JP2004306726A - Battery pack cooling structure - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To effectively cool a battery and an electric apparatus attached to the battery. <P>SOLUTION: This battery pack 1000 includes a battery part 1100 wherein 30 of battery modules having six battery cells connected in series are stacked, an accessory member part constituted of a DC/DC converter 2000 and electrical equipment (a battery ECU, a system main relay) 2500, and a crossflow fan 4000 having a blade longer at least than a total length of the length of the battery module along the stacking direction and the length of the DC/DC converter. The crossflow fan 4000 supplies cooing air to a space between the battery modules and a space between the battery part 1100 and the DC/DC converter 2000. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to an electric device mounted on a vehicle, and more particularly, to a secondary battery used for an electric vehicle (EV), a hybrid vehicle (HV), and the like.
[0002]
[Prior art]
Electric vehicles, hybrid vehicles, and fuel cell vehicles that obtain driving force of the vehicle by an electric motor are equipped with a secondary battery. The electric vehicle drives the electric motor using the electric power stored in the secondary battery to drive the vehicle. The hybrid vehicle drives the electric motor using the electric power stored in the secondary battery to drive the vehicle, or assists the engine with the electric motor to drive the vehicle. A fuel cell vehicle drives a vehicle by driving an electric motor using electric power from a fuel cell or drives an electric motor using electric power stored in a secondary battery in addition to electric power from this fuel cell to drive a vehicle. Or
[0003]
Since these secondary batteries require high voltage and high output, a battery module in which about 30 battery modules of about 1.2 V such as nickel-metal hydride batteries are connected in series and about 30 pieces thereof are connected in series is used. Forming a pack. In an electric vehicle, a hybrid vehicle, and the like, such a secondary battery, which has not been mounted on a conventional vehicle using only an internal combustion engine as a driving source of the vehicle, must be mounted. For vehicles, consider the placement of secondary batteries, which are large in electrical equipment mounted on vehicles, from the viewpoints of effective use of cabin space and luggage space and ensuring safety in the event of a collision. There is a need.
[0004]
In this study, it is necessary to consider the size (height, length of the vehicle in the width direction, length of the vehicle in the front-rear direction) of the secondary battery, or to consider cooling of the secondary battery. There. The secondary battery forms a battery pack including an electric cooling fan, a system main relay, a battery ECU (Electronic Control Unit), and the like.
[0005]
Conventionally, such a secondary battery, as shown in FIG. 7, draws the battery 100 from the upper part to the lower part of the battery by sucking the air in the passenger compartment from a cooling air supply duct 200 with a cooling fan 300. It was cooled so that it flowed and was discharged from the exhaust duct 400.
[0006]
Further, in addition to such a battery pack, a PCU (Power) for supplying power to the motor from the battery pack or charging the battery pack with the generated power by making the motor function as a generator during regenerative braking. It is necessary to mount an electric device called a Control Unit on the vehicle. The PCU includes an inverter and a DC / DC converter.
[0007]
Japanese Patent Laying-Open No. 11-180168 (Patent Document 1) discloses a cooling structure that can effectively cool both a battery and an electric component housed in a battery box with cooling air from a common cooling fan. In this cooling structure, a battery for supplying power to a motor and electric components connected to the motor or the battery are housed in a battery box, and cooling air from a cooling fan is supplied to a cooling air passage formed inside the battery box. In the electric vehicle that cools the battery and the electric components, the passage cross-sectional area of the second cooling air passage that cools the electric components is set smaller than the passage cross-sectional area of the first cooling air passage that cools the battery.
[0008]
According to this cooling structure, the cooling air supplied from the cooling fan to the first cooling air passage having a large passage cross-sectional area effectively cools the battery having a large thermal resistance while flowing through the first cooling air passage at a low flow velocity. The cooling air supplied from the cooling fan to the second cooling air passage having a small passage cross-sectional area can effectively remove electric components having a small thermal resistance while flowing through the second cooling air passage at a high flow rate. Can be cooled. In this way, it is possible to simultaneously cool batteries and electric components having different thermal resistances while using a common cooling fan.
[0009]
[Patent Document 1]
JP-A-11-180168
[Problems to be solved by the invention]
However, in the battery pack as shown in FIG. 7, the volume including the cooling fan and the like becomes too large, and hinders effective use of the space of the vehicle.
[0011]
Further, the cooling structure disclosed in Patent Literature 1 cools the battery on the upstream side of the flow of the cooling air (on the side of the cooling fan that pushes out cooling air) and cools the electric equipment on the downstream side of the cooling air. Since the electric equipment is cooled by the generated cooling air, the cooling efficiency of the electric equipment is not preferable.
