Battery pack and method for producing a battery pack

Abstract

A battery pack (30) includes a left holder (31L). The left holder (31L) includes a resin portion (32) molded from resin and a plurality of lead plates (41) held by the resin portion (32). The plurality of lead plates (41) includes a first lead plate (41) connected to a terminal (33a) of a first battery cell (33) and a second lead plate (41) connected to a terminal (33a) of another battery cell (33). A through-hole (32b) is formed in the resin portion (32) and penetrates the resin portion (32) in a left-right direction. The through-hole (32b) is located between the outer edges (41e) of the two lead plates (41). Due to the structure, a manufacturing process can be simplified.

Description

Background of the inventionField of the invention

[0001] The present disclosure relates to a battery pack and a manufacturing method for the battery pack. Description of the state of the art

[0002] A battery pack containing a plurality of battery cells is installed in electric vehicles (including four-wheeled electric vehicles, two-wheeled electric vehicles, and electric-assisted bicycles). For example, JP 2015-053205 A and WO 2013 / 077205 A1 disclose a battery pack with a plurality of battery cells having a cylindrical shape. The battery pack includes a plurality of conductive plates for connecting terminals of the plurality of battery cells.

[0003] In the manufacturing process of a battery pack, the positions of a plurality of conductive plates are generally aligned with the positions of a plurality of battery cells, and the terminals of the battery cells are welded to the conductive plates. However, in this case, the positions of the battery cells may not align with the positions of the conductive plates, and welding cannot be performed smoothly. Especially as the number of battery cells and the number of conductive plates increases, the alignment of the battery cells and the conductive plates becomes complicated. Summary of the invention (1) A battery pack according to the present disclosure includes, for example: a plurality of battery cells each having a terminal at one end on a first side in a first direction; and a first holder arranged on the first side of the plurality of battery cells, the first holder having a resin portion molded from resin and a plurality of lead plates held by the resin portion. The plurality of battery cells includes a first battery cell and a second battery cell aligned in a second direction intersecting with the first direction.The plurality of conductive plates includes a first conductive plate having a first edge and a second conductive plate having a second edge facing the first edge in the second direction, the first conductive plate being connected to the terminal of the first battery cell and the second conductive plate being connected to the terminal of the second battery cell. A first through-hole penetrating the resin portion in the first direction is formed in the resin portion. The first through-hole is located between the first edge of the first conductive plate and the second edge of the second conductive plate.

[0004] According to the battery pack, the manufacturing process thereof can be simplified. For example, a method may be adopted in which the first holder is formed by insert molding using a base component including a plurality of lead plates connected to each other, and then the connected lead plates are separated with a punch inserted into the through hole. In this way, it is possible to reduce the amount of pressing processes required to obtain the plurality of lead plates and the number of parts required for the pressing processes. When a position of the first holder is aligned with a position of the battery cell, the positions of the plurality of lead plates coincide with the positions of the battery cells. This can facilitate a welding process of the lead plate and the battery cell. (2) In the battery pack according to (1), the first edge of the first conductive plate and the second edge of the second conductive plate may each have a portion exposed within the first through-hole. (3) In the battery pack according to (1) or (2), the plurality of battery cells may further include a third battery cell. The first battery cell, the second battery cell, and the third battery cell may each be arranged at the vertices of an equilateral triangle when the plurality of battery cells are viewed in the first direction. The first through-hole may be located in the center of the equilateral triangle when the plurality of battery cells are viewed in the first direction. According to the structure, a sufficient distance between the first through-hole and the battery cell is easily ensured. (4) In the battery pack according to (1) or (2), the plurality of battery cells may further include a third battery cell and a fourth battery cell. The first battery cell, the second battery cell, the third battery cell, and the fourth battery cell may each be arranged at the vertices of a square when the plurality of battery cells are viewed in the first direction. The first through-hole may be located in the center of the square when the plurality of battery cells are viewed in the first direction. According to the structure, a sufficient distance between the first through-hole and the battery cell is easily ensured. (5) In the battery pack according to any one of (1) to (4), the first holder may include a signal line electrically connected to a conductive plate and a third conductive plate. The signal line may be arranged along a third edge of the third conductive plate. A second through-hole may be formed in the resin portion, penetrating the resin portion in the first direction, the second through-hole being located between the signal line and the third edge of the third conductive plate.

[0005] According to the structure, it is possible to enable a manufacturing method in which the first holder is formed by insert molding using a base component including the signal line and the conductive plate connected to each other, and then the conductive plate and the signal line are separated with a punch inserted into the second through-hole. Accordingly, when the position of the first holder is aligned with the position of the battery cell, the position of the signal line can be optimized, thereby allowing the battery pack to be easily assembled. (6) In the battery pack according to (5), the signal line and the third edge of the third conductive plate may each have a portion exposed within the second through-hole. (7) In the battery pack according to any one of (1) to (6), a recess may be formed in the first edge of the first conductive plate, and an inner edge of the recess formed in the first edge may be exposed within the first through-hole. This structure makes it possible to shorten the distance between the edges of two adjacent conductive plates. As a result, the area of ​​each of the conductive plates can be increased, and the electrical resistance of each of the conductive plates can be reduced. (8) In the battery pack according to (7), a recess may be formed in the second edge of the second conductive plate, and an inner edge of the recess formed in the second edge may be exposed within the first through-hole. This structure makes it possible to further shorten the distance between the edges of two adjacent conductive plates. (9) In the battery pack according to any one of (1) to (6), the first edge of the first conductive plate may have a protrusion extending toward the second edge of the second conductive plate. The protrusion may be exposed within the first through-hole. (10) In the battery pack according to (9), a recess may be formed in the second edge of the second conductive plate, and the first through-hole may be located between the first edge of the first conductive plate and an inner edge of the recess formed in the second edge. Due to the structure, it is possible to shorten the distance between the edge of the first conductive plate and the edge of the second conductive plate. As a result, the area of ​​each of the conductive plates can be increased, and the electrical resistance of each of the conductive plates can be reduced. (11) In the battery pack according to any one of (1) to (10), the plurality of battery cells may each have a terminal at one end on a second side in the first direction. The battery pack may include a second holder arranged on the second side of the plurality of battery cells, the second holder including a resin portion molded from resin and a plurality of lead plates held by the resin portion. The plurality of battery cells may include a fifth battery cell and a sixth battery cell. The plurality of lead plates of the second holder may include a fourth lead plate and a fifth lead plate. A third through-hole penetrating the resin portion in the first direction may be formed in the resin portion of the second holder, and the third through-hole may be located between an edge of the fourth lead plate and an edge of the fifth lead plate. (12) A manufacturing method for a battery pack according to the present disclosure includes, for example: a process of manufacturing a base component including a first lead plate, a second lead plate aligned with the first lead plate, and a first connecting portion connecting an edge of the first lead plate and an edge of the second lead plate; a molding process of forming a holder including a resin portion that holds the base component by insert molding, and forming a first through-hole at a position corresponding to the first connecting portion in the resin portion; and a cutting process of cutting the connecting portion with a punch inserted into the first through-hole.

