JP2022103535A - Cooling structure for battery pack - Google Patents

Abstract

To improve the air blow circulation efficiency inside a sealed battery pack, and thereby, to simplify the structure and provide uniform temperature distribution and a cooling effect.SOLUTION: In a battery pack 1, a swollen part 12 is formed above a rear part in a vehicle length direction FR of a battery case (upper and lower cases 10 and 20). On an upper surface 11 extending forward in the vehicle length direction from the rear part, a ridge part 13 protruded upward and extending in the vehicle length direction is formed. An airflow passage Fa1 communicated with the inside of the swollen part is formed between an inner surface of the ridge part 13 and an upper surface of battery modules 31 and 32. In the swollen part, a blower fan 5 arranged above in a vehicle height direction H for the battery modules is provided, and blow ducts 41 and 42 for sending air sent out from the blower fan while pressurizing the air into air outlets 427 and 428 located at an intermediate part in the vehicle length direction and the vehicle width direction in the plurality of battery modules are provided. The air Fa, Fb sent out from the air outlets circulates in the swollen part through a gap between the plurality of battery modules and through the airflow passages Fa1 and Fb1.SELECTED DRAWING: Figure 4

Description

The present invention relates to a cooling structure for a battery pack mounted on a vehicle.

A battery pack mounted on a vehicle, for example, a battery pack of an electric vehicle, is a flattened module composed of a plurality of secondary batteries in order to increase the capacity while securing the vehicle interior space and the luggage compartment space. It is arranged inside the case and placed on the floor of the vehicle body or under the floor. Since the secondary battery generates heat during charging and discharging, the battery pack has a cooling structure.

The cooling structure of the battery pack includes an open type that introduces outside air and a closed type that uses a heat pump, but the former has a problem against the intrusion of rainwater and dust, and the latter has a compressor and a radiator outside the battery pack. It is necessary (see Patent Document 1), the cooling system cannot be completed by the battery pack alone, the system becomes complicated, and there are problems such as condensed water generated by the internal evaporator.

Japanese Unexamined Patent Publication No. 2011-11632

Therefore, a method of providing a blower fan inside the sealed battery pack to make the temperature distribution inside the battery pack uniform and to improve the efficiency of heat dissipation from the battery case as a heat dissipation member to the outside is being reexamined.

The present invention has been made in view of such circumstances, and an object of the present invention is to improve the air circulation efficiency inside the battery pack, simplify the structure, make the temperature distribution inside the battery pack uniform, and perform the desired cooling. To achieve the effect.

In order to solve the above problems, the present invention
A battery pack cooling structure with multiple battery modules inside a substantially sealed battery case.
The battery case is formed of a heat conductive material as a heat dissipation member.
The plurality of battery modules are fixedly arranged in the battery case with a gap between them.
An upwardly bulging portion is formed at the rear portion of the battery case in the vehicle length direction, and a ridge portion extending upward and extending in the vehicle length direction is formed on the upper surface of the rear portion extending forward in the vehicle length direction. Is formed, and an air flow path communicating with the inside of the bulging portion is formed between the inner surface of the ridge portion and the upper surface of the battery module.
A blower fan arranged above the battery module in the vehicle height direction is provided inside the bulge portion, and air sent from the blower fan is directed in the vehicle length direction and the vehicle width direction of the plurality of battery modules. It is equipped with a ventilation duct for pumping to at least one outlet located in the middle of the
The air sent out from the outlet is provided in the cooling structure of the battery pack, which is configured to be circulated into the bulge through the gaps of the plurality of battery modules and the air flow path. be.

According to the above configuration, the cooling structure of the battery pack according to the present invention is such that the battery module is cooled by the air blown to the middle portion of the battery module, the temperature rises due to heat exchange with the battery module, and the air moved upward is ridged. Since it is circulated to the blower fan in the bulge through the air flow path formed between the inner surface of the portion and the upper surface of the battery module, it is circulated to the outside by heat exchange with the upper surface of the battery case whose surface area is increased by the ridge. The heat dissipation is promoted, and the ridges (air flow paths) extending toward the blower fan improve the air circulation efficiency inside the battery pack, making the temperature distribution of the battery module uniform while avoiding the complication of the structure. A cooling effect can be obtained.

