JP7054892B2 - Assembled battery and manufacturing method of assembled battery - Google Patents

Description

The present invention relates to an assembled battery and a method for manufacturing the assembled battery.

In recent years, batteries have been used for various purposes, and in particular, large-capacity batteries have been used for applications such as power sources for electric vehicles and power storage.
When using a single battery, the voltage of the battery may be lower than the voltage required by the device. In such a case, it is necessary to connect a plurality of batteries in series to raise the supply voltage to a desired voltage. In addition, a single battery may not be able to supply a sufficient amount of electric power required by a device. In such a case, it is necessary to connect a plurality of batteries in parallel to increase the amount of power supplied to a desired amount. For this reason, a battery box or an assembled battery in which a plurality of batteries are connected in series or in parallel is provided, and power is supplied to the device from these.

A method of manufacturing an assembled battery by joining terminals of two adjacent cell cells is known (see, for example, Patent Document 1). In such a forming method, when a complicated assembled battery in which series connection and parallel connection are combined is manufactured, it is necessary to provide a new conductor, which may increase the manufacturing cost. In addition, it becomes complicated to attach a detection line for detecting the voltage of each cell, which increases the manufacturing cost.
A method for manufacturing an assembled battery in which a plurality of cells are connected by a flexible printed wiring board (FPC) is known (see, for example, Patent Document 2). By using FPC, it becomes possible to connect a single battery in a complicated manner. Further, the detection line can be provided in the FPC, and the manufacturing cost can be reduced.

Japanese Unexamined Patent Publication No. 2013-239293 Patent No. 6115265

In the conventional method of manufacturing an assembled battery in which a plurality of cells are connected by FPC, the connection portion of the FPC and the terminal of the cell are connected by soldering, so that the bonding strength is not sufficient and the assembled battery structure is not sufficient. There are problems such as being restricted.
The present invention has been made in view of such circumstances, and provides an assembled battery which has sufficient bonding strength, is easy to design an assembled battery, and can be manufactured at a reduced manufacturing cost.

The present invention includes a plurality of battery cells and a flexible printed wiring board, each battery cell includes a plate-shaped terminal extending from the inside of the exterior body to the outside, and the plurality of battery cells have the flexible printed circuit board. The flexible printed wiring board is connected in series or in parallel by a wiring board, and the flexible printed wiring board includes a plate-shaped flying lead portion in which at least a part thereof is connected to a laminated structure of the flexible printed wiring board, and the terminal and the flying lead portion are Provided is an assembled battery characterized in that the surfaces are joined to each other.

The flexible printed wiring board included in the assembled battery of the present invention includes a plate-shaped flying lead portion in which at least a part thereof is connected to a laminated structure of the flexible printed wiring boards. This flying lead portion has a structure in which one end is fixed to a laminated structure of a flexible printed wiring board and the other end can move. Therefore, it is possible to bend the flying lead portion so that the plate-shaped terminal extending from the inside to the outside of the outer body of the battery cell overlaps with the flying lead portion. Therefore, it is possible to superimpose the terminals of the battery cell and the flying lead portion on each surface and join them by ultrasonic welding, resistance welding, laser welding, etc., and sufficient joining strength can be obtained, and the manufacturing cost can be obtained. Can be reduced. Further, after joining the terminal of the battery cell and the flying lead portion, the flying lead portion can be bent back to the original position, which facilitates the design of the assembled battery.

It is a schematic perspective view of the assembled battery of one Embodiment of this invention. It is a schematic perspective view of the assembled battery in the broken line AA of FIG. (A) is a schematic enlarged view of the assembled battery in the range B surrounded by the broken line in FIG. 2, and (b) is a schematic enlarged view of the assembled battery in the range C surrounded by the broken line in FIG. It is a schematic development view of the flexible printed wiring board included in the assembled battery of one Embodiment of this invention. It is explanatory drawing of the manufacturing method of the assembled battery of one Embodiment of this invention. It is a schematic sectional drawing of the assembled battery of one Embodiment of this invention. It is explanatory drawing of the manufacturing method of the assembled battery of one Embodiment of this invention.

The assembled battery of the present invention includes a plurality of battery cells and a flexible printed wiring board, each battery cell includes a plate-shaped terminal extending from the inside of the exterior body to the outside, and the plurality of battery cells include. The flexible printed wiring board is connected in series or in parallel by the flexible printed wiring board, and the flexible printed wiring board includes a plate-shaped flying lead portion in which at least a part thereof is connected to a laminated structure of the flexible printed wiring board, and the terminal and the flying. The lead portion is characterized in that the surfaces are joined to each other.

It is preferable that the flexible printed wiring board has an opening and the flying lead portion is provided in the opening. As a result, the flying lead portion does not protrude to the outside from the flexible printed wiring board, and the assembled battery can be miniaturized.
This opening is preferably formed in the plane excluding the end of the flexible printed wiring board. This makes it possible to reduce the size of the assembled battery.
It is preferable that the flexible printed wiring board has a power line and a battery state detection line, and the flying lead portion is a part of the power line. This facilitates the arrangement of the battery cells in the assembled battery, and the assembled battery can be miniaturized.
It is preferable that the power line and the battery status detection line are connected inside the flexible printed wiring board. This facilitates the arrangement of the battery cells in the assembled battery, and the assembled battery can be miniaturized.
The power line is preferably a metal plate having a thickness of 100 μm or more and 300 μm or less. As a result, a relatively large current can be passed through the power line, and the output of the assembled battery can be increased.

It is preferable that each battery cell has a flat plate shape, and the plurality of battery cells are stacked in the thickness direction of the battery cells. This makes it possible to reduce the size of the assembled battery.
The battery cell includes an electrode assembly inside the exterior, and the electrode assembly has a laminated structure in which at least one positive electrode, at least one negative electrode, and at least one separator are stacked, and a positive electrode current collecting sheet is overlapped from the laminated structure. It is provided with a positive electrode extending portion extending from the laminated structure and a negative electrode extending portion extending from the laminated structure by overlapping negative electrode current collecting sheets. It is preferable that the terminal or the exterior body is bent between the terminals. This makes it possible to reduce the size of the assembled battery.
The assembled battery of the present invention preferably includes a plurality of battery groups, each battery group preferably has a structure in which a plurality of battery cells are stacked in the thickness direction, and a plurality of battery cells included in each battery group. Is preferably connected in series or in parallel by the flexible printed wiring board, and it is preferable that a plurality of battery groups are connected by the same flexible printed wiring board. This makes it possible to arrange a plurality of battery cells in several groups, which facilitates the design of an assembled battery.
The two adjacent battery groups are the first part of the flexible printed wiring board to which a plurality of battery cells included in the first battery group are connected, and the flexible printed wiring board to which the plurality of battery cells included in the second battery group are connected. It is preferable that the second portion of the flexible printed wiring board is arranged so as to face each other, and it is preferable that an insulating partition wall is provided between the first portion and the second portion of the flexible printed wiring board. This makes it possible to prevent short circuits from occurring between adjacent battery groups.

