JP7655015B2 - Battery pack - Google Patents

Description

The present invention relates to a battery pack.

Patent Document 1 discloses a power supply device for a vehicle that includes a battery case that houses multiple batteries and an electronic component case that houses a relay that cuts off the battery current. The power supply device in Patent Document 1 is configured to transfer heat from the relay to the electronic component case by interposing an elastic heat conductive sheet between the relay and the electronic component case.

JP 2009-181737 A

However, in the power supply device described in Patent Document 1, the battery case that houses the battery and the electronic component case that houses the relay (semiconductor relay) are configured as separate entities, so there is room for improvement in terms of saving space.

The objective of the present invention is to obtain a battery pack that can save space while ensuring the cooling performance of the semiconductor relay.

The battery pack of claim 1 comprises a battery cell, an electronic board on which a semiconductor relay is mounted, and a case formed in a box shape capable of accommodating the battery cell, with the electronic board attached to a side surface and a fin member provided on a bottom surface continuous with the side surface, and a board cooling portion in contact with the semiconductor relay is provided on the side surface of the case, and a lattice-shaped groove is formed in the board cooling portion .

In the battery pack according to claim 1, the case is formed in a box shape capable of housing the battery cells. Fin members are provided on the bottom surface of the case. This allows heat generated in the battery cells to be dissipated by being transferred from the bottom surface of the case to the fin members. In addition, an electronic board is attached to the side surface of the case, and a semiconductor relay that cuts off the output of the battery is mounted on the electronic board. By attaching the electronic board to the side surface of the case in this way, space can be saved compared to a configuration that includes a separate case for housing electronic components.

Here, the side of the case is continuous with the bottom of the case. This allows heat generated in the semiconductor relay to be transferred from the side to the bottom of the case and dissipated through the fin members.

Furthermore , the surface area of the substrate cooling portion is increased by the lattice-like grooves formed in the substrate cooling portion, so that the heat dissipation effect of the substrate cooling portion can be improved.

According to a second aspect of the present invention, in the battery pack of the first aspect, a heat dissipating member is interposed between the semiconductor relay and the board cooling portion.

In the battery pack according to the second aspect of the present invention, heat generated in the semiconductor relay can be dissipated by the heat dissipation member while being transferred to the board cooling portion.

A battery pack according to a third aspect of the present invention is the battery pack according to the first or second aspect, wherein the electronic board is provided with a monitoring electronic component that monitors a state of the battery cells.

In the battery pack according to the third aspect, by mounting the semiconductor relay and the monitoring electronic components on a single electronic board, it is possible to achieve space saving compared to a configuration in which a separate electronic board is provided.

A battery pack according to a fourth aspect of the present invention is the battery pack according to any one of the first to third aspects, wherein the case is formed of a metal containing aluminum as a main component.

In the battery pack according to the fourth aspect, the case is made of a metal containing aluminum as a main component, which has high thermal conductivity, thereby improving the cooling performance.

As described above, the battery pack according to the present invention can save space while ensuring the cooling performance of the semiconductor relay.

FIG. 2 is an exploded perspective view of the battery pack according to the embodiment. 2 is a schematic cross-sectional view showing the battery pack of FIG. 1 as viewed from the right side. FIG. 1A and 1B are plan views of an electronic substrate according to an embodiment, in which FIG. 1A shows one side and FIG. 4 is an enlarged cross-sectional view of a main part taken along line 4-4 in FIG. 1; FIG. FIG. 2 is a perspective view of a case according to the embodiment. FIG. 3 is an enlarged cross-sectional view of a main part of FIG. 2 .

A battery pack 10 according to an embodiment will be described with reference to the drawings. In each drawing, for ease of explanation, the upward direction of the battery pack 10 is indicated by an arrow UP, the forward direction is indicated by an arrow FR, and the rightward direction is indicated by an arrow RH. The upward, forward, and rightward directions of the battery pack 10 are shown for ease of explanation, regardless of the orientation of the vehicle in which the battery pack 10 is mounted.

(Overall configuration of battery pack 10)
As shown in FIG. 1 , the battery pack 10 of this embodiment includes a case 12 , a battery stack 14 , a bus bar module 16 , a cover 18 , a cooling fan unit 20 , an electronic board 22 , and a connector module 24 .

As shown in Figs. 1 and 2, the case 12 is formed in a generally box-like shape with an open top. In addition, the case 12 in this embodiment is formed of a metal containing aluminum as a main component, as an example. For this reason, the case 12 is designed to have a higher thermal conductivity than resin, iron, and the like. The case 12 accommodates the battery stack 14 and the bus bar module 16. The case 12 is attached to the lower cover 11. Details of the case 12 will be described later.

As shown in FIG. 1, the battery stack 14 is a unit that stores power to drive the vehicle, and is composed of multiple battery cells 14A arranged in the front-rear direction, and is formed into a roughly rectangular parallelepiped shape overall.

The busbar module 16 is disposed above the battery stack 14, and the busbar module 16 electrically connects the multiple battery cells 14A that make up the battery stack 14.

