JP6532568B1 - Assembled battery - Google Patents

Abstract

[Problem] To provide an assembled battery whose productivity can be improved. An assembled battery 1 includes a plurality of battery cells 10 stacked along a predetermined direction, cell cases 20, 30 for accommodating the battery cells 10, and restraint plates attached to the cell cases 20, 30. And 60. The cell cases 20 and 30 have openings 22 and 32 at both ends in a predetermined direction. The restraint plate 60 pressurizes the battery cell 10 through the openings 22 and 32 from the side of one end in a predetermined direction. [Selected figure] Figure 10

Description

  The present invention relates to a battery pack.

  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 disposed inside a combined upper frame and lower frame.

Patent No. 5154454

  In the battery module disclosed in Patent Document 1, the battery cell is installed on the frame in a state of being surrounded by the cell cover. Productivity may be reduced by the process of enclosing a battery cell with a cell cover.

  An object of the present invention made in view of such a point is to provide a battery pack in which productivity can be enhanced.

In order to solve the above problems, a battery assembly according to an embodiment of the present invention is provided with a plurality of battery cells stacked along a predetermined direction, a cell case for housing the battery cells, and the cell case And a case for housing the cell case . The cell case has an opening at each end of the predetermined direction. The restraint plate presses the battery cell from the side of one end in the predetermined direction through the opening. The case has a bottom surface. The bottom surface of the case is pressing the battery cell through the opening from the side opposite to the side where the restraint plate presses the battery cell.

  According to the battery assembly of one embodiment of the present invention, productivity can be enhanced.

It is an exploded perspective view showing an example of composition of a group battery concerning one embodiment. BRIEF DESCRIPTION OF THE DRAWINGS It is an external appearance perspective view which shows the structural example of the assembled battery which concerns on one Embodiment. It is an (A) top view (B) side view showing an example of composition of a battery cell. It is an exploded perspective view showing an example of composition of a battery module. It is a perspective view which shows an example of the assembly process of a battery module. It is a disassembled perspective view which shows the structural example of an accessory module. It is a perspective view which shows the example of an assembly of a battery module and an accessory module. It is an exploded perspective view showing an example of composition of an upper case. It is a perspective view which shows the structural example by which the battery module is accommodated in the lower case. It is AA sectional drawing of FIG. It is an enlarged view of the broken-line enclosure part of FIG. It is sectional drawing which shows the example of the shape of the convex part of a lower case (A) offset shape (B) camber shape (C) rib shape. It is sectional drawing which shows the example of the shape of the convex part of a restraint board (A) offset shape (B) camber shape (C) rib shape. It is a top view which shows the other structural example of a battery cell.

  Hereinafter, one embodiment will be described with reference to the drawings. The front-back, left-right, and top-bottom directions in the following description are based on the directions of arrows in the drawings. In the present embodiment, as an example, the predetermined direction in which the plurality of battery cells 10 (see FIG. 4 and the like) are stacked is described as the vertical direction. The predetermined direction in which the plurality of battery cells 10 are stacked is not limited to the vertical direction, and may be any other direction.

  In the present embodiment, the battery assembly 1 (see FIG. 1 and the like) may be mounted and used in a vehicle equipped with an internal combustion engine or a hybrid vehicle capable of traveling with both the internal combustion engine and a motor. . The battery assembly 1 may be mounted, for example, under a seat of a vehicle. The battery assembly 1 may be mounted, for example, in a center console of a vehicle. The battery assembly 1 is not limited to vehicles, and may be used in other applications.

  As shown in FIG. 1, the assembled battery 1 includes a battery module 100, an accessory module 200, a lower case 300, and an upper case 400. The lower case 300 and the upper case 400 form a space inside the battery assembly 1 by being joined by, for example, a fastening structure such as screwing or a fitting structure such as a claw or a clip. The lower case 300 and the upper case 400 are simply referred to collectively as a case. Battery module 100 and accessory module 200 are located in the space formed by lower case 300 and upper case 400. The battery module 100 is located on the lower case 300 side. Accessory module 200 is located on the side of upper case 400. That is, accessory module 200 is located on the upper side with respect to battery module 100. The lower case 300 and the upper case 400 are made of, for example, a metal material, but may be made of a resin material.

  The battery module 100 includes a restraint plate 60 located above the battery cells 10 stacked vertically. The restraint plate 60 has a convex portion 62 projecting downward toward the battery cell 10. The lower case 300 has a bottom surface 310 located below. The bottom surface 310 has a convex portion 312 projecting upward toward the battery cell 10.

  As shown in FIG. 2, the assembled battery 1 includes, in the upper case 400, a plus output terminal 410, a minus output terminal 420, a connector 430, and a gas discharge part 440. The positive output terminal 410 and the negative output terminal 420 are electrically connected to the electrode tabs 12 (see FIG. 3) of the battery cells 10 included in the battery module 100. Connector 430 is electrically connected to relay 220 (see FIG. 6) and the like included in accessory module 200. The gas discharge unit 440 discharges the gas generated from the battery cell 10 inside the case to the outside of the assembled battery 1.

