Battery pack apparatus with control section

A battery pack apparatus including a battery pack having a plurality of rechargeable batteries arranged in parallel, with a cooling medium passage interposed therebetween, a cooling medium feeding device for feeding a cooling medium through the cooling medium passages, and a control section for controlling the charge and discharge of the battery pack. In this configuration, the battery pack apparatus is divided into a first unit including the battery pack and the cooling medium feeding device and a second unit having the control section accommodated in a case. The battery pack of the first unit is connected with the control section of the second unit by means of a harness or metallic connecting member.

The present disclosure relates to subject matter contained in priority Japanese Patent Application No. 2003-110964, filed on Apr. 16, 2003, the contents of which is herein expressly incorporated by reference in its entirety.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to a battery pack apparatus including a battery pack having a plurality of rechargeable batteries and a control section for controlling the charge and discharge of the battery pack.

2. Description of the Related Art

In a battery pack having a plurality of rechargeable batteries, the battery temperature tends to rise due to heat generation caused by charge and discharge of the batteries, which induces decrease of the battery output, the charge/discharge efficiency and the battery lifetime. To cope with such problem, it has been conventionally known that a battery pack apparatus includes a battery pack composed of a plurality of rechargeable batteries arranged in parallel, with cooling medium passages interposed therebetween and a device for feeding cooling medium through the cooling medium passage.

As another known apparatus,FIG. 4shows a configuration of a battery pack apparatus in which a combination of such a battery pack and a cooling medium feeding device is further provided with a control section for controlling the charge and discharge of the battery pack. Referring toFIG. 4, a battery pack arrangement space32and a control section arrangement space33are set side by side along a longitudinal direction inside a case31, and a battery pack34is disposed in an inclined posture in the battery pack arrangement space32. A cooling medium feeding device36is connected to one end of a feeding space35that is defined between one side face of the battery pack34and the opposing wall of the case31. A discharging space37is defined between another side face of the battery pack34and the opposing wall of the case31, and an end of this discharging space37is connected to one end of a discharging passage38provided in the control section arrangement space33while the other end of the discharging passage38is opened to the outside of the case31. Further, there is provided, in the discharging passage38, a cooling fin40thermally coupled to a control section39arranged within the control section arrangement space33for performing heat exchange with cooling medium (see Japanese Patent Laid-Open Publication No. Hei 11-180168, for example).

However, in a battery pack apparatus such as disclosed in Japanese Patent Laid-Open Publication No. Hei 11-180168, the discharging passage38in the control section arrangement space33must be completely sealed to prevent cooling medium from entering the control section arrangement space33. Otherwise, hydrogen gas or alkali mist emitted from the battery pack34or dust or similar will enter the control section39to cause adverse effects. Further, according to this conventional configuration in which heat from the control section39is dissipated to the cooling medium by means of the cooling fin40, the heat transfer efficiency is low and hence the cooling efficiency is poor. Additionally, the provision of the cooling fin40increases the weight and cost.

SUMMARY OF THE INVENTION

In light of the foregoing problems, an object of the present invention is to provide a battery pack apparatus that is secure from adverse effects caused by a control section for controlling the charge and discharge being brought into contact with gas or mist emitted from a battery pack, and that is capable of cooling the control section effectively.

A battery pack apparatus according to the present invention includes a battery pack having a plurality of rechargeable batteries arranged in parallel, with a cooling medium passage interposed therebetween, a cooling medium feeding device for feeding a cooling medium through the cooling medium passage, and a control section for controlling the charge and discharge of the battery pack. The battery pack apparatus is divided into a first unit including the battery pack and the cooling medium feeding device and a second unit having the control section accommodated in a case, the battery pack of the first unit being connected to the control section of the second unit by means of a harness or metallic connecting member.

According to such a configuration, in which the battery pack apparatus is divided into the first unit having the battery pack and the second unit having the control section, there is no risk that hydrogen gas or alkali mist emitted from the rechargeable batteries enters the control section and the control section is adversely affected thereby, and hence high security is ensured. Also, since the first and second units are separate entities, the battery pack apparatus can be laid out with increased flexibility when mounted.

Further, a switch for turning electricity on and off may be provided at an input/output portion of the battery pack in the first unit, so that installation of the battery pack apparatus is performed safely and with good workability by connecting the first and second units with the switch opened by using the harness or metallic connecting member and then closing the switch.

Further, a vent hole may be provided at a lower part of the case of the second unit while an exhaust port being provided at the top of the case, so that the control section is directly cooled by natural convection of cooling air flowing in through the vent hole and flowing out through the exhaust port, and thus the control section is cooled effectively.

Still further, a vent hole may be provided at a lower part of the case of the second unit while an exhaust port being provided at the top of the case, and the exhaust port may be connected to a downstream side passage of the cooling medium passage in the cooling medium feeding device, so that cooling air is forcibly supplied to the inside of the case by the cooling medium feeding device and hence the control section is cooled still more effectively.

While novel features of the invention are set forth in the preceding, the invention, both as to organization and content, can be further understood and appreciated, along with other objects and features thereof, from the following detailed description and examples when taken in conjunction with the attached drawings.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

Now, a battery pack apparatus according to an embodiment of the present invention will be described with reference toFIGS. 1 and 2.