The present invention comprises a step of bending a plate-shaped flying lead portion which is at least partially connected to a laminated structure of flexible printed wiring boards, and a plate-shaped terminal and a flying lead extending from the inside to the outside of the battery cell exterior. Provided is a method for manufacturing an assembled battery, which includes a step of overlapping and joining the portions and a step of bending back the flying lead portion.
Further, the step of bending back the flying lead portion is preferably a step involving bending of the terminal or the exterior body.

Hereinafter, an embodiment of the present invention will be described with reference to the drawings. The configurations shown in the drawings and the following description are illustrative, and the scope of the present invention is not limited to those shown in the drawings and the following description.

1 to 7 are drawings relating to the assembled battery of the present embodiment, and the details are the same as those described in the above drawings.
The assembled battery 60 of the present embodiment includes a plurality of battery cells 2 and a flexible printed wiring board 3, and each battery cell 2 has plate-shaped terminals 4 and 5 extending from the inside of the exterior body 16 to the outside. A plurality of battery cells 2 are connected in series or in parallel by a flexible printed wiring board 3, and the flexible printed wiring board 3 is a plate-shaped flying lead in which at least a part thereof is connected to a laminated structure of the flexible printed wiring board 3. The portion 6 is provided, and the terminals 4 and 5 and the flying lead portion 6 are characterized in that the surfaces thereof are joined to each other.
The method for manufacturing the assembled battery 60 of the present embodiment includes a step of bending a plate-shaped flying lead portion 6 which is at least partially connected to a laminated structure of a flexible printed wiring board 3, and a step of bending the inside of the exterior body 16 of the battery cell 2. The process includes a step of superimposing and joining the plate-shaped terminals 4 and 5 extending to the outside and the flying lead portion 6, and a step of bending back the flying lead portion 6.

The assembled battery 60 may include a battery group in which a plurality of battery cells are stacked in the thickness direction. For example, in the assembled battery 60 shown in FIGS. 1 and 2, five battery cells 2a to 2e are stacked.
Further, the assembled battery 60 may have a plurality of battery groups in which a plurality of battery cells 2 are stacked, and the plurality of battery groups may be arranged side by side. For example, in the assembled battery 60 shown in FIGS. 7B to 7D, a first battery group in which five battery cells 2 are stacked, a second battery group in which five battery cells 2 are stacked, and two A third battery group in which two battery cells 2 are stacked is arranged side by side.
The assembled battery 60 may include a housing 35 that accommodates a plurality of battery cells 2. The material of the housing 35 can be an insulating material such as plastic. Further, the housing 35 may have a partition wall 36 arranged between a first battery group in which a plurality of battery cells 2 are stacked and a second battery group in which a plurality of battery cells 2 are stacked. .. This makes it possible to prevent a short circuit between two adjacent battery cells 2.

The battery cell 2 included in the assembled battery 60 of the present embodiment is preferably a sealed battery. A sealed battery is a battery having a sealed structure in which the electrolyte is shielded from the outside air and liquid does not leak during storage or discharging. The battery cell 2 may be a secondary battery or a non-aqueous electrolyte secondary battery. The battery cell 2 is, for example, a lithium ion battery, a sodium ion battery, a lead storage battery, a nickel / hydrogen battery, a nickel / cadmium battery, or the like. The shape of the battery cell 2 may be cylindrical or plate-shaped, but a plate-shaped battery is preferable. The plate-shaped battery may be a thin battery such as a square battery having an exterior made of metal or resin, or a pouch type battery having an exterior such as a laminated film. Further, as the terminal shape, it is preferable that the plate-shaped terminal extends from the inside of the exterior body to the outside. The terminal is a positive electrode terminal 4 or a negative electrode terminal 5.

For example, the shape of the battery cell 2 can be a flat rectangular parallelepiped. In this case, the battery cell 2 can have a wider surface, an upper surface and a lower surface, and can have four side surfaces around it. A positive electrode extending portion 25 and a negative electrode extending portion 26 can be provided inside each of the two facing side surfaces out of the four side surfaces.

The exterior body 16 is a container that houses the electrode assembly 12 and the electrolyte 15. The material of the exterior body 16 is, for example, a laminated film. The exterior body 16 can be provided so as to form a closed space inside which accommodates the electrode assembly 12 and the electrolyte 15. When the material of the exterior body 16 is a laminated film, the battery cell 2 is a pouch type battery. In this case, the exterior body 16 can have a welded portion in which a laminated film is laminated and welded on the peripheral portion thereof. Further, on the peripheral edge of the exterior body 16, a positive electrode side sealing portion 51 having laminated films bonded on both sides of the positive electrode terminal 4 and a negative electrode side sealing portion 52 having laminated films bonded to both sides of the negative electrode terminals 5 are provided. Can be done. By arranging the positive electrode terminal 4 and the negative electrode terminal 5 in this way, the terminals 4 and 5 are in a state of extending from the inside of the exterior body 16 to the outside. The laminated film is, for example, a resin film laminated on both sides of a metal film. The thickness of the laminated film can be, for example, 50 to 200 μm.
The exterior body 16 preferably has a bag-shaped structure of the laminated film. As a result, when the positive electrode bent portion 30 or the negative electrode bent portion 31 is formed, the exterior body 16 can also be folded, and the battery cell 2 can be easily miniaturized.

The electrode assembly 12 has a laminated structure 10 in which at least one positive electrode 7, at least one negative electrode 8, and at least one separator 9 are superposed. The laminated structure 10 is a portion where the positive electrode 7, the negative electrode 8, and the separator 9 overlap. Further, the electrode assembly 12 has a positive electrode extending portion 25 extending from the laminated structure 10 with the positive electrode current collecting sheet 18 overlapping, and a negative electrode extending portion 26 extending from the laminated structure 10 with the negative electrode current collecting sheet 22 overlapping. And have.
The electrode assembly 12 may have a stack type structure in which a plurality of positive electrodes 7, a plurality of negative electrodes 8, and a separator 9 are stacked. In this case, the laminated structure 10 is a portion in which a plurality of positive electrodes 7 and a plurality of negative electrodes 8 are alternately stacked via a separator 9. When the electrode assembly 12 has a stack structure, the electrode assembly 12 has a structure in which a sheet-shaped positive electrode 7 and a sheet-shaped negative electrode 8 are alternately stacked with a separator 9 interposed therebetween. Further, each of the stacked positive electrodes 7 is a separate positive electrode, and each of the stacked negative electrodes 8 is a separate negative electrode. Further, the plurality of positive electrodes 7 included in the electrode assembly 12 can have substantially the same shape, and the plurality of negative electrodes 8 included in the electrode assembly 12 can have substantially the same shape. For example, the electrode assembly 12 may include a single separator 9 folded in a zigzag manner, and a positive electrode 7 and a negative electrode 8 arranged in each valley groove of the separator 9 and alternately arranged via the separator 9. can. Further, separate separators 9 may be arranged between the positive electrode 7 and the negative electrode 8. The number of layers of the positive electrode 7 or the negative electrode 8 included in the electrode assembly 12 can be appropriately designed according to the required battery capacity. Further, the battery cell 2 may have a plurality of electrode aggregates 12.
Further, the electrode assembly 12 may have a winding structure in which the positive electrode 7, the negative electrode 8, and the separator 9 are overlapped and wound. In this case, the laminated structure 10 is a portion where the positive electrode 7, the negative electrode 8, and the separator 9 overlap from the winding shaft toward the outer periphery. Further, the electrode assembly 12 may have a flat winding structure.

