Battery module

Abstract

To improve detection accuracy of light produced when a battery fails in a battery module including an optical sensor.SOLUTION: A battery module 1 includes: a lead plate 20 electrically connecting a plurality of batteries 10; and an optical sensor 40. The lead plate 20 includes: a plate-shaped body 21 where a plurality of through holes 21a each overlapping with a terminal 11 of each battery 10 in plan view are arranged; and a plurality of tabs 22. The tabs 22 each include: a plate-shaped first tab 23 that is inside a peripheral edge of the through hole 21a of each body 21 in the plan view and that electrically connects the terminal 11; and a second tab 24 for electrically connecting the first tab 23 and the body 21. The second tab 24 has a shape protruding from the body 21 to a side opposite the battery 10 side. The optical sensor 40 is located on a side opposite the battery 10 with the body 21 sandwiched therebetween.SELECTED DRAWING: Figure 1

Description

[Technical Field]

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

[0002] Patent Document 1 discloses, as an example of a battery module, a battery module including a plurality of cells, a plurality of fusible links that melt when a short occurs between the anode and cathode of a cell, and a photodetector that detects the light emitted when the fusible links melt. When the photodetector detects the light, a failure of the cell corresponding to the melted fusible link is detected. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Publication No. 2023-29826 Summary of the Invention [Problem to be solved by the invention]

[0004] However, depending on the relative positions of the multiple fusible links and the photodetector (photosensor), it may be difficult for the photodetector to detect the light emitted when a cell (battery) fails.

[0005] The present disclosure has been made in view of the above, and aims to improve the detection accuracy of light generated when a battery fails in a battery module equipped with a photosensor. [Means for solving the problem]

[0006] The battery module of the present disclosure comprises a plurality of batteries each having a terminal, a lead plate positioned opposite the terminals of the batteries and electrically connecting to each of the plurality of batteries, and an optical sensor, wherein the lead plate integrally comprises a plate-shaped main body portion having a plurality of through holes each overlapping with the terminals of the batteries in a planar view, and a plurality of tab portions, each of the plurality of tab portions being located inside the periphery of the through hole in a planar view of the main body portion and comprising: a plate-shaped first tab portion electrically connecting to the terminal of the battery; and a second tab portion electrically connecting the first tab portion and the main body portion, wherein a first end of the second tab portion is electrically connected to a portion of the periphery of the first tab portion and a second end is electrically connected to a portion of the periphery of the through hole and is shaped to protrude from the main body portion on the side opposite the batteries, and the optical sensor is located on the opposite side of the main body portion from the batteries in a side view of the main body portion. [Effects of the Invention]

[0007] According to the present disclosure, it is possible to improve the accuracy of detecting light generated when a battery fails in a battery module equipped with a light sensor. [Brief explanation of the drawings]

[0008] [Figure 1] FIG. 1 is a perspective view of a battery module according to a first embodiment of the present disclosure. [Figure 2] FIG. 2 is a side view of the battery module shown in FIG. 1 as viewed along the X direction. [Figure 3] FIG. 3 is a side view of the battery module shown in FIG. 1 as viewed along the Y direction. [Figure 4] FIG. 4 is a perspective view of the tab portion shown in FIG. [Figure 5] FIG. 5 is a diagram showing a cross-sectional shape of the tab portion shown in FIG. [Figure 6] FIG. 6 is a side view of the lead plate shown in FIG. 3 when viewed along the row direction. [Figure 7] FIG. 7 is a side view of a battery module according to a first modified example of the first embodiment of the present disclosure, as viewed along the Y direction. [Figure 8] FIG. 8 is a side view of the lead plate shown in FIG. 7 when viewed along the row direction. [Figure 9A] FIG. 9A is a side view of a lead plate provided in a battery module according to a second variant of the first embodiment of the present disclosure, viewed along the column direction, in which the second tab portions included in the first row of the second tab portions are indicated by solid lines, and the other second tab portions are indicated by dashed lines. [Figure 9B] FIG. 9B is a side view of the lead plate shown in FIG. 9A, in which the second tab portions included in the second row of the second tab portions are shown by solid lines, and the other second tab portions are shown by dashed lines. [Figure 9C] Figure 9C is a side view of the lead plate shown in Figure 9A, in which the second tab portions included in the third row of the second tab portions are shown with solid lines, and the other second tab portions are shown with dashed lines. [Figure 9D] FIG. 9D is a side view of the lead plate shown in FIG. 9A, in which the second tab portions included in the fourth row of the second tab portions are shown by solid lines, and the other second tab portions are shown by dashed lines. [Figure 10] FIG. 10 is a side view of the battery module according to the second embodiment of the present disclosure as viewed along the Y direction. [Figure 11] 11 is a perspective view of a tab portion of the lead plate shown in FIG. [Figure 12] FIG. 12 is a side view of the lead plate shown in FIG. 10 as viewed along the row direction. [Figure 13] FIG. 13 is a side view of the battery module according to the second embodiment of the present disclosure as viewed along the Y direction. [Figure 14] FIG. 14 is a side view of the lead plate shown in FIG. 13 when viewed along the row direction. [Figure 15] FIG. 15 is a side view of the battery module according to the third embodiment of the present disclosure as viewed along the Y direction. [Figure 16] FIG. 16 is a side view of the lead plate shown in FIG. 15 as viewed along the row direction. [Figure 17A]FIG. 17A is a side view of a lead plate provided in a battery module according to a modified example of the third embodiment of the present disclosure, viewed along the column direction, in which the second tab portions included in the tab portions in the first row are indicated by solid lines, and the other second tab portions are indicated by dashed lines. [Figure 17B] FIG. 17B is a side view of the lead plate shown in FIG. 17A, in which the second tab portions included in the second row of tab portions are indicated by solid lines, and the other second tab portions are indicated by dashed lines. [Figure 17C] FIG. 17C is a side view of the lead plate shown in FIG. 17A, in which the second tab portions included in the third row of tab portions are indicated by solid lines, and the other second tab portions are indicated by dashed lines. [Figure 17D] FIG. 17D is a side view of the lead plate shown in FIG. 17A, in which the second tab portions included in the fourth row of tab portions are indicated by solid lines, and the other second tab portions are indicated by dashed lines. [Figure 18] FIG. 18 is a side view of the battery module according to the fourth embodiment of the present disclosure as viewed along the Y direction. [Figure 19] FIG. 19 is a side view of the battery module shown in FIG. 18 when viewed along the X direction. [Figure 20A] 20A is a side view of the lead plate shown in FIG. 18 when viewed from the optical sensor in the column direction, showing a plurality of second tab portions included in a plurality of tab portions in the third and fourth rows. [Figure 20B] FIG. 20B is a side view of the lead plate shown in FIG. 19 when viewed from the optical sensor in the column direction, showing a plurality of second tab portions included in a plurality of tab portions in the first and second rows. [Figure 21] FIG. 21 is a side view of the battery module according to the fourth embodiment of the present disclosure as viewed along the Y direction. [Figure 22A] 22A is a side view of the lead plate shown in FIG. 21 when viewed from the optical sensor in the column direction, showing a plurality of second tab portions included in a plurality of tab portions in the third and fourth rows. [Figure 22B]FIG. 22B is a side view of the lead plate shown in FIG. 21 when viewed from the optical sensor in the column direction, showing a plurality of second tab portions included in a plurality of tab portions in the first and second rows. [Figure 23] FIG. 23 is a side view of a battery module according to a second modified example of the fourth embodiment of the present disclosure, as viewed along the Y direction. [Figure 24A] 24A is a side view of the lead plate shown in FIG. 23 when viewed from the optical sensor along the column direction, and shows a plurality of second tab portion sets included in a plurality of tab portions in the third and fourth rows. [Figure 24B] FIG. 24B is a side view of the lead plate shown in FIG. 23 when viewed from the optical sensor in the column direction, showing a plurality of second tab portion sets included in a plurality of tab portions in the first and second rows. [Figure 25] FIG. 25 is a side view of the battery module according to the fifth embodiment of the present disclosure as viewed along the Y direction. [Figure 26] FIG. 26 is a partially enlarged view of the battery module shown in FIG. [Figure 27] FIG. 27 is a side view of the lead plate shown in FIG. 25 as viewed along the row direction. [Figure 28] FIG. 28 is a side view of the battery module according to the fifth embodiment of the present disclosure as viewed along the Y direction. [Figure 29] FIG. 29 is a side view of the battery module according to the sixth embodiment of the present disclosure as viewed along the Y direction. [Figure 30] FIG. 30 is a side view of the battery module according to the fifth embodiment of the present disclosure as viewed along the Y direction. [Figure 31A] FIG. 31A is a perspective view of a battery module according to a seventh embodiment of the present disclosure as viewed from the +Y side. [Figure 31B] FIG. 31B is a perspective view of the battery module shown in FIG. 31A as viewed from the -Y side. [Figure 32] FIG. 32 is a perspective view of a tab portion of a battery module according to another modified example of each embodiment of the present disclosure. DETAILED DESCRIPTION OF THE INVENTION

[0009] Hereinafter, embodiments will be described in detail with reference to the drawings. Note that the present disclosure is not limited to these embodiments. Each embodiment is an example, and it goes without saying that partial substitution or combination of the configurations shown in different embodiments is possible.

[0010] The X direction shown in the drawings corresponds to the width direction of the battery module 1, the Y direction corresponds to the depth direction of the battery module 1, and the Z direction corresponds to the height direction of the battery module 1. The X direction, Y direction, and Z direction are perpendicular to each other. In the X direction, the side indicated by the arrow is the +X side, and the side opposite the +X side is the -X side. In the Y direction, the side indicated by the arrow is the +Y side, and the side opposite the +Y side is the -Y side. In the Z direction, the side indicated by the arrow is the +Z side, and the side opposite the +Z side is the -Z side. Note that the X, Y, and Z directions are merely examples, and the present disclosure is not limited to these directions.

[0011] First Embodiment Fig. 1 is a perspective view of a battery module 1 according to a first embodiment of the present disclosure. Fig. 2 is a side view of the battery module 1 shown in Fig. 1 as viewed along the X direction. The battery module 1 can be used as a power source for external devices (not shown) such as electronic devices, electric vehicles, and power tools.

[0012] The battery module 1 includes a plurality of batteries 10, lead plates 20, a control board 30, and an optical sensor 40.

[0013] The battery 10 is a secondary battery such as a lithium ion battery. The battery 10 has a cylindrical shape. The battery 10 has a positive terminal 11a (corresponding to a "terminal") and a negative terminal 11b (corresponding to a "terminal") on its end surfaces. Hereinafter, when the positive terminal 11a and the negative terminal 11b are not distinguished from each other, they will be referred to as "terminals 11." Note that the battery 10 included in the battery module 1 may be a battery other than a secondary battery.

[0014] The plurality of batteries 10 are arranged in parallel. The central axes CL of the plurality of batteries 10 are parallel to one another. In this first embodiment, the central axes CL of the batteries 10 are aligned along the Y direction. The plurality of batteries 10 are arranged such that the positive electrode terminal 11a and the negative electrode terminal 11b are oriented in predetermined directions. In this first embodiment, the plurality of batteries 10 are connected in parallel.

