrode lead 114, can be provided in a region of the lead portion 110 that overlaps the gap in the first direction X. In other words, the joint of the lead portion 110 needs not to overlap the first tip portion 314A in the first direction X. Therefore, in this embodiment, the vertical length of the joint portion of the lead portion 110 can be made longer than in the case where, for example, the first tip portion 314A is not shifted downward relative to the first base end 312A and is positioned to the right of the first base end 312A. Therefore, in this embodiment, the connection between the positive electrode lead 112 and the negative electrode lead 114 in the lead portion 110 can be made better than in the above-mentioned case.

[0042] Furthermore, in this embodiment, the first tip portion 314A is positioned offset with respect to the first base end portion 312A toward the side where the lead portion 110 is positioned. Therefore, in this embodiment, compared to when the position of the first base end portion 312A in the first direction X and the position of the first tip portion 314A in the first direction X are aligned in the first direction X, it is possible to more easily bring the first tip portion 314A closer to the lead portion 110 and to more easily connect the first tip portion 314A to the lead portion 110. Furthermore, in this embodiment, it is possible to increase the range of motion of the first base end portion 312A in the first direction X compared to the above-described case.

[0043] The first connection portion 316A protrudes downward from the first base end portion 312A. One end of the first voltage detection line 320A is connected to the first connection portion 316A. The first connection portion 316A may be integral with the first base end portion 312A, for example. As shown in FIG. 6 (described later), in this embodiment, the first connection portion 316A has two first barrels 316aA to which one end of the first voltage detection line 320A is crimped. The two first barrels 316aA are aligned vertically. One end of the first voltage detection line 320A enters the internal space of the two first barrels 316aA from below, substantially parallel to the vertical direction, and is crimped by the two first barrels 316aA. As a result, one end of the first voltage detection line 320A is fixed to the first connection portion 316A. However, the method for fixing one end of the first voltage detection line 320A to the first connection portion 316A is not limited to the method according to this embodiment. For example, only one first barrel 316aA may be provided for each first connection portion 316A. Alternatively, one end of the first voltage detection line 320A may be soldered to the first connection portion 316A.

[0044] The shape of the first voltage detection unit 310A is not limited to the shape according to this embodiment, as long as the first tip end portion 314A does not overlap in the first direction X with the joint portion between the positive electrode lead 112 and the negative electrode lead 114 of the lead portion 110. For example, when viewed from the front of the cell stack 10, the gap does not need to be provided to the right of the first base end portion 312A and above the first tip end portion 314A. Furthermore, the position of the first base end portion 312A in the first direction X and the position of the first tip end portion 314A in the first direction X may be aligned.

[0045] Each of the multiple first voltage detection units 310A is connected to a corresponding one of the multiple lead portions 110 at the front of the cell stack 10. Specifically, each first tip portion 314A is joined to the corresponding lead portion 110 at the front of the cell stack 10 by a joining method such as laser welding. In this embodiment, the rear surface of the first tip portion 314A is joined to the front surface of the joint portion of the lead portion 110 where the positive electrode lead 112 and the negative electrode lead 114 are joined. The first tip portion 314A is preferably made of the same material as the portion of the lead portion 110 that contacts the first tip portion 314A. In this embodiment, the first tip portion 314A contacts the negative electrode lead 114. In this example, it is easier to join the first tip portion 314A to the negative electrode lead 114 compared to when the first tip portion 314A is made of a different material from the negative electrode lead 114. In another example, first tip 314A may be made of a different material than the portion of lead 110 that contacts first tip 314A.

[0046] Each of the multiple first voltage detection lines 320A electrically connects each of the multiple first voltage detection units 310A to the first connector 330A. As described above, one end of each first voltage detection line 320A is connected to the first connection portion 316A. The other end of each first voltage detection line 320A is connected to the first connector 330A. In this embodiment, a portion of each first voltage detection line 320A is drawn from the first connection portion 316A to the space below the first frame 340A via a notch 350A provided in the first frame 340A, which will be described later. The notch 350A is provided in a corner of the first frame 340A between a second edge portion 344A and a third edge portion 346A, which will be described later. Another portion of each first voltage detection wire 320A passes through a space between adjacent first frames 340A in an area shifted to the right from the center of the first holding body 300A, and is drawn out from the space below the plurality of first frames 340A to a first connector 330A located above the plurality of first frames 340A. The positions of the first voltage detection unit 310A, the routing of the first voltage detection wire 320A, the position of the notch 350A, and the position of the first connector 330A are not limited to the example according to this embodiment.