[0006] This manufacturing process makes it possible to reduce the amount of pressing work required to obtain the plurality of conductive plates and the number of parts required for the pressing work. When a position of the holder is aligned with a position of the battery cell, the positions of the plurality of conductive plates coincide with the positions of the battery cells. This simplifies the welding process of the conductive plate and the battery cell. (13) The manufacturing method according to (12) may further comprise: a process of manufacturing a plurality of battery cells including a first battery cell and a second battery cell, the plurality of battery cells each including a terminal at one end on a first side in a first direction; and a process of arranging the holder on the first side of the plurality of battery cells, welding the terminal of the first battery cell to the first conductive plate, and welding the terminal of the second battery cell to the second conductive plate. (14) In the manufacturing method according to (13), the plurality of battery cells may further include a third battery cell. The first battery cell, the second battery cell, and the third battery cell may each be arranged at the vertices of an equilateral triangle when the plurality of battery cells are viewed in the first direction, and the first through-hole is formed in the center of the equilateral triangle. According to the manufacturing method, a sufficient distance between the first through-hole and the battery cell is easily ensured. (15) In the manufacturing method according to (13), the plurality of battery cells may further include a third battery cell and a fourth battery cell. The first battery cell, the second battery cell, the third battery cell, and the fourth battery cell may each be arranged at the corners of a square when the plurality of battery cells are viewed in the first direction. The first through-hole is formed in the center of the square. The manufacturing method easily ensures a sufficient distance between the first through-hole and the battery cell. (16) In the manufacturing method according to any one of (12) to (15), the base component may include a third conductive plate, a signal line arranged along an edge of the third conductive plate, and a second connecting portion connecting the edge of the third conductive plate and the signal line. The molding process may include forming the second through-hole penetrating the resin portion at a position corresponding to the second connecting portion, and the cutting process may include cutting the second connecting portion with a punch inserted into the second through-hole. According to the method, the position of the signal line can be optimized when the position of the holder is aligned with the position of the battery cell, thereby making it easy to assemble the battery pack. Brief description of the drawings Fig. 1 is a side view of an electric bicycle having a battery pack according to the present disclosure mounted thereon; Fig. 2 is a perspective view showing an example of a battery pack; Fig. 3 is an exploded perspective view of the battery pack; Fig. 4A is a perspective view of a left holder in the battery pack; Fig. 4B is a perspective view showing the inside of the left holder (a battery cell side); Fig. 5 is an exploded perspective view showing a guide plate of the left holder, a battery cell, and a guide plate of a right holder; Fig. 6 is a view showing a positional relationship between a battery cell, a through hole formed in a resin portion, and a welding portion; Fig. 7A and Fig. 7B are views illustrating an electrical connection between the circuit board of the left holder, the battery cell, and the circuit board of the right holder; Fig. 8 is a flowchart illustrating a manufacturing method for the battery pack; Fig. 9A is a view showing an example of a basic component used in a manufacturing process of the battery pack, wherein two adjacent conductive plates are connected to each other and the two adjacent conductive plates are also connected to a signal line; Fig. 9B is a view showing a state in which the Fig. 9A shown circuit board and the signal line are separated; Fig. 10A is an enlarged view of a Fig. 9A shown area X; Fig. 10B is an enlarged view of a Fig. 9B, where the area X is in Fig. 9B with area X in Fig. 9A is identical; Fig. 11A is an enlarged view of a Fig. 9A shown area XI; Fig. 11B is an enlarged view of a Fig. 9B, where the area XI is in Fig. 9B with area XI in Fig. 9A is identical; Fig. 12A is an enlarged view of the Fig. 9A shown area XII; Fig. 12B is an enlarged view of a Fig. 9B, where the area XII is in Fig. 9B with area XII in Fig. 9A is identical; Fig. 13A to 13C are views for illustrating a method of cutting a connecting portion and are cross-sectional views of the left holder taken along a line XIII-XIII in Fig. 10A; and Fig. 14 is a view showing a modified example of a layout of the battery cell. Description of the embodiments

[0007] The present disclosure is to be considered as an exemplary illustration of the invention and is not intended to limit the invention to the specific embodiments shown in the figures or the following description. The present invention will now be described with reference to the accompanying figures, which illustrate exemplary embodiments.

[0008] The terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the invention. As used herein, the term "and / or" encompasses all combinations of one or more of the recited elements. The singular forms "a," "an," and "the" as used herein include both the plural and singular forms unless the context clearly indicates otherwise. It is further to be understood that the terms "comprises," "comprising," "includes," and / or "including," when used in this specification, specify the presence of the recited features, steps, operations, elements, and / or components, but do not preclude the presence or addition of one or more other features, steps, operations, elements, components, and / or groups thereof.

[0009] Unless otherwise defined, all terms used herein (including technical and scientific terms) have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs. It is further understood that terms as defined in commonly used dictionaries should be interpreted to have a meaning consistent with their meaning in the context of the relevant prior art and the present disclosure, and should not be interpreted in an idealized or overly formal sense unless expressly defined herein.

[0010] In describing the invention, it will be apparent that several technologies are disclosed. Each of them has individual advantages, and each may also be used in conjunction with one or more, or in some cases, all, of the other disclosed technologies. Accordingly, for the sake of clarity, this description refrains from unnecessarily repeating every possible combination of the individual technologies. Nevertheless, the description and claims should be read with the understanding that such combinations are fully within the scope of the invention and the claims.

[0011] In the following description, for purposes of explanation, numerous specific details are set forth in order to provide a thorough understanding of the present invention. However, it will be apparent to one skilled in the art that the present invention may be practiced without these specific details.

[0012] A battery pack and a manufacturing method for the battery pack according to the present disclosure will be described below. Fig. 1 is a side view of an electric-assisted bicycle 100, which is an example of a vehicle with a battery pack according to the present disclosure. The battery pack according to the present disclosure can be mounted on an electric vehicle (a vehicle that travels only by the driving power of an electric motor, such as a two-wheeled electric vehicle, a three-wheeled electric vehicle, or a four-wheeled electric vehicle).

[0013] As in Fig. As shown in Figure 1, the bicycle 100 includes a crankshaft 2. A crank arm is attached to one end of the crankshaft 2. A pedal 2a is connected to one end of the crank arm. The crankshaft 2 is mounted on a lower end of a seat tube 11. A saddle 18 is attached to an upper end of the seat tube 11.

[0014] The bicycle 100 includes at its front a handlebar stem 8, a handlebar 7 fixed to an upper portion of the handlebar stem 8, a front fork 19 fixed to a lower portion of the handlebar stem 8, and a front wheel 9 supported at a lower end of the front fork 19. The handlebar stem 8 is supported by a head tube 17a provided at a front end of a frame 17. The shape of the frame 17 is not limited to the Fig. 1 example and can be modified accordingly.

[0015] As in Fig. 1, the bicycle 100 includes a drive unit 20. The drive unit 20 includes an electric motor that outputs power to assist the driving of a rear wheel 6 (assist torque), and a reduction gear. The electric motor is powered by electrical energy from a battery pack 30. In the example of the bicycle 100, the battery pack 30 is attached to a rear side of the seat tube 11, and the drive unit 20 is arranged at a rear side of the crankshaft 2. The arrangement of the drive unit 20 and the battery pack 30 is not limited to the example of the bicycle 100 and can be changed as appropriate.

[0016] The force applied to the crankshaft 2 via the pedal 2a is transmitted to the rear wheel 6 via a chain 5. The power output from the drive unit 20 (torque of the electric motor) is also transmitted to the rear wheel 6 via the chain 5. Battery pack

[0017] Fig. 2 to 8 are views showing the battery pack 30, which is an example of a battery pack according to the present disclosure. In the drawings, the directions denoted by Z1 and Z2 are referred to as the upward direction and the downward direction, respectively. In the drawings, the directions denoted by X1 and X2 are referred to as the right direction and the left direction, respectively, and the directions denoted by Y1 and Y2 are referred to as the front direction and the rear direction, respectively. The directions are used to describe relative positions and shapes of parts, elements, and components constituting the battery pack 30 and do not limit the position of the battery pack 30 in the vehicle. Therefore, the battery pack 30 can be mounted on the bicycle 100, for example, such that the Fig. 2 is directed upwards in the rear direction (Y2 direction) of the bicycle 100.

