[One]Cross-Citation with Related Application(s)
[2]This application claims the benefit of priority based on Korean Patent Application No. 10-2019-0056449 dated May 14, 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 for solving a stability problem caused by a chain reaction caused by high temperature heat, and a battery pack including the same.
background
[4]
Secondary batteries, which are easy to apply according to product groups and have electrical characteristics such as high energy density, are universally applied to electric vehicles or hybrid vehicles driven by an electric drive source, as well as portable devices, and power storage devices. These secondary batteries are attracting attention as a new energy source for improving eco-friendliness and energy efficiency in that not only the primary advantage of being able to dramatically reduce the use of fossil fuels, but also the fact that no by-products are generated from the use of energy.
[5]
The battery pack applied to the battery vehicle has a structure in which a plurality of cell assemblies including a plurality of unit cells are connected in series to obtain high output. In addition, the unit cell can be repeatedly charged and discharged by an electrochemical reaction between components, including positive and negative current collectors, separators, active materials, electrolytes, and the like.
[6]
On the other hand, in recent years, as the need for a large-capacity structure, including its use 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 connected in series and/or in parallel is increasing. .
[7]
On the other hand, when configuring a battery pack by connecting a plurality of battery cells in series/parallel, a battery module including at least one battery cell is first configured, and other components are added using the at least one battery module to form a battery. The way the pack is structured is common.
[8]
Since various combustible materials are embedded in the secondary battery, there is a risk of heat generation and explosion due to overcharging, overcurrent, and other physical external shocks, and thus has a major disadvantage in safety. Therefore, in the case of a battery module or battery pack including a plurality of such secondary batteries, a battery management system (BMS) is sometimes used to safely and efficiently manage the batteries.
[9]
However, despite this method, there are cases in which a fire occurs inside the battery pack due to an external shock, abnormal operation of the internal battery cell, control failure by BMS, or the like. When a fire occurs in one battery cell inside a battery pack and a fire occurs in a chain that affects adjacent battery cells, damage to life and property may increase. Accordingly, structurally, it is necessary to develop a technology for a safety device.
DETAILED DESCRIPTION OF THE INVENTION
technical challenge
[10]
SUMMARY OF THE INVENTION An object of the present invention is to provide a battery module and a battery pack including the same for preventing a chain action caused by ejection of high-temperature and high-pressure gas from a battery cell by sufficiently utilizing the space between the cooling passages.
[11]
However, the problems to be solved by the embodiments of the present invention are not limited to the above-described problems and may be variously expanded within the scope of the technical idea included in the present invention.
means of solving the problem
[12]
A battery module according to an embodiment of the present invention includes a battery cell stack in which a plurality of battery cells are stacked, and a heat sink positioned at one side of the battery cell stack, wherein the heat sink includes a cooling pipe, at least one of the rupture and sealing material layer.
[13]
The at least one rupture part may include a first rupture part and a second rupture part, the first rupture part may be located at one end of the heat sink, and the second rupture part may be located at the other end of the heat sink.
[14]
The heat sink is elongated in a direction perpendicular to the stacking direction of the battery cell stack, the first rupture part is located at one end in the direction in which the heat sink extends, and the second rupture part is the other in the direction in which the heat sink extends. can be located at one time.
[15]
The heat sink may include at least one protrusion protruding in the direction of the battery cell stack, and an ejection hole is formed in the protrusion, and the ejection hole may be filled with a sealing material formed in the sealing material layer extending therefrom.
[16]
The first rupture part and the second rupture part may be formed at distal ends of the protrusion part.
[17]
The battery module may further include a resin layer positioned between the heat sink and the battery cell stack.
[18]
The resin layer may be formed in plural spaced apart from each other, and the protrusion may be positioned between the plurality of resin layers.
[19]
The battery module may further include a compression pad positioned between the plurality of battery cells, and the compression pad may be positioned to correspond to the protrusion.
[20]
Each of the first rupture part and the second rupture part may have a dome shape protruding in different directions with respect to the bottom surface of the heat sink.
[21]
The sealing material layer is continuously formed from the first rupture part to the second rupture part, and the cross-sectional area of ​​the sealing material layer may gradually increase from the first rupture part to the second rupture part.
