KR101560217B1 - Battery Module of Improved Cooling Efficiency - Google Patents

Abstract

The present invention relates to a battery cell in which an electrode assembly including an anode, a cathode and a separator is housed in a battery case, a cathode lead and a cathode lead connected to the electrode assembly are protruded to the outside of the battery case, A cooling member mounted on at least one side of the battery cell stack, which is a stacked structure of the battery cells, and a cooling member interposed between the battery cell stack structure and the cooling member, And an electrically insulating thermally conductive member which is in contact with an end of at least one of the electrode leads of the positive electrode lead and the negative electrode lead of the battery module.

Description

[0001] The present invention relates to a battery module having improved cooling efficiency,

The present invention relates to a battery module having improved cooling efficiency, and more particularly, to a battery module having an electrode assembly including an anode, a cathode and a separator housed in a battery case, and a cathode lead and a cathode lead connected to the electrode assembly, A plurality of battery cells each having a structure protruding to the outside, a plurality of cartridges each having the battery cells fixed thereto to form a battery cell laminate structure, a cooling member mounted on at least one side of the battery cell laminate, And an electrically insulating heat conduction member interposed between the battery cell laminated structure and the cooling member and contacting an end of at least one electrode lead of the positive electrode lead and the negative electrode lead of the battery cells.

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.

2. Description of the Related Art [0002] In a middle- or large-sized device such as an automobile, a middle- or large-sized battery module in which a plurality of battery cells are electrically connected is used due to the necessity of a high output large capacity.

Since such a middle- or large-sized battery module is preferably manufactured with 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, . 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 a laminate sheet of a pouch-type battery widely used for a high output large-capacity battery module is coated with a polymer material having a 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 stacks adjacent battery cells spaced apart at regular intervals 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 a 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-mentioned problems of the prior art and the technical problems required from the past.

Specifically, it is an object of the present invention to provide a battery module which can reduce the temperature deviation of the battery cell and improve the cooling efficiency in spite of a compact structure without using many members.

According to an aspect of the present invention,

A battery cell in which an electrode assembly including an anode, a cathode, and a separator is housed in a battery case, a cathode lead and a cathode lead connected to the electrode assembly are protruded to the outside of the battery case;

Cartridges for fixing the battery cells to form a battery cell stack structure;

A cooling member mounted on at least one surface of the battery cell stack body which is a stacked structure of the battery cells; And

An electrically insulating heat conduction member interposed between the battery cell laminate structure and the cooling member and contacting an end of at least one electrode lead of the positive electrode lead and the negative electrode lead of the battery cells;

As shown in FIG.

Generally, when the internal temperature of the battery cell rises, the temperature of the electrode lead connected to the electrode assembly inside the battery case is exposed to the outside of the battery case, The cooling structure does not include a structure for directly cooling the electrode leads, so that there is a disadvantage that the temperature fluctuation of the battery cells rises and the cooling efficiency becomes poor.

However, since the battery module according to the present invention includes a structure in which the electrode lead portion whose temperature rises particularly high during the heat generation of the battery cell is cooled by the cooling member through the electrically insulating heat conduction member, And improves cooling efficiency to improve safety against ignition or explosion.

In one specific example, the battery cell is preferably formed of a plate-shaped battery cell so as to provide a high lamination ratio in a limited space, and is stacked so that one surface or both surfaces of the battery cell faces to adjacent battery cells to form a battery cell stack body . ≪ / RTI > Such a plate-shaped battery cell has a structure in which positive and negative terminals are protruded to one side of the battery cell, or one electrode terminal protrudes to one side of the main body of the battery cell, and the other electrode terminal is opposite to or adjacent to the side As shown in Fig.

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 . The pouch-type battery cell is generally composed of a pouch-type battery case, and the battery case includes an outer covering layer made of a polymer resin having excellent durability, a barrier layer made of a metal material exhibiting barrier properties against moisture, air, And an inner sealant layer made of a polymer resin that can be fused.

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.

The pouch-shaped battery cells are stacked in a state of being fixed by a cartridge. Specifically, the pouch-shaped battery cells are fixed to the cartridge by interposing the heat-sealed outer circumferential sealing portions of the pouch- Can be achieved.

The end of the electrode lead of the battery cell may be bent to be in close contact with the outer surface of the cartridge. Specifically, the end of the electrode lead protruding outward of the cartridge can be bent at an angle of about 90 degrees and can be brought into close contact with the outer surface of the cartridge. This structure increases the contact area with the electrically insulating heat conduction member to increase the heat conduction efficiency and further improve the cooling effect.

In one specific example, the battery module may further include a cooling fin. In a specific example of the structure of the cooling fin, one side of the cooling fin is interposed between the battery cells, The portion may be formed in a structure in which it is interposed between the electrically insulating heat conduction member and the cooling member in a bent state through the electrically insulating heat conduction member.

