JP6692965B2 - Battery pack - Google Patents

Description

  The present invention relates to an assembled battery.

  Conventionally, a chargeable / dischargeable battery module including a plurality of battery cells is known. For example, Patent Document 1 discloses a battery module in which a plurality of battery cells are arranged inside a combined upper frame and lower frame.

Patent No. 5154454

However, in the battery module disclosed in Patent Document 1, the outer surface of the battery cell on which the electrode tab is formed is different from the outer surface of the battery cell for positioning the battery cell on the lower frame. In such a case, if the battery cells are positioned on the lower frame and then the electrode tabs of the adjacent battery cells are welded to each other, it may not be possible to secure sufficient accuracy in positioning the electrode tabs.

An object of the present invention made in view of such a viewpoint is to provide an assembled battery that can be accurately positioned when the electrode tabs of adjacent battery cells are welded to each other .

In order to solve the above problems, the assembled battery according to an embodiment of the present invention,
A plurality of stacked battery cells are housed between the first case and the second case,
The battery cell is
Electrode tab,
An exterior member,
The exterior member is
A first outer surface from which the electrode tab protrudes and faces the protruding direction of the electrode tab;
A third outer surface that intersects the first outer surface and faces the stacking direction of the battery cells,
The third outer surface includes two surfaces facing in opposite directions,
The electrode tab of one of the battery cells is laser-welded to the electrode tabs of the other adjacent battery cells outside the first case,
The first case and the second case are divided so as to sandwich the battery cell from the side surface side of the electrode tab,
The first case is
The electrodes of the plurality of battery cells that extend along the protruding direction of the electrode tab from a portion facing a part of the electrode tab to a portion facing an end of the third outer surface, and are stacked. An insulating portion that is disposed between the tabs and insulates the adjacent electrode tabs from each other,
A guide portion having a tapered portion that protrudes from the insulating portion along the stacking direction of the battery cells and has a tapered shape toward the opposite side to the insertion direction of the electrode tab,
In a state where the electrode tab is inserted into the guide portion, a contact portion that contacts the electrode tab and restricts movement of the electrode tab in the insertion direction of the electrode tab,
The guide portions protruding from the adjacent insulating portions are
A portion that projects toward both sides of the electrode tab and guides both sides when accommodating the electrode tab,
On the same side in the projecting direction of the electrode tab, projecting toward each end of the two surfaces of the third outer surface, and guiding the end when accommodating the electrode tab,
Ends of the two surfaces of the third outer surface on the same side in the protruding direction of the electrode tab and a portion that projects toward both surfaces of the electrode tab and guides both surfaces when accommodating the electrode tab. The portions projecting toward and guiding the end when accommodating the electrode tab are separated from each other.

FIG. 1 is a top perspective view showing an appearance of an assembled battery according to a first embodiment of the present invention. It is a disassembled perspective view by the top view which decomposed | disassembled a part of assembled battery shown in FIG. FIG. 3 is an exploded perspective view of each part of the main body of the battery pack shown in FIG. 2. It is a figure which shows the battery cell 10 simple substance of FIG. It is the figure which showed a mode that a battery cell was inserted in the 1st case of FIG. It is a front view of the 1st case of FIG. FIG. 7 is a sectional view taken along the line VII-VII in FIG. 2. It is a schematic diagram which shows the process for assembling the main body of the assembled battery shown in FIG. It is the schematic diagram which showed the 4th process of assembling an insulating sheet and a restraint plate to the main body of the assembled battery shown in FIG. It is a schematic diagram which showed the 5th process of attaching a bus bar to the main body of the assembled battery shown in FIG. It is a schematic diagram which showed the 6th process of attaching a voltage detection part to the main body of the assembled battery shown in FIG. It is a perspective view by an upper surface view which shows the external appearance of the assembled battery which concerns on 2nd Embodiment of this invention. It is a figure which shows the battery cell single body of the assembled battery which concerns on a modification.

  An embodiment will be described below with reference to the accompanying drawings. The front-back, left-right, and up-down directions in the following description are based on the directions of the arrows in the drawings. Hereinafter, as an example, the stacking direction of the plurality of battery cells 10 will be described as the vertical direction, but the stacking direction is not limited thereto. The stacking direction of the plurality of battery cells 10 may match any other direction.

(First embodiment)
FIG. 1 is a top perspective view showing an appearance of an assembled battery 1 according to the first embodiment of the present invention. FIG. 2 is an exploded perspective view from a top view in which a part of the battery pack 1 shown in FIG. 1 is disassembled. FIG. 3 is an exploded perspective view of each part of the main body 1a of the battery pack 1 shown in FIG. The battery pack 1 has a main body 1a, a bus bar 40, an insulating sheet 50, a restraint plate 60, and a voltage detection unit 70 as major components. The main body 1a includes six battery cells 10, a first case 20, and a second case 30.

