KR101501026B1 - Battery Module with Excellent Cooling Efficiency and Compact Structure - Google Patents

Abstract

The present invention relates to a battery cell laminate in which battery cells are stacked in a vertical direction; An upper plate and a lower plate surrounding the lower end face and the upper end face of the battery cell stack body; Cooling fins interposed at an interface of the battery cells and having ends protruding from one side or both sides of the battery cell stack; A heat transfer pad closely attached to a protruding end of the cooling fins; And a cooling member mounted on one side or both side surfaces of the battery cell laminate in a state of being closely contacted with the heat transfer pad and having a refrigerant flow path formed therein; And a battery module.

Description

[0001] The present invention relates to a battery module having excellent cooling efficiency and a compact structure,

The present invention relates to a battery module including a plurality of battery cells, and more particularly to a battery module including a battery cell stack in which battery cells are stacked in a vertical direction, an upper plate surrounding the lower end surface and the upper surface of the battery cell stack, A lower plate, a plurality of cooling fins interposed at the interface between the battery cells, the cooling fins protruding from one side or both sides of the battery cell stack body, a heat transfer pad closely attached to the projecting end of the cooling fins, And a cooling member which is mounted on one side or both side surfaces of the battery cell stack body in a state where the refrigerant flow path is formed.

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 (HEV), and the like, which are proposed as solutions for air pollution of existing gasoline vehicles and diesel vehicles using fossil fuels (Plug-In HEV) and the like.

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 the middle- or large-sized battery module is preferably manufactured in a small size and weight, a prismatic battery, a pouch-shaped battery, or the like, which can be charged with a high degree of integration and has a small weight to capacity, is mainly used as a battery cell 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 such a middle- or large-sized battery module are constituted by a rechargeable secondary battery, such a high-output large-capacity secondary battery generates a large amount of heat in the charging and discharging process. Particularly, since the laminate sheet of the pouch-type battery widely used for the battery module has a surface coated with a polymer material having low thermal conductivity, 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 can not be effectively removed, heat accumulation may occur, thereby accelerating the deterioration of the battery module and possibly causing ignition or explosion. Therefore, a cooling system for cooling the battery cells built in the high-power, large-capacity battery pack is required.

The battery module mounted on the middle- or large-sized battery pack is generally manufactured by stacking a plurality of battery cells at a high density, and adjacent battery cells are stacked at a predetermined interval so as to remove heat generated during charging and discharging. For example, the battery cells themselves may be sequentially stacked while being spaced apart from each other by a predetermined space, or in the case of a battery cell having low mechanical rigidity, one or a combination of two or more batteries may be built in a cartridge or the like. The battery module can be configured. The stacked battery cells or the battery modules are structured such that a flow path of the coolant is formed between the battery cells or the battery modules so as to effectively remove accumulated heat.

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

In addition, as the number of battery cells is increased, a number of components are added in relation to the cooling structure, thereby increasing the volume of the battery module, complicating the manufacturing process, and increasing the manufacturing cost.

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

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.

Specifically, an object of the present invention is to provide a battery module having a compact structure which can be effectively removed from a battery cell without using many members.

It is still another object of the present invention to provide a battery module which is excellent in safety while providing high power, large capacity power, and has excellent manufacturing processability.

According to an aspect of the present invention,

A battery cell laminate in which battery cells are stacked in a vertical direction;

An upper plate and a lower plate surrounding the lower end face and the upper end face of the battery cell stack body;

Cooling fins interposed at an interface of the battery cells and having ends protruding from one side or both sides of the battery cell stack;

A heat transfer pad closely attached to a protruding end of the cooling fins; And

A cooling member mounted on one side or both sides of the battery cell laminate in a state of being in tight contact with the heat transfer pad and having a refrigerant flow path formed therein;

As shown in FIG.

Generally, the battery module is constructed by stacking the battery cells so as to be spaced apart from each other by a predetermined distance in order to form a coolant passage, and the coolant such as air flows in the spaced spaces to prevent overheating of the battery cells. Further, a duct is formed on one side of the battery module so that the inlet and the outlet of the refrigerant are positioned and the flow of the refrigerant can be smoothly performed, and a cooling fan for the flow of the refrigerant is additionally installed if necessary.