[0047] In this embodiment, at least a portion of the region of the first voltage detection line 320A located between the first connection portion 316A and the notch 350A is flexible. When the first base end portion 312A is moved in the first direction X along the first support shaft 318A, the first voltage detection line 320A may come into contact with the first holder 300A or the first frame 340A near the notch 350A. Even in such a case, the first base end portion 312A can be moved in the first direction X along the first support shaft 318A by bending at least the portion of the first voltage detection line 320A.

[0048] The first holder 300A has multiple first frames 340A. The first frames 340A are insulators. Examples of insulators include polypropylene-based resins and resins with equivalent or greater hardness and insulating properties. Each of the multiple first frames 340A surrounds each of the multiple lead portions 110 and each of the multiple first voltage detection portions 310A. Therefore, the lead portions 110 and the first voltage detection portions 310A can be protected from external impacts by the first frames 340A. Each of the first frames 340A does not have to be positioned over the entire area surrounding each of the lead portions 110 and each of the first voltage detection portions 310A. Each of the first frames 340A may be positioned over at least a portion of the area surrounding each of the lead portions 110 and each of the first voltage detection portions 310A. The first holder 300A may be composed of a single member or multiple members combined together.

[0049] Each first frame 340A includes a first edge 342A, a second edge 344A, a third edge 346A, and a fourth edge 348A. The first edge 342A extends vertically to the right of the lead 110 and first voltage detection unit 310A enclosed by each first frame 340A. The second edge 344A extends vertically to the left of the lead 110 and first voltage detection unit 310A enclosed by each first frame 340A. The third edge 346A extends horizontally below the lead 110 and first voltage detection unit 310A enclosed by each first frame 340A. The fourth edge 348A extends horizontally above the lead 110 and first voltage detection unit 310A enclosed by each first frame 340A.

[0050] The shape of the first frame 340A is not limited to the shape according to this embodiment. For example, the first frame 340A may not have one of the first edge 342A and the second edge 344A. Furthermore, the first frame 340A may not have at least one of the third edge 346A and the fourth edge 348A.

[0051] In this embodiment, at least a portion of the insulator constituting each first frame 340A is located between the first voltage detection unit 310A surrounded by each first frame 340A and a lead 110 different from the lead 110 connected to the first voltage detection unit 310A. Therefore, in this embodiment, electrical insulation can be ensured between the first voltage detection unit 310A surrounded by each first frame 340A and the lead 110 different from the lead 110 connected to the first voltage detection unit 310A.

[0052] Specifically, except for the first frame 340A located at the rightmost end, at least a portion of the insulator constituting the first edge 342A is located between the first voltage detection unit 310A located on the left side of the first edge 342A and the lead 110 located on the right side of the first edge 342A. Therefore, compared to when the first edge 342A is not provided, it is possible to ensure electrical insulation between the first voltage detection unit 310A located on the left side of the first edge 342A and the lead 110 located on the right side of the first edge 342A.

[0053] Furthermore, except for the first frame 340A located at the leftmost end, at least a portion of the insulator constituting the second edge 344A is located between the first voltage detection unit 310A located on the right side of the second edge 344A and the lead 110 located on the left side of the second edge 344A. Therefore, compared to when the second edge 344A is not provided, it is possible to ensure electrical insulation between the first voltage detection unit 310A located on the right side of the second edge 344A and the lead 110 located on the left side of the second edge 344A.

[0054] In this embodiment, at least a portion of the insulator constituting each first frame 340A is located between different lead portions 110. Specifically, at least a portion of the insulator constituting each first frame 340A is located between adjacent lead portions 110. Therefore, electrical insulation between different lead portions 110 can be ensured compared to a case where at least a portion of the insulator constituting each first frame 340A is not located between different lead portions 110.

