JP2021061159A - Battery cooling structure for vehicle - Google Patents

Abstract

To provide a battery cooling structure for vehicles, advantageous in protecting electrical equipment from impact load in the case of a vehicle collision.SOLUTION: In a battery cooling structure for vehicles, a cooling air duct 16 is provided with two extension parts 40 extending along two battery module trains 36, respectively, between the two battery module trains 36, and electrical equipment is arranged between the two extensions 40. Even if impact load in the case of a collision is input to a battery case 12 to deform the battery case inward in the vehicle width direction and further to deform a battery module 34 inward in the vehicle width direction, the extensions 40 are located on the outside of the electrical equipment in the vehicle width direction, so that the impact load is received by the extensions 40 and it is advantageous in protecting the electrical equipment.SELECTED DRAWING: Figure 1

Description

The present invention relates to a vehicle battery cooling structure.

Vehicle power supplies that supply electric power to motors are used in electric vehicles such as electric vehicles and hybrid vehicles that use a motor as a drive source.
The vehicle power supply unit supplies high-voltage DC power to the motor, so it consists of an assembled battery configured by connecting a plurality of battery modules in which a plurality of battery cells are connected in series, and an electrical component electrically connected to the battery module. It is equipped with a device and a battery case for accommodating an assembled battery and electrical equipment.
Since the battery cell generates heat during charging or discharging, it is necessary to cool the battery module.
Therefore, a battery cooling structure is provided in which a plurality of battery modules are arranged in one direction to form a battery module row, and a cooling air duct extending along the battery module row is provided to supply cooling air from the cooling air duct to the battery module. It is provided (see Patent Documents 1 and 2).
Further, although not disclosed in Patent Documents 1 and 2, the electrical equipment is usually arranged adjacent to the battery module.

Japanese Unexamined Patent Publication No. 2006-324041 JP-A-2010-123298

In such a case, at the time of a vehicle collision, an impact load is input to the battery case and deformed inward, and this deformation may cause the battery module to displace and come into contact with or interfere with electrical equipment.
The present invention has been made focusing on a cooling air duct, and an object of the present invention is to provide a vehicle battery cooling structure that is advantageous for protecting electrical equipment from an impact load at the time of a vehicle collision.

In order to achieve the above object, the present invention includes a battery module array in which a plurality of battery modules are arranged in one direction, and a cooling passage extending along the battery module array to supply a cooling fluid to the battery module. A vehicle battery cooling structure including an electrical device electrically connected to the battery module, the battery module, the cooling passage, and a battery case accommodating the electrical device, wherein the battery module row is a battery cooling structure. At least two are provided at intervals in a direction orthogonal to the longitudinal direction thereof, and the cooling air duct extends between the two battery module rows along each of the two battery module rows. The electrical equipment is provided between the two extending portions.
According to the present invention, even if the impact load at the time of a vehicle collision is input to the battery case and deforms inward, and the battery module is further displaced inward, the extending portion of the cooling passage is located on the outside of the electrical equipment. Therefore, the extending portion receives the impact load, which is advantageous in protecting the electrical equipment.
Further, the present invention is characterized in that the electrical equipment includes at least one of a junction box for operating the battery module and a DC / DC converter for converting the output voltage of the battery module.
According to the above invention, it is advantageous in protecting the electrical equipment to which a high voltage is applied.
Further, the present invention is characterized in that at least a portion of the cooling air duct located on the electrical equipment side is made of an insulating material.
According to the above invention, the cooling passage portion made of an insulating material is advantageous in suppressing the electrical contact between the battery module and the electrical equipment to protect the electrical equipment.
Further, the present invention is characterized in that the cooling passage is made of metal.
According to the above invention, the impact load at the time of a vehicle collision is received by the metal cooling passage, and it is advantageous to prevent the battery module from approaching the electrical equipment side to protect the electrical equipment.
Further, in the present invention, the cooling fluid is cooling air, and the fan that sucks the cooling air that has cooled the plurality of battery modules and the cooling air discharged from the fan are cooled and guided to the cooling passage. The fan is provided with a cooler, and the fan is arranged between the two extending portions and at a position in the center or near the center of the battery case.
According to the above invention, since the pressure loss received by the cooling air flowing from each part in the battery case toward the fan can be made uniform, the cooling air can be smoothly circulated inside the battery case, which is advantageous in improving the cooling efficiency. It becomes.

According to the present invention, even if the impact load at the time of a vehicle collision is input to the battery case and deforms inward, and the battery module is further displaced inward, the extending portion of the cooling passage is located on the outside of the electrical equipment. Therefore, the extending portion receives the impact load, which is advantageous in protecting the electrical equipment.

