Voltage Monitoring Module

Abstract

To provide a voltage monitoring module with a structure capable of improving the positional accuracy of a metal plate with respect to a land.SOLUTION: A voltage monitoring module 100 includes a flexible printed board 10 having a plurality of wirings 17 and a plurality of lands 16 to which one ends of the wirings 17 are respectively connected, and a plurality of metal plates 20 arranged over the land 16 and soldered to the land 16, and a through hole 24 is formed in a portion of the metal plate 20 corresponding to the land 16, and a portion of the land 16 corresponding to the through hole 24 is a non-formation region 18 in which no conductor is formed.SELECTED DRAWING: Figure 4

Description

[Technical field]

[0001] The present invention relates to a voltage monitoring module. [Background technology]

[0002] Patent Document 1 describes a printed circuit board having a structure in which a notch-shaped portion is formed in a metal plate that is soldered to a land. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2002-111170 A Summary of the Invention [Problem to be solved by the invention]

[0004] According to the investigations of the present inventors, the technique of Patent Document 1 has room for improvement in terms of the positional accuracy of the metal plate relative to the lands.

[0005] The present invention has been made in consideration of the above-mentioned problems, and provides a voltage monitoring module having a structure that enables the positional accuracy of a metal plate relative to a land to be improved. [Means for solving the problem]

[0006] According to the present invention, there is provided a flexible printed circuit board having a plurality of wirings and a plurality of lands each having one end connected to the wirings; a plurality of metal plates disposed on the lands and soldered to the lands; Equipped with a through hole is formed in a part of the metal plate corresponding to the land, In the land, a portion corresponding to a part of the through hole is a non-forming region where no conductor is formed. And, When viewed in the thickness direction of the metal plate, an area of ​​the through hole is larger than an area of ​​the non-forming region, and an outline of the non-forming region is entirely disposed at a position spaced apart from the inside of an inner periphery of the through hole.A voltage monitoring module is provided. Effect of the Invention

[0007] According to the present invention, it is possible to improve the positional accuracy of the metal plate with respect to the land. [Brief description of the drawings]

[0008] [Figure 1] 1 is a plan view showing a voltage monitoring module according to an embodiment and a plurality of battery cells connected to the voltage monitoring module; [Diagram 2] 1 is a perspective view of a voltage monitoring module according to an embodiment; [Diagram 3] 2 is a partially enlarged plan view of the voltage monitoring module according to the first embodiment; FIG. [Figure 4] FIG. 4(a) is a partially enlarged plan view of the voltage monitoring module according to the first embodiment, and FIG. 4(b) is a cross-sectional view taken along line AA in FIG. 4(a). [Diagram 5] FIG. 5(a) is a partially enlarged plan view of the voltage monitoring module according to the first embodiment, and FIG. 5(b) is a cross-sectional view taken along line AA in FIG. 5(a). [Figure 6] FIG. 11 is a partially enlarged plan view of a voltage monitoring module according to a second embodiment. [Figure 7] Figure 7(a) is a plan view of the end of an extension portion of a flexible printed circuit board provided in a voltage monitoring module according to the second embodiment, Figure 7(b) is a plan view of a metal plate of the voltage monitoring module according to the second embodiment, and Figure 7(c) is a partially enlarged plan view of the voltage monitoring module according to the second embodiment. [Figure 8] FIG. 11 is a partially enlarged plan view of a voltage monitoring module according to a third embodiment. [Figure 9]9(a) is a plan view of the end of an extension portion of a flexible printed circuit board provided in a voltage monitoring module according to the third embodiment, FIG. 9(b) is a plan view of a metal plate of the voltage monitoring module according to the third embodiment, FIG. 9(c) is an enlarged plan view of a portion of the voltage monitoring module according to the third embodiment, FIG. 9(d) is a cross-sectional end view taken along line AA in FIG. 9(c), and FIG. 9(e) is a cross-sectional end view taken along line BB in FIG. 9(c). [Figure 10] FIG. 10(a) is a partially enlarged plan view of a voltage monitoring module according to the third embodiment, and FIG. 10(b) is a cross-sectional view taken along line AA in FIG. 10(a). [Figure 11] FIG. 13 is a partially enlarged plan view of a voltage monitoring module according to a fourth embodiment. [Figure 12] Figure 12(a) is a plan view of the end of an extension portion of a flexible printed circuit board provided in a voltage monitoring module according to the fourth embodiment, Figure 12(b) is a plan view of a metal plate of the voltage monitoring module according to the fourth embodiment, Figure 12(c) is an enlarged plan view of a portion of the voltage monitoring module according to the fourth embodiment, and Figure 12(d) is a cross-sectional end view taken along line AA in Figure 12(c). [Figure 13] FIG. 13 is a plan view of a voltage monitoring module according to a fifth embodiment. [Figure 14] FIG. 13 is a partially enlarged plan view of a voltage monitoring module according to a comparative example. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0009] Hereinafter, an embodiment of the present invention will be described with reference to the drawings. In all the drawings, the same components are denoted by the same reference numerals, and the description thereof will be omitted as appropriate.

