Battery pack and vehicle including said battery pack

Abstract

A battery pack according to one embodiment of the present invention is characterized by including a plurality of cell assemblies including one or more battery cells and arranged in at least one row, a pack case that houses the plurality of cell assemblies, and a partition member that partitions the plurality of cell assemblies within the pack case, is made of a flexible material, and tightly surrounds the plurality of cell assemblies.

Description

[Technical field]

[0001] The present invention relates to a battery pack and a vehicle including the battery pack, and more particularly to a battery pack having improved safety against thermal events and a vehicle including the battery pack.

[0002] This application claims priority to Korean Patent Application No. 10-2022-0183383 filed on December 23, 2022, and Korean Patent Application No. 10-2023-0043172 filed on March 31, 2023, the entire contents of which are incorporated herein by reference in their entirety in the specification and drawings. [Background technology]

[0003] Secondary batteries, which are easily applicable to various products and have electrical properties such as high energy density, are widely used not only in portable devices but also in electric vehicles (EVs) and hybrid electric vehicles (HEVs) that are driven by electric sources. These secondary batteries have the main advantage of dramatically reducing the use of fossil fuels, as well as the advantage of not producing any by-products from the use of energy, and are therefore drawing attention as a new energy source that is environmentally friendly and improves energy efficiency.

[0004] Currently widely used types of secondary batteries include lithium ion batteries, lithium polymer batteries, nickel cadmium batteries, nickel metal hydride batteries, and nickel zinc batteries. The operating voltage of such a unit secondary battery cell, i.e., a unit battery cell, is about 2.5V to 4.5V. Therefore, when a higher output voltage is required, a battery pack may be configured by connecting a plurality of battery cells in series. Also, a battery pack may be configured by connecting a plurality of battery cells in parallel depending on the charge / discharge capacity required for the battery pack. Therefore, the number of battery cells included in the battery pack may be variously set depending on the required output voltage or charge / discharge capacity.

[0005] Meanwhile, when configuring a battery pack by connecting a plurality of battery cells in series / parallel, a common method is to first configure a battery module including at least one battery cell, and then use this at least one battery module to add other components to configure a battery pack or a battery rack.

[0006] However, when multiple secondary batteries (battery cells) or multiple battery modules are densely packed in a small space, they may be vulnerable to thermal events. In particular, if an event such as thermal runaway occurs in any battery cell, high-temperature gas, flames, heat, etc. may be generated. If such gas, flames, heat, etc. are transmitted to other battery cells included in the same battery module, an explosive chain reaction situation such as thermal propagation may occur. Furthermore, such a chain reaction may not only cause accidents such as fire or explosion in the battery module, but may also cause fire or explosion in other battery modules.

[0007] Furthermore, in the case of medium to large battery packs such as electric vehicles, the risk of thermal chain reactions may be further increased since a large number of battery cells and battery modules are included to increase the output and / or capacity. In addition, in the case of battery packs mounted on electric vehicles, users such as drivers may be present in the vicinity. Therefore, if a thermal event occurring in a particular battery module cannot be appropriately controlled and a chain reaction occurs, it may cause not only serious property damage but also loss of human life.

[0008] Therefore, if a thermal runaway occurs due to a thermal event at the battery module level within the battery pack, it is important that ejected materials such as high-temperature gas, flames, and particles are quickly exhausted from the battery pack to prevent greater risks such as secondary fires and explosions due to an increase in the internal pressure of the battery pack.

[0009] However, in a battery pack, the mechanisms for housing the battery modules and the structures for partitioning other battery modules in the battery pack are made of aluminum materials to ensure rigidity, and many of them melt at about 600 degrees Celsius. Particles generated by the melting of such structures during a thermal event can collapse the mechanisms of the battery modules and the structures for partitioning other battery modules in the battery pack, or block the discharge part of the vent unit of the battery pack, increasing the internal pressure of the battery pack and becoming an important factor in causing greater damage such as the secondary fire or explosion of the battery pack described above.

[0010] Furthermore, in the case of conventional battery packs, there is a problem that high-temperature gases, flames, particles, and other ejections generated during a thermal event flow into gap spaces generated by assembly tolerances between components that make up the above-mentioned battery module mechanisms and structures that separate the battery modules, accelerating the collapse of the above-mentioned mechanisms and structures such as vent units.

[0011] Therefore, there is a need to find a way to provide a battery pack and a vehicle including the battery pack that can solve the above problems and improve safety against thermal events. Summary of the Invention [Problem to be solved by the invention]

[0012] Therefore, an object of the present invention is to provide a battery pack that can improve safety against thermal events, and a vehicle including the battery pack.