[22]
The first rupture part may have a dome shape protruding upward with respect to the bottom surface of the heat sink, and the second rupture part may have a dome shape protruding downward with respect to the bottom surface of the heat sink.
[23]
The battery module may further include a third rupture part positioned on the upper surface of the heat sink.
[24]
The first rupture part is destroyed as the internal pressure of the battery cell stack increases, and the second rupture part is destroyed while the generated internal pressure pushes the sealing material located in the sealing material layer, and the internal pressure of the remaining gas causes the As the third rupture portion is destroyed, gas may be ejected.
[25]
The sealing material layer may include a fire extinguishing gel or an insulating oil.
[26]
A battery pack according to another embodiment of the present invention includes the battery module.
Effects of the Invention
[27]
According to the embodiments, when gas ejection by fire occurs in the battery cell, the rupture part is destroyed due to an increase in internal pressure due to this, and a battery cell sealing material is ejected through the rupture part to prevent a chain reaction by blocking high-temperature heat can do.
[28]
In addition, by forming an additional rupture portion on the outer surface of the heat sink, it is possible to reduce the possibility of explosion due to generation of a large amount of gas due to the chain ignition of the battery by the high-temperature gas.
[29]
In addition, since the heat sink is not only a device for cooling, but also includes a safety device, space can be used compactly.
Brief description of the drawing
[30]
1 is a perspective view showing a battery module according to an embodiment of the present invention.
[31]
FIG. 2 is a cross-sectional view taken along line II-II' of FIG. 1 .
[32]
3 is a perspective view of a battery module according to an embodiment of the present invention as viewed in the direction A of FIG. 1 .
[33]
4 is a perspective view of the battery module according to an embodiment of the present invention as viewed in the direction B of FIG. 1 .
[34]
5 is a cross-sectional view of the battery module according to an embodiment of the present invention, which crosses a space filled with a battery cell sealing material along the direction B of FIG. 1 .
[35]
6 shows an inverted dome-shaped rupture part according to an embodiment of the present invention.
[36]
7 is a graph illustrating a process in which gas is ejected as internal pressure increases in the battery module according to an embodiment of the present invention.
Modes for carrying out the invention
[37]
Hereinafter, with reference to the accompanying drawings, various embodiments of the present invention will be described in detail so that those of ordinary skill in the art can easily carry out the present invention. The present invention may be embodied in many different forms and is not limited to the embodiments described herein.
[38]
In order to clearly explain the present invention, parts irrelevant to the description are omitted, and the same reference numerals are assigned to the same or similar elements throughout the specification.
[39]
In addition, since the size and thickness of each component shown in the drawings are arbitrarily indicated for convenience of description, the present invention is not necessarily limited to the illustrated bar. In order to clearly express various layers and regions in the drawings, the thicknesses are enlarged. And in the drawings, for convenience of description, the thickness of some layers and regions are exaggerated.
[40]
Also, when a part of a layer, film, region, plate, etc. is said to be “on” or “on” another part, it includes not only cases where it is “directly on” another part, but also cases where there is another part in between. . Conversely, when we say that a part is "just above" another part, we mean that there is no other part in the middle. In addition, to be "on" or "on" the reference portion means to be located above or below the reference portion, and to necessarily mean to be located "on" or "on" in the direction opposite to the gravity no.
[41]
In addition, throughout the specification, when a part "includes" a certain component, this means that other components may be further included, rather than excluding other components, unless otherwise stated.
[42]
In addition, throughout the specification, when "on a plane", it means when the target part is viewed from above, and when "in cross-section", it means when viewed from the side of a cross-section obtained by cutting the target part vertically.
[43]
1 is a perspective view showing a battery module according to an embodiment of the present invention. FIG. 2 is a cross-sectional view taken along line II-II' of FIG. 1 .
[44]
1 and 2, the battery module according to this embodiment is a battery cell stack 100 in which a plurality of battery cells 110 are stacked in one direction, located at one side of the battery cell stack 100 A heat sink 300 and a side plate 180 adjacent to the battery cell 110 positioned at the outermost side in the stacking direction of the battery cell stack 100 are included. The heat sink 300 is positioned on the battery cell stack 100 , and may extend long along one side of the battery cell 110 , not along a portion where the battery cell 110 is connected to an electrode lead (not shown). Although not shown, the end plate may be coupled in the A direction and the B direction in FIG. 1 .