[0012]
The present invention has been made to solve the above-described problems, and an object of the present invention is to provide a battery pack including a battery and electric devices such as a DC / DC converter and a system main relay, in which a large battery pack is used. An object of the present invention is to provide a cooling structure for a battery pack that satisfactorily cools both a battery and an electric device without causing a problem.
[0013]
[Means for Solving the Problems]
A cooling structure for a battery pack according to a first aspect of the present invention is a cooling structure for a battery pack including a battery unit having a battery module and an accessory unit including an electric component attached to the battery unit. . The cooling structure includes a flow passage for flowing the cooling medium in parallel with the battery unit and the accessory unit, and a cooling fan for flowing the cooling medium through the flow passage.
[0014]
According to the first aspect, the cooling fan allows the cooling medium to flow in parallel to the battery unit and the accessory unit via the flow passage, so that both the battery module and the electric component can be efficiently cooled.
[0015]
In the battery pack cooling structure according to the second invention, in addition to the configuration of the first invention, the battery unit is a battery in which a plurality of battery modules each having a plurality of rectangular battery cells connected in series are stacked. is there.
[0016]
According to the second aspect, the cooling fan allows the cooling medium to flow in parallel to the battery unit and the accessory unit, in which a plurality of battery cells are connected in series, through the flow passage, so that the battery module and the electric component Both can be cooled efficiently.
[0017]
In the battery pack cooling structure according to the third invention, in addition to the structure of the first or second invention, the battery section is formed by stacking the battery modules with a predetermined gap therebetween, and the flow passage is formed in the gap. A flow path for guiding the cooling medium and a flow path for guiding the cooling medium to the electric component are included.
[0018]
According to the third aspect, in the battery section, the cooling medium can cool the battery module through the gap between the battery modules.
[0019]
In the cooling structure for a battery pack according to a fourth aspect, in addition to the configuration of the first or second aspect, the flow path includes a flow path for guiding the cooling medium to the gap and a flow path for guiding the cooling medium to the electric component. , And a flow path leading between the battery module and the electric component.
[0020]
According to the fourth aspect, the battery modules and the electric components can be efficiently cooled by the cooling medium flowing through the three flow paths.
[0021]
In the cooling structure for a battery pack according to a fifth aspect, in addition to the configuration of any one of the first to fourth aspects, the cooling fan is a fan that pushes out a cooling medium.
[0022]
According to the fifth aspect, a sirocco fan or a cross flow fan is attached in an extruded manner, a cooling medium can be supplied to the flow passage, and cooling can be performed efficiently and without increasing the size of the battery pack.
[0023]
In the cooling structure for a battery pack according to a sixth aspect, in addition to the configuration of any one of the first to fourth aspects, the cooling fan is a fan that sucks a cooling medium.
[0024]
According to the sixth aspect of the present invention, the sirocco fan or the cross flow fan is attached in a suction manner so that the cooling medium can be supplied to the flow passage, and the cooling can be efficiently performed without increasing the size of the battery pack.
[0025]
In a cooling structure for a battery pack according to a seventh aspect, in addition to the configuration of any one of the first to sixth aspects, a cooling fan is arranged on the electric component side.
[0026]
According to the seventh aspect, an electric component having a small amount of heat is provided on the cooling fan side, so that the battery module can be cooled more efficiently.
[0027]
In the cooling structure for a battery pack according to an eighth aspect, in addition to the configuration of any one of the first to seventh aspects, one cooling fan is provided for the battery pack.
[0028]
According to the eighth invention, for example, a battery module and an electric device are provided side by side in the longitudinal direction of the cross flow fan, so that a plane flow from the cross flow fan can flow to the battery module and the electric device, Can be cooled without upsizing.
[0029]
In the battery pack cooling structure according to the ninth aspect, in addition to the configuration of any one of the first to eighth aspects, the electric component includes a DC / DC converter and cools the battery pack according to the tenth aspect. In construction, the electrical components include the system main relay.
[0030]
According to the ninth aspect, the DC / DC converter mounted as an electrical component can be efficiently cooled, and according to the tenth aspect, the system main relay mounted as an electrical component can be efficiently cooled.
[0031]
In the cooling structure for a battery pack according to an eleventh aspect, in addition to the configuration of any one of the first to tenth aspects, the cooling fan is one of a sirocco fan and a cross flow fan.
[0032]
According to the eleventh aspect, a small and lightweight sirocco fan is provided, or the sirocco fan is provided along with the battery module and the electric device in the longitudinal direction of the cross flow fan, so that the battery pack can be cooled without being enlarged.
[0033]
BEST MODE FOR CARRYING OUT THE INVENTION
Hereinafter, embodiments of the present invention will be described with reference to the drawings. In the following description, the same components are denoted by the same reference numerals. Their names and functions are the same. Therefore, detailed description thereof will not be repeated.
