Voltage detection device and battery module

Abstract

To suppress a damage of a voltage detection device due to heat generation of a busbar.SOLUTION: A voltage detection device 300 includes: a voltage detection unit 310 that detects voltage of at least one battery cell 100; a right busbar 340 at least a part of which electrically connects at least one battery cell 100 to an external device; and a right attachment body 360 to which the right busbar 340 is attached. The right attachment body 360 has heat resistance.SELECTED DRAWING: Figure 1

Description

Technical Field

[0001] The present invention relates to a voltage detection device and a battery module.

Background Art

[0002] A battery module such as a lithium-ion secondary battery includes a plurality of stacked battery cells. In such a battery module, a plurality of battery cells are electrically connected to each other by a positive electrode lead and a negative electrode lead drawn from the battery cells. Further, a plurality of battery cells connected in parallel may be connected in series to a plurality of other battery cells connected in parallel.

[0003] Patent Document 1 describes an example of a battery module. In this example, the positive electrode lead and the negative electrode lead of each battery cell are electrically connected via a bus bar.

[0004] Patent Document 2 describes an example of a method for manufacturing a battery module. In this example, the positive electrode lead of a single battery cell and the negative electrode lead of another single battery cell are joined by ultrasonic bonding. Also, the lead portion is folded back between different battery cells.

Prior Art Documents

Patent Documents

[0005]

Patent Document 1

Patent Document 2

Summary of the Invention

Problems to be Solved by the Invention

[0006] For example, as described in Patent Document 2, the lead portion may be folded between different battery cells. In this case, in order to detect the voltage of each battery cell, a voltage detection device having a voltage detection portion connected to each lead portion of each battery cell may be used. This voltage detection device may have a bus bar for electrically connecting a plurality of battery cells to an external device. However, under certain conditions such as when a large current flows through the bus bar, for example, the bus bar may generate heat at a relatively high temperature. Therefore, the voltage detection device may be damaged by the heat generated by the bus bar.

[0007] An example of the object of the present invention is to suppress damage to the voltage detection device due to heat generation of the bus bar. Other objects of the present invention will become apparent from the description herein.

Means for Solving the Problems

[0008] One aspect of the present invention is a voltage detection portion for detecting the voltage of at least one battery cell, a bus bar at least a part of which electrically connects the at least one battery cell to an external device, a first attachment body to which the bus bar is attached, and the first attachment body has heat resistance, a voltage detection device.

[0009] Another aspect of the present invention is the voltage detection device, the at least one battery cell, and a battery module comprising the same.

Advantages of the Invention

[0010] According to the above aspect of the present invention, damage to the voltage detection device due to heat generation of the bus bar can be suppressed.

Brief Description of the Drawings

[0011]

Figure 1

Figure 2

Mode for Carrying Out the Invention

[0012] Hereinafter, embodiments and modified examples of the present invention will be described with reference to the drawings. In all the drawings, the same components are denoted by the same reference numerals, and the description thereof will be omitted as appropriate.

[0013] In this specification, ordinal numbers such as "first", "second", and "third" are given for the sole purpose of simply distinguishing configurations with the same name, unless otherwise specified, and do not mean specific features of the configuration (for example, order or importance).

[0014] In this specification, when A and B are substantially equal, it means not only that A and B are exactly equal, but also, for example, that A is 90% or more and 110% or less of B, or that B is 90% or more and 110% or less of A.

[0015] FIG. 1 is a front exploded perspective view of a battery module 10 according to an embodiment. FIG. 2 is a side view of a part of a plurality of battery cells 100 according to an embodiment.

[0016] In FIGS. 1 and 2, a first direction X is a direction parallel to the longitudinal direction of the battery cell 100. A second direction Y is orthogonal to the first direction X and is a direction parallel to the thickness direction of the battery cell 100. A third direction Z is orthogonal to both the first direction X and the second direction Y and is a direction parallel to the short-side direction of the battery cell 100. An arrow indicating the first direction X, the second direction Y, or the third direction Z indicates that the direction from the base end to the tip of the arrow is the positive direction of the direction indicated by the arrow, and the direction from the tip to the base end of the arrow is the negative direction of the direction indicated by the arrow. The white circle with a black dot indicating the third direction Z indicates that the direction from the front to the back of the paper surface is the positive direction of the third direction Z, and the direction from the back to the front of the paper surface is the negative direction of the third direction Z.