[0018] As in Fig. 3, the battery pack 30 includes a plurality of battery cells 33, a left holder 31L, and a right holder 31R. The battery pack 30 may include a center holder 34 and a circuit board 51. The battery pack 30 may include a housing (not shown) that houses the battery cells 33 and the holders 31L and 31R. Battery cell

[0019] As in Fig. 3, the battery cell 33 includes a terminal 33a at one of its ends in the left-right direction. A portion of the battery cells 33 is arranged so that a positive terminal 33a+ faces a left side and a negative terminal 33a- faces a right side. The remaining battery cells 33 are arranged so that the positive terminal 33a+ faces the right side and the negative terminal 33a- faces the left side. Each of the battery cells 33 may be cylindrical. The majority of the battery cells 33 are aligned in two directions orthogonal to the left-right direction. Specifically, the majority of the battery cells 33 are aligned in the front-back direction (Y1-Y2 direction) and in an oblique direction inclined to the front-back direction and the up-down direction (Z1-Z2 direction). Central holder

[0020] As in Fig. 3, a plurality of holding holes 34a penetrating the central holder 34 in the left-right direction are formed in the central holder 34. Each of the plurality of battery cells 33 can be inserted into and held in the plurality of holding holes 34a. Unlike the example shown in the drawing, the battery pack 30 does not need to include the central holder 34. Then, the battery cell 33 can be held only by the left holder 31L and the right holder 31R, which will be described later. Left holder

[0021] The left holder 31L is arranged on the left side of the plurality of battery cells 33. The left holder 31L contains, as shown in the Fig. shown, a resin portion 32 and a plurality of guide plates 41A to 41F.

[0022] Each of the guide plates 41A to 41F includes a plurality of welding portions 41a. As shown in Fig. 5, for example, each of the conductive plates 41A and 41F may include three welding sections 41a, and each of the conductive plates 41B to 41E may include six welding sections 41a. Each of the welding sections 41a is welded to the left terminal 33a of the battery cell 33. A slot 41b (see Fig. 6) is formed, and an inner edge of the slot 41b can be welded to the terminal 33a. As shown in Fig. 6, the slot 41b has substantially an H-shape rotated by 90 degrees, for example, but the shape is not limited thereto and may be, for example, an I-shape.

[0023] As in Fig. As shown in FIG. 4B, a plurality of recesses 32a may be formed on a right surface (a surface facing the battery cell 33) of the resin portion 32. Each of the left portions of the plurality of battery cells 33 may be fitted into the plurality of recesses 32a.

[0024] The resin portion 32 and the conductive plates 41A to 41F are manufactured by injection molding. The conductive plates 41A to 41F are held by the resin portion 32. In particular, portions other than the welded portions 41a in the conductive plates 41A to 41F are embedded in a material of the resin portion 32.

[0025] In insert molding, the guide plates 41A to 41F (a base component 40L, described below) are placed in a mold cavity, and then the cavity is filled with molten resin (the material of the resin portion 32). Examples of the material of the resin portion 32 include polycarbonate (PC), acrylonitrile butadiene styrene (ABS) resin, PC and ABS mixed resin, polypropylene (PP), polyamide (PA), or polyphenylene sulfide (PPS). When the molten resin solidifies, the resin portion 32 is formed, and the guide plates 41A to 41F are fixed to the resin portion 32. The guide plates 41A to 41F can be fixed to the resin portion 32 without using fasteners such as screws and bolts.

[0026] As in Fig. 7A, the majority of the conductive plates 41A to 41F are arranged along a common plane and do not overlap when viewed in the left-right direction. For example, the left holder 31L includes the six conductive plates 41A to 41F. In one example of the battery pack 30, the conductive plate 41A is arranged at a front end. The conductive plate 41B is located behind a lower portion of the conductive plate 41A, and a front portion of the conductive plate 41C is located above the conductive plate 41B. The conductive plate 41D is located below a rear portion of the conductive plate 41C, and the conductive plate 41E is located behind the conductive plate 41D. The conductive plate 41F is located above the rear part of the conductive plate 41C. The number and arrangement of the conductive plates 41A to 41F are not limited to the example described here.The number and arrangement of the conductive plates 41A to 41F can be changed depending on the number, arrangement and connection ratio of the battery cells 33.

[0027] As in Fig. 4A, the left holder 31L may contain electrical power terminals 43A and 43F. The electrical power terminals 43A and 43F protrude from the resin portion 32. During use of the battery pack 30, the battery pack 30 supplies power to the drive unit 20 via the electrical power terminals 43A and 43F. As shown in Fig. As shown in Figure 7A, the electrical power terminal 43A may be formed, for example, in the circuit board 41A. The electrical power terminal 43F may be formed, for example, in the circuit board 41F.

[0028] As in Fig. 4A, the left holder 31L may also include signal terminals 43B to 43E. The signal terminals 43B to 43E also protrude from the resin portion 32. As shown in Fig. 7A, the left holder 31L may include a plurality of signal lines 42B, 42D, and 42E. The signal lines 42B, 42D, and 42E extend from the conductive plates 41B, 41D, and 41E, respectively. The signal terminal 43B may be formed at one end of the signal line 42B. Similarly, the signal terminal 43D may be formed at one end of the signal line 42D, and the signal terminal 43E may be formed at one end of the signal line 42E. The signal terminal 43C may extend from the conductive plate 41C. The terminals 43A to 43F may be arranged at a front portion of the battery pack 30 and aligned in the front-to-back direction.

[0029] As in Fig. 2, the signal terminals 43B to 43E can be connected to the circuit board 51. An IC chip for monitoring the condition of the battery cell 33 can be mounted on the circuit board 51. The IC chip can detect voltages of the signal terminals 43B to 43E and monitor the condition of the battery cell 33 (more specifically, the battery cell 33 to which the terminals 43B to 43E are connected via the signal lines 42B to 42E) based on the voltages. The electrical power terminals 43A and 43F can also be electrically connected to the circuit board 51. The IC chip can detect the voltages of the electrical power terminals 43A and 43F and monitor the condition of the battery cell 33 based on the voltages.

[0030] Hereinafter, if the circuit boards 41A to 41F are not distinguished in the description, the circuit boards are denoted by the symbol "41." If the signal lines 42B to 42E are not distinguished in the description, the signal lines are denoted by the symbol "42." If the electrical power terminals 43A and 43F and the signal terminals 43B to 43E are not distinguished in the description, the terminals are denoted by the symbol "43."

[0031] As will be described in detail below, the outer edges 41e of the two adjacent guide plates 41 (for example, the guide plates 41A and 41B) are connected by connecting sections 44a, 44b and 44e (see Fig. 9A, Fig. 10A and Fig. 11A) are connected to each other in the insert molding. Therefore, the majority of the guide plates comprise a metal plate (hereinafter referred to as “base component 40L”, see Fig. 9A). The signal line 42 also includes the base component 40L together with the conductive plate 41. After the base component 40L is fixed to the resin portion 32 by insert molding, the connecting portions 44a, 44b, and 44e are cut off by pressing, and the plurality of conductive plates 41 are separated (a cutting process, see Fig. 9B). To enable the pressing, a through hole 32b (see Fig. 4A), which penetrates the resin portion 32 in the left-right direction, is formed in the resin portion 32. The through-hole 32b is formed at the positions of the connecting portions 44a, 44b, and 44e. During the pressing process, the connecting portions 44a, 44b, and 44e are cut with a punch inserted into the through-hole 32b.

[0032] A plurality of types of connecting sections 44a to 44e (see Fig. 9A, Fig. 10A, Fig. 11A and Fig. 12A) are used in the base component 40L ( Fig. 9A), which is a base of the plurality of guide plates 41. If the types are not distinguished in the description, the connecting portions are hereinafter denoted by the symbol "44". Right holder

[0033] As in Fig. 3, the right holder 31R is arranged on the right side of the plurality of battery cells 33. Similar to the left holder 31L, the right holder 31R includes the resin portion 32 and a plurality of conductive plates 41G to 41K (see Fig. 5). Each of the conductive plates 41G to 41K includes a plurality of welded portions 41a. Each of the welded portions 41a is welded to the terminal 33a on the right side of the battery cell 33. Similar to the left holder 31L, the slot 41b, which has a substantially 90-degree H-shape, may be formed in the welded portion 41a. The resin portion 32 and the conductive plates 41G to 41K of the right holder 31R are formed by insert molding, and the conductive plates 41G to 41K are held by the resin portion 32.

[0034] The majority of recesses 32a (see Fig. 3) may be formed on a left surface (a surface facing the battery cell 33) of the resin portion 32. Each of the right portions of the plurality of battery cells 33 may be fitted into the plurality of recesses 32a, respectively.

