JP7522009B2 - Battery Module - Google Patents

Description

This disclosure relates to a battery module.

For example, JP 2017-4803 A discloses a battery pack that includes a battery stack formed by stacking multiple battery cells, a busbar module provided on the upper surface of the battery stack, and a thermistor that detects the temperature of the battery cells.

JP 2017-4803 A

In a battery pack such as that described in JP 2017-4803 A, a dedicated mechanism is required to detect the gas (smoke) generated from the secondary battery.

The objective of this disclosure is to provide a battery module that makes it possible to omit a dedicated smoke detection mechanism.

A battery module according to one aspect of the present disclosure includes a plurality of secondary batteries arranged in one direction, a smoke exhaust duct provided on the plurality of secondary batteries for discharging gas generated from the secondary batteries, a thermistor provided on the plurality of secondary batteries at a position spaced apart from the smoke exhaust duct and capable of detecting the temperature of the secondary batteries, and a busbar module provided on the plurality of secondary batteries, the secondary batteries having a pair of external terminals, the busbar module having a plurality of busbars electrically connecting the external terminals adjacent to each other in the one direction, and a busbar case holding the plurality of busbars, the busbar case having an induction portion for guiding the gas flowing out from the smoke exhaust duct to the thermistor.

This disclosure makes it possible to provide a battery module that does not require a dedicated smoke detection mechanism.

1 is a perspective view showing a schematic configuration of a battery module according to an embodiment of the present disclosure. FIG. 2 is a cross-sectional view of a battery module. FIG. 2 is an exploded perspective view of a portion of the battery module. FIG. 2 is a perspective view of a secondary battery and a resin frame. 13 is a perspective view showing a relationship between a locking portion of the resin frame and a locked portion of the busbar case. FIG. FIG. 4 is a perspective view showing the relationship between a thermistor and an induction portion. FIG. 4 is a diagram showing the relationship between the smoke exhaust path and the induction section. FIG. 2 is a perspective view of a bus bar module and an FPC. FIG. 2 is a perspective view of a bus bar module and an FPC cover. FIG. 4 is a cross-sectional view showing a state in which a wire has entered the battery module.

Embodiments of the present disclosure will be described with reference to the drawings. Note that in the drawings referred to below, identical or equivalent components are given the same numbers.

Figure 1 is a cross-sectional view that shows a schematic configuration of a battery module according to one embodiment of the present disclosure. This battery module 1 is mounted, for example, on a vehicle.

As shown in Figures 1 to 4, the battery module 1 includes a plurality of secondary batteries 100, a plurality of resin frames 200, a thermistor 300, a busbar module 400, an FPC 510, an FPC cover 520, an insulating cover 530, a damper member 610, a pressing member 620, a lower case 710, and an upper case 720.

The multiple secondary batteries 100 are arranged in one direction (a direction perpendicular to the paper surface in FIG. 2). An example of the secondary battery 100 is a lithium ion battery. Each secondary battery 100 has a case 110 and a pair of external terminals 120.

The case 110 is formed in a rectangular shape. As shown in FIG. 4, a safety valve V is provided in the center of the top surface of the case 110.

A pair of external terminals 120 protrude upward from the top surface of the case 110. One of the pair of external terminals 120 is a positive terminal, and the other is a negative terminal. The positive terminal is provided on one side of the safety valve V in the width direction (a direction perpendicular to both the one direction and the up-down direction). The negative terminal is provided on the other side of the safety valve V in the width direction.

The resin frame 200 is arranged adjacent to the secondary battery 100 in one direction. Each resin frame 200 has a partition portion 210, a duct element 220, and a tab 230.

The partition 210 is made of an insulating material (resin). The partition 210 separates the secondary batteries 100 adjacent to each other in one direction.

As shown in FIG. 4, the duct element 220 is connected to the upper part of the partition 210. The duct element 220 has a shape that covers the safety valve V of each secondary battery 100. Each duct element 220 is connected to the duct element 220 adjacent in one direction. The multiple duct elements 220 are connected to each other to form a smoke exhaust duct 220A. The smoke exhaust duct 220A is provided on the multiple secondary batteries 100 and forms a smoke exhaust path C (see FIG. 4 and FIG. 7) for exhausting gas generated from the secondary battery 100. Note that one resin frame 200 is omitted in FIG. 4 for the sake of explanation.