[0017] In FIGS. 1 and 2, the positive direction of the first direction X is parallel to the direction from the front surface to the rear surface of the battery module 10, and the negative direction of the first direction X is the direction from the rear surface to the front surface of the battery module 10. Also, the positive direction of the second direction Y is parallel to the direction from right to left when viewed from the front surface of the battery module 10, and the negative direction of the second direction Y is parallel to the direction from left to right when viewed from the front surface of the battery module 10. Further, the positive direction of the third direction Z is parallel to the direction from bottom to top in the vertical direction, and the negative direction of the third direction Z is parallel to the direction from top to bottom in the vertical direction. Note that the relationship among the first direction X, the second direction Y, the third direction Z, and the vertical direction is not limited to the above-described example. The relationship among the first direction X, the second direction Y, the third direction Z, and the vertical direction varies according to the arrangement of the battery module 10. For example, the battery module 10 may be arranged such that the first direction X or the second direction Y is parallel to the vertical direction.

[0018] Referring to FIGS. 1 and 2, the battery module 10 will be described.

[0019] The battery module 10 includes a plurality of battery cells 100, a container 200, and a voltage detection device 300. The voltage detection device 300 has a plurality of voltage detection units 310, a plurality of voltage detection lines 320, a first wiring 322, a second wiring 324, a connector 330, a right bus bar 340, a left bus bar 350, a right attachment 360, a left attachment 370, and a central attachment 380. Note that the battery module 10 is provided with a voltage detection device (not shown) in the same manner on the positive direction side of the first direction X of the plurality of cell groups 100G stacked in the second direction Y as on the negative direction side of the first direction X of the plurality of cell groups 100G stacked in the second direction Y.

[0020] The plurality of battery cells 100 are stacked in the second direction Y. Each battery cell 100 has an exterior member 102. Each battery cell 100 is provided with a positive electrode lead 110 and a negative electrode lead 120.

[0021] The exterior member 102 houses a positive electrode, a negative electrode, and a separator (not shown) together with an electrolytic solution (not shown). In one example, the positive electrode, the negative electrode, and the separator are laminated in the second direction Y within the exterior member 102. Alternatively, the positive electrode, the negative electrode, and the separator may be wound within the exterior member 102.

[0022] The positive electrode lead 110 is drawn out from one end on the positive direction side and the negative direction side in the first direction X of the exterior member 102. The positive electrode lead 110 is electrically connected to the positive electrode within the exterior member 102. In one example, the positive electrode lead 110 is made of a metal such as aluminum.

[0023] The negative electrode lead 120 is drawn out from the other end on the positive direction side and the negative direction side in the first direction X of the exterior member 102. The negative electrode lead 120 is electrically connected to the negative electrode within the exterior member 102. In one example, the negative electrode lead 120 is made of a metal different from the metal constituting the positive electrode lead 110, for example, copper.

[0024] The plurality of battery cells 100 laminated in the second direction Y includes a plurality of cell groups 100G laminated in the second direction Y. Each cell group 100G includes a plurality of battery cells 100 connected in parallel adjacent to each other in the second direction Y. The plurality of cell groups 100G are connected in series from the cell group 100G located at the end on the negative direction side in the second direction Y among the plurality of cell groups 100G to the cell group 100G located at the end on the positive direction side in the second direction Y among the plurality of cell groups 100G.

[0025] The details of the cell group 100G will be described with reference to FIG. 2. FIG. 2 shows the end on the negative direction side in the first direction X of the first cell group 100Ga and the second cell group 100Gb among the plurality of cell groups 100G.

[0026] The first cell group 100Ga includes a plurality of battery cells 100 connected in parallel adjacent to each other in the second direction Y, that is, a plurality of first battery cells 100a. The second cell group 100Gb includes a plurality of battery cells 100 connected in parallel adjacent to each other in the second direction Y, that is, a plurality of second battery cells 100b.

[0027] The first cell group 100Ga is provided with a plurality of positive electrode leads 110 bundled together. The second cell group 100Gb is provided with a plurality of negative electrode leads 120 bundled together. The plurality of positive electrode leads 110 of the first cell group 100Ga and the plurality of positive electrode leads 110 (not shown in FIG. 2) of the second cell group 100Gb are directed in opposite directions with respect to the first direction X. The plurality of negative electrode leads 120 (not shown in FIG. 2) of the first cell group 100Ga and the plurality of negative electrode leads 120 of the second cell group 100Gb are directed in opposite directions with respect to the first direction X.