[0010] [First embodiment] First, the first embodiment will be described with reference to FIG. 1 to FIG. 5(b). It should be noted that fixing members that fix the metal plate 20 to the battery cell 70 are not shown in Fig. 1. Fig. 3 shows an enlarged view of one metal plate 20 and the area corresponding to an end 15 of one extension portion 12 corresponding to the metal plate 20. Figs. 4(a) and 5(a) show an enlarged view of the area corresponding to one end 15. Wiring 17 is not shown in Figs. 4(a) and 5(a).

[0011] The voltage monitoring module 100 of this embodiment comprises a flexible printed circuit board 10 (FIGS. 1 and 2) having a plurality of wirings 17 (FIG. 3) and a plurality of lands 16 (FIGS. 3 to 5(b)) to which one end of each of the wirings 17 is connected, and a plurality of metal plates 20 arranged on top of the lands 16 and solder-joined to the lands 16. In the metal plate 20, a through hole 24 (FIGS. 3 to 5(b)) is formed in a part of the area corresponding to the land 16. In the land 16, a portion corresponding to a part of the through hole 24 is a non-formation region 18 (FIGS. 3 to 5(b)) where no conductor is formed. In the present invention, the metal plate 20 may be a bus bar or a metal tab connected to a bus bar. In this embodiment, an example in which the metal plate 20 is a bus bar will be described.

[0012] According to this embodiment, a through hole 24 is formed in a portion of the metal plate 20 that corresponds to the land 16, so that voids contained in the molten solder 30 can escape through the through hole 24, making it possible to suppress the remaining of voids in the solder 30. Moreover, the land 16 has a portion corresponding to a part of the through hole 24 of the metal plate 20 as a non-forming region 18 where no conductor is formed. This allows the positional accuracy of the metal plate 20 with respect to the land 16 to be naturally well controlled by the surface tension of the molten solder when soldering the metal plate 20 to the land 16. This is expected to eliminate the need to use a jig to hold the metal plate 20 in order to maintain the positional accuracy of the metal plate 20. Furthermore, since the non-forming area 18 is disposed in a position corresponding to the through hole 24, a fillet 31 (FIGS. 4(a) and 4(b)) of the solder 30 can be formed in the area inside the through hole 24. Therefore, even if the dimensions of the land 16 are set so that it is covered by the metal plate 20, the appearance of the fillet 31 can be easily inspected using an image inspection device. Note that the appearance inspection of the fillet 31 may be performed not only by the image inspection device, but also by visual inspection by an inspector or by inspection using an X-ray inspection machine. In addition, since the non-formation region 18 is disposed in a position corresponding to the through hole 24, the flux used in soldering can flow into the non-formation region 18, which prevents the flux from accumulating thickly in the through hole 24. This improves the visibility of the fillet 31 (FIG. 4(b)) of the solder 30, making it possible to more easily and reliably perform a visual inspection of the fillet 31, thereby improving the reliability of the visual inspection. Furthermore, since the fillet 31 can be formed along the inner circumference of the through hole 24 and the total length of the fillet 31 can be sufficiently ensured, the bonding strength between the land 16 and the metal plate 20 can also be sufficiently ensured.