  As shown in FIG. 3, the six battery cells 10 are vertically stacked. Hereinafter, the six stacked battery cells 10 will be referred to as battery cells 10a, 10b, 10c, 10d, 10e, and 10f from the bottom to the top. When the battery cells are not distinguished, they are collectively referred to as the battery cell 10. Each battery cell 10 has two first outer surfaces 11 that are respectively formed by a front surface and a rear surface that are substantially parallel to the vertical direction. Each battery cell 10 has a pair of electrode tabs 12p and 12n projecting from the two first outer surfaces 11 in opposite directions along a direction substantially perpendicular to the stacking direction, particularly along the front-back direction. Each battery cell 10 is stacked with a pair of electrode tabs 12p and 12n arranged in the front-rear direction.

  The battery cell 10 has two second outer surfaces 13 that intersect the first outer surface 11 and are configured by two lateral side surfaces. The battery cell 10 has two third outer surfaces 14 that intersect the first outer surface 11 and the second outer surface 13. The two third outer surfaces 14 are respectively configured by the upper surface and the lower surface of the battery cell 10, and intersect the axis extending in the stacking direction, that is, the vertical axis.

  The first case 20 and the second case 30 may be made of any material having high rigidity, and are made of, for example, a metal material or a resin material whose surface is provided with an electrically insulating material such as PET resin. ..

  The first case 20 and the second case 30 are each formed in a substantially U shape. The first case 20 and the second case 30 are divided along the protruding direction of the electrode tabs 12p and 12n, that is, the front-back direction. The first case 20 and the second case 30 cover the first outer surface 11 of the battery cell 10 in a state of being engaged with each other, and support the stacked battery cells 10 inside. That is, the stacked battery cells 10 are placed on the bottom surface 20 a of the first case 20 and the bottom surface 30 a of the second case 30. The engaged first case 20 and second case 30 have openings O1 and O2 formed on the bottom surface and the top surface, respectively. The connection surface S between the first case 20 and the second case 30 is substantially orthogonal to the first outer surface 11 of the battery cell 10, and is substantially parallel to the protruding direction of the electrode tabs 12p and 12n, that is, the front-back direction. The connection surface S is also substantially parallel to the vertical direction. Thus, the first case 20 and the second case 30 are engaged or separated in the left-right direction.

  In the first case 20 and the second case 30, the engagement claws E1 are formed on the front and rear sides of one of the upper and lower surfaces, and the engagement holes E2 are formed on the front and rear sides of the other corresponding upper and lower surfaces. They may be engaged with each other. That is, when the first case 20 and the second case 30 are engaged, the engagement claw E1 engages with the engagement hole E2. The assembled battery 1 is not limited to the configuration in which the claw and the hole are engaged with each other. For example, the first case 20 and the second case 30 may be engaged with each other by sandwiching an arbitrary convex portion projecting from each of the upper and lower surfaces thereof with an elastic member such as a clip. Further, the first case 20 and the second case 30 may be engaged with each other by any fastening structure such as screwing. As described above, the battery pack 1 may have any engagement structure as long as the first case 20 and the second case 30 can be reliably engaged with each other. As a result, the assembled battery 1 can realize good assemblability, and as a result, can contribute to improvement of product reliability.

  As shown in FIG. 2, the bus bar 40 has a total plus bus bar 40a and a total minus bus bar 40b. The bus bar 40 is formed of a metal such as aluminum or copper in the shape shown in FIG. The total plus bus bar 40a is connected to the electrode tab 12p of the battery cell 10a. The total minus bus bar 40b is connected to the electrode tab 12n of the battery cell 10f.

  The insulating sheet 50 is formed of an electrically insulating material such as polyethylene (PE: polyethylene) or polypropylene (PP: polypropylene) resin in a substantially flat plate shape. The insulating sheet 50 is arranged so as to abut the upper surface of the battery cell 10f located at the upper end of the stacked battery cells 10. Similarly, the insulating sheet 50 is arranged so as to contact the lower surface of the battery cell 10a located at the lower end of the stacked battery cells 10. The insulating sheet 50 is provided to ensure electrical insulation between the restraint plates 60 fixed to the upper surface and the lower surface of the assembled battery 1 and the battery cells 10 inside the assembled battery 1.

  The restraint plate 60 is preferably made of any material having high rigidity. For example, the restraint plate 60 is preferably made of only a metal material. The present invention is not limited to this, and the constraining plate 60 may be made of a metal material or a resin material having a surface coated with an electrically insulating material such as PET resin. The restraint plate 60 is formed in a substantially flat plate shape.

  The restraint plate 60 is arranged on the upper surface and the lower surface of the battery pack 1 so as to contact the upper surface and the lower surface of the insulating sheet 50, respectively. The restraint plate 60 is fixed to the upper and lower surfaces of the engaged first case 20 and second case 30 by an appropriate method such as screwing. For example, the hole portions 61 penetrating the four corners of the restraint plate 60 are provided at the two screw holes 21 provided at the front and rear end portions of the side surface of the first case 20 and at the front and rear end portions of the side surface of the second case 30. It is screwed in accordance with the two screw holes 31. Thereby, the constraining plate 60 is fixed to the upper and lower surfaces of the engaged first case 20 and second case 30. The restraint plate 60 restrains the battery cells 10 in the first case 20 and the second case 30 while restraining the two third outer surfaces 14 that are respectively constituted by the upper surface and the lower surface of each battery cell 10 and intersect the axis extending in the stacking direction. To be sandwiched between. At the same time, the restraint plate 60 supports the battery cell 10.