  As shown in FIGS. 3 (A) and 3 (B), battery cell 10 includes exterior member 16 that holds the electrolyte solution and cell electrodes of battery cell 10, and the front and rear of battery cell 10, respectively. And a pair of negative electrode tabs 12 n and positive electrode tabs 12 p located on the The shape of the battery cell 10 may be flat as a whole. The portion where the electrolytic solution, the cell electrode and the like are held inside by the exterior member 16 is also referred to as a holding portion 18. The portion sealed so as to prevent the leakage of the contents such as the electrolytic solution by bonding, pressure bonding or welding of the exterior member 16 is also referred to as a sealing portion 19. The thickness in the vertical direction of the sealing portion 19 is smaller than the thickness in the vertical direction of the holding portion 18.

  The exterior member 16 may include a laminate film. The outermost layer of the exterior member 16 may include a resin material for securing electrical insulation. In other words, the battery cell 10 may have an insulating member on its surface. The exterior member 16 may include an insulating layer.

  Battery cell 10 has a first outer surface 11 on each of front and rear sides. Battery cell 10 has a second outer surface 13 on the left and right sides, respectively. The first outer surface 11 and the second outer surface 13 may be configured as an end of the exterior member 16. The battery cell 10 has a third outer surface 14 on each of the upper and lower sides of the holding portion 18. The third outer surface 14 may be configured as the outermost layer of the exterior member 16. The extended surfaces of the first outer surface 11, the second outer surface 13, and the third outer surface 14 intersect with each other.

  The negative electrode tab 12 n and the positive electrode tab 12 p are collectively referred to as an electrode tab 12. The negative electrode tab 12 n and the positive electrode tab 12 p may respectively project from the front surface 11 and the rear surface 11. The negative electrode tab 12 n and the positive electrode tab 12 p may be interchanged. The negative electrode tab 12 n and the positive electrode tab 12 p may project in opposite directions. The negative electrode tab 12 n and the positive electrode tab 12 p may protrude in the same direction. In the present embodiment, the battery cell 10 is vertically stacked in a state in which the pair of positive electrode tabs 12p and the negative electrode tabs 12n are disposed along the front-rear direction.

  The electrode tab 12 may project from the center of the first outer surface 11. The electrode tabs 12 may project substantially in parallel in the front-rear direction. The electrode tabs 12 may have tab side surfaces 17 along the projecting direction. The electrode tab 12 may be flat.

  As shown in FIG. 4, the battery module 100 includes battery cells 10 stacked in the vertical direction. The direction in which the battery cells 10 are stacked is also referred to as a predetermined direction. The number of battery cells 10 is not limited to six, and may be five or less, or seven or more. The stacked battery cells 10 may be adhered by an adhesive layer 15 located between the battery cells 10. The battery module 100 may include a heat sink 70 between the stacked battery cells 10. The heat sink 70 may be bonded to the battery cell 10 by the adhesive layer 15.

  The adhesive layer 15 may be provided on the third outer surface 14 of the battery cell 10. The adhesive layer 15 may be provided only on one of the upper and lower two third outer surfaces 14 of the battery cell 10. The adhesive layer 15 may contain an adhesive or an adhesive such as double-sided tape or hot melt. The adhesive layer 15 may be formed by, for example, a method of applying an adhesive to the third outer surface 14 of each battery cell 10, or various other methods. The number of adhesive layers 15 positioned between the components is not limited to two as illustrated in FIG. 4 and may be one or three or more. The shape of the adhesive layer 15 is not limited to the rectangle illustrated in FIG. 4 and may be other various shapes.

  The battery module 100 further includes a first cell case 20 and a second cell case 30. The configuration in which the first cell case 20 and the second cell case 30 are combined is simply referred to as a cell case. The first cell case 20 and the second cell case 30 are respectively located on the left side and the right side of the stacked battery cells 10. The first cell case 20 and the second cell case 30 accommodate the stacked battery cells 10 inside in a state of being engaged with each other. Each of the first cell case 20 and the second cell case 30 may have partition plates 23 and 33 projecting inward from side surfaces. The partition plates 23 and 33 are positioned between the sealing portions 19 of the battery cells 10 in a state in which the first cell case 20 and the second cell case 30 are engaged.

  The shape of the first cell case 20 is a substantially rectangular frame when viewed from above, and the side on the right side is open. In other words, the shape of the first cell case 20 is a U-shape in which the right side is open. The shape of the second cell case 30 is a substantially rectangular frame when viewed from above, and the side on the left side is open. In other words, the shape of the second cell case 30 is a U-shape in which the left side is open. The first cell case 20 and the second cell case 30 engage with each other on the open side, so that they have a rectangular frame shape as viewed from above. The shape of the configuration in which the first cell case 20 and the second cell case 30 are engaged can be said to be in a U-shape when viewed from above. The cell case accommodates the battery cells 10 stacked in a frame-like configuration. The portions corresponding to the inside of the frame when viewed from above are referred to as the opening 22 and the opening 32 in the first cell case 20 and the second cell case 30, respectively. The first cell case 20 has an opening 22 at each end in a predetermined direction in which the battery cells 10 are stacked. The second cell case 30 has openings 32 at both ends in the predetermined direction in which the battery cells 10 are stacked.

