KR20120013479A - Battery Module Containing Thermoelectric Film - Google Patents

Abstract

PURPOSE: A battery module is provided to restrain the size increasing of the whole battery module, by mounting thermoelectric film on one side of a battery cell for removing heat, and to easily control the optimum operation temperature of the battery module. CONSTITUTION: A battery module comprises one or more thermoelectric films on interface of each battery cell. The thermoelectric film comprises a thermoelectric element having a heat absorption plane and a heat radiation plane, and a conductive layer(220) for conducting the heat of thermoelectric element. The heat absorption plane of the thermoelectric plane is contacted to battery cells, and the heat radiation plane is contacted to the conductive layer.

Description

Battery module containing a thermoelectric film {Battery Module Containing Thermoelectric Film}

The present invention relates to a battery module including a thermoelectric film, and more particularly, a battery module in which plate-shaped battery cells are embedded in a pack case and sequentially stacked, wherein each of the battery cell interfaces includes a thermoelectric film interposed therebetween. The thermoelectric film includes a thermoelectric element having a surface capable of absorbing heat when energized and a surface exhibiting a heat generating function, and a conductive layer for conducting heat of the thermoelectric element, wherein the heat absorbing surface of the thermoelectric element is a battery cell. Face to face, the heat generating surface is directed to a battery module having a structure in contact with the conductive layer.

BACKGROUND ART [0002] In recent years, rechargeable secondary batteries have been widely used as energy sources for wireless mobile devices. In addition, the secondary battery is an electric vehicle (EV), a hybrid electric vehicle (HEV), a plug-in hybrid electric vehicle that has been proposed as a solution for air pollution of existing gasoline and diesel vehicles using fossil fuel. It is attracting attention as a power source such as (Plug-In HEV).

In a small mobile device, one or two or more battery cells are used per device, while a middle- or large-sized battery module such as an automobile is used as a middle- or large-sized battery module in which a plurality of battery cells are electrically connected due to the necessity of a large-

Since medium and large battery modules are preferably manufactured in a small size and weight as possible, square batteries and pouch-type batteries, which can be charged with high integration and have a small weight to capacity, are mainly used as battery cells (unit cells) of medium and large battery modules. have. In particular, a pouch-shaped battery using an aluminum laminate sheet or the like as an exterior member has recently attracted a lot of attention due to its advantages such as small weight, low manufacturing cost, and easy shape deformation.

Since the battery cells constituting the medium-large battery module are composed of secondary batteries capable of charging and discharging, such a high output large capacity secondary battery generates a large amount of heat during the charging and discharging process. In particular, the laminate sheet of the pouch-type battery widely used in the battery module is coated with a low thermal conductivity polymer material, it is difficult to effectively cool the temperature of the entire battery cell.

If the heat of the battery module generated during the charging and discharging process is not effectively removed, thermal accumulation occurs and consequently promotes deterioration of the battery module, and in some cases may cause fire or explosion. Therefore, a vehicle battery pack that is a high output large capacity battery requires a cooling system for cooling the battery cells embedded therein.

A battery module mounted in a medium-large battery pack is generally manufactured by stacking a plurality of battery cells with high density, and stacking adjacent battery cells at regular intervals to remove heat generated during charging and discharging. For example, the battery cells themselves may be sequentially stacked without a separate member at predetermined intervals, or in the case of battery cells having low mechanical rigidity, one or more combinations may be embedded in a cartridge or the like, and a plurality of such cartridges may be stacked. The battery module can be configured. A coolant flow path is formed between the battery cells or the battery modules so as to effectively remove heat accumulated between the stacked battery cells or the battery modules.

However, this structure has a problem in that the total size of the battery module is increased because a plurality of refrigerant passages must be secured corresponding to the plurality of battery cells.

In this regard, the present invention uses a thermoelectric element that generates a temperature difference between the two sides when the current is applied as described in detail later to prevent the rise of the temperature of the battery module and at the same time the battery to operate in the appropriate temperature range To provide.

As an example of using a thermoelectric element in a battery pack, Korean Patent Laid-Open Application No. 2005-0096786 discloses an air inlet and an outlet formed on one surface of a housing surrounding an outer surface of a battery pack, and a driving fan for the flow of air is provided. Located on the flow path, the air inlet discloses a technique in which a Peltier element for controlling the temperature of the air flowing in is installed.

However, the above technique is increasing the cooling efficiency of the battery by using the Peltier element, but the assembly process is complicated by installing the Peltier element in the position in consideration of the inlet and the outlet and installing a separate driving fan. It is complex and can be subject to design constraints.

Therefore, while providing a high output large capacity power can be manufactured in a simple and compact structure, there is a high need for a battery module excellent in life characteristics and safety.

SUMMARY OF THE INVENTION It is an object of the present invention to solve the above-described problems of the prior art and the technical problems required from the past.