It is a perspective view of the power supply device for a vehicle to which the battery cooling structure of the vehicle which concerns on embodiment is applied, and shows the state which the cover of the battery case is removed. It is a top view of the power supply device for a vehicle. FIG. 2 is a cross-sectional view taken along the line AA of FIG. FIG. 2 is a cross-sectional view taken along the line B1-B1 of FIG. 2 is a cross-sectional view taken along the line B2-B2 of FIG. FIG. 2 is a cross-sectional view taken along the line CC of FIG. FIG. 2 is a cross-sectional view taken along the line DD of FIG. FIG. 2 is a cross-sectional view taken along the line EE of FIG.

Hereinafter, embodiments of the present invention will be described with reference to the drawings.
The vehicle battery cooling structure of the present embodiment is applied to a vehicle power supply device.
The vehicle power supply device is mounted on an electric vehicle whose drive source is only a motor, a hybrid vehicle, or an electric vehicle whose drive source is a motor such as a plug-in hybrid vehicle.
In the drawings below, reference numeral UP indicates the upper part of the vehicle, reference numeral FR indicates the front of the vehicle, reference numeral IN indicates the inside in the vehicle width direction, and reference numeral OUT indicates the outside in the vehicle width direction.
As shown in FIGS. 1 and 2, the vehicle power supply device 10 is connected to the battery case 12, the assembled battery 14 housed in the battery case 12, the cooling air duct (cooling passage) 16, the fan 18, the cooler 20, and the connection. It includes a duct 22, a junction box 24, and a DC / DC converter 26.

The battery case 12 is made of metal and includes a tray 28 and a cover 30 (see FIG. 3).
The battery case 12, i.e., the tray 28 and the cover 30, has a height, a width that is greater than the height, and a length that is greater than the width.
The tray 28 includes a plate-shaped bottom wall 2802 having a rectangular shape in a plan view, a side wall 2804 standing up from the periphery of the bottom wall 2802, and an annular tray-side flange 2806 provided on the outer periphery of the upper end of the side wall 2804.
The tray 28 is arranged in the center of the vehicle width direction with the longitudinal direction aligned with the vehicle front-rear direction and the width direction aligned with the vehicle width direction, and is attached to the left and right side members via the mounting member 32. There is.
As shown in FIG. 3, the cover 30 has an upper wall 3002 facing the bottom wall 2802 of the tray 28, a side wall 3004 hung from the periphery of the upper wall 3002, and an annular shape provided on the outer periphery of the lower end of the side wall 3004. It is provided with a cover side flange 3006.
The tray 28 and the cover 30 are fastened with a plurality of bolts (not shown) in a state where the tray side flange 2806 and the cover side flange 3006 are overlapped with each other.

As shown in FIGS. 1 and 2, the assembled battery 14 is composed of a plurality of battery modules 34 electrically connected to each other, and in the present embodiment, the three battery modules 34 are one in a plan view. Two battery module rows 36 arranged in the direction are provided at intervals in a direction orthogonal to the longitudinal direction of the battery module rows 36.
In the present embodiment, the two battery module rows 36 are arranged at locations near both ends in the width direction of the tray 28 so that their longitudinal directions match the longitudinal direction of the tray 28.

As shown in FIG. 2, each battery module 34 is configured by arranging a plurality of battery cells 38 in the longitudinal direction of the tray 28, and the battery cells 38 are electrically connected to each other via a bus bar (not shown). There is.
The battery cell 38 is composed of a secondary battery, and various conventionally known secondary batteries such as a lithium ion secondary battery can be used as the secondary battery.
The battery cell 38 includes an electrode body and a case for accommodating the electrode body, and has a thin rectangular plate shape, and a terminal portion is provided on the upper end surface of the battery cell 38.

In the battery module 34, a plurality of battery cells 38 are arranged at equal intervals with the height direction facing up and down and the thickness direction facing the longitudinal direction of the tray 28, and are positioned and housed in a module housing (not shown). The module housing is attached to the bottom wall 2802 of the tray 28.
The module housing has a frame shape and is provided so as to cover the edges of a plurality of battery cells 38 housed therein.
Therefore, the end faces located at both ends in the height direction, the side surfaces located at both ends in the thickness direction, and the end faces located at both ends in the width direction of the plurality of battery cells 38 are opened inside the battery case 12, and each battery is opened. Cooling air (cooling fluid) is designed to flow through the gaps between the side surfaces of the battery cells 38 constituting the module 34.