  The first cell case 20 and the second cell case 30 may be engaged with each other, for example, by an engagement claw provided on one side and an engagement hole provided on the other side. The first cell case 20 and the second cell case 30 each have, for example, an engagement portion projecting from an arbitrary surface, and the engagement portion projecting is engaged by being held by an elastic member such as a clip. You may The first cell case 20 and the second cell case 30 may be engaged by various fastening structures such as screwing, for example. The first cell case 20 and the second cell case 30 are not limited to these examples, and may be engaged by various methods. By doing so, assembly of the battery assembly 1 can be facilitated. As a result, product reliability may be improved.

  The first cell case 20 and the second cell case 30 may include a material having relatively high rigidity. The first cell case 20 and the second cell case 30 may be made of, for example, a metal material or a resin material or the like to which an electrically insulating material such as PET (Polyethylene Terephthalate) resin is applied on the surface.

  The second cell case 30 has slits 34 in each of the front and rear directions. In the state in which the battery cell 10 is accommodated in the cell case, the electrode tab 12 of the battery cell 10 penetrates the slit 34 and protrudes to the outside of the cell case. The number of slits 34 corresponds to the number of battery cells 10.

  The battery module 100 further includes an inter-tab bus bar 40, a total plus bus bar 41, and a total minus bus bar 42 that electrically connect the electrode tabs 12 projecting outward from the cell case. The inter-tab bus bar 40, the total plus bus bar 41 and the total minus bus bar 42 are simply referred to as a bus bar. The bus bar may be configured to include a metal such as aluminum or copper.

  The battery cells 10 are stacked so that the positive electrode tab 12 p and the negative electrode tab 12 n are alternately interchanged. That is, when the positive electrode tab 12p and the negative electrode tab 12n of one battery cell 10 face forward and backward, respectively, the positive electrode tab 12p and the negative electrode tab 12n of the battery cell 10 stacked next to the battery cell 10 respectively , Facing backward and forward.

  The inter-tab bus bar 40 electrically connects the positive electrode tab 12 p of one battery cell 10 and the negative electrode tab 12 n of the battery cell 10 stacked next to the battery cell 10. By doing this, the stacked battery cells 10 are electrically connected in series. When the battery cells 10 are connected in series, the positive electrode tabs 12 p of the battery cells 10 located at the upper end or the lower end are not connected to any of the battery cells 10. In the present embodiment, it is assumed that the positive electrode tab 12 p of the battery cell 10 located at the upper end is not connected to any of the battery cells 10. The total plus bus bar 41 is connected to the positive electrode tab 12 p of the battery cell 10 located at the upper end. Further, in this case, the negative electrode tab 12 n of the battery cell 10 located at the lower end is not connected to any of the battery cells 10. The total minus bus bar 42 is connected to the negative electrode tab 12 n of the battery cell 10 located at the lower end. By doing this, a potential difference generated between the total plus bus bar 41 and the total minus bus bar 42 is output as the total voltage of the battery cells 10 electrically connected in series.

  The battery assembly 1 may further include a voltage detection unit. The voltage detection unit may be electrically connected to the electrode tab 12 via the bus bar to detect the terminal voltage of each battery cell 10.

  Battery module 100 further includes a restraint plate 60 that restrains battery cells 10 stacked in the vertical direction from above. The restraint plate 60 is fastened by the restraint plate fastening member 64 to the fastening portion 66 provided in the first cell case 20 and the second cell case 30. The broken line in FIG. 4 illustrates an example of the correspondence between the restraint plate fastening member 64 and the fastening portion 66.

  The restraint plate 60 may be configured to include a material having relatively high rigidity. The restraint plate 60 may be made of, for example, only a metal material. The material of the restraint plate 60 is not limited to this, and may be a resin material, or may be a metal material on the surface of which an electrically insulating material such as PET resin is applied. The shape of the restraint plate 60 may be substantially flat. The restraint plate 60 has a convex portion 62. The convex portion 62 of the restraint plate 60 pressurizes the upper surface of the battery cell 10 through the openings 22 and 32 of the cell case. By doing so, the stacked battery cells 10 are restrained, and the battery module 100 can be easily handled. Further, when the restraint plate 60 pressurizes the battery cell 10 through the openings 22 and 32 of the cell case, a force for pressing the battery cell 10 is less likely to be applied to the cell case. As a result, the cell case is less likely to deteriorate or be damaged.

  The battery module 100 may include an insulating sheet 50 between the battery cells 10 stacked in the vertical direction and the restraint plate 60. That is, the restraint plate 60 may be stacked on the battery cell 10 via the insulating sheet 50. The insulating sheet 50 may be adhered to the battery cell 10 by the adhesive layer 15. The insulating sheet 50 may be in contact with the top surface of the battery cell 10 located at the upper end of the stacked battery cells 10. The insulating sheet 50 may be in contact with the lower surface of the battery cell 10 located at the lower end of the stacked battery cells 10. The insulating sheet 50 may include an electrically insulating material such as polyethylene (PE) or polypropylene (PP) resin. The shape of the insulating sheet 50 may be substantially flat, but is not limited thereto. The insulating sheet 50 may be bonded to the restraint plate 60 by the adhesive layer 15. By providing the insulating sheet 50, the electrical insulation between the upper surface of the battery cell 10 and the restraint plate 60 can be improved. The restraint plate 60 may be bonded to the battery cell 10 by the adhesive layer 15 without the insulating sheet 50. When the restraint plate 60 is bonded to the battery cell 10 without the insulating sheet 50, the exterior member 16 of the battery cell 10 may include a layer of the insulating member in the surface layer or the like. The layer of the insulating sheet 50 or the insulating member located between the restraint plate 60 and the battery cell 10 is also referred to as a first insulating layer. By providing the first insulating layer between the restraint plate 60 and the battery cell 10 in the battery module 100, the electrical insulation between the restraint plate 60 and the battery cell 10 can be improved.