InFIG. 1, the reference numeral1denotes a battery pack apparatus serving as a driving power source for electric vehicles including hybrid powered vehicles and includes a first unit11and a second unit12. The first unit11has a battery pack5composed of ten to thirty flat prismatic rechargeable batteries2(e.g. nickel-metal hydride rechargeable batteries equipped with a return safety vent) with a cooling medium passage3interposed between the long side faces of each pair of adjacent rechargeable batteries. The train of the rechargeable batteries2is held with a pair of end plates4arranged at the opposite ends of the train, and the thus obtained set is fixed integrally by a binding member (not shown). The second unit12includes a control section8, that is composed of a controller6and a relay7, for controlling the charge and discharge of the battery pack5and is accommodated in a case9. The control section8is connected with the battery pack5by means of a harness or metallic connecting member10.

Each of the rechargeable batteries2in the battery pack5is constituted as a battery module in which a plurality of cells (not shown) are arranged in parallel along the longitudinal direction of the long side faces of the rechargeable battery while being serially connected with one another. Terminals are provided to project from the opposite ends of the rechargeable battery for connection with the outside. The battery pack5provides a predetermined voltage by connecting sequentially the connection terminals on the opposite ends of the respective rechargeable batteries2by means of a bus bar (not shown).

In the first unit11, a feeding passage14is defined between the bottom face of the battery pack5and a lower case13for distributing and feeding the cooling medium to the cooling medium passages3, and a discharge passage16is defined between the top face of the battery pack5and an upper case15for collecting and discharging the cooling medium from the cooling medium passage3. A feeding duct17is connected to the open end of the feeding passage14, and an exhaust duct19equipped with an exhaust fan18is connected to the open end of the discharge passage16. The foregoing members constitute a cooling medium feeding device20.

In the second unit12, a case9is provided at the lower part thereof with a through hole21for passing the harness or metallic connecting member10therethrough and with a vent hole22for introducing cooling air to the inside therethrough. The case9is further provided at the top wall thereof with an exhaust port23such that the exhaust port23is positioned above the control section8that is a heat generating element.

Further, as shown inFIG. 2, the first unit11is provided with a switch25for turning electricity on and off, between the battery pack5and connection terminals24connected with the harness or metallic connecting member10.

According to the foregoing configuration, since the battery pack apparatus1is divided into the first unit11having the battery pack5and the second unit12having the control section8, there is no risk at all that hydrogen gas, alkali mist or the like emitted from the return safety vent of the rechargeable batteries2enters the control section8. This totally eliminates those risks that hydrogen gas entering the relay7of the control section8comes into contact with sparks, or alkali mist entering the controller6or relay7poses adverse effects, and hence high security is ensured. In the second unit12, additionally, outside air is introduced through the vent hole22at the lower part of the case9, while air heated by the heat generation of the control section8is discharged from the exhaust port23formed at the top of the case9, creating natural convection. Thereby, the control section8is directly cooled by the natural convection of cooling air and thus is cooled effectively.

Further, since the battery pack apparatus1is divided into the first unit11and the second unit12, which are connected by the harness or metallic connecting member10, the battery pack apparatus1can be laid out with increased flexibility when mounted. For example, the battery pack apparatus1can be mounted in the width direction of a vehicle by arranging the first unit11and the second unit12separately on either side of the width-wise and arranging the harness or metallic connecting member10to cross a center tunnel section in the middle of the width.

Further, the battery pack apparatus1can be installed safely and with good workability by opening the switch25when the first unit11and second unit12are arranged separately on a vehicle and connected with the harness or metallic connecting member10, and then closing the switch25upon completion of the connection.

Still further, the second unit12can be used commonly for various types of first units with battery packs5having different numbers of rechargeable batteries2, so that the cost for the battery pack apparatus1is decreased.

Next, a battery pack apparatus according to another embodiment of the invention will be described with reference toFIG. 3. The same elements as the first embodiment are represented by the same reference numerals and description thereof is omitted while only different elements and aspects will be described.

In this second embodiment, an exhaust port23is formed in the top wall of a case9of a second unit12and communicates with a collecting and discharge passage16of a cooling medium feeding device20by being connected through a duct26or tube.

According to this configuration, cooling air is forcibly supplied to the inside of the case9by the cooling medium feeding device20, and hence a control section8is cooled still more effectively.

It should be noted that, although the rechargeable batteries in both the embodiments above have been described as flat and prismatic, the rechargeable batteries can take a cylindrical shape and be arranged in parallel, with a cooling medium feeding passage interposed therebetween. A battery pack thus obtained is also capable of providing same effects.

According to the present invention, the battery pack apparatus is constituted by the first unit including the battery pack and the cooling medium feeding device and the second unit having the control section accommodated in the case, while the battery pack of the first unit is connected with the control section of the second unit by means of the harness or metallic connecting member. As a result, the risk is eliminated that hydrogen gas or alkali mist emitted from the rechargeable batteries might enter the control section and the control section might be adversely affected thereby, and thus high security is ensured. Further, since the battery pack apparatus is divided into the first and second units, the battery pack apparatus can be laid out with increased flexibility when mounted. Further, since the second unit can be used commonly for various types of first units with battery packs having different numbers of rechargeable batteries, the cost for the battery pack apparatus is decreased.

Although the present invention has been fully described in connection with the preferred embodiment thereof, it is to be noted that various changes and modifications apparent to those skilled in the art are to be understood as included within the scope of the present invention as defined by the appended claims unless they depart therefrom.