Battery module

Abstract

The present disclosure relates to a battery module. A battery module in which a stacked body formed by stacking a plurality of battery cells are housed in a module case and the plurality of battery cells are electrically connected to each other via a bus bar, the battery cells being housed in a posture in which the stacking direction is the thickness direction, the battery module comprising: a first electrode lead wire that is electrically connected to the first electrode lead wire; a first side surface part along one side in the thickness direction protrudes towards one side in the width direction; and a second electrode lead protruding along a second side surface portion on the other side in the thickness direction toward the other side in the width direction. The battery cell forms a symmetrical structure in which the height positions of the first electrode lead and the second electrode lead are not changed in an inverted posture in which the first electrode lead and the second electrode lead are inverted along a center line in the thickness direction and in an inverted posture in which the second electrode lead and the second electrode lead are inverted along a center line in the width direction.

Description

Technical Field

[0001] The present disclosure relates to a battery module. Background Art

[0002] Japanese Patent Application Publication No. 2009-016122 describes a stacked secondary battery in which a battery element having a substantially rectangular planar shape is packaged with a laminate, wherein positive and negative electrodes are stacked with separators interposed therebetween, and positive and negative electrode tabs are led out from opposing sides.

[0003] In the stacked secondary battery, the positive electrode tab and the negative electrode tab are arranged to deviate from the center line of their respective lead-out edges. Thus, when multiple tabs are stacked, the upper and lower tabs that are electrically connected are arranged in the same direction relative to the center line to facilitate connection, and the upper and lower tabs that are not electrically connected are arranged in different directions relative to the center line to avoid contact.

[0004] However, in a module in which a plurality of secondary batteries (battery cells) are connected to each other via a bus bar, as in the above-mentioned Patent Document 1, when the electrode tabs are connected to each other at a plurality of positions within the module housing in consideration of the close arrangement or separated arrangement of adjacent electrode tabs, the bus bar arrangement may become complicated and large-scale, thereby reducing the space efficiency within the module housing. Summary of the invention

[0005] The present disclosure has been made in consideration of the above-mentioned facts, and an object thereof is to obtain a battery module capable of optimizing the arrangement of bus bars and improving the space efficiency within a module case.

[0006] The battery module of the first mode houses a stacked body formed by stacking a plurality of battery cells on each other in a module housing, wherein the plurality of battery cells are electrically connected to each other via bus bars, wherein the battery cells are housed with the stacking direction as the thickness direction, and the battery cells have: a first electrode lead, a first side portion along one side of the thickness direction protruding toward one side of the width direction; and a second electrode lead, a second side portion along the other side of the thickness direction protruding toward the other side of the width direction, the battery cell forming a symmetrical structure in which the height positions of the first electrode lead and the second electrode lead remain unchanged in an inverted posture along a center line of the thickness direction and an inverted posture along a center line of the width direction.

[0007] In the battery module of the first embodiment, a stacked body formed by stacking a plurality of battery cells is housed in a module housing. In addition, the plurality of battery cells are electrically connected to each other via bus bars. The battery cells are housed in a posture with the stacking direction as the thickness direction, and have a first electrode lead protruding from a first side portion along one side of the thickness direction to one side of the width direction and a second electrode lead protruding from a second side portion along the other side of the thickness direction to the other side of the width direction. That is, in each battery cell, the first electrode lead and the second lead are set at different positions in the stacking direction.

[0008] Here, the battery cell forms a symmetrical structure in which the height positions of the first electrode lead and the second electrode lead remain unchanged in an inverted posture along the center line in the thickness direction and an inverted posture along the center line in the width direction. Therefore, by storing a part of the battery cells in the module housing in an inverted posture along the center line in the thickness direction and the center line in the width direction, it is possible to achieve close arrangement of electrode leads with the same electrical polarity and close arrangement of electrode leads with different electrical polarities at the same height position in the module housing. As a result, the arrangement of the busbar can be optimized, and the space efficiency in the module housing can be improved.

[0009] The battery module of the second embodiment is based on the first embodiment, and the stacked body has at least one first stacked portion, which makes one of the two battery cells adjacent to each other in the stacking direction be inverted along the center line of the thickness direction, thereby arranging the first electrode lead and the second electrode lead close to each other on one side of the width direction.