[0055] Specifically, except for the first frame 340A located at the rightmost end, at least a portion of the insulator constituting the first edge 342A is located between the lead 110 located on the left side of the first edge 342A and the lead 110 located on the right side of the first edge 342A. Therefore, compared to when the first edge 342A is not provided, it is possible to ensure electrical insulation between the lead 110 located on the left side of the first edge 342A and the lead 110 located on the right side of the first edge 342A.

[0056] Furthermore, except for the first frame 340A located at the leftmost end, at least a portion of the insulator constituting the second edge 344A is located between the lead 110 located on the right side of the second edge 344A and the lead 110 located on the left side of the second edge 344A. Therefore, compared to when the second edge 344A is not provided, it is possible to ensure electrical insulation between the lead 110 located on the right side of the second edge 344A and the lead 110 located on the left side of the second edge 344A.

[0057] The surface of the first frame 340A facing the positive side in the first direction X may be provided with an insulating protrusion that protrudes toward the positive side in the first direction X. At least a portion of this protrusion is located between adjacent leads 110 in the second direction Y. For example, the protrusion is provided on the positive side in the first direction X of a first edge 342A of the left first frame 340A of adjacent first frames 340A in the second direction Y, and on the positive side in the first direction X of a second edge 344A of the right first frame 340A of adjacent first frames 340A in the second direction Y. In this example, when adjacent leads 110 in the second direction Y are displaced in the second direction Y due to an external impact or other factor, the lead 110 hits the protrusion. This prevents the adjacent leads 110 from colliding with each other in the second direction Y. The length of the protrusion is not particularly limited, but may be set to a length that prevents the leads 110 adjacent to each other in the second direction Y from colliding with each other. In addition, the position at which the protrusion is provided is not limited to the example described above.

[0058] In this embodiment, at least a portion of the insulator constituting each first frame 340A is located between at least one lead 110 and at least a portion of the housing 20 that has conductivity. Therefore, in this embodiment, electrical insulation between at least one lead 110 and at least a portion of the housing 20 that has conductivity can be ensured.

[0059] Specifically, at least a portion of the third edge 346A is located below the lead 110 surrounded by each first frame 340A. In this embodiment, the front end of the fifth cover member 250 is located below the lower end of the lead 110. If the fifth cover member 250 is conductive, contact between the lower end of the lead 110 and the front end of the fifth cover member 250 may result in a short circuit between the lead 110 and the fifth cover member 250. In contrast, in this embodiment, at least a portion of the insulator constituting the third edge 346A is located between the lower end of the lead 110 and the front end of the fifth cover member 250. Therefore, compared to when the third edge 346A is not provided, a short circuit between the lead 110 and the fifth cover member 250 can be suppressed.

[0060] In the above example, it has been described that the third edge 346A ensures electrical insulation between the lower end of the lead 110 and the front end of the fifth cover member 250. However, ensuring electrical insulation between the lead 110 and the housing 20 by the first frame 340A is not limited to the above example. For example, the fourth edge 348A can ensure electrical insulation between the upper end of the lead 110 and the front end of the sixth cover member 260. Furthermore, the first edge 342A of the first frame 340A located at the rightmost position among the plurality of first frames 340A can ensure electrical insulation between the right end of the lead 110 located at the rightmost position among the plurality of leads 110 and the front end of the third cover member 230. Furthermore, the second edge 344A of the first frame 340A located at the leftmost position among the plurality of first frames 340A can ensure electrical insulation between the left end of the lead 110 located at the leftmost position among the plurality of leads 110 and the front end of the fourth cover member 240.

[0061] In this embodiment, between the lead portions 110 adjacent in the second direction Y, there are located a second edge portion 344A of the first frame 340A surrounding the right lead portion 110 of the lead portions 110 adjacent in the second direction Y, and a first edge portion 342A of the first frame 340A surrounding the left lead portion 110 of the lead portions 110 adjacent in the second direction Y. Therefore, the distance in the second direction Y between the lead portions 110 adjacent in the second direction Y needs to be greater than the distance in the second direction Y between the second edge portion 344A and the first edge portion 342A located between the lead portions 110 adjacent in the second direction Y. The distance in the second direction Y between the lead portions 110 adjacent in the second direction Y increases as the number of battery cells 100 included in the cell group 100G increases. Therefore, it is easier to increase the distance in the second direction Y between adjacent lead portions 110 in the second direction Y when the cell group 100G includes multiple battery cells 100 than when the cell group 100G includes only one battery cell 100.

