KR20170014924A - Battery Module of Indirect Cooling - Google Patents

Abstract

According to an embodiment of the present invention, a battery module comprises: a large number of cell assemblies which include a battery cell and a laminated cartridge to support the battery cell, are arranged by lamination in the horizontal or the vertical direction; an annular type of a heat sink which is located on one side of a number of the cell assemblies, and has a flow path where a refrigerant flows therein; a large number of cooling plates wherein some of the cooling plates are interposed between the cell assemblies and the others are arranged on the flow path of the heat sink to absorb the heat from the cell assemblies; and second cooling plates which are arranged on the flow path of the heat sink, and connected to a number of the first cooling plates to absorb the heat from a number of the first cooling plates and to radiate the heat to the flow path.

Description

Indirect cooling type battery module {Battery Module of Indirect Cooling}

BACKGROUND OF THE INVENTION 1. Field of the Invention [0001] The present invention relates to a battery module, and more particularly, to a battery module that is excellent in cooling performance and is simple in structure and compact than the conventional battery module.

Secondary batteries having high electrical characteristics such as high energy density and high ease of application according to the product group can be applied not only to portable devices but also to electric vehicles (EVs) or hybrid electric vehicles (HEVs) driven by electric driving sources, Storage devices (Energy Storage System) and so on. Such a secondary battery is not only a primary advantage that the use of fossil fuel can be drastically reduced, but also produces no by-products resulting from the use of energy, and thus is attracting attention as a new energy source for enhancing environmental friendliness and energy efficiency.

The battery pack applied to the electric vehicle has a structure in which a plurality of cell assemblies including a plurality of unit cells are connected in series in order to obtain high output. The unit cell includes a positive electrode and a negative electrode current collector, a separator, an active material, an electrolyte, and the like, and can be repeatedly charged and discharged by an electrochemical reaction between the components.

In recent years, as a need for a large-capacity structure including an application as an energy storage source has increased, a demand for a multi-module battery pack in which a plurality of secondary batteries are connected in series and / or in parallel is assembled .

Since the battery pack of the multi-module structure is manufactured in such a manner that a plurality of secondary batteries are densely packed in a narrow space, it is important to easily discharge heat generated from each secondary battery. Since the process of charging or discharging the secondary battery is performed by the electrochemical reaction as described above, if the heat of the battery module generated in the charging and discharging process can not be effectively removed, heat accumulation occurs and consequently deterioration of the battery module is promoted , In some cases ignition or explosion may occur.

Therefore, a battery pack having a high output capacity and a battery pack to which the battery module is mounted is necessarily provided with a cooling device for cooling battery cells built therein.

Generally, there are two types of cooling devices, air cooling type and water cooling type. Air cooling type is more widely used than water cooling type due to leakage current or waterproofing of secondary battery.

1 is a perspective view schematically showing a structure of a cell assembly laminate 1 of a battery module to which a conventional air cooling method is applied.

Referring to FIG. 1, a conventional cell assembly includes a battery cell 2 and a stacking cartridge 3 for housing a battery cell. The stacking cartridge 3 includes a rectangular frame and an upper cooling plate (not shown) and a lower cooling plate (not shown). The frame has openings (4) formed through the side portions, and the upper and lower cooling plates are mounted at the upper and lower ends of the frame so as to be spaced apart from each other by a predetermined interval, A channel (not shown) may be formed. The battery cells 2 are arranged one by one so as to be in contact with the upper surface of the upper cooling plate and the lower surface of the lower cooling plate, and can be indirectly contacted with the air in the cooling channel and cooled.

However, such an indirect air-cooled battery module is disadvantageous in that the entire module size is increased as the cooling channels are provided between the battery cells 2. The space occupied by the battery cells 2 per unit volume is reduced due to the cooling channels of these battery modules, so that the energy density per unit volume is also lowered. In addition, the structure of the stacking cartridge 3 is complicated for designing the air flow path, and furthermore, the cooling plate made of an aluminum material tends to be deformed, so that there is a problem that the internal air flow passage is not stably secured.

Accordingly, it is an object of the present invention to provide an indirect cooling type battery module that is compact and has high energy density and excellent battery cell cooling performance.

Other objects and advantages of the present invention will become apparent from the following description, and it will be understood by those skilled in the art that the present invention is not limited thereto. It will also be readily apparent that the objects and advantages of the invention may be realized and attained by means of the instrumentalities and combinations particularly pointed out in the appended claims.