[0010] In the battery module of the second embodiment, the stack has at least one first stack portion. In the first stack portion, one of two battery cells adjacent to each other in the stacking direction is placed in an inverted position along the center line in the thickness direction, so that the first electrode lead and the second electrode lead are arranged close to each other in one side in the width direction. Therefore, electrode leads with different electrical polarities can be arranged close to each other, and the series connection between the two battery cells can be easily and efficiently performed via the bus bar.

[0011] The battery module of the third mode is based on the first mode, and the stacked body has at least one second stacked portion, and the second stacked portion makes one of the two battery cells adjacent to each other in the stacking direction be inverted along the center line of the width direction, thereby arranging the first electrode leads or the second electrode leads close to each other on one side of the width direction.

[0012] In the battery module of the third embodiment, the stack has at least one second stack portion. In the second stack portion, one of two battery cells adjacent in the stacking direction is placed in an inverted position along the center line in the width direction, so that the first electrode lead and the second electrode lead are arranged close to each other in one side in the width direction. Therefore, electrode leads with the same electrical polarity can be arranged close to each other, and parallel connection between two battery cells can be easily and efficiently performed via a bus bar.

[0013] The battery module of the fourth embodiment is based on the second embodiment, wherein the stacked body has a plurality of third stacked sections formed by stacking two adjacent battery cells in the stacking direction in the same posture, and one of the two third stacked sections adjacent to each other in the stacking direction is in an inverted posture inverted along the center line of the thickness direction, so that the first stacked section is formed by two adjacent battery cells between the two third stacked sections, and the bus bar has at least one series connection section on one side in the width direction of the stacked body for electrically connecting the first electrode lead and the second electrode lead that are close to each other in the first stacked section in series.

[0014] In the battery module of the fourth embodiment, the stack has a plurality of third stacking parts formed by stacking two battery cells adjacent in the stacking direction in the same posture. In addition, in the stack, when two third stacking parts adjacent in the stacking direction are electrically connected in series, one of the two third stacking parts is made to be in an inverted posture inverted along the center line of the thickness direction, so that a first stacking part is formed between the two third stacking parts by two adjacent battery cells. Therefore, on the bus bar, on one side in the width direction of the stack, a series connection part is formed in which the first electrode lead and the second electrode lead close to the first stacking part are electrically connected in series. Thus, when the stacking parts composed of two battery cells connected in parallel are electrically connected in series, a plurality of leads can be efficiently arranged on one side in the width direction of the stack, and as a result, the series connection between the stacking parts composed of two battery cells connected in parallel can be easily and efficiently performed via the bus bar.

[0015] As described above, in the battery module of the present disclosure, the arrangement of the bus bars can be optimized, thereby improving the space efficiency in the module case. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Exemplary embodiments of the present invention will be described in detail based on the following drawings, in which:

[0017] Figure 1 is a schematic plan view showing a main part of a vehicle to which the battery pack according to the embodiment is applied;

[0018] Figure 2 is a schematic perspective view of a battery module according to an embodiment;

[0019] Figure 3 is a top view of the battery module according to the embodiment with an upper cover of the module housing removed;

[0020] Figure 4 is a schematic diagram of a battery cell housed in a battery module as viewed from the thickness direction;

[0021] Figure 5 This is a schematic diagram of a battery cell housed in a battery module as viewed from a height direction;

[0022] Fig. 6A This is a schematic diagram of the first stacked portion of the stacked body according to the embodiment as viewed from the height direction;

[0023] Figure 6B is a schematic diagram of the second laminated portion of the laminated body according to the embodiment as viewed from a height direction; and

[0024] Figure 6C This is a schematic diagram of a third stacked portion and a series connection portion that electrically connects two adjacent third connection portions in series in a stacked body according to an embodiment as viewed from a height direction. DETAILED DESCRIPTION

[0025] Below, refer to Figure 1 to Figure 6C , an embodiment of the present disclosure is described.