[45]
The heat sink 300 according to the present embodiment includes a cooling pipe 310 , at least one rupture portion 210 , 230 , and a sealing material layer 250 . The sealing material layer 250 may include fire extinguishing gel or insulating oil. Digestive gel or insulating oil can prevent an internal short circuit in the secondary battery and dissipate high-temperature heat, and a liquid that can seal the periphery of the battery cell 110 can be used.
[46]
Referring to FIG. 2 , the battery cell stack 100 may further include a compression pad 130 formed between the plurality of battery cells 110 . The compression pad 130 may function to absorb a change in volume and a dimensional tolerance of the battery cell itself according to the characteristics that the battery cell 110 expands/contracts according to the state of charge. The resin layer 150 may be positioned between the battery cell stack 100 and the heat sink 300 . The resin layer 150 may transfer heat generated in the battery cell stack 100 to the heat sink 300 . Thereafter, heat is transferred to the cooling pipe 310 through which the cooling water flows, so that the heat generated in the battery cell stack 100 may be cooled. The cooling pipe 310 may extend long in a bar shape in a direction perpendicular to the stacking direction of the battery cell stack 100 . A plurality of resin layers 150 may be formed to be spaced apart from each other, and a protrusion 300p may be positioned between the plurality of resin layers 150 . The protrusion 300p may be positioned to correspond to the compression pad 130 .
[47]
In the heat sink 300 according to the present embodiment, a sealing material layer 250 made of a sealing material is formed therein, and a cooling pipe 310 through which cooling water passes is formed around the sealing material layer 250 . . The heat sink 300 may extend in a direction perpendicular to the stacking direction of the battery cell stack 100 . The sealing material layer 250 may be formed by forming an elongated hole 250h inside the heat sink 300 and filling the sealing material into the hole 250h.
[48]
At least one protrusion 300p protruding in a direction in which the battery cell stack 100 is positioned may be formed at the lower end of the heat sink 300 . The protrusion 300p has a structure in which a portion of the heat sink 300 protrudes toward the battery cell stack 100 , and may be integrally formed with the heat sink 300 . The ejection hole 300h is formed in the protrusion 300p, and the sealing material formed in the sealing material layer 250 may extend and fill the ejection hole 300h. In other words, the ejection hole 300h may extend with the hole 250h in which the sealing material layer 250 is formed, and the sealing material filled in the ejection hole 300h may be connected to the sealing material layer 250 .
[49]
Hereinafter, the rupture part according to the present embodiment will be described in detail with reference to FIGS. 3 and 4 .
[50]
3 is a perspective view of a battery module according to an embodiment of the present invention as viewed in the direction A of FIG. 1 . 4 is a perspective view of the battery module according to an embodiment of the present invention as viewed in the direction B of FIG. 1 .
[51]
Referring to FIG. 3 , there may be at least one rupture part according to the present embodiment, and for example, two first rupture parts 210 may be formed to be spaced apart from each other along the stacking direction of the plurality of battery cells 110 . have. The first rupture part 210 may be located at one end of the heat sink 300 . The rupture part according to the present embodiment may include a second rupture part 220 as shown in FIG. 4 in addition to the first rupture part 210 . The second rupture part 220 may be positioned at the other end of the heat sink 300 to correspond to one end of the heat sink 300 where the first rupture part 210 is positioned. Specifically, when the heat sink 300 extends in a direction perpendicular to the stacking direction of the battery cell stack 100 , the first rupture part 210 is located at one end in the direction in which the heat sink 300 extends, The second rupture part 220 may be located at the other end in the direction in which the heat sink 300 extends.