[0028] At least a part of the plurality of positive electrode leads 110 of the first cell group 100Ga, specifically the tip part, and at least a part of the plurality of negative electrode leads 120 of the second cell group 100Gb, specifically the tip part, are joined to each other. The plurality of positive electrode leads 110 of the first cell group 100Ga and the plurality of negative electrode leads 120 of the second cell group 100Gb are folded back from one of the first cell group 100Ga and the second cell group 100Gb via the at least a part of the plurality of positive electrode leads 110 of the first cell group 100Ga and the at least a part of the plurality of negative electrode leads 120 of the second cell group 100Gb over the first cell group 100Ga and the second cell group 100Gb. Therefore, the first cell group 100Ga and the second cell group 100Gb can be electrically connected without using a conductive member such as a bus bar. In this case, compared with the case where a conductive member such as a bus bar is used, the structure for connecting the first cell group 100Ga and the second cell group 100Gb in series can be simplified.

[0029] The lead part 150 including a plurality of positive electrode leads 110 of the first cell group 100Ga and a plurality of negative electrode leads 120 of the second cell group 100Gb includes a first region 152, a second region 154, and a third region 156. The lead part 150 is folded between different battery cells 100, specifically, between the first cell group 100Ga and the second cell group 100Gb. The first region 152 is a region where the distance in the second direction Y between the plurality of positive electrode leads 110 of the first cell group 100Ga decreases as it moves away from the first cell group 100Ga. The second region 154 is a region where the distance in the second direction Y between the plurality of negative electrode leads 120 of the second cell group 100Gb decreases as it moves away from the second cell group 100Gb. The third region 156 is located between the first region 152 and the second region 154, and is a region where the plurality of positive electrode leads 110 of the first cell group 100Ga and the plurality of negative electrode leads 120 bundled together are joined to each other.

[0030] As shown in FIG. 2, the lengths from the outer packaging material 102 of the two positive electrode leads 110 located at both ends in the second direction Y among the plurality of positive electrode leads 110 of the first cell group 100Ga to the first bending part 158a between the first region 152 and the third region 156 are substantially equal. In this case, compared with the case where the lengths of the two positive electrode leads 110 are different from each other, the occurrence of bending of one of the two positive electrode leads 110 can be suppressed. Note that the lengths of the two positive electrode leads 110 may be different from each other.

[0031] As shown in FIG. 2, the lengths from the outer packaging material 102 of the two negative electrode leads 120 located at both ends in the second direction Y among the plurality of negative electrode leads 120 of the second cell group 100Gb to the second bending part 158b between the second region 154 and the third region 156 are substantially equal. In this case, compared with the case where the lengths of the two negative electrode leads 120 are different from each other, the occurrence of bending of one of the two negative electrode leads 120 can be suppressed. Note that the lengths of the two negative electrode leads 120 may be different from each other.

[0032] As shown in FIG. 2, the third region 156 between the first bent portion 158a and the second bent portion 158b is flat and parallel to the second direction Y and the third direction Z. In this case, compared with the case where the third region 156 is non-flat such as being curved, it becomes easier to join the voltage detection unit 310 described later to the third region 156. Note that the third region 156 may be non-flat such as being curved.

[0033] Referring to FIGS. 1 and 2 again, the battery module 10 will be described.

[0034] As shown in FIG. 1, in a region where a plurality of positive electrode leads 110 and a plurality of negative electrode leads 120 among the respective lead portions 150 located on the negative direction side in the first direction X of the plurality of cell groups 100G stacked in the second direction Y are joined to each other, the plurality of negative electrode leads 120 are located on the negative direction side in the first direction X with respect to the plurality of positive electrode leads 110. However, the structure of each lead portion 150 is not limited to the example shown in FIG. 1. Note that also on the positive direction side in the first direction X of the plurality of cell groups 100G stacked in the second direction Y, a plurality of lead portions 150 are provided in the same manner as on the negative direction side in the first direction X of the plurality of cell groups 100G stacked in the second direction Y.