The tabs 230 are provided at both ends of the partition 210 in the width direction. As shown in Figures 4 and 5, the tabs 230 have a protruding piece 232 and a locking portion 234.

The protruding piece 232 has a shape that protrudes upward from the partition section 210. The protruding piece 232 is formed in a flat plate shape that is perpendicular to the width direction.

The locking portion 234 has a shape that protrudes outward in the width direction from the protruding piece 232. The locking portion 234 has a shape that protrudes more from the protruding piece 232 as it extends downward.

The thermistor 300 is capable of detecting the temperature of the secondary battery 100. The thermistor 300 is provided on the multiple secondary batteries 100 and at a position spaced apart from the smoke exhaust duct 220A. The thermistor 300 is provided so as to be in contact with the upper surface of the case 110.

The busbar module 400 is arranged on multiple secondary batteries 100. The busbar module 400 has multiple busbars 410 and a busbar case 420.

Each bus bar 410 electrically connects adjacent external terminals in one direction. In this embodiment, each bus bar 410 electrically connects the positive terminal of one secondary battery to the negative terminal of the secondary battery adjacent to the one secondary battery. In other words, the multiple secondary batteries 100 are connected in series by each bus bar 410.

The busbar case 420 holds each busbar 410. The busbar case 420 is made of resin. The busbar case 420 has a plurality of latched portions 422, a thermistor holding portion 424, an induction portion 426, and a plurality of pillar portions 428.

Each of the locked portions 422 is provided on the outside of each of the bus bars 410 in the width direction. The locked portions 422 have a shape that surrounds the tab 230. The locked portions 422 are capable of engaging with the locking portions 234 of the tab 230. As shown in FIG. 5, the locked portions 422 are provided with slits S. When the locked portions 422 are connected to the tab 230 from above, they extend outward in the width direction and overcome the locking portions 234.

The thermistor holding portion 424 holds the thermistor 300. As shown in Figures 6 and 7, the thermistor holding portion 424 is provided at a position spaced apart from the smoke exhaust duct 220A (smoke exhaust path C) in the width direction. The thermistor holding portion 424 holds the thermistor 300 so that the bottom surface of the thermistor 300 contacts the top surface of the case 110 of the secondary battery 100.

The induction section 426 induces the gas G (see FIG. 7) flowing out from the smoke exhaust duct 220A to the thermistor 300. As shown in FIG. 6, the induction section 426 has a pair of induction pieces 426a. The pair of induction pieces 426a are spaced apart from each other in one direction. Each induction piece 426a has a shape that extends in a direction parallel to the width direction. Each induction piece 426a is formed in a flat plate shape. The distance between the pair of induction pieces 426a is set to be larger than the dimension of the thermistor 300 in one direction.

Each pillar portion 428 is in contact with the upper surface of the resin frame 200. The pillar portion 428 has a shape that extends upward from the upper surface of the resin frame 200. The upper surface of the pillar portion 428 is formed flat. The pillar portion 428 is provided between the locked portion 422 and the thermistor holding portion 424. The multiple pillar portions 428 are arranged so as to be aligned at equal intervals in one direction.

The FPC 510 electrically connects each bus bar 410. The FPC 510 has a shape that extends in one direction. The FPC 510 is disposed on multiple secondary batteries 100.

The FPC cover 520 has a shape that covers the FPC 510. As shown in Figures 3, 5, and 9, the FPC cover 520 has a shielding portion 522.

The shielding portion 522 shields the FPC 510 from the welded portion between the bus bar 410 and the external terminal 120. Specifically, the shielding portion 522 prevents spatter generated when welding the bus bar 410 to the external terminal 120 from scattering toward the FPC 510.

The insulating cover 530 is provided on the FPC cover 520. The insulating cover 530 sandwiches the FPC cover 520 together with the busbar case 420. The insulating cover 530 has a recess 532. As shown in FIG. 3, the recess 532 has a shape that extends in one direction. The lower surface of the recess 532 contacts the upper surface of the column portion 428.

The damper member 610 is made of an elastically deformable material. As shown in FIG. 2, the damper member 610 is disposed in the recess 532.

The pressing member 620 is a member that presses the multiple secondary batteries 100 downward via the damper member 610, the insulating cover 530, and the busbar case 420. The pressing member 620 is formed in a plate shape. The pressing member 620 is made of, for example, metal.

