JP7567448B2 - Wiring Module - Google Patents

Description

This disclosure relates to a wiring module.

High-voltage battery packs used in electric vehicles, hybrid vehicles, etc. usually have a large number of battery cells stacked and electrically connected in series or parallel by a wiring module. A conventional wiring module of this type is described in JP-A-2019-511810 (Patent Document 1 below). The battery module described in Patent Document 1 is configured to include a plurality of battery cells each having an electrode lead protruding in the front-rear direction of the battery module, and a busbar unit that integrally connects the electrode leads of the plurality of battery cells. This busbar unit includes a first busbar frame that is attached to the front of the plurality of battery cells and holds a first busbar connected to the electrode leads protruding forward, a second busbar frame that is attached to the rear of the plurality of battery cells and holds a second busbar connected to the electrode leads protruding rearward, and a sensing busbar that electrically connects the first busbar and the second busbar.

Special table 2019-511810 publication

In the above configuration, in order to detect the voltage of each battery cell, for example, it is possible to place an output connector on the first bus bar frame and connect a mating connector for external output to this connector. In this case, since it is necessary to connect a sensing bus bar to the connector, it is necessary to route the sensing bus bar on the back side of the connector, i.e., the side opposite to the mating surface where the mating connector is mated. Here, depending on the arrangement of the connector, the sensing bus bar will have to be routed on the back side, bypassing the connector, which may increase the space required to route the sensing bus bar and result in an increase in the size of the battery pack.

This disclosure was completed based on the above circumstances, and aims to provide a wiring module that can be made low-profile and space-saving.

The wiring module of the present disclosure is a wiring module attached to a plurality of energy storage elements, and includes a flexible printed circuit board and a protector that holds the flexible printed circuit board, the flexible printed circuit board includes a base film, a plurality of conductive paths arranged on the surface of the base film, and a connector having an opposing surface that faces the surface of the base film and connected to the plurality of conductive paths, the plurality of conductive paths and the electrode terminals of the plurality of energy storage elements are electrically connected, the connector has a connection portion that is connected to the plurality of conductive paths, and at least some of the plurality of conductive paths are routed from the connection portion through between the surface of the base film and the opposing surface of the connector.

This disclosure makes it possible to provide a wiring module that can be made low-profile and space-saving.

FIG. 1 is a perspective view of a battery module according to a first embodiment. FIG. 2 is a perspective view of the battery module with the cover attached. FIG. 3 is a front view of the battery module. FIG. 4 is a rear view of the battery module. FIG. 5 is a perspective view of a battery cell. FIG. 6 is a perspective view of the first bus bar module. FIG. 7 is a perspective view of the output connector. FIG. 8 is a perspective view of the cross section taken along the line AA of FIG. FIG. 9 is a perspective view showing the periphery of the output connector of the battery module. FIG. 10 is a perspective view showing the periphery of an output connector of a battery module with a cover attached. FIG. 11 is a perspective view of FIG. 9 with the output connector removed. FIG. 12 is a diagram showing the periphery of the second connector of the battery module. FIG. 13 is a perspective view of FIG. 12 with the first connector and the first flexible printed circuit board removed. FIG. 14 is an enlarged perspective view showing soldering between one side surface of the connection portion of the first bus bar and the first land. FIG. 15 is an enlarged perspective view showing soldering between the four side surfaces of the connection portion of the first bus bar and the first lands. FIG. 16 is an enlarged front view showing an output connector and a first flexible printed circuit board according to the second embodiment. FIG. 17 is a diagram of FIG. 16 with the output connector removed. FIG. 18 is an enlarged front view of the first bus bar module according to the third embodiment. FIG. 19 is a diagram of FIG. 18 with the output connector removed. FIG. 20 is an enlarged perspective view of the first bus bar module. FIG. 21 is an enlarged front view showing an output connector and a flexible printed circuit board according to the fourth embodiment. FIG. 22 is a diagram of FIG. 21 with the output connector removed. FIG. 23 is an enlarged perspective view showing an output connector and a flexible printed circuit board. FIG. 24 is a front view of the wiring module according to the fifth embodiment. FIG. 25 is a perspective view of a battery cell stack with joints. FIG. 26 is an enlarged perspective view showing the periphery of a sub-terminal of the wiring module.

[Description of the embodiments of the present disclosure]
First, embodiments of the present disclosure will be listed and described.

(1) The wiring module of the present disclosure is a wiring module attached to a plurality of energy storage elements, and includes a flexible printed circuit board and a protector that holds the flexible printed circuit board, the flexible printed circuit board includes a base film, a plurality of conductive paths arranged on a surface of the base film, and a connector having an opposing surface facing the surface of the base film and connected to the plurality of conductive paths, the plurality of conductive paths and the electrode terminals of the plurality of energy storage elements are electrically connected, the connector has a connection portion that is connected to the plurality of conductive paths, and at least some of the plurality of conductive paths are routed from the connection portion between the surface of the base film and the opposing surface of the connector.

With this configuration, at least some of the multiple conductive paths pass between the surface of the base film and the opposing surface of the connector, making it possible to reduce the space required for routing the multiple conductive paths. This makes it possible to reduce the height of the wiring module and save space.

The wiring module of the present disclosure may have the following configuration.
(2) The surface of the base film intersects with a first direction, and the connector has an opening that opens on the side opposite the opposing surface in the first direction and receives a mating connector that is to be mated with the connector.

This configuration allows the connector to be mated with the mating connector in the first direction.

Moreover, the wiring module of the present disclosure may have the following configuration.
(3) The surface of the base film intersects with a first direction, the connector opens on one side in a second direction intersecting with the first direction and has an opening for receiving a mating connector that is to mate with the connector, and the connection portion is arranged on the other side of the connector in the second direction.

This configuration allows the connector to be mated with the mating connector in the second direction.

(4) It is preferable that the plurality of conductive paths include a first conductive path routed from the connection portion in a direction opposite to the opening, and a second conductive path routed from the connection portion through between the surface of the base film and the opposing surface of the connector.

This configuration allows the wiring module to be made even lower profile and more space-saving.

(5) The second conductive path is routed from the connection portion toward the opening.

(6) It is preferable that the second conductive path is bent near the opening of the connector and routed in a direction different from the second direction. More preferably, the vicinity of the opening is specifically the other side of the opening in the second direction.