  The voltage detection unit 70 includes a terminal plate 71 for detecting the voltage of the battery cell 10 and a wire 72 for transmitting the detected voltage signal. The voltage detection unit 70 is connected to the corresponding electrode tab of the battery cell 10.

  FIG. 4 is a view showing the battery cell 10 alone of FIG. FIG. 4A is a top view of the battery cell 10. FIG. 4B is a side view of the battery cell 10. FIG. 4 shows, as an example, the battery cells 10b arranged as shown in FIG. The other battery cells 10 have the same configuration as the battery cell 10b shown in FIG.

  The battery cell 10 is formed in a substantially flat plate shape in a top view. The exterior member 16 of the battery cell 10 is made of a laminated film. The outermost layer of the exterior member 16 is made of resin to ensure electric insulation. The upper and lower surfaces of the exterior member 16 form the third outer surface 14, respectively. The first outer surface 11 projects one step further outward than the left and right ends at the center. That is, the first outer surface 11 is formed in a convex shape in a top view. An electrode tab 12p or 12n is provided so as to project from a portion of the first outer surface 11 that projects one step outward. The electrode tabs 12p and 12n project substantially parallel to the front-rear direction and have side surfaces 17 along the projecting direction. As shown in FIG. 4, the electrode tabs 12p and 12n are normally formed in a flat plate shape. However, in the process of assembling the battery pack 1 described later, in order to make contact with the electrode tabs 12p or 12n of the other battery cells 10 that are vertically adjacent to each other or the bus bar 40, it is outwardly facing and has a substantially L shape. Are bent symmetrically with respect to each other. For example, the electrode tab 12p linearly projects outward along the front-rear direction and then bends downward. The electrode tab 12n linearly projects outward along the front-rear direction and then bends upward. Hereinafter, as an example, the electrode tab 12p bent downward is described as a positive electrode terminal, and the electrode tab 12n bent upward is described as a negative electrode terminal, but the present invention is not limited to this. The electrode tabs 12p and 12n may be configured such that the roles of the positive electrode and the negative electrode are reversed.

  The battery cell 10 may have an adhesive layer 15 which is provided on the two third outer surfaces 14 and adheres the adjacent battery cells 10 to each other. The adhesive layer 15 may be provided on only one of the upper and lower third outer surfaces 14. The adhesive layer 15 may be composed of an adhesive or an adhesive such as a double-sided tape. For example, the battery cells 10 adjacent to each other may be adhesively fixed by an arbitrary method such as applying an adhesive to the upper surface and the lower surface of each battery cell 10. Similarly, the battery cell 10 and the insulating sheet 50 may be fixed to each other with an adhesive. Further, the insulating sheet 50 and the constraining plate 60 may also be similarly bonded and fixed with an adhesive.

  FIG. 5 is a diagram showing how the battery cell 10 is inserted into the first case 20 of FIG. FIG. 5A shows the overall appearance. FIG. 5B is an enlarged view of a portion surrounded by a broken line in FIG. FIG. 6 is a front view of the first case 20 of FIG. FIG. 7 is a sectional view taken along the line VII-VII in FIG.

On the front wall 22a and the rear wall 22b of the first case 20, guide portions 23 arranged in the up-down direction are extended along the left-right direction. The guide portion 23 is provided on each of the upper and lower surfaces of the first insulating portion 27 described later (see FIG. 7). The guide portion 23 is formed as a convex portion that projects from the surface of the first insulating portion 27 in both up and down directions. The guide portion 23 guides the electrode tabs 12p and 12n toward the side wall 22c of the first case 20 facing the second outer surface 13 when inserting the battery cell 10. The guide portion 23 has a taper portion 24 that tapers toward the opposite side of the insertion direction of the electrode tabs 12p and 12n (see FIG. 6). Tapered portion 24 is provided continuously wider preparative ing parts of the guide portion 23 extending along the left-right direction. For example, the tapered shape of the tapered portion 24 may be linear or gently curved. As a result, the vertical separation width of each of the guide portions 23 gradually decreases toward the side wall 22c. With the configuration of the tapered portion 24 as described above, the battery pack 1 can further improve the insertability of the battery cell 10 into the first case 20.

  Further, on the rear side of the front wall 22a and the rear wall 22b of the first case 20 into which the battery cells 10 are inserted, a narrow accommodating portion 25 continuous with the tapered portion 24 of the guide portion 23 is provided along the left-right direction. It is formed. The accommodating portion 25 is an internal space formed on the back side of the front surface and the rear surface of the first case 20, and accommodates the electrode tabs 12p and 12n when the battery cell 10 is inserted in the first case 20 (FIG. 7). reference).