  The first cell case 20 may have a side opening 25 on the left side. The second cell case 30 may have a side opening 35 on the right side. When the battery module 100 includes the heat dissipation plate 70, the portions protruding in the left and right direction from the heat dissipation plate 70 may protrude to the outside of the cell case through the side openings 25 and 35.

  The battery module 100 may be assembled along the procedure illustrated in FIGS. 5 (A) to 5 (H).

  In the process shown in FIG. 5A, a jig 90 is used to assemble the battery module 100. The jig 90 may be configured such that the battery cell 10 or the heat sink 70 or the like placed thereon is aligned.

  In the process shown in FIG. 5B, the battery cell 10 is placed on the jig 90. The jig 90 may have an inner surface corresponding to the shapes of the first outer surface 11 and the second outer surface 13 of the battery cell 10 so that the battery cell 10 is placed in the aligned state. The jig 90 may have a shape corresponding to the electrode tab 12 protruding from the center of the first outer surface 11 of the battery cell 10. An adhesive layer 15 may be provided on the upper surface or the lower surface of the battery cell 10.

  In the process shown in FIG. 5C, the heat sink 70 is placed on the jig 90. The jig 90 may have a boss 92 and a step so that the heat sink 70 and the like can be positioned and mounted. The heat sink 70 may have a protrusion and a hole 72 at an end, which is used when the battery module 100 is fastened to the lower case 300. The heat dissipating plate 70 may be aligned by the protrusion coming into contact with the step of the jig 90 and the hole 72 fitting into the boss 92 of the jig 90.

  In the process shown in FIG. 5D, the insulating sheet 50 may be further placed on the top surface of the stacked battery cells 10. An adhesive layer 15 may be provided on the top surface of the insulating sheet 50.

  In the process shown in FIG. 5E, the second cell case 30 is inserted into the configuration in which at least the battery cells 10 are stacked. At that time, the partition plate 33 of the second cell case 30 is inserted between the sealing portions 19 of the stacked battery cells 10. The configuration in which the battery cells 10 are stacked can be aligned even in a state in which the battery cells 10 or the battery cells 10 and the other components are bonded by the adhesive layer 15 and thus taken out of the jig 90. It is possible to maintain the state of being

  In the process illustrated in FIG. 5F, the first cell case 20 is inserted from the opposite side of the second cell case 30 to the configuration in which the battery cells 10 are stacked. At that time, the partition plate 23 of the first cell case 20 is inserted between the sealing portions 19 of the stacked battery cells 10. The electrode tab 12 of the battery cell 10 protrudes from the slit 34 of the second cell case 30 to the outside.

  In the process shown in FIG. 5G, the inter-tab bus bar 40, the total plus bus bar 41, and the total minus bus bar 42 are electrically connected to the electrode tabs 12. The bus bar and the electrode tab 12 may be electrically connected, for example, by welding or welding. When the positive electrode tabs 12p and the negative electrode tabs 12n of the adjacent battery cells 10 are welded to the inter-tab bus bar 40, the battery cells 10 can be welded with high accuracy by maintaining the aligned state.

  Furthermore, the restraint plate 60 is attached from the top to the configuration in which the configuration in which the battery cells 10 are stacked is accommodated in the cell case. The convex portion 62 of the restraint plate 60 abuts on the top surface of the configuration in which the battery cells 10 are stacked through the openings 22 and 32 of the cell case. The restraint plate 60 may be bonded by the adhesive layer 15 to the configuration in which the battery cells 10 are stacked.

  In the step shown in FIG. 5H, the restraint plate 60 may be fastened to the cell case by the restraint plate fastening member 64. The assembly of the battery module 100 is completed by fastening the restraint plate 60 to the cell case.

  When the battery module 100 is assembled along the process illustrated in FIGS. 5A to 5H, the accuracy of positioning of the electrode tabs 12 of the battery cells 10 stacked adjacent to each other can be improved. As a result, the electrode tabs 12 and the bus bars can be easily welded with high accuracy, and the reliability of the assembled battery 1 can be improved.

  Durability when battery module 100 is subjected to vibration, impact, or the like by bonding the laminated portions such as battery cell 10, heat sink 70, insulating sheet 50, or restraint plate 60 with adhesive layer 15. Can be improved. For example, when the battery assembly 1 including the battery module 100 is mounted on a vehicle, relative displacement of each part of the battery module 100 can be reduced due to vibration or impact during traveling of the vehicle. By bonding each part of the battery module 100, each part is less likely to be damaged even when it receives vibration or impact.