[0035] As in Fig. As shown in Figure 7B, the right holder 31R may include signal terminals 43G to 43K. The signal terminals 43G to 43K protrude beyond the outside of the resin portion 32. Similar to the left holder 31L, the right holder 31R may also include signal lines 42G to 42K extending from the conductive plates 41G to 41K to the signal terminals 43G to 43K.

[0036] As in Fig. 2, the signal terminals 43G to 43K are connected to the circuit board 51. The control IC chip mounted on the circuit board 51 can detect voltages of the signal terminals 43G to 43K and monitor a state of the battery cell 33 (more specifically, the battery cell 33 welded to the circuit boards 41G to 41K to which the terminals 43G to 43K are connected via the signal lines) based on the voltages.

[0037] If the circuit boards 41G to 41K are not distinguished in the description, the circuit boards are denoted by the symbol "41" hereinafter. If the signal lines 42G to 42K are not distinguished in the description, the signal lines are denoted by the symbol "42", and if the signal terminals 43G and 43K are not distinguished in the description, the terminals are denoted by the symbol "43".

[0038] Similar to the guide plate 41 of the left holder 31L, the plurality of guide plates 41 of the right holder 31R are connected to each other by the connecting portion 44 in the injection molding and comprise a metal plate (hereinafter referred to as the “base component”). The signal line 42 extending from the guide plate 41 also comprises the base component together with the guide plate 41. After the base component is fixed to the resin portion 32 by insert injection molding, the connecting portions 44 are cut through by pressing, and the plurality of guide plates 41 are separated (by the cutting process). To enable the pressing, the through hole 32b (see Fig. 3) that penetrates the resin portion 32 in the left-right direction is formed in the resin portion 32. The through holes 32b are formed at the positions of the connecting portions 44, respectively. During the pressing process, the connecting portions 44 are cut with a punch inserted into the through hole 32b. Connection of a plurality of battery cells

[0039] In the battery pack 30, a plurality of battery cells 33 connected in parallel constitute a set. A plurality of sets are connected in series. For example, in the battery pack 30, three battery cells 33 connected in parallel constitute a set. Ten sets are connected in series.

[0040] An electrical connection of the battery cell 33 is described with reference to the Fig. 7A and Fig. 7B. Fig. 7A shows the guide plate 41 of the left holder 31L. Fig. 7B shows the guide plate 41 of the right holder 31R.

[0041] In the drawings, a suffix indicating the battery cell 33 welded to the weld portion 41a of the conductive plate 41 is marked at a position of the weld portion 41a. For example, a symbol “33_1(+)” shown in Fig. 7A, indicates that the welding portion 41a at the position of the symbol is welded to the positive terminal 33a+ of the battery cell 33 in a first set. Likewise, a symbol "33_2(-)" indicates that the welding portion 41a at the position of the symbol is welded to the negative terminal 33a- of the battery cell 33 in a second set. The symbol "33_1(-)" shown in Fig. 7B indicates that the welding portion 41a at the position of the symbol is welded to the negative terminal 33a- of the battery cell 33 in the first set.

[0042] As in Fig. As shown in Fig. 7A, the electric power terminal 43A of the battery pack 30 (a positive terminal of the battery pack 30) is formed on the conductive plate 41A. The electric power terminal 43F (a negative terminal of the battery pack 30) is formed on the conductive plate 41F. The battery cells 33 are electrically connected to the conductive plates 41B to 41E of the left holder 31L and the conductive plates 41G to 41K of the right holder 31R between the conductive plate 41A and the conductive plate 41F in the order of (1) to (23) as follows.

[0043] (1) The electrical power connection 43A, (2) the conductive plate 41A of the left holder 31L, (3) the three battery cells 33 of the first set, (4) the conductive plate 41G of the right holder 31R, (5) the three battery cells 33 of the second set, (6) the conductive plate 41B of the left holder 31L, (7) three battery cells 33 of a third set, (8) the conductive plate 41H of the right holder 31R, (9) three battery cells 33 of a fourth set, (10) the conductive plate 41C of the left holder 31L, (11) three battery cells 33 of a fifth set, (12) the conductive plate 41L of the right holder 31R, (13) three battery cells 33 of a sixth set, (14) the conductive plate 41D of the left holder 31L, (15) three Battery cells 33 of a seventh set, (16) the guide plate 41J of the right holder 31R, (17) three battery cells 33 of an eighth set, (18) the guide plate 41E of the left holder 31L, (19) three battery cells 33 of a ninth set, (20) the guide plate 41K of the right holder 31R,(21) three battery cells 33 of a tenth set, (22) the conductor plate 41F of the left holder 31L, and (23) the electrical power connection 43F,

[0044] The conductive plate 41A of the left holder 31L includes three welding sections 41a, to which the positive terminals 33a+ of the three battery cells 33 are welded, respectively. The conductive plate 41F includes three welding sections 41a, to which the negative terminals 33a- of the three battery cells 33 are welded, respectively. In contrast, each of the conductive plates 41B to 41E includes six welding sections 41a. The three welding sections 41a of the six welding sections are each welded to the positive terminals 33a+ of the three battery cells 33, and the remaining three welding sections are each welded to the negative terminals 33a- of the three battery cells 33.Similarly, each of the conductive plates 41G to 41K of the right holder 31R includes the three welding portions 41a to which the positive terminals 33a+ of the three battery cells 33 are welded, respectively, and the three welding portions 41a to which the negative terminals 33a- of the three battery cells 33 are welded, respectively.

[0045] The number of battery cells 33 comprising each set is not limited to three and may be two or more than three. The number of sets connected in series may be fewer than ten or more than ten. Battery pack manufacturing process

[0046] A manufacturing method for the battery pack 30 will be described with reference to Fig. 8 described.

[0047] A base component 40L including a plurality of conductive plates 41 and signal lines 42 of the left holder 31L is prepared (S101). For example, a plurality of base components 40L can be cut out of a rectangular metal plate by pressing (punching).

[0048] Fig. 9A is a view showing an example of the base component 40L. As shown in the same drawing, the outer edges 41e of two adjacent guide plates 41 are connected to each other. Due to this structure, it is possible to reduce the amount of pressing work required to obtain a plurality of guide plates 41 and the number of parts required for the pressing work. Fig. 9B is a view showing the conductive plate 41 and the signal line 42 separated by the pressing process (the cutting process in S103) after insert molding. Connecting section of two circuit boards

[0049] Fig. 10A and Fig. 11A are enlarged views of an area X and an area XI in Fig. 9A. As in Fig. As shown in Figure 10A, the outer edge 41e of the guide plate 41B is connected to the outer edge 41e of the guide plate 41C by the connecting portion 44a. The connecting portion 44a extends from the outer edge 41e of one guide plate 41B to the outer edge 41e of another guide plate 41C along a plane parallel to the base component 40L.

[0050] As in Fig. As shown in FIG. 11A, the outer edge 41e of the guide plate 41A can be connected to the outer edge 41e of the guide plate 41B by the connecting portion 44b. The connecting portion 44b extends from the outer edge 41e of one guide plate 41A to the outer edge 41e of another guide plate 41B along the plane parallel to the base component 40L. A recess 41f is formed in the outer edge 41e of the guide plate 41B. The recess 41f will be described below.

[0051] The outer edge 41e of the guide plate 41C and the outer edge 41e of the guide plate 41D are also connected to each other. Similarly, the outer edge 41e of the guide plate 41D and the outer edge 41e of the guide plate 41E, as well as the outer edge 41e of the guide plate 41E and the outer edge 41e of the guide plate 41F, are also connected to each other.

[0052] The two adjacent guide plates 41 can be connected to each other by the plurality of connecting portions 44. This can increase the strength of the base component 40L. For example, the guide plate 41A and the guide plate 41B are connected to each other by the two connecting portions 44b. The guide plate 41B and the guide plate 41C are also connected to each other by the two connecting portions 44a.