In contrast, in the battery module of the present invention, the cooling fins are interposed between the battery cells, the ends of the cooling fins protrude to the side of the battery cell stack body, heat is transferred to the cooling member through the heat transfer pads, So that high cooling efficiency can be achieved without using many members.

Further, since the heat generated from the battery cells can be effectively removed to the outside without being based on the conventional cooling system, the assembly processability can be improved as a result, and a very compact battery module can be constructed.

The battery cell is preferably formed of a plate-shaped battery cell so as to provide a high deposition rate in a limited space. The plate-shaped battery cell has a structure in which anode and cathode terminals protrude from one side of the battery cell, The terminals may protrude from one side of the main body of the battery cell and the other electrode terminal may protrude from the opposite side.

Among them, a structure in which the electrode terminals are protruded to one side is more preferably used in order to connect the positive and negative terminals of the battery cells using a bus bar having a simple structure.

The plate-shaped battery cell may be, for example, a pouch-shaped battery cell having a structure in which an electrode assembly is embedded in a battery case of a laminate sheet including a resin layer and a metal layer.

Specifically, the plate-shaped battery cell is a pouch-shaped battery cell in which an electrode assembly having an anode, a separator, and a cathode structure is sealed inside a battery case together with an electrolytic solution, and is a plate-shaped battery cell having a generally rectangular parallelepiped structure . Such a pouch-shaped battery cell is generally composed of a battery case of a pouch type, and the battery case is composed of an outer coating layer made of a polymer resin having excellent durability; A barrier layer made of a metal material exhibiting barrier properties against moisture, air, and the like; And an inner sealant layer composed of a polymer resin that can be thermally fused, are laminated in this order.

The case of the pouch-type battery cell may have a variety of structures. For example, the case may be a two-unit member, which houses the electrode assembly in the housing portion formed on the upper and / or lower inner surface, And a structure for sealing by heat fusion. A pouch-shaped battery cell having such a structure is disclosed in PCT International Application No. PCT / KR2004 / 003312 of the present applicant, which application is incorporated herein by reference.

In one preferred example, the battery cells may be structured to be fixed to battery cartridges. That is, each of the battery cells may be fixed by a respective battery cartridge of a frame structure that fixes the outer circumferential surfaces thereof.

These battery cartridges are preferably pierced with a fastening hole through which the battery cells fixed by the battery cartridge are fastened to the upper plate and the lower plate by fastening members penetrating through the fastening holes and joined to the upper plate and the lower plate. The stacked structure can be fixed.

The cooling fin interposed at the interface of the battery cells is not particularly limited as long as it is a thin member having thermal conductivity. For example, a metal plate may be preferably used. As the metal material, aluminum or aluminum alloy having high thermal conductivity and light weight among metals may be preferably used, but it is not limited thereto.

In one preferred example, the end of the cooling fin may be bent vertically to enclose the end of the cartridge. In this case, when the battery cartridge to which the battery cells are fixed is stacked, the ends of the vertically bent cooling fins are aligned on a straight line in the up-down direction.

The cooling fins may be bent in a shape corresponding to the outer surfaces of the battery cell and the cartridge so as to be in close contact with the outer surface of the battery cell and the outer surface of the cartridge. That is, the cooling fin can be bent according to the outer surface structure of the battery cell so that the cooling fin can be closely attached to the battery cell corresponding to the outer surface structure of the battery cell. Further, the cooling fins may be bent in a shape corresponding to the outer surface of the cartridge fixing the outer circumferential surface of the battery cell. For example, the cooling fin may be in close contact with the battery cell, And may be formed by bending along the outer surface and coming into close contact with each other.

The cooling fin may include a first cooling fin contacting the upper surface of the battery cell with respect to the battery cell, and a second cooling fin contacting the lower surface of the battery cell. The first cooling fin and the second cooling fin may have symmetrical structures depending on the shape of the battery cell.