[0015] In this first embodiment, the plurality of batteries 10 are arranged in rows and columns along both the X and Z directions. The number of batteries 10 is 20. The number of batteries 10 arranged along the X direction is 5. The number of batteries 10 arranged along the Z direction is 4. It goes without saying that the number and arrangement of the batteries 10 are not limited to the above.

[0016] The lead plates 20 are positioned opposite the terminals 11 of the batteries 10. The battery module 1 includes two lead plates 20. The two lead plates 20 are positioned on opposite sides of the multiple batteries 10. The lead plates 20 are conductive. The lead plates 20 electrically connect the batteries 10 to each other. The lead plates 20 also electrically connect the multiple batteries 10 to the control board 30. Details of the lead plates 20 will be described later.

[0017] The control board 30 controls the charging and discharging of the battery 10. The control board 30 is electrically connected to an external device and supplies (discharges) power from the battery 10 to the external device. The control board 30 is also electrically connected to a power source (e.g., a commercial power source) and supplies (charges) power from the power source to the battery 10.

[0018] The battery module 1 includes two optical sensors 40. The two optical sensors 40 are configured in the same way. The optical sensor 40 includes, for example, a photodiode in the light receiving section 41. The optical sensor 40 does not have directionality. However, the optical sensor 40 may be a directional sensor. When a directional sensor is used, the sensor may be positioned according to its directional range (detectable angle, distance, etc.) so that it can detect the entire surface of the XZ plane (see Figure 2, etc.) of the lead plate 20 (specifically, the entire second plate surface S2, which will be described later). The optical sensor 40 is positioned on the control board 30. The positioning of the optical sensor 40 will be described in detail later.

[0019] Next, a detailed description will be given of the lead plates 20. The two lead plates 20 have the same configuration.

[0020] 3 is a side view of the battery module 1 shown in FIG. 1 as viewed along the Y direction. The lead plate 20 shown in FIG. 3 includes a plan view of the main body 21, which will be described later. In other words, the side view of the battery module 1 shown in FIG. 3 shows the battery module 1 when the main body 21 is viewed in plan. The lead plate 20 has a substantially constant thickness. The lead plate 20 integrally includes the main body 21 and multiple tab portions 22.

[0021] The main body 21 is plate-shaped and has a plurality of through holes 21a that overlap the terminals 11 of the batteries 10 in a planar view. One through hole 21a overlaps one terminal 11 of one battery 10 in a planar view. The arrangement and number of the through holes 21a are the same as the arrangement and number of the batteries 10. That is, the through holes 21a in the main body 21 are arranged in a matrix along both the X and Z directions. Furthermore, in this first embodiment, the number of through holes 21a is 20. The number of through holes 21a arranged along the X direction is five. The number of through holes 21a arranged along the Z direction is four. Furthermore, as shown in FIGS. 1 and 2 , the main body 21 has a strip-shaped connection portion 21b that extends from a side surface of the main body 21 and electrically connects to the control board 30.

[0022] As shown in FIG. 3 , the multiple tab portions 22 are arranged in a matrix along both the row and column directions in a plan view of the main body portion 21. The arrangement and number of the multiple tab portions 22 are the same as the arrangement and number of the multiple batteries 10. That is, the multiple tab portions 22 in the main body portion 21 are arranged in a matrix along both the X direction and the Z direction. Furthermore, in this first embodiment, the number of tab portions 22 is 20. The number of tab portions 22 arranged along the X direction is 5. The number of tab portions 22 arranged along the Z direction is 4.

[0023] Hereinafter, the X direction may be referred to as the row direction, and the Z direction may be referred to as the column direction. Furthermore, "(i, j)" attached to the symbols for tab portion 22 shown in the drawing and second tab portion 24 and protrusion height H of second tab portion 24 described below indicates that the tab portion 22 and the tab portion 22 having the second tab portion 24 are located in the ith and jth columns of the multiple tab portions 22 arranged in a matrix.

[0024] The "i" in "(i,j)" is a natural number indicating the row number. The row number closest to the -Z side is "1", and the row number increases from the -Z side to the +Z side. Specifically, there are four rows of tab portions 22 shown in FIG. 3, and the row numbers of these four rows are 1, 2, 3, and 4, in order, from the -Z side to the +Z side.

[0025] Additionally, "j" in "(i,j)" is a natural number indicating the column number. The column number closest to the -X side is "1," and the column number increases from the -X side to the +X side. Specifically, there are five columns of tab portions 22 shown in FIG. 3, and the column numbers of the five columns are 1, 2, 3, 4, and 5 from the -X side to the +X side.

[0026] Fig. 4 is a perspective view of the tab portion 22 shown in Fig. 3. Fig. 5 is a view showing the cross-sectional shape of the tab portion 22 shown in Fig. 3. As shown in Figs. 3, 4, and 5, each of the multiple tab portions 22 integrally includes a first tab portion 23 and a second tab portion 24.

[0027] The first tab portion 23 is located inside the periphery of the through hole 21a in a plan view of the main body portion 21. One first tab portion 23 is disposed in one through hole 21a. The first tab portion 23 is electrically connected to the terminal 11 of the battery 10. The first plate surface S1 of the first tab portion 23 facing the battery 10 contacts and electrically connects with the terminal 11 of the battery 10.

[0028] The second tab portion 24 is strip-shaped and electrically connects the first tab portion 23 and the main body portion 21. Specifically, a first end of the second tab portion 24 is electrically connected to a portion of the periphery of the first tab portion 23, and a second end of the second tab portion 24 is electrically connected to a portion of the periphery of the through hole 21a. In the first embodiment, the first end of the second tab portion 24 is electrically connected to a portion on the -Z side of the first tab portion 23, and the second end of the second tab portion 24 is electrically connected to a portion on the -Z side of the through hole 21a. The cross-sectional area of ​​the second tab portion 24 perpendicular to the direction in which the second tab portion 24 extends is smaller than the cross-sectional area of ​​the first tab portion 23 along the thickness direction.

[0029] 5 has a U-shaped cross section that protrudes from the main body 21 to the opposite side (-Y side in FIG. 5) from the battery 10 side (+Y side in FIG. 5) and is open to the battery 10. Hereinafter, the length in the Y direction from the second plate surface S2 of the main body 21, which is on the opposite side from the first plate surface S1 of the first tab portion 23, to the protruding end T of the second tab portion 24 is defined as the protruding height H of the second tab portion 24.

[0030] Fig. 6 is a side view of the lead plate 20 shown in Fig. 3 as viewed along the column direction. As shown in Figs. 3 and 6, the multiple second tab portions 24 are arranged in a matrix along the row and column directions. That is, the multiple second tab portions 24 included in multiple tab portions 22 with the same row number among the multiple tab portions 22 are arranged along the row direction. Also, the multiple second tab portions 24 included in multiple tab portions 22 with the same column number among the multiple tab portions 22 are arranged along the column direction.

[0031] 6, the protruding height H of the second tab portions 24 increases from the −Z side toward the +Z side in the Z direction. That is, the protruding height H of the second tab portions 24 included in the tab portions 22 having the same column number increases as the column number increases.

[0032] Furthermore, the second tab portions 24 included in the tab portions 22 of the same row number among the multiple second tab portions 24 have the same protrusion height H. In other words, the protrusion heights H of the second tab portions 24 included in the tab portions 22 of the same row among the multiple tab portions 22 are equal to each other. "H1," "H2," "H3," and "H4" shown in FIG. 6 respectively refer to the protrusion height H of the five second tab portions 24 in the first row, the protrusion height H of the five second tab portions 24 in the second row, the protrusion height H of the five second tab portions 24 in the third row, and the protrusion height H of the five second tab portions 24 in the fourth row.

[0033] 2, the optical sensor 40 is disposed on the opposite side of the lead plate 20 from the plurality of batteries 10 in a side view of the main body 21. The distance D in the Z direction between the light receiving portion 41 of the optical sensor 40 and the second plate surface S2 of the main body 21 is equal to or greater than the protruding height H of the second tab portion 24 closest to the optical sensor 40.

[0034] 3, the optical sensor 40 is located outside the second tab portions 24 in the column direction when viewed from above the main body portion 21. In the first embodiment, the optical sensor 40 is located on the -Z side of the second tab portions 24. Furthermore, the optical sensor 40 is located at the center of the main body portion 21 in the row direction when viewed from above the main body portion 21.

[0035] With the lead plate 20 configured and the optical sensor 40 positioned as described above, the multiple second tab portions 24 and the optical sensor 40 have the following positional relationship. That is, the protruding height H of the multiple second tab portions 24 increases as they move away from the optical sensor 40 in the column direction. Furthermore, when one second tab portion 24 of the multiple second tab portions 24 is viewed from the optical sensor 40, the protruding end T of that one second tab portion 24 does not overlap with any of the other second tab portions 24 of the multiple second tab portions 24 other than that one second tab portion 24.

[0036] Furthermore, the multiple second tab portions 24 include two second tab portions 24 having different distances from the optical sensor 40, and of the two second tab portions 24, the protruding height H of the second tab portion 24 having a longer distance from the optical sensor 40 is higher than the protruding height H of the second tab portion 24 having a shorter distance from the optical sensor 40.

[0037] Next, the operation of the battery module 1 when an abnormality occurs in the battery 10 causing an overcurrent will be described.

[0038] If an abnormality occurs in the battery 10, an overcurrent will flow through the lead plate 20. As described above, the cross-sectional area of ​​the second tab portion 24 perpendicular to the extension direction of the second tab portion 24 is smaller than the cross-sectional area along the thickness direction of the first tab portion 23. Therefore, the second tab portion 24 functions as a fuse that melts down due to an overcurrent. The second tab portion 24 corresponding to the abnormal battery 10 will melt down due to the overcurrent. The second tab portion 24 will emit light when it melts down.

[0039] The multiple second tab portions 24 and the optical sensor 40 have the above-described positional relationship. Therefore, the light generated when the second tab portion 24 melts reaches the optical sensor 40 directly. Therefore, the optical sensor 40 can accurately detect the light generated when the second tab portion 24 melts. When the optical sensor 40 detects the light, the control board 30 stops charging and discharging the battery module 1, for example.

[0040] In this way, the accuracy of detecting light generated when a battery 10 fails in a battery module 1 equipped with an optical sensor 40 can be improved.

[0041] The optical sensor 40 may be disposed at a position other than the center of the main body 21 in the row direction. Furthermore, the optical sensor 40 may be positioned further outward in the row direction than the plurality of tab portions 22, as long as the protruding end T of one of the plurality of second tab portions 24 does not overlap with any of the other second tab portions 24 when viewed from the optical sensor 40. Furthermore, the Z-direction distance D between the light receiving portion 41 of the optical sensor 40 and the second plate surface S2 of the main body 21 may be smaller than the protruding height H of the second tab portion 24 closest to the optical sensor 40.

[0042] <First Modification of First Embodiment> Next, the battery module 1 according to the first modification of the first embodiment will be described, focusing mainly on the differences from the battery module 1 according to the first embodiment described above.

[0043] Fig. 7 is a side view of a battery module 1 according to a first modified example of the first embodiment of the present disclosure, viewed along the Y direction. Fig. 8 is a side view of the lead plate 120 shown in Fig. 7, viewed along the column direction. The lead plate 120 includes a main body portion 121 and multiple tab portions 122. The tab portion 122 has a first tab portion 123 and a second tab portion 124.