[0013] This embodiment will be described in more detail below. As shown in FIGS. 1 and 2, a flexible printed circuit board 10 includes a flat body portion 11 and a plurality of extension portions 12 extending from edges of the body portion 11. The shape of the extension portion 12 is not particularly limited, but as an example, as shown in FIG. 2, the extension portion 12 is formed in a bent shape and has an end portion 15 at the tip of the extension portion 12. End 15 is formed, for example, to be wider than a portion of extension 12 on the base end side of end 15. As one example, extension 12 is entirely disposed on the same plane. The planar shape of end 15 is not particularly limited, but as one example, it is rectangular (for example, rectangular with three rounded corners).

[0014] As shown in FIG. 3, at the end portion 15, a land 16 which is a thin film of a conductor such as a metal is formed. The planar shape of the land 16 is not particularly limited, but is, for example, rectangular (for example, rectangular with rounded corners). The flexible printed circuit board 10 includes a plurality of wirings 17 each extending from the main body 11 to an end 15 of each extension 12. For example, one wiring 17 is disposed for each extension 12. One land 16 is formed on each end 15, and the tip of each wiring 17 is connected to the corresponding land 16.

[0015] As described above, a portion of the land 16 is the non-forming region 18 where no conductor is formed. Since no conductor is present in the non-forming region 18, adhesion of the solder 30 is suppressed. The non-forming regions 18 are arranged in an island shape inside the outline of the land 16 . The planar shape of the non-forming region 18 is not particularly limited, but in this embodiment, for example, it is a rectangle that is elongated in one direction. However, in the present invention, the shape of the non-forming region 18 may be a circle, a polygonal shape other than a rectangle, or other shapes. The number of non-forming regions 18 arranged in each land 16 is not particularly limited, but in this embodiment, one non-forming region 18 is arranged in each land 16.

[0016] The metal plate 20 is formed, for example, in a flat plate shape. The metal plate 20 has, for example, a main body 21 and a protruding portion 22 having a width dimension smaller than that of the main body 21 and protruding from the main body 21. The planar shape of the main body 21 is not particularly limited, but is, for example, rectangular (for example, rectangular with rounded corners). The planar shape of the protruding portion 22 is not particularly limited, but is, for example, rectangular (for example, rectangular with rounded two corners on the tip side in the protruding direction). Here, the flexible printed circuit board 10 is used to monitor voltage, for example, by connecting wiring 17 to a bus bar that connects multiple battery cells 70. That is, in this embodiment, the metal plate 20 is a bus bar that connects multiple battery cells 70 in series. In this embodiment, the voltage monitoring module 100 includes the flexible printed circuit board 10 and multiple metal plates 20, and these metal plates 20 connect the multiple battery cells 70 in series. The battery cell 70 is a secondary battery. The flexible printed circuit board 10 is, for example, equipped with a connector, and is connected via the connector to a measuring device that performs various controls, enabling voltage monitoring.

[0017] The main body 21 of the metal plate 20 has two fixing holes 23 for fixing and electrically connecting the main body 21 to each of the two battery cells 70 arranged adjacent to each other. Note that, when the metal plate 20 is a metal tab that is connected to a bus bar, the metal plate 20 does not have the fixing holes 23, and the bus bar has the fixing holes 23. On the other hand, the above-mentioned through hole 24 is formed in the protruding portion 22. The through hole 24 penetrates the metal plate 20 (the protruding portion 22) in the thickness direction. The number of through holes 24 that each metal plate 20 has is not particularly limited, but in this embodiment, one through hole 24 is formed in each metal plate 20 (in each protruding portion 22). The planar shape of the through hole 24 is not particularly limited, but in this embodiment, for example, it is a rectangle that is elongated in one direction. However, in the present invention, the shape of the through hole 24 may be a circle, a polygonal shape other than a rectangle, or other shapes. In this embodiment, the area of ​​the through-hole 24 is larger than the area of ​​the non-forming region 18 .