The cartridge may preferably have a structure in which a step is formed in the direction of one side end so that the cooling member is received in a plane and fixed in place.

The heat transfer pad is a member that is positioned between the end of the cooling fin and the cooling member and efficiently transmits the heat of the cooling fin to the cooling member. In order to improve the adhesion between the end of the cooling fin and the cooling member, Lt; / RTI > As one example, the heat transfer pad may be manufactured by combining a thermally conductive material with silicon so that elasticity and thermal conductivity can be simultaneously exhibited.

The cooling member may be air-cooling or water-cooling member, and air or cooling water may flow through the refrigerant passage. Preferably, the cooling water flows in the refrigerant passage, and the cooling water is cooled by the cooling water flowing in the refrigerant passage of the cooling member through the cooling fin.

As described above, in the battery cell, the positive electrode and the negative electrode terminals protrude from one side of the main body of the battery cell, or one electrode terminal protrudes from one side of the main body of the battery cell, As shown in FIG. In particular, a battery cell having a structure in which positive and negative terminals are protruded from one side of a battery cell body may be preferably used, and a bus bar assembly for electrically connecting the electrode terminals of the battery cells may be formed on one side of the battery cell stack body As shown in FIG.

In addition, an electrically insulating bus bar cover may be further included to allow the electrical connection portion of the bus bar assembly to be insulated from the outside.

In one preferred embodiment, the battery module includes means for detecting temperature and voltage in order to prevent overheating, malfunction, and the like, and to improve safety. Temperature information and voltage information measured by these means are transmitted to a separate controller do. A temperature connector and a voltage connector may be mounted on an opposite surface of the bus bar cover on which the bus bar assembly is located. The temperature connector and the voltage connector and the control unit are electrically connected by a wire. The control unit may be, for example, a battery management system (BMS), which is a battery management system.

Further, a wire cover for insulating and protecting a member such as a temperature connector, a voltage connector, and a wire located on the outer surface of the bus bar cover from the outside may be further included.

The present invention also provides a battery pack including the battery module as a unit module.

The battery pack may be manufactured by assembling the battery module as a unit module according to a desired output and capacity. In consideration of mounting efficiency and structural stability, an electric vehicle, a hybrid electric vehicle, a plug-in hybrid electric vehicle, A storage device, etc., but the scope of application is not limited thereto.

Accordingly, the present invention provides a device comprising the battery pack as a power source, and the device can be specifically an electric vehicle, a hybrid electric vehicle, a plug-in hybrid electric vehicle or a power storage device.

The structure and manufacturing method of such a device are well known in the art, so a detailed description thereof will be omitted herein.

As described above, in the battery module according to the present invention, the cooling fins are interposed between the battery cells, the ends of the cooling fins protrude to the side of the battery cell stack body, heat is transferred to the cooling member through the heat transfer pads, So that high cooling efficiency can be achieved without using many members.

Further, since the heat generated from the battery cells can be effectively removed to the outside without being based on the conventional cooling system, the assembly processability can be improved as a result, and a very compact battery module can be constructed.

1 is a perspective view of a battery cell mounted on a battery module;
Figure 2 is an exploded perspective view of Figure 1;
3 is a perspective view of a battery module according to one embodiment of the present invention;
Figure 4 is an exploded perspective view of Figure 3;
Figure 5 is a plan view of Figure 3;
6 is a cross-sectional view showing the AA region of FIG. 5;
7 is a cross-sectional view showing the BB region of FIG. 5;
8 is an enlarged view of a portion C in Fig.

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.

FIG. 1 is a perspective view of an exemplary battery cell mounted on a battery module of the present invention, and FIG. 2 is a schematic exploded perspective view of FIG.

Referring to these figures, the pouch-shaped battery cell 100 includes an electrode assembly 120 including an anode, a cathode, and a separator disposed between the anode and the cathode, And two electrode terminals 132 and 134 electrically connected to the electrodes 122 and 124 are sealed so as to be exposed to one side.

The battery case 110 includes an upper case 114 and a lower case 116 including a concave shaped storage portion 112 into which the electrode assembly 120 can be seated.