  As an example, the electrode tabs 12p and 12n first move in the wide entrance portion of the guide portion 23 when the battery cell 10 is inserted into the first case 20. Subsequently, the electrode tabs 12p and 12n contact, for example, the surface of the tapered portion 24 of the guide portion 23 and slide on the surface. In this way, the electrode tabs 12p and 12n are guided by the tapered portion 24 into the narrow accommodating portion 25.

  The first case 20 has a contact portion 26 that contacts the electrode tab 12p or 12n of the battery cell 10 when the battery cell 10 is inserted. More specifically, the contact portion 26 is an inner wall of the first case 20 to which the side surfaces 17 along the protruding direction of the electrode tab 12p or 12n face each other when the battery cell 10 is inserted into the first case 20. 26a is suitable (see FIG. 5). That is, the inner wall 26 a is configured by the end surface on the back side of the housing portion 25 of the first case 20. In this case, when the battery cell 10 is inserted into the first case 20, the side surface 17 of the battery cell 10 contacts the contact portion 26 of the first case 20, that is, the inner wall 26a.

  The contact portion 26 may further contact the second outer surface 13 of the battery cell 10 when inserting the battery cell 10. More specifically, the contact portion 26 may be configured by the side wall 22c that the second outer surface 13 faces when the battery cell 10 is inserted (see FIG. 5). In this case, when the battery cell 10 is inserted into the first case 20, the second outer surface 13 of the battery cell 10 contacts the contact portion 26 of the first case 20, particularly the side wall 22c.

  As described above, the lateral positioning of each battery cell 10 is performed by bringing the corresponding portion into contact with the contact portion 26 of the first case 20 with the electrode tab 12p or 12n as a reference. The contact portion 26 constitutes a part of the housing portion 25 of the first case 20 in which the electrode tab 12p or 12n is housed. When the contact portion 26 contacts the side surface 17 of the electrode tab 12p or 12n, the battery pack 1 accurately positions the electrode tabs 12p and 12n of the adjacent battery cells 10 in the left-right direction when they are welded to each other. Can be done well. The lateral positioning of each battery cell 10 may be performed with reference to at least one side surface 17 of the electrode tabs 12p and 12n.

  On the other hand, the positioning of each battery cell 10 in the front-back direction may be performed, for example, by causing a corresponding portion of the first outer surface 11 to contact the front wall 22a or the rear wall 22b of the first case 20. That is, the portion of the first outer surface 11 on the side wall 22c side and the portion of the front wall 22a or the rear wall 22b of the first case 20 where the housing portion 25 is not formed are brought into contact with each other, so that the battery cell 10 of each The front-rear direction position may be determined.

  The first case 20 has a first insulating portion 27 that is continuously formed over the inner surfaces of the front wall 22a, the rear wall 22b, and the side wall 22c, and that projects substantially horizontally toward the inside. The first insulating portion 27 insulates the adjacent battery cells 10 in a stacked state from each other. In particular, the first insulating portion 27 electrically insulates the electrode tabs 12p and 12n adjacent to each other in the stacking direction of the battery cells 10 from each other. One first insulating portion 27 is provided between each of the six stacked battery cells 10, five in total.

  The second case 30 that engages with the first case 20 has a shape corresponding to that of the first case 20, as shown in FIG. The second case 30 may have the second insulating portion 37, like the first case 20. Like the first insulating portion 27, the second insulating portion 37 may be continuously formed over the inner surfaces of the front wall 32a, the rear wall 32b, and the side wall 32c of the second case 30. Without being limited to this, the second insulating portion 37 may be formed on at least one of the inner surfaces of the front wall 32a, the rear wall 32b, and the side wall 32c. The second case 30 may have a guide portion and a taper portion with the same configuration as the first case 20.

  FIG. 8 is a schematic view showing a process for assembling the main body 1a of the assembled battery 1 shown in FIG. FIGS. 8A to 8C are schematic views respectively showing typical first to third steps for assembling the main body 1a of the assembled battery 1.

  In the first step shown in FIG. 8A, among the six battery cells 10 to be stacked, the battery cell 10 a housed in the lowermost layer is inserted into the first case 20. As an example, the electrode tab 12p of the battery cell 10a is arranged at the front and the electrode tab 12n is arranged at the rear. When the battery cell 10a is inserted into the first case 20, the side surfaces 17 of the electrode tabs 12p and 12n of the battery cell 10a come into contact with the inner wall 26a of the first case 20. Similarly, the second outer surface 13 of the battery cell 10a may contact the side wall 22c of the first case 20.

  In the second step shown in FIG. 8B, the battery cells 10b to 10f are further inserted into the first case 20 one by one from below. At this time, each battery cell 10 is arranged such that the orientations of the electrode tabs 12p and 12n are opposite to the orientations of the adjacent battery cells 10. That is, the electrode tab 12p of the battery cell 10b is arranged rearward, and the electrode tab 12n is arranged frontward. When the same arrangement is repeated, the electrode tab 12p of the battery cell 10f located in the uppermost layer is arranged rearward and the electrode tab 12n is arranged frontward. Further, the battery cells 10b to 10f are positioned by abutting the corresponding portions of the first case 20, similarly to the battery cell 10a.