[0034]
The cooling structure of the battery pack according to the present embodiment will be described with reference to FIG.
[0035]
As shown in FIG. 1, the battery pack 1000 includes a battery unit 1100 in which a predetermined number of battery modules are stacked, a DC / DC converter 2500 that is an electric device attached to the battery unit 1100, and electric devices (a battery ECU and a system). Main relay) 2500.
[0036]
The battery unit 1100 is formed by stacking, for example, 30 battery modules in which six 1.2-volt nickel-metal hydride batteries are connected in series at predetermined intervals (cooling air passages). As shown in FIG. 1, in this battery pack 1000, a cross flow fan 4000 is provided in a direction perpendicular to the stacking direction of the battery modules. The cross flow fan is a fan that can obtain a uniform plane flow perpendicular to the direction of suction of the cooling air as a cooling medium, and has a feature that its volume is small despite a large amount of cooling air.
[0037]
The cross flow fan 4000 is rotated by a cross flow fan motor 3000. By changing the polarity of the cross-flow fan motor 3000, the cross-flow fan 4000 can be of a type that pushes out cooling air or a type that sucks in cooling air. Further, unlike the conventional case shown in FIG. 7, the cooling air is not cooled from the upper part to the lower part of the battery module in a down-flow type or an up-flow type. There is no. Therefore, the height dimension of the battery pack can be reduced. The advantage of this small dimension in the height direction is a very advantageous point when the battery pack 1000 is mounted under a seat of a vehicle or the like.
[0038]
Referring to FIG. 2, a plan view of the battery pack according to the present embodiment is shown. As shown in FIG. 2, the battery pack 1000 is configured such that the crossflow fan 4000 is formed in an extruded form to cool the battery unit 1100, the DC / DC converter 2000, and the electrical equipment (battery ECU, system main relay) 2500. It is. The cross flow fan 4000 is rotated by the cross flow fan motor 3000 in the direction in which the planar flow is extruded, and cools the battery through the battery module interval of the battery unit 1100. Further, DC / DC converter 2000 and electrical equipment (battery ECU, system main relay) 2500 are cooled by cross flow fan 4000.
[0039]
Thus, the length of the blades of cross flow fan 4000 is at least longer than the length of battery unit 1100 and DC / DC converter 2000 arranged. Therefore, the cooling air extruded from cross flow fan 4000 passes through cooling passage 4010 to uniformly cool battery unit 1100 and DC / DC converter 2000. As a result, the battery unit 1100 and the DC / DC converter can be uniformly cooled with a compact design. Further, in addition to DC / DC converter 2000, electrical equipment (battery ECU, system main relay) 2500 may be cooled.
[0040]
FIG. 3 shows a battery pack 1010 according to a modification of the present embodiment.
As shown in FIG. 3, by rotating the cross flow fan 4000 in the reverse direction, the battery unit 1100 and the DC / DC converter 2000 are cooled in a suction manner. As shown in FIG. 3, cross flow fan 4000 draws cooling air from battery battery 1100 and DC / DC converter 2000 into cross flow fan 4000 from the side opposite to cross flow fan 4000. Like the battery pack 1000 shown in FIG. 2, in the battery pack 1010 shown in FIG. 3, the length of the blades of the cross flow fan is at least longer than the length in which the battery unit 1100 and the DC / DC converter 2000 are arranged. Due to the lengthening, cooling air can be uniformly sucked from the battery unit 1100 and the DC / DC converter 2000.
[0041]
FIG. 4 shows a battery pack 1020 according to a modification of the present embodiment.
As shown in FIG. 4, the battery pack 1020 according to the present modification uses a sirocco fan 4100 instead of using the cross flow fan shown in FIGS.
[0042]
As shown in FIG. 4, a battery pack 1020 according to the present modification has a sirocco fan 4100 and a cooling air flow path 4200. The cooling air passage 4200 has a function of uniformly flowing the cooling air supplied from the sirocco fan 4100 to the battery unit 1100 and the DC / DC converter 2000. Also in the present modified example, since the cooling air is not supplied to the battery module in the form of downflow or upflow as in the related art, the height dimension of the battery pack 1020 can be reduced. In addition, cooling can be efficiently performed using a sirocco fan having a small volume.
[0043]
FIG. 5 shows a battery pack 1030 according to a modification of the present embodiment.