[0026] (Overall Structure of Vehicle 100)

[0027] Figure 1 1 is a schematic top view showing the main parts of a vehicle 100 to which the battery pack 10 according to the embodiment is applied. Figure 1 As shown, the vehicle 100 is an electric vehicle (BEV) having a battery pack 10 mounted under the floor. It should be noted that the arrows UP, FR, and LH in the respective figures indicate the upper side in the vehicle vertical direction, the front side in the vehicle front-rear direction, and the left side in the vehicle width direction, respectively. When the directions of front, back, left, right, up, and down are used for explanation, unless otherwise specified, they indicate the front and back in the vehicle front-rear direction, the left and right in the vehicle width direction, and the up and down in the vehicle vertical direction.

[0028] As an example, the vehicle 100 of the present embodiment has a DC / DC converter 102, an electric compressor 104, and a PTC (Positive Temperature Coefficient) heater 106 disposed on the front side of the vehicle relative to the battery pack 10. In addition, a motor 108, a gear box 110, an inverter 112, and a charger 114 are disposed on the rear side of the vehicle relative to the battery pack 10.

[0029] The DC current output from battery pack 10 is supplied to electric compressor 104, PTC heater 106, inverter 112, etc. after the voltage is adjusted by DC / DC converter 102. In addition, by supplying power to motor 108 via inverter 112, the rear wheels rotate and vehicle 100 travels.

[0030] A charging port 116 is provided on the right side of the rear portion of the vehicle 100 . By connecting a charging plug of an external charging device (not shown) to the charging port 116 , electric power can be stored in the battery pack 10 via the on-vehicle charger 114 .

[0031] It should be noted that the configuration and structure of the various components constituting the vehicle 100 are not limited to the above-mentioned structure. For example, it can also be applied to a hybrid vehicle (HV: Hybrid Vehicle) or a plug-in hybrid vehicle (PHEV: Plug-in Hybrid Electric Vehicle) equipped with an engine. In addition, in the present embodiment, the motor 108 is mounted on the rear of the vehicle and is a rear-wheel drive vehicle, but it is not limited to this. It can also be a front-wheel drive vehicle with the motor 108 mounted on the front of the vehicle, and a pair of motors 108 can also be mounted on the front and rear of the vehicle. In addition, it can also be a vehicle with a hub motor on each wheel.

[0032] Here, the battery pack 10 is configured to include a plurality of battery modules 11. In the present embodiment, as an example, 10 battery modules 11 are provided. Specifically, five battery modules 11 are arranged along the vehicle front-rear direction on the right side of the vehicle 100, and five battery modules 11 are arranged along the vehicle front-rear direction on the left side of the vehicle 100. In addition, each battery module 11 is electrically connected.

[0033] Figure 2 1 is a schematic three-dimensional diagram of the battery module 11. Figure 2 As shown, the battery module 11 includes a module housing 16 forming an outer shell. The module housing 16 is formed into a substantially rectangular parallelepiped shape with the vehicle width direction as the length direction. In addition, the module housing 16 is formed of an aluminum alloy. For example, an aluminum die casting is joined to both ends of an aluminum alloy extruded material by laser welding or the like, thereby forming the module housing 16.

[0034] A pair of voltage terminals 12 and a connector 14 are provided at both ends of the battery module 11 in the vehicle width direction. A flexible printed circuit board 21 described later is connected to the connector 14. In addition, bus bars 30 (see FIG. 1 ) are welded to both ends of the battery module 11 in the vehicle width direction. Figure 4 ).

[0035] The battery module 11 has a length MW in the vehicle width direction of, for example, 350 mm to 600 mm, a length ML in the vehicle front-rear direction of, for example, 150 mm to 250 mm, and a height MH in the vehicle vertical direction of, for example, 80 mm to 110 mm.

[0036] Figure 3 FIG. 1 is a top view of the battery module 11 with the upper cover removed. Figure 3 As shown, a stacked body 20P formed by stacking a plurality of battery cells 20 is stored inside the module housing 16. Each battery cell 20 is stored in a posture with the stacking direction as the thickness direction. In this embodiment, 24 battery cells 20 are arranged (stacked) in the front-rear direction of the vehicle and bonded to each other, thereby forming the stacked body 20P.