According to an aspect of the present invention, there is provided a battery pack comprising: a plurality of cell assemblies each having a battery cell and a stacking cartridge for supporting the battery cell, the cell assembly being stacked in a horizontal or vertical direction; A heat sink having a hollow structure and disposed at one side of the plurality of cell assemblies, and having a flow passage for flowing refrigerant therein; A plurality of first cooling plates interposed between the cell assemblies, the remainder being disposed in the flow path of the heat sink to absorb heat from the cell assemblies; And a second cooling plate disposed on the flow path of the heat sink and connected to the plurality of first cooling plates to absorb heat from the plurality of first cooling plates to dissipate heat on the flow paths, Can be provided.

According to another aspect of the present invention, the first cooling plate may include at least one through hole for passing the refrigerant.

According to another aspect of the present invention, the second cooling plate is provided in a plate shape, and the plate surface may be arranged horizontally with respect to the flow direction of the coolant.

According to another aspect of the present invention, a plurality of the second cooling plates may be provided, and the plurality of second cooling plates may be arranged in layers at regular intervals.

According to another aspect of the present invention, a portion of the first cooling plate, which is disposed in the flow path of the heat sink, is provided in a lattice form with a grating structure, and is perpendicular to the plurality of second cooling plates .

According to another aspect of the present invention, the heat sink includes: a heat sink lower plate mounted on one side of the cell assembly and having a plurality of slots such that the plurality of first cooling plates pass through the body; And a heat sink upper plate coupled to the heat sink lower plate to form a flow path therein.

According to another aspect of the present invention, there is provided a battery pack comprising: a first frame and a second frame which are assembled to each other with at least one battery cell therebetween and at least one side of the battery cell is exposed to the outside, Two frames may be included.

According to another aspect of the present invention, the first cooling plate and the second cooling plate may be integrally formed.

According to another aspect of the present invention, the plurality of first cooling plates may be arranged in a lateral direction with respect to a flow direction of the refrigerant.

According to another aspect of the present invention, a battery pack including the above-described battery module may be provided.

According to another aspect of the present invention, an automobile including the above-described battery module can be provided. The automobile may include an electric vehicle, a hybrid electric vehicle, a plug-in hybrid electric vehicle, and the like.

According to an aspect of the present invention, a module structure is simpler than the conventional one by interposing a part of the first cooling plate between the cell assemblies and air-cooling the remaining part of the first cooling plate outside the cell assembly, have.

According to another aspect of the present invention, a part of the first cooling plate and the second cooling plate are provided in the heat sink, so that the cooling efficiency can be improved by increasing the heat transfer rate and increasing the heat transfer area.

According to another aspect of the present invention, the first cooling plate includes the through holes to promote turbulent flow on the flow path inside the heat sink, and the pressure loss of the cooling fan can be reduced.

1 is a perspective view schematically showing a structure of a cell assembly laminate of a battery module to which an air cooling system according to the conventional art is applied.
2 is a perspective view schematically showing a configuration of a battery module according to an embodiment of the present invention.
3 is a cross-sectional view along the XZ-axis of Fig. 2. Fig.
4 is a perspective view schematically showing a configuration of a cell assembly according to an embodiment of the present invention.
5 is an exploded perspective view of the heat sink of FIG. 2;
Fig. 6 is a perspective view showing a modification of the battery module of Fig. 2;
7 is a cross-sectional view along the XZ-axis in Fig.
8 is a perspective view schematically showing a configuration of a battery module according to still another modification of the present invention.
9 is a cross-sectional view along the XZ-axis in Fig.

Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings. Prior to this, terms and words used in the present specification and claims should not be construed as limited to ordinary or dictionary terms, and the inventor should appropriately interpret the concepts of the terms appropriately It should be construed as meaning and concept consistent with the technical idea of the present invention based on the principle that it can be defined.

Therefore, the embodiments described in this specification and the configurations shown in the drawings are merely the most preferred embodiments of the present invention and do not represent all the technical ideas of the present invention. Therefore, It is to be understood that equivalents and modifications are possible.

In the following description, well-known functions or constructions are not described in detail since they would obscure the invention in unnecessary detail.

The embodiments of the present invention are provided to explain the present invention more fully to the ordinary artisan, so that the shape and size of the components in the drawings may be exaggerated, omitted or schematically shown for clarity. Thus, the size or ratio of each component does not entirely reflect the actual size or ratio.