[0018] As shown in FIGS. 4( a ) to 5 ( b ), the protruding portion 22 of the metal plate 20 is joined to the corresponding land 16 of each extension portion 12 via solder 30 . In this embodiment, the area of ​​the land 16 is smaller than the area of ​​the protruding portion 22, and as shown in Figures 3 and 4(a), when viewed in the thickness direction of the metal plate 20, the land 16 is contained inside the outline of the metal plate 20 (more specifically, the land 16 is contained inside the outline of the protruding portion 22 of the metal plate 20). This makes it possible to reduce the size of the land 16 and therefore the end portion 15 of the extending portion 12, and also reduces the space and layout constraints of each portion of the flexible printed circuit board 10.

[0019] Furthermore, in the case of this embodiment, when viewed in the thickness direction of the metal plate 20, the non-formed region 18 is contained inside the through hole 24. Therefore, when the solder 30 is viewed from the back surface side, the fillet 31 is formed along the entire inner circumference of the through hole 24, making it easier to confirm the fillet 31. For example, as shown in FIG. 4( a ) and the like, the longitudinal direction of the through-hole 24 and the longitudinal direction of the non-forming region 18 coincide with each other, and the non-forming region 18 is disposed in the center of the through-hole 24 .

[0020] In the case of this embodiment, since the through holes 24 and the non-forming regions 18 are each rectangular, the condition that at least one of the through holes 24 and the non-forming regions 18 is noncircular is satisfied. This makes it possible to more reliably obtain the effect of automatically and satisfactorily controlling the positional accuracy of the metal plate 20 with respect to the lands 16 by the surface tension of the molten solder as described above.

[0021] 5(b), a fillet 32 ​​is formed on the surface of the protruding portion 22 facing the end portion 15, for example, along the outer periphery of the land 16. The fillet 32 ​​has an upside-down shape compared to the fillet 31. Depending on the amount of solder 30, the fillet 32 ​​does not necessarily have to be formed along the entire outer periphery of the land 16, but may be selectively formed along a portion of the outer periphery of the land 16, or the fillet 32 ​​may not be substantially formed.

[0022] Here, FIG. 14 is a partially enlarged plan view of a voltage monitoring module according to a comparative example. The voltage monitoring module according to the comparative embodiment includes, for example, a flexible printed circuit board having an extension 212, and a metal plate 220. The flexible printed circuit board has a wiring 217, and an end of the wiring 217 is connected to a land 216. The land 216 is disposed at an end 215 of the extension 212. For example, two through holes (through hole 224 and through hole 225) are formed in protruding portion 222 of metal plate 220. Of these, through hole 224 entirely overlaps with land 216. Meanwhile, a portion of through hole 225 overlaps with land 216, but the remaining portion of through hole 225 does not overlap with land 216. The land 216 of the voltage monitoring module according to the comparative example does not have a structure corresponding to the non-forming region 18 . In contrast, the voltage monitoring module 100 of this embodiment has a non-formation area 18 formed on the land 16, and therefore this embodiment is more effective at suppressing misalignment between the land 16 and the metal plate 20 than the voltage monitoring module of the comparative embodiment.

[0023] Second Embodiment Next, a second embodiment will be described with reference to FIG. 6 to FIG. 6 shows an enlarged view of one metal plate 20 and an area corresponding to an end 15 of one extension portion 12 corresponding to the metal plate 20. Fig. 7(a) shows an enlarged view of the area corresponding to one end 15. Fig. 7(b) shows an enlarged view of the area corresponding to one protrusion 22. Wiring 17 is omitted in Figs. 7(a) and 7(c). The voltage monitoring module 100 of this embodiment differs from the voltage monitoring module 100 of the first embodiment described above in the points described below, but in other respects is configured in the same way as the voltage monitoring module 100 of the first embodiment described above.