[0037] It should be noted that in order to facilitate the understanding of the description, Figure 3 to Figure 5 In each of the figures, the direction indicated by the arrow W is set as the width direction of the battery cell 20, the direction indicated by the arrow H is set as the height direction (vertical direction) of the battery cell 20, and the direction indicated by the arrow D is set as the thickness direction of the battery cell 20.

[0038] The width direction of the battery case 22 described below coincides with the width direction W of the battery cell 20 . The height direction of the battery case 22 coincides with the height direction H of the battery cell 20 . The thickness direction of the battery case 22 coincides with the thickness direction D of the battery cell 20 .

[0039] A flexible printed circuit (FPC) 21 is disposed on the battery cell 20. The flexible printed circuit 21 is formed in a strip shape with the vehicle width direction as the longitudinal direction, and thermistors 23 are provided at both ends of the flexible printed circuit 21. The thermistor 23 is a structure that is not bonded to the battery cell 20 and is pressed toward the battery cell 20 by the upper cover of the battery module 11.

[0040] In addition, one or more buffer materials (not shown) are stored inside the module case 16. For example, the buffer material is a thin plate-shaped member that can be elastically deformed, and is arranged between the battery cells 20 adjacent to each other in the thickness direction of the arrangement direction of the battery cells 20. In this embodiment, as an example, the buffer materials are arranged at both ends in the longitudinal direction and the central part in the longitudinal direction of the module case 16.

[0041] Figure 4 2 is a schematic diagram of a battery cell 20 housed in a battery module 11 as viewed from the thickness direction D. Figure 4 As shown, the battery cell 20 is formed in a rectangular plate shape with the width direction W as the longitudinal direction, and includes an exterior member 21 forming an outer shell and an electrode body 40 accommodated in the interior of the exterior member 21 .

[0042] Figure 5 2 is a schematic diagram of the battery unit 20 stored in the battery module 11 as viewed from the height direction H. Figure 5 As shown, the exterior member 21 includes a first side surface portion 21A constituting one side surface in the thickness direction D of the battery cell 20 and a second side surface portion 21B constituting the other side surface in the thickness direction D.

[0043] Various exterior components can be applied as the exterior component 21. For example, the exterior component 21 may also be composed of a laminate film, a flat box-shaped housing, or the like. In addition, the exterior component 21 may also be composed of a coating material applied directly or via a coating material such as a film to the electrode body 40. In the present embodiment, the battery housing 22 is formed by bonding a plurality of laminate films, and the electrode body 40 is sealed by the laminate film.

[0044] The electrode body 40 is composed of a stacked positive electrode, a stacked negative electrode, and a separator. The positive electrode and the negative electrode of the electrode body 40 are made of metal foil or the like. The ends of the stacked positive electrode sheets are gathered together on one side of the width direction W of the electrode body 40 to form a positive electrode current collector 41, which is connected to the electrode lead 26 (26A) described later (see Figure 5 ). In addition, on the other side of the width direction W of the electrode body 40, the ends of the stacked multiple negative electrode sheets are gathered together to form a negative electrode collector 42, which is connected to the electrode lead 26 (26B) (see Figure 5 ).

[0045] The electrode lead 26 is provided so as to protrude from both ends of the battery cell 20 (exterior member 21) in the width direction W. The electrode lead 26 is formed in a thin plate shape, and one end disposed inside the battery case 22 is connected to the electrode body 40. The electrode lead 26 is composed of a first electrode lead 26A connected to the positive electrode collector 41 of the electrode body 40 and a second electrode lead 26B connected to the negative electrode collector 42 of the electrode body 40. The first electrode lead 26A protrudes toward one side in the width direction W along the first side surface 21A on one side in the thickness direction D of the battery cell 20. The second electrode lead 26B protrudes toward the other side in the width direction W along the second side surface 21B on the other side in the thickness direction D. Therefore, when the battery cell 20 is viewed from above in the height direction H, the positions of the first electrode lead 26A and the second electrode lead 26B are disposed at different positions in the thickness direction D (stacking direction).