FIG. 2 is a perspective view schematically showing a configuration of a battery module according to an embodiment of the present invention. FIG. 3 is a cross-sectional view along the XZ-axis of FIG. 2, FIG. 5 is an exploded perspective view of the heat sink of FIG. 2; FIG.

Referring to these drawings, a battery module according to an embodiment of the present invention includes a cell assembly 10, a first cooling plate 20, a second cooling plate 30, and a heat sink 40.

The cell assembly 10 may be composed of a battery cell 11 and a stacking cartridge 12 for supporting the battery cell 11. [

The battery cell 11 may be preferably a pouch type battery cell 11 so as to provide a high laminating ratio in a limited space.

The pouch type battery cell 11 includes an electrode assembly composed of a positive electrode plate, a separator and a negative electrode plate. A plurality of positive electrode tabs and negative electrode tabs protruded from the positive electrode plate and the negative electrode plate of each battery cell 11, And the leads 11b may be electrically connected. The pouch-shaped battery cell 11 may have a structure in which an edge of an outer case is thermally fused and sealed while an electrode assembly is embedded in an outer case of a laminate sheet including a resin layer and a metal layer.

The stacking cartridge 12 is a structure used for stacking the stacks of the battery cells 11 and is configured to hold the battery cells 11 to prevent them from flowing, As shown in FIG.

Referring to FIGS. 2 and 4, the stacking cartridge 12 may be constituted by a first frame 12a and a second frame 12b in the form of a rectangular ring having a hollow center portion. The first frame 12a and the second frame 12b may be provided so as to be assembled with each other by, for example, a hook fastening method. In addition, two battery cells 11 may be disposed in the assembled first and second frames 12a and 12b.

At this time, the rim portion of the battery cell 11 can be positioned at four inner sides of the first and second frames 12a and 12b, and the inner surface portion of the battery cell 11 can be positioned at the first and second frames 12b To be exposed to the outside. The inner surface portion of the battery cell 11 may correspond to the outer surface 11c of the outer case of the battery cell 11 surrounding the electrode assembly portion of the battery cell 11.

That is, the cell assembly 10 according to the present embodiment includes a pair of battery cells 11 and a stacking cartridge 12. A plurality of such cell assemblies 10 are stacked to form a stack structure. For example, as in the present embodiment, a plurality of cell assemblies 10 may be stacked horizontally and laid down and vertically stacked.

The first cooling plate 20 is a plate made of a thermally conductive material and a part of the first cooling plate 20 is interposed between the cell assemblies 10 and the remaining part is disposed in the flow path of the heat sink 40.

Here, the heat sink 40 may have a hollow structure in which a flow path through which refrigerant flows is formed. The coolant flowing through the heat exchanger 40 is not particularly limited as long as the coolant easily flows in the coolant flow path and can be a gas or a liquid. For example, the latent heat is high and can be water that can maximize cooling efficiency. However, the present invention is not limited to this, but a flow may occur, and may be an antifreeze, gas refrigerant, air, or the like. A more detailed description of the heat sink 40 will be described later.

A portion of the first cooling plate 20 interposed between the cell assemblies 10 is defined as a heat absorbing portion 21 and the remaining portion disposed in the flow path of the heat sink 40 is defined as a heat dissipating portion 22).

2 and 3, both surfaces of the heat absorbing portion 21 of the first cooling plate 20 are in close contact with the outer surfaces of the battery cells 11 facing each other, And the heat dissipating unit 22 may be disposed outside the cell assembly 10 and in an internal flow path of the heat sink 40 located at an upper portion of the cell assembly 10. [ The heat of the battery cells 11 is absorbed by the heat absorbing portion 21 of the first cooling plate 20 and can be conducted to the heat dissipating portion 22. [ The heat dissipating unit 22 can be cooled by the refrigerant flowing in the flow path of the heat sink 40.

The first cooling plate 20 may be a thermally conductive metal plate having a thickness of 0.1 to 5.0 mm. With this first cooling plate 20 configuration, the cooling channels in the conventional air-cooled battery module are not required, so that the cell assembly 10 laminate can be made more compact. Also, since the first cooling plate 20 includes predetermined self-mechanical stiffness characteristics, the first cooling plate 20 may reinforce the mechanical rigidity of the battery case 11 which is not excellent.

The thickness and the structure of the first cooling plate 20 are not particularly limited as long as the first cooling plate 20 is a thin member having thermal conductivity. For example, a sheet-shaped metal plate 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. For example, copper, gold, silver. Ceramic materials such as aluminum nitride and silicon carbide other than metals are also possible.