The electrode assembly 120 having the folding, stacking or stacking / folding type structure has a structure in which a plurality of anode tabs 122 and a plurality of anode tabs 124 are welded together and joined together to the electrode terminals 132 and 134 have. When the outer circumferential surfaces of the upper case 114 and the lower case 116 are thermally fused with each other, a short circuit is prevented from occurring between the heat fusers and the electrode terminals 132 and 134, The insulating film 140 is attached to the upper and lower surfaces of the electrode terminals 132 and 134 in order to ensure the sealing property between the battery case 110 and the battery case 110.

The upper case 114 and the lower case 116 are composed of an outer resin layer 117, a barrier metal layer 118 and an inner resin layer 119. The inner resin layer 119 is composed of a heat fusion machine So that it can be tightly fixed.

When the electrode assembly 120 impregnated with the electrolytic solution is mounted on the housing part 112 and the outer circumferential surface contact portions of the upper case 114 and the lower case 116 are thermally fused, a sealing part is formed.

FIG. 3 is a perspective view of a battery module according to an embodiment of the present invention, and FIG. 4 is an exploded perspective view of FIG.

Referring to these drawings, the battery module 200 includes a battery cell stack 400 in which a plurality of structures in which the battery cells 410 are mounted on the cartridges 430 are stacked one above the other, The upper plate 310 and the lower plate 320 surrounding the lower end surface and the upper end surface of the battery cell stack body 400 and the side plates of the battery cell stack body 400 mounted on both side surfaces of the battery cell stack body 400 And a cooling member (600).

The cooling fin 420 is made of a metal plate having a high thermal conductivity and is closely attached to the battery cell 410 so that heat generated in the battery cell 410 is conducted, (600).

The battery cartridge 430 has a structure for fixing the outer circumferential surfaces of the respective battery cells 410. A cooling member 600 is received in a plane and a step 432 is formed in one end direction Respectively.

The bus bar assembly 700 is mounted on one end of the battery cell stack 400. The protruded anode and cathode terminals of the battery cells 410 are electrically connected to the bus bar assembly 700 by the bus bar assembly 700 . An electrical insulating bus bar cover 800 is mounted on the outside of the bus bar assembly 700 so that the electrical connection portion of the bus bar assembly 700 is insulated from the outside.

A temperature connector 810 and a voltage connector 820 are mounted on the opposite surface of the bus bar cover 800 where the bus bar assembly 700 is located. Accordingly, the temperature connector 810 and the voltage connector 820 are structured to be connected to a separate control section, for example, by a wire or the like.

The bus bar cover 800 has a structure in which a wire cover 900 for inserting a temperature connector 810, a voltage connector 820, and wires connected to the temperature connector 810 from the outside is mounted on the outside of the bus bar cover 800.

Fig. 5 is a plan view of Fig. 3, Fig. 6 is a sectional view taken along the line A-A of Fig. 5, and Fig. 7 is a sectional view taken along the line B-B of Fig.

Referring to these figures, the battery cells 410 are stacked and the outer peripheral surface of each of the battery cells 410 is fixed by the battery cartridge 430. Fastening members are formed at corners of the battery cartridge 430 so that the battery cells 410 are inserted into the cartridge 430 through the fastening holes and are fastened to the upper plate 310 and the lower plate 320. [ (Electronic cell stack) 400 is fixed between the upper plate 310 and the lower plate 320. As shown in FIG.

Fig. 8 schematically shows a structure in which the C region in Fig. 7 is enlarged.

Referring to FIG. 8 together with FIG. 7, the outer circumferential surface of the battery cell 410 is pressed by the cartridge 430 to fix the battery cell 410 to the cartridge 430. A cooling fin 420 is positioned between the cartridge 430 and the battery cell 410 and is bent in a shape corresponding to the outer surface of the battery cell 410 and the cartridge 430, (A) so as to surround the end portion of the first spring 430. Accordingly, when the cartridge 430 in which the battery cells 410 are fixed is stacked, the ends of the vertically bent cooling fins 420 are aligned on a straight line in the vertical direction.