It is a perspective view which shows the appearance of a battery pack. It is a perspective view which shows the inside of a battery pack. It is a top view which shows the inside of a battery pack. FIG. 1 is a sectional view taken along the line AA of FIG. It is BB sectional view of FIG. It is an enlarged sectional view of the main part of FIG.

Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.

(Overview of battery pack)
As shown in FIG. 1, the battery pack 1 according to the embodiment of the present invention has an overall flat shape except for the rear bulging portion 12 on the premise that the battery pack 1 is mounted under the floor of the vehicle. In the following description, unless otherwise specified, "front and rear" means front and rear sides in the vehicle length direction FR, and "left and right" means left and right sides in the vehicle width direction W toward the front F in the vehicle length direction. Means, "up and down" corresponds to each of the upper and lower sides in the vehicle height direction H.

As shown in FIGS. 1 to 5, the battery pack 1 includes a plurality of battery modules 31 and 32 inside a battery case including an upper case 10 and a lower case 20. Each of the battery modules 31 and 32 is modularized by holding a plurality of secondary battery cells (such as a lithium ion secondary battery) connected in series to each other in a stacked state in a box-shaped or frame-shaped inner case. It was done.

The upper case 10 and the lower case 20 are formed in a shell shape or a tray shape by a press-molded product of a metal having good thermal conductivity such as steel, stainless steel, and an aluminum alloy, and themselves function as a heat dissipation member to the outside. have.

As shown in FIG. 1, the upper case 10 constituting the upper portion of the battery pack 1 has a ridge extending in the vehicle length direction FR in the center of the vehicle width direction W on the upper surface 11 from the front portion to the rear portion in the vehicle length direction. A portion 13 is formed, and three small ridge portions 15 (bead portions 151, 152, 153) extending in parallel with the vehicle length direction FR are formed on each of the left and right sides thereof. Further, the meeting portion 14 with the ridge portion 13 on the inclined surface 122 on the front side of the bulging portion 12 is formed in a funnel shape that rises and expands toward the bulging portion 12.

The ridges 13 and the small ridges 15 have a reinforcing structure (reinforcing bead portion) for improving the surface rigidity of the upper surface 11 of the upper case 10, and at the same time, circulate inside the upper case 10 as described later. It is also a component of the cooling structure that forms the air flow path (return flow path).

The ridge portion 13 is formed so that the protrusion height of the rear portion is larger than that of the front portion of the FR in the vehicle length direction, or the protrusion height of the ridge portion 13 increases toward the bulging portion 12. It is preferable that it is formed in such a manner.

Although the upper surface 11 of the upper case 10 has the above-mentioned ridges 13 and small ridges 15, it is formed substantially flat as a whole, whereas the rear portion of the upper case 10 is under the rear seat of the vehicle. A bulging portion 12 that bulges upward is formed so as to be accommodated in the lower space of the kick-up portion. The internal space expanded upward by the bulging portion 12 is an installation space for the blower duct 4 and the blower fan 5 constituting the cooling system, and at the same time, dissipates heat separated from the battery modules 31 and 32 as described later. It is also a space.

In the battery pack 1, the battery modules 31 and 32 and their control devices are housed in the lower case 20, and components such as the blower duct 4 and the blower fan 5 constituting the cooling system are arranged to complete the necessary wiring. , The flange portion 20f around the lower case 20 and the flange portion 10f of the upper case 10 are joined and integrated with bolts or the like via a sealing material 20c so as to ensure waterproofness and airtightness. Has been done.

A support frame 25, which is a support frame for the battery pack 1, is fixed to the lower surface of the lower case 20. As shown in FIG. 4, the support frame 25 includes a pair of left and right side frames 250 and a plurality of cross frames 251,252,253,254,255 extending and rigidly coupled in the vehicle width direction W between them. It is configured like a ladder by.

The battery pack 1 is provided with four mounting brackets 21, 22, 23, 24 on each of the left and right sides as mounting portions to the vehicle body. Of these, the mounting brackets 22, 23, 24 excluding the front portion are the upper bracket joined to the flange portion 10f of the upper case 10 of the battery pack 1 and the lower bracket joined to the flange portion 20f of the lower case 20. It is configured. The battery pack 1 is fixed to the vehicle body by fastening bolts inserted from below into the bolt holes of the mounting brackets 21, 22, 23, 24 to the weld nuts of the vehicle body side mounting portion.