[0035] The container 200 houses a plurality of cell groups 100G stacked in the second direction Y. The container 200 has a right cover member 210, a left cover member 220, a lower cover member 230, and an upper cover member 240. The right cover member 210 covers the negative direction side in the second direction Y of the plurality of cell groups 100G stacked in the second direction Y. The left cover member 220 covers the positive direction side in the second direction Y of the plurality of cell groups 100G stacked in the second direction Y. The lower cover member 230 covers the negative direction side in the third direction Z of the plurality of cell groups 100G stacked in the second direction Y. The upper cover member 240 covers the positive direction side in the third direction Z of the plurality of cell groups 100G stacked in the second direction Y. Further, the container 200 has a front cover member (not shown) that covers the negative direction side in the first direction X of the plurality of cell groups 100G stacked in the second direction Y and the voltage detection device 300. Furthermore, the container 200 has a rear cover member (not shown) that covers the positive direction side in the first direction X of the plurality of cell groups 100G stacked in the second direction Y and a voltage detection device (not shown) provided on the positive direction side in the first direction X of the plurality of cell groups 100G stacked in the second direction Y. In the example shown in FIG. 1, the front cover member is removed.

[0036] Each of the plurality of voltage detection units 310 is provided for each of the plurality of lead units 150. Each of the plurality of voltage detection units 310 detects the voltage of each of the plurality of lead units 150. Each voltage detection unit 310 is electrically connected to at least one of the plurality of positive electrode leads 110 and the plurality of negative electrode leads 120 in each lead unit 150. Each voltage detection unit 310 is joined to the plurality of positive electrode leads 110 and the plurality of negative electrode leads 120 in the lead unit 150, for example, by laser welding.

[0037] The voltage detection unit 310 is provided on a flat portion of the lead unit 150 parallel to the second direction Y and the third direction Z. In this case, it is easier to join the voltage detection unit 310 to the lead unit 150 as compared with the case where the voltage detection unit 310 is provided on a non-flat portion such as a bent portion of the lead unit 150 or the case where the entire lead unit 150 is curved.

[0038] The voltage detection unit 310 may be movable in at least one of a direction approaching the lead unit 150 and a direction away from the lead unit 150. In this case, by moving the voltage detection unit 310 in the first direction X, the voltage detection unit 310 can be arranged at an appropriate position with respect to the lead unit 150 in the first direction X.

[0039] In one example, the voltage detection unit 310 includes the same material as the portion of the lead unit 150 that comes into contact with the voltage detection unit 310, that is, the material included in the negative electrode lead 120. In this example, compared with the case where the material included in the voltage detection unit 310 is different from the material included in the negative electrode lead 120, the material included in the voltage detection unit 310 is more easily joined to the negative electrode lead 120.

[0040] One end of each of the plurality of voltage detection lines 320 is electrically connected to each of the plurality of voltage detection units 310. Also, the other ends of the plurality of voltage detection lines 320 are electrically connected to the connector 330. Therefore, the plurality of voltage detection units 310 are electrically connected to the connector 330 via the plurality of voltage detection lines 320.

[0041] The right bus bar 340 includes a first extension body 342 and a second extension body 344. Each of the first extension body 342 and the second extension body 344 is made of, for example, copper or aluminum. The first extension body 342 and the second extension body 344 extend in different directions from each other. Specifically, the first extension body 342 extends substantially parallel to the second direction Y. The second extension body 344 extends substantially parallel to the third direction Z. The end portion on the negative direction side of the first extension body 342 in the second direction Y and the end portion on the positive direction side of the second extension body 344 in the third direction Z intersect substantially at a right angle. Therefore, when viewed from the first direction X, the right bus bar 340 has a substantially L-shaped configuration.

[0042] The first extending body 342 functions as a terminal for electrically connecting a plurality of cell groups 100G to an external device (not shown). Specifically, the second extending body 344 is electrically connected to the terminal positive electrode lead 110T. The terminal positive electrode lead 110T is the positive electrode lead 110 drawn out to the negative direction side in the first direction X of the cell group 100G located at the negative direction side in the second direction Y among the plurality of cell groups 100G. The first extending body 342 is provided with a first fastening hole 346. A fixture (not shown) for fixing an external device (not shown) is fixed to the first fastening hole 346.

