JPH11354166A - Battery temperature controller - Google Patents

Abstract

PROBLEM TO BE SOLVED: To regulate a battery temperature from the inside. SOLUTION: A heat sink 30 is thermally connected via an insulated heat- transfer sheet 24 with the first and second electrode connectors 16, 18 of +/- electrodes of a packed battery 8, and connecting connectors 14 for connecting batteries 10 in series. The heat sink 30 is thermally connected as the result therein with internal electrodes of the batteries 10 via the connectors 14-18 and terminals 12. A battery temperature is controlled thereby from its inside by cooling or heating the heat sink 30.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to battery temperature control when a plurality of batteries are connected and used, and more particularly, to a battery which can maintain a uniform temperature when a plurality of batteries are used as a set. It relates to a temperature control method and a battery.

[0002]

2. Description of the Related Art When a battery is used as a power source in an electric vehicle or the like, a plurality of batteries are connected in series or in parallel to obtain a required voltage and capacity. Since the performance of a battery changes depending on its temperature, unless the batteries are used while keeping the temperature of the batteries uniform, a situation occurs in which the remaining amount of electricity differs among the batteries. As a result, there is a difference in efficiency when charging is performed, so that overcharged batteries and undercharged batteries are mixed. When charging and discharging are repeated in such a state, the life of some of the batteries (or cells) expires in a short time, so that the life varies. Since an electric vehicle uses a large number of batteries, a plurality of batteries are often used as one set (assembled battery) in order to easily replace the battery. Battery life can also be significantly shorter than expected.

[0003] Conventionally, a device for keeping the temperature of a plurality of batteries uniform has been proposed.
Such an apparatus is disclosed in Japanese Patent Application Laid-Open No. 774-794 and Japanese Patent Application Laid-Open No. 5-1699981. These are intended to maintain the temperature of multiple batteries at a uniform temperature by efficiently contacting either surface of a rectangular parallelepiped battery with the outside air and devising the ventilation of such cooling air. is there.

However, according to these, when there are a plurality of batteries, a temperature difference occurs in a heat exchange medium such as air while passing between them, and it is difficult to perform uniform temperature control. Further, since the case of the battery body is usually a thick resin (plastic), even if the case itself is cooled, its thermal conductivity is poor, and it is not always suitable for effective temperature adjustment.

Japanese Patent Application Laid-Open No. 8-148187 discloses that a heat transfer plate is brought into contact with a side surface of each of a plurality of batteries and heat exchange (cooling and heating) is performed through the heat transfer plates to more effectively control the temperature of the battery. Is shown. However, since heat is exchanged through the external side surface of the battery, it is difficult to say that heat exchange efficiency is good.

[0006]

According to the present invention, the temperature of the battery is controlled by exchanging heat with the electrode inside the battery through the terminal of the battery. That is, the temperature of the battery is controlled more directly. Of course, the conventional heat exchange through the side of the battery may be used together. When used together, heat exchange occurs both inside and outside of the battery, so that extremely effective temperature control becomes possible.

More specifically, the battery temperature control device of the present invention includes heat conducting means thermally coupled to a terminal of the battery, and the heat conducting means is connected to an internal electrode of the battery via the terminal. It controls the temperature of the battery by being thermally coupled and performing heat exchange in the heat transfer means. The heat conducting means is thermally coupled to the internal electrodes via, for example, an electrode connector connected to a terminal of the battery. When a plurality of batteries are used, the terminals of the plurality of batteries are connected in series or in parallel using a connection connector, and the connection connector is thermally coupled to the heat conduction means, so that the heat conduction means is connected to the internal electrode. Thermally coupled with

[0008] In the present invention, insulating heat transfer means may be provided. This insulates the electrode connectors, the connection connectors, or the electrode connector and the connection connector from each other, and thermally couples the electrodes or the connection connector to the heat conducting means. At this time, a heating (heater) mechanism may be provided in the insulating heat transfer means to heat the battery as needed. Further, a heat exchange means for heating or cooling the heat conduction means may be provided.

It is preferable that the battery used in the present invention has its terminals thermally effectively coupled to the internal electrodes. For example, a pole connecting the terminal and the internal electrode (connection means)
It is preferable to use a material that is thicker to the extent that it extends over a majority of the internal electrodes.

[0010]

FIG. 1 is an exploded perspective view of a preferred embodiment of the present invention. FIG. 2 is a perspective view showing a battery pack 8 composed of a plurality of batteries, and FIG. 3 is a perspective view showing a state in which a connector is connected to a terminal of the battery. The battery pack according to the present invention is preferably intended for use in electric vehicles (including hybrid vehicles). In the following description, those having a correspondence are denoted by the same alphabetical suffix.