  The first cell case 20 and the second cell case 30 respectively have the partition plates 23 and 33 positioned between the sealing portions 19 of the battery cells 10, whereby the battery cells 10 are easily insulated from each other. For example, even when the battery cell 10 is deteriorated and deformed with time, the battery cells 10 stacked adjacent to each other are unlikely to be in contact with each other.

  When the cell case is made of a metal material or resin material or the like whose surface is provided with an electrically insulating material, the electric parts and the like located inside the assembled battery 1 and the battery cell 10 electrically connect each other. It can be insulated.

  In addition, even when the lower case 300 and the upper case 400 of the battery assembly 1 are made of metal, it is possible to ensure insulation between the battery cell 10 and an electrical component or the like located outside the battery assembly 1. If lower case 300 and upper case 400 are made of a resin material, even if the cell case is made of a metal material, similarly, battery cell 10 and an electrical component etc. located outside battery assembly 1. Insulation can be secured.

  As shown in FIG. 6, the accessory module 200 includes an accessory pedestal 210, a relay 220, a current sensor 230, a fuse 240, and a substrate 260. Current sensor 230 has a fastening hole 231 at its terminal, and is fastened to fastening part 212 of accessory pedestal 210 by fastening member 252. The fastening hole 231 at one end of the current sensor 230 is fastened together with the fastening hole 251 of the copper bus bar 250 electrically connected to the relay 220. Relay 220 has a fastening hole 221 at its terminal, and is fastened to fastening part 212 of accessory pedestal 210 by fastening member 252. The fastening hole 221 at one end of the relay 220 is co-fastened with the fastening hole 251 of the copper bus bar 250 electrically connected to the current sensor 230. The fastening hole 221 at the other end of the relay 220 is fastened together with the fastening hole 251 of the copper bus bar 250 electrically connected to the fuse 240. The fuse 240 has a fastening hole 241 in its terminal, and is fastened to the fastening portion 212 of the accessory pedestal 210 by the fastening member 252. The fastening hole 241 at one end of the fuse 240 is co-fastened with the fastening hole 251 of the copper bus bar 250 electrically connected to the relay 220. The substrate 260 has, for example, fastening holes 261 at four corners, and is fastened to the fastening portion 214 of the accessory pedestal 210 by the fastening member 262. Auxiliary machine pedestal 210 has a fastening hole 216. When accessory module 200 is accommodated in lower case 300 together with battery module 100, module fastening member 270 (see FIG. 7) penetrates through fastening hole 216, whereby fastening portion 340 of lower case 300 (FIG. 1). (See).

  As shown in FIG. 7, the accessory pedestal 210 of the accessory module 200 is fastened to the first cell case 20 and the second cell case 30 by a module fastening member 270. The module fastening member 270 may fasten the accessory module 200 and the battery module 100 together to the fastening portion 340 (see FIG. 1) of the lower case 300. Current sensor 230 is electrically connected to copper bus bar 250 electrically connected to total plus bus bar 41 at a terminal different from the side electrically connected to relay 220.

  The battery assembly 1 further includes a plus output terminal 410 and a minus output terminal 420. The fuse 240 is electrically connected to the positive output terminal bus bar 412 electrically connected to the positive output terminal 410 at a terminal different from the side electrically connected to the relay 220. That is, the plus output terminal 410 is electrically connected to the total plus bus bar 41 via the fuse 240, the relay 220, and the current sensor 230 connected in series. The minus output terminal 420 is electrically connected to the total minus bus bar 42 via the minus output terminal bus bar 422. The positive output terminal 410 may be fastened to the fastening portion 330 (see FIG. 1) of the lower case 300 by screwing in the fastening hole 414 or the like. The negative output terminal 420 may be fastened to the lower case 300 by screwing in the fastening hole 424 or the like.

  The battery assembly 1 may further include a bus bar cover 80 covering the inter-tab bus bar 40, the total plus bus bar 41, and the total minus bus bar 42. By covering the bus bar with the bus bar cover 80, the electrical insulation between the bus bar and the lower case 300 is secured even when the assembled battery 1 receives an impact such as a collision, and is deformed or damaged. Can be further enhanced.

  The relay 220 functions as a switching element which connects or disconnects the battery cell 10 and the positive output terminal 410.

  Current sensor 230 detects the magnitude of the current flowing from battery cell 10 to positive output terminal 410. The current sensor 230 may output the magnitude of the detected current to the substrate 260.

  The fuse 240 may include a fuse body, a housing made of insulating resin for housing and holding the fuse body, and a cover made of insulating resin covering the housing. The fuse 240 is melted when an overcurrent flows.

  The substrate 260 may include a BMS (Battery Management System). BMS is also referred to as a battery controller. The BMS may be configured to include at least one processor. The BMS may be communicably connected to the current sensor 230 to obtain a detection result of the current from the current sensor 230. The BMS may be communicably connected to the relay 220 and may output information to control the opening and closing of the relay 220. The BMS may be electrically connected to the inter-tab bus bar 40 and detect the potential of the inter-tab bus bar 40. The BMS may be communicably connected to a sensor that detects the potential of the inter-tab bus bar 40, and may acquire the detection result of the potential of the inter-tab bus bar 40. The BMS may output information regarding the battery cell 10 to the outside through the connector 430 (see FIG. 8).