[0043] Note that the direction in which the terminal positive electrode lead 110T is drawn out can be changed according to the total number of the plurality of cell groups 100G stacked in the second direction Y. For example, the terminal positive electrode lead 110T may be the positive electrode lead 110 drawn out to the positive direction side in the first direction X of the cell group 100G located at the negative direction side in the second direction Y among the plurality of cell groups 100G. In this example, the right bus bar 340 is provided on the positive direction side in the first direction X of the plurality of cell groups 100G in the same manner as the terminal positive electrode lead 110T.

[0044] The first extending body 342 is electrically connected to the connector 330 via the first wiring 322. Specifically, one end of the first wiring 322 is attached to the first extending body 342 by a first fixture 348 provided on the first extending body 342. In the embodiment, the first fixture 348 is a screw. The first fixture 348 attaches one end of the first wiring 322 to the first extending body 342 and attaches the first extending body 342 to the right mounting body 360. The other end of the first wiring 322 is electrically connected to the connector 330. The first wiring 322 functions as a voltage detection line of the right bus bar 340.

[0045] The left bus bar 350 includes a third extending body 352 and a fourth extending body 354. Each of the third extending body 352 and the fourth extending body 354 is made of, for example, copper or aluminum. The third extending body 352 and the fourth extending body 354 extend in different directions from each other. Specifically, the third extending body 352 extends substantially parallel to the second direction Y. The fourth extending body 354 extends substantially parallel to the third direction Z. The end of the third extending body 352 on the positive side in the second direction Y and the end of the fourth extending body 354 on the positive side in the third direction Z intersect substantially at a right angle. Therefore, when viewed from the first direction X, the left bus bar 350 is substantially in an L shape.

[0046] The third extending body 352 functions as a terminal for electrically connecting a plurality of cell groups 100G to an external device (not shown). Specifically, the fourth extending body 354 is electrically connected to the terminal negative electrode lead 120T. The terminal negative electrode lead 120T is the negative electrode lead 120 drawn out to the negative side in the first direction X of the cell group 100G located at the end on the positive side in the second direction Y among the plurality of cell groups 100G. A second fastening hole 356 is provided in the third extending body 352. A fixture (not shown) for fixing an external device (not shown) is fixed to the second fastening hole 356.

[0047] Note that the direction in which the terminal negative electrode lead 120T is drawn out can be changed according to the total number of the plurality of cell groups 100G stacked in the second direction Y. For example, the terminal negative electrode lead 120T may be the negative electrode lead 120 drawn out to the positive side in the first direction X of the cell group 100G located at the end on the positive side in the second direction Y among the plurality of cell groups 100G. In this example, the left bus bar 350 is provided on the positive side in the first direction X of the plurality of cell groups 100G in the same manner as the terminal negative electrode lead 120T.

[0048] The third extending body 352 is electrically connected to the connector 330 via the second wiring 324. Specifically, one end of the second wiring 324 is attached to the third extending body 352 by a second fixture 358 provided on the third extending body 352. In the embodiment, the second fixture 358 is a screw. The second fixture 358 attaches one end of the second wiring 324 to the third extending body 352 and also attaches the third extending body 352 to the left mounting body 370. The other end of the second wiring 324 is electrically connected to the connector 330. The second wiring 324 functions as a voltage detection line of the left bus bar 350.

[0049] The right mounting body 360 is attached to the right cover member 210. A right bus bar 340 is attached to the right mounting body 360. Specifically, at least a part of the second extending body 344 is inserted into the right mounting body 360 in the third direction Z. Also, as described above, the first extending body 342 is attached to the right mounting body 360 by the first fixture 348. However, the method of attaching the right bus bar 340 to the right mounting body 360 is not limited to this example.

[0050] The left mounting body 370 is attached to the left cover member 220. A left bus bar 350 is attached to the left mounting body 370. Specifically, at least a part of the fourth extending body 354 is inserted into the left mounting body 370 in the third direction Z. Also, as described above, the third extending body 352 is attached to the left mounting body 370 by the second fixture 358. However, the method of attaching the left bus bar 350 to the left mounting body 370 is not limited to this example.

[0051] The central mounting body 380 is attached to the upper cover member 240. The central mounting body 380 extends substantially parallel to the second direction Y. The end portion of the central mounting body 380 on the negative side in the second direction Y is connected to the end portion of the right mounting body 360 on the positive side in the third direction Z. The end portion of the central mounting body 380 on the positive side in the second direction Y is connected to the end portion of the left mounting body 370 on the positive side in the third direction Z.

