Battery Module

Abstract

To provide a battery module in which many wirings can be arranged by efficiently using a limited space.SOLUTION: A battery module includes: a plurality of battery cells arranged in a first direction; a plate member provided on a first side of the plurality of battery cells; and a flexible printed circuit board and a control board provided on the plate member. The flexible printed circuit board has wiring which is electrically connected to the control board. At least part of the wiring of the flexible printed circuit board is located in a region overlapping with the control board when viewed from the first side and between the control board and at least one battery cell.SELECTED DRAWING: Figure 5

Description

[Technical field]

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

[0002] A flexible printed circuit board is sometimes used as wiring for a battery module including a plurality of battery cells. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] International Publication No. 2015 / 107583 [Patent Document 2] JP 2019-114464 A Summary of the Invention [Problem to be solved by the invention]

[0004] As the capacity of battery packs increases, the number of battery cells per battery module tends to increase. This also increases the number of wiring that needs to be arranged on the battery module. To deal with this, there is a demand for efficient use of the limited space on the battery module.

[0005] An object of the present technology is to provide a battery module that enables a large amount of wiring to be arranged by efficiently utilizing a limited space. [Means for solving the problem]

[0006] The present technology provides the following battery module.

[0007] [1] A battery module comprising: a plurality of battery cells arranged in a first direction; a plate member provided on a first side of the plurality of battery cells; and a flexible printed circuit board and a control board provided on the plate member, wherein the flexible printed circuit board has wiring electrically connected to the control board, and at least a portion of the wiring of the flexible printed circuit board is positioned between the control board and at least one battery cell in an area that overlaps with the control board when viewed from the first side.

[0008] [2] The battery module described in [1], wherein at least a portion of the wiring of the flexible printed circuit board is positioned between the control board and the plate member in an area that overlaps with the control board when viewed from the first side.

[0009] [3] The battery module according to [1] or [2], wherein the plate member has a protrusion for positioning the flexible printed circuit board.

[0010] [4] A battery module described in any one of [1] to [3], wherein the control board has a connector portion, the flexible printed circuit board has a connection portion, and the connection portion is connected to the connector portion, thereby electrically connecting the flexible printed circuit board and the control board to each other.

[0011] [5] A battery module described in [4], wherein at least a portion of the connector portion or connection portion is located between the control board and at least one battery cell in an area that overlaps with the control board when viewed from the first side.

[0012] [6] The battery module according to any one of [1] to [5], wherein the flexible printed circuit board has a film layer and a conductor portion formed on the film layer and constituting wiring.

[0013] [7] A battery module described in any one of [1] to [6], wherein the wiring includes a first portion located in an area overlapping with the control board when viewed from the first side, a second portion connected to the first portion and located in an area exposed from the control board when viewed from the first side, and a third portion connected to the second portion on the side opposite the first portion and located in the area overlapping with the control board when viewed from the first side.

[0014] [8] The battery module according to any one of [1] to [7], wherein the wiring includes either a voltage detection line or a temperature detection line.

[0015] [9] The battery module described in any one of [1] to [8], wherein the control board has a fastening portion to which a flexible printed circuit board is fastened.

[0016]

[10] The battery module described in [9], wherein the flexible printed circuit board has a recess for avoiding the fastening portion between the control board and the plate member. Effect of the Invention

[0017] According to the present technology, in a battery module, at least a portion of the wiring of a flexible printed circuit board is positioned so as to overlap with a control board when viewed from the height direction of the battery module, thereby enabling a large amount of wiring to be arranged by efficiently utilizing limited space. [Brief description of the drawings]

[0018] [Figure 1] FIG. 2 is a diagram showing a basic configuration of a battery module. [Diagram 2] FIG. 2 is a perspective view showing a battery cell. [Diagram 3] FIG. 2 is a perspective view showing a state in which a wiring module is provided on a battery module. [Figure 4] FIG. 4 is a diagram showing the arrangement of bus bars in a battery pack. [Diagram 5] FIG. 2 is a top view of the battery module. [Figure 6] 6 is a perspective view showing the flexible printed circuit board and the control board shown in FIG. 5. [Figure 7] 11 is a diagram illustrating an example of a positional relationship between a connection portion of a flexible printed circuit board and a connector portion of a control board. FIG. [Figure 8] 13A and 13B are diagrams illustrating modified examples of the positional relationship between a connection portion of a flexible printed circuit board and a connector portion of a control board. [Figure 9] 13A and 13B are top views showing the shape of a flexible printed circuit board according to a modified example. [Figure 10] 13A and 13B are top views showing the shape of a flexible printed circuit board according to another modified example. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0019] Hereinafter, embodiments of the present technology will be described. Note that the same or corresponding parts are denoted by the same reference characters, and description thereof will not be repeated.