  As shown in FIG. 8, the upper case 400 includes a connector 430 and a gas outlet 440. Connector 430 is communicably connected to substrate 260 of accessory module 200. The connector 430 may be connectable to an external circuit such as an ECU (Electric Control Unit) of a vehicle on which the battery assembly 1 is mounted, for example.

  Upper case 400 has a fastening portion 450 which is fastened with fastening portion 320 (see FIG. 9) of lower case 300. The fastening portion 320 of the lower case 300 and the fastening portion 450 of the upper case 400 may be fastened by screwing or the like, or may be fastened by an elastic member such as a clip. The case formed by fastening the upper case 400 and the lower case 300 can protect the battery module 100 by surrounding the battery module 100.

  The battery cell 10 may deteriorate over time by repeating charging and discharging. As the battery cell 10 degrades with time, a gas resulting from decomposition or volatilization of the electrolytic solution may be generated inside the battery cell 10. When the pressure of the gas inside the battery cell 10 exceeds a predetermined value, the gas may be released from a part of the sealing portion 19 of the battery cell 10 to the outside. The gas released from the inside of the battery cell 10 can be accumulated in the space inside the assembled battery 1 surrounded by the lower case 300 and the upper case 400. The gas accumulated in the internal space of the assembled battery 1 may be discharged to the outside of the assembled battery 1 through the gas discharge part 440 of the upper case 400. Although the gas discharge part 440 is provided on the upper surface of the upper case 400, the present invention is not limited thereto. The gas discharge part 440 may be provided on the side surface of the upper case 400. May be provided.

  The gas discharge unit 440 has a gas cover 442 and a breather 444. The gas cover 442 can protect the breather 444 from external impact and the like by covering the breather 444. The breather 444 has an internal pressure control film that is both breathable and waterproof and dustproof in the gas discharge path. The gas discharger 440 having the breather 444 discharges the gas accumulated in the internal space of the assembled battery 1 to the outside of the assembled battery 1 and, from the outside of the assembled battery 1, water, dust, etc. It becomes difficult to enter 1 inside. As a result, the reliability of the battery pack 1 can be improved.

  As shown in FIG. 9, the battery module 100 is fastened to the fastening portion 340 (see FIG. 1) of the lower case 300 in a state of being accommodated in the lower case 300. When accessory module 200 is mounted on the upper portion of battery module 100, accessory pedestal 210 and the cell case are collectively fastened to fastening portion 340 of lower case 300 by module fastening member 270 (see FIG. 7). .

  As shown in FIGS. 10 and 11, the lower case 300 has a bottom surface 310 on the lower side. In the state where battery module 100 is housed in lower case 300, stacked battery cells 10 are pressurized from bottom surface 310 located below and restraint plate 60 located above. In other words, the bottom surface 310 of the lower case 300 presses the battery cell 10 from the side opposite to the side where the restraint plate 60 presses the battery cell 10. It can be said that the stacked battery cells 10 are held between the bottom surface 310 and the restraint plate 60. The stacked battery cells 10 can be stably accommodated in the lower case 300 by being held. Since the bottom surface 310 of the lower case 300 has a function of pressing the battery cell 10 from the lower side, a member only for pressing the battery cell 10 from the lower side may be omitted. As a result, the assembled battery 1 can be reduced in size and weight and cost, and the reliability of the holding structure of the battery cell 10 can be improved.

  The bottom surface 310 may abut on the lower surface of the battery cell 10 via the insulating sheet 50. The insulating sheet 50 may be adhered to the bottom surface 310 by the adhesive layer 15. By providing the insulating sheet 50, the electrical insulation between the lower surface of the battery cell 10 and the bottom surface 310 of the lower case 300 can be improved. The bottom surface 310 may be bonded to the battery cell 10 by the adhesive layer 15 without the insulating sheet 50 interposed therebetween. When the bottom surface 310 is bonded to the battery cell 10 without the insulating sheet 50, the exterior member 16 of the battery cell 10 may include the layer of the insulating member in the surface layer or the like. The layer of the insulating sheet 50 or the insulating member located between the bottom surface 310 and the battery cell 10 is also referred to as a second insulating layer. By providing the second insulating layer between the bottom surface 310 and the battery cell 10 in the battery module 100, the electrical insulation between the battery cell 10 and the lower case 300 can be improved.

  The bottom surface 310 has a convex portion 312 projecting upward. The convex portion 312 can contact a predetermined range including the center of the lower surface of the battery cell 10 through the openings 22 and 32 of the cell case. The convex portion 62 of the restraint plate 60 located above the battery module 100 can contact a predetermined range including the center of the upper surface of the battery cell 10 through the openings 22 and 32 of the cell case. The convex portion 62 may abut on the upper surface of the battery cell 10 through another configuration such as the insulating sheet 50 or the like. In the state in which the battery module 100 is accommodated in the lower case 300, the stacked battery cells 10 are sandwiched between the convex portion 312 located below and the convex portion 62 located above. The stacked battery cells 10 are strongly restrained by being held from both upper and lower sides. The stacked battery cells 10 are pressurized by the convex portion 62 and the convex portion 312 in a predetermined range including the center of each of the upper and lower surfaces. The battery cell 10 can be pressurized with a larger force at a central portion of the upper and lower surfaces of the holding portion 18 than the peripheral portion near the sealing portion 19.