The positive electrode 7 includes a positive electrode current collector sheet 18 and a positive electrode active material layer 19 provided on the positive electrode current collector sheet 18. The positive electrode 7 can have a square or rectangular sheet shape. The positive electrode 7 can be produced, for example, by forming a positive electrode active material layer 19 on both sides of a rectangular positive electrode current collector sheet 18. The positive electrode 7 can have a connection portion (positive electrode current collector sheet 18) connected to the positive electrode side clip 46 or the positive electrode terminal 4, and this connection portion is provided on both sides of the positive electrode current collector sheet 18 at the end of the positive electrode 7. It can be provided by not forming the positive electrode active material layer 19. Further, it is also possible to provide a connecting portion by forming an ear portion at one end of the positive electrode current collecting sheet 18 and not forming the positive electrode active material layer 19 at the ear portion. This connecting portion extends from the laminated structure 10 of the electrode assembly 12 to form the positive electrode extending portion 25.

The positive electrode current collecting sheet 18 is not particularly limited as long as it has electrical conductivity and can be provided with the positive electrode active material layer 19 on the surface, but is, for example, a metal foil. Aluminum foil is preferable. The thickness of the positive electrode current collector sheet 18 is, for example, 10 μm to 40 μm.
The positive electrode active material layer 19 can be formed on the positive electrode current collector sheet 18 by adding a conductive agent, a binder, or the like to the positive electrode active material and applying a coating method or the like. The positive electrode active material is, for example, a lithium transition metal composite oxide capable of reversibly occluding and releasing lithium ions. Specifically, the positive electrode active materials are LiCoO ₂ , LiNiO ₂ , LiNi _x Co _1-x O ₂ (x = 0.01 to 0.99), LiMnO ₂ , LiMn ₂ O ₄ , LiCo _x Mn _y Ni _z . O ₂ (x + y + z = 1) or olivine type LiFePO ₄ or Li _x Fe _{1- y} My PO ₄ (provided that 0.05 ≦ x ≦ 1.2, 0 ≦ y ≦ 0.8, and M is Mn. , Cr, Co, Cu, Ni, V, Mo, Ti, Zn, Al, Ga, Mg, B, Nb) and the like can be used alone or in admixture. can.

The negative electrode 8 includes a negative electrode current collector sheet 22 and a negative electrode active material layer 23 provided on the negative electrode current collector sheet 22. The negative electrode 8 can have a square or rectangular sheet shape. The negative electrode 8 can be manufactured, for example, by forming the negative electrode active material layer 23 on both sides of the rectangular negative electrode current collector sheet 22. The negative electrode 8 can have a connection portion (negative electrode current collector sheet 22) connected to the negative electrode side clip 47 or the negative electrode terminal 5, and this connection portion is provided on both sides of the negative electrode current collector sheet 22 at the end of the negative electrode 8. It can be provided by not forming the negative electrode active material layer 23. Further, it is also possible to provide a connecting portion by forming an ear portion at one end of the negative electrode current collecting sheet 22 and not forming the negative electrode active material layer 23 at the ear portion. This connecting portion extends from the laminated structure 10 of the electrode assembly 12 to form the negative electrode extending portion 26.

The negative electrode current collecting sheet 22 is not particularly limited as long as it has electrical conductivity and can be provided with the negative electrode active material layer 23 on the surface, but is, for example, a metal foil. Copper foil is preferable. The thickness of the negative electrode current collector sheet 22 is, for example, 10 μm to 40 μm.
The negative electrode active material layer 23 can be formed on the negative electrode current collector sheet 22 by adding a conductive agent, a binder, or the like to the negative electrode active material and applying a coating method or the like. As the negative electrode active material, for example, in the case of a lithium ion secondary battery, graphite, partially graphitized carbon, hard carbon, soft carbon, LiTIO ₄ , Sn alloy and the like can be used alone or in combination of two or more.

The positive electrode extending portion 25 is a portion where only the positive electrode current collecting sheet 18 extends from the laminated structure 10, and in the positive electrode extending portion 25, the positive electrode active material layer 19 is formed on the positive electrode current collecting sheet 18. not. Further, in the positive electrode extending portion 25, the positive electrode current collecting sheet 18 overlaps. The portion extending from the laminated structure 10 may be an edge portion of the positive electrode current collector sheet 18, an ear portion provided on the positive electrode current collector sheet 18, or an attached lead or the like. Further, the positive electrode extending portion 25 may be a portion where the positive electrode current collecting sheet 18 extends from the side surface of the laminated structure 10, or may be an ear portion provided on the positive electrode current collecting sheet 18, and may be attached. It may be a lead or the like.

When the electrode assembly 12 has a stack type structure, the positive electrode extending portion 25 is a portion extending from each positive electrode 7 included in the laminated structure 10 so that the positive electrode current collecting sheet 18 overlaps. In the positive electrode extending portion 25, since the negative electrode 8 and the separator 9 are not arranged between the overlapping positive electrode current collecting sheets 18, the overlapping positive electrode collecting sheets 18 can be bundled by the positive electrode side clip 46, and the laminated structure is obtained. Each positive electrode 7 included in 10 and the positive electrode side clip 46 can be electrically connected via the positive electrode extending portion 25.
When the electrode assembly 12 has a wound structure, the positive electrode extending portion 25 is a portion extending from the positive electrode 7 included in the spiral laminated structure 10 so that the positive electrode current collecting sheet 18 overlaps. In the positive electrode extending portion 25, since the negative electrode 8 and the separator 9 are not arranged between the overlapping positive electrode current collecting sheets 18, the overlapping positive electrode collecting sheets 18 can be bundled by the positive electrode side clip 46, and the laminated structure is obtained. The positive electrode 7 included in the 10 and the positive electrode side clip 46 can be electrically connected via the positive electrode extending portion 25.
Further, the overlapping positive electrode current collector sheets 18 included in the positive electrode extending portion 25 may be bonded to the positive electrode terminal 4 without providing the positive electrode side clip 46. For example, the positive electrode terminal 4 and the positive electrode current collector sheet 18 can be overlapped and ultrasonically welded.