This configuration makes it easy to mate and detach the connector from the mating connector.

(7) It is preferable that a reinforcing plate is provided on the opposite side of the base film from the connector in the first direction.

This configuration improves the strength of the flexible printed circuit board against the stress applied to the flexible printed circuit board when the connector is mated with or removed from the mating connector.

(8) It is preferable that a recess is provided at the end of one side of the protector in the second direction, in which the bent second conductive path is routed.

The multiple energy storage elements to which the wiring module is attached may be further protected from the outside by being covered with a case, cover, etc. In this case, there is a risk that the second conductive path may be pinched between the protector and the cover, etc. and damaged. With this configuration, the recess increases the clearance between the protector and the cover, etc., making it less likely that the second conductive path will be pinched between the protector and the cover, etc. and damaged.

(9) It is preferable that the protector is provided with a locking portion that locks the second conductive path arranged in the recess.

With this configuration, the position of the second conductive path can be regulated by the locking portion, making it even less likely that the second conductive path will be pinched between the protector and the cover, etc., and damaged.

(10) A conductive member is connected to the electrode terminal, and the flexible printed circuit board has a land, which is connected to at least one side of the conductive member by soldering.

(11) It is preferable that the land is connected to only one side of the conductive member by soldering.

This configuration improves the work efficiency of soldering the lands and conductive members.

[Details of the embodiment of the present disclosure]
The present disclosure will be described below with reference to the embodiments. The present disclosure is not limited to these examples, but is defined by the claims, and is intended to include all modifications within the meaning and scope of the claims.

<Embodiment 1>
A first embodiment of the present disclosure will be described with reference to Figs. 1 to 13. A battery module 1 including a wiring module 10 of this embodiment is mounted on a vehicle as a power source for driving a vehicle such as an electric vehicle or a hybrid vehicle. In the following description, the direction indicated by the arrow Z is the upward direction, the direction indicated by the arrow X is the forward direction, and the direction indicated by the arrow Y is the leftward direction. Here, the front-rear direction is an example of the first direction, and the up-down direction is an example of the second direction. Note that, for multiple identical members, only some of the members may be labeled with a reference symbol, and the reference symbols of the other members may be omitted.

As shown in FIG. 1, the battery module 1 includes a battery cell stack 20L (an example of a plurality of power storage elements) and a wiring module 10 attached to the battery cell stack 20L. As shown in FIG. 2, the top, bottom, left and right sides of the battery module 1 are covered with covers 80.

[Battery cells, electrode leads]
As shown in FIG. 1, the battery cell stack 20L is configured by arranging a plurality of battery cells 20 (an example of a storage element) in the left-right direction. As shown in FIG. 5, the battery cell 20 is long in the front-rear direction and has a flat shape in the left-right direction. An electric storage element (not shown) is accommodated inside the battery cell 20. The battery cell 20 includes a pair of electrode leads 21 (an example of an electrode terminal). The pair of electrode leads 21 are disposed on both sides of the battery cell 20 in the front-rear direction, respectively, and protrude in opposite directions. The pair of electrode leads 21 are plate-shaped and have opposite polarities. That is, the electrode lead 21 on one side of the battery cell 20 in the front-rear direction is a negative electrode, and the electrode lead 21 on the other side is a positive electrode.

In this embodiment, the battery cell 20 is, for example, a secondary battery such as a lithium ion battery.

As shown in FIG. 1, the battery cell stack 20L includes electrode leads 21 that protrude forward of each battery cell 20 and electrode leads 21 that protrude rearward of each battery cell 20. As described below, the wiring module 10 of this embodiment is attached to the front and rear sides of the battery cell stack 20L, one each, and electrically connects the electrode leads 21 of each battery cell 20 on each side. The electrode leads 21 of the battery cell stack 20L are appropriately bent and cut to the required length for connection to the wiring module 10.

[Wiring modules, flexible printed circuit boards]
As shown in FIG. 1 , the wiring module 10 includes a bus bar 30 (an example of a conductive member) connected to an electrode lead 21, a flexible printed circuit board (hereinafter abbreviated as FPC) 60 connected to the bus bar 30, and a protector 70 that holds the bus bar 30 and the FPC 60.

[Base film, conductive path]
11, the FPC 60 includes a base film 62A, a plurality of conductive paths 63 arranged on the surface of the base film 62A, and a coverlay film 62B that covers the plurality of conductive paths 63. The base film 62A and the coverlay film 62B are made of synthetic resin such as polyimide having insulating properties and flexibility. The plurality of conductive paths 63 are formed of metal foil such as copper or copper alloy. Although illustration and description are omitted below, any electronic component such as a resistor, a capacitor, or a transistor can be connected to the conductive paths 63.

As shown in FIG. 8, the FPC 60 further includes an output connector 90 (an example of a connector) connected to the multiple conductive paths 63. Each conductive path 63 is electrically connected to an external ECU (Electronic Control Unit) (not shown) by the output connector 90. The ECU is equipped with a microcomputer, elements, etc., and has a well-known configuration with functions for detecting the voltage, current, temperature, etc. of the battery cells 20, controlling the charging and discharging of each battery cell 20, etc.

The FPC 60 is divided into a first FPC 40 (see FIG. 6) including an output connector 90, and a second FPC 50 (see FIG. 4). As shown in FIG. 12, a first connector 41 is provided at an end of the first FPC 40, and a second connector 51 is provided at an end of the second FPC 50. The first connector 41 and the second connector 51 are capable of being fitted to and detached from each other, thereby allowing the FPC 60 to be separated into separate pieces.

As shown in FIG. 1, the member of the wiring module 10 that is attached to the front side of the battery cell stack 20L is the first bus bar module 10A, and the member that is attached to the rear side of the battery cell stack 20L is the second bus bar module 10B.

As shown in FIG. 3, the first busbar module 10A includes a first busbar 30A (an example of a conductive member) connected to the electrode lead 21 protruding forward from the busbar 30, a first FPC 40 connected to the first busbar 30A, and a first protector 70A (an example of a protector) of the protector 70 that holds the first busbar 30A and the first FPC 40. The first busbars 30A arranged at the left and right ends of the first busbar module 10A function as electrode terminals of the battery module 1.

