Battery wiring module

Provided is a battery wiring module that can hold busbars until they are connected to a secondary battery. A busbar is configured to connect battery terminals of a plurality of battery cells to each other, and has a recess portion that is recessed in a Z direction, which is a stack direction in which a housing is stacked on the battery cells. The battery wiring module includes a busbar holding portion configured to be inserted into the recess portions, and engage with the busbar in an X direction, which is a direction in which the battery cells are lined up, so as to hold the busbar.

TECHNICAL FIELD

The present invention relates to a battery wiring module.

BACKGROUND ART

As disclosed in JP 2013-37988A for example, in vehicles such as electric automobiles and hybrid automobiles, a high-voltage secondary battery, which is installed as a power supply for driving the vehicle when the vehicle is traveling, is provided with a battery wiring module. In the battery wiring module, a module-side terminal is connected to a busbar (a connecting member in JP 2013-37988A1) that connects a plurality of battery cells constituting the secondary battery to each other.

JP 2013-37988A is an example of related art.

SUMMARY OF THE INVENTION

Meanwhile, in the battery wiring modules as described above, it is conceivable that, for example, the busbar and the module-side terminal that are housed in a housing are connected to the secondary battery, or the module-side terminal that is housed in the housing is connected to the busbar connected to the secondary battery. However, for example, a case has not been considered in which the module-side terminal is housed in the housing, and then the busbar is attached to the housing. In this case, for example, the busbar needs to be held until it is connected to the secondary battery, but such a battery wiring module has not been developed.

The present invention was made to solve the aforementioned problem, and it is an object thereof to provide a battery wiring module that can hold a busbar until it is connected to a secondary battery.

Solution to Problem

In order to solve the aforementioned problem, a battery wiring module includes: a module-side terminal configured to be electrically connected to a busbar for connecting battery terminals of a plurality of battery cells to each other; a wire that has one end to which the module-side terminal is connected; and a housing in which the wire and the module-side terminal are housed, wherein the busbar is configured to connect the battery terminals of the plurality of battery cells to each other, and has a recess portion that is recessed in a stack direction in which the housing is stacked on the battery cells, and the battery wiring module further includes a busbar holding portion configured to be inserted into the recess portion, and engage with the busbar in a direction in which the battery cells are lined up, so as to hold the busbar.

According to the above-described aspect, as a result of including the busbar holding portion configured to be inserted into the recess portion, and engage with the busbar in the direction in which the battery cells are lined up, so as to hold the busbar, the battery wiring module can hold the busbar until it is connected to the secondary battery.

In the above-described battery wiring module, preferably, the busbar holding portion includes an elastic piece configured to apply an elastic force in the direction in which the battery cells are lined up.

According to the above-described aspect, as a result of the busbar holding portion including the elastic piece configured to apply an elastic force in the direction in which the battery cells are lined up, even when the busbar moves due to expansion or contraction of the battery cells, the elastic piece is bent to allow the busbar to move.

In the above-described battery wiring module, preferably, elastic pieces are provided on two sides in the direction in which the battery cells are lined up.

According to the above-described aspect, as a result of the elastic pieces being provided on two sides in the direction in which the battery cells are lined up, even when the busbar moves due to expansion or contraction of the battery cells, the elastic pieces are bent to allow the busbar to move.

In the above-described battery wiring module, preferably, the housing is provided with a movement restricting rib configured to restrict, together with the busbar holding portion, movement of the busbar in the stack direction.

According to the above-described aspect, as a result of the housing being provided with the movement restricting rib configured to restrict, together with the busbar holding portion, movement of the busbar in the stack direction, it is possible to restrict movement of the busbar in the stack direction.

Advantageous Effects of Invention

According to the battery wiring module of the present invention, it is possible to hold a busbar until it is connected to a secondary battery.

EMBODIMENTS OF THE INVENTION

Hereinafter, an embodiment of a battery wiring module will be described. Note that, in the drawings, part of a configuration may be exaggerated or simplified, for ease of description. Furthermore, dimensions of constituent components may be scaled differently from the actual ones.