[0052] A plurality of voltage detection units 310, a plurality of voltage detection lines 320, a first wiring 322, a second wiring 324, and a connector 330 are attached to the central attachment body 380. Specifically, the end portion on the positive direction side in the third direction Z of each voltage detection unit 310 is held by the central attachment body 380. The plurality of voltage detection lines 320, the first wiring 322, and the second wiring 324 are arranged along a groove provided on the negative direction side in the first direction X of the central attachment body 380. The connector 330 is provided approximately at the center in the second direction Y of the central attachment body 380. However, the attachment method of the plurality of voltage detection units 310, the plurality of voltage detection lines 320, the first wiring 322, the second wiring 324, and the connector 330 to the central attachment body 380 is not limited to this example.

[0053] The right mounting body 360 has heat resistance. Specifically, the right mounting body 360 contains a heat-resistant material. As the heat-resistant material, a material having a melting point higher than that of polypropylene (PP) is preferable, a material having a melting point of 200°C or higher is preferable, and examples thereof include polybutylene terephthalate and modified polyphenylene ether. The right mounting body 360 may contain a single heat-resistant material exemplified herein, or may contain a plurality of types of heat-resistant materials exemplified herein. A large current may flow through the right bus bar 340. Under certain conditions such as a large current flowing through the right bus bar 340, the right bus bar 340 may generate heat at a relatively high temperature. However, in the embodiment, damage to the right mounting body 360 due to heat generation of the right bus bar 340 can be suppressed as compared with the case where the right mounting body 360 does not have heat resistance. Further, as described above, a part of the right bus bar 340 functions as a terminal for electrically connecting a plurality of cell groups 100G to an external device (not shown). Therefore, the right bus bar 340 and the terminal of the external device (not shown) are connected by a fastening member (not shown) such as a screw provided in the first fastening hole 346. At this time, a relatively large load may be applied to the right mounting body 360 due to the torque when attaching the terminal of the external device (not shown) to the right bus bar 340. Therefore, both heat resistance and strength may be required for the right mounting body 360. For this reason, by including a fiber material such as glass fiber in the heat-resistant material of the right mounting body 360, both heat resistance and strength of the right mounting body 360 can be achieved.

[0054] The left mounting body 370 has heat resistance. Specifically, the left mounting body 370 contains a heat-resistant material. Examples of the heat-resistant material of the left mounting body 370 are the same materials as those exemplified in the description of the right mounting body 360. Similar to the right bus bar 340, a large current may flow through the left bus bar 350. Under certain conditions such as a large current flowing through the left bus bar 350, the left bus bar 350 may generate heat at a relatively high temperature. However, in the embodiment, damage to the left mounting body 370 due to heat generation of the left bus bar 350 can be suppressed as compared with the case where the left mounting body 370 does not have heat resistance. Also, similar to the heat-resistant material contained in the right mounting body 360, the heat-resistant material contained in the left mounting body 370 may contain a fiber material.

[0055] The heat resistance of the central mounting body 380 may be lower than at least one of the heat resistance of the right mounting body 360 and the heat resistance of the left mounting body 370. This is because the plurality of voltage detection units 310, the plurality of voltage detection lines 320, the first wiring 322, the second wiring 324, and the connector 330 attached to the central mounting body 380 are less likely to generate heat at a high temperature as compared with the right bus bar 340 and the left bus bar 350. Examples of the material used for the central mounting body 380 include polypropylene (PP). The cost of materials with relatively high heat resistance is relatively high. Therefore, when the heat resistance of the central mounting body 380 is lower than at least one of the heat resistance of the right mounting body 360 and the heat resistance of the left mounting body 370, the cost of the central mounting body 380 can be reduced as compared with the case where the heat resistance of the central mounting body 380 is equal to or higher than both the heat resistance of the right mounting body 360 and the heat resistance of the left mounting body 370. However, the central mounting body 380 may have heat resistance in the same manner as the right mounting body 360 and the left mounting body 370.

