Title of Invention: Battery module and battery pack including same
technical field
[One]
Cross-Citation with Related Application(s)
[2]
This application claims the benefit of priority based on Korean Patent Application No. 10-2020-0043243 dated April 09, 2020, and all contents disclosed in the literature of the Korean patent application are incorporated as a part of this specification.
[3]
The present invention relates to a battery module and a battery pack including the same, and more particularly, to a battery module for improving cooling performance and a battery pack including the same.
background
[4]
Secondary batteries are receiving a lot of attention as an energy source in various product groups such as mobile devices and electric vehicles. Such a secondary battery is a powerful energy resource that can replace the use of conventional products using fossil fuels, and is in the spotlight as an eco-friendly energy source because no by-products are generated according to energy use.
[5]
Recently, as the need for a high-capacity secondary battery structure, including the use of secondary batteries as an energy storage source, increases, the demand for a battery pack having a multi-module structure in which a plurality of secondary batteries are assembled in series/parallel connected battery pack is increasing. .
[6]
On the other hand, when configuring a battery pack by connecting a plurality of battery cells in series/parallel, a battery module composed of battery cells is configured, and other components are added using at least one battery module to configure the battery pack. How to do it is common
[7]
The battery module includes a battery cell stack in which a plurality of battery cells are stacked, a module frame accommodating the battery cell stack, and a heat sink for cooling the plurality of battery cells.
[8]
1 is a view showing a battery module combined with a conventional heat sink. FIG. 2 is a plan view illustrating a flow path structure of the heat sink of FIG. 1 . FIG. 3 is a view showing a state in which a refrigerant flows in the flow path structure of FIG. 2 .
[9]
1 to 3 , a conventional battery module includes a battery cell stack in which a plurality of battery cells 10 are stacked, a module frame accommodating the battery cell stack, a bottom portion 20 of the module frame and the and a thermally conductive resin layer 15 positioned between the battery cell stacks. Such a battery module may be formed under the module frame bottom 20 and combined with a heat sink 30 that provides a cooling function to the plurality of battery cells 10 to form a battery pack. At this time, the heat sink 30 includes a lower plate 31 having an inlet 32 ​​through which the refrigerant flows, an outlet 33 through which the refrigerant flows, and a cooling passage 34 connecting the inlet 32 ​​and the outlet 33 . ), and an upper plate 29 covering the lower plate 31 . Here, a heat-conducting layer 18 may be further formed between the bottom 20 of the battery module and the heat sink 30 .
[10]
Conventionally, in order to improve the cooling performance of the battery module and/or the battery pack, a separate cooling structure, for example, a heat sink is required in the battery pack unit. Accordingly, the cooling structure tends to be complicated. In addition, in order to minimize the pressure drop of the refrigerant flowing inside the heat sink, a structure in which the length of the flow path is shortened and the width is increased as shown in FIG. 2 was adopted, but as shown in FIG. 3, the flow path 34 ), a temperature deviation may occur between the middle and both sides of the width of the flow path. When a temperature deviation occurs on the flow path, the cooling of the battery cell stack is not uniformly performed, so that the overall cooling performance of the battery module may be deteriorated.
DETAILED DESCRIPTION OF THE INVENTION
technical challenge
[11]
SUMMARY OF THE INVENTION An object of the present invention is to provide a battery module and a battery pack that improve cooling performance.
[12]
The problems of the present invention are not limited to the problems mentioned above, and other problems not mentioned will be clearly understood by those skilled in the art from the following description.
means of solving the problem
[13]
A battery module according to an embodiment of the present invention for realizing the above object includes: a battery cell stack in which a plurality of battery cells are stacked; a module frame for accommodating the battery cell stack; and a heat sink formed under the module frame to cool the plurality of battery cells, wherein the heat sink includes a lower plate, a flow path portion serving as a flow path of the refrigerant, and a flow path portion along a direction in which the flow passage portion is formed. and a partition wall formed therein, wherein the lower plate is coupled to the bottom of the module frame.