[0053] A conductive plate 41 may be connected to the plurality of adjacent conductive plates 41. For example, the conductive plate 41B is connected to the conductive plate 41A located in front of the conductive plate 41B, to the conductive plate 41C located above the conductive plate 41B, and to the conductive plate 41D located behind the conductive plate 41B. Accordingly, the base component 40L can be used in the manufacture of the battery pack 30 with a large number of conductive plates 41. Connection section between signal line and circuit board

[0054] As described above, the left holder 31L contains the signal lines 42, each extending from the guide plates 41. The signal lines 42 can be arranged along the outer edge 41e of another guide plate 41 and connected to the outer edge 41e of the other guide plate 41. Accordingly, it is possible to prevent misalignment of the signal lines 42 in the mold cavity when performing the insert molding to be described below (in S102).

[0055] As in Fig. 12A, the signal line 42D may be arranged, for example, along the outer edge 41e of the conductive plate 41C. The outer edge 41e of the conductive plate 41C is connected to the signal line 42D by the connecting portion 44c. Similar to the connecting portion 44a described above, the connecting portion 44c extends along the plane parallel to the base component 40L.

[0056] The outer edge 41e of the conductive plate 41C can be connected to the signal line 42D by a plurality of connecting portions 44c arranged at intervals along the outer edge 41e of the conductive plate 41C. As shown in Fig. 12A, the signal line 42E can be connected to the outer edge 41e of the conductive plate 41F through the plurality of connecting portions 44c similarly to the signal line 42D. Connection section between two signal lines

[0057] The plurality of signal lines 42 can be arranged between the outer edges 41e of the two conductive plates 41. In this case, the plurality of signal lines 42 can be connected to one another via the connecting section 44. In the Fig. In the example shown in Figure 12A, the two signal lines 42D and 42E are arranged between the outer edge 41e of the conductive plate 41F and the outer edge 41e of the conductive plate 41C. The two signal lines 42D and 42E are connected to each other via the connecting section 44d (see Fig. 9A and Fig. 12A). Due to the structure, even with a large number of signal lines 42, it is possible to prevent misalignment of the individual signal lines 42.

[0058] In contrast to the example in Fig. 12A, a signal line 42 can be arranged between the two circuit boards 41. Here, one signal line 42 can be connected to one or both of the two circuit boards 41. Insert injection molding

[0059] The left holder 31L is manufactured using the base component 40L (S102) by insert injection molding. After the base component 40L is placed in a cavity of a mold, the cavity is filled with molten resin (the material of the resin portion 32) to obtain the resin portion 32 that holds the base component 40L. Here, the through holes 32b penetrating the resin portion 32 in the left-right direction are formed at positions corresponding to the plurality of connecting portions 44. The connecting portion 44 is open to the right and left sides of the left holder 31L via the through hole 32b. A plurality of fixing holes 32e penetrating the resin portion 32 (see Fig. 4A), can be trained in S102. Cutting process

[0060] Next, the connecting portion 44 is cut by pressing (more precisely, piercing) to separate the plurality of interconnected circuit boards 41 and signal lines 42 (S103). Fig. 13A to 13C are cross-sectional views illustrating the cutting process. Fig. For example, Figs. 13A to 13C show a cross section of the left holder 31L along a line XIII-XIII in Fig. 10A.

[0061] As in Fig. 13A, the through-hole 32b may include a small-diameter portion 32b1 and a large-diameter portion 32b2. As described above, the connecting portion 44 is exposed via the through-hole 32b on the right and left sides of the left holder 31L. As shown in Fig. 13B, a die 91 having a recess 91a formed therein is inserted into the large-diameter portion 32b2, and a punch 92 is inserted into the small-diameter portion 32b1. In this way, each of the connecting portions 44 is cut. As a result, as shown in Fig. 13C, the two adjacent guide plates 41 are separated. The shape and structure of the punch 92 are not particularly limited as long as the connecting portion 44 can be cut.

[0062] In the thus formed left holder 31L, the through hole 32b is located between the outer edges 41e of the two guide plates 41, which are adjacent to each other. More specifically, the center C1 of the through hole 32b (see Fig. 13C) between the outer edges 41e of the two guide plates 41 that are adjacent to each other. As a result, the outer edge 41e of one guide plate 41 and the outer edge 41e of the other guide plate 41 each have a region that lies within the through-hole 32b of the resin portion 32 (see Fig. 13C) is exposed.

[0063] In the cutting process of S103, the plurality of connecting portions 44 can be cut simultaneously. That is, the plurality of connecting portions 44 can be cut with a single pressing device (pressing process).

[0064] The connecting section 44 connecting the signal line 42 and the circuit board 41 is formed by the same method as in the Fig. 13A to 13C. As a result, the plurality of through-holes 32b aligned along the outer edge 41e of the conductive plate 41 are formed between the signal line 42 and the outer edge 41e of the conductive plate 41. The center C1 of each of the through-holes 32b (see Fig. 13C) is located between the signal line 42 and the outer edge 41e of the conductive plate 41. The signal line 42 and the outer edge 41e of the conductive plate 41 each have portions exposed within the through hole 32b. Right holder

[0065] The right holder 31R is manufactured in a similar manner to the left holder 31L. Specifically, a base component including the plurality of conductive plates 41 and the plurality of signal lines 42 of the right holder 31R is first prepared (S104). Similar to the base component 40L, the outer edges 41e of the two adjacent conductive plates 41 in the base component can be connected to each other. The signal line 42 can be connected to the outer edge 41e of the conductive plate 41. The two adjacent signal lines 42 can be connected to each other.

[0066] Next, the right holder 31R is molded by insert molding using the base component prepared in S104 (S105). Here, the through holes 32b penetrating the resin portion 32 in the left-right direction are formed at positions corresponding to the plurality of connecting portions 44. The plurality of fixing holes 32e (see Fig. 3) can be introduced into the resin portion 32 during molding in S105.

[0067] Subsequently, the connecting portion 44 is cut by pressing (more precisely, by piercing) to separate the interconnected circuit boards 41 and signal lines 42 (S106). During the cutting process of S106, the plurality of connecting portions 44 can be cut simultaneously. That is, the plurality of connecting portions 44 can be cut by a single pressing device (pressing process). Assembly process

[0068] Next, the majority of battery cells 33 are each inserted into the majority of the central holder 34 (see Fig. 3) (S107). Then, the battery cells 33, the left holder 31L, and the right holder 31R are assembled in the left-right direction (S108). At this time, the holders 31L and 31R can be fastened to each other by inserting fasteners such as bolts and nuts into the fastening holes 32e formed in the resin portions 32 of the holders 31L and 31R. The assembly is not limited to the method described above. For example, the plurality of battery cells 33 can be inserted into the left holder 31L (or the right holder 31R), the center holder 34 can be inserted into the plurality of battery cells 33, and then the right holder 31R (or the left holder 31L) can be mounted thereon. Welding process

[0069] Next, the welded portion 41a of the left holder 31L is welded to the terminal 33a on the left side of the battery cell 33, and the welded portion 41a of the right holder 31R is welded to the terminal 33a on the right side (S109). Thus, the battery pack 30 is manufactured.

[0070] In S109, when a position of the left holder 31L is aligned with a position of the battery cell 33, the positions of the plurality of conductive plates 41 of the left holder 31L coincide with the positions of the battery cells 33. When a position of the right holder 31R is aligned with the position of the battery cell 33, the positions of the plurality of conductive plates 41 of the right holder 31R coincide with the positions of the battery cells 33. Accordingly, the welding process can be simplified. Details of the connection section

[0071] In the following, the connecting section 44 between the two adjacent circuit boards 41 and the connecting section 44 between the circuit board 41 and the signal line 42 are described in more detail.

[0072] As in Fig. As shown in Figure 10A, the outer edges 41e of the two adjacent guide plates 41 can be connected to each other by the relatively short connecting portion 44a. For example, the connecting portion 44a can be shorter than the diameter of the through-hole 32b (more precisely, the diameter of the small-diameter portion 32b1). When the length of the connecting portion 44a is as described above, the entire connecting portion 44a can be cut by the cutting process in S103 and S106. Fig. 8 can be cut as shown in Fig. 10B.

