[One]Cross-Citation with Related Application(s)
[2]
This application claims the benefit of priority based on Korean Patent Application No. 10-2019-0133055 dated October 24, 2019, 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 using insulating oil 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 due to energy use.
[5]
Recently, as the need for a large-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 at least one battery cell is configured, and other components are added using the at least one battery module to add other components to the battery pack. The general way to configure
[7]
Such a battery module includes a battery cell stack in which a plurality of battery cells are stacked, electrode leads protruding from the battery cells, a frame that covers the top, bottom, left and right surfaces of the battery cell stack, and a battery cell stack and an end plate covering the front and rear surfaces of the
[8]
It is important to use the lithium-ion battery module at an appropriate temperature because the deterioration of lifespan is accelerated at high temperatures. To this end, most lithium-ion battery modules are cooled by air cooling or water cooling, and the existing cooling structure employs a method of cooling through several interfaces. However, there is a problem in that each interface increases thermal resistance, and each part increases the weight of the vehicle.
[9]
In addition, the positive electrode and the case of the battery module must maintain insulation performance at all times and must not be destroyed even when a high voltage is applied. However, there is a problem in that it is difficult to secure a sufficient insulation distance only by designing a layout to reduce the weight and volume of the battery module.
[10]
1 is an exploded perspective view showing a conventional battery module.
[11]
Conventionally, a plurality of battery cells are stacked in a battery cell stack 10 , a frame 20 accommodating the battery cell stack 10 , formed between the lower side of the battery cell stack 10 and the lower surface of the frame 20 . Thermal resin 30 to transfer heat, the thermal pad 40 to transfer heat by being located under the thermal resin 30, and the heat sink 50 to be located under the thermal pad 40 to transfer heat Through the configurations of , a function of discharging heat generated from a plurality of battery cells to the outside was performed.
[12]
However, as described above, in the conventional cooling system that performs cooling through several steps of configuration, as each configuration is added, the weight of the battery module increases, and thermal resistance increases due to going through each configuration step, and the Due to the density of components for volume reduction, it was difficult to secure an insulation distance between the positive electrode of the battery module and the case.
DETAILED DESCRIPTION OF THE INVENTION
technical challenge
[13]
SUMMARY OF THE INVENTION An object of the present invention is to provide a battery module and a battery pack including the same, which reduce weight and thermal resistance and secure insulation performance.
[14]
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
[15]
A battery module according to an embodiment of the present invention for realizing the above object is a battery cell stack in which battery cells formed of an edge surface and a flat surface are stacked, electrode leads protruding from the battery cells, upper, lower, left, and right surfaces and an end plate formed to cover the upper, lower, left and right surfaces of the battery cell stack and an end plate for covering the front and rear surfaces of the battery cell stack, and between the edge surfaces of the battery cell and the frame and the end plate A space portion is formed in the space portion, and insulating oil for cooling the plurality of battery cells is filled and flows, and the insulating oil is in contact with the battery cells and the electrode leads.
[16]
The space portion, the first space portion formed between the edge surfaces of the battery cells formed on the front surface of the battery cell stack and a first end plate covering the front surface of the battery cell stack, the upper side of the battery cell stack A second space formed between the edge surfaces of the battery cells formed in the upper surface of the frame and the third space formed between the edge surfaces of the battery cells formed on the lower side of the battery cell stack and the lower surface of the frame and a fourth space formed between the edge surfaces of the battery cells formed on the rear surface of the battery cell stack and a second end plate that covers the rear surface of the battery cell stack.
[17]
The first and fourth space portions may be formed in a space between the end plate and the edge surfaces formed in two battery cells adjacent to each other.
[18]
The second and third space portions may be formed in a space between the frame and the edge surfaces formed in two adjacent battery cells.
[19]
The insulating oil may flow from the first space to the fourth space through the second space or the third space of the battery cell stack.
[20]
A supply unit to which the insulating oil is supplied may be formed at an upper end of the first end plate, and a discharge unit through which the insulating oil is discharged may be formed at a lower end of the second end plate.
[21]
The electrode leads may protrude from both ends of the battery cells into the first and fourth spaces, respectively, and contact the insulating oil flowing in the first and fourth spaces.
[22]
The end plate and the frame may be coupled with an adhesive, and the end plate and the frame may be sealed through the adhesive.
[23]
It further includes a bus bar frame formed between the end plate and the battery cell stack, wherein the bus bar frame is positioned on the space portion to be in contact with the insulating oil.
Effects of the Invention
[24]
A battery module and a battery pack including the same according to an embodiment of the present invention are insulated by replacing the conventional components for cooling the battery cell with an insulating oil, thereby reducing thermal resistance and weight, and allowing the battery cell and the insulating oil to directly contact It provides the effect of improving performance.