[0044] In this first modified example, the second tab portions 124 are located at different positions in the row direction. Specifically, the second tab portions 124 included in the tab portions 122 in the same column among the tab portions 122 are located at different positions in the row direction. In other words, the second tab portions 124 included in the tab portions 122 with the same column number do not overlap with each other when viewed along the column direction.

[0045] In this first modified example, in tab portions 122 in the first, second, and third columns, the second tab portions 124 included in the tab portions 122 with the same column number are shifted from the -X side toward the +X side along the X direction as they move from the -Z side toward the +Z side along the Z direction. Also, in tab portions 122 in the fourth and fifth columns, the second tab portions 124 included in the tab portions 122 with the same column number are shifted from the +X side toward the -X side along the X direction as they move from the -Z side toward the +Z side along the Z direction. It goes without saying that the positions of the second tab portions 124 included in the tab portions 122 with the same column number in this first modified example are not limited to the positions described above.

[0046] In this first modified example, as in the first embodiment described above, when one of the multiple second tab portions 124 is viewed from the optical sensor 40, the protruding end T of that one second tab portion 124 does not overlap with any of the other second tab portions 124 among the multiple second tab portions 124. Therefore, light generated when the second tab portion 124 melts reaches the optical sensor 40 directly. This improves the accuracy of detecting light generated when a battery 10 fails in a battery module 1 equipped with the optical sensor 40.

[0047] <Second Modification of First Embodiment> Next, the battery module 1 according to the second modification of the first embodiment will be described, focusing mainly on the differences from the battery module 1 according to the first modification of the first embodiment described above.

[0048] In this second modified example, the arrangement of the second tab portions 224 of the lead plate 220 is the same as the arrangement of the second tab portions 124 in the first modified example of the first embodiment shown in Fig. 7. Furthermore, the protruding height H of the second tab portions 224 increases with increasing distance from the optical sensor 40 in the column direction.

[0049] 9A is a side view of a lead plate 220 included in a battery module 1 according to a second modified example of the first embodiment of the present disclosure, viewed along the column direction, in which solid lines indicate second tab portions 224 included in a first row of tab portions 222 among the second tab portions 224, and dashed lines indicate other second tab portions 224. FIG. 9B is a side view of the lead plate 220 shown in FIG. 9A, in which solid lines indicate second tab portions 224 included in a second row of tab portions 222 among the second tab portions 224, and dashed lines indicate other second tab portions 224.

[0050] Fig. 9C is a side view of the lead plate 220 shown in Fig. 9A, in which the second tab portions 224 included in the third row of tab portions 222 among the second tab portions 224 are indicated by solid lines, and the other second tab portions 224 are indicated by dashed lines. Fig. 9D is a side view of the lead plate 220 shown in Fig. 9A, in which the second tab portions 224 included in the fourth row of tab portions 222 among the second tab portions 224 are indicated by solid lines, and the other second tab portions 224 are indicated by dashed lines.

[0051] In the second modified example, the protruding height H of the second tab portions 224 increases as they move away from the optical sensor 40 in the row direction.

[0052] As described above, the optical sensor 40 is located at the center of the main body portion 221 in the row direction. Therefore, as shown in FIGS. 9A, 9B, 9C, and 9D, among the second tab portions 224 included in the tab portions 222 of the same row number, the protruding height H of the second tab portion 224 included in the tab portion 222 in the third column, which is closest to the center of the main body portion 221 in the row direction, is the smallest. Furthermore, among the second tab portions 224 included in the tab portions 222 of the same row number, the protruding height H of the second tab portions 224 included in the tab portions 222 in the second and fourth columns is higher than the protruding height H of the second tab portion 224 included in the tab portion 222 in the third column. Furthermore, in this second modified example, the protruding heights H of the second tab portions 224 included in the tab portions 222 in the second and fourth columns are equal to each other. The protruding heights H of the second tab portions 224 included in the tab portions 222 in the second and fourth columns may be different from each other.

[0053] Furthermore, among the multiple second tab portions 224 included in the multiple tab portions 222 of the same row number, the protruding height H of the second tab portions 224 included in the tab portions 222 in the first and fifth columns is higher than the protruding height H of the second tab portions 224 included in the tab portions 222 in the second and fourth columns. In this second modified example, the protruding heights H of the second tab portions 224 included in the tab portions 222 in the first and fifth columns are equal to each other. Note that the protruding heights H of the second tab portions 224 included in the tab portions 222 in the first and fifth columns may be different from each other.

[0054] In this second modification, as in the first modification of the first embodiment, when one of the multiple second tab portions 224 is viewed from the optical sensor 40, the protruding end T of the one second tab portion 224 does not overlap with the other second tab portions 224 of the multiple second tab portions 224. In other words, the protruding ends T of the multiple second tab portions 224 are offset in the protruding direction (Y direction) and the X direction of the second tab portion 224. Therefore, light generated when the second tab portion 224 melts reaches the optical sensor 40 directly. This improves the detection accuracy of light generated when a battery 10 fails in a battery module 1 equipped with the optical sensor 40.

[0055] Second Embodiment Next, the battery module 1 according to the second embodiment will be described, focusing mainly on the differences from the battery module 1 according to the first embodiment.

[0056] Fig. 10 is a side view of a battery module 1 according to a second embodiment of the present disclosure as viewed along the Y direction. Fig. 11 is a perspective view of a tab portion 322 of a lead plate 320 shown in Fig. 10. The lead plate 320 includes a main body portion 321 and a plurality of tab portions 322.

[0057] In the second embodiment, each of the plurality of tab portions 322 includes a plurality of second tab portions 324. In the second embodiment, the number of second tab portions 324 included in the tab portion 322 is two, but it goes without saying that the number is not limited to two.

[0058] Each of the multiple first tab portions 323 is electrically connected to the main body portion 321 by two second tab portions 324. First ends of the two second tab portions 324 are electrically connected to portions of the first tab portion 323 on the -Z side. Specifically, the first end of one of the two second tab portions 324 is electrically connected to a portion of the -Z side portion of the first tab portion 323 on the +X side. Furthermore, the first end of the other of the two second tab portions 324 is electrically connected to a portion of the -Z side portion of the first tab portion 323 on the -X side. Second ends of the two second tab portions 324 are electrically connected to portions of the -Z side of the through hole 321a. Specifically, the second end of one of the two second tab portions 324 is electrically connected to a portion of the -Z side portion of the through hole 321a on the +X side. Furthermore, a first end of the other of the two second tab portions 324 is electrically connected to a location on the -X side of the -Z side portion of the through-hole 321a. The two second tab portions 324 have the same protruding height H. Hereinafter, the two second tab portions 324 are referred to as a "second tab portion set C." Each of the multiple first tab portions 323 is electrically connected to the main body portion 321 by one second tab portion set C.

[0059] Fig. 12 is a side view of the lead plate 320 shown in Fig. 10 when viewed along the column direction. As shown in Figs. 10 and 12, in the second embodiment, the multiple second tab portion sets C are arranged in a matrix. In the multiple second tab portion sets C included in the multiple tab portions 322 with the same column number among the multiple tab portions 322, the multiple second tab portions 324 are arranged in two rows along the column direction.

[0060] Furthermore, similar to the battery module 1 of the first embodiment described above, the protruding height H of the second tab portions 324 increases in the column direction as they are farther away from the optical sensor 40. Furthermore, the protruding heights H of the second tab portions 324 included in the tab portions 322 in the same row among the tab portions 322 are equal to each other.

[0061] In the second embodiment, as in the first embodiment, when one of the multiple second tab portions 324 is viewed from the optical sensor 40, the protruding end T of that one second tab portion 324 does not overlap with any of the other second tab portions 324. Therefore, light generated when the second tab portion 324 melts reaches the optical sensor 40 directly. This improves the accuracy of detecting light generated when a battery 10 fails in a battery module 1 equipped with the optical sensor 40.

[0062] In the second embodiment, a first end of one of the two second tab portions 324 is electrically connected to a location on the +X side of the -Z side portion of the first tab portion 323. A first end of the other of the two second tab portions 324 is electrically connected to a location on the -X side of the -Z side portion of the first tab portion 323. A second end of one of the two second tab portions 324 is electrically connected to a location on the +X side of the -Z side portion of the through hole 321a. A first end of the other of the two second tab portions 324 is electrically connected to a location on the -X side of the -Z side portion of the through hole 321a. By providing the two second tab portions 324 at the above positions (in other words, positions where the two second tab portions 324 are spaced apart when viewed from a predetermined direction), the durability of the tab portion 322 when a force acts in a twisting direction of the tab portion 322 is improved compared to the first embodiment (where the tab portion 22 has one second tab portion 24). This makes it possible to prevent damage to the tab portion 322 even if a force acts in a twisting direction of the tab portion 322 due to a blow or vibration to the battery module, for example.

[0063] <Modification of the second embodiment> Next, a battery module 1 according to a modification of the second embodiment will be described, focusing mainly on the differences from the battery module 1 according to the second embodiment described above.

[0064] Fig. 13 is a side view of a battery module 1 according to a second embodiment of the present disclosure as viewed along the Y direction. Fig. 14 is a side view of a lead plate 420 shown in Fig. 13 as viewed along the column direction. The lead plate 420 includes a main body portion 421 and multiple tab portions 422. The tab portion 422 includes one first tab portion 423 and two second tab portions 424 (second tab portion set C).

[0065] In this modification, the second tab portions 424 included in the tab portions 422 in the same column among the tab portions 422 are located at different positions in the row direction. In other words, the second tab portions 424 included in the tab portions 422 with the same column number do not overlap with each other when viewed in the column direction.

[0066] In this modification, in the tab portions 422 in the first and second rows, the second tab portion sets C included in the tab portions 422 with the same row number are shifted from the -X side toward the +X side along the X direction as they move from the -Z side toward the +Z side along the Z direction. Also, in the tab portions 422 in the third, fourth, and fifth rows, the second tab portion sets C included in the tab portions 422 with the same row number are shifted from the +X side toward the -X side along the X direction as they move from the -Z side toward the +Z side along the Z direction.

[0067] In this modification, as in the first embodiment, when one of the multiple second tab portions 424 is viewed from the optical sensor 40, the protruding end T of the one second tab portion 424 does not overlap with the other second tab portions 424 of the multiple second tab portions 424. In other words, the protruding ends T of the multiple second tab portions 424 are offset in the protruding direction (Y direction) and the X direction of the second tab portion 424. Therefore, light generated when the second tab portion 424 melts reaches the optical sensor 40 directly. This improves the detection accuracy of light generated when a battery 10 fails in a battery module 1 equipped with the optical sensor 40.

[0068] Third Embodiment Next, the battery module 1 according to the third embodiment will be described, focusing mainly on the differences from the battery module 1 according to the first embodiment.

[0069] Fig. 15 is a side view of a battery module 1 according to a third embodiment of the present disclosure as viewed along the Y direction. Fig. 16 is a side view of a lead plate 520 shown in Fig. 15 as viewed along the column direction. The lead plate 520 includes a main body portion 521 and multiple tab portions 522. The tab portion 522 includes a first tab portion 523 and a second tab portion 524.