Particularly, the heat dissipating portion 22 of the first cooling plate 20 according to the present embodiment may include a plurality of through holes 23. 4, the refrigerant flowing on the flow path of the heat sink 40 may flow through the plurality of first cooling plates 20 arranged in a superposed manner through the through holes 23. [ At this time, the turbulent flow can be promoted around the through hole 23. When the turbulent flow is promoted, the heat exchange between the upper and lower stratified flows in the flow path of the heat sink 40 becomes smooth, the convection heat transfer rate increases, and the cooling efficiency of the heat radiation portion 22 can be further improved.

On the other hand, the second cooling plate 30 may be a plate-like structure that is horizontally disposed in the flow path of the coolant in the flow path of the heat sink 40. The second cooling plate 30 may be positioned in the flow path in such a manner that its lower surface is connected to the upper end of the plurality of first cooling plates 20. [

The second cooling plate 30 absorbs heat from the plurality of first cooling plates 20 and releases heat by convective heat transfer. Here convective heat transfer means that heat is transferred between the fluid and the surface of the solid as a result of the relative motion of the fluid with respect to the surface if the temperature of the fluid and the solid surface is different when the fluid is flowing over or over the solid.

The convective heat transfer rate is determined on the basis of the geometry of the solid surface, fluid type, fluid characteristics, fluid velocity, etc. Generally, it is proportional to the fluid flow rate and increases as the effective heat radiation area increases. 2 and 3, the second cooling plate 30 according to the present invention is disposed on the flow path of the heat sink 40, and is configured such that the surface thereof is arranged in parallel with the flow of the refrigerant do.

This second cooling plate 30 has a wide effective heat dissipation area so that convective heat transfer can occur very quickly. As a result, the second cooling plate 30 forms a relatively low temperature relative to the first cooling plates 20.

The temperature gradient between the second cooling plate 30 and the first cooling plates 20 is increased so that the heat of the battery cells 11 is transmitted to the second cooling plate 30 through the first cooling plate 20 So that the cooling performance of the battery module can be further improved.

The second cooling plate 30 may be integrally formed with the first cooling plate 20. By forming the second cooling plate 30 and the first cooling plate 20 integrally, the thermal contact resistance between them can be reduced and the thermal conductivity can be increased.

5, the heat sink 40 according to the present embodiment includes a heat sink lower plate 41 and a heat sink upper plate 42 which are vertically assembled.

The heat sink bottom plate 41 has a plurality of slots 41a formed vertically. The plurality of first cooling plates 20 can pass through the body of the heat sink lower plate 41 through the plurality of slots 41a.

The heat sink upper plate 42 is configured to be assembled to the heat sink lower plate 41. That is, after the first and second cooling plates 30 and the heat sink lower plate 41 are integrated, the heat sink lower plate 42 is covered with the heat sink upper plate 42 to form a flow path. And the heat sink 40 may be connected to separate ducts (not shown). That is, by connecting another duct to the inlet and outlet sides of the heat sink 40, the flow path can be extended.

The heat sink 40 may be located on one side of the cell assembly 10 stack. That is, in the present embodiment, the heat sink 40 is disposed above the cell assembly 10, but the scope of the present invention is not limited thereto. For example, the cell assembly 10 may be located at one or both of a side surface and a lower surface of the cell assembly 10 according to the installation space or the stacking direction of the cell assembly 10.

As described above, according to the present invention, the structure of the cooling channel, the cooling tube, and the like located in the battery cells 11 having the conventional stack structure can be omitted, so that the module structure can be simplified and compact. In addition, the heat of the battery cells 11 can be quickly discharged to the heat sink 40 by the first cooling plate 20 and the second cooling plate 30, so that the cooling performance of the battery module can be further improved.

Next, a battery module according to a modification of the embodiment described with reference to Figs. 6 and 7 will be briefly described.

6 is a modification of the battery module shown in FIG. 2, in which the plurality of second cooling plates 30 are layered at regular intervals, so that the first cooling plate (20) and the second cooling plate (30).

Particularly, the heat radiating portion 22 of the first cooling plate 20 is provided in a lattice form in a grating structure and is disposed perpendicular to the plurality of second cooling plates 30.