[0020] In the embodiments described below, when referring to the number, amount, etc., the scope of the present technology is not necessarily limited to the number, amount, etc., unless otherwise specified. In addition, in the following embodiments, each component is not necessarily essential to the present technology, unless otherwise specified. In addition, the present technology is not necessarily limited to those that achieve all of the effects and advantages mentioned in the present embodiment.

[0021] In this specification, the words "comprise", "include" and "have" are open-ended, i.e., when a certain configuration is included, other configurations may or may not be included.

[0022] Furthermore, when geometric terms and terms expressing positional and directional relationships, such as "parallel," "orthogonal," "45° diagonal," "coaxial," and "along" are used in this specification, these terms allow for manufacturing errors and slight variations. When terms expressing relative positional relationships, such as "upper side" and "lower side," are used in this specification, these terms are used to indicate relative positional relationships in one state, and the relative positional relationships can be inverted or rotated to any angle depending on the installation direction of each mechanism (for example, by turning the entire mechanism upside down).

[0023] In this specification, the term "battery" is not limited to lithium ion batteries, but may include other batteries such as nickel-metal hydride batteries and sodium ion batteries. In this specification, the term "electrode" may collectively refer to positive and negative electrodes. In addition, the term "electrode plate" may collectively refer to positive and negative plates.

[0024] In this specification, a "battery cell" can be mounted in a hybrid electric vehicle (HEV), a plug-in hybrid electric vehicle (PHEV), an electric vehicle (BEV), etc. However, the use of the "battery cell" is not limited to being mounted in a vehicle.

[0025] 1 is a diagram showing the basic configuration of a battery pack 1. As shown in FIG. 1, the battery pack 1 includes a battery cell 100, an end plate 200, and a restraining member 300.

[0026] The multiple battery cells 100 are arranged side by side in the Y-axis direction (first direction). This forms a stack of the battery cells 100. The battery cells 100 include electrode terminals 110. Separators (not shown) are interposed between the multiple battery cells 100. The multiple battery cells 100 sandwiched between the two end plates 200 are pressed by the end plates 200 and are restrained between the two end plates 200.

[0027] The end plates 200 are disposed on both ends of the battery pack 1 in the Y-axis direction. The end plates 200 are fixed to a base such as a case that houses the battery pack 1. The restraining members 300 connect the two end plates 200 to each other.

[0028] By fixing the restraining member 300 to the end plate 200 while a compressive force in the Y-axis direction is applied to the stack of multiple battery cells 100 and end plates 200, and then releasing the compressive force, a tensile force acts on the restraining member 300 connecting the two end plates 200. In reaction to this, the restraining member 300 presses the two end plates 200 in a direction that brings them closer to each other.

[0029] Fig. 2 is a perspective view showing the battery cell 100. As shown in Fig. 2, the battery cell 100 has a rectangular shape. The battery cell 100 has an electrode terminal 110 and a housing 120 (external can). In other words, the battery cell 100 is a rectangular secondary battery cell.

[0030] The electrode terminal 110 is formed on the housing 120. The electrode terminal 110 has a positive electrode terminal 111 and a negative electrode terminal 112 aligned along an X-axis direction (second direction) perpendicular to a Y-axis direction (first direction). The positive electrode terminal 111 and the negative electrode terminal 112 are spaced apart from each other in the X-axis direction.

[0031] The housing 120 has a rectangular parallelepiped shape and forms the external appearance of the battery cell 100. The housing 120 includes a case body 120A that contains an electrode body and an electrolyte (not shown), and a sealing plate 120B that seals an opening of the case body 120A. The sealing plate 120B is joined to the case body 120A by welding.

[0032] The housing 120 has an upper surface 121, a lower surface 122, a first side surface 123, a second side surface 124, and two third side surfaces 125. The housing 120 is provided with a gas exhaust valve 126.