The battery pack 8 is shown here as an example composed of ten batteries 10a to 10j. Each battery has positive and negative terminals, and the terminals of adjacent batteries are arranged so that the polarity of the terminals is alternated. For example, the battery 10a minus terminal 12a- and the battery 10b plus terminal 12b + are arranged so as to be adjacent to each other. These batteries 10a to 10j are connected in series by a plurality of connectors 14a to 14i. The first electrode connector 16 is fixed to the plus terminal 12a + of the battery 10a with a screw 20, and is electrically connected. The second electrode connector 18 is fixed to the minus terminal 12j- with a screw 28 and is electrically connected. Battery pack 8 connected in series
Are used in parallel connection as needed.

The insulation heat transfer sheet (insulation heat transfer means) 22
From the heat sink (heat conduction means) 30 to the first connector 16
And the connector 14 is electrically insulated. At the same time, the insulating heat transfer sheet 22 is formed of a material having excellent heat conductivity, and thermally connects the connection connector 14, the first electrode connector 16, and the second electrode connector 18 to the heat sink 30. Further, the insulating heat transfer sheet 22 preferably has plasticity. The connector 14 to 18 and the conductive plate 2
4 are more closely adhered to each other, and the thermal bonding between them is improved.

The connectors 14, 16 and 18 are also made of a material having excellent thermal conductivity (aluminum, copper, gold, etc.) and have a shape that widens the contact surface with the insulating heat conductive sheet 22 or the conductive plate 24. It is good to form. At this time, one end 17 of the first electrode connector 16 functions as a positive electrode of the battery pack 8. One end 26 of the conductive plate 24 electrically connected to the second electrode connector 18 functions as a negative electrode of the battery pack 8.

When the conductive plate 24 is on the negative electrode side, the conductive plate 24 is grounded. For example, when the battery to which the present invention is applied is applied to an automobile, the conductive plate 24 is connected to the chassis of the vehicle body.
And there is no potential difference between the chassis. At this time, the conductive plate 24
Are arranged outside the first electrode connector 16 and the connector 14 having a positive potential so as to cover them, so that the risk of electric shock for the user can be reduced and the safety is high.

The holding plate 3 is provided on the side of the battery pack 8.
4 and 36 are provided. These plates sandwich a plurality of batteries by tightening a pair of rods 40 (only the front side is shown) with screws 38 or the like, and hold the battery 10. Between each of the plurality of batteries 10a to 10j,
The heat transfer plate 42 is inserted. The heat transfer plate 42 enables heat exchange from the side surface of each of the batteries 10a to 10j. The heat exchange using the heat transfer plate is described in detail in, for example, the above-mentioned Japanese Patent Application Laid-Open No. 8-148187.

The heat sink 30 is fixed to the holding plates 34 and 36 with screws 32 or the like. As a result, the heat sink 30 includes the insulating heat transfer sheet 22 and the connectors 14 and 16.
And 18 and the terminals 12 of the batteries 10a to 10j, and are thermally coupled to the internal electrodes of the respective batteries.
A plurality of fins (heat exchange means) 44 are provided on the heat sink 30.
Is provided, and heat is exchanged by supplying wind between the fins 44. For example, a blower fan (not shown) may be provided on the fins 44 (heat exchange in this case is usually cooling of the battery). However, as described later, the heat sink 30 may be used not only for cooling but also for heating the battery by supplying hot air, for example. As a method for supplying hot air, for example, a well-known technique related to an automobile may be used. Further, as a method of heat exchange, other well-known techniques such as heat exchange using water as a medium as well as the method using air as a medium as shown in the example may be used.

Heat generation (heater) is applied to the insulating heat transfer sheet 22.
A function may be provided to heat the battery. Heating the battery is effective for use in cold regions or early mornings. As such an insulating heat transfer sheet, a Samicon heater manufactured by Sakaguchi Electric Heat Co., Ltd. may be used. In this case, a pattern of a heating element is formed on silicon rubber or a heat-resistant film, and a desired heat generation distribution is enabled. That is, by forming the heating element pattern in accordance with the temperature distribution of the battery, the temperature distribution of the battery can be controlled to a desired state. At this time, by providing a heat insulating material only in a portion of the silicon rubber or the heat-resistant film on which the pattern of the heating element is provided, heat is mainly released in a direction in which the heating element is exposed, while heat is released in the opposite direction. , And efficient battery heating can be realized. At the same time, with respect to the portion of the silicon rubber or the heat-resistant film that does not have a heat insulating material, a material having good heat conductivity is used to thermally couple the heat sink 30 and the connectors 14 to 18 when the heating element is not heated. To maintain good properties. When the battery is heated using the insulating heat transfer sheet 22, it is preferable to supply the heat from the heat sink 30 to the battery by supplying hot air to the heat sink 30 at the same time.