[52]
The first rupture part 210 and the second rupture part 220 according to the present embodiment are at the ends of the protrusion part 300p, which is a structure in which a part of the heat sink 300 protrudes in the direction of the battery cell stack 100 . can be formed. An ejection hole 300h filled with a sealing material is formed inside the distal end of the protrusion 300p. In this case, the first rupture part 210 and the second rupture part 220 may have a dome shape or a valve shape protruding in different directions with respect to the bottom surface of the heat sink 300 . The battery module according to this embodiment has the structure as described above, and when gas is generated due to fire in the battery cell 110 , the internal pressure is increased to increase the first rupture part 210 and the second rupture part 220 . ) is destroyed, and the sealing material of the sealing material layer 250 is ejected to block the battery cell 110 . That is, it is possible to prevent a chain reaction by blocking the transfer of high-temperature heat to the other battery cells 110 adjacent to the battery cell 110 in which the fire has occurred.
[53]
5 is a cross-sectional view of the battery module according to an embodiment of the present invention, which crosses a space filled with a battery cell sealing material along the direction B of FIG. 1 .
[54]
Referring to FIG. 5 , the sealing material layer 250 according to the present embodiment is continuously formed from the first rupture part 210 to the second rupture part 220 , and the cross-sectional area of ​​the sealing material layer 250 is the first From the rupture part 210 to the second rupture part 220, it may gradually become wider. Here, the cross-sectional area of ​​the sealing material layer 250 may represent a portion cut in a plane perpendicular to the stacking direction of the battery cell stack 100 . As described above, the first rupture part 210 and the second rupture part 220 are destroyed to eject the sealing material of the sealing material layer 250 to block the battery cell 110, When the first rupture part 210 is destroyed, the sealing material constituting the sealing material layer 250 is pushed out, and the internal pressure of the sealing material layer 250 increases, so that the second rupture part 220 is destroyed. At this time, in order to have a direction in which the sealing material of the sealing material layer 250 is ejected, the rupture parts 210 and 220 have a dome shape protruding in different directions with respect to the bottom surface of the heat sink 300 . desirable. Since the rupture parts 210 and 220 have a dome-shaped destruction direction, the first rupture part 210 has a dome shape protruding downward based on the bottom surface of the heat sink 300 based on the inverted dome shape, 2 The rupture part 220 may have a dome shape protruding upward with respect to the bottom surface of the heat sink 300 . Specifically, the dome shape according to this embodiment may be an inverted dome in which the protruding directions are opposite before and after the operation, as shown in FIG. 6 as an example of such an inverted dome-shaped rupture part.
[55]
6 shows an inverted dome-shaped rupture part according to an embodiment of the present invention.
[56]
Referring to FIG. 6 , FIG. 6A shows a state before the rupture disk operates, and FIG. 6B shows a state after the rupture disk operates. The rupturable discs 210 and 220 according to the present embodiment described with reference to FIG. 5 may include support parts 210a and 220a and wing parts 210b and 220b that can be opened according to gas generation inside the support parts 210a and 220a. have. In a normal state, the rupture disks 210 and 220 of FIG. 5 have the wings 210b and 220b closed as in FIG. 6A , and when a predetermined pressure is applied due to the generation of high-temperature gas, the wings 210b and 220b are torn, It can be opened as in Figure 6b.
[57]
In this way, the sealing material may be ejected to the second rupture part 220 and circulate. As described above, since the sealing material layer 250 has a structure in which the cross-sectional area of ​​the sealing material layer 250 gradually increases from the first rupture part 210 to the second rupture part 220 , the flow of the sealing material may be induced. For example, such a cross-sectional structure is preferable because when pushing a certain fluid from a narrow area to a wide area requires less force.
[58]
As described above, the battery module according to the present embodiment has a structure including the first rupture part 210 and the second rupture part 220 , so that the battery cell sealing material is ejected through the rupture part to generate high-temperature heat. can be blocked. In addition to these effects, by including additional rupture parts in addition to the rupture parts 210 and 220 described in the present embodiment, the possibility of explosion due to high pressure can be reduced. In this regard, referring to FIGS. 1, 2 and 5 , the battery module may further include a third rupture part 230 positioned on the upper surface of the heat sink 300 .
[59]
In the third rupture part 230 according to the present embodiment, the first rupture part 210 is destroyed as the internal pressure of the battery cell stack 100 increases, and the generated internal pressure is a sealing material located in the sealing material layer 250 . After the second rupture part 220 is destroyed while pushing the have.
[60]
7 is a graph illustrating a process in which gas is ejected as internal pressure increases in the battery module according to an embodiment of the present invention.