[0033] The upper surface 121 is a plane perpendicular to the Z-axis direction (third direction) perpendicular to the Y-axis direction and the X-axis direction. The electrode terminals 110 are disposed on the upper surface 121. The lower surface 122 faces the upper surface 121 along the Z-axis direction.

[0034] Each of the first side surface 123 and the second side surface 124 is formed of a plane perpendicular to the Y-axis direction. Each of the first side surface 123 and the second side surface 124 has the largest area among the multiple side surfaces of the housing 120. Each of the first side surface 123 and the second side surface 124 has a rectangular shape when viewed in the Y-axis direction. Each of the first side surface 123 and the second side surface 124 has a rectangular shape with the X-axis direction being the long side direction and the Z-axis direction being the short side direction when viewed in the Y-axis direction.

[0035] The multiple battery cells 100 are stacked such that the first side surfaces 123 and the second side surfaces 124 of the battery cells 100 adjacent to each other in the Y-axis direction face each other. As a result, the positive electrode terminals 111 and the negative electrode terminals 112 are arranged alternately in the Y-axis direction in which the multiple battery cells 100 are stacked.

[0036] Gas exhaust valve 126 is provided on top surface 121. When the temperature of battery cell 100 rises (thermal runaway) and the internal pressure of housing 120 exceeds a predetermined value due to gas generated inside housing 120, gas exhaust valve 126 exhausts the gas to the outside of housing 120.

[0037] Fig. 3 is a perspective view showing a state in which a wiring module is provided on the battery pack 1. As shown in Fig. 3, a plate member 400 is placed on the battery pack 1, and a flexible printed circuit board 500 is provided on the plate member 400. The flexible printed circuit board 500 can be electrically connected to an external device via a connector 600. A cover member 700 is provided on the plate member 400 so as to cover the flexible printed circuit board 500.

[0038] Fig. 4 is a diagram showing the arrangement of bus bars 800 in the battery pack 1. In the example of Fig. 4, the positive electrode terminals 111 and negative electrode terminals 112 of adjacent battery cells 100 are electrically connected by the bus bars 800, and the multiple battery cells 100 are electrically connected in series.

[0039] That is, the battery pack 1 includes a plurality of battery cells 100, each having an electrode terminal 110, arranged along a predetermined direction, and a bus bar 800 that connects the electrode terminals 110 of the plurality of battery cells 100 together.

[0040] FIG. 5 is a top view of a battery module. As shown in FIG. 5, the battery module includes a control board 900. In the example of FIG. 5, a part of the flexible printed circuit board 500 (parts A and B in FIG. 5) is located below the control board 900. In other words, a part of the flexible printed circuit board 500 is located between the control board 900 and the battery cell 100 (between the control board 900 and the plate member 400 in the example of FIG. 5) in an area overlapping with the control board 900 when viewed from the upper side (first side) in the Z-axis direction of the battery module. The plate member 400 and the control board 900 each have an opening 400A, 900A above the gas release valve 126 of the battery cell 100. Therefore, blocking of the gas release valve 126 by the plate member 400 and the control board 900 is suppressed.

[0041] Fig. 6 is a perspective view showing the flexible printed circuit board 500 and the control board 900 shown in Fig. 5. Note that the flexible printed circuit board 500 and the control board 900 shown in Fig. 5 and Fig. 6 are merely examples, and the scope of the present technology is not limited thereto.

[0042] 6, the flexible printed circuit board 500 has a connection portion 510 and a tab 520. The control board 900 has a connector portion 910. The connection portion 510 of the flexible printed circuit board 500 is connected to the connector portion 910 of the control board 900, whereby the flexible printed circuit board 500 and the control board 900 are electrically connected to each other. At this time, bending occurs in the flexible printed circuit board 500.

[0043] 6, the flexible printed circuit board 500 includes a main body portion 501 (first portion) and a branch portion 502 (second portion) branched from the main body portion 501. In the example of FIG. 5, the connection portion 510 is provided at the tip of the branch portion 502. The connection portion 510 provided at the branch portion 502 is connected to the control board 900 from the extension direction of the main body portion 501 (the Y-axis direction in the example of FIG. 5). At this time, the branch portion 502 adjacent to the connection portion 510 is flexibly deformed.