The cooling air duct 16 supplies cooling air to the battery module 34.
As shown in FIGS. 1, 2, 4 to 8, the cooling air duct 16 extends linearly between the two battery module rows 36 along each of the two battery module rows 36. The extension portion 40 is provided.
Since the two battery module rows 36 are arranged at locations near both ends in the width direction of the tray 28 so that their longitudinal directions match the longitudinal direction of the tray 28, the trays are placed between the two extending portions 40. A space S1 extending in the longitudinal direction of the tray 28 is located at the center of the width direction of the tray 28.
A junction box 24, a fan 18, and a DC / DC converter 26 are arranged in the space S1, and coolers 20 are arranged at intervals from the DC / DC converter 26 on the extension of the space S1.
That is, the junction box 24, the fan 18, and the DC / DC converter 26 are arranged between the two extending portions 40 along the longitudinal direction of the tray 28, and more specifically, the junction box 24 is arranged at one end of the tray 28 in the longitudinal direction. The DC / DC converter 26 and the cooler 20 are arranged at the other end of the tray 28 in the longitudinal direction, and the fan 18 is arranged at the center or the vicinity of the center of the tray 28.

The junction box 24 and the DC / DC converter 26 function by being electrically connected to the battery module 34, and in the present embodiment, the electrical equipment includes the junction box 24 and the DC / DC converter 26. It is configured.
The junction box 24 is connected to the battery module 34 to make the battery module 34 function, and a high voltage is applied to the junction box 24.
The DC / DC converter 26 converts the output voltage from the battery module 34 and supplies the converted voltage to the inverter and accessories, and a high voltage is applied.
As shown in FIGS. 3 and 7, the DC / DC converter 26 includes a rectangular plate-shaped main body portion 2602 that generates heat during operation, and a plurality of heat radiating fins 2604 projecting downward are provided on the lower surface of the main body portion 2602. It is provided.
In the present embodiment, the junction box 24 and the DC / DC converter 26 are arranged between the two rows of battery module rows 36 at intervals in the extending direction of the battery module rows 36, and are arranged on the bottom wall 2802 of the tray 28. It is installed.

As shown in FIGS. 1 to 3, the fan 18 sucks the cooling air that has cooled the plurality of battery modules 34 and supplies the cooling air to the cooler 20 via the connecting duct 22.
The fan 18 is attached to the bottom wall 2802 of the tray 28 and is located between the two extending portions 40 at the center or near the center of the battery case 12.
The cooler 20 (evaporator) cools the cooling air discharged from the fan 18 and guides it to the cooling air duct 16.
Most of the cooler 20 is made of a metal material, and includes a cooler main body 2002, an inflow port 2004, and a pair of outflow ports 2006.
The cooler main body 2002 is a place where the cooling air is cooled.
The inflow port 2004 is provided in the upper part of the cooler main body 2002, and is a place where the cooling air discharged from the fan 18 flows in through the connection duct 22.
The pair of outlets 2006 are provided on both sides of the lower portion of the cooler main body 2002, and are locations where the cooling air cooled by the cooler main body 2002 flows out, and are connected to the cooling air duct 16.

The connection duct 22 is a position where the fan 18 and the cooler 20 are connected. As shown in FIG. 6, the connecting duct 22 has a rectangular shape whose cross section is horizontally long in the width direction of the tray 28, and as shown in FIG. 3, the tray 28 A laterally extending portion 2202 extending in the longitudinal direction and a vertically extending portion 2204 extending in the vertical direction are included.
One end of the laterally extending portion 2202 is connected to the discharge port 1802 of the fan 18, and the laterally extending portion 2202 extends from the discharge port 1802 in the longitudinal direction of the tray 28 below the DC / DC converter 26 toward the cooler 20. However, a part of the upper surface of the laterally extending portion 2202 includes the lower surface of the DC / DC converter 26 and the heat radiation fins 2604.
Therefore, the lower surface of the DC / DC converter 26 is cooled by the cooling air passing through the laterally extending portion 2202.
One end of the vertically extending portion 2204 is connected to the other end of the horizontally extending portion 2202, extends upward between the cooler 20 and the DC / DC converter 26, and is connected to the inflow port 2004 of the cooler 20. The vertically extending portion 2204 is made of a synthetic resin material having an insulating property.