The negative electrode extending portion 26 is a portion where only the negative electrode current collecting sheet 22 extends from the laminated structure 10, and in the negative electrode extending portion 26, the negative electrode active material layer 23 is formed on the negative electrode current collecting sheet 22. not. Further, in the negative electrode extending portion 26, the negative electrode current collector sheet 22 overlaps. The portion extending from the laminated structure 10 may be an edge portion of the negative electrode current collector sheet 22, an ear portion provided on the negative electrode current collector sheet 22, or an attached lead or the like. Further, the negative electrode extending portion 26 may be a portion where the negative electrode current collecting sheet 22 extends from the side surface of the laminated structure 10, or may be an ear portion provided on the positive electrode current collecting sheet 18, and may be attached. It may be a lead or the like. The side surface provided with the negative electrode extending portion 26 may be the side surface opposite to the side surface provided with the positive electrode extending portion 25.

When the electrode assembly 12 has a stack type structure, the negative electrode extending portion 26 is a portion extending from each negative electrode 8 included in the laminated structure 10 so that the negative electrode current collecting sheet 22 overlaps. In the negative electrode extending portion 26, since the positive electrode 7 and the separator 9 are not arranged between the overlapping negative electrode current collecting sheets 22, the overlapped negative electrode current collecting sheets 22 can be bundled by the negative electrode side clip 47, and the laminated structure. Each negative electrode 8 included in 10 and the negative electrode side clip 47 can be electrically connected via the negative electrode extending portion 26.
When the electrode assembly 12 has a wound structure, the negative electrode extending portion 26 is a portion extending from the negative electrode 8 included in the spiral laminated structure 10 so that the negative electrode current collecting sheet 22 overlaps. In the negative electrode extending portion 26, since the positive electrode 7 and the separator 9 are not arranged between the overlapping negative electrode current collecting sheets 22, the overlapped negative electrode current collecting sheets 22 can be bundled by the negative electrode side clip 47, and the laminated structure. The negative electrode 8 included in the 10 and the negative electrode side clip 47 can be electrically connected via the negative electrode extending portion 26.
Further, the overlapping negative electrode current collector sheets 22 included in the negative electrode extending portion 26 may be bonded to the negative electrode terminal 5 without providing the negative electrode side clip 47. For example, the negative electrode terminal 5 and the negative electrode current collector sheet 22 can be overlapped and ultrasonically welded.

The separator 9 has a sheet shape and is arranged between the positive electrode 7 and the negative electrode 8. The separator 9 is not particularly limited as long as it can prevent a short-circuit current from flowing between the positive electrode 7 and the negative electrode 8 and is permeable to the electrolyte, but is, for example, a microporous film of polyolefin or polyethylene. be able to.

As the electrolyte 15, carbonates, lactones, ethers, esters and the like can be used as the solvent, and two or more of these solvents can be mixed and used. Among these, it is particularly preferable to use a mixture of cyclic carbonate and chain carbonate. The electrolyte 15 is free of lithium salt solutes such as, for example, LiCF ₃ SO ₃ , LiAsF ₆ , LiClO ₄ , LiBF ₄ , LiPF ₆ , LiBOB, LiN (CF ₃ SO ₂ ) ₂ , LiN (C ₂ F ₅ SO ₂ ). It is a solution dissolved in an aqueous solvent. In addition, if necessary, one or more additives such as VC (vinylene carbonate), PS (propane sultone), VEC (vinyl ethyl sultone), PRS (propene sultone), FEC (fluoroethylene carbonate), and flame retardant may be used. It may be mixed and blended.

The positive electrode side clip 46 is provided so as to overlap and bundle the portions (connecting portion, positive electrode extending portion 25) of the positive electrode current collecting sheet 18 where the positive electrode active material layer 19 is not provided. Further, the negative electrode side clip 47 is provided so as to overlap and bundle the portions (connecting portion, negative electrode extending portion 26) of the negative electrode current collecting sheet 22 where the negative electrode active material layer 23 is not provided.
The positive electrode side clip 46 or the negative electrode side clip 47 may be ultrasonically welded together with the positive electrode current collector sheet 18 or the negative electrode current collector sheet 22 sandwiched in layers. For example, the positive electrode side clip 46 or the negative electrode side clip 47 can be integrated with the positive electrode current collecting sheet 18 or the negative electrode current collecting sheet 22 sandwiched by stacking the positive electrode side clip 46 or the negative electrode side clip 47 by ultrasonic welding.

The positive electrode side clip 46 or the negative electrode side clip 47 is made of a conductive material. As a result, the battery cell 2 can be charged and discharged via the positive electrode side clip 46 or the negative electrode side clip 47. When the positive electrode side clip 46 and the negative electrode side clip 47 are made of a metal plate, the thickness of the metal plate can be, for example, 100 μm to 500 μm.

The positive electrode terminal 4 is a member that is electrically connected to the positive electrode 7 inside the exterior body 16 and serves as a terminal on the positive electrode side of the battery cell 2. The portion of the positive electrode terminal 4 located inside the exterior body 16 can be joined to the positive electrode side clip 46 or the positive electrode extending portion 25. The positive electrode terminal 4 can be joined to the positive electrode side clip 46 by superimposing the positive electrode terminal 4 and the positive electrode side clip 46 and performing ultrasonic welding. The positive electrode terminal 4 can be a metal plate. Further, when the material of the positive electrode current collector sheet 18 and the positive electrode side clip 46 is aluminum, the positive electrode terminal 4 can be an aluminum plate. The thickness of the positive electrode terminal 4 can be, for example, 100 μm to 500 μm.