  In the third step shown in FIG. 8C, the second case 30 is engaged with the first case 20 so as to cover the opposite side of the battery cell 10 inserted in the first case 20. More specifically, the engaging claws E1 provided on the upper surface and the lower surface of the first case 20 and the engaging holes E2 provided on the upper surface and the lower surface of the second case 30 are engaged with each other. Engage.

  FIG. 9 is a schematic diagram showing a fourth step of assembling the insulating sheet 50 and the constraining plate 60 to the main body 1a of the battery pack 1 shown in FIG.

  When the assembly of the main body 1a is completed, the insulating sheet 50 and the restraint plate 60 are assembled to the main body 1a. In particular, the insulating sheet 50 and the restraint plate 60 are attached to the upper and lower surfaces of the main body 1a. More specifically, the two insulating sheets 50 are arranged so as to contact the upper surface of the battery cell 10f and the lower surface of the battery cell 10a, respectively. The two constraining plates 60 are arranged so as to contact the upper surface and the lower surface of the insulating sheets 50 arranged on the upper and lower sides, respectively.

  FIG. 10 is a schematic diagram showing a fifth step of attaching the bus bar 40 to the main body 1a of the battery pack 1 shown in FIG.

  When the above-mentioned fourth step is completed, the bus bar 40 is attached to the front surface of the main body 1a. More specifically, the position of the total plus bus bar 40a on the front surface of the main body 1a is adjusted so that the insertion portion 41a of the total plus bus bar 40a is located immediately below the electrode tab 12p of the battery cell 10a arranged in the lowermost layer. Similarly, the position of the total minus bus bar 40b on the front surface of the main body 1a is adjusted so that the insertion portion 41b of the total minus bus bar 40b is located immediately above the electrode tab 12n of the battery cell 10f arranged in the uppermost layer. After that, the electrode tabs 12p and 12n protruding substantially horizontally are bent in a predetermined direction. For example, the electrode tab 12p is bent downward and the electrode tab 12n is bent upward.

  FIG. 11 is a schematic diagram showing a sixth step of attaching the voltage detection unit 70 to the main body 1a of the battery pack 1 shown in FIG.

  When the above fifth step is completed, the voltage detection unit 70 is attached to the front surface of the main body 1a. More specifically, with the bent electrode tabs 12p and 12n, and the bent electrode tabs 12p or 12n, and the bus bars 40 overlapped, the terminal board 71 is further overlapped from the front. In this state, the constituent parts arranged on the front surface of the main body 1a of the battery pack 1 are welded together by an appropriate method such as laser welding. That is, the electrode tabs, the electrode tabs and the bus bars 40, and the electrode tabs and the terminal plates 71 are welded to each other. The same applies to the respective constituent parts arranged on the rear surface of the main body 1a of the assembled battery 1.

  As described above, the assembly of the assembled battery 1 as shown in FIG. 1 is completed. In this case, on the front surface of the main body 1a, the insertion portion 41a of the total plus bus bar 40a and the electrode tab 12p of the battery cell 10a are electrically connected. Similarly, the electrode tab 12n of the battery cell 10b and the electrode tab 12p of the battery cell 10c are electrically connected. The electrode tab 12n of the battery cell 10d and the electrode tab 12p of the battery cell 10e are electrically connected. Further, the insertion portion 41b of the total minus bus bar 40b and the electrode tab 12n of the battery cell 10f are electrically connected.

  On the other hand, on the rear surface of the main body 1a, the electrode tabs 12n of the battery cells 10a and the electrode tabs 12p of the battery cells 10b are electrically connected. Similarly, the electrode tab 12n of the battery cell 10c and the electrode tab 12p of the battery cell 10d are electrically connected. The electrode tab 12n of the battery cell 10e and the electrode tab 12p of the battery cell 10f are electrically connected.

  As described above, the electrode tabs 12p and 12n of each battery cell 10 are bent upside down to be connected to the electrode tabs of the adjacent battery cells 10 having opposite polarities. Finally, the six battery cells 10 are connected in series with each other.

Assembled battery 1 according to the first embodiment as the following, when welding the electrode tabs 12p and 12n between the battery cells 10 adjacent, can be accurately positioned. That is, since the side surfaces 17 of the electrode tabs 12p and 12n serve as a positioning reference, the electrode tabs 12p and 12n of the adjacent battery cells 10 can be welded in a precisely positioned state. In this way, the assembled battery 1 can improve the positioning accuracy of the electrode tabs 12p and 12n at the time of welding, as compared with the case where the positioning reference and the portion to be welded are arranged on the outer surfaces of the battery cells in different directions.