[14]
The partition wall may be coupled to a bottom portion of the module frame.
[15]
The flow path part has a structure recessed downward from the lower plate, the upper side of the flow path part is covered by the bottom part of the module frame, and a refrigerant may flow into a space between the flow path part and the bottom part of the module frame.
[16]
The heat sink may further include an inlet through which the refrigerant flows and an outlet through which the refrigerant flows, and a starting point of the partition wall may be formed to be spaced apart from the inlet.
[17]
The refrigerant introduced through the inlet may flow separately from the starting point of the partition wall into a first flow path part and a second flow path part.
[18]
The width of the first and second flow passages may be uniformly formed from the inlet to the outlet.
[19]
The partition wall may extend from the inlet to the outlet along a central portion of the flow passage.
[20]
A portion where the flow passage is bent may be formed as a curved surface.
[21]
The lower plate may be formed to correspond to a lower surface of the module frame.
[22]
A battery pack according to another embodiment of the present invention includes the battery module.
Effects of the Invention
[23]
According to the embodiments of the present invention, the barrier rib structure is formed without changing the channel length to minimize the pressure drop due to the flow of the refrigerant, and at the same time, the temperature deviation between the channel widths can be reduced by reducing the channel width through the barrier ribs, so that the battery module can improve the cooling performance of
[24]
In addition, the cooling structure can be simplified through the cooling structure in which the module frame and the heat sink are integrated.
[25]
Effects of the present invention are not limited to the effects mentioned above, and other effects not mentioned will be clearly understood by those skilled in the art from the description of the claims.
Brief description of the drawing
[26]
1 is a view showing a battery module combined with a conventional heat sink.
[27]
FIG. 2 is a plan view illustrating a flow path structure of the heat sink of FIG. 1 .
[28]
FIG. 3 is a view showing a state in which a refrigerant flows in the flow path structure of FIG. 2 .
[29]
4 is an exploded perspective view of a battery module according to an embodiment of the present invention.
[30]
FIG. 5 is a view showing a state in which the components of the battery module of FIG. 4 are assembled.
[31]
6 is a view of the battery module assembled in FIG. 5 centered on the heat sink formed on the lower part.
[32]
FIG. 7 is a cross-sectional view illustrating the heat sink of FIG. 6 cut in a horizontal direction and viewed in a direction AA;
[33]
FIG. 8 is a view illustrating a state in which a refrigerant flows through the heat sink of FIG. 7 .
[34]
FIG. 9 is a view showing a modified example of the heat sink of FIG. 7 .
[35]
FIG. 10 is a diagram illustrating a modified example of the heat sink of FIG. 7 .
[36]
FIG. 11 is a diagram illustrating a modified example of the heat sink of FIG. 7 .
Modes for carrying out the invention
[37]
It should be understood that the embodiments described below are illustratively shown to aid understanding of the invention, and the present invention may be implemented with various modifications different from the embodiments described herein. However, in the description of the present invention, if it is determined that a detailed description of a related known function or component may unnecessarily obscure the gist of the present invention, the detailed description and detailed illustration thereof will be omitted. In addition, the accompanying drawings are not drawn to scale in order to help understanding of the invention, but dimensions of some components may be exaggerated.
[38]
The first and second terms used in the present application may be used to describe various components, but the components should not be limited by the terms. The terms are used only for the purpose of distinguishing one component from another.
[39]
In addition, the terms used in the present application are only used to describe specific embodiments, and are not intended to limit the scope of rights. The singular expression includes the plural expression unless the context clearly dictates otherwise. In this application, terms such as "comprises", "consists of" or "consisting It should be understood that it does not preclude the possibility of addition or existence of further other features or numbers, steps, operations, components, parts, or combinations thereof.