The battery pack 1 is provided with a high-voltage connector 33 for power input / output to a vehicle drive motor on the front end surface of the lower case 20, and for charging on the rear surface of the upper case 10 (bulging portion 12). A high voltage connector 36 is disposed. Further, a service plug 34 for cutting off the power of the battery modules 31 and 32 is arranged on the upper surface 11 of the upper case 10 during inspection or in an emergency, and the upper surface 121 of the bulging portion 12 of the upper case 10 is provided with a service plug 34. A control connector 35 is arranged.

(Arrangement of battery modules)
Inside the battery pack 1, as shown in FIGS. 2 and 3, four battery modules 32 (32a, 32j) at the foremost portion match their longitudinal directions with the vehicle length direction FR and are interspersed with each other. It is arranged side by side with gaps 320 and 322, and in the middle part of the battery pack 1 behind them, four battery modules 32 (32b) in the same arrangement are arranged in the longitudinal direction of the vehicle length. They are arranged side by side in line with the direction FR.

In the illustrated example, the module 32j, which is the second module from the right in the front part, is a junction box provided with a relay circuit for supplying / cutting power to the high voltage connector 33. For example, this function is expanded. It may be integrated into the junction box 38 of the unit 12 to form a battery module, and will be described as the battery module 32 for convenience.

At the rear of the inside of the battery pack 1, as shown by the broken line in FIG. 3, there is a gap 330 with respect to the battery module 32b in the intermediate portion, and four battery modules 31 (31c, 31d) are respectively. The longitudinal direction coincides with the vehicle width direction W, and they are juxtaposed with gaps 310 and 312 between them. Of these, the two battery modules 31d on the left side are half-sized modules having a smaller number of secondary battery cells and a shorter length in the longitudinal direction than the other battery modules.

As shown in FIGS. 4 and 5, each battery module 31, 32 is fixed to a reinforcing frame 26, 27, 28 arranged at the inner bottom portion of the lower case 20.

That is, as shown in FIG. 4, the front and middle battery modules 32 extend in the vehicle width direction W arranged at three locations separated from the front to the middle of the inner bottom of the lower case 20. Bolted to the reinforcing frame 26 at both front and rear ends in the longitudinal direction, the four rear battery modules 31 are spaced apart from both sides and the middle of the rear inner bottom of the lower case 20, as shown in FIG. It is fixed to the arranged reinforcing frames 27, 28 extending in the vehicle length direction FR with bolts at both left and right ends in the longitudinal direction.

In the following description, the four battery modules 31 (31c, 31d) at the rear of the battery pack 1 are collectively referred to as the first battery module group 31, and the eight battery modules at the front and middle of the battery pack 1 described above. 32 (32a, 32b) may be collectively referred to as a second battery module group 32.

(Battery module cooling system)
As shown in FIGS. 2 to 5, on the upper side of the four battery modules 31 arranged at the rear of the battery pack 1, a support plate for disposing the air duct 4 and the air fan 5 constituting the cooling system is arranged. 17 is provided.

The support plates 17 are fixed to the reinforcing frame 27 via the legs 18 on both sides in the vehicle width direction. The leg portion 18 is formed of an inverted U-shaped member in which both ends of a frame member extending in the vehicle width direction W along the lower surface of the support plate 17 are bent downward, and each lower end portion (flange portion) is formed. It is fixed to the reinforcing frame 27 with bolts.

The support plate 17 extends at a height substantially equal to the upper surface 11 of the upper case 10 with a space between the support plate 17 and the upper surface of the battery module 31, and provides an internal space of the bulging portion 12 of the upper case 10. , Except for the peripheral portion, it is provided so as to partially partition from the lower battery module 31 side, and has a space between the side surface and the rear surface of the bulging portion 12.

A blower fan 5 is arranged at a substantially central portion of the support plate 17 in the vehicle width direction W. Further, a control device 37 for performing battery charge / discharge management, cell balance control, and the like is arranged on the right side of the blower fan 5, and a junction box 38 for the high voltage connector 36 is arranged on the left side of the blower fan 5. A ventilation duct 4 (second branch duct portion 42) is arranged along the front edge portion of the support plate 17 on the front side thereof.