  In particular, the battery pack 1 receives the entire side surface 17 of the electrode tab 12p or 12n serving as a positioning reference by using the contact portion 26 as the inner wall 26a of the first case 20 to stably arrange the battery cell 10. can do. This further improves the positioning accuracy of the electrode tabs 12p and 12n during welding. As described above, in the battery pack 1, the welding process of the electrode tabs 12p and 12n can be simplified and the welding work can be facilitated. Thereby, the assembled battery 1 can also contribute to the improvement of reliability as a product.

  In the assembled battery 1, the contact portion 26 further contacts the second outer surface 13 of the battery cell 10, whereby the positioning accuracy of the electrode tabs 12p and 12n can be further improved. In particular, the assembled battery 1 can more accurately position the battery cells 10 in the insertion direction, that is, the horizontal direction.

  In particular, in the battery pack 1, the contact portion 26 is configured by the side wall 22c of the first case 20, so that the positioning accuracy of the electrode tabs 12p and 12n can be further improved. That is, in the assembled battery 1, when the battery cell 10 is inserted, the second outer surface 13 can be reliably abutted against the side wall 22c that is a part of the contact portion 26. Particularly, since the side wall 22c abuts over substantially the entire area of the second outer surface 13 along the front-rear direction of the battery cell 10, the battery pack 1 can provide a positioning reference over a wide area. As a result, in the battery pack 1, if the dimensions of the battery cells 10 are the same, the positions of the electrode tabs 12p and 12n can be reliably aligned between the different battery cells 10.

  In the battery pack 1, since only the first case 20 includes the accommodation portion 25 that accommodates the pair of electrode tabs 12p and 12n, the accommodation portion 25 can be concentrated in one case and the production efficiency can be improved. That is, since the battery pack 1 can collectively form the housing portion 25 in the first case 20, the number of manufacturing steps can be reduced, and the productivity can be improved. Further, the assembled battery 1 can be assembled safely by preventing a short circuit during assembly.

  The battery pack 1 can improve resistance to vibration or impact of the battery pack 1 by fixing the battery cells 10 to each other, the battery cells 10 and the insulating sheets 50 to each other, and the insulating sheets 50 and the constraining plates 60 to each other with an adhesive. For example, when the assembled battery 1 is mounted on a vehicle, it is possible to prevent relative displacement between components due to vibration or shock during traveling. In this way, the assembled battery 1 can firmly fix the internal components to each other to prevent damage to the internal components due to vibration or impact.

  Since the battery pack 1 has the guide portion 23, the insertability of the battery cell 10 into the first case 20 can be improved. Further, in the battery pack 1, the insertability can be further improved by providing the guide portions 23 with the tapered portions 24, respectively. That is, the battery pack 1 can prevent the electrode tabs 12p and 12n from coming into contact with the inner surface of the first case 20 and deforming when inserted, and can reliably store the electrode tabs 12p and 12n in the housing portion 25. In particular, the formation of the tapered portion 24 increases the vertical separation width of each of the guide portions 23 toward the inlet side of the insertion, so that the interference between the electrode tabs 12p and 12n and the first case 20 during insertion is avoided. Easier to do. Thus, the battery pack 1 can be assembled safely and reliably without damaging the electrode tabs 12p and 12n.

  By providing the first insulating portion 27 of the first case 20, the battery pack 1 can ensure electrical insulation in the stacking direction of the adjacent battery cells 10. That is, the insulation can be maintained not only in the initial state but also when the battery cell 10 expands due to deterioration over time and the vertical positions of the electrode tabs 12p and 12n change. The assembled battery 1 can also achieve the same effect by the second insulating portion 37 of the second case 30.

  The assembled battery 1 includes the first case 20 and the second case 30 made of a resin material or a metal material having an electrically insulating material applied to the surface thereof, so that parts such as electric parts arranged outside and an assembled battery. It is possible to ensure electrical insulation from the battery cells 10 inside the unit 1.

  The assembled battery 1 can achieve good assemblability by providing an arbitrary engaging structure, particularly a combination of the engaging claw E1 and the engaging hole E2. As a result, the assembled battery 1 can contribute to improving the reliability of the product.

  In the assembled battery 1, the third outer surface 14 substantially perpendicular to the stacking direction of the battery cells 10 is constrained by the constraining plate 60 so that internal gas is generated during use of the assembled battery 1, during charging / discharging, or after deterioration with time. The expansion of the battery cells 10 in the stacking direction can be suppressed. By forming the constraining plate 60 with a metal material, the battery pack 1 can improve its rigidity and effectively suppress the expansion of the battery cell 10. On the other hand, in the battery pack 1, like the first case 20 and the second case 30, the constraining plate 60 is formed of a metal material or a resin material to which an electrically insulating material is applied, so that the electrically insulating property is obtained. It can be further improved. Further, in such a case, since the battery pack 1 can be manufactured at low cost by reducing the weight of the restraint plate 60, it is possible to contribute to the weight reduction and cost reduction of the battery pack 1 itself.