  The battery cell 10 may deteriorate over time by repeating charging and discharging. As the battery cell 10 degrades with time, a gas resulting from decomposition or volatilization of the electrolytic solution may be generated inside the battery cell 10. The gas generated inside the battery cell 10 can expand the battery cell 10. The stacked battery cells 10 are less likely to expand in the direction in which the battery cells 10 are stacked by being pressurized from the upper and lower surfaces by the convex portions 62 of the restraint plate 60 and the convex portions 312 of the bottom surface 310.

  As shown in FIG. 12, the cross-sectional shape of the convex portion 312 of the bottom surface 310 of the lower case 300 may be various shapes. The cross-sectional shape of the convex portion 312 is not limited to the shape illustrated in FIG. 12 and may be other various shapes. The cross-sectional shape of the convex portion 312 may be an offset shape in which a part of the surface protrudes uniformly upward, as illustrated in FIG. 12A. The convex portion 312 can press the entire lower surface of the battery cell 10 because a part of the surface protrudes uniformly. Further, the shape of the convex portion 312 can be appropriately determined so as to control the force applied to the battery cell 10.

  The cross-sectional shape of the convex portion 312 may be a camber shape in which the amount of upward protrusion gradually increases from the periphery to the center, as illustrated in FIG. 12B. In the camber shape, the central protrusion is the largest. When the amount of central protrusion is larger than the amount of peripheral protrusion, the convex portion 312 can easily press the vicinity of the center of the lower surface of the battery cell 10. In addition, the amount of upward pressure applied to the battery cell 10 can be easily controlled by gradually increasing the amount of upward protrusion from the periphery to the center. By doing this, the gas generated inside the battery cell 10 is unlikely to stay at the center of the battery cell 10 and easily move to the periphery of the battery cell 10. By the gas moving to the periphery inside the battery cell 10, an increase in internal resistance of the battery cell 10 can be suppressed. That is, when the gas moves to the periphery inside the battery cell 10, the gas is less likely to be present between the cell electrodes provided inside the battery cell 10, so that stable charge and discharge performance can be exhibited.

  The cross-sectional shape of the convex portion 312 may be a shape including a plurality of ribs 314 projecting upward, as illustrated in FIG. 12C. The shape in which the convex portion 312 includes the rib 314 is also referred to as a rib shape. By including the plurality of ribs 314 in the protrusion 312, the rigidity of the protrusion 312 can be enhanced. By increasing the rigidity of the convex portion 312, the bottom surface 310 is unlikely to be deformed even if the bottom surface of the battery cell 10 is pressed, and the entire bottom surface of the battery cell 10 can be stably pressed.

  As shown in FIG. 13, the cross-sectional shape of the convex portion 62 of the restraint plate 60 may be various shapes. The cross-sectional shape of the convex portion 62 is not limited to the shape illustrated in FIG. 13, and may be other various shapes. The cross-sectional shape of the convex portion 62 may be an offset shape as illustrated in FIG. 13 (A). The cross-sectional shape of the convex part 62 may be a camber shape, as illustrated in FIG. 13 (B). The cross-sectional shape of the convex portion 62 may be a shape including a plurality of downwardly projecting ribs 63 as illustrated in FIG. 13C. The advantage when the cross-sectional shape of the convex portion 62 is each shape is the same as or similar to the advantage when the convex portion 312 of the bottom surface 310 is each shape.

  The restraint plate 60 and the bottom surface 310 pressurize the stacked battery cells 10 through the openings 22 and 32 of the cell case. That is, the cell case is not directly pressurized by the restraint plate 60 and the bottom surface 310. When the cell case is not pressurized, the cell case is less likely to bend. As a result, the cell case is less likely to be damaged.

  The rigidity of the restraint plate 60 can be improved by the restraint plate 60 containing a metal material. By holding the battery cell 10 in which the restraint plates 60 having high rigidity are stacked from both upper and lower sides, the pressure retention can be improved. As a result, the battery cell 10 does not easily expand in the direction in which the battery cells 10 are stacked, and the vertical position of the battery cell 10 can be regulated. The electrical insulation can be improved by the restraint plate 60 including a resin material or a metal material to which an electrically insulating material is applied. When the restraint plate 60 includes a resin material, the battery assembly 1 can be reduced in weight and manufactured at low cost.

  By pressurizing the battery cell 10 near the center of the upper surface and the lower surface of the holding portion 18, gas generated inside the battery cell 10 can be collected in a peripheral portion near the sealing portion 19. When the pressure of the gas generated inside the battery cell 10 exceeds a predetermined value, the gas may be released from the sealing portion 19 to the outside of the battery cell 10. The gas is likely to be released to the outside of the battery cell 10 by collecting the gas in the peripheral portion close to the sealing portion 19. That is, when the battery cell 10 is pressurized near the center of the upper surface and the lower surface of the holding portion 18, the gas is easily released to the outside of the battery cell 10. As a result, the reliability of the battery cell 10 can be improved.

  By providing the insulating sheet 50 in the battery module 100, electrical insulation between the restraint plate 60 and the internal battery cells 10 can be secured.