FIG. 4 is an exploded perspective view showing another embodiment according to the present invention. Components corresponding to those in FIG. 1 are denoted by the same reference numerals. There is no conductive plate 24 as compared with FIG. Further, the shape of the second connector 18 is changed, and one end 19 of the second connector 18 functions as a negative electrode of the battery pack 8.
Further, with these changes, the shape of the insulating heat transfer sheet 22 is also changed. However, even in the case of FIG. 4, the point that the heat sink 30 is thermally coupled to the internal electrode of each battery is common. Also, the heating (heater) function may be provided on the insulating heat transfer sheet 22 so as to be used for heating the battery 10.

FIG. 5 is a partially broken perspective view showing an example of a battery more suitable for use in the present invention. Also, FIG.
It is a partial cutaway perspective view of an example of a normal battery. The positive internal electrode 6 and the negative internal electrode 4 inside the battery are separated by a separator 5. The terminal 12 of the battery 10
It is connected to the internal electrode 4 or 6 via the pole 7.

In the present invention, a terminal having a normal shape as shown in FIG. 6 may be used. However, a terminal having a wider terminal as shown in FIG. 5 can be used more effectively. Further, the width of the pole (connection means between the terminal and the internal electrode) 7 is wider in the one shown in FIG. That is, in the example shown in FIG.
The thermal coupling between the electrode and the internal electrode plate or 6 is strengthened as compared with the example of FIG. Therefore, the thermal coupling between the heat sink 30 and the internal electrode 4 or 6 is also strengthened. More specifically, the pole 7 connecting the terminal 12 and the internal electrode 4 or 6
Is preferably widened to the extent that it extends over a majority of the internal electrodes 4 or 6 so as to be mechanically directly connected to the internal electrodes 4 or 6.

As described above, according to the present invention, the battery internal electrode is thermally coupled to the heat transfer means,
The battery temperature is controlled from the inside. Therefore,
For example, when used in combination with a conventional temperature control from the outside of the battery, the temperature of the battery can be controlled very effectively. Further, the present invention is particularly useful when a plurality of batteries are connected and used, and it is possible to eliminate temperature variations among the plurality of batteries and to make performance and life uniform.

[Brief description of the drawings]

FIG. 1 is an exploded perspective view of a preferred embodiment of the present invention.

FIG. 2 is a perspective view of a battery pack.

FIG. 3 is a perspective view showing a state where a battery is connected by a connector (a battery pack).

FIG. 4 is an exploded perspective view showing another embodiment according to the present invention.

FIG. 5 is a partially cutaway perspective view showing an example of a battery suitable for use in the present invention.

FIG. 6 is a partially broken perspective view of an example of a normal battery.

[Explanation of symbols]

 Reference Signs List 4 internal electrode 5 separator 6 internal electrode 7 pole (connection means between terminal and internal electrode) 8 battery assembly 10 battery 12 battery terminal 14 connector 16 first electrode connector 17 positive electrode of battery assembly 18 second electrode connector Reference Signs List 22 Insulating heat transfer means (insulation heat transfer sheet) 24 Conductive plate 26 One end 30 Heat transfer means (heat sink) 32 Screw 34 Holding plate 36 Holding plate 38 Screw 40 Rod 42 Heat transfer plate 44 Fin (Heat exchange means)

Claims (6)

[Claims] 1. Heat transfer means thermally coupled to a terminal of a battery, wherein the heat transfer means is thermally coupled to an internal electrode of the battery via the terminal, and heat exchange is performed at the heat transfer means. A battery temperature controller that controls the temperature of the battery. 2. The battery temperature control device according to claim 1, wherein said heat conducting means is thermally coupled to said internal electrode via an electrode connector connected to said terminal of said battery. 3. The heat conduction means is connected to the internal electrode by connecting the terminals of the plurality of batteries in series or parallel using a connection connector, and thermally connecting the connection connector to the heat conduction means. The battery temperature control device according to claim 1, wherein the battery temperature control device is thermally coupled to the battery temperature control device. 4. An insulating heat transfer means for electrically insulating the electrode connector or the connector from each other and thermally connecting the electrode connector or the connector to the heat conductive means. Item 4. The battery temperature control device according to item 2 or 3. 5. The battery temperature control device according to claim 4, wherein said insulating heat transfer means has a heating mechanism, and heats said battery as needed. 6. The battery temperature control device according to claim 1, further comprising heat exchange means for heating or cooling said heat conduction means.