As shown in FIG. 4, the second busbar module 10B includes a second busbar 30B (an example of a conductive member) connected to the electrode lead 21 protruding rearward from the busbar 30, a second FPC 50 connected to the second busbar 30B, and a second protector 70B (an example of a protector) that holds the second busbar 30B and the second FPC 50 among the protectors 70.

As shown in Figures 1 and 2, when the first bus bar module 10A and the second bus bar module 10B are assembled to the battery cell stack 20L, the outer surface 22 of the battery cell stack 20L, except for the front and rear sides, is covered by a cover 80. The first FPC 40 extending in the front-rear direction is disposed on the upper outer surface 22U of the battery cell stack 20L and is covered by the upper cover 80U.

[First protector, recess, and locking portion]
The first protector 70A is made of insulating synthetic resin and has a plate shape as shown in FIG. 6. A plurality of electrode receiving portions 71 are provided in the vertical center of the first protector 70A. The plurality of electrode receiving portions 71 are formed in parallel in the horizontal direction, penetrating in the front-rear direction, and have a rectangular shape that is long in the vertical direction. A groove portion 72 that holds the first bus bar 30A is provided on the upper side of the first protector 70A. A groove-shaped recess 73A that is recessed downward is formed in the horizontal center of the upper part of the first protector 70A. As shown in FIG. 9, the first FPC 40 (including the second conductive path 44) bent at the upper end of the first protector 70A is passed through the recess 73A. In detail, the first FPC 40 bent downward at a right angle at the front end of the outer surface 22U of the battery cell stack 20L extends downward along the front surface of the recess 73A , then bent forward at a right angle, extends forward along the lower surface of the recess 73A , and then bent downward at a right angle. A rod-shaped locking portion 74A is provided on the inner wall on the right side of the recess 73A and protrudes to the left. The locking portion 74A is disposed at the rear end of the first protector 70A. The first FPC 40 passed through the recess 73A is locked inside the recess 73A by the locking portion 74A. Since the distance from the side surface on the rear end side of the recess 73A to the locking portion 74A is larger than the maximum dimension of the plate thickness of the first FPC 40, the first FPC 40 is held in the recess 73A in a manner that does not protrude forward. As shown in FIG. 10, when the upper outer surface 22U (see FIG. 1) of the battery cell stack 20L is covered by the upper cover 80U, the first FPC 40 is passed through the recess 73A and is engaged inside the recess 73A by the engaging portion 74A, thereby preventing the first FPC 40 from being pinched between the first protector 70A and the upper cover 80U and being damaged.

[Second protector]
As shown in FIG. 4, the second protector 70B has an electrode receiving portion 71, a groove portion 72, a recess 73B, and a locking portion 74B, similar to the first protector 70A. The recess 73B is formed on the right side of the upper portion of the second protector 70B. As shown in FIG. 12, the first FPC 40 (including the second conductive path 44) bent at the upper end of the second protector 70B is passed through the recess 73B. In detail, the first FPC 40 bent at a right angle downward at the rear end of the outer surface 22U of the battery cell stack 20L extends downward along the rear surface of the recess 73B, then bent at a right angle backward, extends backward along the lower surface of the recess 73B, and then bent at a right angle downward. A rod-shaped locking portion 74B is provided on the inner wall on the left side of the recess 73B so as to protrude to the right. The locking portion 74B is disposed at the front end of the second protector 70B. The first FPC 40 passed through the recess 73B is locked inside the recess 73B by the locking portion 74B. Since the distance from the side surface on the front end side of the recess 73B to the locking portion 74B is greater than the maximum dimension of the plate thickness of the first FPC 40, the first FPC 40 is held in the recess 73B in a manner that does not protrude rearward. As a result, similar to the above description of the recess 73A and the locking portion 74A of the first protector 70A, the first FPC 40 is prevented from being pinched between the second protector 70B and the upper cover 80U and being damaged when the upper cover 80U is assembled.

[Busbar]
The bus bar 30 has a plate-like shape and is formed by processing a conductive metal plate. The bus bar 30 includes a first bus bar 30A held by the first bus bar module 10A and a second bus bar 30B held by the second bus bar module 10B. As shown in Figs. 3 and 6, the first bus bar 30A is held in a groove 72 provided on the upper side of the first protector 70A so that the plate thickness direction is the left-right direction. As shown in Fig. 3, a connection portion 32 is provided at the lower part of the first bus bar 30A. The connection portion 32 is electrically connected to a first conductive path 43 of the first FPC 40 (described later) by soldering. As shown in Fig. 6, the central part of the first bus bar 30A is a main body portion 31 to which the electrode lead 21 is connected. As shown in Fig. 3, when the first bus bar module 10A is attached to the front side of the battery cell stack 20L, the electrode leads 21 protruding forward are inserted into electrode receiving portions 71 of the first protector 70A, and the main body portion 31 is connected by laser welding to the electrode leads 21 inserted into the electrode receiving portions 71. As shown in Fig. 4, like the first bus bar 30A, the second bus bar 30B is also held in a groove portion 72 of the second protector 70B, and is electrically connected at the connection portion 32 to a third conductive path 53 (described later) of the second FPC 50. The main body portion 31 of the second bus bar 30B is connected to the electrode leads 21 protruding rearward by laser welding.

[First FPC, First Base Film]
11, the first FPC 40 includes a first base film 42A (an example of a base film) that is divided on the first protector 70A side of the base film 62A, a first conductive path 43 and a second conductive path 44 that are arranged on the first base film 42A among the plurality of conductive paths 63, and a first coverlay film 42B that covers the first conductive path 43 and the second conductive path 44 of the coverlay film 62B. An opening is provided in advance in the first coverlay film 42B, and ends of the first conductive path 43 and the second conductive path 44 are exposed. This allows electrical connection by soldering at the ends of the first conductive path 43 and the second conductive path 44.