The positive electrode terminal 4 and the exterior body 16 can form a positive electrode side sealing portion 51 in which the exterior body 16 is adhered to the positive electrode terminal 4. The positive electrode side sealing portion 51 forms a peripheral edge portion of the exterior body 16 together with the welding portion and the negative electrode side sealing portion 52, and this peripheral edge portion forms the electrode aggregate 12, the electrolyte 15, and the positive electrode side inside the exterior body 16. It forms a closed space in which the clip 46 and the negative electrode side clip 47 are arranged. Further, by providing the positive electrode side sealing portion 51, a part of the positive electrode terminal 4 can be located inside the exterior body 16, and the other part of the positive electrode terminal 4 can be located outside the exterior body 16. Therefore, the positive electrode terminal 4 extends from the inside of the exterior body 16 to the outside. The positive electrode side sealing portion 51 may be formed by adhering the positive electrode terminal 4 and the exterior body 16 via an adhesive layer, or may be formed by welding the exterior body 16 to the positive electrode terminal 4.
The portion of the positive electrode terminal 4 located outside the exterior body 16 is joined to the flying lead portion 6 of the flexible printed wiring board 3. Therefore, the electrode assembly 12 arranged in the closed space inside the exterior body 16 and the flexible printed wiring board 3 can be electrically connected via the positive electrode terminal 4, and the battery cell 2 can be electrically connected via the positive electrode terminal 4. Can be charged and discharged.
The shape of the positive electrode terminal 4 can be, for example, a plate shape or a band shape. In this case, one end of the positive electrode terminal 4 can be joined to the positive electrode side clip 46 or the positive electrode extending portion 25, and the other end of the positive electrode terminal 4 can be joined to the flying lead portion 6. Then, the positive electrode side sealing portion 51 can be provided between them.

The negative electrode terminal 5 is a member that is electrically connected to the negative electrode 8 inside the exterior body 16 and serves as a terminal on the negative electrode side of the battery cell 2. The portion of the negative electrode terminal 5 located inside the exterior body 16 can be joined to the negative electrode side clip 47 or the negative electrode extending portion 26. The negative electrode terminal 5 can be joined to the negative electrode side clip 47 by superimposing the negative electrode terminal 5 and the negative electrode side clip 47 and performing ultrasonic welding. The negative electrode terminal 5 can be a metal plate. Further, when the material of the negative electrode current collector sheet 22 and the negative electrode side clip 47 is copper, the negative electrode terminal 5 can be a copper plate. The thickness of the negative electrode terminal 5 can be, for example, 100 μm to 500 μm.

The negative electrode terminal 5 and the exterior body 16 can form a negative electrode side sealing portion 52 in which the exterior body 16 is adhered to the negative electrode terminal 5. The negative electrode side sealing portion 52 forms a peripheral edge portion of the exterior body 16 together with the welding portion and the positive electrode side sealing portion 51, and this peripheral edge portion forms the electrode aggregate 12, the electrolyte 15, and the positive electrode side inside the exterior body 16. It forms a closed space in which the clip 46 and the negative electrode side clip 47 are arranged. Further, by providing the negative electrode side sealing portion 52, a part of the negative electrode terminal 5 can be located inside the exterior body 16, and the other part of the negative electrode terminal 5 can be located outside the exterior body 16. Therefore, the negative electrode terminal 5 extends from the inside of the exterior body 16 to the outside. The negative electrode side sealing portion 52 may be formed by adhering the negative electrode terminal 5 and the exterior body 16 via an adhesive layer, or may be formed by welding the exterior body 16 to the negative electrode terminal 5.
The portion of the negative electrode terminal 5 located outside the exterior body 16 is joined to the flying lead portion 6 of the flexible printed wiring board 3. Therefore, the electrode assembly 12 arranged in the closed space inside the exterior body 16 and the flexible printed wiring board 3 can be electrically connected via the negative electrode terminal 5, and the battery cell 2 can be electrically connected via the negative electrode terminal 5. Can be charged and discharged.
The shape of the negative electrode terminal 5 can be, for example, a band shape. In this case, one end of the negative electrode terminal 5 can be joined to the negative electrode side clip 47 or the negative electrode extending portion 26, and the other end of the negative electrode terminal 5 can be joined to the flying lead portion 6. Then, the negative electrode side sealing portion 52 can be provided between them.

The positive electrode extending portion 25 (positive electrode current collecting sheet 18) can have a positive electrode bent portion 30 formed by overlapping and bending the positive electrode current collecting sheets 18. Further, the negative electrode extending portion 26 (negative electrode current collecting sheet 22) can have a negative electrode bent portion 31 formed by overlapping and bending the negative electrode current collecting sheet 22. By providing the positive electrode bent portion 30 and the negative electrode bent portion 31, the portion of the positive electrode current collecting sheet 18 where the positive electrode active material layer 19 is not formed (positive electrode extending portion 25) and the negative electrode active material layer 23 of the negative electrode current collecting sheet 22 are provided. The portion (negative electrode extending portion 26) in which the is not formed can be folded, and the battery cell 2 can be miniaturized.

The positive electrode bent portion 30 is not particularly limited as long as it is a bent portion provided between the end portion of the laminated structure 10 and the joint portion 11 of the positive electrode terminal 4 and the flying lead portion 6, but the laminated electrode aggregate 12 is laminated. The positive electrode terminal 4 can be provided so as to be arranged along the side surface where the positive electrode extending portion 25 of the structure 10 is provided. Further, the positive electrode bent portion 30 can be provided so that the positive electrode terminal 4 and the flexible printed wiring board 3 overlap each other. Further, the positive electrode bent portion 30 can be provided so that the positive electrode terminal 4 is arranged along the flexible printed wiring board 3. By providing the positive electrode bent portion 30 in this way, the space between the laminated structure 10 and the flexible printed wiring board 3 can be narrowed, and the assembled battery 60 can be miniaturized.

The negative electrode bent portion 30 is not particularly limited as long as it is a bent portion provided between the end portion of the laminated structure 10 and the joint portion 11 of the negative electrode terminal 5 and the flying lead portion 6, but the laminated electrode aggregate 12 is laminated. The negative electrode terminal 5 can be provided so as to be arranged along the side surface where the negative electrode extending portion 26 of the structure 10 is provided. Further, the negative electrode bent portion 31 can be provided so that the negative electrode terminal 5 and the flexible printed wiring board 3 overlap each other. Further, the negative electrode bent portion 31 can be provided so that the negative electrode terminal 5 is arranged along the flexible printed wiring board 3. By providing the negative electrode bent portion 31 in this way, the space between the laminated structure 10 and the flexible printed wiring board 3 can be narrowed, and the assembled battery 60 can be miniaturized.

When the assembled battery 60 has a battery group in which a plurality of battery cells 2 are stacked, the positive electrode extending portion 25 or the negative electrode extending portion 26 of each battery cell 2 is located on the first side surface side of the battery group, and each battery cell 2 is located. A plurality of battery cells 2 can be stacked so that the positive electrode extending portion 25 or the negative electrode extending portion 26 of the above is located on the second side surface side of the battery group. Further, the flexible printed wiring board 3 can be arranged along the first side surface and the second side surface of the battery group. This makes it possible to easily join the positive electrode terminal 4 and the negative electrode terminal 5 of each battery cell 2 to the flying lead portion 6 of the flexible printed wiring board 3.