The cover 18 is formed in a rectangular plate shape with its thickness direction being in the vertical direction, and the outer shape of the cover 18 is formed in a shape and size that covers the upper opening of the case 12. A number of insertion holes 18A are formed in the outer peripheral end of the cover 18, and the cover 18 is fastened to the case 12 by inserting bolts through these insertion holes. Fastening the cover 18 to the case 12 closes the upper opening of the case 12.

A cooling fan unit 20 is disposed in front of the case 12, and as shown in FIG. 4, the cooling fan unit 20 includes a fan 20A. The fan 20A is driven by being energized at a predetermined timing. When the fan 20A is driven, the air inside the cooling fan unit 20 is blown upward. Accordingly, the cooling air is configured to flow from the rear to the front along the underside of the case 12, as shown by the arrow X in the figure.

As shown in FIG. 1, an electronic board 22 is disposed on the right side of the case 12. As shown in FIG. 3(A), the electronic board 22 is formed in a substantially flat plate shape, and a plurality of semiconductor relays 30 are mounted on one side of the electronic board 22. The semiconductor relays 30 are disposed in parallel and configured to be able to cut off the current output from the battery stack 14 by the semiconductor relays 30 mounted in parallel. For example, the semiconductor relays 30 cut off the output of the battery stack 14 when the vehicle power is switched OFF.

As shown in FIG. 3B, a monitoring IC (Integrated Circuit) 32 is mounted on the other side of the electronic board 22 as a monitoring electronic component that monitors the state of the battery cell 14A. In other words, in this embodiment, the semiconductor relay 30 and the monitoring IC 32 are mounted on a single electronic board 22.

As shown in FIG. 1, the electronic board 22 is attached to the connector module 24. The connector module 24 is attached to the right side surface of the case 12 together with the electronic board 22. An exhaust pipe (not shown) and the like are connected to the connector module 24.

(Case 12)
Next, a detailed description will be given of the case 12 constituting the battery pack 10. As shown in Fig. 5, the case 12 is configured to include a bottom wall 40 constituting the bottom surface, and a side wall 42 constituting the side surface by extending upward from the periphery of the bottom wall 40. Therefore, the bottom wall 40 and the side wall 42 of the case 12 are continuous.

Here, a fin member 44 is provided on the bottom wall 40 of the case 12. The fin member 44 is composed of a number of ribs 44A protruding downward from the bottom wall 40, and each rib 44A extends with the longitudinal direction being the front-to-rear direction. Therefore, as shown in FIG. 4, it is configured so that cooling air can pass between adjacent ribs 44A.

As shown in FIG. 2, a heat dissipation putty 46 is provided as a heat dissipation member on the underside of the battery cells 14A that make up the battery stack 14. The heat dissipation putty 46 is interposed between the lower end of the battery cells 14A and the bottom wall 40 of the case 12, and is configured so that heat generated in the battery cells 14A is transferred to the bottom wall 40 via the heat dissipation putty 46.

As shown in FIG. 5, an opening 42A is formed in the right side wall 42 of the case 12. Four mounting holes 48 are formed around the periphery of the opening 42A, and bolts for fastening the connector module 24 are screwed into these mounting holes 48. The opening 42A is then closed by the connector module 24. In this way, the opening of the case 12 is closed by the cover 18 and the connector module 24, so that the interior of the case 12 is sealed in a waterproof and dustproof state.

Here, the opening 42A is provided with a substrate cooling section 50. The substrate cooling section 50 is formed in a shape corresponding to the electronic substrate 22. Specifically, the substrate cooling section 50 includes a central section 50A extending in the front-rear direction and having a front end connected to the front edge of the opening 42A, and an upper section 50B extending upward from the central section 50A and having a shorter length in the front-rear direction than the central section 50A. The front and rear ends of the upper section 50B extend upward and are connected to the upper edge of the opening 42A. The lower section 50C extends downward from the central section 50A, and this lower section 50C is connected to the lower edge of the opening 42A. The central section 50A, the upper section B, and the lower section 50C are integrally formed to constitute the substrate cooling section 50. Therefore, the substrate cooling section 50 is connected to the front edge and the lower edge of the opening 42A. In this embodiment, as an example, the lower section 50C is formed to a length of about half the lower edge of the opening 42A.

The substrate cooling section 50 is also formed with lattice-like grooves 52. The lattice-like grooves 52 are made up of grooves that extend in the front-rear direction and grooves that extend in the up-down direction, and the pitch of the grooves 52 is equal both vertically and front-to-back.

The semiconductor relay 30 of the electronic board 22 is in contact with the board cooling section 50. Specifically, as shown in FIG. 6, a heat dissipation putty 54 is interposed between the semiconductor relay 30 and the board cooling section 50 as a heat dissipation member, and the semiconductor relay 30 is in contact with the board cooling section 50 via this heat dissipation putty 54. Therefore, the heat generated from the semiconductor relay 30 is transferred to the board cooling section 50 via the heat dissipation putty 54, and is transferred from the board cooling section 50 to the bottom wall 40 of the case 12 as shown by the arrow Y in the figure.