[0013] Another object of the present invention is to provide a battery pack that can be slimmed down and have improved energy efficiency, and a vehicle including the battery pack.

[0014] However, the technical problems that the present invention aims to solve 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 description of the invention described below. [Means for solving the problem]

[0015] In order to achieve the above object, the present invention provides a battery pack comprising: a plurality of cell assemblies including one or more battery cells and arranged in at least one row; a pack case accommodating the plurality of cell assemblies; and a partition member that partitions the plurality of cell assemblies within the pack case, is made of a flexible material, and tightly surrounds the plurality of cell assemblies.

[0016] Also, desirably, the partition member can be in close contact with side surfaces of the plurality of cell assemblies in the arrangement direction of the plurality of cell assemblies.

[0017] Also preferably, the partition member is made of a fire-resistant rubber material.

[0018] Also, preferably, the partition member is made of an insulating rubber material.

[0019] Also, desirably, the partition member can be disposed between the plurality of cell assemblies in the arrangement direction of the plurality of cell assemblies.

[0020] Also, preferably, a plurality of the partition members are provided corresponding to the number of the plurality of cell assemblies, and the plurality of partition members can be closely attached to both side surfaces of each of the cell assemblies.

[0021] Also, preferably, the partition members may be disposed at predetermined distances from each other in the arrangement direction of the cell assemblies.

[0022] Also, preferably, a vent portion may be provided at a lower portion of the one or more battery cells, and the partition member may surround a side portion of the plurality of cell assemblies with the vent portion exposed.

[0023] Also, preferably, the bottom of the pack case faces the vent portion and breaks or melts when gas or flame is discharged through the vent portion, thereby enabling the gas or flame to be discharged to the outside of the pack case.

[0024] Also, preferably, the pack case includes a case body supporting the multiple cell assemblies and the partition member, and a case cover coupled to the case body and housing the multiple cell assemblies and the partition member, the bottom of the case body facing the vent portion and capable of being broken or melted so as to allow the gas or flame to be discharged to the outside of the pack case when the gas or flame is discharged through the vent portion.

[0025] Also, preferably, the battery pack may include a potting resin filled in a space between the plurality of cell assemblies and the case cover.

[0026] Also, desirably, the potting resin may fill spaces between the plurality of cell assemblies.

[0027] The present invention also provides a vehicle, characterized in that it includes a battery pack according to the above-described embodiment. Effect of the Invention

[0028] According to the various embodiments described above, it is possible to provide a battery pack capable of improving safety against thermal events, and a vehicle including the battery pack.

[0029] Furthermore, according to the various embodiments as described above, it is possible to provide a battery pack that can be slimmed down and have improved energy efficiency, and a vehicle including the battery pack.

[0030] In addition, the present invention can have various other effects, which will be described in each embodiment, or the description of effects that can be easily inferred by those skilled in the art will be omitted.

[0031] The following drawings attached to this specification illustrate preferred embodiments of the present invention and, together with the detailed description of the invention, serve to further understand the technical ideas of the present invention. Therefore, the present invention should not be interpreted as being limited only to the matters described in the drawings. [Brief description of the drawings]

[0032] [Figure 1] 1 is a diagram illustrating a battery pack according to an embodiment of the present invention; [Diagram 2] 2 is a diagram for explaining a partition member surrounding the cell assembly of the battery pack of FIG. 1. FIG. [Diagram 3] 2 is a diagram for explaining a partition member surrounding the cell assembly of the battery pack of FIG. 1. FIG. [Figure 4]FIG. 2 is a diagram for explaining a vent mechanism in the battery pack of FIG. 1 during a thermal event. [Diagram 5] 11 is a diagram illustrating a battery pack according to another embodiment of the present invention. FIG. [Figure 6] FIG. 6 is a diagram for explaining a vent mechanism during a thermal event in the battery pack of FIG. 5. [Figure 7] 11 is a diagram illustrating a battery pack according to still another embodiment of the present invention. [Figure 8] 11 is a diagram illustrating a battery pack according to still another embodiment of the present invention. [Figure 9] 11 is a diagram illustrating a battery pack according to still another embodiment of the present invention. [Figure 10] FIG. 10 is a diagram for explaining a vent mechanism in the battery pack of FIG. 9 during a thermal event. [Figure 11] 1 is a diagram for explaining an automobile according to an embodiment of the present invention; DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0033] Hereinafter, a preferred embodiment of the present invention will be described in detail with reference to the attached drawings. Prior to this, the terms and words used in the present specification and claims are not to be construed as being limited to their ordinary and dictionary meanings, but are to be construed as having meanings and concepts according to the technical ideas of the present invention, in accordance with the principle that the inventors themselves can appropriately define the concepts of terms in order to best describe the invention.