[0070] In the battery module 1 of the third embodiment, compared to the battery module 1 of the first embodiment described above, each of the plurality of tab portions 522 in the first row, including the tab portion 522 closest to the optical sensor 40, has one second tab portion 524, and each of the plurality of tab portions 522 in the second, third, and fourth rows has a second tab portion set C made up of two second tab portions 524. Furthermore, in the plurality of tab portions 522 in the second, third, and fourth rows, the spacing between the two second tab portions 524 that make up the second tab portion set C becomes wider as they are farther away from the optical sensor 40 in the column direction.

[0071] As a result, the second tab portions 524 included in the tab portions 522 of the same column number are arranged in a V shape in a plan view of the main body portion 21, and do not overlap with each other when viewed along the column direction.

[0072] Similarly to the battery module 1 of the first embodiment, the protruding height H of the second tab portions 524 increases as they move away from the optical sensor 40 in the column direction. The protruding heights H of the second tab portions 524 included in the tab portions 522 in the same row among the tab portions 522 are equal to each other.

[0073] In the third embodiment, as in the first embodiment, when one of the multiple second tab portions 524 is viewed from the optical sensor 40, the protruding end T of that one second tab portion 524 does not overlap with any of the other second tab portions 524. Therefore, light generated when the second tab portion 524 melts reaches the optical sensor 40 directly. This improves the accuracy of detecting light generated when a battery 10 fails in a battery module 1 equipped with the optical sensor 40.

[0074] <Modification of the third embodiment> Next, a battery module 1 according to a modification of the third embodiment will be described, focusing mainly on the differences from the battery module 1 according to the third embodiment. In this modification, the arrangement of the second tab portions 624 is the same as the arrangement of the second tab portions 524 in the third embodiment shown in FIG. 15. The protruding height H of the second tab portions 624 increases with increasing distance from the optical sensor 40 in the column direction. The protruding height H of the two second tab portions 624 constituting one second tab portion set C is equal to each other.

[0075] Fig. 17A is a side view of a lead plate 620 included in a battery module 1 according to a modified example of the third embodiment of the present disclosure, viewed along the column direction, in which the second tab portions 624 included in the tab portions 622 in the first row are indicated by solid lines and the other second tab portions 624 are indicated by dashed lines. Fig. 17B is a side view of the lead plate 620 shown in Fig. 17A, in which the second tab portions 624 included in the tab portions 622 in the second row are indicated by solid lines and the other second tab portions 624 are indicated by dashed lines.

[0076] Fig. 17C is a side view of the lead plate 620 shown in Fig. 17A, in which the second tab portions 624 included in the third row of tab portions 622 are indicated by solid lines and the other second tab portions 624 are indicated by dashed lines. Fig. 17D is a side view of the lead plate 620 shown in Fig. 17A, in which the second tab portions 624 included in the fourth row of tab portions 622 are indicated by solid lines and the other second tab portions 624 are indicated by dashed lines.

[0077] In this modified example, the protrusion height H of the second tab portions 624 included in the tab portions 622 in the first row increases as the tab portions 622 are farther away from the optical sensor 40 in the row direction. As described above, the optical sensor 40 is located at the center of the main body portion 621 in the row direction. Therefore, as shown in FIG. 17A , among the second tab portions 624 included in the tab portions 622 in the first row, the protrusion height H of the second tab portion 624 included in the tab portion 622 in the third column, which is closest to the optical sensor 40, is the smallest.

[0078] Furthermore, among the second tab portions 624 included in the tab portions 622 in the first row, the protruding height H of the second tab portions 624 included in the tab portions 622 in the second and fourth columns is higher than the protruding height H of the second tab portions 624 included in the tab portions 622 in the third column. In this modification, the protruding heights H of the second tab portions 624 included in the tab portions 622 in the second and fourth columns are equal to each other. However, the protruding heights H of the second tab portions 624 included in the tab portions 622 in the second and fourth columns may be different from each other.

[0079] Furthermore, among the second tab portions 624 included in the tab portions 622 in the first row, the protruding height H of the second tab portions 624 included in the tab portions 622 in the first and fifth columns is higher than the protruding height H of the second tab portions 624 included in the tab portions 622 in the second and fourth columns. In this modified example, the protruding heights H of the second tab portions 624 included in the tab portions 622 in the first and fifth columns are equal to each other. Note that the protruding heights H of the second tab portions 624 included in the tab portions 622 in the first and fifth columns may be different from each other.

[0080] Also, as shown in Figures 17B, 17C, and 17D, among multiple second tab portion sets C included in multiple tab portions 622 with the same row number, the protruding height H of the two second tab portions 624 included in the second tab portion set C that is farther from the optical sensor 40 of two second tab portion sets C adjacent to each other in the row direction is higher than the protruding height H of the two second tab portions 624 included in the second tab portion set C that is closer to the optical sensor 40.

[0081] That is, among the plurality of second tab portion sets C included in the plurality of tab portions 622 in the second, third, and fourth rows, the protruding height H of the second tab portion 624 included in the tab portion 622 in the third column is the smallest.

[0082] Furthermore, in a plurality of second tab portion sets C included in a plurality of tab portions 622 of the same row numbers as the plurality of tab portions 622 in the second, third, and fourth rows, the protruding height H of the plurality of second tab portions 624 included in the tab portions 622 in the second and fourth columns is higher than the protruding height H of the plurality of second tab portions 624 included in the tab portion 622 in the third column. The protruding heights H of the plurality of second tab portions 624 included in the tab portions 622 in the second and fourth columns are equal to each other. Note that the protruding heights H of the plurality of second tab portions 624 included in the tab portions 622 in the second and fourth columns may be different from each other.

[0083] Furthermore, in a plurality of second tab portion sets C included in the plurality of tab portions 622 of the same row numbers as the plurality of tab portions 622 in the second, third, and fourth rows, the protruding height H of the plurality of second tab portions 624 included in the tab portions 622 in the first and fifth columns is higher than the protruding height H of the plurality of second tab portions 624 included in the tab portions 622 in the second and fourth columns. The protruding heights H of the plurality of second tab portions 624 included in the tab portions 622 in the first and fifth columns are equal to each other. Note that the protruding heights H of the plurality of second tab portions 624 included in the tab portions 622 in the first and fifth columns may be different from each other.

[0084] In this modification, as in the third embodiment, when one of the multiple second tab portions 624 is viewed from the optical sensor 40, the protruding end T of the one second tab portion 624 does not overlap with the other second tab portions 624 of the multiple second tab portions 624. In other words, the protruding ends T of the multiple second tab portions 624 are offset in the protruding direction (Y direction) and the X direction of the second tab portion 624. Therefore, light generated when the second tab portion 624 melts reaches the optical sensor 40 directly. This improves the detection accuracy of light generated when a battery 10 fails in a battery module 1 equipped with the optical sensor 40.

[0085] <Fourth embodiment> Next, the battery module 1 according to the fourth embodiment will be described, focusing mainly on the differences from the battery module 1 according to the first embodiment.

[0086] Fig. 18 is a side view of the battery module 1 according to the fourth embodiment of the present disclosure when viewed along the Y direction. Fig. 19 is a side view of the battery module 1 shown in Fig. 18 when viewed along the X direction.

[0087] 18, in the fourth embodiment, the optical sensor 40 is located in the center of the main body 721 of the lead plate 720 in a plan view of the main body 721. Specifically, the optical sensor 40 is located between the tab portion 722 in the second row and the tab portion 722 in the third row among the plurality of tab portions 722 in the third column in a plan view of the main body 721. The control board 30 further includes a support portion 731 that positions the optical sensor 40 in the center of the main body 721 in a plan view.

[0088] The second tab portions 724 are arranged in a matrix along the row and column directions. That is, the second tab portions 724 included in the tab portions 722 with the same row number among the tab portions 722 are arranged along the row direction. The second tab portions 724 included in the tab portions 722 with the same column number among the tab portions 722 are arranged along the column direction.

[0089] In this fourth embodiment, in the second tab portion 724 included in the multiple tab portions 722 in the first and second rows, the first end of the second tab portion 724 is electrically connected to the +Z side portion of the first tab portion 723, and the second end of the second tab portion 724 is electrically connected to the +Z side portion of the through hole 721a.

[0090] In addition, in the second tab portion 724 included in the multiple tab portions 722 in the third and fourth rows, the first end of the second tab portion 724 is electrically connected to the -Z side portion of the first tab portion 723, and the second end of the second tab portion 724 is electrically connected to the -Z side portion of the through hole 721a.

[0091] 20A is a side view of the lead plate 720 shown in Fig. 18 when viewed in the column direction from the optical sensor 40, and shows the second tab portions 724 included in the tab portions 722 in the third and fourth rows. Fig. 20B is a side view of the lead plate 720 shown in Fig. 19 when viewed in the column direction from the optical sensor 40, and shows the second tab portions 724 included in the tab portions 722 in the first and second rows.

[0092] Among the multiple second tab portions 724, the multiple second tab portions 724 included in the multiple tab portions 722 of the same row number have the same protrusion height H. In other words, among the multiple tab portions 722, the multiple second tab portions 724 included in the multiple tab portions 722 of the same row have the same protrusion height H.

[0093] 20B is greater than the protruding height H (H2) of the second tab portions 724 included in the first row of tab portions 722. Furthermore, the protruding height H (H4) of the second tab portions 724 included in the fourth row of tab portions 722 shown in FIG. 20A is greater than the protruding height H (H3) of the second tab portions 724 included in the third row of tab portions 722.

[0094] The protruding heights H (H2, H3) of the second tab portions 724 included in the second and third rows of the tab portions 722 are equal to each other. Note that the protruding height H (H2) of the second tab portions 724 included in the second row of the tab portions 722 and the protruding height H (H3) of the second tab portions 724 included in the third row of the tab portions 722 may be different from each other.

[0095] The protruding heights H (H1, H4) of the second tab portions 724 included in the tab portions 722 in the first and fourth rows are equal to each other. The protruding height H (H1) of the second tab portions 724 included in the tab portions 722 in the first row and the protruding height H (H4) of the second tab portions 724 included in the tab portions 722 in the fourth row may be different from each other.

[0096] By determining the protruding height H of the second tab portions 724 in this manner, the protruding height H of the second tab portions 724 increases as they move away from the optical sensor 40 in the column direction.

[0097] In the fourth embodiment, the optical sensor 40 is located at the center of the main body 721 in a plan view of the main body 721, and therefore the distance between the optical sensor 40 and the second tab portion 724 that is farthest from the optical sensor 40 among the multiple second tab portions 724 is smaller than in the first embodiment. Therefore, light generated when the second tab portion 724 melts can easily reach the optical sensor 40.

[0098] Furthermore, in the fourth embodiment, as in the first embodiment, when one of the multiple second tab portions 724 is viewed from the optical sensor 40, the protruding end T of that one second tab portion 724 does not overlap with any of the other second tab portions 724 among the multiple second tab portions 724. Therefore, light generated when the second tab portion 724 melts reaches the optical sensor 40 directly. This improves the accuracy of detecting light generated when a battery 10 fails in a battery module 1 equipped with the optical sensor 40.