[40]
Hereinafter, a configuration of a battery module according to an embodiment of the present invention will be described with reference to FIGS. 4 and 5 .
[41]
4 is an exploded perspective view of a battery module according to an embodiment of the present invention. FIG. 5 is a view showing a state in which the components of the battery module of FIG. 4 are assembled.
[42]
4 and 5 , the battery module 200 according to an embodiment of the present invention includes a battery cell stack 100 in which a plurality of battery cells are stacked, and a module for accommodating the battery cell stack 100 . The frame 205 and a heat sink 300 formed under the module frame 205 to cool the plurality of battery cells is included.
[43]
The battery cell according to this embodiment is a secondary battery, and may be configured as a pouch-type secondary battery. The battery cells may be configured in plurality, and the plurality of battery cells may be stacked to each other so as to be electrically connected to each other to form the battery cell stack 100 . Each of the plurality of battery cells may include an electrode assembly, a cell case, and an electrode lead protruding from the electrode assembly.
[44]
The module frame 205 accommodates the battery cell stack 100 . According to an embodiment of the present invention, the module frame 205 includes a lower frame 210 covering the lower surface and both sides of the battery cell stack 100 , and an upper plate covering the upper surface of the battery cell stack 100 ( 220) may be included. However, the structure of the module frame 205 is not limited thereto, and may be in the form of a mono frame surrounding the four sides except for the front and rear surfaces of the battery cell stack 100 .
[45]
The battery module 200 according to the present embodiment may further include an end plate 230 covering the front and rear surfaces of the battery cell stack 100 . It is possible to physically protect the battery cell stack 100 accommodated therein through the module frame 205 described above.
[46]
The heat sink 300 may be formed under the module frame 205 . The heat sink 300 is formed on one side of the lower plate 310 and the heat sink 300 forming a skeleton of the heat sink 300 and in contact with the bottom of the module frame 205 to form the heat sink 300 from the outside. ) The inlet 320 for supplying the refrigerant to the inside, the outlet 330 formed on one side of the heat sink to allow the refrigerant flowing inside the heat sink to flow out of the heat sink, and the inlet 320 and the outlet 330 are connected and a flow path part 340 through which the refrigerant flows.
[47]
According to the present embodiment, the partition wall 350 is formed in the flow path part 340 in the direction in which the flow path part 340 is formed. The lower plate 310 and the partition wall 350 may be coupled to the bottom of the module frame 205 by a method such as welding.
[48]
Specifically, the flow path 340 may refer to a structure in which the lower plate 310 in contact with the lower surface of the lower frame 210 corresponding to the bottom of the module frame 205 is depressed downward. The upper side of the flow path part 340 is opened to form a flow path between the flow path part 340 and the bottom of the module frame 205 , and a refrigerant may flow through the flow path. In other words, the battery module 200 according to the present embodiment may have a cooling-integrated structure in which the bottom of the module frame 205 serves to correspond to the upper plate of the heat sink 300 .
[49]
Conventionally, a structure in which a refrigerant flows is separately formed on the lower side of the module frame, so that the module frame cannot but be indirectly cooled, so cooling efficiency is lowered and a separate refrigerant flow structure is formed on the battery module and the battery pack equipped with the battery module. There was a problem that the space utilization rate was lowered. However, according to an embodiment of the present invention, by adopting a structure in which the heat sink 300 is integrated in the lower part of the module frame 205 , the refrigerant flows directly between the flow path part 340 and the bottom part of the module frame 205 . As a result, the cooling efficiency due to direct cooling increases, and the space utilization rate on the battery module and the battery pack on which the battery module is mounted is further improved through the structure in which the heat sink 300 is integrated with the bottom of the module frame 205 . can do it
[50]
In addition, in the case of a large-area battery module in which the number of stacked battery cells is increased a lot compared to the prior art, such as the battery cell stack 100 according to an embodiment of the present invention, the width of the flow path can be formed wider, so that the temperature deviation is reduced. It could be worse.