[0062] Similar to the first voltage detecting device 30A, the second voltage detecting device 30B includes a second holding body 300B, a plurality of second voltage detecting parts 310B, a plurality of second voltage detecting lines 320B, and a second connector 330B.

[0063] The second holder 300B is provided behind the cell stack 10. Each of the second voltage detection units 310B is connected to a corresponding one of the lead portions 110 at the rear of the cell stack 10. In this embodiment, the surface of each second voltage detection unit 310B facing the negative direction in the first direction X is joined to the surface of the lead portion 110 at the positive direction in the first direction X of the joint between the positive electrode lead 112 and the negative electrode lead 114. Each of the second voltage detection lines 320B electrically connects each of the second voltage detection units 310B to the second connector 330B. The second holder 300B is provided with a plurality of second frames 340B. Similar to the plurality of first frames 340A, each of the second frames 340B surrounds each of the lead portions 110 at the rear of the cell stack 10 and each of the second voltage detection units 310B.

[0064] FIG. 6 is an enlarged view of a position where a first fuse device 40A is provided in a first voltage detecting device 30A according to the embodiment.

[0065] The first fuse device 40A includes a first base 302A, a first conductor 400A, a first fixture 432A, a second fixture 434A, and a first wire 440A.

[0066] The first base 302A includes the right end portion of the first holding body 300 A. In this embodiment, the first base 302A includes the two rightmost first frames 340A among the plurality of first frames 340A.

[0067] The first conductor 400A is provided on the first base 302A. The first conductor 400A is made of, for example, a metal. The first conductor 400A functions as a bus bar electrically connected to the terminal positive lead 112T.

[0068] The first conductor 400A includes a plurality of extensions extending in different directions, at least a portion of at least one of which is held by the first base 302A.

[0069] Specifically, the first conductor 400A includes a first extension 410A extending horizontally and a second extension 420A extending vertically. The second extension 420A extends downward from the right end of the first extension 410A. The first extension 410A and the second extension 420A are integrally formed. However, the first conductor 400A may be formed by, for example, combining a metal that will become the first extension 410A with a metal that will become the second extension 420A. However, the method for forming the first conductor 400A is not limited to this example. Furthermore, the shape of the first conductor 400A is not limited to the shape according to this embodiment. For example, the first conductor 400A may not include the second extension 420A.

[0070] The first extension body 410A includes a first wide portion 412A, a narrow portion 414A, and a second wide portion 416A. The left end of the narrow portion 414A is connected to the right end of the first wide portion 412A. The right end of the narrow portion 414A is connected to the left end of the second wide portion 416A.

[0071] The first wide portion 412A functions as a terminal for electrically connecting to another battery module (not shown). A fastening hole 450A is provided at the left end of the first wide portion 412A. A fastening tool (not shown) is fixed to the fastening hole 450A to secure, for example, a bus bar (not shown) electrically connected to another battery module. In this embodiment, the periphery of the fastening hole 450A in the first wide portion 412A is positioned higher than the narrow portion 414A. However, the periphery of the fastening hole 450A in the first wide portion 412A may be positioned at the same height as the narrow portion 414A.

[0072] The narrow portion 414A functions as a fuse. The width of the narrow portion 414A in the first direction X is narrower than both the width of the first wide portion 412A in the first direction X and the width of the second wide portion 416A in the first direction X. Therefore, the cross-sectional area of the narrow portion 414A perpendicular to the second direction Y is smaller than both the cross-sectional area of the first wide portion 412A perpendicular to the second direction Y and the cross-sectional area of the second wide portion 416A perpendicular to the second direction Y. Therefore, when an overcurrent flows through the first conductor 400A, the narrow portion 414A is more likely to melt than the first wide portion 412A and the second wide portion 416A.