[0099] The optical sensor 40 may be disposed at a position other than the center of the main body portion 721 so as to overlap with the main body portion 721. In this case, too, the protruding height H of the multiple second tab portions 724 is determined to increase with increasing distance from the optical sensor 40 in the column direction.

[0100] <First Modification of Fourth Embodiment> Next, the battery module 1 according to the first modification of the fourth embodiment will be described, focusing mainly on the differences from the battery module 1 according to the fourth embodiment described above.

[0101] 21 is a side view of the battery module 1 according to the fourth embodiment of the present disclosure as viewed along the Y direction. The lead-plate 820 includes a main body portion 821 and a plurality of tab portions 822.

[0102] As in the fourth embodiment, the optical sensor 40 is positioned between the tab portions 822 in the second row and the tab portions 822 in the third row among the plurality of tab portions 822 in the third column by the support portion 831 in a plan view of the main body portion 821. Therefore, among the column of the plurality of tab portions 822, the plurality of tab portions 822 in the third column includes the tab portion 822 that is closest to the optical sensor 40.

[0103] The second tab portions 824 included in the third column of tab portions 822, including the tab portion 822 closest to the optical sensor 40, are located at different positions in the row direction. In other words, the second tab portions 824 included in the third column of tab portions 822 do not overlap with each other when viewed along the column direction.

[0104] Of the plurality of tab portions 822 in the second column, the two second tab portions 824 included in the tab portions 822 in the second and third rows are located at the same position as each other in the row direction. Of the plurality of tab portions 822 in the second column, the two second tab portions 824 included in the tab portions 822 in the first and fourth rows are located at the same position as each other in the row direction. Furthermore, of the plurality of second tab portions 824 included in the plurality of tab portions 822 in the second column, the two second tab portions 824 included in the tab portions 822 in the second and third rows and the two second tab portions 824 included in the tab portions 822 in the first and fourth rows are located at different positions from each other in the row direction and do not overlap each other when viewed along the column direction.

[0105] Furthermore, the two second tab portions 824 included in the tab portions 822 in the second and third rows among the multiple tab portions 822 in the fourth column are located at the same position as each other in the row direction. The two second tab portions 824 included in the tab portions 822 in the first and fourth rows among the multiple tab portions 822 in the fourth column are located at the same position as each other in the row direction. Furthermore, among the multiple tab portions 822 in the fourth column, the two second tab portions 824 included in the tab portions 822 in the second and third rows and the two second tab portions 824 included in the tab portions 822 in the first and fourth rows are located at different positions from each other in the row direction and do not overlap each other when viewed along the column direction.

[0106] The second tab portions 824 included in the first column of tab portions 822 are located at the same positions in the row direction. The second tab portions 824 included in the fifth column of tab portions 822 are located at the same positions in the row direction. In other words, among the second tab portions 824 included in the first and fifth columns of tab portions 822, the second tab portions 824 with the same column number are aligned in the column direction.

[0107] Furthermore, the second and third rows of the plurality of tab portions 822 include the tab portions 822 closest to the optical sensor 40 .

[0108] Of the multiple second tab portions 824 included in the multiple tab portions 822 in the second row, including the tab portion 822 closest to optical sensor 40, three second tab portions 824 included in tab portions 822 in the first, third, and fifth columns have first ends electrically connected to the portion on the +Z side of first tab portion 823, and second ends electrically connected to the portion on the +Z side of through-hole 821a. Also, of the multiple second tab portions 824 included in the multiple tab portions 822 in the second row, two second tab portions 824 included in tab portions 822 in the second and fourth columns have first ends electrically connected to the portion on the -Z side of first tab portion 823, and second ends electrically connected to the portion on the -Z side of through-hole 821a.

[0109] Of the multiple second tab portions 824 included in the multiple tab portions 822 in the third row, including the tab portion 822 closest to optical sensor 40, three second tab portions 824 included in tab portions 822 in the first, third, and fifth columns have first ends electrically connected to the -Z side portion of first tab portion 823 and second ends electrically connected to the -Z side portion of through-hole 821a. Also, of the multiple second tab portions 824 included in the multiple tab portions 822 in the third row, two second tab portions 824 included in tab portions 822 in the second and fourth columns have first ends electrically connected to the +Z side portion of first tab portion 823 and second ends electrically connected to the +Z side portion of through-hole 821a.

[0110] Additionally, the second tab portions 824 included in the first row of tab portions 822 are aligned in the row direction. In the five second tab portions 824 included in the first row of tab portions 822, first ends of the second tab portions 824 are electrically connected to the +Z side portions of the first tab portions 823, and second ends of the second tab portions 824 are electrically connected to the +Z side portions of the through holes 821a.

[0111] The second tab portions 824 included in the fourth row of tab portions 822 are aligned in the row direction. In the five second tab portions 824 included in the fourth row of tab portions 822, first ends of the second tab portions 824 are electrically connected to the -Z side portions of the first tab portions 823, and second ends of the second tab portions 824 are electrically connected to the -Z side portions of the through holes 821a.

[0112] Fig. 22A is a side view of the lead plate 820 shown in Fig. 21 when viewed in the column direction from the optical sensor 40, and shows a plurality of second tab portions 824 included in the plurality of tab portions 822 in the third and fourth rows. Fig. 22B is a side view of the lead plate 820 shown in Fig. 21 when viewed in the column direction from the optical sensor 40, and shows a plurality of second tab portions 824 included in the plurality of tab portions 822 in the first and second rows.

[0113] The protruding height H of the second tab portions 824 included in the third column of tab portions 822, including the tab portion 822 closest to the optical sensor 40, increases as the distance from the optical sensor 40 increases in the column direction. That is, among the second tab portions 824 included in the third column of tab portions 822, the protruding height H of the second tab portion 824 included in the first row of tab portions 822 shown in FIG. 22B is higher than the protruding height H of the second tab portion 824 included in the second row of tab portions 822. Furthermore, the protruding height H of the second tab portion 824 included in the fourth row of tab portion 822 shown in FIG. 22A is higher than the protruding height H of the second tab portions 824 included in the third row of tab portions 822.

[0114] Furthermore, among the second tab portions 824 included in the third column of tab portions 822, the two second tab portions 824 included in the tab portions 822 in the second and third rows have the same protruding height H. Note that the protruding height H of the second tab portion 824 included in the tab portion 822 in the second row and the protruding height H of the second tab portion 824 included in the tab portion 822 in the third row may be different from each other.

[0115] Furthermore, among the second tab portions 824 included in the third column of tab portions 822, the two second tab portions 824 included in the tab portions 822 in the first and fourth rows have the same protruding height H. Note that the protruding height H of the second tab portions 824 included in the first row of tab portions 822 and the protruding height H of the second tab portions 824 included in the fourth row of tab portions 822 may be different from each other.

[0116] 22A and 22B, the second tab portions 824 included in the second and fourth rows of the tab portions 822 have the same protrusion height H. Furthermore, the second tab portions 824 included in the first and fifth rows of the tab portions 822 have the same protrusion height H.

[0117] Furthermore, the protruding height H of the second tab portions 824 included in the tab portions 822 in the second and third rows, including the tab portion 822 closest to the optical sensor 40, increases with increasing distance from the optical sensor 40 in the row direction.

[0118] In other words, as shown in FIG. 22B, among the multiple second tab portions 824 included in the multiple tab portions 822 in the second row, which includes the tab portion 822 closest to the optical sensor 40, the protruding height H of the second tab portion 824 included in the tab portion 822 in the third column is the shortest.

[0119] Furthermore, among the second tab portions 824 included in the second row of tab portions 822, the protruding height H of the second tab portions 824 included in the tab portions 822 in the second and fourth columns is higher than the protruding height H of the second tab portion 824 included in the tab portion 822 in the third column. The protruding heights H of the second tab portions 824 included in the tab portions 822 in the second and fourth columns are equal to each other. Note that the protruding heights H of the second tab portions 824 included in the tab portions 822 in the second and fourth columns may be different from each other.

[0120] Furthermore, among the second tab portions 824 included in the second row of tab portions 822, the protruding height H of the second tab portions 824 included in the tab portions 822 in the first and fifth columns is higher than the protruding height H of the second tab portions 824 included in the tab portions 822 in the second and fourth columns. The protruding heights H of the second tab portions 824 included in the tab portions 822 in the first and fifth columns are equal to each other. Note that the protruding heights H of the second tab portions 824 included in the tab portions 822 in the first and fifth columns may be different from each other.

[0121] Furthermore, as shown in FIG. 22A, among the multiple second tab portions 824 included in the multiple tab portions 822 in the third row, which includes the tab portion 822 closest to the optical sensor 40, the protruding height H of the second tab portion 824 included in the tab portion 822 in the third column is the shortest.

[0122] Furthermore, among the multiple second tab portions 824 included in the multiple tab portions 822 in the third row, the protruding height H of the two second tab portions 824 included in the tab portions 822 in the second and fourth columns is higher than the protruding height H of the second tab portion 824 included in the tab portions 822 in the third column. The protruding heights H of the two second tab portions 824 included in the tab portions 822 in the second and fourth columns are equal to each other. Note that the protruding heights H of the two second tab portions 824 included in the tab portions 822 in the second and fourth columns may be different from each other.

[0123] Furthermore, among the multiple second tab portions 824 included in the multiple tab portions 822 in the third row, the protruding height H of the two second tab portions 824 included in the tab portions 822 in the first and fifth columns is higher than the protruding height H of the two second tab portions 824 included in the tab portions 822 in the second and fourth columns. The protruding heights H of the two second tab portions 824 included in the tab portions 822 in the first and fifth columns are equal to each other. Note that the protruding heights H of the two second tab portions 824 included in the tab portions 822 in the first and fifth columns may be different from each other.

[0124] 22B, the protruding heights H of the three second tab portions 824 included in the tab portions 822 in the second, third, and fourth columns are equal to each other. Furthermore, the protruding heights H of the two second tab portions 824 included in the tab portions 822 in the first and fifth columns are greater than the protruding heights H of the three second tab portions 824 included in the tab portions 822 in the second, third, and fourth columns.

[0125] 22A, the protruding heights H of the three second tab portions 824 included in the tab portions 822 in the second, third, and fourth columns are equal to each other. Furthermore, the protruding heights H of the two second tab portions 824 included in the tab portions 822 in the first and fifth columns are greater than the protruding heights H of the three second tab portions 824 included in the tab portions 822 in the second, third, and fourth columns.

[0126] In this first modified example, as in the fourth embodiment described above, when one of the multiple second tab portions 824 is viewed from the optical sensor 40, the protruding end T of that one second tab portion 824 does not overlap with any of the other second tab portions 824 among the multiple second tab portions 824. Therefore, light generated when the second tab portion 824 melts reaches the optical sensor 40 directly. This improves the accuracy of detecting light generated when a battery 10 fails in a battery module 1 equipped with the optical sensor 40.

[0127] <Second Modification of Fourth Embodiment> Next, the battery module 1 according to the second modified example of the fourth embodiment will be described, focusing mainly on the differences from the battery module 1 according to the first modified example of the fourth embodiment.