A centrifugal fan (sirocco fan or turbo fan) can be preferably used as the blower fan 5, and the support plate 17 is provided so that the rotation axis direction coincides with the vehicle height direction H and the intake port 50 is located on the upper part of the fan case. It is fixed with a bolt on the top. In the illustrated example, the sirocco fan in which the motor is arranged inside the fan hub is used so that the motor housing does not protrude downward and a sufficient air flow path is secured above the intake port 50.

The blow duct 4 has an opening of a support plate 17 from a base 40 extending forward from the discharge port 54 of the blow fan 5 and a communication portion 410 at the bottom of a substantially intermediate portion of the base 40, as shown in FIGS. 5 and 6. It includes a first branch duct portion 41 that penetrates 70 and extends downward, and a second branch duct portion 42 that is connected to the front end portion of the base 40, as shown in FIGS. 2 and 3.

(Ventilation duct; 1st branch duct part)
As shown in FIGS. 3 and 5, the first branch duct portion 41 is an intermediate portion (310, 312) between the vehicle length direction FR and the vehicle width direction W of the four battery modules 31c and 31d of the first battery module group 31. ), It communicates with a pair of first outlets 417 and 418 opened in both the left and right directions toward the gaps 310 and 310 of the respective battery modules 31c and 31d.

As shown in FIG. 6, the first branch duct portion 41 is composed of a member separate from the base portion 40 and is not directly connected to the base portion 40. That is, the first branch duct portion 41 is provided with a thick portion 41e at the lower end portion 41b, and the lower end portion 41b (thick portion 41e) is fitted in the gap 310 of the battery modules 31 and 31. The upper end portion 41a facing the communication portion 410 is held between the support plate 17 and the reinforcing frame 28 by abutting the lower surface around the opening 70 of the support plate 17 via the elastic sealing member. The thick portion 41e may be a rib projecting from the lower end portion 41b of the first branch duct portion 41, or a spacer formed of a member different from the lower end portion 41b.

In such mounting of the first branch duct portion 41, after the mounting and wiring of the four battery modules 31c and 31d on the lower side of the support plate 17 are completed, the first branch duct portion 41 is placed in the gap between the battery modules 31c and 31d. The support plate 17 is attached to the upper side of the battery modules 31 and 31 in a temporarily fixed state by holding the lower end portions 41b (thick portion 41e) on the side surfaces of the battery modules 31 and 31 and the upper surface of the reinforcing frame 28. The support plate 17 and the reinforcing frame 28 are restrained from both upper and lower sides via an elastic sealing member.

After that, the base 40 of the blow duct 4 is fixed to the upper surface of the support plate 17 together with the blow fan 5, and the lower surface around the communication portion 410 hits the upper surface around the opening 70 of the support plate 17 via the elastic sealing member. By contacting each other, the air flow path of the first branch duct 41 from the base 40 to the first outlets 417 and 418 via the communication portion 410 is formed.

(Ventilation duct; 2nd branch duct)
As shown in FIGS. 2 and 3, the second branch duct portion 42 is an upstream portion (first section) extending from the front end portion of the base portion 40 to both sides in the vehicle width direction W along the front edge portion of the support plate 17. 421, upstream portion (second section) 422 leading to the first bent portion 423 adjacent to the side portion of the battery case 1, downstream portion (first section) 424 extending forward and downward from the first bent portion 423 in the vehicle length direction. Includes a downstream portion (second section) 426 that bends at a second bent portion 425 in front of the vehicle and extends toward the center of the vehicle width direction W.

The downstream portion (second section) 426 is a battery module from the middle portion (320, 322) of the vehicle length direction FR and the vehicle width direction W of each of the four left and right battery modules 32a and 32b of the second battery module group 32. It communicates with each pair of second outlets 427 and 428 that are opened forward and backward toward the gap 320 of 32a and 32b.

The upstream portions 421 and 422 of the second branch duct portion 42 are fixed to the support plate 17 by fastening members or the like at the front and lower portions of the left and right second sections 422 and a plurality of mounting portions. The downstream portions 424 and 426 of the second branch duct portion 42 are fixed to the inner bottom portion of the lower case 20 by fastening members or the like at the side portions of the first section 424 and a plurality of mounting portions.