[51]
The barrier rib 350 according to the present exemplary embodiment reduces the width of the flow path part 340 without changing the flow path length of the flow path part 340 to minimize the pressure drop and at the same time reduce the temperature deviation between the flow path widths. The upper end of the partition wall 350 and the upper end of the lower plate 310 may be coupled to the lower surface of the module frame 205 by a method such as welding. By the partition wall 350 , the pressure drop and temperature deviation of the flowing refrigerant can be minimized, and in addition to the lower plate 210 , the partition wall 350 is also combined with the bottom of the module frame 205 to form the module frame 205 . ) and may have an effect of supporting the load of the battery cell stack 100 accommodated in the module frame 205 and reinforcing the rigidity of the battery module 200 .
[52]
Hereinafter, a heat sink structure according to an embodiment of the present invention will be described in more detail with reference to FIGS. 6 to 8 .
[53]
6 is a view of the battery module assembled in FIG. 5 centered on the heat sink formed on the lower part. FIG. 7 is a cross-sectional view illustrating the heat sink of FIG. 6 cut in a horizontal direction and viewed in a direction AA; FIG. 8 is a view illustrating a state in which a refrigerant flows through the heat sink of FIG. 7 .
[54]
6 to 8 , in the heat sink 300 according to an embodiment of the present invention, the lower plate 310 may be formed to correspond to the bottom of the module frame 205 . The bottom of the module frame 205 corresponds to the bottom of the lower frame 210 , and the bottom of the lower plate 310 and the lower frame 210 may be joined by welding, and the battery module through the lower plate 310 . The overall rigidity can be reinforced. Since the bottom of the lower plate 310 and the lower frame 210 are sealed through welding, the refrigerant may flow through the flow path 340 formed inside the lower plate 310 without leakage.
[55]
Both the inlet 320 and the outlet 330 may be formed on one side of the heat sink 300 . In more detail, both the inlet 320 and the outlet 330 may be formed on one side of the heat sink 300 formed in the portion where the end plate 230 is located. The inlet 320 and the outlet 330 may be respectively located at both ends of one side of the heat sink 300 . A refrigerant supply unit and a refrigerant discharge unit are formed on the lower side or upper side of the heat sink 300 , so that the refrigerant supplied through the refrigerant supply unit may flow into the inlet 320 , and the refrigerant discharged through the outlet 330 may be discharged through the refrigerant discharge unit. can be discharged to the outside.
[56]
The flow path 340 may be formed to cover the bottom of the module frame 205 while being bent. The flow path part 340 is formed in most regions of the bottom part of the module frame 205 except for the part in which the lower plate 310 is in contact with the bottom part of the module frame 205 , so that the upper part of the bottom part of the module frame 205 is formed. All parts of the battery cell stack 100 arranged to occupy most of the area of ​​the bottom of the module frame 205 may be uniformly cooled.
[57]
A portion where the flow passage 340 is bent may be formed as a curved surface. Accordingly, a portion where the partition wall 350 is bent may also be formed as a curved surface. When an angled corner portion is formed in the flow path portion 340 , the flow of the refrigerant is stagnated at the angled corner portion, and there is a risk that the temperature deviation and pressure drop may increase. In this regard, if the bent portion is treated as a curved surface as in an embodiment of the present invention, the flow of the refrigerant may be made naturally.
[58]
The partition wall 350 may extend from the inlet 320 to the outlet 330 along a central portion of the flow path 340 . Through this, the refrigerant introduced into the inlet 320 may be guided to the outlet 330 along the partition wall 350 .