[61]
Referring to FIG. 7 , as the time value (minutes) on the horizontal axis gradually increases, the primary rupture occurs at the first rupture, and then, as described above, the generated internal pressure pushes the sealing material of the sealing material layer and the second rupture It can be seen that the secondary rupture occurs in the part, and after the tertiary rupture occurs in the third rupture part due to the internal pressure of the remaining gas, the internal pressure of the battery cell is finally stabilized. In other words, in the upper graph, the vertical axis represents the amount of gas generated by the battery cell, and in the lower graph, the vertical axis represents the pressure change in the battery module due to gas generation, and the pressure inside the battery module as the gas is ejected to the outside at the time of the third rupture. You can see it drop.
[62]
Meanwhile, one or more battery modules according to an embodiment of the present invention may be packaged in a pack case to form a battery pack.
[63]
The above-described battery module and battery pack including the same 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 is applicable to various devices that can use a battery module and a battery pack including the same, and this It belongs to the scope of the invention.
[64]
Although preferred embodiments of the present invention have been described in detail above, the scope of the present invention is not limited thereto, and various modifications and improvements by those skilled in the art using the basic concept of the present invention as defined in the following claims are also provided. is within the scope of the
[65]
Explanation of symbols
[66]
210, 220, 230: rupture part
[67]
250: sealing material layer
[68]
300p: overhang
[69]
300: heat sink

WE CLAIM

[Claim 1]A battery comprising a battery cell stack in which a plurality of battery cells are stacked, and a heat sink positioned at one side of the battery cell stack, wherein the heat sink includes a cooling pipe, at least one rupture part, and a sealing material layer module.
[Claim 2]
The method of claim 1, wherein the at least one rupture part includes a first rupture part and a second rupture part, wherein the first rupture part is located at one end of the heat sink, and the second rupture part is located at the other end of the heat sink. battery module.
[Claim 3]
The heat sink of claim 2 , wherein the heat sink extends in a direction perpendicular to the stacking direction of the battery cell stack, the first rupture part is located at one end in the direction in which the heat sink extends, and the second rupture part extends to the heat sink A battery module located at the other end of the extending direction.
[Claim 4]
The heat sink of claim 3, wherein the heat sink includes at least one protrusion protruding in the direction of the battery cell stack, and an ejection hole is formed in the protrusion, and a sealing material formed in the sealing material layer extends through the ejection hole. A battery module that is fully loaded.
[Claim 5]
The battery module of claim 4 , wherein the first rupture part and the second rupture part are formed at distal ends of the protrusion part.
[Claim 6]
The battery module of claim 4, further comprising a resin layer positioned between the heat sink and the battery cell stack.
[Claim 7]
The battery module of claim 6 , wherein a plurality of the resin layers are formed to be spaced apart from each other, and the protrusion is positioned between the plurality of resin layers.
[Claim 8]
The battery module of claim 4, further comprising a compression pad positioned between the plurality of battery cells, wherein the compression pad is positioned to correspond to the protrusion.
[Claim 9]
The battery module of claim 2 , wherein the first rupture part and the second rupture part each have a dome shape protruding in different directions with respect to a bottom surface of the heat sink.
[Claim 10]
The battery of claim 2, wherein the sealing material layer is continuously formed from the first rupture part to the second rupture part, and the cross-sectional area of ​​the sealing material layer gradually increases from the first rupture part to the second rupture part. module.
[Claim 11]
The battery of claim 10 , wherein the first rupture part has a dome shape protruding upward with respect to the bottom surface of the heat sink, and the second rupture part has a dome shape protruding downward with respect to the bottom surface of the heat sink. module.
[Claim 12]
The battery module of claim 10 , further comprising a third rupture part positioned on an upper surface of the heat sink.
[Claim 13]
The method of claim 12, wherein the first rupture part is destroyed as the internal pressure of the battery cell stack increases, and the second rupture part is destroyed while the generated internal pressure pushes the sealing material located in the sealing material layer, and the remaining gas A battery module in which gas is ejected while the third rupture part is destroyed by internal pressure.
[Claim 14]
The battery module of claim 1, wherein the sealing material layer includes a fire extinguishing gel or an insulating oil.
[Claim 15]
A battery pack comprising the battery module according to claim 1 .