[0046] In addition, the first electrode lead 26A and the second electrode lead 26B protrude from the center position of the height direction H of the battery cell 20 (see Figure 4 Therefore, the battery cell 20 is formed such that the height positions of the first electrode lead 26A and the second electrode lead 26B are on the center line C1 along the thickness direction D (see Figure 5) A symmetrical structure that remains unchanged in the inverted posture when the body is inverted and the inverted posture when the body is inverted along the center line C2 in the width direction W.

[0047] The electrode lead 26 of each battery cell is welded to a bus bar 30 described later, thereby electrically joining the battery cells 20 to each other via the bus bar 30. In addition, the electrode lead 26 is connected to the wiring outside the battery module 11 via the bus bar 30. The electrode lead 26 and the bus bar 30 can be welded by a known welding method as appropriate, but in this embodiment, the electrode lead 26 and the bus bar 30 are joined by laser welding.

[0048] The length CW1 of the battery cell 20 in the vehicle width direction is, for example, 530 mm to 600 mm, 600 mm to 700 mm, 700 mm to 800 mm, 800 mm to 900 mm, or 1000 mm or more, the length CW2 of the region where the electrode body is stored is, for example, 500 mm to 520 mm, 600 mm to 700 mm, 700 mm to 800 mm, 800 mm to 900 mm, or 1000 mm or more, and the height CH of the battery cell 20 is, for example, 80 mm to 110 mm, 110 mm to 140 mm. In addition, the thickness of the battery cell 20 is 5.0 mm to 7.0 mm, 7.0 mm to 9.0 mm, or 9.0 mm to 11.0 mm, and the height TH of the electrode lead (terminal) 26 is 40 mm to 50 mm, 50 mm to 60 mm, or 60 mm to 70 mm.

[0049] The bus bar 30 is formed in a plate shape with the width direction W of the battery cell 20 as the plate thickness direction, and extends along the stacking direction (thickness direction D) of the battery cell 20. In the module case 16, a plurality of bus bars 30 are arranged on one side and the other side of the width direction W of the battery cell 20. As an example, the electrode lead 26 is inserted into a groove-shaped through hole 32 that penetrates the bus bar 30 in the plate thickness direction, and is welded to the surface of the bus bar 30 in a state where the end protruding from the through hole 32 is folded back to the bus bar 30 side. As a result, welding can be performed by working from the outside of the width direction W of the battery cell 20, and construction becomes easy.

[0050] The bus bar 30 is provided with a first connection portion 30A (see Figure 6B ) and the second connecting portion 30B (see Fig. 6A ), the first connection portion 30A electrically connects adjacent battery cells in parallel, and the second connection portion 30B electrically connects the two first connection portions 30A in series.

[0051] (About the stacking method of battery cells)

[0052] As described above, the battery cell 20 is formed such that the height positions of the first electrode lead 26A and the second electrode lead 26B are aligned with the center line C1 along the thickness direction D (see Figure 5 ) and the inverted posture along the center line C2 in the width direction W. With such a symmetrical structure of the battery cells 20, the battery module 11 accommodates a portion of the battery cells 20 in the module case 16 in a posture inverted along the center line C1 in the thickness direction D and the center line C2 in the width direction W, thereby enabling the electrode leads 26 with the same electrical polarity to be arranged close to each other, the electrode leads 26 with different electrical polarities to be arranged close to each other, etc. at the same height position in the module case 16.

[0053] Reference Figure 6A to Figure 6C , an example of a stacking method of the battery cells 20 is described. Figure 6A to Figure 6C The schematic diagram shows a first stacked portion 20P1 , a second stacked portion 20P2 , and a third stacked portion 20P3 that can constitute a part or all of the stacked body 20P, assuming that the stacked body 20P in the module case 16 is viewed from above.

[0054] It should be noted that in Figure 6A to Figure 6C In the figure, for the sake of convenience, a state in which a gap is set between adjacent battery cells 20 is illustrated, but in fact, the stacked multiple battery cells 20 are constrained to each other via buffer materials or direct contact in a state in which a predetermined constraining pressure is applied along the stacking direction (thickness direction D).