According to this modification, the heat radiating portion 22 of the first cooling plate 20 is provided in a grating structure, so that the turbulent flow and the ventilation of the coolant can be improved between the first cooling plates 20. That is, since the air permeability is improved, the pressure loss inside the heat sink 40 can be reduced. Further, since the plurality of second cooling plates 30 are provided, the effective heat dissipation area is further increased, so that the cooling efficiency can be further improved.

Next, a battery module according to still another modification of the present invention will be briefly described with reference to Figs. 8 and 9. Fig.

The present modification shown in Figs. 8 and 9 is substantially the same as the previous modification, except that the arrangement structure between the heat sink 40 and the cell assembly 10 laminate is changed. Therefore, in the following description, duplicated description will be omitted and differences will be mainly described.

If the embodiment of FIG. 2 described above assumes that the heat sink 40 is disposed such that the flow of the refrigerant is from the right side to the left side of the cell assembly 10 stack, ) The heat sink 40 is disposed so as to face the rear surface from the front surface of the stacked body.

In other words, in the above-described embodiment, the first cooling plates 20 are arranged side by side in the vertical direction while the first cooling plates 20 are arranged in the longitudinal direction in the coolant flow direction. Therefore, since the battery module according to the present modification has a structure in which the refrigerant can flow along both surfaces of the heat dissipating portion 22 of the first cooling plate 20, the effective heat dissipating area can be widened, The pressure loss inside the flow path of the fluid can be reduced.

The battery pack according to the present invention may include at least one battery module according to the present invention. In addition to the battery module, the battery pack may further include a case for covering the battery module, and various devices for controlling charge and discharge of the battery module, such as a BMS, a current sensor, a fuse, and the like.

The battery pack according to the present invention can be applied to an automobile such as an electric car or a hybrid car. That is, the automobile according to the present invention may include a battery module according to the present invention.

While the present invention has been particularly shown and described with reference to exemplary embodiments thereof, it is to be understood that the invention is not limited to the disclosed exemplary embodiments. It will be understood that various modifications and changes may be made without departing from the scope of the appended claims.

In the present specification, terms indicating upward, downward, leftward, and rightward directions are used, but these terms are for convenience of explanation only, and may vary depending on the position of the object or the position of the observer. Lt; / RTI >

10: cell assembly 11: battery cell
12: stacking cartridge 20: first cooling plate
21: heat absorbing portion 22: heat dissipating portion
23: through hole 30: second cooling plate
40: Heatsink

Claims (11)

A plurality of cell assemblies each having a battery cell and a stacking cartridge for supporting the battery cell and stacked in a horizontal or vertical direction;
A heat sink having a hollow structure, which is located at one side of the plurality of cell assemblies arranged in layers and in which a flow path for flowing coolant is formed.
A plurality of first cooling plates interposed between the cell assemblies, the remainder being disposed in the flow path of the heat sink to absorb heat from the cell assemblies; And
And a second cooling plate disposed on the flow path of the heat sink and connected to the plurality of first cooling plates and absorbing heat from the plurality of first cooling plates to dissipate heat on the flow paths. Battery module. The method according to claim 1,
Wherein the first cooling plate has at least one through-hole for passing the refrigerant therethrough. The method according to claim 1,
Wherein the second cooling plate is provided in a plate shape and the plate surface is disposed horizontally with respect to the flow direction of the coolant. The method of claim 3,
A plurality of second cooling plates are provided,
Wherein the plurality of second cooling plates are arranged in a laminar manner at equal intervals. 5. The method of claim 4,
Wherein a portion of the first cooling plate disposed in the flow path of the heat sink is provided in a lattice form in a grating structure and is vertically disposed to the plurality of second cooling plates. The method according to claim 1,
The heat sink
A heat sink lower plate mounted on one side of the cell assembly and having a plurality of slots such that the plurality of first cooling plates pass through the body; And
And a heat sink upper plate coupled to the heat sink lower plate to form a flow path therein. The method according to claim 1,
The stacking cartridge includes:
And a first frame and a second frame each of which is formed in a quadrangular ring shape and is assembled with at least one battery cell interposed therebetween so that at least one side of the battery cell is exposed to the outside Battery module. The method according to claim 1,
Wherein the first cooling plate and the second cooling plate are integrally formed. The method according to claim 1,
Wherein the plurality of first cooling plates are arranged in parallel in a transverse direction with respect to a flow direction of the refrigerant. A battery pack comprising the battery module according to any one of claims 1 to 9. An automobile comprising a battery module according to any one of claims 1 to 9.

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