  The symmetry of the cell case can be improved by the positive electrode tab 12p and the negative electrode tab 12n of the battery cell 10 protruding in opposite directions along the front-rear direction. By doing this, the cell case can be formed in a well-balanced manner.

  It will be apparent to those skilled in the art that the present invention can be realized in other predetermined forms other than the above described embodiment without departing from the spirit or essential characteristics thereof. Thus, the foregoing description is illustrative and not restrictive. The scope of the invention is defined by the appended claims rather than by the foregoing description. Some of the changes that come within the scope of the equivalents are intended to be embraced therein.

  The positive electrode tab 12p and the negative electrode tab 12n of the battery cell 10 have been described as projecting in opposite directions along the front-rear direction, but the invention is not limited thereto. As illustrated in FIG. 14, the positive electrode tab 12 p and the negative electrode tab 12 n may be formed on the same surface. In this case, from the first outer surface 11, the positive electrode tab 12p and the negative electrode tab 12n may be protruded forward in an adjacent arrangement. The first cell case 20 and the second cell case 30 may have any configuration that can be accommodated in the state where the battery cells 10 illustrated in FIG. 14 are stacked. The plurality of battery cells 10 may be stacked such that the positions of the positive electrode tab 12p and the negative electrode tab 12n in the left-right direction in the adjacent battery cells 10 are alternately arranged.

  When the positive electrode tab 12p and the negative electrode tab 12n are formed on the same surface, the slits 34 through which the electrode tab 12 of the second cell case 30 penetrates can be concentrated on one outer surface such as the front surface. The number of assembling steps of the battery module 100 can be reduced by projecting the electrode tab 12 to one side. As a result, the productivity of the battery assembly 1 can be improved. Also, the opposite outer surface can be made flat by bringing the electrode tab 12 out only to one outer surface. By doing this, the length in the front-rear direction of the battery module 100 can be shortened by the length by which the positive electrode tab 12 p or the negative electrode tab 12 n protrudes from the cell case. As a result, the battery assembly 1 can be miniaturized as a whole.

  In the assembled battery 1, the insulating sheet 50 and the restraint plate 60 may be provided only at one end of the first cell case 20 and the second cell case 30 in the vertical direction. By doing this, the number of parts of the assembled battery 1 can be reduced. As a result, the productivity of the battery assembly 1 can be improved.

1 assembled battery 10 battery cell 11 first outer surface 12 (12p, 12n) electrode tab (positive electrode tab, negative electrode tab)
13 second outer surface 14 third outer surface 15 adhesive layer 16 exterior member 17 tab side surface 18 holding portion 19 sealing portion 20 first cell case 22 opening 23 partition plate 30 second cell case 32 opening 33 partition plate 34 slit 40 tab Between bus bar 41 total plus bus bar 42 total minus bus bar 50 insulation sheet 60 restraint plate 62 convex portion 63 rib 64 restraint plate fastening member 66 fastening portion 70 heat dissipation plate 72 hole 80 bus bar cover 90 jig 92 boss 100 battery module 200 accessory module 210 accessory machine Bases 212 and 214 Fastening part 220 Relay 221 Fastening hole 230 Current sensor 231 Fastening hole 240 Fuse 241 Fastening hole 250 Copper bus bar 251 Fastening hole 252 Fastening member 260 Substrate 261 Fastening hole 262 Fastening member 270 Fastening member 300 Lower case 310 Bottom surface 312 Convexity 314 Ribs 320, 3 30, 340 Fastening part 400 Upper case 410 Plus output terminal 412 Plus output terminal bus bar 414 Fastening hole 420 Minus output terminal 422 Minus output terminal bus bar 424 Fastening hole 430 Connector 440 Gas discharge part 442 Gas cover 444 Breather 450 Fastening part

Claims (8)

A plurality of battery cells stacked along a predetermined direction;
A cell case for housing the battery cell;
A restraint plate attached to the cell case ;
A case for housing the cell case , and
The cell case has an opening at each end of the predetermined direction,
The restraint plate pressurizes the battery cell through the opening from the side of one end of the predetermined direction ,
The case has a bottom and
An assembled battery, wherein the bottom surface of the case is pressing the battery cell through the opening from the side opposite to the side where the restraint plate presses the battery cell .   The assembled battery according to claim 1, further comprising a first insulating layer positioned between the restraint plate and the battery cell. Further comprising, assembled battery according to claim 1 or 2 and the second insulating layer located between the bottom surface and the battery cell of the case. The shape of the portion pressing the battery cell on the bottom surface of the case includes at least one of a camber shape, an offset shape in which a part of the surface protrudes uniformly upward , and a rib shape. An assembled battery according to any one of Items 1 to 3 . The assembled battery according to any one of claims 1 to 4 , wherein the case is made of at least one of a metal and a resin. The assembled battery according to claim 2 , wherein the first insulating layer is an insulating member that the battery cell has in a surface layer.   The assembled battery according to claim 3, wherein the second insulating layer is an insulating member that the battery cell has in a surface layer. The shape of the portion pressing the battery cell of the restraint plate includes at least one of a camber shape, an offset shape in which a part of the surface projects uniformly upward , and a rib shape. The assembled battery according to any one of 1 to 7.