[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 an exploded perspective view showing a conventional battery module.
[27]
2 is an exploded perspective view showing a battery module according to an embodiment of the present invention.
[28]
3 is a perspective view illustrating a battery cell according to an embodiment of the present invention.
[29]
4 is a view showing the flow of insulating oil according to an embodiment of the present invention.
[30]
FIG. 5 is a cross-sectional view showing second and third space portions filled with insulating oil in a portion A-A' of FIG. 4 .
[31]
6 is a cross-sectional view showing the first and fourth spaces filled with insulating oil in the portion B-B' of FIG. 4 .
[32]
7 is a view showing a supply unit and a discharge unit according to an embodiment of the present invention.
[33]
8 is a view showing the flow of insulating oil according to an embodiment of the present invention.
[34]
9 is a view showing a connection flow path between battery modules according to an embodiment of the present invention.
Modes for carrying out the invention
[35]
It should be understood that the embodiments described below are illustratively shown to help understanding of the invention, and that 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 specific 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.
[36]
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.
[37]
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 the present application, terms such as "comprises", "consists of" or "consisting It should be understood that this does not preclude the possibility of addition or existence of other features or numbers, steps, operations, components, parts, or combinations thereof.
[38]
Hereinafter, a battery module according to an embodiment of the present invention will be described with reference to FIGS. 2 to 6 .
[39]
2 is an exploded perspective view showing a battery module according to an embodiment of the present invention. 3 is a perspective view illustrating a battery cell according to an embodiment of the present invention. 4 is a view showing the flow of insulating oil according to an embodiment of the present invention. FIG. 5 is a cross-sectional view showing second and third space portions filled with insulating oil in a portion A-A' of FIG. 4 . 6 is a cross-sectional view showing the first and fourth spaces filled with insulating oil in the portion B-B' of FIG. 4 .
[40]
2 to 6 , in the battery module according to an embodiment of the present invention, the battery cells 110 formed of edge surfaces 110a, 110b, 110c, 110d and flat surfaces 110e and 110f are stacked. The battery cell stack 100, the electrode leads 120 protruding from the battery cells 110, the frame 200 formed of top, bottom, left, and right surfaces to cover the top, bottom, left, and right surfaces of the battery cell stack 100 and Including an end plate 300 covering the front and rear surfaces of the battery cell stack 100, the edge surfaces 110a, 110b, 110c, 110d of the battery cell 110, and the frame 200 and the end plate ( A space 400 is formed between 300), and the space 400 is filled with insulating oil I for cooling the plurality of battery cells 110 and flows, and the insulating oil I is used for the battery cells 110 and the electrode. contacts the leads 120 .
[41]
The battery cell 110 is a secondary battery and may be configured as a pouch-type secondary battery. The battery cells 110 may be configured in plurality, and the plurality of battery cells 110 may be stacked to each other so as to be electrically connected to each other to form the battery cell stack 100 . As shown in FIG. 3 , the plurality of battery cells 110 are formed to extend from the edges of the flat surfaces 110e and 110f forming the case, respectively, and the edge surfaces in four directions to seal the electrode assembly inside the case. (110a, 110b, 110c, 110d), and the electrode lead 120 protruding from the electrode assembly may be included.
[42]
The bus bar frame 130 may be formed between the end plate 300 and the battery cell stack 100 to cover the front and rear surfaces of the battery cell stack 100 and electrically connect the electrode leads 120 to each other. . The bus bar frame 130 is positioned on the first space portion 410 and the fourth space portion 440 of the space portion 400 to be described later and flows in the first and fourth space portions 410 and 440 . May be in contact with insulating oil (I).
[43]
The frame 200 may accommodate the battery cell stack 100 on upper, lower, left, and right surfaces of the battery cell stack 100 . According to an embodiment of the present invention, the second space 420 and the frame lower surface 220 and the battery cell stack 100 formed between the upper surface of the frame upper surface 210 and the upper side of the battery cell stack 100 . The third space 430 formed between the lower portions may be filled with insulating oil I to flow.
[44]
The end plate 300 is formed to cover the front and rear surfaces of the battery cell stack 100 , and may physically protect the battery cell stack 100 , the bus bar frame 130 , and other electronic devices connected thereto. In addition, the end plate 310 may include a structure for mounting the battery module to the battery pack.
[45]
According to an embodiment of the present invention, the end plate 300 may be coupled to the frame 200 with an adhesive. The end plate 300 and the frame 200 are sealingly coupled through an adhesive, so that the insulating oil I, which is filled and flows inside the end plate 300 and the frame 200, does not leak out of the battery module. Before bonding the end plate 300 and the frame 200 , welding may be performed locally to a portion of the joint between the end plate 300 and the frame 200 to fix the bonding position of each component.