[0128] 23 is a side view of a battery module 1 according to a second modified example of the fourth embodiment of the present disclosure, viewed along the Y direction. A lead plate 920 includes a main body portion 921 and multiple tab portions 922. As in the first modified example of the fourth embodiment described above, the optical sensor 40 is positioned by a support portion 931 between the second and third row tab portions 922 of the multiple tab portions 922 in the third column in a plan view of the main body portion 921.

[0129] In this second modified example, each of the multiple tab portions 922 includes one second tab portion set C made up of two second tab portions 924 of the same height. That is, each of the multiple first tab portions 923 is electrically connected to the main body portion 921 by one second tab portion set C. In this second modified example, the two second tab portions 924 included in the multiple second tab portion sets C are spaced apart by the same distance.

[0130] The positional relationship of the multiple second tab portion sets C provided with the multiple tab portions 922 shown in Figure 23 is the same as the positional relationship of the multiple second tab portions 924 according to the first modified example of the fourth embodiment shown in Figure 21.

[0131] Furthermore, the second tab portions 924 included in the third column of tab portions 922 are located at different positions in the row direction and do not overlap with each other when viewed along the column direction.

[0132] Of the multiple tab portions 922 in the second column, the two second tab portion sets C included in the tab portions 922 in the second and third rows are located at the same positions in the row direction. Of the multiple tab portions 922 in the second column, the two second tab portion sets C included in the tab portions 922 in the first and fourth rows are located at the same positions in the row direction. Furthermore, of the multiple tab portions 922 in the second column, the multiple second tab portions 924 included in the tab portions 922 in the second and third rows and the multiple second tab portions 924 included in the tab portions 922 in the first and fourth rows are located at different positions in the row direction and do not overlap with each other when viewed along the column direction.

[0133] Furthermore, the two second tab portion sets C included in the tab portions 922 in the second and third rows among the multiple tab portions 922 in the fourth column are located at the same positions in the row direction. The two second tab portion sets C included in the tab portions 922 in the first and fourth rows among the multiple tab portions 922 in the fourth column are located at the same positions in the row direction. Furthermore, among the multiple tab portions 922 in the fourth column, the multiple second tab portions 924 included in the tab portions 922 in the second and third rows and the multiple second tab portions 924 included in the tab portions 922 in the first and fourth rows are located at different positions in the row direction and do not overlap with each other when viewed along the column direction.

[0134] The second tab portion sets C included in the tab portions 922 in the first column are located at the same positions in the row direction. The second tab portion sets C included in the tab portions 922 in the fifth column are located at the same positions in the row direction. In other words, the second tab portions 924 with the same column number among the second tab portions 924 included in the tab portions 922 in the first and fifth columns are aligned in two columns in the column direction.

[0135] Fig. 24A is a side view of the lead plate 920 shown in Fig. 23 when viewed in the column direction from the optical sensor 40, and shows a plurality of second tab portion sets C included in the plurality of tab portions 922 in the third and fourth rows. Fig. 24B is a side view of the lead plate 920 shown in Fig. 23 when viewed in the column direction from the optical sensor 40, and shows a plurality of second tab portion sets C included in the plurality of tab portions 922 in the first and second rows.

[0136] The relationship between the protruding heights H of the multiple second tab portions 924 provided in the multiple second tab portion sets C included in the multiple tab portions 922 shown in Figures 24A and 24B is similar to the relationship between the protruding heights H of the multiple second tab portions 924 according to the first modified example of the above-mentioned fourth embodiment shown in Figures 22A and 22B.

[0137] In other words, the protruding height H of the second tab portions 924 of the multiple second tab portion sets C included in the multiple tab portions 922 in the third row, including the tab portion 922 closest to the optical sensor 40 shown in Figures 24A and 24B, becomes higher the further away from the optical sensor 40 in the row direction.

[0138] The protruding heights H of the second tab portions 924 included in the second tab portion sets C included in the second and fourth rows of the tab portions 922 are equal to each other. Furthermore, the protruding heights H of the second tab portions 924 included in the second tab portion sets C included in the first and fifth rows of the tab portions 922 are equal to each other.

[0139] In addition, in the multiple second tab portion sets C included in the multiple tab portions 922 in the second and third rows, including the tab portion 922 closest to the optical sensor 40, the protruding height H of the two second tab portions 924 included in the second tab portion set C that is farther from the optical sensor 40 out of two second tab portion sets C adjacent to each other in the row direction is higher than the protruding height H of the two second tab portions 924 included in the second tab portion set C that is closer to the optical sensor 40.

[0140] That is, among the plurality of second tab portion sets C included in the plurality of tab portions 922 in the second and third rows, the protruding height H of the second tab portion 924 included in the tab portion 922 in the third column is the smallest.

[0141] Furthermore, in the plurality of second tab portion sets C included in the plurality of tab portions 922 in the second and third rows, the protruding height H of the plurality of second tab portions 924 included in the tab portions 922 in the second and fourth columns is higher than the protruding height H of the plurality of second tab portions 924 included in the tab portions 922 in the third column. The protruding heights H of the plurality of second tab portions 924 included in the tab portions 922 in the second and fourth columns are equal to each other. Note that the protruding heights H of the plurality of second tab portions 624 included in the tab portions 622 in the second and fourth columns may be different from each other.

[0142] Furthermore, in the plurality of second tab portion sets C included in the plurality of tab portions 922 in the second and third rows, the protruding height H of the plurality of second tab portions 924 included in the tab portions 922 in the first and fifth columns is higher than the protruding height H of the plurality of second tab portions 924 included in the tab portions 922 in the second and fourth columns. The protruding heights H of the plurality of second tab portions 924 included in the tab portions 922 in the first and fifth columns are equal to each other. Note that the protruding heights H of the plurality of second tab portions 924 included in the tab portions 922 in the first and fifth columns may be different from each other.

[0143] In addition, in the second tab portion set C included in the plurality of tab portions 922 in the first and fourth rows, the protruding heights H of the plurality of second tab portions 924 included in the tab portions 922 in the second, third, and fourth columns are equal to one another.

[0144] Furthermore, in the second tab portion set C included in the plurality of tab portions 922 in the first and fourth rows, the protruding height H of the plurality of second tab portions 924 included in the tab portions 922 in the first and fifth columns is higher than the protruding height H of the plurality of second tab portions 924 included in the tab portions 922 in the second, third, and fourth columns. The protruding heights H of the plurality of second tab portions 924 included in the tab portions 922 in the first and fifth columns are equal to each other. Note that the protruding heights H of the plurality of second tab portions 924 included in the tab portions 922 in the first and fifth columns may be different from each other.

[0145] In this second modified example, as in the first modified example of the fourth embodiment, when one of the multiple second tab portions 924 is viewed from the optical sensor 40, the protruding end T of that one second tab portion 924 does not overlap with any of the other second tab portions 924 among the multiple second tab portions 924. Therefore, light generated when the second tab portion 924 melts reaches the optical sensor 40 directly. This improves the accuracy of detecting light generated when a battery 10 fails in a battery module 1 equipped with the optical sensor 40.

[0146] Fifth Embodiment Next, the battery module 1 according to the fifth embodiment will be described, focusing mainly on the differences from the battery module 1 according to the first embodiment.

[0147] Fig. 25 is a side view of a battery module 1 according to a fifth embodiment of the present disclosure when viewed along the Y direction. Fig. 26 is a partially enlarged view of the battery module 1 shown in Fig. 25. Fig. 27 is a side view of a lead plate 1020 shown in Fig. 25 when viewed along the column direction.

[0148] In the fifth embodiment, the protruding heights H of the multiple second tab portions 1024 are equal to one another. Furthermore, in each of the multiple tab portions 1022, the position of the second tab portion 1024 is determined as follows. That is, when an imaginary line L is defined such that a first end P1 is located at the light receiving portion 41 of the optical sensor 40 and a second end P2 is located on a ridge line R including the protruding end T of the second tab portion 1024, the second tab portion 1024 is positioned such that the multiple imaginary lines L corresponding to the multiple second tab portions 1024 do not intersect with each other other than at the first ends P1 of the imaginary line L in a plan view of the main body portion 1021.

[0149] 25 and 26, the first end P1 is located at the center of the light receiving portion 41, and the second end P2 is located at the center of the ridge R including the protruding end T of the second tab portion 1024. The first end P1 of the imaginary line L may be located at a position other than the center of the light receiving portion 41. The second end P2 of the imaginary line L may be located at a position other than the center of the ridge R including the protruding end T of the second tab portion 1024.

[0150] 25 and 27, the second tab portions 1024 included in the tab portions 1022 of the same column number are located at different positions in the row direction. In addition, in the tab portions 1022 in the first row including the tab portion 1022 closest to the optical sensor 40, a first end of the second tab portion 1024 is electrically connected to a portion on the +Z side of the first tab portion 1023, and a second end of the second tab portion 1024 is electrically connected to a portion on the +Z side of the through hole 1021a.

[0151] Furthermore, in the multiple tab portions 1022 in the second, third, and fourth rows, the first end of the second tab portion 1024 is electrically connected to the -Z side portion of the first tab portion 1023, and the second end of the second tab portion 1024 is electrically connected to the -Z side portion of the through hole 1021a.

[0152] In the fifth embodiment, as in the first embodiment, when one of the multiple second tab portions 1024 is viewed from the optical sensor 40, the protruding end T of that one second tab portion 1024 does not overlap with any of the other second tab portions 1024. Therefore, light generated when the second tab portion 1024 melts reaches the optical sensor 40 directly. This improves the accuracy of detecting light generated when a battery 10 fails in a battery module 1 equipped with the optical sensor 40.

[0153] <Modification of the Fifth Embodiment> Next, a battery module 1 according to a modification of the fifth embodiment will be described, focusing mainly on the differences from the battery module 1 according to the fifth embodiment.

[0154] 28 is a side view of the battery module 1 according to the fifth embodiment of the present disclosure as viewed along the Y direction. The lead-plate 1120 includes a main body portion 1121 and a plurality of tab portions 1122.

[0155] In this modification, the tab portion 1122 in the fourth row and third column has one second tab portion 1124. The tab portions 1122 other than the tab portion 1122 in the fourth row and third column have a second tab portion set C.

[0156] In this modified example, the positions of the second tab portion 1124 included in the tab portion 1122 in the fourth row and third column, and the positions of the multiple second tab portion sets C included in the multiple tab portions 1122 other than the tab portion 1122 in the fourth row and third column, and the spacing between the two second tab portions 1124 provided in the second tab portion set C are determined so that the multiple imaginary lines L corresponding to the multiple second tab portions 1124 do not intersect except at the first end P1 of the imaginary line L when viewed in a plane of the main body portion 1121.

[0157] Specifically, in the third column of tab portions 1122, including the tab portion 1122 closest to the optical sensor 40, the spacing between the two second tab portions 1124 of the second tab portion set C provided in the tab portions 1122 in the first, second, and third rows becomes narrower from the -Z side toward the +Z side along the Z direction. As a result, the second tab portions 1124 provided in the third column of tab portions 1122 are arranged in a V shape in a plan view of the main body portion 1121, and do not overlap each other when viewed along the column direction.