(Action)
Next, the operation of this embodiment will be described.

As shown in FIG. 5, in the battery pack 10 according to this embodiment, a fin member 44 is provided on the bottom surface of the case 12, which is formed in a box shape capable of housing the battery cell 14A. This allows heat generated in the battery cell 14A to be transferred from the bottom surface of the case 12 to the fin member 44 and dissipated.

As shown in FIG. 6, an electronic board 22 is attached to the side of the case 12, and a semiconductor relay 30 that cuts off the output of the battery stack 14 is mounted on the electronic board 22. By attaching the electronic board 22 to the side of the case 12 in this way, a dedicated case for housing electronic components is no longer necessary, which allows for space savings.

Furthermore, in the battery pack 10 of this embodiment, the side wall 42 of the case 12 is continuous with the bottom wall 40 of the case 12. This allows heat generated in the semiconductor relay 30 to be transferred from the side wall 42 to the bottom wall 40 of the case 12 and dissipated from the fin member 44. As a result, it is possible to achieve space saving while ensuring the cooling performance of the semiconductor relay 30.

In addition, in the battery pack 10 of this embodiment, as shown in FIG. 5, the lattice-like grooves 52 formed in the substrate cooling section 50 increase the surface area of the substrate cooling section 50, thereby improving the heat dissipation effect of the substrate cooling section 50. In particular, by forming the substrate cooling section 50 into a plurality of blocks separated from each other by the lattice-like grooves 52 as in this embodiment, air can be circulated through the grooves 52 between the blocks, effectively preventing heat from building up in the substrate cooling section 50.

Furthermore, in this embodiment, the lower portion 50C of the substrate cooling section 50 is formed to a length approximately half the length of the lower edge of the opening 42A, so heat can be transferred more effectively from the substrate cooling section 50 to the bottom wall 40 compared to a configuration in which the lower portion 50C is short in both the front and rear directions.

Furthermore, in the battery pack 10 of this embodiment, as shown in FIG. 6, heat generated in the semiconductor relay 30 can be dissipated by the heat dissipation putty 54 while being transferred to the board cooling section 50. Similarly, heat generated in the battery cell 14A can be dissipated by the heat dissipation putty 46 while being transferred to the bottom wall 40 of the case 12, and can be dissipated from the fin member 44. That is, in the battery pack 10 of this embodiment, heat generated from the battery cell 14A (battery stack 14) and the semiconductor relay 30 can be effectively transferred by the fin member 44.

In particular, in this embodiment, the substrate cooling section 50 with which the heat dissipation putty 54 is in contact is formed unevenly by the lattice-shaped grooves 52, which can prevent the heat dissipation putty 54 from falling off.

In addition, in the battery pack 10 of this embodiment, by mounting the semiconductor relay 30 and the monitoring IC 32 on a single electronic board 22, it is possible to save space compared to a configuration in which a separate electronic board is provided. Furthermore, since the heat generated by the semiconductor relay 30 and the monitoring IC 32 can be transferred collectively to the board cooling section 50, there is no need to provide a separate cooling member.

Furthermore, in the battery pack 10 of this embodiment, the case 12 is formed from a metal whose main component is aluminum, which has high thermal conductivity. This allows for improved cooling performance compared to a case formed from a material such as resin or iron.

The battery pack 10 according to the embodiment has been described above, but it is of course possible to implement it in various forms without departing from the spirit of the present invention. For example, in the above embodiment, as shown in FIG. 6, a lattice-shaped groove 52 is formed in the substrate cooling section 50, but this is not limited thereto, and a configuration in which grooves of other shapes are formed may also be adopted.

In addition, in the above embodiment, as shown in FIG. 6, heat dissipation putty 46 is provided between the battery cell 14A and the bottom wall 40, but this is not limited to this. For example, another heat dissipation member may be provided between the battery cell 14A and the bottom wall 40 instead of the heat dissipation putty 46. Similarly, another heat dissipation member may be provided between the semiconductor relay 30 and the board cooling unit 50 instead of the heat dissipation putty 54.

REFERENCE SIGNS LIST 10 Battery pack 12 Case 14A Battery cell 22 Electronic board 30 Semiconductor relay 32 Monitoring IC (monitoring electronic component)
44 Fin member 50 Substrate cooling portion 52 Groove 54 Heat dissipation putty (heat dissipation member)

Claims (4)

A battery cell;
An electronic board on which a semiconductor relay is mounted;
a case formed in a box shape capable of housing the battery cells, with the electronic board attached to a side surface and a fin member provided on a bottom surface continuous with the side surface;
having
a substrate cooling portion in contact with the semiconductor relay is provided on a side surface of the case,
The battery pack, wherein the substrate cooling portion has a lattice-shaped groove formed therein . 2. The battery pack according to claim 1, further comprising a heat dissipation member interposed between the semiconductor relay and the board cooling portion . 3. The battery pack according to claim 1 , wherein the electronic board is provided with a monitoring electronic component for monitoring a state of the battery cells . 4. The battery pack according to claim 1, wherein the case is made of a metal containing aluminum as a main component .