[Reinforcing plate]
As shown in FIG. 3, the first FPC 40 has an upside-down T-shape when viewed from the front. The first FPC 40 is fixed to the first protector 70A by adhesive or the like. An output connector 90 is provided at the upper end of the portion of the first FPC 40 fixed to the first protector 70A. As shown in FIG. 9 and FIG. 11, the output connector 90 is provided in front of the first base film 42A. As shown in FIG. 8, a reinforcing plate 45 is provided on the opposite side (rear side) of the output connector 90 in the front-rear direction of the first base film 42A. The reinforcing plate 45 is attached to the rear surface of the first base film 42A by adhesive or adhesive. As shown in FIG. 6, the first FPC 40 is bent at the upper end of the first protector 70A and extends further rearward. As shown in FIG. 1, the portion of the first FPC 40 extending in the front-rear direction is disposed on the upper outer surface 22U of the battery cell stack 20L. 12, the rear end portion of the first FPC 40 is provided with a first connector 41. The first connector 41 is in the shape of a block. The first connector 41 is inserted into a second connector 51 (described later) and is adapted to fit with the second connector 51.

[Surface, first conductive path]
As shown in FIG. 11, the portion of the first FPC 40 that is fixed to the front surface of the first protector 70A is disposed perpendicular to the front-rear direction. Therefore, the first base film 42A has a surface 42S perpendicular to the front-rear direction in the first protector 70A. The first conductive path 43 has an upper end 43A disposed on the surface 42S in a forward facing position. As shown in FIG. 8, the upper end 43A is soldered to the connection portion 92A of the output connector 90 and electrically connected. As shown in FIG. 11, the first conductive path 43 extends downward from the upper end 43A. At the end of the first conductive path 43 opposite to the upper end 43A, a first land 43B (an example of a land) is formed as shown in FIG. 3. The first land 43B is made of the same metal foil as the first conductive path 43 and has a rectangular shape. The first lands 43B are arranged in parallel in the left-right direction on the lower side of the first FPC 40. 14, the first land 43B is formed so as to be disposed on the right side of the connection portion 32 of the first bus bar 30A, and is electrically connected to the right side surface of the connection portion 32 of the first bus bar 30A by solder S. In this manner, by adopting a configuration in which the first land 43B and one side surface of the connection portion 32 of the first bus bar 30A are soldered, the soldering work can be efficiently performed using a general soldering iron.

The first land 43B may be formed to be arranged on both the left and right sides or the periphery of the connection portion 32 of the first busbar 30A, and may be soldered to multiple side surfaces of the connection portion 32 of the first busbar 30A. For example, as shown in FIG. 15, the first land 43B may be arranged on the periphery of the connection portion 32 of the first busbar 30A, and connected to four side surfaces of the connection portion 32 of the first busbar 30A by solder S. In this case, by making the portion connected by solder S large, the first busbar 30A is stabilized with respect to the first FPC 40. Since the number of sides of the connection portion 32 of the first busbar 30A to be soldered increases, work efficiency may become an issue, but work efficiency can be improved by using, for example, a special soldering iron that matches the shape of the connection portion 32 of the first busbar 30A.

[Second conductive path]
As shown in FIG. 11, the second conductive path 44 has a front end 44A disposed on the surface 42S in a forward facing position. The front end 44A is disposed in parallel with the upper end 43A in the left-right direction. As shown in FIG. 8, the front end 44A is electrically connected to the connection portion 92A of the output connector 90 by soldering. As shown in FIG. 10 and FIG. 11, the second conductive path 44 extends upward from the front end 44A, is bent in the vicinity of the opening 93 of the output connector 90, and extends rearward. Here, the vicinity of the opening 93 is preferably below the upper end of the output connector 90 as shown in FIG. 8. If the second conductive path 44 is bent in such a position, when the mating connector (not shown) and the output connector 90 are mated and separated, the mating connector is less likely to come into contact with the second conductive path 44, so that the mating connector and the output connector 90 can be easily mated and separated. As shown in Fig. 9, the second conductive path 44 extending rearward is passed through the recess 73A of the first protector 70A and is arranged so as to be locked by the locking portion 74A. As shown in Fig. 12, the end of the first conductive path 43 opposite to the front end 44A is the rear end 44B. The rear end 44B is electrically connected to the connection portion 41A of the first connector 41 by soldering. The first connector 41 is adapted to be fitted from above into the second connector 51 (see Fig. 13) held by the second protector 70B, and the second conductive path 44 is bent downward at the upper end of the second protector 70B. The second conductive path 44 is passed through the recess 73B of the second protector 70B and is arranged so as to be locked by the locking portion 74B.

[Output connector, opening, opposing surface, connection part]
As shown in FIG. 7, the output connector 90 includes a housing 91 having a rectangular box shape elongated in the left-right direction, and a plurality of terminals 92. The housing 91 has an opening 93 that opens upward. The opening 93 is adapted to receive a mating connector (not shown) that is to be mated with the output connector 90. This mating connector is provided at the terminal portion of the ECU described above, and each battery cell 20 is electrically connected to the ECU by mating the output connector 90 with the mating connector. The rear surface of the housing 91 is an opposing surface 91S that faces the surface 42S when the output connector 90 is attached to the surface 42S. Metal fixing parts 94 are provided on the left-right side surfaces of the housing 91. As shown in FIG. 9 and FIG. 11, the fixing parts 94 and the fixing lands 46 provided on the surface 42S are soldered to fix the output connector 90 to the surface 42S. 8, the terminal 92 is held by the bottom wall 91A of the housing 91, and the tip of the terminal 92 extends upward inside the housing 91. The terminal 92 below the bottom wall 91A is bent backward in a crank shape, and the lower end of the terminal 92 forms a connection portion 92A. The connection portion 92A is electrically connected to the upper end portion 43A and the front end portion 44A by soldering. In this way, the output connector 90 is surface-mounted on the first FPC 40.

9 and 11, the first conductive path 43 is drawn from the upper end 43A connected to the output connector 90 to the opposite side (i.e., downward) to the direction in which the opening 93 opens. On the other hand, the second conductive path 44 is drawn from the front end 44A connected to the output connector 90 to the opening 93 side (i.e., upward) through between the surface 42S and the opposing surface 91S of the output connector 90 (see FIG. 7). As a configuration for the wiring of the second conductive path different from this embodiment, for example, the second conductive path may extend downward from the connection portion 92A so as to bypass the opposing surface 42S of the opposing surface 91S, and then be drawn backward through the right or left side of the output connector 90 (referred to as a detour wiring). However, in this embodiment, the second conductive path 44 is arranged between the surface 42S and the opposing surface 91S, so that the space required for wiring the second conductive path 44 can be reduced compared to the case where the above-mentioned detour wiring is adopted.