The assembled battery 60 includes a flexible printed wiring board (FPC) 3 for connecting a plurality of battery cells 2 in series or in parallel. By connecting a plurality of battery cells 2 with the flexible printed wiring board 3, it is possible to arrange the plurality of battery cells 2 included in the assembled battery 60 in various arrangements, and the shape of the assembled battery 60 can be arranged in various spaces. It will be possible to adapt to.
The flexible printed wiring board 3 is a substrate provided with a metal layer having a wiring pattern formed on a thin and soft insulating base film 48 (insulating film 44). The flexible printed wiring board 3 may be a single-sided FPC having a metal layer provided on one side of the base film 48, or may be a double-sided FPC having a metal layer provided on both sides of the base film 48. It may be a multilayer FPC on which the base film 48 is stacked. The flexible printed wiring board 3 can be provided, for example, as shown in the developed view of FIG.

Electronic components and connectors 43 may be mounted on the flexible printed wiring board 3. Further, the flexible printed wiring board 3 can have a structure (laminated structure) in which a metal layer is sandwiched between the base film 48 and the cover film 49. This metal layer serves as a power line 40 including the flying lead portion 6 and a battery state detection line, here, a voltage detection line 41. Further, this metal layer may be the connection terminals 42a and 42b which are the ends of the power line 40. The insulating film 44 (base film 48 and cover film 49) is, for example, a polyimide film. The material of the metal layer is, for example, copper, aluminum or silver. The thickness of the metal layer is, for example, 100 μm or more and 300 μm or less. A wiring pattern is formed in this metal layer, and includes a power line 40 and a voltage detection line (battery state detection line) 41. When the metal layer is used as the power line 40, it is preferable that the metal layer has a relatively thick thickness. By using a relatively thick metal plate for the metal layer, it becomes possible to pass a relatively large current through the power line 40. Further, since the flying lead portion 6 also has a relatively thick plate shape, the flying lead portion 6 can be easily joined to the positive electrode terminal 4 or the negative electrode terminal 5.
The thickness of the base film 48 or the cover film 49 is, for example, 10 μm or more and 60 μm or less. Further, the adhesive layer may or may not be provided between the metal layer and the base film 48 or between the metal layer and the cover film 49.

The power line 40 is a wiring formed on the flexible printed wiring board 3 through which the discharge current and the charge current of the battery cell 2 flow. The power line 40 can have a pattern in which a plurality of battery cells 2 included in the assembled battery 60 can be connected in series or in parallel. Further, the power line 40 can be provided so as to connect the positive electrode terminal 4 or the negative electrode terminal 5 of at least two battery cells 2 included in the assembled battery 60. Further, since the power line 40 has a relatively large current flowing through it, it has a wider width than the voltage detection line 41. The width of the metal plate (metal layer) of the power line 40 is preferably 5 mm to 20 mm.
The power line 40 has a flying lead portion 6. In the flying lead portion 6, the insulating film 44 on the upper surface and the lower surface of the metal layer is removed, and the metal surface is exposed, so that the upper surface and the lower surface of the flying lead portion 6 have conductivity. The metal layer of the flying lead portion 6 may be surface-treated such as metal plating. The flying lead portion 6 has a structure in which at least a part thereof is connected to the laminated structure of the flexible printed wiring board 3. That is, one end of the flying lead portion 6 is connected to the power line 40 between the base film 48 and the cover film 49, and is fixed to the base film 48 and the cover film 49. The other end of the flying lead portion 6 is not fixed to the base film 48 and the cover film 49. Therefore, the flying lead portion 6 can be bent at the root thereof. When the flexible printed wiring board 3 is bent or folded back when manufacturing the assembled battery, the internal wiring may be damaged, but if only the flying lead portion 6 is bent, it is a metal plate, so that it is damaged. There is no fear.
The flying lead portion 6 can be provided in the opening 45 provided in the flexible printed wiring board 3. The opening 45 is preferably provided at a position not protruding from the surface of the flexible printed wiring board 3, and more preferably provided at a position excluding the end portion in the surface of the flexible printed wiring board.
Further, the flying lead portion 6 may have a cantilever structure (cantilever structure).

The flying lead portion 6 and the positive electrode terminal 4 or the negative electrode terminal 5 of the battery cell 2 are overlapped and joined to form a joined portion 11. Therefore, the power line 40 of the flexible printed wiring board 3 and the battery cell 2 can be electrically connected via the flying lead portion 6, and a plurality of battery cells 2 included in the assembled battery 60 are connected in series by the power line 40. Alternatively, they can be connected in parallel. Further, the flying lead portion 6 can be in the shape of a plate having a width of 5 mm to 20 mm. As a result, the flying lead portion 6 and the positive electrode terminal 4 or the negative electrode terminal 5 can be easily overlapped and joined. The method of forming the joint portion 11 will be described later.
The flexible printed wiring board 3 can have a plurality of flying lead portions 6. The plurality of flying lead portions 6 correspond to and join the positive electrode terminals 4 and the negative electrode terminals 5 of the plurality of battery cells 2 included in the assembled battery 60, respectively.

The power line 40 can have connection terminals 42a and 42b. The connection terminals 42a and 42b are external connection terminals of a plurality of battery cells 2 connected in series or in parallel by a flexible printed wiring board 3. The connection terminals 42a and 42b may be connected to the control unit 38. This makes it possible for the control unit 38 to control the charging / discharging of the assembled battery 60. The control unit 38 may include a fuse or a relay. As a result, when the control unit 38 detects overcharging or overdischarging of the battery cell 2, the electrical connection between the external connection terminal of the assembled battery 60 and the battery can be disconnected, and the safety of the assembled battery 60 can be cut off. Can be improved. The fixing of the connection terminal 42 and the control unit 38 is not particularly limited, but for example, screwing can be used.
Further, the connection terminals 42a and 42b may be connected to external wiring. The metal layers of the connection terminals 42a and 42b may be surface-treated such as metal plating. Here, a case where a part of the power line 40 is a connection terminal 42 is described, but the flexible printed wiring board 3 is equipped with a connector connected to the power line 40, and the power line 40 is a control unit via this connector. It may be connected to 38 or external wiring.

The voltage detection line (battery state detection line) 41 is a wiring for detecting the voltage between the positive electrode terminal 4 and the negative electrode terminal 5 of the battery cell 2 among the wirings formed on the flexible printed wiring board 3. The voltage detection line 41 can have a pattern that can detect the voltage between terminals of each battery cell 2 included in the assembled battery 60. Further, the voltage detection line 41 can be connected to the power line 40 so that the control unit 38 can detect the voltage between the terminals of each battery cell 2. Further, by forming the power line 40 and the voltage detection line 41 other than the flying lead portion 6 inside the flexible printed wiring board 3, it is possible to prevent erroneous contact and erroneous detection. Further, the voltage detection line 41 is provided so as to electrically connect the power line 40 that electrically connects at least two battery cells 2 and the control unit 38. Further, since only a relatively small current flows through the voltage detection line 41, the voltage detection line 41 has a narrower width than the power line 40.
The flexible printed wiring board 3 can have a connector 43 connected to the voltage detection line 41. This connector 43 can be connected to the control unit 38. This makes it possible to detect the terminal voltage of each battery cell 2 included in the assembled battery 60 via the voltage detection line 41 and the connector 43, and overcharge and overdischarge each battery cell 2 during charging and discharging. Can be detected. The control unit 38 is, for example, a battery monitoring unit (BMU).
In this embodiment, the voltage detection line is taken as an example of the battery state detection line 41, but this detection line can be used to detect other battery states such as current detection and temperature detection.