[0024] As shown in any one of Figures 6 to 7(c), in this embodiment, a plurality of through holes 24 are formed in the protruding portion 22 of each metal plate 20, and a plurality of non-forming areas 18 are arranged in the land 16 at the end 15 of each extension portion 12, which correspond one-to-one to the plurality of through holes 24 of the corresponding metal plate 20. That is, a plurality of through holes 24 are formed in one metal plate 20, and a plurality of non-formation areas 18 exist in one land 16. This makes it possible to more reliably prevent the metal plate 20 from rotating relative to the land 16 (rotation in the in-plane direction of the metal plate 20) when soldering the metal plate 20 to the land 16, thereby improving the positional accuracy of the metal plate 20 relative to the land 16.

[0025] The shapes of the through holes 24 and the non-forming regions 18 in this embodiment are not particularly limited, but are, for example, circular, and the diameter of each through hole 24 is larger than the diameter of the corresponding non-forming region 18. When viewed in the thickness direction of the metal plate 20, each non-forming region 18 is contained inside the corresponding through hole 24. The number of through holes 24 in each metal plate 20 and the number of non-forming areas 18 in each land 16 may be two or three or more, but in this embodiment, they are, for example, two. The arrangement of the multiple through holes 24 is not particularly limited, but for example, the multiple through holes 24 are arranged at different positions from each other in the protruding direction of the protrusion 22 (the downward direction in Figures 7(b) and 7(c)). Similarly, the arrangement of the non-forming regions 18 is not particularly limited, but the non-forming regions 18 are arranged at different positions in the protruding direction (the downward direction in FIG. 7(c)) of the protruding portion 22. In other words, the non-forming regions 18 are arranged at different positions in the width direction of the end portion 15 (the vertical direction in FIGS. 7(a) and 7(c)).

[0026] Third Embodiment Next, a third embodiment will be described with reference to FIG. 8 to FIG. 10(b). 8 shows an enlarged view of one metal plate 20 and an area corresponding to an end 15 of one extension portion 12 corresponding to the metal plate 20. Fig. 9(a) shows an enlarged view of the area corresponding to one end 15. Fig. 9(b) shows an enlarged view of the area corresponding to one protrusion 22. Wiring 17 is omitted from Fig. 9(a) and Fig. 9(c). The voltage monitoring module 100 of this embodiment differs from the voltage monitoring module 100 of the first embodiment described above in the points described below, but in other respects is configured in the same way as the voltage monitoring module 100 of the first embodiment described above.

[0027] As shown in FIGS. 8 and 9(c), in this embodiment, a portion of the non-forming region 18 protrudes from the through hole 24 when viewed in the thickness direction of the metal plate 20. Such a structure is effective in cases where there is a restriction on the size of the through hole 24. For example, this applies to cases where the area of ​​the metal plate 20 (e.g., the area of ​​the protruding portion 22) is small and it is difficult to form the through hole 24 of a size that encompasses the non-forming region 18 without deforming the metal plate 20, or cases where there are restrictions on specifications and design.

[0028] More specifically, in this embodiment, among the directions along the plate surface of the metal plate 20, the dimension of the through hole 24 in a first direction (left-right direction in Figures 9(a) to (c)) is larger than the dimension of the non-forming area 18, and the dimension of the non-forming area 18 in a second direction perpendicular to the first direction (up-down direction in Figures 9(a) to (c)) is larger than the dimension of the through hole 24. 9(c), for example, in the first direction, the non-formation region 18 is disposed in the center of the through hole 24, and in the second direction, the through hole 24 is disposed in the center of the non-formation region 18. In other words, the non-formation region 18 protrudes from the through hole 24 in one direction and in the opposite direction in the second direction. For this reason, the fillet 31 is divided into two in the range visible through the through hole 24. That is, in Fig. 9(c) and Fig. 9(d), there is a fillet 31 located on the left side of the non-forming region 18 and a fillet 31 located on the right side of the non-forming region 18.