An object of the present invention is to provide a battery module that can easily adjust the optimum operating temperature of the battery module while suppressing the increase in size of the entire battery module by removing the heat by mounting a thermoelectric element on one surface of the battery cell.

A battery module including a thermoelectric film according to the present invention for achieving the above object is a battery module in which a plurality of plate-shaped battery cells are built in a pack case and sequentially stacked,

Each battery cell interface is interposed with one or more thermoelectric film,

The thermoelectric film includes a thermoelectric element having a surface (heat absorbing surface) and a surface (heating surface) exhibiting heat generation capability when energizing, and a conductive layer for conducting heat of the thermoelectric element,

The heat absorbing surface of the thermoelectric element faces the battery cell, and the heat generating surface has a structure in contact with the conductive layer.

That is, when the battery cell mounted inside the battery module is overheated by various causes, the thermoelectric film absorbs heat through the heat absorbing surface in contact with the battery cell and radiates heat from the heat generating surface, thereby maintaining a safe temperature. Lower to the range. Therefore, since the thermoelectric element is installed at the inlet of the battery module and the battery cell stack can be cooled in a simpler and more compact structure than the conventional cooling system in which a separate driving fan is installed, the cooling efficiency of the battery module is maximized. It is possible to stack battery cells with high integration.

The thermoelectric film may be interposed in a direction in which the two thermoelectric films are opposed to each other, in order to achieve heat transfer at the interface of the battery cell more efficiently. In some cases, one thermoelectric film may be interposed between the battery cells or one conductive layer may include thermoelectric elements in directions facing each other.

The circuit for the operation of the thermoelectric element may be connected to the control unit for the operation of the battery module via the electrode member. That is, in the connection of the thermoelectric element and the control unit, the circuit may be configured to be connected or integrally connected to each thermoelectric element. Examples of the control unit may include a battery management system (BMS), but are not limited thereto.

The electrode member is not particularly limited as long as the electrode member is mounted on the battery cell so as to connect the thermoelectric element to the control unit when the battery module is configured. For example, the electrode member may be located at any one of the top, side, and bottom of the battery cells. It may be a structure.

The thermoelectric element may be formed on the conductive layer in various forms. In one example, the thermoelectric element may be formed on the entire surface of the conductive layer so as to be in contact with one surface of the battery cell.

In another example, in order to increase the efficiency of the endothermic and exothermic rate of the thermoelectric element when the current is applied, the thermoelectric element may be formed in the conductive layer in two or more independent island shapes. Accordingly, the endothermic and exothermic phenomenon can be induced more quickly on one surface of the battery cell in which the thermoelectric element is interposed.

In the above structure, the island-shaped thermoelectric elements may be preferably formed in a regular pattern so as to increase operating efficiency and cooling efficiency, and may be patterned in a honeycomb shape to induce more uniform cooling. It is not limited only to that.

In addition, the island-shaped thermoelectric elements are preferably interconnected in series and connected to the controller.

On the other hand, the thermoelectric element is a thermoelectric element that generates an endothermic or heat dissipation phenomenon at both ends when a current is applied, for example, may be a Peltier element.

In one preferred embodiment, the thermoelectric element is in contact with the conductive layer having a high thermal conductivity can perform effective heat dissipation to the outside of the battery module. Examples of the conductive layer include, but are not limited to, a metal layer made of any one of aluminum nitride (AlN), copper, silver, and stainless steel, a graphite layer, and the like.

In another preferred embodiment, in order to increase structural stability and handleability and mechanical rigidity in the assembly process of the battery module, the thermoelectric film may further include a film substrate on which the conductive layer is mounted. For example, it may be a polymer film. The raw material of such a polymer film is not specifically limited, For example, a polypropylene film, a polyester film, etc. are mentioned, A polymer resin excellent in heat resistance may be used depending on a case.

The conductive layer may be thermally fused to this film substrate or formed by vapor deposition.

The battery module according to the present invention includes a plurality of battery cells to achieve a high output large capacity, the high temperature generated during charging and discharging of the electric vehicle, a hybrid electric vehicle, or a plug-in hybrid electric vehicle seriously emerged in terms of safety It can be preferably used for a power source.

As described above, in the battery module including the thermoelectric film according to the present invention, a thermoelectric film for promoting heat dissipation of the battery is interposed at the battery cell interfaces, and the thermoelectric element is patterned on the conductive layer. While minimizing the increase in the size of the battery module it can effectively discharge the heat generated from the battery cell to the outside.

1 is a schematic view of a battery module according to an embodiment of the present invention;
FIG. 2 is a schematic side view of the thermoelectric film of FIG. 1; FIG.
3 is a plan view of a thermoelectric film and a control unit according to an embodiment of the present invention;
4 is a plan view of a thermoelectric film and a controller according to another embodiment of the present invention;
5 is a partial side view of a thermoelectric film including a film substrate.