[0073] In this embodiment, the narrow width portion 414A is attached to the first holding body 300A. Therefore, the first voltage detection unit 310A and the fuse can be provided more spatially efficiently than when a structure for holding the fuse is provided separately from the first holding body 300A.

[0074] Furthermore, in this embodiment, the battery module 50 can be made smaller than when a tubular fuse tube is used as the fuse. Specifically, when a tubular fuse is used, the higher the energy of the battery module 50, the larger the tubular fuse becomes. Therefore, in a battery module 50 with a relatively high energy, the space required to install the tubular fuse is relatively large. In contrast, when a portion of the first conductor 400A functions as a fuse, the space required to install the fuse can be made smaller than when a tubular fuse is used.

[0075] In the present embodiment, the narrow portion 414A extends in the same direction as the extension direction of the first wide portion 412A. That is, the first wide portion 412A and the narrow portion 414A extend in the second direction Y. If the narrow portion 414A were provided in the second extension body 420A and extended in a direction perpendicular to the extension direction of the first wide portion 412A, it would be difficult to join the narrow portion 414A provided in the second extension body 420A to the terminal positive electrode lead 112T. In contrast, in the present embodiment, it is not necessary to provide the narrow portion 414A in the second extension body 420A. Therefore, in the present embodiment, the length in the third direction Z of the joint portion between the second extension body 420A and the terminal positive electrode lead 112T can be made longer than in the above-described case. Furthermore, in the present embodiment, the length in the second direction Y of the narrow portion 414A can be more easily adjusted than in the above-described case. Furthermore, in this embodiment, the narrow width portion 414A and the terminal positive electrode lead 112T can be provided farther apart than in the above-described case. Therefore, in this embodiment, the influence of heat generated by the narrow width portion 414A on the terminal positive electrode lead 112T can be suppressed compared to the above-described case.

[0076] A first space 402A that defines the narrow width portion 414A is provided in front of the narrow width portion 414A of the first extension body 410A. In this embodiment, the first space 402A is formed by punching out, by press working, a portion of the conductor that constitutes the first extension body 410A in front of the portion that becomes the narrow width portion 414A.

[0077] The first elongated body 410A does not have a space defining the narrow width portion 414A behind the narrow width portion 414A. However, the method for forming the narrow width portion 414A is not limited to the method according to this embodiment. For example, the first space 402A may be provided behind the narrow width portion 414A. Alternatively, the first space 402A may be provided both in front of and behind the narrow width portion 414A. Furthermore, the first space 402A may be formed by a through-hole that penetrates the first elongated body 410A in the vertical direction. In this case, portions of the first elongated body 410A on both sides of the first space 402A in the first direction X become the narrow width portions 414A that function as fuses.

[0078] When the narrow portion 414A is formed by press working, as in the present embodiment, it is preferable that the space defining the narrow portion 414A be provided on only one of both sides of the first extension 410A in the first direction X. In this case, it is not necessary to punch out the rear portion of the conductor constituting the first extension 410A that will become the narrow portion 414A by press working. This embodiment is compared with a case in which both the front and rear portions of the conductor constituting the first extension 410A that will become the narrow portion 414A are punched out by press working. In the above case, compared to the present embodiment, the front and rear portions of the portion that will become the narrow portion 414A must be punched out simultaneously or separately, which increases the mechanical load applied to the narrow portion 414A, which is the narrowest portion of the first extension 410A, during press working. Therefore, in the above case, compared to the present embodiment, it is necessary to widen the width of the narrow portion 414A in the first direction X in order to prevent breakage of the narrow portion 414A. In contrast to this, in this embodiment, the width of the narrow width portion 414A in the first direction X can be made narrower than in the above-described case, and the degree of freedom in the dimensions of the narrow width portion 414A can be increased.

[0079] The method for forming the narrow portion 414A is not limited to press processing. The narrow portion 414A may be formed, for example, by laser processing. When the narrow portion 414A is formed by laser processing, the space defining the narrow portion 414A may be provided on only one of both sides of the first extension body 410A in the first direction X, or may be provided on both sides of the first extension body 410A in the first direction X.