As shown inFIG. 1, a battery wiring module10is mounted on the upper surface of a substantially cuboid secondary battery BT. Note that the secondary battery BT is installed in an electric automobile, a hybrid automobile, or the like, and supplies electric power to a vehicle traveling motor. Furthermore, the secondary battery BT is supplied with electric power from the traveling motor or a power generation motor depending on charge conditions or vehicle driving conditions. Here, in the following, description will be made assuming that, out of three directions X, Y, and Z inFIG. 1that are orthogonal to each other, the X direction is a direction in which battery cells are lined up, the Y direction is a width direction of the battery wiring module, and the Z direction is a vertical direction.

The secondary battery BT includes a plurality of battery cells C, and not-shown positive and negative electrodes of the battery cells C are arranged on the battery wiring module10side (upper side).

The plurality of battery cells C are lined up in the X direction. At this time, the battery cells C are lined up such that their positive and negative electrodes, which serve as battery terminals, are alternately arranged in the direction in which the battery cells C are lined up, that is, in the X direction. Busbars B are provided for these terminals, each busbar being configured to connect adjacent terminals, that is, a positive electrode and a negative electrode, to each other. In other words, the battery cells C are connected in series by the busbars B. The busbars B of the present embodiment are connected to the positive electrodes and the negative electrodes of the battery cells C by welding, for example.

As shown inFIG. 1, the battery wiring module10includes a housing11, a plurality of module-side terminals12, and a plurality of wires13(seeFIG. 4).

The housing11has a shape such that, for example, the size in the X direction, which is the direction in which the battery cells C are lined up, is greater than the size in the Y direction, which is the width direction. The upper side of the housing11is open, and the opening is designed to be closed by a not-shown cover.

The housing11is made of, for example, a resin member. The housing11includes wire accommodating portions20in each of which a wire is accommodated, and terminal accommodating portions30in each of which a module-side terminal12is accommodated.

As shown inFIG. 4, each module-side terminal12has a flat plate-shaped terminal body12a, and a barrel portion12bthat is contiguous from the terminal body12a. The barrel portion12bis electrically connected to the core wire of a wire13.

As shown inFIGS. 1 to 4, the wire accommodating portions20of the housing11are compartments of the housing11that are formed by a bottom portion21and a side wall22that extends from the outer edge portion of the bottom portion21. The wire accommodating portions20include a plurality of recess portions23and24arranged in the direction in which the plurality of battery cells C are lined up, the plurality of recess portions23and24being recessed in the direction that is orthogonal to the direction in which the plurality of battery cells C are lined up, and is orthogonal to a stack direction in which the housing11is stacked on the battery cells C, that is, the plurality of recess portions23and24being recessed in the width direction Y. Each recess portion23receives one terminal accommodating portion30. Each recess portion24receives two terminal accommodating portions30.

As shown inFIGS. 1 to 4, the terminal accommodating portions30of the housing11are compartments of the housing11that are formed by a bottom portion31and a side wall32that extends from the outer edge portion of the bottom portion31. The terminal accommodating portions30are substantially cuboid shaped with a long length in the X direction. There is a gap S1between a terminal accommodating portion30and a recess portion23of the corresponding wire accommodating portion20, the gap S1being provided on two sides, in the X direction, of the terminal accommodating portion30and on one side, in the Y direction, thereof. Furthermore, the side wall32of the terminal accommodating portion30has an opening33that is open in the X direction (to the wire accommodating portion20side), and an opening34that is open in the Y direction, which is orthogonal to X direction.

As shown inFIGS. 2 and 3, the opening33that is open in the X direction of the terminal accommodating portion30faces, in the X direction, an opening22aformed in the side wall22of the corresponding wire accommodating portion20. Accordingly, the opening33of the terminal accommodating portion30and the opening22aof the wire accommodating portion20can be used to guide the wire13connected to the module-side terminal12accommodated in the terminal accommodating portion30into the wire accommodating portion20. In other words, the opening33of the terminal accommodating portion30and the opening22aof the wire accommodating portion20function as openings for guiding (inserting) the wire13.

As shown inFIGS. 2 and 3, the opening34is open outward in the Y direction (to the side opposite to the wire accommodating portion20). The opening34allows part of the terminal body12aof the module-side terminal12accommodated in the terminal accommodating portion30to be exposed to the outside in the Y direction. The part of the terminal body12athat is exposed from the opening34is electrically connected to the busbar B.

As shown inFIGS. 1 and 2, the busbars B used in the present embodiment are made of a conductive plate material. Each busbar B has two connection plates B1that are respectively connected to a positive electrode and a negative electrode of adjacent battery cells C. Furthermore, each busbar B of the present embodiment has, between the connection plates B1, a recess portion B2that is recessed in the plate-thickness direction (Z direction) of the connection plates B1. The recess portion B2is recessed in the direction (upward direction) away from the secondary battery BT in the Z direction.