[0034] Therefore, it should be understood that the configurations shown in the embodiments described in this specification are merely the most preferred embodiments of the present invention and do not represent the entire technical idea of ​​the present invention, and therefore there may be various equivalents and modifications that can be substituted therefor at the time of this application.

[0035] Meanwhile, although terms indicating directions such as up, down, left, right, front, and back may be used in this specification, it will be obvious to those skilled in the art of the present invention that such terms are used for convenience of explanation and may vary depending on the position of the target object, the position of the observer, etc.

[0036] FIG. 1 is a diagram for explaining a battery pack 10 according to one embodiment of the present invention, and FIGS. 2 and 3 are diagrams for explaining a partition member 300 surrounding a cell assembly 100 of the battery pack 10 of FIG.

[0037] 1 to 3 , a battery pack 10 may include a cell assembly 100, a pack case 200, and a compartment member 300.

[0038] The cell assembly 100 may include one or more battery cells 110. In the present embodiment, the cell assembly 100 is limited to including a plurality of battery cells 110 in order to increase the output and / or capacity of the battery pack 10.

[0039] The battery cells 110 are secondary batteries and may be provided as pouch-type secondary batteries. The battery cells 110 may be stacked on one another so as to be electrically connected to one another. Meanwhile, in the present embodiment, the battery cells 110 are described as being provided as pouch-type secondary batteries only, but it goes without saying that the cell assembly may be provided as a mutual stack of cylindrical or prismatic secondary batteries other than the pouch-type secondary batteries.

[0040] A plurality of the cell assemblies 100 may be provided and arranged in at least one row. The arrangement of the plurality of cell assemblies 100 may vary depending on the required capacity, size, shape, etc. of the battery pack 10, and may be arranged in two or more rows or in a matrix shape. Hereinafter, in one embodiment of the present invention, the description will be limited to the case where the plurality of cell assemblies 100 are arranged in a row along the longitudinal direction (X-axis direction) of the battery pack 10.

[0041] The pack case 200 may accommodate the plurality of cell assemblies 100. To this end, the pack case 200 may be provided with an accommodating space capable of accommodating the plurality of cell assemblies 100. A specific structure of the pack case 200 will be discussed in more detail in the following related description.

[0042] The partition member 300 can partition the plurality of cell assemblies 100 within the pack case 200. The partition member 300 can support the plurality of cell assemblies 100 while guiding the arrangement positions of the plurality of cell assemblies 100 within the pack case 200.

[0043] The partition member 300 is made of a flexible material and can closely surround the plurality of cell assemblies 100. Specifically, the partition member 300 can closely surround the outer surface of the plurality of cell assemblies 100. The partition member 300 can function as a housing for accommodating the plurality of cell assemblies 100.

[0044] Conventionally, in the case of a structure such as a module housing for accommodating the cell assembly 100, unlike the partition member 300, it is generally made of a metal material, generally an aluminum material, and is provided as a frame assembly having a considerable weight. Therefore, in the case of a conventional battery pack, it is generally configured to include a plurality of battery modules each composed of such a cell assembly and a module housing for accommodating these cell assemblies. However, in the case of a conventional battery pack, when a battery pack is configured with a battery module including a plurality of cell assemblies inside, in addition to high-temperature gas and flames, a large amount of particles due to the melting of the structure is also generated due to the melting of the structure due to the melting of the metal material structure such as the module housing (melts at about 600 degrees Celsius). Such excessive ejection of a large amount of particles causes a problem of collapsing the mechanisms constituting the battery module and the structures for partitioning the battery module in the battery pack.

[0045] In addition, excessive ejection of a large number of particles as described above may block the outlet of the vent unit for releasing gas or flames to the outside of the battery pack, increasing the pressure inside the battery pack and posing a greater risk of secondary fire or explosion of the battery pack in the event of a thermal event.

[0046] Furthermore, in the case of conventional frame assemblies such as module housings, it is impossible to avoid the occurrence of gap spaces due to assembly tolerances when assembling components or housing cell assemblies. If ejections such as high-temperature gas, flames, or particles flow into such gap spaces during the above-mentioned thermal event, it becomes more difficult to expel the ejections from within the battery pack, accelerating the breakdown of the battery pack's mechanisms.