[0080] A second space 304A is provided below the narrow portion 414A. The second space 304A is defined by a recess provided in the upper surface of the first base 302A on which the first extension body 410A is placed. In this embodiment, if an overcurrent flows through the first conductor 400A and the narrow portion 414A melts, the melted narrow portion 414A can fall toward the second space 304A. Therefore, according to this embodiment, the likelihood of the narrow portion 414A melting can be increased compared to when the lower surface of the narrow portion 414A is in contact with the upper surface of the first base 302A.

[0081] In the present embodiment, at least a portion of the narrow portion 414A is located above at least one of the positive electrode lead 112 and the negative electrode lead 114. Furthermore, at least a portion of the first base 302A is located between at least one of the positive electrode lead 112 and the negative electrode lead 114 and at least a portion of the narrow portion 414A in the third direction Z. Specifically, a portion of the first base 302A that defines the bottom of the recess is located between at least one of the positive electrode lead 112 and the negative electrode lead 114 and at least a portion of the narrow portion 414A in the third direction Z. This prevents the melted narrow portion 414A from coming into contact with the positive electrode lead 112 or the negative electrode lead 114 located below the narrow portion 414A.

[0082] A portion of the first base 302A located above at least one of the positive electrode lead 112 and the negative electrode lead 114 may be heat-resistant. For example, a heat-resistant layer may be provided on the bottom surface of the recess of the first base 302A. The heat-resistant layer may be made of metal or an inorganic material such as ceramic or glass. By providing the heat-resistant layer, it is possible to more reliably prevent the molten narrow portion 414A from melting the main body of the first base 302A and coming into contact with the positive electrode lead 112, the negative electrode lead 114, or the first wiring 440A.

[0083] The first wide portion 412A is fixed to the first base 302A by a first fastener 432A. In this embodiment, the first fastener 432A is a screw that penetrates the first wide portion 412A in the vertical direction and is inserted into a portion of the first base 302A that is positioned below the first wide portion 412A. A through-hole is provided in the first wide portion 412A, through which the shaft of the first fastener 432A can be inserted in the vertical direction. The first fastener 432A may be a fastener other than a screw, such as a screw or a bolt.

[0084] The second wide portion 416A is fixed to the first base 302A by a second fastener 434A. In this embodiment, the second fastener 434A is a screw that penetrates the second wide portion 416A vertically and is inserted into a portion of the first base 302A that is positioned below the second wide portion 416A. A through-hole is provided in the second wide portion 416A through which the shaft of the second fastener 434A can be inserted vertically. The second fastener 434A may be a fastener other than a screw, such as a screw or a bolt.

[0085] In this embodiment, fasteners such as first fastener 432A and second fastener 434A are detachable from first conductor 400A. Therefore, when first conductor 400A needs to be replaced due to melting of narrow portion 414A or the like, first conductor 400A can be replaced with a new first conductor 400A by removing fasteners such as first fastener 432A and second fastener 434A.

[0086] The method for fixing the first conductor 400A to the first base 302A is not limited to the above example. For example, at least a portion of the first conductor 400A may be joined to at least a portion of the first base 302A via a mechanical joint such as a snap fit.

[0087] In this embodiment, both the first wide portion 412A and the second wide portion 416A are fixed to the first base 302A by the first fastener 432A and the second fastener 434A. In this case, compared to when at least one of the first wide portion 412A and the second wide portion 416A is not fixed to the first base 302A, the application of a force that would break the narrow portion 414A to the narrow portion 414A can be suppressed. For example, a force that would break the narrow portion 414A occurs when a fastener (not shown) is fastened to the fastening hole 450A when attaching a bus bar (not shown) to the first wide portion 412A to electrically connect the battery module 50 to another battery module (not shown). This is because the fastening hole 450A and the narrow portion 414A are located in approximately the same plane perpendicular to the third direction Z.

[0088] The first fixture 432A and the second fixture 434A are preferably disposed in positions close to the narrow portion 414A. For example, the first fixture 432A and the second fixture 434A are preferably provided in positions facing each other across the first space 402A.