[0073] The cutting process can produce a recess 41g (see Fig. 10B) are formed in the outer edge 41e of one conductive plate 41 and the outer edge 41e of another conductive plate 41. When the recess 41g is used, the distance between the outer edges 41e of the two adjacent conductive plates 41 can be shortened. This can increase the area of ​​the conductive plate 41 and reduce the electrical resistance of the conductive plate 41. In the finally obtained battery pack 30, an inner edge of the recess 41g is exposed within the through-hole 32b formed in the resin portion 32.

[0074] As in Fig. As shown in Figure 11A, the recess 41f may be formed in the outer edge 41e of one conductive plate 41 (41B). Then, the connecting portion 44b may extend from the outer edge 41e of the other conductive plate 41 (41A) and be connected to the inner side of the recess 41f. Also, in the structure, the distance between the outer edges 41e of the two adjacent conductive plates 41 can be shortened. A sufficient length of the connecting portion 44b can be ensured. Since the distance between the two outer edges 41e is short, an area of ​​the conductive plate 41 can be increased, and an electrical resistance of the conductive plate 41 can be reduced.

[0075] If the guide plates 41 as in Fig. 11A, only a part of the connecting section 44b can be connected as shown in Fig. 11B represented by the cutting process in S103 and S106 of Fig. 8. Then, a part of the connecting portion 44b (a projection 41h) may remain on the outer edge 41e of one guide plate 41 (41A). A part of the connecting portion 44b (a projection 41i) may also remain on the outer edge 41e of another guide plate 41 (41B). In this case, the through-hole 32b may be located between the outer edge 41e of one guide plate 41 (41A) and the inner edge of the recess 41f of the other guide plate 41 (41B). More specifically, the center C1 of the through-hole 32b ( Fig. 13C) between the outer edge 41e of one conductive plate 41 (41A) and the inner edge of the recess 41f of the other conductive plate 41 (41B). In the finally obtained battery pack 30, the projections 41h and 41i are exposed within the through-hole 32b formed in the resin portion 32.

[0076] If the distance between the outer edges 41e of the two guide plates 41, which are adjacent to each other, is large, the Fig. 10B shown recess 41g and the one in Fig. 11A, the recess 41f shown may also not be formed. For example, as shown in Fig. 9A, the guide plate 41E and the guide plate 41F are connected to each other via the connecting section 44e. In this case, as shown in Fig. 9B, only a middle part of the connecting section 44e in the in S103 and S106 of Fig. 8 shown cutting process.

[0077] The connecting portions 44a, 44b and 44e described above can also be used for the connections of the other circuit boards 41D, 41E and 41F.

[0078] As in Fig. As shown in Figure 12A, the conductive plate 41 (41C) and the signal line 42 (42D) may also be connected to each other by the relatively short connecting portion 44c. For example, the connecting portion 44c may be shorter than the diameter of the through-hole 32b (more precisely, the diameter of the small-diameter portion 32b1). When the length of the connecting portion 44c is as described above, the entire connecting portion 44c may be formed by the cutting process in S103 and S106. Fig. 8 can be cut as shown in Fig. 12B.

[0079] The cutting process can produce a recess 41j (see Fig. 12B) in the outer edge 41e of the guide plate 41, and a recess 42a (see Fig. 12B) can be formed at an edge of the signal line 42. According to the structure, the distance between the outer edge 41e of the conductive plate 41 and the signal line 42 can be shortened. As a result, the area of ​​the conductive plate 41 can be increased and the thickness of the signal line 42 can be increased, thereby reducing the electrical resistance of the conductive plate and the signal line. The connection structure can be applied to a connection structure between another signal line and another conductive plate (for example, a connection structure between the signal line 42E and the conductive plate 41F). Position of the through hole

[0080] The majority of battery cells 33 aligned in the front-to-back direction have a plurality of columns. As shown in Fig. As shown in Figure 5, the plurality of battery cells 33 form a first column S1, a second column S2, a third column S3, and a fourth column S4. The positions of the battery cells 33 arranged in two adjacent columns are not aligned in the front-back direction. When the battery cells 33 are viewed in the left-right direction, as shown in Fig. 6, three adjacent battery cells 33 are located at the vertices n1 to n3 of an equilateral triangle T. For example, the centers of the three battery cells 33 can each be located at the vertices n1 to n3 of the equilateral triangle T. By arranging the battery cells 33, the arrangement density of the battery cells 33 can be increased and the battery pack 30 can be reduced in size.

[0081] The description "the three battery cells 33 are located at the vertices n1 to n3 of the equilateral triangle T" does not necessarily mean that the positions of the center points C of the three battery cells 33 completely coincide with the positions of the vertices n1 to n3. Indeed, the positions of the center points C of the three battery cells 33 may not coincide with the positions of the respective vertices n1 to n3. When the three battery cells 33 are viewed in the left-right direction, the vertices n1 to n3 may each partially overlap the three battery cells 33.

[0082] As described above, the through holes 32b are provided in the resin portion 32 at the positions of the connecting portions 44a to 44e ( Fig. 10A, Fig. 11A and Fig. 12A). When the battery cells 33 are viewed in the left-right direction, as in Fig. 6, the through hole 32b is formed in the center C of the equilateral triangle T. When the position of the through hole 32b is set in this way, a sufficient distance can be secured between the through hole 32b and the battery cell 33.

[0083] The description "the through-hole 32b is formed at the center C of the equilateral triangle T" does not necessarily mean that the center of the through-hole 32b completely coincides with the center C of the equilateral triangle T. The center of the through-hole 32b may be offset from the center C of the equilateral triangle T.

[0084] The arrangement of the battery cells 33 is not limited to the Fig. 6 example shown. Fig. 14 is a view showing a modified example of the arrangement of the battery cells 33. In the drawing, four adjacent battery cells 33 are located at the corners n1 to n4 of a square L, respectively. For example, the centers of the four battery cells 33 may be located at the corners n1 to n4 of the square L, respectively. Here, the through-hole 32b may be formed at the center C of the square L. By thus determining the position of the through-hole 32b, the distance between the through-hole 32b and the battery cell 33 can be secured.

[0085] The description "the four battery cells 33 are located at the corner points n1 to n4 of the square L" does not necessarily mean that the positions of the center points C of the four battery cells 33 completely coincide with the positions of the corner points n1 to n4. Indeed, the positions of the center points C of the four battery cells 33 may also be inconsistent with the positions of the respective corner points n1 to n4. When the four battery cells 33 are viewed from the left-right direction, the corner points n1 to n4 may each partially overlap the four battery cells 33. The description "the through-hole 32b may be formed at the center C of the square L" does not necessarily mean that the center of the through-hole 32b completely coincides with the center C of the square L. Indeed, the center of the through-hole 32b may be offset from the center C of the square L. Summary

[0086] (1) As described above, the battery pack 30 includes a plurality of battery cells 33, each of which includes the terminal 33a at one end in the left-right direction and the left holder 31L. The left holder 31L includes the resin-molded resin portion 32 and the plurality of lead plates 41 held by the resin portion 32. The plurality of battery cells 33 are aligned in two directions orthogonal to the left-right direction. The plurality of lead plates 41 includes the first lead plate 41 (for example, the lead plate 41B) connected to the terminal 33a of the first battery cell 33 and the second lead plate 41 (for example, the lead plate 41C) connected to the terminal 33a of another battery cell 33. In the resin portion 32, the first through hole 32b is formed, which penetrates the resin portion 32 in the left-right direction.The first through hole 32b is located between the outer edges 41e of the two guide plates 41.

[0087] According to the battery pack 30, the manufacturing process thereof can be simplified. For example, a method may be adopted in which the left holder 31L is formed by insert molding using the base component 40L including a plurality of interconnected conductive plates 41, and then the interconnected conductive plates 41 are separated with the punch 92 inserted into the first through-hole 32b. In this way, it is possible to reduce the amount of pressing required to obtain the plurality of conductive plates 41 and the number of parts required for the pressing. When a position of the left holder 31L is aligned with a position of the battery cell 33, the positions of the plurality of conductive plates 41 coincide with the positions of the battery cells 33.As a result, the welding process of the conductive plates 41 of the left holder 31L and the battery cells 33 can be simplified.