[0044] The flexible printed circuit board 500 is composed of a film layer 500A and a conductor portion 500B formed on the film layer 500A. The film layer 500A is composed of an insulating material. The conductor portion 500B is composed of a metal (conductive material) such as copper. The conductor portion 500B constitutes wiring such as a voltage detection line or a temperature detection line.

[0045] The conductor section 500B is also formed in a portion located below the control board 900 (portions A and B in FIG. 5). That is, a portion of the conductor section 500B (portions A and B in FIG. 5) is located below the control board 900. In other words, a portion of the conductor section 500B is located between the control board 900 and the battery cells 100 (between the control board 900 and the plate member 400 in the example of FIG. 6) in a region that overlaps with the control board 900 when viewed from the upper side (first side) in the Z-axis direction of the battery module.

[0046] The conductor portion 500B may extend from the connection portion 510 from a region overlapping with the control substrate 900 through a region not overlapping with the control substrate 900, and then again to a region overlapping with the control substrate 900. For example, in the vicinity of the connection portion 510, the flexible printed circuit board 500 including the conductor portion 500B may be located on the lower side of the control substrate 900 (the region overlapping with the control substrate 900) (first portion of the conductor portion 500B), and in a portion connected to the first portion, the flexible printed circuit board 500 including the conductor portion 500B may be located in a region exposed from the control substrate 900 when viewed from the Z-axis direction (the region not overlapping with the control substrate 900) (second portion of the conductor portion 500B), and in a portion connected to the second portion, the flexible printed circuit board 500 including the conductor portion 500B may be located on the lower side of the control substrate 900 (the region overlapping with the control substrate 900) (third portion of the conductor portion 500B).

[0047] 6, plate member 400 has a protrusion 410. Protrusion 410 includes a first protrusion 411 and a second protrusion 412. Flexible printed circuit board 500 has a hole 530, a notch 540, and a bus bar connection portion 550. Hole 530 includes a long hole 531 and a round hole 532.

[0048] The first protrusion 411 of the plate member 400 penetrates the long hole 531 of the flexible printed circuit board 500, and the second protrusion 412 penetrates the round hole 532. The long hole 531 is formed so that its longitudinal direction is the Y-axis direction. The long hole 531 makes it possible to position the flexible printed circuit board 500 on the plate member 400 while absorbing the dimensional tolerance from the long hole 531 to the round hole 532 in the Y-axis direction and the assembly tolerance between the plate member 400 and the flexible printed circuit board 500.

[0049] Cutout portion 540 is provided between main body portion 501 and branch portion 502 of flexible printed circuit board 500. Cutout portion 540 is formed along the extension direction of main body portion 501 (the Y-axis direction in the example of FIG. 6). Bus bar connection portion 550 is a part of conductor portion 500B, and is provided at the tip of main body portion 501. Bus bar connection portion 550 is connected to bus bar 800.

[0050] 5 and 6, an example has been described in which the battery cell 100, the plate member 400, the flexible printed circuit board 500, and the control board 900 overlap in this order in at least a portion of the area when viewed from the Z-axis direction, but the scope of the present technology is not limited to this. For example, if an opening is provided in the plate member 400 in the above-mentioned portion of the area, the battery cell 100, the flexible printed circuit board 500, and the control board 900 will overlap in this order along the Z-axis direction.

[0051] FIG. 7 is a diagram showing an example of the positional relationship between the connection portion 510 of the flexible printed circuit board 500 and the connector portion 910 of the control board 900. As shown in FIG.

[0052] 7, when the connection portion 510 is not connected to the connector portion 910, i.e., when no bending occurs in the flexible printed circuit board 500, a part of the connection portion 510 of the flexible printed circuit board 500 is located below the control board 900. In other words, a part of the connection portion 510 is located between the control board 900 and the plate member 400 in a region overlapping with the control board 900 when viewed from the upper side (first side) in the Z-axis direction of the battery module. Note that the entire connection portion 510 of the flexible printed circuit board 500 may be located below the control board 900.

[0053] 6 is provided near the connection portion 510 and protrudes from the area overlapping with the control board 900. By pulling the tab 520 in the Y-axis direction, the connection portion 510 can be pulled out from below the control board 900.

[0054] FIG. 8 is a diagram showing a modified example of the positional relationship between the connection portion 510 of the flexible printed circuit board 500 and the connector portion 910 of the control board 900. In FIG.