[Second FPC, second base film]
13, the second FPC 50 includes a second base film 52A (an example of a base film) that is divided on the second protector 70B side of the base film 62A, a third conductive path 53 (an example of a plurality of conductive paths) that is disposed on the second base film 52A among the plurality of conductive paths 63, and a second coverlay film 52B that covers the third conductive path 53 among the coverlay film 62B. An opening is provided in advance in the second coverlay film 52B, and an end of the third conductive path 53 is exposed. This allows electrical connection by soldering at the end of the third conductive path 53.

[Third conductive path]
As shown in FIG. 4, the second FPC 50 has an inverted T-shape, and the part extending up and down is disposed on the right side of the center. The second FPC 50 is fixed to the second protector 70B by adhesive or the like. The second connector 51 is provided at the upper end of the second FPC 50. Although not shown, a reinforcing plate is provided on the opposite side (front side) of the second connector 51 in the front-rear direction of the second base film 52A. The reinforcing plate is attached to the front surface of the second base film 52A by adhesive or pressure sensitive adhesive. As shown in FIG. 13, the second connector 51 has a shape that opens upward. The connection portion 51A of the second connector 51 is electrically connected to the upper end 53A of the third conductive path 53. The third conductive path 53 extends downward, and a second land 53B (an example of a land) is formed at the end opposite to the upper end 53A, as shown in FIG. 4. The second lands 53B are arranged in parallel in the left-right direction at the lower end of the second FPC 50, and are electrically connected to the connection portion 32 of the second bus bar 30B. The connection between the second lands 53B and the connection portion 32 of the second bus bar 30B is made in the same manner as the connection between the first lands 43B and the connection portion 32 of the first bus bar 30A (see FIG. 14). As shown in FIG. 12, the first connector 41 is inserted into the second connector 51, whereby the second connector 51 and the first connector 41 are fitted together, and the third conductive path 53 and the second conductive path 44 are connected. This connects the second bus bar 30B to the output connector 90.

[Assembly of wiring module to battery cell stack]
The first bus bar module 10A is attached to the front side of the battery cell stack 20L, as shown in Fig. 1. As shown in Fig. 6, the first FPC 40 extending rearward from the upper end of the first protector 70A is passed through the recess 73A in advance and disposed below and behind the locking portion 74A. As shown in Fig. 1, the electrode lead 21 protruding forward is inserted into the electrode receiving portion 71, and the electrode lead 21 and the first bus bar 30A are joined by laser welding. The second bus bar module 10B is similarly attached to the rear side of the battery cell stack 20L.

Next, as shown in FIG. 12, the first connector 41 side of the first FPC 40 is passed through the recess 73B of the second protector 70B and positioned in front of and below the locking portion 74B, and then the first connector 41 and the second connector 51 are mated. By mating the first connector 41 and the second connector 51, the output connector 90 and each bus bar 30 are electrically connected. This completes the assembly of the wiring module 10 to the battery cell stack 20L (see FIG. 1). A cover 80 is attached to the outer surface 22 of the battery cell stack 20L to which the wiring module 10 is assembled (see FIG. 2).

[Effects of the First Embodiment]
According to the first embodiment, the following actions and effects are achieved.
The wiring module 10 according to the first embodiment is a wiring module 10 attached to a battery cell stack 20L, and comprises an FPC 60 and a protector 70 that holds the FPC 60. The FPC 60 comprises a base film 62A, a plurality of conductive paths 63 arranged on a surface 42S of the base film 62A, and an output connector 90 having an opposing surface 91S that faces the surface 42S of the base film 62A and connected to the plurality of conductive paths 63. The plurality of conductive paths 63 and the electrode leads 21 of the battery cell stack 20L are electrically connected to each other. The output connector 90 has a connection portion 92A that is connected to the plurality of conductive paths 63, and at least a portion of the plurality of conductive paths 63 are routed from the connection portion 92A between the surface 42S of the base film 62A and the opposing surface 91S of the output connector 90.

According to the above configuration, at least some of the multiple conductive paths 63 pass between the surface 42S of the base film 62A and the opposing surface 91S of the output connector 90, so the space required for routing the multiple conductive paths 63 can be reduced. This makes it possible to reduce the height and space of the wiring module 10.

In the first embodiment, the surface 42S of the base film 62A intersects in the front-to-rear direction, the output connector 90 opens on the upper side intersecting the front-to-rear direction and has an opening 93 for receiving a mating connector that is to be mated with the output connector 90, and the connection portion 92A is disposed on the lower side of the output connector 90.

The above configuration allows the output connector 90 to be mated with the mating connector in the vertical direction.

In the first embodiment, the multiple conductive paths 63 include a first conductive path 43 routed from the connection portion 92A in the direction opposite to the opening 93, and a second conductive path 44 routed from the connection portion 92A between the surface 42S of the base film 62A and the opposing surface 91S of the output connector 90.

The above configuration allows the wiring module 10 to be made even lower profile and more space-saving.

In the first embodiment, the second conductive path 44 is routed from the connection portion 92A toward the opening 93. The second conductive path 44 is also bent near the opening 93 of the output connector 90 and routed rearward.

With the above configuration, the second conductive path 44 extends rearward instead of upward where the output connector 90 opens, making it easy to engage and disengage the output connector 90 with the mating connector.

In the first embodiment, a reinforcing plate 45 is provided on the opposite side of the first base film 42A from the output connector 90 in the front-rear direction.

The above configuration improves the strength of the first FPC 40 against the stress applied to the first FPC 40 when the output connector 90 is mated with or removed from the mating connector.

In the first embodiment, the upper ends of the first protector 70A and the second protector 70B are provided with recesses 73A and 73B in which the bent second conductive path 44 is routed.

According to the above configuration, the recesses 73A and 73B increase the clearance between the first protector 70A and the second protector 70B and the upper cover 80U, making it less likely that the second conductive path 44 will be pinched between the first protector 70A and the second protector 70B and the upper cover 80U and be damaged.

In the first embodiment, the first protector 70A and the second protector 70B are provided with locking portions 74A and 74B that lock the second conductive path 44 arranged in the recesses 73A and 73B.

With the above configuration, the position of the second conductive path 44 can be regulated by the locking portions 74A and 74B, and the second conductive path 44 is less likely to be pinched between the first protector 70A and the second protector 70B and the upper cover 80U and be damaged.