[0088] (2) In the structure of (1), the outer edges 41e of the two guide plates 41 each have the portion exposed within the first through hole 32b.

[0089] (3) In the structure of (1) or (2), the three adjacent battery cells 33 may be arranged at the vertices n1 to n3 of the equilateral triangle T when the battery cells 33 are viewed in the left-right direction. The first through-hole 32b may be located at the center C of the equilateral triangle T. According to the structure, a sufficient distance between the first through-hole 32b and the battery cell 33 is easily ensured.

[0090] (4) In the structure of (1) or (2), the four adjacent battery cells 33 may be located at the vertices n1 to n4 of the square L, respectively, when the majority of the battery cells 33 are viewed in the left-right direction. The center point C of the square L may be located within the first through-hole 32b. According to this structure, a sufficient distance between the first through-hole 32b and the battery cell 33 is easily ensured.

[0091] (5) In the structure according to any one of (1) to (4), the left holder 31L may include the signal line 42 (for example, the signal line 42D) electrically connected to the circuit board 51 and the conductive plate 41 (for example, the conductive plate 41C). The signal line 42 may be arranged along the outer edge 41e of the conductive plate 41. A second through-hole 32b may be formed in the resin portion 32, penetrating the resin portion 32 in the left-right direction. The second through-hole 32b may be located between the signal line 42 and the outer edge 41e of the conductive plate 41.

[0092] According to this structure, it is possible to realize a manufacturing process in which the left holder 31L is formed by insert molding using the base component 40L including the signal line 42 and the interconnected lead plate 41, and then the lead plate 41 and the interconnected signal line 42 are separated with the punch 92 inserted into the second through-hole 32b. Accordingly, when the position of the left holder 31L is aligned with the position of the battery cell 33, the position of the signal line 42 can be optimized, thereby enabling the battery pack 30 to be easily assembled.

[0093] (6) In the structure of (5), the signal line 42 and the outer edge 41e of the conductive plate 41 each have a portion exposed within the second through-hole 32b.

[0094] (7) In the structure according to any one of (1) to (6), the recess 41g may be formed in the outer edge 41e of the conductive plate 41 (for example, the conductive plate 41B). The inner edge of the recess 41g may be exposed in the first through-hole 32b. According to the structure, it is possible to shorten the distance between the outer edges 41e of the two adjacent conductive plates 41. As a result, the area of ​​each of the conductive plates 41 can be increased, and the electrical resistance of the conductive plate 41 can be reduced.

[0095] (8) In the structure of (7), the recess 41g may be formed in the outer edge 41e of the other guide plate 41 (for example, the guide plate 41C). The inner edge of the recess 41g may be exposed in the first through-hole 32b. According to this structure, it is possible to further shorten the distance between the outer edges 41e of the two adjacent guide plates 41.

[0096] (9) In the structure according to any one of (1) to (6), the outer edge 41e of one guide plate 41 (for example, the guide plate 41A) may include the protrusion 41h extending toward the outer edge 41e of another guide plate 41 (for example, the guide plate 41B). The protrusion 41h may be exposed within the first through-hole 32b.

[0097] (10) In the structure of (9), the recess 41f may be formed in the outer edge 41e of the conductive plate 41B. The first through-hole 32b may be arranged between the outer edge 41e of the conductive plate 41A and the inner edge of the recess 41f formed in the outer edge 41e of the conductive plate 41B. According to the structure, the distance between the outer edge 41e of the conductive plate 41B and the outer edge 41e of the conductive plate 41A can be shortened. Thereby, the area of ​​each of the conductive plates 41A and 41B can be increased, and the electrical resistance of each of the conductive plates 41A and 41B can be reduced.

[0098] (11) In the structure according to any one of (1) to (10), the battery pack 30 may include the right holder 31R disposed on the right side of the battery cell 33. The right holder 31R includes the resin-molded resin portion 32 and the plurality of lead plates 41 held by the resin portion 32. Also, in the resin portion 32 of the right holder 31R, the third through-hole 32b penetrating the resin portion 32 in the left-right direction is formed. The third through-hole 32b is located between the outer edges 41e of the two lead plates 41 adjacent to each other.

[0099] According to the battery pack 30, a manufacturing method is possible in which the right holder 31R is formed by insert molding using the base component 40L including a plurality of interconnected conductive plates 41, and then the interconnected conductive plates 41 are separated with the punch 92 inserted into the third through-hole 32b. In this way, it is possible to reduce the amount of pressing required to obtain the plurality of conductive plates 41 and the number of parts required for the pressing. When the position of the right holder 31R is aligned with the position of the battery cell 33, the positions of the plurality of conductive plates 41 coincide with the positions of the battery cells 33. This can facilitate the welding process of the conductive plate 41 of the right holder 31R and the battery cell 33.

[0100] (12) As described above, the manufacturing method of the battery pack 30 includes: a process of manufacturing the base component 40L including the plurality of lead plates 41 and the first connecting portion 44 (for example, the first connecting portion 44a) that connects the outer edges 41e of the two lead plates 41 (for example, the lead plates 41B and 41C) side by side; a molding process of forming the left holder 31L including the resin portion 32 that holds the base component 40L by insert molding, and forming the first through-hole 32b at the position corresponding to the first connecting portion 44 in the resin portion 32; and a cutting process of cutting the connecting portion 44 with the punch 92 inserted into the first through-hole 32b.

[0101] This manufacturing method makes it possible to reduce the amount of pressing required to obtain the plurality of conductive plates 41 and the number of parts required for the pressing processes. When the position of the left holder 31L is aligned with the position of the battery cell 33, the positions of the plurality of conductive plates 41 coincide with the positions of the battery cells 33. As a result, the welding process of the conductive plate 41 of the left holder 31L and the battery cell 33 can be simplified.

[0102] (13) The manufacturing method of (12) further includes a process of disposing the left holder 31L on the left side of the plurality of battery cells 33 and welding the terminal 33a of the battery cell 33 to the lead plate 41.

[0103] (14) In the manufacturing method according to (13), the three adjacent battery cells 33 can be arranged at the vertices n1 to n3 of the equilateral triangle T when the battery cells 33 are viewed in the left-right direction.

[0104] In the molding process, the first through-hole 32b penetrating the resin portion 32 can be formed at the center C of the equilateral triangle T. According to the manufacturing method, a sufficient distance between the first through-hole 32b and the battery cell 33 is easily ensured.

[0105] (15) In the manufacturing method according to (13), the four adjacent battery cells 33 can be arranged at the corner points n1 to n4 of the square L, respectively, when the plurality of battery cells 33 are viewed in the left-right direction. In insert molding, the first through-hole 32b penetrating the resin portion 32 can be formed at the center C of the square L. According to the manufacturing method, a sufficient distance between the first through-hole 32b and the battery cell 33 is easily ensured.

[0106] (16) In the manufacturing method according to any one of (12) to (15), the base component 40L may include the signal line 42 (for example, the signal line 42D) arranged along the outer edge 41e of the conductive plate 41 (for example, the conductive plate 41C), and a second connecting portion 44 (for example, the second connecting portion 44c) connecting the outer edge 41e of the conductive plate 41 and the signal line 42. In the molding process, a second through-hole 32b penetrating the resin portion 32 may be formed at the position corresponding to the second connecting portion 44. Thereafter, the second connecting portion 44 may be cut with the punch 92 inserted into the second through-hole 32b.

[0107] The battery pack and its manufacturing method according to the present disclosure are not limited to the examples described above.

[0108] The arrangement of the guide plate 41 is, for example, not limited to the Fig. 7A and Fig. 7B and can be modified as required.