[46]
The end plate 300 may include a first end plate 310 formed on the front surface of the battery cell stack 100 , and a second end plate 320 formed on the rear surface of the battery cell stack body 100 .
[47]
The space part 400 is formed between the edge surfaces 110a, 110b, 110c, 110d of the battery cells 110 and the frame 200 and the end plate 300, and the space part 400 has a plurality of battery cells. The insulating oil (I) for cooling the 110 is filled and flows, and the insulating oil (I) comes into contact with the battery cell 110 and the electrode leads 120 to cool the heat generated in the plurality of battery cells 110 . there is.
[48]
The space 400 is a first end plate 310 that covers the edge surfaces 110a of the battery cells 110 formed on the front surface of the battery cell stack 100 and the front surface of the battery cell stack 100 . A first space 410 formed therebetween, a second space formed between the edge surfaces 110b of the battery cells 110 formed on the upper side of the battery cell stack 100 and the upper surface 210 of the frame 200 . Part 420 , the third space 430 formed between the edge surfaces 110c of the battery cells 110 formed on the lower side of the battery cell stack 100 and the lower surface 220 of the frame 200 , and the battery A fourth space ( 440) may be included.
[49]
According to an embodiment of the present invention, the first and fourth space portions 410 and 440 are to be formed in a space between the edge surfaces 110a and 110d formed in two adjacent battery cells and the end plate 300 . can More specifically, the first space portion 410 may be formed in the space between the first end plate 310 and the edge surfaces 110a formed in two adjacent battery cells. The fourth space 440 may be formed in a space between the edge surfaces 110d formed on two adjacent battery cells and the second end plate 320 .
[50]
The electrode leads 120 are disposed on the first and fourth spaces 410 and 440, respectively, so that the insulating oil I flowing by filling the first and fourth spaces 410 and 440 and the electrode leads 120 are in direct contact with each other. can do. Since the electrode lead 120 is a portion that generates the most heat in the battery cell 110 , the electrode lead 120 and the insulating oil I directly contact through the first and fourth spaces 410 and 440 , so that the battery The cooling performance of the entire module can be enhanced.
[51]
The second and third spaces 420 and 430 may be formed in a space between the frame 200 and the edge surfaces 110b and 110c formed on two battery cells adjacent to each other. More specifically, the second space 420 may be formed in a space between the edge surfaces 110b formed on two adjacent battery cells and the upper surface 210 of the frame. The third space 430 may be formed in a space between the edge surfaces 110c formed on two adjacent battery cells and the lower surface of the frame 220 .
[52]
According to an embodiment of the present invention, space portions 410 , 420 , 430 , 440 are formed on the edge surfaces 110a , 110b , 110c and 110d of the battery cell 110 , and the insulating oil I is disposed in the space. Since the parts 410 , 420 , 430 , and 440 are filled and flowed, cooling passages may be formed on the edge surfaces 110a , 110b , 110c , and 110d of the battery cell 110 as a result. Since the edge surfaces 110a, 110b, 110c, and 110d of the battery cell 110 have high thermal conductivity of the battery cell 110, the insulating oil I is in direct contact with the edge surfaces 110a, 110b, 110c, and 110d. By flowing, the cooling performance of the battery cells 110 may be improved.
[53]
In addition, according to an embodiment of the present invention, by contacting the insulating oil (I) only through the edge surfaces (110a, 110b, 110c, 110d) without contacting the insulating oil (I) to the flat surfaces (110e, 110f), the battery By directly contacting 4 of the 6 sides of the battery cell 110 through the edge surfaces 110a, 110b, 110c, and 110d, which occupies only about 10% of the area of ​​the cell 110, the insulating oil (I) It is possible to minimize the use of the cooling system and at the same time improve the cooling efficiency.
[54]
In addition, by using the insulating oil (I), the conventional configuration of a thermal resin, a thermal pad, a heat sink, etc. is no longer required, so that the thermal resistance of each component is reduced, and it is possible to reduce the weight and compact the battery module. In addition, it is possible to prevent in advance the risk of a defective air layer between the interfaces during the process of attaching the thermal resin and thermal pad, and it is also possible to prevent in advance the internal short circuit of the battery module due to leakage of coolant in the event of a vehicle accident in which the battery module is installed. .
[55]
Hereinafter, the flow of insulating oil through the supply unit and the discharge unit according to an embodiment of the present invention will be described with reference to FIGS. 7 to 9 .
[56]
7 is a view showing a supply unit and a discharge unit according to an embodiment of the present invention. 8 is a view showing the flow of insulating oil according to an embodiment of the present invention. 9 is a view showing a connection flow path between battery modules according to an embodiment of the present invention.