As shown inFIGS. 1 to 4, the housing11is provided with busbar holding portions40that extend outward in the width direction from the side walls22and32on two sides in the width direction (two sides in the Y direction).

As shown inFIGS. 2 to 4, each busbar holding portion40includes two elastic pieces41on two sides in the X direction. Each elastic piece41is plate-shaped facing the X direction, and is likely to bend in the X direction. The distance, in the X direction, between the two elastic pieces41is set to be substantially the same as the length, in the X direction, of the recess portion B2of the busbar B. Accordingly, the two elastic pieces41are provided with projections42that protrude outward in the X direction in a state in which the busbar holding portion40is inserted into the busbar B (recess portion B2).

The projections42can engage with (abut against) the busbar B in the Y direction in a state in which the busbar B is attached to the busbar holding portion40. Accordingly, the busbar B is prevented from disengaging from the busbar holding portion40in the Y direction.

Furthermore, the housing11includes restricting ribs50on the side, in the X direction, of the busbar holding portions40that is opposite to the module-side terminals12, the restricting ribs50extending in the width direction. Each restricting rib50sandwiches, together with a busbar holding portion40, a busbar B in the vertical direction when the busbar B is attached to the busbar holding portion40. More specifically, the restricting rib50is located above the busbar B in the Z direction, which is the vertical direction, and the busbar holding portion40is located below the busbar B in the Z direction, which is the vertical direction. Accordingly, movement of the busbar B in the Z direction is restricted. Here, for example, by using the terminal accommodating portion30of the module-side terminal12to restrict movement in the Z direction, it is possible to restrict the movement of the busbar B in the Z direction with the use of the module-side terminal12.

The following will describe functions of the present embodiment.

The battery wiring module10of the present embodiment is arranged on the secondary battery BT that includes the plurality of battery cells C. The module-side terminals12of the battery wiring module10are connected to the busbars B that connect the positive and negative electrodes of the battery cells C lined up in the X direction. One end of a wire13is connected to a module-side terminal12, and the other end (not-shown) of the wire13is connected to a not-shown battery monitoring ECU. The battery monitoring ECU can monitor voltages of the battery cells C.

In the battery wiring module10of the present embodiment, the busbars B are held by the busbar holding portions40until the busbars B are connected (for example, welded) to the secondary battery BT. At this time, while being inserted into the recess portions B2of the busbars B, the busbar holding portions40are configured to engage with, using the elastic pieces41, the busbars B in the X direction.

The following will describe effects of the present embodiment.

(1) As a result of including the busbar holding portions40configured to be inserted into the recess portions B2, and engage with the busbars B in the direction in which the battery cells C are lined up, so as to hold the busbars B, the battery wiring module can hold the busbars B until they are connected to the secondary battery BT.

(2) As a result of the busbar holding portions40including an elastic piece41configured to apply an elastic force in the direction in which the battery cells C are lined up, even when the busbars B move due to expansion or contraction of the battery cells C, the elastic piece is bent to allow the busbars B to move.

(3) As a result of the elastic pieces41being provided on two sides in the direction in which the battery cells C are lined up, even when the busbars B move due to expansion or contraction of the battery cells C, the elastic pieces are bent to allow the busbars B to move.

(4) As a result of the housing11being provided with the restricting ribs50configured to restrict, together with the busbar holding portions40, movement of the busbars B in the stack direction, it is possible to restrict movement of the busbars B in the stack direction.

Note that the above-described embodiment can be modified and implemented in the following manner. The above-described embodiment and the following modifications can be implemented in a suitable combination without technically contradicting each other.The above-described embodiment employs a configuration in which the restricting ribs50are provided, but may also employ a configuration without the restricting ribs50. Furthermore, the shape of the restricting ribs50is not limited to the disclosed content, and may be modified as appropriate as long as they are configured to sandwich, together with the busbar holding portions40, the busbars B in the vertical direction (Z direction).The above-described embodiment employs a configuration in which the elastic pieces41are provided on two sides in the left-right direction, but may also employ a configuration in which an elastic piece41is provided on only one side in the left-right direction. Furthermore, a configuration without the elastic piece41may also be employed.

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