[0029] When a fillet 31 is formed that is divided into two parts (divided into two in the first direction) with a non-forming area 18 in between as in this embodiment, if the metal plate 20 is misaligned in the first direction with respect to the land 16 as shown in Figure 10(a), a fillet 31 of sufficient size is formed on one side of the non-forming area 18 (for example, the right side in Figures 10(a) and 10(b)), making it possible to reliably recognize the fillet 31 by inspection.

[0030] In this embodiment, the through-hole 24 is formed in an elliptical shape that is long in the first direction, as shown in FIG. 9(b), for example. On the other hand, as shown in FIG. 9(a), the non-forming region 18 is formed in a shape resembling, for example, a sideways H-shape. In this case, if the amount of solder 30 is sufficiently large, each fillet 31 will be, for example, crescent-shaped, and if the amount of solder 30 is small, each fillet 31 will be, for example, semi-arc-shaped. In the case of this embodiment, the effect of suppressing the relative positional deviation between the land 16 and the metal plate 20 in the second direction (the direction of the arrow C shown in FIG. 9(c)) can be obtained.

[0031] In this embodiment, in the surface of the protruding portion 22 facing the end portion 15, a fillet 33 is formed along the through hole 24 in a portion facing the non-forming region 18, as shown in Fig. 9(e) for example. The fillet 33 has an inverted shape compared to the fillet 31.

[0032] [Fourth embodiment] Next, a fourth embodiment will be described with reference to FIG. 11 to FIG. 11 shows an enlarged view of one metal plate 20 and an area corresponding to an end 15 of one extension portion 12 corresponding to the metal plate 20. Fig. 12(a) shows an enlarged view of the area corresponding to one end 15. Fig. 12(b) shows an enlarged view of the area corresponding to one protrusion 22. Wiring 17 is omitted from Fig. 12(a) and Fig. 12(c). The voltage monitoring module 100 of this embodiment differs from the voltage monitoring module 100 of the third embodiment described above in the points described below, but in other respects is configured in the same way as the voltage monitoring module 100 of the third embodiment described above.

[0033] In the present embodiment, as shown in FIG. 11 and FIG. 12(c), when viewed in the thickness direction of the metal plate 20, a portion of the land 16 protrudes from the outline of the metal plate 20. As a result, a fillet 34 (Figures 12(c) and 12(d)) can be formed also in the portion of the land 16 that protrudes from the metal plate 20 (the protruding piece 16b described later), making it possible to inspect the fillet (fillet 31 or fillet 34) more easily and reliably.

[0034] The shape of the land 16 is not particularly limited, but as an example, the land 16 is formed in a shape having a rectangular main portion 16a and a pair of left and right protruding pieces 16b protruding from the main portion 16a. The non-forming region 18 is formed in the main portion 16a. In this embodiment, the shape of the non-forming region 18 is the same as in the third embodiment. In this embodiment, too, the effect of suppressing the relative positional deviation between the land 16 and the metal plate 20 in the second direction (the up-down direction in FIG. 12(c)) can be obtained. 12(c), the left protruding piece 16b protrudes leftward from the outline (of the protruding portion 22) of the metal plate 20, and the right protruding piece 16b protrudes rightward from the outline (of the protruding portion 22) of the metal plate 20. A fillet 34 is formed on each protruding piece 16b. As shown in FIG. 12(d), the fillet 34 is formed up to the edge of the land 16, for example.

[0035] Fifth embodiment Next, a fifth embodiment will be described with reference to FIG. The voltage monitoring module 100 of this embodiment differs from the voltage monitoring module 100 of the first embodiment described above in the points described below, but in other respects is configured in the same way as the voltage monitoring module 100 of the first embodiment described above.

[0036] In this embodiment, the flexible printed circuit board 10 does not have the extending portion 12, and wiring 17 and lands 16 are disposed in a portion corresponding to the main body portion 11 in the first embodiment. In this embodiment, the metal plate 20 is a metal tab that is connected to the bus bar 50. The bus bar 50 is welded to the metal plate 20. Although not shown in FIG. 13, the voltage monitoring module 100 includes a plurality of metal plates 20 and a plurality of bus bars 50, and the plurality of bus bars 50 connect the plurality of battery cells 70 in series.