[0089] In this embodiment, at least a portion of the first wiring 440A passes through the first space 402A. In this case, the first wiring 440A can be arranged spatially more efficiently than when the first wiring 440A passes through a region different from the first space 402A.

[0090] Furthermore, in this embodiment, at least a portion of the first wiring 440A passes through a portion of the first base 302A that is horizontally shifted from a portion located below the narrow width portion 414A. In this embodiment, a through-hole through which the first wiring 440A passes is provided in the bottom surface of a recess in the first base 302A that defines the second space 304A. The through-hole is located on the negative side of the region directly below the narrow width portion 414A in the first direction X. This makes it difficult for the narrow width portion 414A, which has melted and fallen into the second space 304A, to come into contact with the first wiring 440A.

[0091] The first wiring 440A has one end connected to the second wide portion 416A and the other end connected to the first connector 330A shown in FIG. 3. A portion of the first wiring 440A is drawn downward from the end of the first wiring 440A connected to the second wide portion 416A and passes through the first space 402A and the second space 304A. Another portion of the first wiring 440A passes through a portion of the first base 302A located below the second space 304A and the region between the two rightmost first frames 340A and is drawn into the space below the first frames 340A. Another portion of the first wiring 440A passes through the space between adjacent first frames 340A in a region shifted to the right from the center of the first holder 300A and is drawn from the space below the first frames 340A to the first connector 330A located above the first frames 340A. The routing of the first wiring 440A is not limited to the example according to this embodiment.

[0092] In this embodiment, one end of the first wiring 440A, which is connected to the second wide portion 416A, is fixed to the second wide portion 416A by the second fastener 434A. In this embodiment, the first wiring 440A can be easily attached and detached when the narrow portion 414A melts, compared to when the one end of the first wiring 440A is fixed to the second wide portion 416A by, for example, soldering. A connecting component such as a crimp terminal may be provided at the one end of the first wiring 440A. In this case, the connecting component is fixed by the second fastener 434A, thereby fixing the one end of the first wiring 440A to the second wide portion 416A. However, the method for connecting the one end of the first wiring 440A to the second wide portion 416A is not limited to this example.

[0093] In addition, in this embodiment, the second fixture 434A fixes both the second wide portion 416A and one end of the first wiring 440A connected to the second wide portion 416A to the first base 302A. In this case, the number of parts can be reduced compared to when a fixture for fixing the second wide portion 416A to the first base 302A and a fixture for fixing the one end of the first wiring 440A to the first base 302A are separately provided. In another example different from this embodiment, the fixture for fixing the second wide portion 416A to the first base 302A and the fixture for fixing the one end of the first wiring 440A to the first base 302A may be separately provided.

[0094] The portion of the second wide portion 416A where the second fastener 434A is provided functions as a voltage detection unit that detects the voltage of the terminating positive lead 112T. That is, the terminating positive lead 112T is the voltage detection target of the portion of the second wide portion 416A where the second fastener 434A is provided. The first wiring 440A functions as a voltage detection line electrically connected to the voltage detection unit. In this embodiment, one end of the first wiring 440A fixed by the second fastener 434A is electrically connected to the second wide portion 416A. In this case, compared to when the first wiring 440A is electrically connected to the first wide portion 412A, the influence of the voltage drop in the narrow portion 414A can be suppressed to detect the voltage of the terminating positive lead 112T, and therefore the voltage of the terminating positive lead 112T can be detected more accurately.

[0095] 3 and 6, the second extension 420A is electrically connected to the terminal positive electrode lead 112T. In this embodiment, the right side surface of the second extension 420A and the left side surface of the terminal positive electrode lead 112T are joined to each other by a joining method such as laser welding. The second extension 420A does not necessarily have to be provided. When the second extension 420A is not provided, the terminal positive electrode lead 112T and the first extension 410A can also be electrically connected via an L-shaped bus bar (not shown).

[0096] At least a portion of the second extension 420A is held by at least a portion of the first base 302A. In this embodiment, the upper end of the second extension 420A is held by both side surfaces in the second direction Y of a through hole in the first base 302A through which the upper end of the second extension 420A passes. Furthermore, the lower end of the second extension 420A is held by both side surfaces in the second direction Y of a hole in the first base 302A into which the lower end of the second extension 420A is inserted. This embodiment is preferable because it can suppress the application of a force that rotates the narrow width portion 414A in a direction perpendicular to the vertical direction, compared to when the second extension 420A is not held by the first base 302A. Therefore, it is possible to further suppress breakage of the narrow width portion 414A, compared to when the second extension 420A is not held by the first base 302A.