As shown in FIGS. 1 and 2, the cooling air duct 16 includes an extending portion 40 and a curved portion 42 connected to the upstream end of the extending portion 40, and is composed of a pair of outlets of the cooler 20. A pair of extending portions 40 are connected to 2006 via curved portions 42, respectively.
As shown in FIGS. 1, 7, and 8, each extending portion 40 has a rectangular shape whose cross section is elongated in the vertical direction, and is outward in the tray width direction among the wall portions constituting the extending portion 40. A plurality of rectangular blowout openings 4004 for blowing cooling air are provided on the located outer wall 4002 at intervals in the extending direction of the extending portion 40.
The blowout openings 4004 face the inner end faces of the plurality of battery modules 34 forming each row in the tray width direction, and face the inner end faces of the plurality of battery cells 38 supported by the module housings in the tray width direction. doing.
Further, as shown in FIGS. 1, 2, and 5, a sealing material 44 made of a rectangular frame-shaped foam rubber surrounding the periphery of the blowout opening 4004 is adhered to the portion of the outer wall 4002 around the blowout opening 4004. The sealing material 44 is crushed between the outer wall 4002 and the frame-shaped module housing, so that the cooling air blown out from the blowout opening 4004 is supported by the module housing in the adjacent battery cells 38. It is designed to be reliably supplied to the gaps between the side surfaces located at both ends in the thickness T direction.

In the present embodiment, the cooling air duct 16 is composed of a synthetic resin material having an insulating property and a metal material.
More specifically, as shown in FIG. 1, the curved portion 42 and a part 40A of the extending portion 40 following the curved portion 42 are formed by combining a synthetic resin material, and a part 40A of the extending portion 40 is formed. The remaining portion 40B excluding the above is made of a metal material.
That is, the curved portion 42 is formed of a wall portion made of a synthetic resin material.
Further, the outer portion 40A1 in the tray width direction of a part 40A of the extending portion 40 following the curved portion 42 is made of sheet metal obtained by plastic working a metal plate, and the inner portion 40A2 in the tray width direction is formed of a synthetic resin material. ..
That is, at least a portion of the cooling air duct 16 located on the DC / DC converter 26 side is made of an insulating synthetic resin material, and the remaining portion 40B of the extending portion 40 is made of sheet metal. ..
This is because it is cost-effective to form the curved portion 42 by molding using a synthetic resin material because of its shape, and the remaining portion 40B has a simple shape in which flat surfaces are combined, so that it is a sheet metal. This is because it is cost-effective to form using.

It goes without saying that the curved portion 42 and the extending portion 40 may be all made of a synthetic resin material, or may be made entirely of sheet metal.
If the extending portion 40 is made of a synthetic resin material, or if the portion of the extending portion 40 located at least on the electrical equipment side is made of a synthetic resin material, the battery case 12 is deformed inward in the vehicle width direction at the time of a vehicle collision. When such an impact load is applied, the battery module 34 is displaced inward in the vehicle width direction, and when the extending portion 40 is deformed and approaches the electrical equipment, the electrical equipment and the cooling air duct 16 are electrically connected. It is possible to avoid frequent contact, which is advantageous in protecting electrical equipment.
Further, when the extending portion 40 is made of sheet metal, the rigidity of the extending portion 40 is increased. Therefore, when the battery case 12 receives an impact load that deforms inward in the vehicle width direction, the extending portion 40 becomes By receiving the impact load, the displacement of the battery module 34 inward in the vehicle width direction is suppressed, which is advantageous in protecting the electrical equipment.

Next, the action and effect will be described.
When the vehicle power supply device 10 operates, the electric power output from each battery module 34 is supplied to the vehicle drive motor, and is supplied to the accessories via the DC / DC converter 26, each battery cell is supplied. The 38 and the DC / DC converter 26 generate heat.
Alternatively, when the battery cells 38 of each battery module 34 are charged from a charging device outside the vehicle, each battery cell 38 generates heat.
In this case, when the fan 18 operates, the air in the battery case 12 is sucked and reaches the cooler 20 via the connection duct 22, and the air cooled by the cooler 20 is supplied to the cooling air duct 16 as cooling air. Will be done.
The cooling air supplied to the pair of extending portions 40 of the cooling air duct 16 is supplied to the gap between the battery cells 38 through the blowout opening 4004 of the extending portion 40.
The battery cells 38 are cooled by the cooling air passing through the gaps between the battery cells 38.
The cooling air that has passed through the battery cell 38 reaches the space S1 between the pair of extending portions 40, is eventually sucked by the fan 18, and is supplied to the cooler 20 via the connecting duct 22.
At this time, the DC / DC converter 26 is cooled by supplying the cooling air flowing through the connection duct 22 to the heat radiation fins 2604.
Since the cooling air flowing through the connection duct 22 is the cooling air after cooling the battery cell 38, the temperature is higher than the cooling air cooled by the cooler 20, but the temperature is DC higher than the temperature of the battery cell 38. Since the temperature of the / DC converter 26 is higher, the cooling efficiency is improved by cooling the DC / DC converter 26 with the cooling air after cooling the battery cell 38 in this way.
The cooling air is circulated inside the battery case 12 in this way to cool the battery cell 38 and the DC / DC converter 26.