As shown in FIG. 10, the pressing member 620 has a prevention rib 622 that prevents the wire 10 from entering from near the fastening portion of the wire harness. The prevention rib 622 receives the tip of the wire 10, thereby preventing the wire 10 from reaching the live part 20.

The lower case 710 houses multiple secondary batteries 100. In this embodiment, as shown in FIG. 2, the lower case 710 houses a first battery stack 151 and a second battery stack 152 arranged adjacent to the first battery stack 151 in the width direction. Each battery stack includes multiple secondary batteries 100 and multiple resin frames 200. In this embodiment, a damper member 612 is provided between the lower case 710 and each battery stack.

The upper case 720 is fixed to the lower case 710. As shown in FIG. 2, the upper case 720 has a shape that covers each battery stack together. The upper case 720 is disposed above the pressing member 620.

As described above, the battery module 1 of this embodiment has an induction section 426 that induces the gas G flowing out of the smoke exhaust duct 220A to the thermistor 300, so that the thermistor 300 that detects the temperature of the secondary battery 100 can detect the generation of smoke exhaust. Therefore, a dedicated mechanism for detecting smoke exhaust is not required.

In addition, since the resin frame 200 has a tab 230 and the busbar case 420 has an engaging portion 422, it is easy to position the secondary battery 100 and the busbar 410.

In addition, since the engaged portion 422 has a slit S, it is possible to remove the busbar case 420 from the resin frame 200 without using a special tool.

In addition, the pressing member 620 presses the multiple secondary batteries 100 downward (towards the lower case 710) via the damper member 610, etc., thereby preventing each secondary battery 100 from floating up from the lower case 710.

It will be understood by those skilled in the art that the exemplary embodiments described above are specific examples of the following aspects:

The battery module in the above embodiment includes a plurality of secondary batteries arranged in one direction, a smoke exhaust duct provided on the plurality of secondary batteries for discharging gas generated from the secondary batteries, a thermistor provided on the plurality of secondary batteries and at a position spaced apart from the smoke exhaust duct and capable of detecting the temperature of the secondary batteries, and a busbar module provided on the plurality of secondary batteries, the secondary batteries having a pair of external terminals, the busbar module having a plurality of busbars electrically connecting the external terminals adjacent to each other in the one direction, and a busbar case holding the plurality of busbars, the busbar case having an induction portion for guiding the gas flowing out from the smoke exhaust duct to the thermistor.

It is also preferable that the battery module further includes a partition section made of an insulating material that separates the secondary batteries adjacent to each other in the one direction, and that the smoke exhaust duct is made of a plurality of duct elements connected to each other in the one direction, and each duct element is connected to an upper portion of the partition section.

It should be noted that the embodiments disclosed herein are illustrative in all respects and should not be considered limiting. The scope of the present invention is indicated by the claims rather than the description of the embodiments above, and further includes all modifications within the meaning and scope of the claims.

1 Battery module, 100 Secondary battery, 110 Case, 120 External terminal, 200 Resin frame, 210 Partition, 220 Duct element, 220A Smoke exhaust duct, 230 Tab, 232 Projecting piece, 234 Locking part, 300 Thermistor, 400 Busbar module, 410 Busbar, 420 Busbar case, 422 Locking part, 424 Thermistor holding part, 426 Induction part, 426a Induction piece, 428 Pillar part, 510 FPC, 520 FPC cover, 522 Shielding part, 530 Insulating cover, 532 Recess, 610 Damper member, 620 Pressing member, 710 Lower case, 720 Upper case, C Smoke exhaust path, S Slit, V Safety valve.

Claims (2)

A plurality of secondary batteries arranged in one direction;
a smoke exhaust duct provided on the plurality of secondary batteries for exhausting gas generated from the secondary batteries;
a thermistor provided on the plurality of secondary batteries and spaced from the smoke exhaust duct, the thermistor being capable of detecting a temperature of the secondary batteries;
a busbar module disposed on the plurality of secondary batteries,
The secondary battery has a pair of external terminals,
The busbar module includes:
a plurality of bus bars electrically connecting the external terminals adjacent to each other in the one direction;
a bus bar case for holding the plurality of bus bars,
The busbar case has an induction portion that induces the gas flowing out from the smoke exhaust duct to the thermistor. a partition portion made of an insulating material and separating the secondary batteries adjacent to each other in the one direction;
The smoke exhaust duct is composed of a plurality of duct elements connected to each other in the one direction,
The battery module according to claim 1 , wherein each duct element is connected to an upper portion of the partition.

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