(Air circulation and cooling action inside the battery pack)
In the cooling system configured as described above, the air in the bulging portion 12 is sucked from the intake port 50 by operating the blower fan 5.
(I) First cooling air Fc, Fd (FIG. 3, Fd) that is pumped through the first branch duct portion 41 extending downward from the base 40 of the blow duct 4 and blown out from the first outlets 417 and 418 to the left and right sides. 5 and 6), and
(Ii) The air is pumped from the base 40 of the air duct 4 through the upstream portions 421 and 422 of the second branch duct portion 42 and the downstream portions 424 and 426, and is blown out from the second outlets 427 and 428 on the left and right sides to the front and rear sides. The second cooling air Fa, Fb (FIGS. 2 to 4) is generated.

As shown in FIGS. 3 and 5, the first cooling air Fc and Fd have the vehicle widths of the respective battery modules 31c and 31d from the intermediate portion of the four battery modules 31c and 31d of the first battery module group 31. It flows to the left and right sides along the gaps 310 and 310 in the direction W, and in this process, the battery modules 31c and 31d are cooled by heat exchange with the battery modules 31c and 31d.

The air heated by heat exchange with the battery modules 31c and 31d rises from the gaps on both the left and right sides in the battery pack 1 as shown by arrows Fc1 and Fd1 in FIG. 5, and sucks the blower fan 5. The lower case is collected in the upper bulging portion 12 of the support plate 17, which is slightly negatively pressured by the air, and flows from the side wall portion of the lower case 20 and the bulging portion 12 along the ceiling portion of the bulging portion 12. While radiating heat by exchanging heat with the 20 and the upper case 10, the air is sucked into the intake port 50 of the blower fan 5 as indicated by the arrows Fc2 and Fd2.

As shown in FIGS. 2 to 4, the second cooling air Fa and Fb are from the intermediate portions of the four left and right battery modules 32a and 32b of the second battery module group 32, respectively, of the battery modules 32a and 32b. It flows to the front and rear sides along the gaps 320 and 320 of the FR in the vehicle length direction, and in this process, the battery modules 32a and 32b are cooled by heat exchange with the battery modules 32a and 32b.

The air heated by heat exchange with each battery module 32a in the front portion rises at the front portion in the battery pack 1 as shown by the arrow Fa1 in FIG. 4, and rises in the ceiling portion (11, Along 13), while radiating heat by exchanging heat with the upper case 10, the air flows backward toward the bulging portion 12, which has a slightly negative pressure due to the suction of the blower fan 5. On the other hand, the air heated by the heat exchange with each battery module 32b in the intermediate portion also flows backward as shown by the arrows Fb1 and Fb2 while radiating heat by the heat exchange with the upper case 10, and the bulging portion 12 It is collected inside and sucked into the intake port 50 of the blower fan 5.

As described above, the inside (negative pressure area) of the bulging portion 12 of the battery pack 1 is separated from the lower side by the support plate 17 except for the peripheral portion, and the blower fan 5 (intake port 50) is arranged. By being installed, the pressure is slightly negative, and the air flow Fb2, Fc2, Fd2 toward the intake port 50 is generated along the ceiling portion.

On the other hand, the rear portion (first positive pressure area) of the battery pack 1 in which the first battery module group 31 is arranged and the cooling air Fc and Fd are blown out from the first outlets 417 and 418 of the air duct 4 to the left and right sides. , And the second battery module group 32 is arranged, and the front or middle portion (second) of the battery pack 1 in which the second cooling air Fa, Fb is blown out from the second outlets 427, 428 to the front and rear sides. Positive pressure area) is slightly positive pressure.

The temperature rise of the cooling air due to the pressure difference between the negative pressure area (12) and the first and second positive pressure areas (31, 32) as described above and the heat exchange between the first and second battery module groups 31 and 32. As a result, air circulation to the bulging portion 12, which is relatively the highest along the inner surface and the inner ceiling surface of the upper case 10, is promoted, and accordingly, the upper surface 11 of the upper case 10 and the upper surface of the bulging portion 12 are promoted. The heat exchange in 121 is promoted, the cooling effect of the first and second battery module groups 31 and 32 is obtained, and the temperature distribution of the first and second battery module groups 31 and 32 is made uniform.

Further, the vehicle length is formed between the upper surface of the second battery module group 32 and the inner ceiling surface of the upper case 10 by the ridges 13 and the small ridges 15 of the vehicle length direction FR formed on the upper surface 11 of the upper case 10. The cross-sectional area of the air flow path oriented in the direction FR is secured, and the formation of the air flow Fb1 flowing backward along the inner ceiling portion of the upper case 10 is promoted.