The cooling fin 420 is divided into a first cooling fin 422 contacting the upper surface of the battery cell 410 and a second cooling fin 424 contacting the lower surface of the battery cell 410, As shown in FIG.

The heat transfer pad 500 is a member that is positioned between the end of the cooling fins 422 and 424 and the cooling member 600 to efficiently transmit the heat of the cooling fins 422 and 424 to the cooling member 600, And is made of a material having elasticity and restoring force to improve the adhesion between the end portions of the pins 422 and 424 and the cooling member 600. Therefore, when the cooling member 600 is mounted on the side surface of the battery cell stack 400, the cooling member 600 presses the side surface of the battery cell stack 400 through the heat transfer pad 500, And has a structure that improves the structural stability and thermal conductivity of the battery cell stack body 400.

In the cooling member 600, a coolant channel 610 is formed, and the coolant flows through the coolant channel 610 to perform cooling. That is, the heat generated in the battery cell 410 is conducted to the cooling member 600 through the cooling fin 420 and the temperature of the battery module 200 is reduced by indirectly cooling the cooling member 600 It is composed of structure to control.

While the present invention has been described with reference to exemplary embodiments, it is to be understood that the invention is not limited to the disclosed exemplary embodiments.

Claims (21)

A battery cell laminate in which battery cells are stacked in a vertical direction;
A battery cartridge having a frame structure for fixing an outer circumferential surface of the battery cells, the battery cartridge comprising:
An upper plate and a lower plate surrounding the lower end face and the upper end face of the battery cell stack body;
A first cooling fin interposed at an interface of the battery cells and having an end protruding from one side or both sides of the battery cell stack body and contacting an upper surface of the battery cell with respect to the battery cell, 2 cooling fins including cooling fins;
The end of the cooling fin is bent in a shape corresponding to the outer surface of the battery cell and the cartridge so as to be in close contact with the outer surface of the battery cell and the outer surface of the cartridge,
A heat transfer pad closely attached to a protruding end of the cooling fins; And
A cooling member mounted on one side or both sides of the battery cell laminate in a state of being in tight contact with the heat transfer pad and having a refrigerant flow path formed therein;
The battery module comprising: The battery module according to claim 1, wherein the battery cells are plate-shaped battery cells having electrode terminals formed on one side or both sides thereof. The battery module according to claim 2, wherein the plate-shaped battery cell is a pouch-shaped battery cell manufactured by embedding an electrode assembly in a case of a laminate sheet including a resin layer and a metal layer, and sealing an outer circumferential surface of the case. The battery module according to claim 2, wherein the plate-shaped battery cell has a structure in which a positive terminal and a negative terminal are formed on one side. The battery module according to claim 1, wherein the cooling fin is made of a metal plate having thermal conductivity. The battery module according to claim 5, wherein the cooling fin is made of aluminum or an aluminum alloy. delete The battery module according to claim 1, wherein each of the battery cartridges further includes a fastening member having a fastening hole formed therein, the fastening member passing through the fastening hole and being coupled to the upper plate and the lower plate. delete delete delete delete The battery module according to claim 1, wherein the heat transfer pad is made of an elastic material. The battery module according to claim 1, wherein the coolant member is a water-cooled member, and the coolant flows through the coolant channel. 2. The battery pack according to claim 1, wherein the battery cells have a structure in which a positive terminal and a negative terminal are formed at one end of the battery cell, Wherein the battery module further comprises a bus bar assembly. The battery module according to claim 15, further comprising an electrically insulating bus bar cover mounted on the bus bar assembly. 17. The battery module according to claim 16, wherein a temperature connector and a voltage connector are mounted on the opposite side of the side where the bus bar assembly is located on the bus bar cover. 17. The battery module according to claim 16, wherein a wire cover is further attached to the outer surface of the bus bar cover. A battery pack comprising the battery module according to any one of claims 1 to 6, 8 and 13 to 18 as a unit module. A device, comprising a battery pack according to claim 19. 21. The device of claim 20, wherein the device is an electric vehicle, a hybrid electric vehicle, a plug-in hybrid electric vehicle, or a power storage device.

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