Hereinafter, embodiments of the present invention will be described with reference to the accompanying drawings, but the present invention is not limited by the scope of the present invention.

1 is a schematic diagram of a battery module according to an embodiment of the present invention, Figure 2 is a schematic side view of the thermoelectric film of FIG.

Referring to these drawings, the battery module 300 includes a plurality of plate-shaped battery cells 100 are built in the pack case 310 and sequentially stacked, and each thermoelectric film 200 is interfaced to each battery cell 100 interface. Intervened.

The thermoelectric film 200 has a Peltier element 210 having a heat absorbing surface 211 that exhibits heat absorbing ability and a heat generating surface 212 that exhibits a heat generating function, and a conductive layer that conducts heat from the Peltier element 210. And 220.

The heat absorbing surface 211 of the Peltier element 210 faces the battery cell 100, and the heat generating surface 212 is in contact with the conductive layer 220.

The thermoelectric film 200 is interposed between the two thermoelectric films in a direction facing each other (A), or includes a Peltier element 210 in each of the conductive layers 220 in a direction facing each other (B). Alternatively, the thermoelectric film 200 may be formed in various ways such as interposing one thermoelectric film 200 at an interface of the battery cell 100.

The conductive layer 220 may be a metal layer or a graphite layer made of any one of aluminum nitride (AlN), copper, silver, and stainless steel.

3 is a plan view of a thermoelectric film and a controller according to an embodiment of the present invention.

Referring to FIG. 3 together with FIG. 1, the circuit 230 for the operation of the Peltier element 210a is provided for the operation of the battery module 300 via the electrode member 110 located at the side of the battery cell 100. The circuit 230 is connected in series to each of the Peltier elements 210a in the connection between the Peltier element 210a and the controller 320.

In addition, since the Peltier element 210a is formed in six independent island shapes in the conductive layer 220, the endothermic and heat generation phenomenon may be more rapidly generated on one surface of the battery cell in which the Peltier element 210a is interposed by the application of a current. Can be induced.

4 is a plan view of a thermoelectric film and a controller according to another exemplary embodiment of the present invention.

Referring to FIG. 4, the Peltier element 210b is the same as FIG. 3 except that the Peltier element 210b is patterned into an island-shaped honeycomb shape, and thus a detailed description thereof will be omitted.

FIG. 5 schematically shows a partial side view including a film substrate in the thermoelectric film of FIG. 3.

Referring to FIG. 5 together with FIG. 3, the thermoelectric film 200 ′ further includes a polymer film 240 on which the conductive layer 220 is mounted, thereby providing higher mechanical rigidity, structural stability, and handling property in the thermoelectric film. Can be given.

Those skilled in the art will appreciate that various modifications, additions and substitutions are possible, without departing from the scope and spirit of the invention as disclosed in the accompanying claims.

Claims (15)

A battery module in which a plurality of plate-shaped battery cells are built in a pack case and sequentially stacked,
Each battery cell interface is interposed with one or more thermoelectric film,
The thermoelectric film includes a thermoelectric element having a surface (heat absorbing surface) and a surface (heating surface) exhibiting heat generation capability when energizing, and a conductive layer for conducting heat of the thermoelectric element,
The heat absorbing surface of the thermoelectric element is facing the battery cell, the heat generating surface is in contact with the conductive layer, the battery module. The battery module of claim 1, wherein two thermoelectric films are interposed in the battery cell interface in a direction facing each other. The battery module according to claim 1, wherein the circuit for operating the thermoelectric element is connected to a control unit for operating the battery module via an electrode member. The medium-large battery pack of claim 3, wherein the electrode member is positioned at any one of an upper portion, a side portion, and a lower portion of the battery cells. The battery module according to claim 1, wherein the thermoelectric element is formed on the entire conductive layer. The battery module according to claim 1, wherein the thermoelectric element is formed in a conductive layer in two or more independent island shapes. The battery module according to claim 6, wherein the island-shaped thermoelectric elements are formed in a regular pattern. 8. The battery module according to claim 7, wherein the island-shaped thermoelectric elements are patterned in a honeycomb shape. 7. The battery module according to claim 6, wherein the island-shaped thermoelectric elements are interconnected in series. The battery module according to claim 1, wherein the thermoelectric element is a Peltier element. The method of claim 1, wherein the conductive layer is a battery module, characterized in that the metal layer or graphite (graphite) layer made of any one of aluminum nitride (AlN), copper, silver, stainless steel. The battery module of claim 1, wherein the thermoelectric film further comprises a film substrate on which a conductive layer is mounted. 13. The battery module according to claim 12, wherein the film substrate is a polymer film. The battery module of claim 12, wherein the film substrate is formed by being deposited on a conductive layer. The battery module according to claim 1, wherein the battery module is used as a power source for an electric vehicle, a hybrid electric vehicle, or a plug-in hybrid electric vehicle.

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