In embodiment 1, the electrode lead 21 is connected to a first bus bar 30A and a second bus bar 30B, and the FPC 60 has a first land 43B and a second land 53B, with the first land 43B being connected to only one side of the first bus bar 30A by soldering, and the second land 53B being connected to only one side of the second bus bar 30B by soldering.

The above configuration improves the work efficiency of soldering the first land 43B to the first bus bar 30A and the second land 53B to the second bus bar 30B.

<Embodiment 2>
A second embodiment of the present disclosure will be described with reference to Figures 16 and 17. In the following description, the same members and effects as those of the first embodiment will not be described. The direction indicated by the arrow Z is the upward direction, and the direction indicated by the arrow Y is the leftward direction. Here, the front-back direction is an example of the first direction, and the up-down direction is an example of the second direction. Note that, for multiple identical members, only some of the members may be labeled with a reference symbol, and the reference symbols of the other members may be omitted.

The wiring module of the second embodiment has a first FPC 140 and an output connector 190 instead of the first FPC 40 and the output connector 90 of the first embodiment.

As shown in FIG. 17, the first FPC 140 includes a first base film 142A, a first conductive path 143 and a second conductive path 144 arranged on the first base film 142A, and a first coverlay film 142B that covers the first conductive path 143 and the second conductive path 144.

The first base film 142A has a surface 142S perpendicular to the front-rear direction (perpendicular to the paper surface). The first conductive path 143 has an upper end 143A disposed on the surface 142S facing forward (toward the viewer in the direction perpendicular to the paper surface). The second conductive path 144 has a front end 144A disposed on the surface 142S facing forward. The front end 144A is disposed in parallel with the upper end 143A in the left-right direction. The second conductive path 144 first extends upward from the front end 144A and then extends leftward. After extending leftward, the second conductive path 144 extends upward, is bent, and routed rearward.

As shown in FIG. 16, the output connector 190 includes a housing 191 having a rectangular box shape elongated in the left-right direction, and a plurality of terminals 192. The housing 191 is provided with an opening at the top to receive a mating connector (not shown). The rear surface (the surface at the back side perpendicular to the paper surface) of the housing 191 is an opposing surface (not shown) that faces the surface 142S when the output connector 190 is attached to the surface 142S. The output connector 190 is fixed to the surface 142S by a known method (soldering or adhesive of the fixing portion, etc.). The lower end of the terminal 192 is a connection portion 192A. The connection portion 192A is electrically connected to the upper end portion 143A and the front end portion 144A by soldering. In this way, the output connector 190 is surface-mounted on the first FPC 140.

The second conductive path 144 is routed from the front end 144A connected to the output connector 190 to the left of the output connector 190, passing between the surface 142S and the opposing surface of the output connector 190 (see Figures 16 and 17). Therefore, the space required for routing the second conductive path 144 can be reduced.

<Embodiment 3>
A third embodiment of the present disclosure will be described with reference to Figures 18 to 20. In the following description, the same members and effects as those of the first embodiment will not be described. The direction indicated by the arrow Z is the upward direction, the direction indicated by the arrow X is the forward direction, and the direction indicated by the arrow Y is the leftward direction. Here, the forward and backward directions are an example of the first direction. Note that, for multiple identical members, only some of the members may be labeled with a reference symbol, and the reference symbols of the other members may be omitted.

The wiring module of embodiment 3 is configured as a first busbar module 210A attached to the front and rear of a battery cell stack (not shown) equivalent to embodiment 1. For simplicity, the first busbar module 210A attached to the front of the battery cell stack will be described in detail here. The second busbar module (not shown) attached to the rear of the battery cell stack is configured similarly to the first busbar module 210A, so a detailed description will be omitted.

As shown in Figures 18 and 20, the first bus bar module 210A includes a bus bar 230, an FPC 240 connected to the bus bar 230, an output connector 290 connected to the FPC 240, and a protector 270.

As shown in FIG. 20, the bus bar 230 is a long and narrow plate extending in the vertical direction, and is held by the protector 270 with the plate thickness extending in the horizontal direction. A connection portion 232 that is electrically connected to the FPC 240 is provided on the upper portion of the bus bar 230.

As shown in FIG. 19, the FPC 240 includes a base film 242A, a plurality of conductive paths 243 arranged on the base film 242A, and a coverlay film 242B that covers the plurality of conductive paths 243. The FPC 240 is fixed to the front surface of the protector 270 by adhesive or the like, and is arranged perpendicular to the front-rear direction. Therefore, the base film 242A has a surface 242S on the protector 270 that is perpendicular to the front-rear direction.

As shown in Figures 18 and 20, an output connector 290 is provided in front of the base film 242A. A reinforcing plate 247 is provided on the opposite side (rear side) of the output connector 290 in the front-to-rear direction of the base film 242A. The reinforcing plate 247 is attached to the rear surface of the base film 242A with an adhesive or the like. Note that in embodiment 3, unlike embodiment 1, the second bus bar module is also provided with an output connector (not shown) like the first bus bar module 210A. For this reason, the FPC 240 is not connected to the second bus bar module.

As shown in Figures 18 and 20, the output connector 290 includes a housing 291 that is a rectangular box-like shape that is long in the vertical direction, and a number of terminals 292. The housing 291 has an opening 293 that opens to the front. The opening 293 is designed to receive a mating connector (not shown). The rear surface of the housing 291 is an opposing surface (not shown) that faces the surface 242S when the output connector 290 is attached to the surface 242S.

As shown in Figures 18 and 20, a metal fixing portion 294 is provided on a side surface of the housing 291 that is perpendicular to the up-down direction. The output connector 290 is fixed to the surface 242S by soldering the fixing portion 294 to a fixing land 246 provided on the surface 242S. The rear end of the terminal 292 is bent to the left (to the right in the figure) to form a connection portion 292A. The connection portion 292A is electrically connected to a plurality of conductive paths 243 by soldering. In this way, the output connector 290 is surface-mounted on the FPC 240.