[0097] Although the embodiments of the present invention have been described above with reference to the drawings, these are merely examples of the present invention, and various other configurations can also be adopted.

[0098] For example, the first fuse device 40A according to the embodiment is electrically connected to the battery cell 100. However, the first fuse device 40A may be electrically connected to an electronic device different from the battery cell 100. The same applies to the second fuse device 40B. Below, examples of reference forms are given. 1. A holder; a voltage detection unit held by the holder; a conductor attached to the carrier, at least a portion of which functions as a fuse; A voltage detection device comprising: 2. The voltage detection device according to 1., wherein both portions of the conductor connected to both ends of the fuse are fixed to the holder. 3. Wiring electrically connected to the conductor; a fixture for fixing at least a portion of the conductor and at least a portion of the wiring to the holder; 3. The voltage detection device according to 1. or 2., further comprising: 4. A voltage detection device described in any one of 1. to 3., further comprising a voltage detection unit electrically connected to the part of the conductor that is electrically connected to the object of voltage detection, out of the two parts connected to both ends of the fuse. 5. The conductor has a plurality of extensions extending in different directions from each other, The voltage detection device according to any one of 1. to 4., wherein at least a portion of at least one of the plurality of extension bodies is held by at least a portion of the holding body. 6. A voltage detection device according to any one of 1. to 5., a battery cell having a lead portion connected to the voltage detection unit; A battery module comprising: [Explanation of symbols]

[0099] 10 Cell stack 20 Containment Unit 30A First Voltage Detector 30B Second voltage detection device 40A First Fuse Device 40B Second fuse device 50 Battery Module 100 battery cells 100G cell group 102 Exterior materials 104 Adhesive material 110 Lead section 112 Positive lead 112T Termination Positive Lead 114 Negative lead 114T Negative terminal lead 210 first cover member 220 second cover member 230 Third cover member 240 Fourth cover member 250 Fifth cover member 260 Sixth cover member 300A 1st holding body 300B 2nd holding body 302A 1st Base 304A 2nd space 310A First voltage detection unit 310B Second voltage detection unit 312A First proximal end 314A 1st tip 316A 1st connection 316aA 1st barrel 318A 1st support shaft 320A First voltage detection wire 320B Second voltage detection line 330A 1st Connector 330B 2nd Connector 340A 1st Frame 340B 2nd frame 342A 1st edge 344A Second edge 346A Third edge 348A Fourth edge 350A notch 400A First Conductor 402A 1st space 410A First extension 412A First wide section 414A Narrow section 416A Second wide section 420A Second extension 432A 1st fixture 434A 2nd fixture 440A 1st Wiring 450A Fastening Hole X 1st direction Y Second direction Z 3rd direction

Claims

1. With the base, a busbar, at least a portion of which functions as a fuse; Equipped with The fuse device, wherein the base and portions of the bus bar located on both sides of the fuse are fixed to each other.

2. The fuse apparatus of claim 1 , wherein the base and the portion of the bus bar are secured together by a fastener.

3. The fuse device of claim 2 , wherein at least a portion of the fastener passes through the base and the bus bar.

4. The fuse device according to any one of claims 1 to 3, wherein the bus bar has a terminal for electrically connecting to an external device.

5. The fuse apparatus of claim 4 , wherein the terminal has a fastening hole.

6. The fuse apparatus of claim 5 , wherein the fastening hole is located higher than the fuse.

7. The fuse device according to any one of claims 1 to 6, wherein a cross-sectional area of the fuse of the bus bar is smaller than a cross-sectional area of the portions of the bus bar located on both sides of the fuse.

8. a partition wall separating the fuse from a battery cell electrically connected to the bus bar; The fuse device according to any one of claims 1 to 7, wherein at least a portion of the fuse is disposed along the partition wall.

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