According to the present embodiment, the cooling air duct 16 is provided with two extending portions 40 extending along each of the two battery module rows 36 between the two battery module rows 36, and the electrical equipment is provided with two. It was placed between the two extending portions 40.
Therefore, even if the impact load at the time of a collision is input to the battery case 12 and deforms inward in the vehicle width direction, and the battery module 34 is further displaced inward in the vehicle width direction, the extending portion 40 extends outward in the vehicle width direction of the electrical equipment. Is located, the extending portion 40 receives the impact load, which is advantageous in protecting the electrical equipment.

Further, in the present embodiment, since the electrical equipment is a junction box 24 for operating the battery module 34 and a DC / DC converter 26 for converting the output voltage of the battery module 34, the electrical equipment to which a high voltage is applied is applied. It is advantageous in trying to protect the battery.

Further, in the present embodiment, the fan 18 that sucks the cooling air that has cooled the plurality of battery modules 34 is located between the two extending portions 40 and in the center or the center of the battery case 12 in a plan view. It is located in the vicinity.
Therefore, the pressure loss received by the cooling air flowing from each part in the battery case 12 toward the fan 18 can be made uniform as compared with the case where the fan 18 is arranged at the end portion away from the center of the battery case 12. , The cooling air can be smoothly circulated inside the battery case 12, which is advantageous in improving the cooling efficiency.

In the present embodiment, the configuration in which the extending portion 40 is provided between the two battery module rows 36 provided at intervals in the direction orthogonal to the longitudinal direction in the plan view has been described. An extending portion 40 may be provided between the two battery module rows 36 along each of the two battery module rows 36. For example, two battery module rows provided at intervals in the vertical direction of the battery case 12. The extension portion 40 may be provided between the 36s.
Further, although the case where the battery module rows 36 are arranged in two rows has been described, the battery module rows 36 may be arranged in three or more rows, that is, the two battery module rows 36 are arranged between the two battery module rows 36. Two extending portions 40 extending along each of the above may be provided, and the electrical equipment may be arranged between the two extending portions 40.
Further, in the present embodiment, the case where the cooling fluid is the cooling air has been described, but the case where the cooling fluid is the cooling water can also be applied. In this case, the cooling passage 16 is not a cooling air duct, but a cooling water channel, and the fan is a pump.
Further, in the present embodiment, the electrical equipment is described as the junction box 24 and the DC / DC converter 26, but the present invention is not limited to this, and any electrical equipment installed in the battery pack may be used, and a current sensor and an electric leakage may occur. It may be a sensor or a BMS (battery management system).

10 Vehicle power supply 12 Battery case 16 Cooling air duct (cooling passage)
18 Fan 20 Cooler 24 Junction box (electrical equipment)
26 DC / DC converter (electrical equipment)
34 Battery module 36 Battery module row 38 Battery cell 40 Extension

Claims (5)

A row of battery modules in which multiple battery modules are arranged in one direction,
A cooling passage that supplies a cooling fluid to the battery module,
Electrical equipment electrically connected to the battery module and
A battery cooling structure for a vehicle including the battery module, the cooling passage, and a battery case for accommodating the electrical equipment.
At least two battery module rows are provided at intervals in a direction orthogonal to the longitudinal direction thereof.
The cooling passage comprises two extension portions extending along each of the two battery module rows between the two battery module rows.
The electrical equipment is arranged between the two extending portions.
The battery cooling structure of the vehicle is characterized by this. The electrical equipment includes at least one of a junction box for operating the battery module and a DC / DC converter for converting the output voltage of the battery module.
The vehicle battery cooling structure according to claim 1. At least a portion of the cooling passage located on the electrical equipment side is made of an insulating material.
The vehicle battery cooling structure according to claim 1 or 2. The cooling passage is made of metal,
The vehicle battery cooling structure according to claim 1 or 2. The cooling fluid is cooling air,
A fan that sucks the cooling air that has cooled the plurality of battery modules, and
A cooler that cools the cooling air discharged from the fan and guides the cooling air to the cooling passage is provided.
The fan is located between the two extension portions and at the center or near the center of the battery case.
The vehicle battery cooling structure according to any one of claims 1 to 4, wherein the vehicle battery is cooled.

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