  In the assembled battery 1, the battery cells 10 are firmly restrained from both upper and lower directions by restraining the battery cells 10 from both upper and lower sides by the restraint plates 60. That is, since the battery cell 10 in which the constraining plates 60 having high rigidity are stacked is sandwiched from both the upper and lower directions, the pressure holding property is improved. Therefore, the assembled battery 1 can further suppress expansion of the battery cells 10 in the stacking direction. Similarly, the assembled battery 1 can improve the supportability of the stacked battery cells 10. That is, the assembled battery 1 can regulate the vertical position of each battery cell 10. Further, due to the restraint from the vertical direction, the first case 20 and the second case 30 are less likely to bend even when the stacked battery cells 10 are supported. In other words, the upper and lower restraint plates 60 restrict the bending of the first case 20 and the second case 30.

  The assembled battery 1 can suppress the deterioration of the first case 20 and the second case 30 by providing the openings O1 and O2. For example, if the restraint plate 60 is directly arranged on the upper surface and the lower surface of the first case 20 and the second case 30 without providing the openings O1 and O2, the restraint plate 60 directly pressurizes these cases. The case is deformed and deterioration is accelerated. Therefore, the battery pack 1 can prevent damage to the case due to such deterioration over time.

  The battery pack 1 can ensure electrical insulation between the restraint plate 60 and the internal battery cells 10 by disposing the insulating sheet 50.

  The assembled battery 1 has a symmetrical shape by the electrode tabs 12p and 12n of the battery cell 10 protruding in opposite directions along the front-rear direction, and improves the symmetry of the first case 20. That is, in the assembled battery 1, the first case 20 can be formed with good balance.

(Second embodiment)
FIG. 12 is a top perspective view showing the external appearance of the assembled battery 1 according to the second embodiment of the present invention. As shown in FIG. 12, the assembled battery 1 according to the second embodiment has, in addition to the configuration of the assembled battery 1 according to the first embodiment, an exhaust unit for exhausting gas generated inside the battery cells 10 to the outside. Equipped with 80. Below, the same code | symbol is attached | subjected about the same component as 1st Embodiment. Further, the description will be omitted, and the description will be given mainly by focusing on the discharge unit 80 different from the first embodiment.

  For example, one discharge unit 80 is provided on the side surface of the first case 20. The discharge part 80 has a discharge tube 81 extending outward from the side surface. The discharge unit 80 may be provided on any outer surface of the first case 20 and the second case 30 as long as the internal gas can be efficiently discharged to the outside. The discharge unit 80 is not limited to one, and a plurality of discharge units 80 may be provided.

  Gas is generated inside the battery cell 10 as it ages. When the pressure of the internal gas exceeds a predetermined value, the internal gas is released from the peripheral end of the battery cell 10 to the outside. The discharge part 80 guides the internal gas discharged from the battery cell 10 to the outside of the assembled battery 1 through the discharge tube 81.

  The assembled battery 1 according to the second embodiment as described above has the same effects as the effects described above in the first embodiment. In addition, the assembled battery 1 according to the second embodiment can improve safety by guiding the internal gas to the outside by the discharge part 80. In other words, the battery pack 1 can improve reliability as a product.

  It will be apparent to those skilled in the art that the present invention can be implemented in other predetermined forms than the above-described embodiments without departing from the spirit or the essential characteristics thereof. Therefore, the above description is exemplary and not restrictive. The scope of the invention is defined by the appended claims rather than by the preceding description. All changes, which are within their equivalent scope, are to be included therein.

  In the above description, the electrode tabs 12p and 12n of the battery cell 10 have been described as protruding in opposite directions along the front-rear direction, but the invention is not limited thereto. The electrode tabs 12p and 12n may be formed on the same surface. FIG. 13: is a figure which shows the battery cell 10 simple substance of the assembled battery 1 which concerns on a modification.

  For example, as shown in FIG. 13, the front surface of the battery cell 10 projects one step further outward than the left and right end portions at the center of each of the two halves along the left-right direction. That is, the front first outer surface 11 is formed such that the two convex shapes are continuous in the left-right direction in a top view. Electrode tabs 12p and 12n are provided so as to project forward from two portions of the first outer surface 11 that project outward by one step.

  The first case 20 and the second case 30 may have any configuration capable of accommodating the battery cells 10 as shown in FIG. 13 in a stacked state. Particularly, the six battery cells 10 are stacked such that the electrode tabs 12p and 12n of the adjacent battery cells 10 are staggered in the left-right direction. Therefore, it is preferable that the first case 20 and the second case 30 are configured in a shape that can appropriately accommodate the six battery cells 10 stacked in this way.

  As an example, in at least one of the first case 20 and the second case 30, the accommodating portion 25 that accommodates the pair of electrode tabs 12p and 12n is centrally formed on one outer surface, for example, the front surface. As a result, the battery pack 1 can reduce the number of assembly steps. The assembled battery 1 can contribute to improvement in productivity. Further, since the electrode tabs 12p and 12n of the battery cell 10 are formed only on the front first outer surface 11 and the rear portion of the battery cell 10 is flat, the front-back width of the battery cell 10 is equal to that of the electrode tab 12p or 12n. Just shorter. Along with this, the front-rear width of the case also becomes shorter, and the assembled battery 1 can contribute to downsizing as a whole.