[57]
7 and 8 , a supply unit 500 to which insulating oil I is supplied may be formed on the upper end of the first end plate 310 according to an embodiment of the present invention, and the second end plate 320 may be formed. ) may be formed at the lower end of the discharge unit 600 through which the insulating oil (I) is discharged. Accordingly, the insulating oil I supplied to the supply unit 500 may flow from the first space portion 410 , through the second space portion 420 or the third space portion 430 , to the fourth space portion 440 . can The insulating oil I flowing into the fourth space 440 may be discharged to the outside of the battery module through the discharge unit 600 .
[58]
The supply unit 500 and the discharge unit 600 formed in each battery module may be connected to each other through a connection flow path 700 . According to an embodiment of the present invention, the connection flow path 700 may be formed of a hose, but is not limited thereto, and is formed of a material that minimizes the flow resistance of the insulating oil (I) to stably supply the insulating oil (I). it is enough to have
[59]
According to an embodiment of the present invention, the supply unit 500 may be formed at the upper end of the first end plate 310 , and the discharge unit 600 may be formed at the lower end of the second end plate 320 . By positioning the supply unit 500 above the discharge unit 600 as described above, the insulating oil (I) is stably applied to the battery module in consideration of the difference in resistance between the flow path resistance inside the module and the connection flow path 700 connecting between the battery modules. can supply
[60]
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 or voltage of the battery and a cooling device are added and packed.
[61]
The battery pack may be applied to various devices. Such a device may be applied to transportation means such as an electric bicycle, an electric vehicle, and a hybrid vehicle, 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 .
[62]
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 may be made 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.
[63]
Explanation of symbols
[64]
100: battery cell stack
[65]
110: battery cell
[66]
110a, 110b, 110c, 110d: edge surface
[67]
110e, 110f: flat surface
[68]
120: electrode lead
[69]
130: bus bar frame
[70]
200: frame
[71]
210: upper surface of the frame
[72]
220: when the frame
[73]
300: end plate
[74]
310: first end plate
[75]
320: second end plate
[76]
400: space part
[77]
410: first space unit
[78]
420: second space portion
[79]
430: third space part
[80]
440: fourth space unit
[81]
500: supply
[82]
600: discharge unit
[83]
700: connection euro
[84]
I: insulating oil

WE CLAIMS

a battery cell stack in which battery cells formed of an edge surface and a flat surface are stacked; electrode leads protruding from the battery cells; a frame formed of upper, lower, left, and right surfaces to cover the upper, lower, left, and right surfaces of the battery cell stack; and an end plate covering the front and rear surfaces of the battery cell stack, wherein a space is formed between the edge surfaces of the battery cells, the frame and the end plate, and the plurality of battery cells are formed in the space. A battery module in which an insulating oil for cooling is filled and flows, and the insulating oil is in contact with the battery cell and the electrode leads.
[Claim 2]
According to claim 1, wherein the space portion, A first space formed between the edge surfaces of the battery cells formed on the front surface of the battery cell stack and a first end plate covering the front surface of the battery cell stack; a second space formed between the edge surfaces of the battery cells formed on the upper side of the battery cell stack and the upper surface of the frame; a third space formed between the edge surfaces of the battery cells formed on the lower side of the battery cell stack and the lower surface of the frame; and a fourth space formed between the edge surfaces of the battery cells formed on the rear surface of the battery cell stack and a second end plate that covers the rear surface of the battery cell stack.
[Claim 3]
The battery module of claim 2, wherein the first and fourth space portions are formed in a space between the end plate and the edge surfaces formed in two battery cells adjacent to each other.
[Claim 4]
The battery module of claim 2, wherein the second and third space portions are formed in a space between the frame and the edge surfaces formed in two battery cells adjacent to each other.
[Claim 5]
The battery module of claim 2 , wherein the insulating oil flows from the first space portion of the battery cell stack, through the second space portion or the third space portion, to the fourth space portion.
[Claim 6]
The battery module of claim 2 , wherein a supply unit to which the insulating oil is supplied is formed at an upper end of the first end plate, and a discharge unit through which the insulating oil is discharged is formed at a lower end of the second end plate.
[Claim 7]
The battery module of claim 2 , wherein the electrode leads protrude from both ends of the battery cells into the first and fourth spaces, respectively, and contact the insulating oil flowing in the first and fourth spaces.
[Claim 8]
The battery module of claim 1 , wherein the end plate and the frame are coupled with an adhesive, and the end plate and the frame are sealed with the adhesive.
[Claim 9]
The battery module of claim 1, further comprising a bus bar frame formed between the end plate and the battery cell stack, wherein the bus bar frame is positioned on the space portion and is in contact with the insulating oil.
[Claim 10]
A battery pack comprising the battery module according to claim 1 .