18 and 20, the plurality of conductive paths 243 include a fourth conductive path 244 arranged to the left (right in the figure) from the connection portion 292A of the output connector 290, and a fifth conductive path 245 arranged to the right (left in the figure) from the connection portion 292A through between the surface 242S of the base film 242A and the opposing surface of the output connector 290. The right end 244A of the fourth conductive path 244 and the left end 245A of the fifth conductive path 245 are arranged on the surface 242S in parallel in the vertical direction and connected to the connection portion 292A. The end of the fourth conductive path 244 opposite the right end 244A is the fourth land 244B (an example of a land). The end of the fifth conductive path 245 opposite the left end 245A is the fifth land 245B (an example of a land). The fourth land 244B and the fifth land 245B are connected to the connection portion 232 of the bus bar 230 by soldering (solder not shown), as in embodiment 1.

[Effects of the Third Embodiment]
According to the third embodiment, the following actions and effects are achieved.
In embodiment 3, surface 242S of base film 242A intersects in the front-to-rear direction, and output connector 290 opens on the opposite side (front) from the opposing surface (rear surface) in the front-to-rear direction, and has an opening 293 for receiving a mating connector that is to be mated with output connector 290.

The above configuration allows the output connector 290 to be mated with the mating connector in the front-to-rear direction.

<Embodiment 4>
A fourth embodiment of the present disclosure will be described with reference to Figures 21 to 23. In the following description, the same members and effects as those of the first embodiment will not be described. In addition, the direction indicated by the arrow Z is the upward direction, the direction indicated by the arrow X is the forward direction, and the direction indicated by the arrow Y is the leftward direction. Here, the front-back direction is an example of the first direction, and the left-right direction is an example of the second direction. Note that, for multiple identical members, only some of the members may be labeled with a reference symbol, and the reference symbols of the other members may be omitted.

The wiring module of embodiment 4 is composed of a first busbar module and a second busbar module, similar to embodiment 3, and the first busbar module and the second busbar module are not electrically connected. The following describes the output connector 390 and FPC 340 attached to the first busbar module (front wiring module).

22, the FPC 340 includes a base film 342A, a plurality of conductive paths 343 arranged on the base film 342A, and a coverlay film 342B that covers the plurality of conductive paths 343. The FPC 340 is fixed to the front surface of a protector (not shown) and is arranged perpendicular to the front-rear direction. Therefore, the base film 342A has a surface 342S that is perpendicular to the front-rear direction.

As shown in FIG. 23, the output connector 390 has a housing 391 that is a rectangular box shape that is long in the vertical direction. The housing 391 has an opening 393 that opens to the left (right in the figure). The opening 393 is designed to receive a mating connector (not shown). As shown in FIG. 21, the output connector 390 has a terminal 392. The connection portion 392A of the terminal 392 is provided on the right side of the output connector 390. The rear surface of the housing 391 (the surface at the back in the direction perpendicular to the paper surface) is an opposing surface (not shown) that faces the surface 342S when the output connector 390 is attached to the surface 342S.

As shown in FIG. 21, a metal fixing portion 394 is provided on a side surface of the housing 391 that is perpendicular to the up-down direction. The output connector 390 is fixed to the surface 342S by soldering the fixing portion 394 to a fixing land 346 provided on the surface 342S. The connection portion 392A of the terminal 392 is electrically connected to the right end portion 343A of the multiple conductive paths 343 by soldering. In this way, the output connector 390 is surface-mounted on the FPC 340.

21 and 23, in the fourth embodiment, all of the conductive paths 343 are routed from the connection portion 392A between the surface 342S of the base film 342A and the opposing surface of the output connector 390. Some of the conductive paths 343 are routed to the left of the output connector 390 and are designated as the sixth conductive path 344. The conductive paths 343 other than the sixth conductive path 344 are routed below the output connector 390 and are designated as the seventh conductive path 345. The sixth conductive path 344 and the seventh conductive path 345 are electrically connected to the bus bar at the end opposite the right end 343A (not shown).

[Effects of the fourth embodiment]
According to the fourth embodiment, the following actions and effects are achieved.
In embodiment 4, surface 342S of base film 342A intersects in the front-to-rear direction, output connector 390 opens on the left side intersecting the front-to-rear direction and has an opening 393 for receiving a mating connector that is to be mated with output connector 390, and connection portion 392A is arranged on the right side of output connector 390.

The above configuration allows the output connector 390 to be mated with the mating connector in the left-right direction.

<Embodiment 5>
A fifth embodiment of the present disclosure will be described with reference to Figures 24 to 26. In the following description, the same members and effects as those of the first embodiment will not be described. In addition, the direction indicated by the arrow Z is the upward direction, the direction indicated by the arrow X is the forward direction, and the direction indicated by the arrow Y is the leftward direction. Here, the front-back direction is an example of the first direction, and the left-right direction is an example of the second direction. Note that, for multiple identical members, only some of the members may be labeled with a reference symbol, and the reference symbols of the other members may be omitted.

The wiring module 410 of the fifth embodiment includes a first wiring module 410A (see FIG. 24) attached to the front side of the battery cell stack 420L, and a second wiring module (not shown) attached to the rear side of the battery cell stack 420L. The wiring module 410 of the fifth embodiment differs from the wiring module 10 of the first embodiment in that it does not include the bus bar 30 that connects adjacent electrode leads 21 in the first embodiment. The electrical connection between the first wiring module 410A and the battery cell stack 420L will be described in detail below.

As shown in FIG. 25, the battery cell stack 420L is configured by arranging multiple battery cells 20 in the left-right direction, and adjacent electrode leads 21 are previously joined by laser welding or the like. That is, adjacent electrode leads 21 are bent so as to approach each other and are electrically connected to form joints 21J. The joints 21J are provided so as to be parallel to the stacking direction (left-right direction) of the battery cells 20. The electrode leads 21 arranged at both ends of the battery cell stack 420L and constituting the positive or negative electrode of the entire battery cell stack 420L are terminal electrode leads 21E. The terminal electrode leads 21E are arranged to protrude forward.

24, the first wiring module 410A includes an end bus bar 30E connected to the end electrode lead 21E, a sub-terminal 35 connected to the joint 21J, a first FPC 440, and a first protector 470A. The first protector 470A is provided with an electrode receiving portion 471 that receives the joint 21J or the end electrode lead 21E. As in the first embodiment, the first FPC 440 includes a first conductive path 443 (see FIG. 26), a second conductive path (not shown), and an output connector 90.