[0109] The shape of the connecting portion 44 connecting the outer edges 41e of the two adjacent conductive plates 41 and the shape of the connecting portion 44 connecting the signal line 42 and the conductive plate 41 are not limited to the Fig. 10A, Fig. 11A and Fig. 12A. All connecting portions 44 of the base component 40L may have a sufficient length, and only a part of the connecting portions 44 may be used in the cutting processes in S103 and S106 of Fig. 8. In the finally obtained holders 31R and 31L, the Fig. 10A, Fig. 11A and Fig. 12A shown recesses 41f, 41g and 41j may also not be formed.

[0110] Although the present invention has been illustrated and described herein with reference to specific embodiments and examples, it will be readily apparent to those skilled in the art that other embodiments and examples may perform similar functions and / or achieve similar results. All such equivalent embodiments and examples are considered to be within the spirit and scope of the present invention and are intended to be covered by the following claims. QUOTES CONTAINED IN THE DESCRIPTION

[0000] This list of documents submitted by the applicant was generated automatically and is included solely for the convenience of the reader. This list is not part of the German patent or utility model application. The DPMA assumes no liability for any errors or omissions. Cited patent literature

[0000] JP 2015-053205 A

[0002] WO 2013 / 077205 A1

[0002]

Claims

[1] A battery pack (30) comprising: a plurality of battery cells (33), each having a terminal (33a) at one end on a first side in a first direction; and a first holder (31L) arranged on the first side of the plurality of battery cells (33), the first holder (31L) having a resin portion (32) formed of resin and a plurality of conductive plates (41) held by the resin portion (32), wherein the plurality of battery cells (33) includes a first battery cell (33) and a second battery cell (33) aligned in a second direction intersecting the first direction, the plurality of guide plates (41) includes a first guide plate (41) having a first edge (41e) and a second guide plate (41) having a second edge (41e) facing the first edge (41e) in the second direction, wherein the first guide plate (41) is connected to the terminal (33a) of the first battery cell (33), and the second guide plate (41) is connected to the terminal (33a) of the second battery cell (33), a first through-hole (32b) is formed in the resin portion (32) and penetrates the resin portion (32) in the first direction, and the first through-hole (32b) is located between the first edge (41e) of the first guide plate (41) and the second edge (41e) of the second guide plate (41). [2] The battery pack (30) according to claim 1, wherein the first edge (41e) of the first conductive plate (41) and the second edge (41e) of the second conductive plate (41) each have a portion exposed within the first through-hole (32b). [3] The battery pack (30) according to claim 1, wherein the plurality of battery cells (33) further includes a third battery cell (33), the first battery cell (33), the second battery cell (33) and the third battery cell (33) are each arranged at the vertices (n1 to n3) of an equilateral triangle (T) when the plurality of battery cells (33) is viewed in the first direction, and the first through-hole (32b) is located in the center (C) of the equilateral triangle (T) when the plurality of battery cells (33) is viewed in the first direction. [4] The battery pack (30) according to claim 1, wherein the plurality of battery cells (33) further includes a third battery cell (33) and a fourth battery cell (33), the first battery cell (33), the second battery cell (33), the third battery cell (33) and the fourth battery cell (33) are each arranged at corner points (n1 to n4) of a square (L) when the plurality of battery cells (33) is viewed in the first direction, and the first through-hole (32b) is located in the center (C) of the square (L) when the plurality of battery cells (33) are viewed in the first direction. [5] The battery pack (30) according to claim 1, further comprising: a circuit board (51), wherein the first holder (31L) contains a signal line (42) electrically connected to the circuit board (51) and a third circuit board (41), the signal line (42) is arranged along a third edge (41e) of the third circuit board (41), and a second through-hole (32b) is formed in the resin portion (32) and penetrates the resin portion (32) in the first direction, the second through-hole (32b) being located between the signal line (42) and the third edge (41e) of the third circuit board (41). [6] The battery pack (30) according to claim 5, wherein the signal line (42) and the third edge (41e) of the third conductive plate (41) each have an exposed portion within the second through-hole (32b). [7] The battery pack (30) according to claim 1, wherein a recess (41g) is formed in the first edge (41e) of the first guide plate (41), and an inner edge of the recess (41g) formed in the first edge (41e) is exposed within the first through-hole (32b). [8] The battery pack (30) according to claim 7, wherein a recess (41g) is formed in the second edge (41e) of the second guide plate (41), and an inner edge of the recess (41g) formed in the second edge (41e) is exposed within the first through-hole (32b). [9] The battery pack (30) according to claim 1, wherein the first edge (41e) of the first guide plate (41) includes a projection (41h) extending towards the second edge (41e) of the second guide plate (41), and the projection (41h) is exposed inside the first through hole (32b). [10] The battery pack (30) according to claim 9, wherein a recess (41f) is formed in the second edge (41e) of the second guide plate (41), and the first through-hole (32b) is arranged between the first edge (41e) of the first guide plate (41) and an inner edge of the recess (41f) formed in the second edge (41e). [11] The battery pack (30) according to claim 1, wherein the plurality of battery cells (33) each include a terminal (33a) at one end on a second side in the first direction, the battery pack (30) includes a second holder (31R) arranged on the second side of the plurality of battery cells (33), the second holder (31R) including a resin portion (32) formed of resin and a plurality of conductive plates (41) held by the resin portion (32), the plurality of battery cells (33) includes a fifth battery cell (33) and a sixth battery cell (33), the plurality of guide plates (41) of the second holder (31R) includes a fourth guide plate (41) and a fifth guide plate (41), a third through-hole (32b) is formed in the resin portion (32) of the second holder (31R), which penetrates the resin portion (32) in the first direction, and the third through-hole (32b) is located between an edge (41e) of the fourth guide plate (41) and an edge (41e) of the fifth guide plates (41). [12] A method of manufacturing a battery pack (30), the method comprising: a process for preparing a base component (40L) including a first guide plate (41), a second guide plate (41) aligned with the first guide plate (41), and a first connecting portion (44) connecting an edge (41e) of the first guide plate (41) and an edge (41e) of the second guide plate (41); a molding process for forming a holder (31L) including a resin portion (32) that holds the base component (40L) by insert molding and forming a first through-hole (32b) at a position corresponding to the first connecting portion (44) in the resin portion (32); and a cutting process for cutting the connecting portion (44) with a punch (92) inserted into the first through hole (32b). [13] The method of manufacturing a battery pack (30) according to claim 12, the method further comprising: a process for manufacturing a plurality of battery cells (33) including a first battery cell (33) and a second battery cell (33), the plurality of battery cells (33) each including a terminal (33a) at one end on a first side in a first direction; and a process of arranging the holder (31L) on the first side of the plurality of battery cells (33), welding the terminal (33a) of the first battery cell (33) to the first conductive plate (41), and welding the terminal (33a) of the second battery cell (33) to the second conductive plate (41). [14] A method for manufacturing a battery pack (30) according to claim 13, wherein the plurality of battery cells (33) further includes a third battery cell (33), the first battery cell (33), the second battery cell (33) and the third battery cell (33) are respectively arranged at the vertices (n1 to n3) of an equilateral triangle (T) when the plurality of battery cells (33) are viewed in the first direction, and the first through-hole (32b) is formed in the center (C) of the equilateral triangle (T). [15] A method of manufacturing a battery pack (30) according to claim 13, wherein the plurality of battery cells (33) further includes a third battery cell (33) and a fourth battery cell (33), the first battery cell (33), the second battery cell (33), the third battery cell (33) and the fourth battery cell (33) are each arranged at corner points (n1 to n4) of a square (L) when the plurality of battery cells (33) is viewed in the first direction, and the first through hole (32b) is formed in the center (C) of the square (L). [16] A method of manufacturing a battery pack (30) according to claim 12, wherein the base component (40L) comprises a third conductive plate (41), a signal line (42) arranged along an edge (41e) of the third conductive plate (41), and a second connecting portion (44) connecting the edge (41e) of the third conductive plate (41) and the signal line (42), the molding process includes forming a second through-hole (32b) penetrating the resin portion (32) at a position corresponding to the second connecting portion (44), and the cutting process includes cutting the second connecting portion (44) with a punch (92) inserted into the second through hole (32b).

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