When the assembled battery 60 has a battery group in which a plurality of battery cells 2 are stacked, the first side surface of the battery group in which the positive electrode terminals 4 or the negative electrode terminals 5 of each battery cell 2 are arranged in the vertical direction, and each battery cell 2. The flexible printed wiring board 3 can be arranged along the second side surface of the battery group in which the positive electrode terminal 4 or the negative electrode terminal 5 is arranged in the vertical direction, and the plurality of flying lead portions 6 are the positive electrode terminals 4 arranged in the vertical direction. Alternatively, it can be provided so as to correspond to the negative electrode terminal 5 and to be joined. In this case, the plurality of flying lead portions 6 are arranged in the vertical direction corresponding to the positive electrode terminals 4 or the negative electrode terminals 5 arranged in the vertical direction, and are joined to the positive electrode terminal 4 or the negative electrode terminal 5 at the joint portion 11, respectively. Further, one bent flexible printed wiring board 3 can be arranged along the first side surface and the second side surface of the battery group. As a result, the voltage detection line 41 can be provided on one flexible printed wiring board 3, and the voltage detection line 41 and the control unit 38 can be connected by one connector 43.

The assembled battery 60 can have a structure in which a plurality of such battery groups of the battery cells 2 and the flexible printed wiring board 3 are connected to each other. In this case, a plurality of battery groups can be arranged so that the flexible printed wiring board 3 is located between two adjacent battery groups. Further, the positive electrode extending portion 25 or the negative electrode extending portion 26 of the battery cell 2 included in one of the two adjacent battery groups and the positive electrode extending portion 25 or the negative electrode extending portion 26 of the battery cell 2 included in the other battery group. A plurality of battery groups can be arranged so as to face the protrusion 26. In this case, the two flexible printed wiring boards 3 arranged between two adjacent battery groups may be arranged facing each other. In this case, since the flying lead portions 6 are also arranged facing each other, the insulating partition wall 36 can be provided between the flexible printed wiring boards 3 facing each other. Thereby, even when the assembled battery 60 has a structure in which a plurality of battery groups are arranged side by side, all the battery cells 2 included in the assembled battery 60 can be connected by one bent flexible printed wiring board 3. As a result, the voltage detection line 41 can be provided on one flexible printed wiring board 3, and the voltage detection line 41 and the control unit 38 can be connected by one connector 43.

For example, in the case of the assembled battery 60 including the battery cells 2a to 2e shown in FIGS. 1 and 2, one bent flexible printed wiring board 3 is arranged along the first side surface and the second side surface of the battery group. The flexible printed wiring board 3 has 10 flying lead portions 6a to 6j corresponding to the positive electrode terminals 4a to 4e and the negative electrode terminals 5a to 5e on the first and second side surfaces. Further, the positive electrode terminals 4a to 4e or the negative electrode terminals 5a to 5e and the flying lead portions 6a to 6j are joined to form the joint portions 11a to 11j.
Further, for example, in the case of the assembled battery 60 including the battery cells 2a to 2l shown in FIGS. 7 (c) and 7 (d), one bent flexible printed wiring board 3 is laminated with the battery cells 2a and 2b. The battery cells 2a to 2l are arranged along the side surface of the first battery group, the side surface of the second battery group in which the battery cells 2c to 2g are stacked, and the side surface of the third battery group in which the battery cells 2h to 2l are stacked. Are connected in series or in parallel.

The method for manufacturing the assembled battery 60 includes a step of bending the flying lead portion 6 having a cantilever structure of the flexible printed wiring board 3, and one of the positive electrode terminal 4 and the negative electrode terminal 5 of the battery cell 2 and the flying lead portion 6. A step of overlapping and joining the batteries and a step of bending the battery cell 2 and bending back the flying lead portion 6 are included.

Here, a method of manufacturing the assembled battery 60 as shown in FIGS. 1 to 3 will be described.
First, the flexible printed wiring board 3 as shown in the developed view of FIG. 4 is prepared. The flying lead portion 6 included in the flexible printed wiring board 3 is bent as shown in FIGS. 5A and 5B. In the step of bending the flying lead portion 6, the flying lead portion 6 is bent to the side opposite to the battery cell 2 side of the flexible printed wiring board 3, as in the flexible printed wiring board 3 included in the assembled battery 60 of FIG. As a result, as shown in FIG. 5B, the opening 45 provided with the flying lead portion 6 becomes wider.

Next, a plurality of pouch-type battery cells 2a to 2e are stacked on the flexible printed wiring board 3, and the positive electrode terminal 4 and the negative electrode terminal 5 of the battery cell 2 are provided in the opening 45 as shown in FIGS. 5 (c) and 6 (6). The inserted and bent flying lead portion 6 and the positive electrode terminal 4 or the negative electrode terminal 5 are overlapped with each other.
Next, as shown in FIG. 5D, the overlapping flying lead portion 6 and the positive electrode terminal 4 or the negative electrode terminal 5 are combined with the head portion 54 of the joiner or welder (in the case of ultrasonic welding, the ultrasonic horn and the anvil). The flying lead portion 6 is welded to the positive electrode terminal 4 or the negative electrode terminal 5 to form a joint portion 11. As the joiner or welder, for example, an ultrasonic welder, a resistance welder, or the like can be used. Further, the flying lead portion 6 and the positive electrode terminal 4 or the negative electrode terminal 5 may be joined by laser welding or pressure welding. Further, they may be joined by soldering, brazing, caulking or the like. By bending the flying lead portion 6 in this way, the flying lead portion 6 and the positive electrode terminal 4 or the negative electrode terminal 5 can be easily overlapped with each other, and the joining work becomes easy. In this embodiment, it is possible to secure a space for sandwiching the stacked flying lead portion 6 and the positive electrode terminal 4 or the negative electrode terminal 5 by the head portion 54. Further, since the main surface of the flying lead portion 6 can be joined to the main surface of the positive electrode terminal 4 or the main surface of the negative electrode terminal 5, stronger bonding can be achieved.