As shown in FIG. 26, the sub-terminal 35 is a plate-shaped metal member. The sub-terminal 35 is held by the sub-terminal holding portion 475 of the first protector 470A. The lower end of the sub-terminal 35 is soldered to the sixth land 447 provided at the end of the first conductive path 443 of the first FPC 440. The upper end of the sub-terminal 35 and the joint portion 21J are electrically connected by laser welding or the like. Although not shown in the figure, the second wiring module does not include the end bus bar 30E, and other configurations related to the sub-terminal 35 are configured in the same manner as the first wiring module 410A.

As described above, in the wiring module 410 according to the fifth embodiment, it is not necessary to use a bus bar to connect adjacent electrode leads 21. This is advantageous in terms of reducing the cost and weight of the wiring module 410 and improving the efficiency of the assembly work.

<Other embodiments>
(1) In the above embodiment, the laminated battery cell 20 is used as the power storage element. However, this is not limited to this, and a power storage element other than a laminated battery cell may be used.
(2) In the above embodiment, the output connectors 90, 190 open upward, the output connector 290 opens forward, and the output connector 390 opens to the left relative to the surfaces 42S, 142S, 242S, 342S that intersect (orthogonally) in the fore-and-aft direction, but this is not limited to this and the direction in which the connectors open can be set arbitrarily.
(3) In the first embodiment, the FPC 60 is divided into the first FPC 40 on the first bus bar module 10A side and the second FPC 50 on the second bus bar module 10B side. However, this is not limited to this, and the FPC does not have to be divided.
(4) In embodiment 1, one locking portion 74A, 74B is provided for each recess 73A, 73B. However, this is not limited to this. For example, a pair of locking portions may be provided on both the left and right inner walls of the recess.
(5) In the fifth embodiment, the joint 21J of the electrode lead 21 and the first FPC 440 are connected via the sub-terminal 35, but this is not limited thereto. For example, one of the electrode lead and the first FPC constituting the joint may have a shape extending toward the other, and the two may be electrically connected directly by soldering or the like.

1: Battery module 10, 410: Wiring module 10A, 210A: First bus bar module 10B: Second bus bar module 20: Battery cell 20L, 420L: Battery cell stack 21: Electrode lead 21E: End electrode lead 21J: Joint portion 22: Outer surface 22U: Upper outer surface 30, 230: Bus bar 30A: First bus bar 30B: Second bus bar 30E: End bus bar 31: Main body portion 32, 232: Bus bar connection portion 35: Sub-terminal 40, 140, 440: First FPC
41: First connector 41A: Connection portion 42A, 142A of first connector: First base film 42B, 142B: First coverlay film 42S, 142S, 242S, 342S: Surface 43, 143, 443: First conductive path 43A, 143A, 53A: Upper end portion 43B: First land 44, 144: Second conductive path 44A, 144A: Front end portion 44B: Rear end portion 45, 247: Reinforcing plate 46, 246, 346: Fixing land 50: Second FPC
51: Second connector 51A: Connection portion of second connector 52A: Second base film 52B: Second coverlay film 53: Third conductive path 53B: Second land 60, 240, 340: FPC
62A, 242A, 342A: Base film 62B, 242B, 342B: Coverlay film 63, 243, 343: Conductive path 70, 270: Protector 70A, 470A: First protector 70B: Second protector 71, 471: Electrode receiving portion 72: Groove portion 73A, 73B: Recessed portion 74A, 74B: Locking portion 80: Cover 80U: Upper cover 90, 190, 290, 390: Output connector 91, 191, 291, 391: Housing 91A: Bottom wall 91S: Opposing surface 92, 192, 292, 392: Terminal 92A, 192A, 292A, 392A: Output connector connection portion 93, 293, 393: Opening 94, 294, 394: Fixing portion 244: Fourth conductive path 244A, 343A: Right end portion 244B: Fourth land 245: Fifth conductive path 245A: Left end portion 245B: Fifth land 344: Sixth conductive path 345: Seventh conductive path 410A: First wiring module 447: Sixth land 475: Sub-terminal holding portion S: Solder

Claims (10)

A wiring module attached to a plurality of energy storage elements,
A flexible printed circuit board;
a protector for holding the flexible printed circuit board;
the flexible printed circuit board includes a base film, a plurality of conductive paths disposed on a surface of the base film, and a connector having an opposing surface facing the surface of the base film and connected to the plurality of conductive paths;
the plurality of conductive paths are electrically connected to the electrode terminals of the plurality of storage elements;
the connector has a connection portion connected to the plurality of conductive paths,
At least some of the conductive paths are routed from the connection portion between the surface of the base film and the opposing surface of the connector ,
the plurality of conductive paths include a first conductive path and a second conductive path arranged in opposite directions from the connection portion,
the second conductive path is bent in the vicinity of the connector and arranged in a direction intersecting the surface of the base film,
The wiring module , wherein the protector is provided with a recess in which the bent second conductive path is routed . The surface of the base film intersects with a first direction,
The wiring module according to claim 1 , wherein the connector has an opening that opens on a side opposite to the opposing surface in the first direction and receives a mating connector that is to be mated with the connector. The surface of the base film intersects with a first direction,
the connector has an opening that opens on one side in a second direction intersecting the first direction and receives a mating connector that is to be mated with the connector,
The wiring module according to claim 1 , wherein the connection portion is disposed on the other side of the connector in the second direction. The first conductive path is arranged from the connection portion in a direction opposite to the opening portion ,
The wiring module according to claim 3 , wherein the second conductive path is routed from the connection portion between the front surface of the base film and the opposing surface of the connector. The wiring module according to claim 4, wherein the second conductive path is routed from the connection portion toward the opening portion. The wiring module according to claim 5, wherein the second conductive path is bent near the opening of the connector and routed in a direction different from the second direction. The wiring module according to claim 6, wherein a reinforcing plate is provided on the opposite side of the base film from the connector in the first direction. The wiring module according to claim 1 , wherein the protector is provided with a locking portion that locks the second conductive path routed in the recess. A conductive member is connected to the electrode terminal,
The flexible printed circuit board has a land,
The wiring module according to claim 1 , wherein the land is connected to at least one side surface of the conductive member by soldering. The wiring module according to claim 9 , wherein the land is connected to only one side surface of the conductive member by soldering.

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