In this case, in order to prevent a short circuit that may occur when the electrode lead is in contact with the electrode lead, the bent portion may be positioned between the electrically insulating heat conduction member and the cooling member. That is, the end of the electrode lead is in close contact with the outer surface of the cartridge and is positioned between the cartridge and the electrically insulating heat conduction member, and the end of the cooling fin is located between the electrically insulating heat conduction member and the cooling member, And may be made of a structure that is insulated without being in contact with the insulating heat conduction member.

The structure of the cooling fin is not particularly limited as long as it is a thin member having thermal conductivity. For example, a sheet of a metal material can be preferably used. The metal material may be aluminum or aluminum alloy having high thermal conductivity and light weight among metals, but is not limited thereto.

The electrically insulating thermally conductive member is a member that is positioned between the battery cell laminate structure and the cooling member and efficiently transfers heat of the battery cell laminate structure and the end portion of the electrode lead to the cooling member, And may be made of an elastic material to improve the adhesion between the cooling members. 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.

If the cooling member is a thermally conductive member, its material is not particularly limited, and for example, a metal material may be preferably used. The metal material may be aluminum or aluminum alloy having high thermal conductivity and light weight among metals, but is not limited thereto.

The cooling member may be an air-cooling or water-cooling member having a structure maximizing a contact surface with outside air, or a structure in which a coolant channel through which cooling water flows is formed.

The battery cell may be a secondary battery capable of providing a high voltage and a high current when the battery module and the battery pack are constructed. For example, the battery cell may be a lithium secondary battery having a large energy storage amount per volume.

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, the battery module according to the present invention includes a structure in which the electrode lead portion, in which the temperature particularly increases during the heat generation of the battery cell, is cooled by the cooling member through the electrically insulating heat conduction member, The temperature deviation of the battery cell is lowered and the cooling efficiency is improved, thereby improving the safety against ignition or explosion.

1 is a perspective view of one exemplary battery cell mounted in a battery module;
2 is an exploded perspective view of a battery module according to one embodiment of the present invention;
FIG. 3 is a schematic view showing a region where cooling is performed in a structure in which constituent elements of the battery module of FIG. 2 are combined;
4 is an exploded perspective view of a battery module according to another embodiment of the present invention;
FIG. 5 is a schematic view showing a region where cooling is performed in a structure in which constituent elements of the battery module of FIG. 4 are combined.

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.

For convenience of explanation, a housing, a cable, a protection circuit member, and the like included in the battery module are omitted in this specification.

1 is a perspective view of an exemplary battery cell mounted on a battery module of the present invention.

1, a pouch-shaped battery cell 110 is electrically connected to an electrode assembly (not shown) formed of a positive electrode, a negative electrode, and a separator disposed therebetween in a pouch-shaped battery case 112 And the two electrode terminals 114 and 116 are sealed so as to be exposed to the outside.

The battery case 112 is composed of an upper case and a lower case including a concave shaped receiving portion into which the electrode assembly can be seated.

A sealing portion is formed by thermally fusing the outer circumferential surface contact portion 113 of the upper case and the lower case in a state in which the electrode assembly impregnated with the electrolyte is seated in the storage portion 118. The sealing portion is vertically bent and closely attached to the side wall of the storage portion.

FIG. 2 is an exploded perspective view of a battery module according to an embodiment of the present invention, and FIG. 3 is a schematic view illustrating a region where cooling is performed in a structure in which components of the battery module of FIG. 2 are combined .

2 and 3, the battery module 100 includes pouch-shaped battery cells 110 and 110 ', cartridges 120 and 120', a cooling member 140, and an electrically insulating heat conduction member 130, As shown in FIG.

The positive electrode leads 114 and the negative electrode leads 116 connected to the electrode assembly are housed in the battery case 112. The battery cells 110 and 110 ' And the cartridges 120 and 120 'fix the battery cells 110 and 110', respectively, to form a stacked structure of the battery cells 110 and 110 '.

The cooling member 140 is mounted on one side of the laminate of the battery cells 110 and 110 'to conduct the cooling by conducting the heat of the battery cells 110 and 110', and the electric insulating heat conductive member 130, Is interposed between the stacking structure 110 and the cooling member 140 and is in contact with the end portion 115 of the electrode lead of the battery cells 110 and 110 '.

The ends 115 of the electrode leads protruding from the battery cells 110 and 110 'are bent at an angle of 90 degrees so as to be in close contact with the outer surfaces of the cartridges 120 and 120', so that contact with the electrically insulating heat conductive member 130 Increase the area to improve thermal conduction efficiency. The end portions 115 of the electrode leads are formed so that the end portions 115 of the electrode leads of the battery cells 110 and 110 'are bent to prevent contact between the electrode leads of adjacent battery cells 110 and 110' Direction and are symmetrical with each other.