[0158] Furthermore, among the multiple second tab portion sets C included in the multiple tab portions 1122 in the second and fourth columns, the second tab portion sets C in the first and fourth rows have the same spacing between the two second tab portions 1124 and overlap when viewed along the column direction. Among the multiple second tab portion sets C included in the multiple tab portions 1122 in the second and fourth columns, the second tab portion set C in the second row has a spacing between the two second tab portions 1124 that is larger than the spacing between the two second tab portions 1124 in the second tab portion sets C in the first and fourth rows and is at a different position in the column direction from the second tab portion sets C in the first and fourth rows.

[0159] Furthermore, among the multiple second tab portion sets C included in the multiple tab portions 1122 in the second and fourth columns, the second tab portion set C in the third row has the same spacing between the two second tab portions 24 as the spacing between the two second tab portions 1124 in the second tab portion sets C in the first and fourth rows, and is located at a different position in the column direction from the second tab portion sets C in the first, second, and fourth rows. In other words, among the multiple second tab portion sets C included in the multiple tab portions 1122 in the second and fourth columns, the second tab portion sets C in the first and fourth rows overlap each other when viewed along the column direction, but do not overlap with the second tab portion sets C in the second and third rows when viewed along the column direction.

[0160] Furthermore, among the multiple second tab portion sets C included in the multiple tab portions 1122 in the 1st and 5th columns, the multiple second tab portion sets C included in the tab portions 1122 with the same column number have the same spacing between the two second tab portions 1124 and overlap when viewed along the column direction.

[0161] In addition, in the first row of multiple tab portions 1122 including the tab portion 22 closest to the optical sensor 40, the first end of the second tab portion 1124 is electrically connected to the +Z side portion of the first tab portion 1123, and the second end of the second tab portion 1124 is electrically connected to the +Z side portion of the through hole 1121a.

[0162] Furthermore, in the multiple tab portions 1122 in the second, third, and fourth rows, the first end of the second tab portion 1124 is electrically connected to the -Z side portion of the first tab portion 1123, and the second end of the second tab portion 1124 is electrically connected to the -Z side portion of the through hole 1121a.

[0163] In this modification, as in the first embodiment described above, when one of the multiple second tab portions 1124 is viewed from the optical sensor 40, the protruding end T of that one second tab portion 1124 does not overlap with any of the other second tab portions 1124 among the multiple second tab portions 1124. Therefore, light generated when the second tab portion 1124 melts reaches the optical sensor 40 directly. This improves the accuracy of detecting light generated when a battery 10 fails in a battery module 1 equipped with the optical sensor 40.

[0164] Sixth Embodiment Next, the battery module 1 according to the sixth embodiment will be described, focusing mainly on the differences from the battery module 1 according to the fourth embodiment.

[0165] 29 is a side view of the battery module 1 according to the sixth embodiment of the present disclosure as viewed along the Y direction. The lead-plate 1220 includes a main body portion 1221 and a plurality of tab portions 1222.

[0166] In the sixth embodiment, similar to the fourth embodiment, the optical sensor 40 is positioned at the center of the main body 1221 by the support portion 1231 in a plan view of the main body 1221. Also, similar to the fifth embodiment, the protruding heights H of the multiple second tab portions 1224 are equal to each other.

[0167] Furthermore, in the sixth embodiment, the positions of the second tab portions 1224 are determined so that the multiple imaginary lines L corresponding to the multiple second tab portions 1224 do not intersect with each other except at the first ends P1 of the imaginary lines L when the main body portion 1221 is viewed in plan.

[0168] In the third column of tab portions 1222, which includes the tab portion 1222 closest to the optical sensor 40, the two second tab portions 1224 included in the tab portions 1222 in the third and fourth rows do not overlap with each other when viewed along the column direction. In addition, in the third column of tab portions 1222, the two second tab portions 1224 included in the tab portions 1222 in the first and second rows do not overlap with each other when viewed along the column direction.

[0169] Furthermore, in the plurality of tab portions 1222 in the third column, the two second tab portions 1224 included in the tab portions 1222 in the second and fourth rows overlap each other when viewed along the column direction. Note that the two second tab portions 1224 included in the tab portions 1222 in the second and fourth rows do not have to overlap each other when viewed along the column direction. Furthermore, in the plurality of tab portions 1222 in the third column, the two second tab portions 1224 included in the tab portions 1222 in the first and third rows overlap each other when viewed along the column direction. Note that the two second tab portions 1224 included in the tab portions 1222 in the first and third rows do not have to overlap each other when viewed along the column direction.

[0170] Furthermore, the second tab portions 1224 included in the tab portions 1222 of the same column number in the first, second, fourth, and fifth columns are aligned in the column direction.

[0171] Furthermore, in the multiple tab portions 1222 in the first and third rows, the first end of the second tab portion 1224 is electrically connected to the portion on the +Z side of the first tab portion 1223, and the second end of the second tab portion 1224 is electrically connected to the portion on the +Z side of the through hole 1221a. In the multiple tab portions 1222 in the second and fourth rows, the first end of the second tab portion 1224 is electrically connected to the portion on the -Z side of the first tab portion 1223, and the second end of the second tab portion 1224 is electrically connected to the portion on the -Z side of the through hole 1221a.

[0172] In the sixth embodiment, as in the first embodiment, when one of the multiple second tab portions 1224 is viewed from the optical sensor 40, the protruding end T of that one second tab portion 1224 does not overlap with any of the other second tab portions 1224. Therefore, light generated when the second tab portion 1224 melts reaches the optical sensor 40 directly. This improves the accuracy of detecting light generated when a battery 10 fails in a battery module 1 equipped with the optical sensor 40.

[0173] <Modification of the Sixth Embodiment> Next, a battery module 1 according to a modification of the sixth embodiment will be described, focusing mainly on the differences from the battery module 1 according to the sixth embodiment.

[0174] 30 is a side view of the battery module 1 according to the fifth embodiment of the present disclosure as viewed along the Y direction. The lead-plate 1320 includes a main body portion 1321 and a plurality of tab portions 1322.

[0175] In this modified example, the multiple tab portions 1322 each have one second tab portion set C. In this modified example, the position of the second tab portion set C and the spacing between the two second tab portions 1324 included in the second tab portion set C are determined so that multiple imaginary lines L corresponding to the multiple second tab portions 1324 do not intersect with each other other than at first ends P1 of the imaginary lines L in a plan view of the main body portion 1321.

[0176] Specifically, among the multiple tab portions 1322 with the same column number, the two second tab portion sets C included in the tab portions 1322 in the third and fourth rows do not overlap each other when viewed along the column direction. Also, among the multiple tab portions 1322 in the third column, the two second tab portion sets C included in the tab portions 1322 in the first and second rows do not overlap each other when viewed along the column direction.

[0177] Furthermore, among the multiple tab portions 1322 with the same column number, the two second tab portion sets C included in the tab portions 1322 in the first and fourth rows overlap each other when viewed in the column direction. Note that the two second tab portion sets C included in the tab portions 1322 in the first and fourth rows do not have to overlap each other when viewed in the column direction. Furthermore, among the multiple tab portions 1322 with the same column number, the two second tab portion sets C included in the tab portions 1322 in the second and third rows overlap each other when viewed in the column direction. Note that the two second tab portion sets C included in the tab portions 1322 in the second and third rows do not have to overlap each other when viewed in the column direction.

[0178] Furthermore, in the multiple tab portions 1322 in the first and third rows and the tab portion 1322 in the second row and third column, a first end of second tab portion 1324 is electrically connected to a portion on the +Z side of first tab portion 1323, and a second end of second tab portion 1324 is electrically connected to a portion on the +Z side of through hole 1321a. In the multiple tab portions 1322 in the second and fourth rows other than tab portion 1322 in the second row and third column, a first end of second tab portion 1324 is electrically connected to a portion on the -Z side of first tab portion 1323, and a second end of second tab portion 1324 is electrically connected to a portion on the -Z side of through hole 1321a.

[0179] In this modification, as in the sixth embodiment, when one of the multiple second tab portions 1324 is viewed from the optical sensor 40, the protruding end T of the one second tab portion 1324 does not overlap with the other second tab portions 1324 of the multiple second tab portions 1324. Therefore, light generated when the second tab portion 1324 melts reaches the optical sensor 40 directly. This improves the accuracy of detecting light generated when a battery 10 fails in a battery module 1 equipped with the optical sensor 40.

[0180] Seventh Embodiment Next, the battery module 1 according to the seventh embodiment will be described, focusing mainly on the differences from the battery module 1 according to the first embodiment.

[0181] Fig. 31A is a perspective view of a battery module 1 according to a seventh embodiment of the present disclosure, as viewed from the +Y side. Fig. 31B is a perspective view of the battery module 1 shown in Fig. 31A, as viewed from the -Y side. Note that the control board 30 and the optical sensor 40 are omitted from Figs. 31A and 31B.

[0182] Hereinafter, of the two lead plates 1420, the lead plate 1420 arranged on the +Y side of the battery 10 will be referred to as "lead plate 1420a", and the lead plate 1420 arranged on the -Y side of the battery 10 will be referred to as "lead plate 1420b".

[0183] The lead plate 1420a includes a main body 1421a and a plurality of tabs 1422a. The main body 1421a has a plurality of through holes 1421aa. The lead plate 1420b includes a main body 1421b and a plurality of tabs 1422b. The main body 1421b has a plurality of through holes 1421ab.

[0184] In the seventh embodiment, the number of batteries 10 is 16. The number of batteries 10 lined up along the X direction is four. The number of batteries 10 lined up along the Z direction is four. As a result, the number of through holes 1421aa, 1421ab and the number of tab portions 1422a, 1422b are each 16. Furthermore, the number of rows and columns of the through holes 1421aa, 1421ab, and the number of rows and columns of the tab portions 1422a, 1422b are each four.

[0185] In the seventh embodiment, the main body portions 1421a and 1421b are divided. The main body portion 1421a in the seventh embodiment is divided into two, and has a first portion 1421ca and a second portion 1421da which are separate bodies.

[0186] The first portion 1421ca corresponds to one or more batteries 10 among the plurality of batteries 10. The first portion 1421ca in the seventh embodiment is electrically connected to a plurality of tab portions 1422a in the first and second rows among the plurality of tab portions 1422a, and has a plurality of through holes 1421aa corresponding to the plurality of tab portions 1422a in the first and second rows. In other words, the first portion 1421ca corresponds to eight batteries 10 electrically connected to the plurality of tab portions 1422a in the first and second rows.

[0187] The second portion 1421da corresponds to one or more batteries 10 other than the battery 10 electrically connected to the first portion 1421ca among the plurality of batteries 10. The second portion 1421da in the seventh embodiment is electrically connected to a plurality of tab portions 1422a in the third and fourth rows among the plurality of tab portions 1422a, and has a plurality of through holes 1421aa corresponding to the plurality of tab portions 1422a in the third and fourth rows. In other words, the second portion 1421da corresponds to eight batteries 10 electrically connected to the plurality of tab portions 1422a in the third and fourth rows.

[0188] Furthermore, the main body 1421b of the seventh embodiment is divided into three parts, and has a first part 1421cb, a second part 1421db, and a third part 1421eb as separate parts.

[0189] The first portion 1421cb corresponds to one or more batteries 10 of the plurality of batteries 10. The first portion 1421cb has a first row of tab portions 1422b among the plurality of tab portions 1422b and a plurality of through holes 1421ab corresponding to the first row of tab portions 1422b. In other words, the first portion 1421cb corresponds to four batteries 10 electrically connected to the first row of tab portions 1422b.