Next, the plurality of battery cells 2a to 2e are bent so that the positive electrode bent portion 30 and the negative electrode bent portion 31 are formed, and the plurality of flying lead portions 6a to 6j are bent back as shown in FIG. 5 (e). At this time, the flexible printed wiring board 3 on the side surface of the battery group in which the plurality of battery cells 2a to 2e are laminated is pulled up. As a result, the assembled battery 60 as shown in FIG. 6 can be transformed into the assembled battery 60 as shown in FIGS. 1 to 3. This makes it possible to reduce the size of the assembled battery 60. After that, by connecting the connection terminals 42a and 42b of the flexible printed wiring board 3 and the connector 43 to the control unit 38, the assembled battery 60 as shown in FIGS. 1 and 2 can be manufactured.

Further, in the method of manufacturing the assembled battery 60 shown in FIG. 7, a plurality of pouch-type battery cells 2a to 2l are laminated on the flexible printed wiring board 3 as shown in FIG. 7A, and the flying lead portion is bent. 6 and the positive electrode terminal 4 or the negative electrode terminal 5 are overlapped with each other. After that, the flying lead portion 6 is joined to the positive electrode terminal 4 or the negative electrode terminal 5, the plurality of battery cells 2a to 2l are bent, and the plurality of flying lead portions 6 are bent back and the flexible printed wiring board 3 on the side surface of the battery group is pulled up. .. After that, the flexible printed wiring board 3 is bent along the dotted line D and the dotted line E in FIG. 7B so that the flexible printed wiring board 3 is located between two adjacent battery groups. This makes it possible to change the arrangement of the battery groups of the battery cells 2 as shown in FIG. 7 (c). Further, by forming the flexible printed wiring board 3 in a bent structure, the unfolded length of the flexible printed wiring board 3 can be shortened, and the manufacturing cost of the flexible printed wiring board 3 can be reduced.
Next, as shown in FIG. 7D, the flexible printed wiring board 3 and the battery cell 2 can be housed in the housing 35 to form the assembled battery 60. Further, the housing 35 can have partition walls 36a and 36b located between two adjacent battery groups.

In this embodiment, the plurality of battery cells 2 included in the battery group are stacked in the vertical direction, but can be stacked in a direction other than the vertical direction as long as the battery cells 2 are in the thickness direction.

2, 2a to 2l: Battery cell 3: Flexible printed wiring board 4: Positive electrode terminal 5: Negative electrode terminal 6, 6a to 6j: Flying lead part 7: Positive electrode 8: Negative electrode 9: Separator 10, 10a to 10e: Laminated structure 11, 11a to 11j: Joints 12, 12a to 12e: Electrode aggregate 15: Electrode 16, 16a, 16b: Exterior 18: Positive electrode current collector sheet 19: Positive electrode active material layer 22: Negative electrode current collector sheet 23: Negative electrode active material layer 25: Positive electrode extension 26: Negative electrode extension 30: Positive electrode bend 31: Negative electrode bend 35: Housing 36, 36a, 36b: Partition 37: Lid 38: Control unit 40: Power line 41: Voltage detection line (battery) State detection line) 42, 42a, 42b: Connection terminal 43: Connector 44: Insulation film 45, 45a to 45j: Opening 46: Positive electrode side clip 47: Negative electrode side clip 48: Base film 49: Cover film 51: Positive electrode side seal Stop 52: Negative electrode side sealing part 54: Joiner head part 60: Assembled battery

Claims (12)

Equipped with multiple battery cells and a flexible printed wiring board,
Each battery cell has a plate-shaped terminal that extends from the inside of the exterior to the outside.
The plurality of battery cells are connected in series or in parallel by the flexible printed wiring board.
The flexible printed wiring board has at least one layer or more of a laminated structure including an insulating base film.
The base film has an opening in a part and
The flexible printed wiring board is provided with a flying lead portion in the opening in which both surfaces of the metal layer are not covered with an insulating layer.
At least a part of the flying lead portion is connected to the laminated structure of the flexible printed wiring board.
An assembled battery characterized in that the terminals and the flying lead portion are joined to each other. The assembled battery according to claim 1 , wherein the flying lead portion has a cantilever structure in which one end is fixed to the laminated structure of the flexible printed wiring board and the other end can move . The assembled battery according to claim 1 or 2, wherein the opening is formed in a plane excluding the end portion of the flexible printed wiring board. The flexible printed wiring board has a power line and a battery state detection line.
The assembled battery according to any one of claims 1 to 3, wherein the flying lead portion is a part of the power line. The assembled battery according to claim 4, wherein the power line and the battery state detection line are connected inside the flexible printed wiring board. The assembled battery according to claim 4 or 5, wherein the power line is a metal plate having a thickness of 100 μm or more and 300 μm or less. Each battery cell has a flat plate shape and has a flat plate shape.
The assembled battery according to any one of claims 1 to 6, wherein the plurality of battery cells are stacked in the thickness direction of the battery cells. The battery cell includes an electrode assembly inside the exterior body.
The electrode assembly is formed by superimposing at least one positive electrode, at least one negative electrode, and at least one separator.
The terminal is a positive electrode terminal or a negative electrode terminal.
The battery cell is
A positive electrode extending portion in which a positive electrode current collecting sheet extends from the electrode aggregate, and a positive electrode extending portion.
With the positive electrode terminal joined to the positive electrode extending portion,
The negative electrode extending portion where the negative electrode current collecting sheet extends from the electrode assembly, and the negative electrode extending portion .
The negative electrode terminal provided with the negative electrode extending portion is provided.
Claim 1 in which the positive electrode extending portion, the negative electrode extending portion , the terminal, or the exterior body is bent between the end portion of the electrode assembly and the joint portion between the terminal and the flying lead portion. The assembled battery according to any one of 7 to 7. Equipped with multiple battery groups,
Each battery group has a structure in which a plurality of battery cells are stacked in the thickness direction.
A plurality of battery cells included in each battery group are connected in series or in parallel by the flexible printed wiring board.
The assembled battery according to any one of claims 1 to 8, wherein the plurality of battery groups are connected by the same flexible printed wiring board. The two adjacent battery groups are the flexible printed wiring board to which a plurality of battery cells included in the first battery group are connected, and the flexible printed wiring board to which the plurality of battery cells included in the second battery group are connected. It is arranged so as to face the second part of the printed wiring board.
The assembled battery according to claim 9, wherein an insulating partition wall is provided between the first portion and the second portion of the flexible printed wiring board. The process of bending the plate-shaped flying lead part, which is at least partly connected to the laminated structure of the flexible printed wiring board,
The process of overlapping and joining the plate-shaped terminal extending from the inside to the outside of the outer body of the battery cell and the flying lead portion.
A method for manufacturing an assembled battery, which comprises a step of bending back the flying lead portion. The method for manufacturing an assembled battery according to claim 11, wherein the step of bending back the flying lead portion is a step involving bending of the terminal or the exterior body.

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