The electrically insulating thermally conductive member 130 is a member having elasticity that allows the heat of the laminate structure of the battery cells 110 and 110 'and the end portion 115 of the electrode lead to be efficiently transferred to the cooling member 140, And a thermally conductive material is combined with silicone to improve the adhesion between the electrode leads 114 and 116 and the cooling member 140. In addition,

In addition, the cooling member 140 may include an air-cooling structure in which a contact surface with the outside air is maximized, or a water-cooling type cooling structure in which cooling water flows, and the cooling structure is not limited thereto Various cooling structures may of course be used.

FIG. 4 is an exploded perspective view of a battery module according to another embodiment of the present invention, and FIG. 5 is a schematic view showing a portion where cooling is performed in a structure in which components of the battery module of FIG. 4 are combined.

In FIGS. 4 and 5, other structures are the same, except that cooling pins 150 and 150 'are added to the structures shown in FIGS. 2 and 3, and a duplicate description will be omitted.

4 and 5, cooling pins 150 and 150 'are mounted between the electrically insulating heat conduction member 130 and the cooling member 140 to further improve the cooling efficiency of the battery module, One side of the cooling fins 150 and 150 'is interposed between the battery cells 110 and 110' and the remaining portions of the cooling fins 150 and 150 'are in a state in which the electrically insulating heat conductive member 130 is interposed And extends in a bent state so as to face the end portion 115 of the electrode lead.

The bent portion 155 is located between the electrically insulating thermally conductive member 130 and the cooling member 140 to prevent a short circuit that may occur when the electrode lead is in contact with the electrode lead. That is, the end portions 115 of the electrode leads are in close contact with the outer surfaces of the cartridges 120 and 120 'and are positioned between the cartridges 120 and 120' and the electrically insulating heat conduction member 130. The cooling fins 150 and 150 ' The bent end portions 155 are located between the electrically insulating thermally conductive member 130 and the cooling member 140 so that their ends are not contacted by the electrically insulating thermally conductive member 130 and are insulated Structure.

It will be understood by those of ordinary skill in the art that various changes in form and details may be made therein without departing from the spirit and scope of the invention as defined by the appended claims.

Claims (17)

A battery cell in which an electrode assembly including an anode, a cathode, and a separator is housed in a battery case, a cathode lead and a cathode lead connected to the electrode assembly are protruded to the outside of the battery case;
Cartridges for fixing the battery cells to form a battery cell stack structure;
A cooling member mounted on at least one surface of the battery cell stack body which is a stacked structure of the battery cells; And
An electrically insulating heat conduction member interposed between the battery cell laminate structure and the cooling member and contacting an end of at least one electrode lead of the positive electrode lead and the negative electrode lead of the battery cells;
The battery module comprising: The battery module according to claim 1, wherein the battery cell is a plate-shaped battery cell, and the battery cell stack is formed by stacking the battery cells so that one surface or both surfaces of the battery cell faces the adjacent battery cells. The pouch-shaped battery cell according to claim 2, wherein the plate-shaped battery cell is a pouch-shaped battery cell having a structure in which an outer periphery of a cell case is thermally fused and sealed with an electrode assembly embedded in a cell case of a laminate sheet including a resin layer and a metal layer . The battery module according to claim 3, wherein the outer circumferential surface of the pouch-shaped battery cell is thermally fused and fixed between the cartridges. The battery module according to claim 1, wherein an end of the electrode lead of the battery cell is bent to be in close contact with an outer surface of the cartridge. The battery module according to claim 1, wherein the battery module further includes a cooling fin, wherein one side of the cooling fin is interposed between the battery cells and the remaining portion of the cooling fin passes through the electric insulating heat conductive member, And the cooling member is interposed between the member and the cooling member in a bent state. delete The battery module according to claim 6, wherein the cooling fin is a sheet of a metal material. The battery module according to claim 8, wherein the metal material is aluminum or an aluminum alloy. The battery module according to claim 1, wherein the electrically insulating thermally conductive member is formed of a combination of a thermal conductive material and an elastic base material. The battery module according to claim 1, wherein the battery cell has a positive electrode and a negative electrode protruded on one side of an outer circumferential surface, or a positive electrode terminal protruded on one side of an outer circumferential surface, and a negative electrode terminal protruded on an opposite side opposite the battery cell. . The battery module according to claim 1, wherein the cooling member is formed of a metal material The battery module according to claim 1, wherein a coolant passage through which the coolant flows is formed in the cooling member. The battery module according to claim 1, wherein the battery cell is a lithium secondary battery. A battery pack comprising a battery module according to any one of claims 1 to 6 and 8 to 14 as a unit module. A device according to claim 15, comprising a battery pack. 17. The device of claim 16, 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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