[0037] Although the embodiments have been described above with reference to the drawings, these are merely examples of the present invention, and various configurations other than those described above can also be adopted.

[0038] Moreover, the above-described embodiments can be appropriately combined without departing from the spirit of the present invention. For example, when the shapes of the through holes 24 and the non-forming regions 18 are the shapes of the first, third, or fourth embodiments, a plurality of through holes 24 may be formed in one metal plate 20, and a plurality of non-forming regions 18 may exist in one land 16.

[0039] The present embodiment encompasses the following technical ideas. (1) A flexible printed circuit board having a plurality of wirings and a plurality of lands each having one end connected to the wirings; a plurality of metal plates disposed on the lands and soldered to the lands; Equipped with a through hole is formed in a part of the metal plate corresponding to the land, A voltage monitoring module in which a portion of the land corresponding to a part of the through hole is a non-formed area where no conductor is formed. (2) A voltage monitoring module according to (1), wherein the land is located inside the outline of the metal plate when viewed in the thickness direction of the metal plate. (3) A voltage monitoring module according to (1), wherein a portion of the land protrudes beyond the outline of the metal plate when viewed in the thickness direction of the metal plate. (4) The voltage monitoring module according to any one of (1) to (3), wherein the non-forming area is contained inside the through hole when viewed in the thickness direction of the metal plate. (5) A voltage monitoring module according to any one of (1) to (3), wherein a portion of the non-forming region protrudes from the through hole when viewed in the thickness direction of the metal plate. (6) The voltage monitoring module according to any one of (1) to (5), wherein at least one of the through hole and the non-forming area is non-circular. (7) A voltage monitoring module according to any one of (1) to (6), wherein a plurality of the through holes are formed in one of the metal plates, and a plurality of the non-formed areas exist in one of the lands. (8) The voltage monitoring module according to any one of (1) to (7), wherein the metal plate is a bus bar that connects a plurality of battery cells in series. (9) A voltage monitoring module according to any one of (1) to (7), wherein the metal plate is a metal tab connected to a bus bar. [Explanation of symbols]

[0040] 10 Flexible Printed Circuit Board 11 Main body 12 Extension 15 End 16 Rand 16a Main part 16b Projecting piece 17 Wiring 18 Non-formation area 20 metal plate 21 Main body 22 Protrusion 23 fixing hole 24 Through holes 30 Solder 31, 32, 33, 34 Fillet 50 Busbar 70 Battery Cells 100 Voltage Monitoring Module

Claims

1. A flexible printed circuit board having a plurality of wirings and a plurality of lands each having one end connected to the wirings; a plurality of metal plates disposed on the lands and soldered to the lands; Equipped with a through hole is formed in a part of the metal plate corresponding to the land, a portion of the land corresponding to a portion of the through hole is a non-forming region where no conductor is formed; A voltage monitoring module in which, when viewed in the thickness direction of the metal plate, the area of ​​the through hole is larger than the area of ​​the non-forming area, and the entire outline of the non-forming area is positioned at a position spaced inside the inner edge of the through hole.

2. 2. The voltage monitoring module according to claim 1, wherein the land is located inside an outline of the metal plate when viewed in the thickness direction of the metal plate.

3. 2. The voltage monitoring module according to claim 1, wherein a portion of the land protrudes from an outline of the metal plate when viewed in the thickness direction of the metal plate.

4. The voltage monitoring module according to claim 1 , wherein at least one of the through hole and the non-forming area is non-circular.

5. The voltage monitoring module according to claim 1 , wherein a plurality of the through holes are formed in one of the metal plates, and a plurality of the non-formed areas are present in one of the lands.

6. The voltage monitoring module according to claim 1 , wherein the metal plate is a bus bar that connects a plurality of battery cells in series.

7. The voltage monitoring module according to claim 1 , wherein the metal plate is a metal tab that is connected to a bus bar.

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