  Although the configuration in which the contact portion 26 is provided only in the first case 20 has been described above, the configuration is not limited to this. For example, the second case 30 may have an abutting portion, and in this case, the abutting portion may be formed by inner walls corresponding to the side surfaces 17 of the electrode tabs 12p and 12n of the battery cell 10. Further, both the first case 20 and the second case 30 may have a contact portion.

  The assembled battery 1 may not have the tapered portion 24 as long as the insertability of the battery cell 10 into the first case 20 and the second case 30 can be ensured.

  The assembled battery 1 is not limited to the configuration in which the guide portion 23 is provided independently. For example, the battery pack 1 may be configured such that the guide portion 23 is not provided and the first insulating portion 27 is also used as the guide portion. In this case, the insertability of the battery cell 10 may be improved by providing the first insulating portion 27 with a tapered shape.

  The number of the battery cells 10 and the numbers of the guide portions 23, the accommodating portions 25, etc. are not limited to the above configuration. The number of battery cells 10 may be any number. The guide portion 23, the housing portion 25, and the like may be formed in an optimum manner according to the number of battery cells 10.

  In the assembled battery 1, the insulating sheet 50 and the restraint plate 60 may be provided only on one end of the first case 20 and the second case 30 in the vertical direction. Thereby, the assembled battery 1 can reduce the number of parts and improve productivity.

1 Battery pack 1a Main body 10, 10a, 10b, 10c, 10d, 10e, 10f Battery cell 11 First outer surface 12p, 12n Electrode tab 13 Second outer surface 14 Third outer surface 15 Adhesive layer 16 Exterior member 17 Side surface 20 First case 20a Bottom surface 21 Screw hole 22a Front wall 22b Rear wall 22c Side wall 23 Guide portion 24 Tapered portion 25 Housing portion 26 Contact portion 26a Inner wall 27 First insulating portion 30 Second case 30a Bottom surface 31 Screw hole 32a Front wall 32b Rear wall 32c Side wall 37 2nd insulating part 40 Bus bar 40a Total plus bus bar 40b Total minus bus bar 41a Insert part 41b Insert part 50 Insulation sheet 60 Restraint plate 61 Hole 70 Voltage detection part 71 Terminal plate 72 Wire 80 Discharge part 81 Discharge tube E1 Engagement claw E2 Engagement holes O1, O2 Opening S Connection surface

Claims (3)

An assembled battery in which a plurality of stacked battery cells are housed between a first case and a second case,
The battery cell is
Electrode tab,
An exterior member,
The exterior member is
A first outer surface from which the electrode tab protrudes and faces the protruding direction of the electrode tab;
A third outer surface that intersects the first outer surface and faces the stacking direction of the battery cells,
The third outer surface includes two surfaces facing in opposite directions,
The electrode tab of one of the battery cells is laser-welded to the electrode tabs of the other adjacent battery cells outside the first case,
The first case and the second case are divided so as to sandwich the battery cell from the side surface side of the electrode tab,
The first case is
The electrodes of the plurality of battery cells that extend along the protruding direction of the electrode tab from a portion facing a part of the electrode tab to a portion facing an end of the third outer surface, and are stacked. An insulating portion that is disposed between the tabs and insulates the adjacent electrode tabs from each other,
A guide portion having a tapered portion that protrudes from the insulating portion along the stacking direction of the battery cells and has a tapered shape toward the opposite side to the insertion direction of the electrode tab,
In a state where the electrode tab is inserted into the guide portion, a contact portion that contacts the electrode tab and restricts movement of the electrode tab in the insertion direction of the electrode tab,
The guide portions protruding from the adjacent insulating portions are
A portion that projects toward both sides of the electrode tab and guides both sides when accommodating the electrode tab,
On the same side in the projecting direction of the electrode tab, projecting toward each end of the two surfaces of the third outer surface, and guiding the end when accommodating the electrode tab,
Ends of the two surfaces of the third outer surface on the same side in the protruding direction of the electrode tab and a portion that projects toward both surfaces of the electrode tab and guides both surfaces when accommodating the electrode tab. The assembled battery in which portions that project toward and guide the ends when accommodating the electrode tabs are separated from each other. The assembled battery according to claim 1, wherein
In the guide part,
Ends of the two surfaces of the third outer surface on the same side in the protruding direction of the electrode tab and a portion that projects toward both surfaces of the electrode tab and guides both surfaces when accommodating the electrode tab. An assembled battery in which a space is formed between the portions projecting toward and guiding the end when accommodating the electrode tab. The assembled battery according to claim 1 or 2, wherein
The battery assembly, wherein the insulating portion extends from a portion facing the end portion of the third outer surface in a direction opposite to a protruding direction of the electrode tab.