[0055] exist Fig. 6A The first stacking section 20P1 that can constitute a part or all of the stacking body 20P is shown. The first stacking section 20P1 is stacked so that one of the two battery cells 20 adjacent to each other in the stacking direction is inverted along the center line C1 in the thickness direction D. In the first stacking section 20P1, by inverting one battery cell 20, the first electrode lead 26A and the second electrode lead 26B are arranged close to each other on one side in the width direction W. That is, on one side in the width direction W of the first stacking section 20P1, the electrode leads 26 with different electrical polarities can be led out to the bus bar 30 side in a state of being arranged close to each other. Fig. 6A In the illustrated example, adjacent battery cells 20 are connected in series via the second connection portion 30B of the bus bar 30 .

[0056] exist Figure 6B2 shows a second stacking section 20P2 that can constitute a part or all of the stacking body 20P. The second stacking section 20P2 is stacked in an inverted posture in which one of two battery cells 20 adjacent in the stacking direction is inverted along the center line C2 in the width direction W. In the second stacking section 20P2, on one side in the width direction W, the first electrode leads 26A (or the second electrode leads 26B) having the same electrical polarity can be led out to the bus bar 30 side in a state of being arranged close to each other. Figure 6B In the illustrated example, adjacent battery cells 20 are connected in parallel via first connection portions 30A of bus bars 30 .

[0057] exist Figure 6C 2 shows a third stacked portion 20P3 that can constitute a part or all of the stacked body 20P. The third stacked portion 20P3 stacks two adjacent battery cells in the stacking direction in the same posture. In the third stacked portion 20P3, the first electrode leads 26A and the second electrode leads 26B having the same electrical polarity are separated and arranged on one side and the other side in the width direction W according to the thickness of the battery cell 20.

[0058] In addition, Figure 6C In the example shown, two third laminated parts 20P3 are adjacent to each other in the stacking direction, and one of the two third laminated parts 20P3 is stacked in an inverted posture along the center line C1 in the thickness direction D. Therefore, between the two third laminated parts 20P3, the first laminated part 20P1 is formed by two adjacent battery cells 20. That is, on one side in the width direction W of the laminated body 20P, the first electrode lead 26A of the battery cell 20 constituting one of the two third laminated parts 20P3 and the second electrode lead 26B of the battery cell 20 constituting the other of the two third laminated parts 20P3 can be led out to the bus bar 30 side in a state of being arranged close to each other.

[0059] In the bus bar 30, the two battery cells 20 constituting the third stacked portion 20P3 are connected in parallel via the first connection portion 30A. In addition, in the bus bar 30, the two third stacked portions 20P3 are connected in series via the second connection portion 30B. In this way, the bus bar 30 is formed with a series connection portion 30C that electrically connects the stacked portions consisting of the two battery cells 20 connected in parallel in series.

[0060] (Function and effect)

[0061] As described above, in the battery module 11 of the present embodiment, a stacked body 20P formed by stacking a plurality of battery cells 20 is housed in the module housing 16. In addition, the plurality of battery cells 20 are electrically connected to each other via the bus bar 30. The battery cell 20 is housed in a posture with the stacking direction being the thickness direction D, and has a first electrode lead 26A protruding from a first side portion 21A along one side of the thickness direction D to one side of the width direction W. In addition, the battery cell 20 has a second side portion 21B along the other side of the thickness direction D protruding from the other side of the width direction W to the second electrode lead 26B. That is, in each battery cell 20, the first electrode lead 26A and the second electrode lead 26B are set at different positions in the stacking direction.

[0062] Here, the battery cell 20 has a symmetrical structure in which the height positions of the first electrode lead 26A and the second electrode lead 26B remain unchanged in an inverted posture along the center line C1 in the thickness direction D and an inverted posture along the center line C2 in the width direction W. Therefore, by housing a portion of the battery cells 20 in the module case 16 in an inverted posture along the center line C1 in the thickness direction D and the center line C2 in the width direction W, it is possible to achieve close arrangement of the electrode leads 26 with the same electrical polarity and close arrangement of the electrode leads 26 with different electrical polarities at the same height position in the module case 16. As a result, the arrangement of the bus bar 30 can be optimized, and the space efficiency in the module case 16 can be improved.