[0190] The second portion 1421db corresponds to one or more batteries 10 other than the battery 10 electrically connected to the first portion 1421cb among the plurality of batteries 10. The second portion 1421db has a plurality of tab portions 1422b in the second and third rows among the plurality of tab portions 22, and a plurality of through holes 1421ab corresponding to the plurality of tab portions 1422b in the second and third rows. In other words, the second portion 1421db corresponds to eight batteries 10 electrically connected to the plurality of tab portions 1422b in the second and third rows.

[0191] The third portion 1421eb corresponds to one or more batteries 10 other than the batteries 10 electrically connected to the first portion 1421cb and the second portion 1421db among the plurality of batteries 10. The third portion 1421eb has a fourth row of the plurality of tab portions 1422b among the plurality of tab portions 1422b and a plurality of through holes 1421ab corresponding to the fourth row of tab portions 1422b. The third portion 1421eb corresponds to four batteries 10 electrically connected to the fourth row of tab portions 1422b.

[0192] It goes without saying that the numbers of corresponding batteries 10, tab portions 1422a, 1422b, and through holes 1421aa, 1421ab in the first portion 1421ca, second portion 1421da, first portion 1421cb, second portion 1421db, and third portion 1421eb are not limited to those described above. The shapes of the first portion 1421ca, second portion 1421da, first portion 1421cb, second portion 1421db, and third portion 1421eb vary depending on the arrangement of the batteries 10, the number of batteries 10 to be electrically connected, and other factors.

[0193] As in the first embodiment, the optical sensor 40 of the seventh embodiment is located outward in the column direction from the second tab portions 1424a and 1424b in a plan view of the main bodies 1421a and 1421b. As in the fourth embodiment, the optical sensor 40 may be located in the center of the main bodies 1421a and 1421b in a plan view of the main bodies 1421a and 1421b. In this case, the second tab portions 1424a and 1424b are arranged in the same manner as in the fourth embodiment.

[0194] The lead plates 1420a, 1420b of the seventh embodiment allow for more flexible electrical connections among the multiple batteries 10 than when the main bodies 1421a, 1421b are not separated. In other words, the battery module 1 of the seventh embodiment allows for multiple-parallel and multiple-series electrical connections among the multiple batteries 10. Also, in the seventh embodiment, as in the first embodiment, when one of the multiple second tab portions 1424a, 1424b is viewed from the optical sensor 40, the protruding end T of the one second tab portion 1424a, 1424b does not overlap with the other second tab portions 1424a, 1424b. Therefore, the light generated when the second tab portions 1424a, 1424b melt down reaches the light sensor 40 directly. This improves the accuracy of detecting light generated when a battery 10 fails in a battery module 1 equipped with the light sensor 40.

[0195] <Modifications of each embodiment> It should be noted that the above-described embodiments and modifications are intended to facilitate understanding of the present disclosure and are not intended to limit the present disclosure. The present disclosure may be modified or improved without departing from the spirit thereof, and equivalents thereof are also included in the present disclosure.

[0196] 32 is a perspective view of a tab portion 1522 of a battery module 1 according to another modified example of each embodiment of the present disclosure. The tab portion 1522 includes a first tab portion 1523 and a second tab portion 1524.

[0197] The second tab portion 1524 of this other modification has a conductive portion 1524a and a notch portion 1524b at the protruding end TP, which includes the protruding end T. Due to the notch portion 1524b, the cross-sectional area of ​​the second tab portion 1524 perpendicular to the extension direction of the second tab portion 1524 is smallest at the conductive portion 1524a. Therefore, in the event of an abnormality in the battery 10 that causes an overcurrent, the protruding end TP of the second tab portion 1524 is reliably melted and emits light.

[0198] Furthermore, as described above, when one of the multiple second tab portions 1524 is viewed from the optical sensor 40, the protruding end T of that one second tab portion 1524 does not overlap with any of the other second tab portions 1524 of the multiple second tab portions 1524. Therefore, light generated when the second tab portion 1524 melts down reliably reaches the optical sensor 40 directly. Therefore, the optical sensor 40 reliably detects light generated when the second tab portion 1524 melts down. In this way, the accuracy of detecting light generated when a battery 10 fails can be improved in a battery module 1 equipped with the optical sensor 40.

[0199] <Configuration Example of the Present Disclosure> The present disclosure may also be implemented as a combination of the following configurations.

[0200] (1) a plurality of batteries having terminals; lead plates disposed opposite the terminals of the batteries and electrically connected to each of the plurality of batteries; an optical sensor; The lead plate is a plate-shaped main body portion having a plurality of through holes that overlap with the terminals of the battery in a plan view; and a plurality of tab portions, Each of the plurality of tab portions includes: a plate-shaped first tab portion located inside the periphery of the through hole in a plan view of the main body portion and electrically connected to a terminal of the battery; a second tab portion that electrically connects the first tab portion and the main body portion, the second tab portion has a first end electrically connected to a portion of a periphery of the first tab portion and a second end electrically connected to a portion of a periphery of the through hole, and is shaped to protrude from the main body portion to a side opposite to the battery side; the optical sensor is located on the opposite side of the main body from the battery when viewed from the side of the main body; Battery module.

[0201] (2) a cross-sectional area of ​​the second tab portion perpendicular to the extending direction of the second tab portion is smaller than a cross-sectional area of ​​the first tab portion along the thickness direction; The battery module according to (1).

[0202] (3) the second tab portion protrudes from the main body portion to the side opposite to the battery side and has a U-shaped cross section that is open to the battery side; The battery module according to (1) or (2).

[0203] (4) when one of the plurality of second tab portions is viewed from the optical sensor, a protruding end of the one second tab portion does not overlap with other second tab portions other than the one second tab portion among the plurality of second tab portions; A battery module according to any one of (1) to (3).

[0204] (5) the plurality of second tab portions include two second tab portions that are different in distance from the optical sensor; Of the two second tab portions, a protruding height of the second tab portion that is farther from the optical sensor is greater than a protruding height of the second tab portion that is farther from the optical sensor. A battery module according to any one of (1) to (4).

[0205] (6) the plurality of tab portions are arranged in a matrix along both row and column directions in a plan view of the main body portion, The protruding height of the plurality of second tab portions increases as the second tab portions are farther from the optical sensor in the column direction. A battery module according to any one of (1) to (5).

[0206] (7) the protrusion heights of the second tab portions included in the tab portions in the same row among the plurality of tab portions are equal to each other; (6) The battery module according to (6).

[0207] (8) The protruding height of the plurality of second tab portions increases as the second tab portions are farther away from the optical sensor in the row direction. (6) The battery module according to (6).

[0208] (9) the second tab portions included in the plurality of tab portions in the same column among the plurality of tab portions are located at different positions from each other in the row direction; A battery module according to any one of (6) to (8).

[0209] (10) The protruding heights of the plurality of second tab portions are equal to each other. (4) The battery module according to (4).

[0210] (11) the optical sensor is located outward in the column direction from the second tab portions in a plan view of the main body portion. A battery module according to any one of (6) to (9).

[0211] (12) the optical sensor is located at the center of the main body in a plan view of the main body; A battery module according to any one of (1) to (10).

[0212] (13) The plurality of tab portions include the tab portion having one of the first tab portions and two of the second tab portions. A battery module according to any one of (1) to (12).

[0213] (14) The main body portion is a first portion corresponding to one or more of the plurality of batteries; a second section that is separate from the first section and corresponds to one or more of the plurality of batteries other than the battery electrically connected to the first section; A battery module according to any one of (1) to (13).

[0214] (15) The second tab portion has a notch portion at a protruding end portion. A battery module according to any one of (1) to (14). [Explanation of symbols]

[0215] 1 Battery Module 10 batteries 11 terminals 11a Positive terminal (terminal) 11b Negative terminal (terminal) 20 Reed plate 21 Main body 21a Through hole 22 Tab section 23 First tab section 24 Second tab section 30 Control board 40 Optical Sensor 1421ca,1421cb 1st part 1421da,1421db 2nd part 1524b Notch H Projection height T protruding end TP protruding end

Claims

1. a plurality of batteries having terminals; lead plates disposed opposite the terminals of the batteries and electrically connected to each of the plurality of batteries; an optical sensor; The lead plate is a plate-shaped main body portion having a plurality of through holes that overlap with the terminals of the battery in a plan view; and a plurality of tab portions, Each of the plurality of tab portions includes: a plate-shaped first tab portion located inside a periphery of the through hole in a plan view of the main body portion and electrically connected to a terminal of the battery; a second tab portion electrically connecting the first tab portion and the main body portion, the second tab portion has a first end electrically connected to a portion of a periphery of the first tab portion and a second end electrically connected to a portion of a periphery of the through hole, and has a shape that protrudes from the main body portion to a side opposite to the battery side, the optical sensor is located on the opposite side of the main body from the battery when viewed from the side of the main body; Battery module.

2. a cross-sectional area of ​​the second tab portion perpendicular to the extending direction of the second tab portion is smaller than a cross-sectional area of ​​the first tab portion along the thickness direction; The battery module according to claim 1 .

3. the second tab portion protrudes from the main body portion toward the opposite side to the battery side and has a U-shaped cross section that is open toward the battery side; The battery module according to claim 1 .

4. when one of the plurality of second tab portions is viewed from the optical sensor, a protruding end of the one second tab portion does not overlap with any of the other second tab portions other than the one second tab portion among the plurality of second tab portions; The battery module according to claim 1 .

5. the plurality of second tab portions include two second tab portions that are different in distance from the optical sensor; a protruding height of the second tab portion that is located at a longer distance from the optical sensor than a protruding height of the second tab portion that is located at a shorter distance from the optical sensor; The battery module according to claim 1 .

6. the plurality of tab portions are arranged in a matrix along both row and column directions in a plan view of the main body portion, The protruding height of the plurality of second tab portions increases as the second tab portions are farther from the optical sensor in the column direction. The battery module according to claim 1 .

7. the protrusion heights of the second tab portions included in the tab portions in the same row among the plurality of tab portions are equal to each other; The battery module according to claim 6 .

8. The protruding height of the plurality of second tab portions increases as the second tab portions are farther from the optical sensor in the row direction. The battery module according to claim 6 .

9. the second tab portions included in the plurality of tab portions in the same column among the plurality of tab portions are located at different positions from each other in the row direction; The battery module according to claim 6 .

10. The protruding heights of the plurality of second tab portions are equal to each other. The battery module according to claim 4 .

11. the optical sensor is located outward in the column direction from the second tab portions in a plan view of the main body portion; The battery module according to claim 6 .

12. The optical sensor is located at a center of the main body in a plan view of the main body. The battery module according to claim 1 .

13. the plurality of tab portions include a tab portion having one of the first tab portions and a plurality of the second tab portions; The battery module according to claim 1 .

14. The main body portion is a first portion corresponding to one or more of the plurality of batteries; a second portion that is separate from the first portion and corresponds to one or more of the plurality of batteries other than the battery electrically connected to the first portion; The battery module according to claim 1 .

15. The second tab portion has a notch portion at a protruding end portion. The battery module according to claim 1 .

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