[59]
The starting point of the partition wall 350 is formed to be spaced apart from the inlet 320 , and the refrigerant introduced through the inlet 320 flows from the starting point of the partition wall 350 to the first flow path portion 341 and the second flow path formed through the partition wall 350 . It can flow by being divided into two flow passages 342 . In this case, the widths of the first flow path part 341 and the second flow path part 342 are formed to be the same, and the widths of the first flow path part 341 and the second flow path part 342 are from the inlet 320 to the outlet 340 . ) can be consistently formed. Accordingly, the flow may not be biased toward any one of the first and second flow passages 341 and 342 , and a flow passage that may occur due to a wider width of one of the first and second flow passages 341 and 342 . It is possible to minimize the difference in temperature deviation between each. In addition, since the widths of the flow passages 340 are uniformly formed, it is possible to minimize the possibility of pressure drop and temperature deviation that may occur when the width is increased or decreased.
[60]
9 to 11 are views illustrating modified examples of the heat sink of FIG. 7 .
[61]
9 to 11 , according to embodiments, the barrier rib 350 described with reference to FIG. 7 may implement a heat sink having the barrier rib structures 450 , 550 , and 650 modified in various shapes.
[62]
The battery module described above may be included in the battery pack. The battery pack may have a structure in which one or more battery modules according to the present embodiment are collected and a battery management system (BMS) that manages the temperature, voltage, etc. of the battery and a cooling device are added and packed.
[63]
The battery pack may be applied to various devices. These devices can be applied to transportation means such as electric bicycles, electric vehicles, hybrid vehicles, etc., but the present invention is not limited thereto and can be applied to various devices that can use a battery module, which also falls within the scope of the present invention. .
[64]
In the above, preferred embodiments of the present invention have been illustrated and described, but the present invention is not limited to the specific embodiments described above, and it is common in the technical field to which the present invention pertains without departing from the gist of the present invention as claimed in the claims. Various modifications are possible by those having the knowledge of, of course, and these modifications should not be individually understood from the technical spirit or perspective of the present invention.
[65]
Explanation of symbols
[66]
205: module frame
[67]
210: lower frame
[68]
220: upper plate
[69]
300: heat sink
[70]
310: lower plate
[71]
320: inlet
[72]
330: outlet
[73]
340: euro
[74]
341: 1st Euro
[75]
342: 2nd Euro
[76]
350: bulkhead
[77]
Claims
[Claim 1]
a battery cell stack in which a plurality of battery cells are stacked; a module frame for accommodating the battery cell stack; and a heat sink formed under the module frame to cool the plurality of battery cells, wherein the heat sink includes a lower plate, a flow path portion serving as a flow path of the refrigerant, and a flow path portion along a direction in which the flow passage portion is formed. A battery module comprising a partition wall formed therein, wherein the lower plate is coupled to the bottom of the module frame.
[Claim 2]
The battery module of claim 1, wherein the partition wall is coupled to a bottom portion of the module frame.
[Claim 3]
According to claim 1, wherein the flow passage has a structure recessed downward from the lower plate, the upper side of the flow passage is covered by the bottom of the module frame, the refrigerant into a space between the flow passage and the bottom of the module frame a flowing battery module.
[Claim 4]
The battery module of claim 1 , wherein the heat sink further includes an inlet through which the refrigerant flows and an outlet through which the refrigerant flows, and the starting point of the partition wall is formed to be spaced apart from the inlet.
[Claim 5]
5 . The battery module of claim 4 , wherein the refrigerant introduced through the inlet flows separately from a starting point of the partition wall into a first flow path part and a second flow path part.
[Claim 6]
The battery module of claim 5, wherein the widths of the first and second flow passages are uniformly formed from the inlet to the outlet.
[Claim 7]
The battery module of claim 5 , wherein the partition wall extends from the inlet to the outlet along a central portion of the flow passage.
[Claim 8]
The battery module of claim 7 , wherein the portion where the flow passage is bent is formed in a curved surface.
[Claim 9]
The battery module of claim 1, wherein the lower plate is formed to correspond to a lower surface of the module frame.
[Claim 10]
A battery pack comprising the battery module according to claim 1 .