[0063] In addition, if Fig. 6A As shown, the stacked body 20P of the present embodiment may also be partially or entirely composed of the first stacked portion 20P1. In the first stacked portion 20P1, one of the two battery cells 20 adjacent to each other in the stacking direction is inverted along the center line C1 in the thickness direction D, so that the first electrode lead 26A and the second electrode lead 26B are arranged close to each other in one side of the width direction W. Therefore, the electrode leads 26 with different electrical polarities can be arranged close to each other, and the series connection between the two battery cells 20 can be easily and efficiently performed via the bus bar 30.

[0064] In addition, if Figure 6B As shown, the stacked body 20P of the present embodiment may also be partially or entirely composed of the second stacked portion 20P2. In the second stacked portion 20P2, one of the two battery cells 20 adjacent in the stacking direction is made to be inverted along the center line C2 in the width direction W, so that the first electrode lead 26A and the second electrode lead 26B are arranged close to each other on one side in the width direction W. Therefore, the electrode leads 26 with the same electrical polarity can be arranged close to each other, and the parallel connection between the two battery cells 20 can be easily and efficiently performed via the bus bar 30.

[0065] In addition, if Figure 6C As shown, the stacked body 20P of this embodiment may also be partially or entirely composed of a third stacked portion 20P3. In the third stacked portion 20P3, two battery cells 20 adjacent to each other in the stacking direction are stacked in the same posture, thereby enabling the electrode leads 26 with the same electrical polarity to be arranged separately from each other on one side and the other side of the width direction W.

[0066] Furthermore, in the stack 20P, when two third stacks 20P3 adjacent to each other in the stacking direction are electrically connected in series, one of the two third stacks 20P3 is in an inverted position inverted along the center line C1 in the thickness direction D, thereby forming a first stack 20P1 between the two third stacks 20P3 by two adjacent battery cells 20. Therefore, the bus bar 30 is formed with a series connection portion 30C, which electrically connects the first electrode lead 26A and the second electrode lead 26B adjacent to each other in the first stack 20P1 in series on one side in the width direction W of the stack 20P. Thus, when the stacks composed of two battery cells 20 connected in parallel are electrically connected in series, a plurality of electrode leads 26 can be efficiently arranged on one side in the width direction W of the stack 20P, and as a result, the series connection between the stacks composed of two battery cells 20 connected in parallel can be easily and efficiently performed via the bus bar 30.

Claims

1. A battery module, wherein a stacked body composed of a plurality of battery cells stacked on each other is housed in a module housing, wherein the plurality of battery cells are electrically connected to each other via a bus bar, wherein: The battery cells are stored in a posture with the stacking direction being the thickness direction. The battery unit has: a first electrode lead having a first side surface portion along one side in the thickness direction protruding toward one side in the width direction; and The second electrode lead protrudes toward the other direction in the width direction along the second side surface portion in the other direction in the thickness direction, The battery cell has a symmetrical structure in which the height positions of the first electrode lead and the second electrode lead do not change in an inverted posture along the center line in the thickness direction and in an inverted posture along the center line in the width direction.

2. The battery module according to claim 1, wherein: The stacked body has at least one first stacked portion that arranges the first electrode lead and the second electrode lead close to each other in one direction of the width by placing one of the two battery cells adjacent in the stacking direction in an inverted position along a center line in the thickness direction.

3. The battery module according to claim 1, wherein: The stacked body has at least one second stacked portion, which makes one of the two battery cells adjacent in the stacking direction be inverted along the center line of the width direction, thereby arranging the first electrode lead or the second electrode lead close to each other on one side of the width direction.

4. The battery module according to claim 2, wherein: The stacked body includes a plurality of third stacked portions formed by stacking two of the battery cells adjacent to each other in a stacking direction in the same posture. One of the two third stacking sections adjacent to each other in the stacking direction is inverted along the center line in the thickness direction, so that the first stacking section is formed by two adjacent battery cells between the two third stacking sections. The bus bar has at least one series connection portion that electrically connects the first electrode lead and the second electrode lead that are adjacent to each other in series in the first stacked portion, on one side in the width direction of the stacked body.

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