[0056] As described above, whether the terminal positive electrode lead 110T and the terminal negative electrode lead 120T are drawn out to the positive direction side of the first direction X or the negative direction side of the first direction X changes depending on the total number of the plurality of cell groups 100G laminated in the second direction Y. Therefore, for example, the terminal positive electrode lead 110T and the right bus bar 340 may be provided on the negative direction side of the first direction X and the negative direction side of the second direction Y of the plurality of cell groups 100G, and the terminal negative electrode lead 120T and the left bus bar 350 may be provided on the positive direction side of the first direction X and the positive direction side of the second direction Y of the plurality of cell groups 100G. In this example, the right mounting body 360 is provided on the negative direction side of the first direction X and the negative direction side of the second direction Y of the plurality of cell groups 100G in the same manner as the terminal positive electrode lead 110T and the right bus bar 340, and the left mounting body 370 is provided on the positive direction side of the first direction X and the positive direction side of the second direction Y of the plurality of cell groups 100G in the same manner as the terminal negative electrode lead 120T and the left bus bar 350.

[0057] As described above, the embodiments and modified examples of the present invention have been described with reference to the drawings. These are examples of the present invention, and various configurations other than the above can also be adopted.

[0058] For example, in the embodiment, two battery cells 100 connected in parallel are connected in series to two other battery cells 100 connected in parallel. However, three or more battery cells 100 connected in parallel may be connected in series to three or more other battery cells 100 connected in parallel.

[0059] Also, in the embodiment, the voltage detection device 300 is used to detect the voltage of the lead portion 150 including the plurality of positive electrode leads 110 and the plurality of negative electrode leads 120. However, the voltage detection device 300 can also be used to detect the voltage of the lead portion 150 including a single positive electrode lead 110 and a single negative electrode lead 120. Examples of reference configurations are described below. 1. A voltage detection unit that detects the voltage of at least one battery cell, A bus bar that electrically connects at least a part of the at least one battery cell to an external device, A first attachment body to which the bus bar is attached, Comprising, A voltage detection device in which the first attachment body has heat resistance. 2. Further comprising a second attachment body to which the voltage detection unit is attached, The voltage detection device according to 1., wherein the heat resistance of the second attachment body is lower than the heat resistance of the first attachment body. 3. The first attachment body contains at least one of polybutylene terephthalate and modified polyphenylene ether, The voltage detection device according to 2., wherein the second attachment body contains polypropylene. 4. The voltage detection device according to any one of 1. to 3., wherein the first attachment body contains a fiber material. 5. A voltage detection device according to any one of 1. to 4., The at least one battery cell, A battery module comprising.

Explanation of Symbols

[0060] 10 Battery module 100 Battery cell 100G Cell group 100Ga First cell group 100Gb Second cell group 100a First battery cell 100b Second battery cell 102 Exterior material 110 Positive electrode lead 110T Terminal positive electrode lead 120 Negative electrode lead 120T Terminal negative electrode lead 150 Lead part 152 First region 154 Second region 156 Third region 158a First bent part 158b Second bent part 200 Container 210 Right cover member 220 Left cover member 230 Bottom cover member 240 Top cover member 300 Voltage detection device 310 Voltage detection part 320 Voltage detection line 322 First wiring 324 Second wiring 330 Connector 340 Right bus bar 342 First extending body 344 Second extended body 346 First fastening hole 348 First fixture 350 Left bus bar 352 Third extended body 354 Fourth extended body 356 Second fastening hole 358 Second fixture 360 Right mounting body 370 Left mounting body 380 Central mounting body X First direction Y Second direction Z Third direction

Claims

1. A voltage detection unit that detects the voltage of at least one battery cell; a bus bar, at least a portion of which electrically connects the at least one battery cell to an external device; a first mounting body to which the bus bar is attached; A second mounting body to which the voltage detection unit is attached; Equipped with The first mounting body and the second mounting body are connected to each other, The first mounting body has heat resistance, The heat resistance of the second mounting body is lower than the heat resistance of the first mounting body, the first mounting body includes at least one of polybutylene terephthalate and modified polyphenylene ether, The second mounting body comprises polypropylene.

2. The voltage sensing device of claim 1 , wherein the first mounting body comprises a fabric material.

3. The voltage detection device according to claim 1 , wherein the voltage detection unit is electrically connected to a lead portion that is folded back between different battery cells.

4. A voltage detection device according to any one of claims 1 to 3, the at least one battery cell; A battery module comprising:

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