As shown in FIG. 5, a battery pack 1030 according to the present modification is configured such that the sirocco fan 4100 of the battery pack 1020 shown in FIG. The sirocco fan 4102 has a different installation direction from that of the sirocco fan 4100 shown in FIG. By the sirocco fan 4102, the cooling air that has passed through the gap between the battery modules of the battery unit 1100 and the DC / DC converter 2000 passes through the cooling air flow path 4202 and is sucked by the sirocco fan 4102. In the battery pack 1030 according to the present modification, similarly to the battery pack 1020 shown in FIG. 4 described above, the height dimension of the battery pack 1030 can be reduced.
[0044]
FIG. 6 shows a modification common to the battery packs 1000 to 1030 shown in FIGS. As shown in FIG. 6, in the battery pack according to this modification, a cooling fin 2600 and a cooling fin 2700 are provided in a housing containing a DC / DC converter 2000 and electric equipment (battery ECU, system main relay) 2500.
[0045]
As shown in FIG. 6, a housing containing a DC / DC converter 2000 and electrical equipment (battery ECU, system main relay) 2500 has cooling fins 2600 provided on the upper surface thereof and cooling fins provided on the side surfaces thereof. 2700 may be provided, or one of them may be provided. In particular, the cooling fins 2700 provided on the side can be efficiently cooled by cooling air between the cooling fins 2700 and the battery unit 1100.
[0046]
As described above, according to the cooling structure of the battery pack according to the present embodiment, a battery unit in which a plurality of battery modules in which rectangular battery cells (minimum unit of battery) are connected in series is stacked, The DC / DC converter, the system main relay, and the battery ECU, which are the attached electric components, are cooled in parallel. This structure is specifically composed of a cross flow fan, a sirocco fan and a cooling air flow path. With such a configuration, the battery unit and the electric equipment attached to the battery unit can be uniformly and efficiently cooled, and the size (particularly, the height direction) of the battery pack can be reduced. .
[0047]
The embodiments disclosed this time are to be considered in all respects as illustrative and not restrictive. The scope of the present invention is defined by the terms of the claims, rather than the description above, and is intended to include any modifications within the scope and meaning equivalent to the terms of the claims.
[Brief description of the drawings]
FIG. 1 is an external view of a battery pack according to an embodiment of the present invention.
FIG. 2 is a plan view (part 1) of the battery pack according to the embodiment of the present invention.
FIG. 3 is a plan view (part 2) of the battery pack according to the embodiment of the present invention.
FIG. 4 is a plan view (part 3) of the battery pack according to the embodiment of the present invention.
FIG. 5 is a plan view (part 4) of the battery pack according to the embodiment of the present invention.
FIG. 6 is an external view of a battery pack according to a modification of the embodiment of the present invention.
FIG. 7 is an external view of a battery pack according to a conventional technique.
[Explanation of symbols]
100 battery, 200 air supply duct, 300 cooling fan, 400 exhaust duct, 1000, 1010, 1020, 1030 battery pack, 1100 battery unit, 2000 DC / DC converter, 2500 electric equipment (battery ECU, system main relay), 2600, 2700 cooling fins, 3000 cross flow fan motors, 4000 cross flow fans, 4010, 4200, 4202 cooling air passages, 4100 sirocco fans.

Claims (11)

A cooling structure for a vehicle battery pack,
The battery pack includes a battery unit including a battery module, and an accessory unit including an electric component attached to the battery unit,
A flow passage for flowing a cooling medium in parallel with the battery unit and the accessory unit;
A battery fan cooling structure including: a cooling fan that circulates the cooling medium through the flow passage. 2. The battery pack cooling structure according to claim 1, wherein the battery unit includes a plurality of battery modules each including a plurality of rectangular battery cells connected in series. 3. The battery unit is stacked with the battery module provided with a predetermined gap,
3. The battery pack cooling structure according to claim 1, wherein the flow path includes a flow path that guides the cooling medium to the gap and a flow path that guides the cooling medium to the electric component. 4. The flow path includes a flow path that guides a cooling medium to the gap, a flow path that guides a cooling medium to the electric component, and a flow path that guides between the battery module and the electric component. 3. The battery pack cooling structure according to 2. The battery pack cooling structure according to any one of claims 1 to 4, wherein the cooling fan is a fan that extrudes a cooling medium. The battery pack cooling structure according to any one of claims 1 to 4, wherein the cooling fan is a fan that sucks a cooling medium. The battery pack cooling structure according to any one of claims 1 to 6, wherein the cooling fan is arranged on the electric component side. The battery pack cooling structure according to claim 1, wherein one cooling fan is arranged for the battery pack. The battery pack cooling structure according to any one of claims 1 to 8, wherein the electric component includes a DC / DC converter. The battery pack cooling structure according to any one of claims 1 to 8, wherein the electric component includes a system main relay. The battery pack cooling structure according to any one of claims 1 to 10, wherein the cooling fan is one of a sirocco fan and a cross flow fan.

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