Further, the ridge portion 13 is formed in the substantially central portion of the vehicle width direction W, and the blower fan 5 is arranged in the substantially central portion of the bulging portion 12 in the vehicle width direction W, so that the most air is provided. There is also an advantage that air circulation from the ridge portion 13 which is the main air flow path having a large flow path cross section to the intake port 50 of the blower fan 5 is promoted.

Further, the structure is formed so that the protruding height of the ridge portion 13 increases toward the bulging portion 12, and the meeting portion 14 between the ridge portion 13 and the inclined surface 122 on the front side of the bulging portion 12 is a bulging portion. The funnel-shaped structure that rises and expands toward 12 further promotes air circulation as described above.

Further, the ridges 13 and small ridges 15 of the FR in the vehicle length direction formed on the upper surface 11 of the upper case 10 increase the heat exchange area on the upper surface 11 of the upper case 10, thereby increasing the heat exchange efficiency and heat dissipation efficiency. Improvement can also be expected.

Although the embodiments of the present invention have been described above, it is added that the present invention is not limited to the above embodiments, and various modifications and modifications can be made within the scope of the present invention.

1 Battery pack 4 Blower duct 5 Blower fan 10 Upper case 11 Top surface 12 Swelling part 13 Ridge part 14 Meeting part (funnel-shaped part)
15 Small ridge 17 Support plate 18 Leg 20 Lower case 26, 27, 28 Reinforcing frame 31, 31c, 31d Battery module (1st battery module group)
32, 32a, 32b Battery module (second battery module group)
40 Base 41 1st branch duct 42 2nd branch duct 50 Intake port 54 Discharge port 70 Opening 310, 312, 320, 322,330 Gap 410 Communication section 417,418 First outlet 421,422 Upstream section 424 426 Downstream 427,428 2nd outlet

Claims (7)

A battery pack cooling structure with multiple battery modules inside a substantially sealed battery case.
The battery case is formed of a heat conductive material as a heat dissipation member.
The plurality of battery modules are fixedly arranged in the battery case with a gap between them.
An upwardly bulging portion is formed at the rear portion of the battery case in the vehicle length direction, and a ridge portion extending upward and extending in the vehicle length direction is formed on the upper surface of the rear portion extending forward in the vehicle length direction. Is formed, and an air flow path communicating with the inside of the bulging portion is formed between the inner surface of the ridge portion and the upper surface of the battery module.
A blower fan arranged above the battery module in the vehicle height direction is provided inside the bulge portion, and air sent from the blower fan is directed in the vehicle length direction and the vehicle width direction of the plurality of battery modules. It is equipped with a ventilation duct for pumping to at least one outlet located in the middle of the
A battery pack cooling structure configured such that air delivered from the outlet is circulated into the bulge through the gaps of the plurality of battery modules and the air flow path. The plurality of battery modules are fixedly arranged at the lower part of the bulging portion of the battery case with a gap between them, and the first battery module group and the front of the first battery module group in the vehicle length direction. A second battery module group, which is fixedly arranged with a gap between them, is included, and the second battery module group is arranged side by side so that their longitudinal directions coincide with the vehicle length direction. The battery pack according to claim 1, wherein the at least one outlet includes at least one outlet arranged toward the vehicle length in a gap extending in the vehicle length direction of the second battery module group. Cooling structure. The battery pack cooling structure according to claim 1 or 2, wherein the ridge portion is formed in a substantially central portion in the vehicle width direction, and the blower fan is arranged substantially in the vehicle width direction of the bulging portion. .. The battery pack cooling structure according to any one of claims 1 to 3, wherein the ridge portion is formed so that the protrusion height increases toward the bulging portion. The battery pack cooling structure according to any one of claims 1 to 4, wherein the communication portion of the ridge portion with the bulging portion has an inclination that increases toward the bulging portion. The cooling structure for a battery pack according to claim 5, wherein the communication portion of the ridge portion with the bulging portion is expanded in a funnel shape. The upper surface extending forward in the vehicle length direction from the rear portion of the battery case is formed with a plurality of ridges extending upward in the vehicle height direction with respect to the upper surface of the plurality of battery modules and extending in the vehicle length direction. Item 6. The battery pack cooling structure according to any one of Items 1 to 6.

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