[0055] 8, the connector unit 910 is located below the control board 900. In other words, the connector unit 910 is located between the control board 900 and the plate member 400 in a region overlapping with the control board 900 when viewed from the upper side (first side) in the Z-axis direction of the battery module. As a further modified example, only a portion of the connector unit 910 may be located below the control board 900.

[0056] In this way, by disposing at least a part of the connector section 910 below the control board 900, the height of the battery module can be reduced.

[0057] 9 and 10 are top views showing the shape of a flexible printed circuit board 500 according to a modified example.

[0058] 9 and 10, the control board 900 has a fastening portion 920 with the plate member 400. The flexible printed circuit board 500 reaches further into the control board 900 than the fastening portion 920. The flexible printed circuit board 500 has a relief portion 560 that avoids the fastening portion 920. This makes it possible to increase the region (area) of the flexible printed circuit board 500 while avoiding interference with the fastening portion 920.

[0059] The relief portion 560 may be configured by a recess as in the example of FIG. 9, or may be configured by a hole as in the example of FIG.

[0060] According to this embodiment, at least a portion of the conductor portion 500B (wiring) of the flexible printed circuit board 500 is positioned so as to overlap with the control board 900 when viewed from the Z-axis direction, thereby making it possible to efficiently utilize the limited space on the battery module and arrange many conductor portions 500B.

[0061] Although the embodiment of the present technology has been described above, the embodiment disclosed herein should be considered as illustrative and not restrictive in all respects. The scope of the present technology is defined by the claims, and it is intended to include all modifications within the scope and meaning equivalent to the claims. [Explanation of symbols]

[0062] 1 battery pack, 100 battery cell, 110 electrode terminal, 111 positive electrode terminal, 112 negative electrode terminal, 120 housing, 120A case body, 120B sealing plate, 121 upper surface, 122 lower surface, 123 first side, 124 second side, 125 third side, 126 gas exhaust valve, 200 end plate, 300 restraining member, 400 plate member, 400A opening, 410 protrusion, 411 first protrusion, 412 second protrusion, 500 flexible printed circuit board, 500A film layer, 500B conductor portion, 501 main body portion, 502 branch portion, 510 connection portion, 520 tab, 530 hole portion, 531 long hole, 532 round hole, 540 notch portion, 550 bus bar connection portion, 560 Recess portion, 600 connector, 700 cover member, 800 bus bar, 900 control board, 900A opening, 910 connector portion, 920 fastening portion.

Claims

1. A plurality of battery cells arranged in a first direction; a plate member provided on a first side of the plurality of battery cells; a flexible printed circuit board and a control board provided on the plate member, the flexible printed circuit board has wiring electrically connected to the control board, at least a portion of the wiring of the flexible printed circuit board is located between the control board and at least one of the battery cells in a region overlapping with the control board when viewed from the first side; The wiring is a first portion located in a region overlapping with the control board when viewed from the first side; a second portion connected to the first portion and located in an area exposed from the control board when viewed from the first side; a third portion connected to the second portion on an opposite side to the first portion and located in a region overlapping with the control board when viewed from the first side.

2. The battery module according to claim 1 , wherein at least a portion of the wiring of the flexible printed circuit board is located between the control board and the plate member in a region overlapping the control board when viewed from the first side.

3. 3. The battery module according to claim 1, wherein the plate member has a protrusion for positioning the flexible printed circuit board.

4. The control board has a connector portion, 3. The battery module according to claim 1, wherein the flexible printed circuit board has a connection portion, and the connection portion is connected to the connector portion, thereby electrically connecting the flexible printed circuit board and the control board to each other.

5. The battery module according to claim 4 , wherein at least a portion of the connector portion or the connection portion is located between the control board and at least one of the battery cells in a region overlapping the control board when viewed from the first side.

6. 3. The battery module according to claim 1, wherein the flexible printed circuit board has a film layer and a conductor portion formed on the film layer and constituting the wiring.

7. The battery module according to claim 1 , wherein the wiring includes either a voltage detection line or a temperature detection line.

8. The battery module according to claim 1 , wherein the control board has a fastening portion to which the flexible printed circuit board is fastened.

9. The battery module according to claim 8 , wherein the flexible printed circuit board has a recess for avoiding the fastening portion.

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