[0047] In one embodiment of the present invention, the partition member 300, which is made of a flexible material and tightly surrounds the multiple cell assemblies 100, allows the multiple cell assemblies 100 to be housed and separated from each other within the pack case 200, instead of using a frame assembly such as a separate module housing for housing the cell assemblies 100 as in the conventional case.

[0048] Therefore, in one embodiment of the present invention, the partition member 300 made of the flexible material can reduce the amount of particles and other ejections generated by melting due to high-temperature gas or flame during a thermal event, unlike a conventional module housing made of a metal material, and can significantly reduce the risk of collapse of the structure inside the battery pack 10 or blocking of the vent path due to ejections such as particles generated by melting metal. Thus, in one embodiment of the present invention, the partition member 300 can minimize the risk of secondary damage that may occur when the thermal event occurs.

[0049] In addition, in one embodiment of the present invention, due to the partition member 300 being in close contact with the multiple cell assemblies 100, no gap space is generated between the multiple cell assemblies 100 and the partition member 300, thereby fundamentally preventing problems such as accumulation and retention of ejected material such as high-temperature gas, flames, and particles that may occur in the gap space during a thermal event.

[0050] Furthermore, in one embodiment of the present invention, the partition member 300 can omit a frame assembly such as a separate module housing made of a metal material having a considerable weight as in the conventional art, thereby making it possible to slim down the entire battery pack 10, reducing its weight and significantly improving its energy efficiency. In other words, the present invention can configure a so-called CTP (Cell To Pack) type battery pack 10, in which the partition member 300 omits the module housing.

[0051] Moreover, in one embodiment of the present invention, since the partition member 300 is formed of a flexible material, it goes without saying that assembly can be made easier when housing the cell assembly 100.

[0052] The partition member 300 according to an embodiment of the present invention will be discussed in more detail below.

[0053] The partition member 300 may be in close contact with the side surfaces of the plurality of cell assemblies 100 in the arrangement direction (X-axis direction) of the plurality of cell assemblies 100. In the case of a pouch-type secondary battery, cell expansion called cell swelling generally occurs when overheating or continuous charging and discharging occurs, and such cell swelling has the largest deformation amount at the side surfaces of the battery cells 110.

[0054] In one embodiment of the present invention, the partition member 300 is in close contact with the side surfaces of the plurality of cell assemblies 100, so that the cell expansion of the cell assemblies 100 during such cell swelling can be effectively controlled.

[0055] The partition member 300 may surround the cell assemblies 100 while closely contacting only their side surfaces. That is, the partition member 300 may have an accommodation space capable of accommodating the cell assemblies 100 therein, and may have openings exposing the upper and lower sides of the cell assemblies 100 in the vertical direction (Z-axis direction). For this purpose, the partition member 300 may be provided as a hollow structure having an opening exposed in the vertical direction (Z-axis direction). The cell assemblies 100 may be inserted so as to be disposed within the accommodation space inside the partition member 300 through the opening in the vertical direction (Z-axis direction) of the partition member 300.

[0056] Therefore, in this embodiment, it is possible to improve the convenience of the worker during the assembly process of the cell assembly 100 and the partition member 300. Also, in this embodiment, since the partition member 300 does not cover the upper and lower sides of the plurality of cell assemblies 100 in the vertical direction (Z-axis direction) of the cell assembly 100, the overall size of the battery pack 10 can be made slimmer in the vertical direction (Z-axis direction) of the battery pack 10.

[0057] At the opening side exposed at the lower side of the partition member 300, the bottoms of the battery cells 110 of the cell assemblies 100 may abut against a bottom plate 212 of a case body 210 of the pack case 200, which will be described later, or may be spaced apart by a predetermined distance. Meanwhile, a vent portion 115 for discharging internal gas during a thermal event is provided at the bottom of the battery cells 110 of the cell assemblies 100, which will be described in more detail in the related description below. As described above, the partition member 300 according to the present embodiment can solve the interference problem with the vent portion 115 of the battery cells 110 through an opening structure exposed in the vertical direction (Z-axis direction).

[0058] The partition member 300 may be made of a fire-resistant rubber material. For example, the partition member 300 may be made of a flexible fire-resistant rubber material that can maintain its shape for at least 5 minutes or more when heated at about 1300 degrees Celsius to ensure fire resistance.

[0059] In one embodiment of the present invention, the partition member 300 made of the fire-resistant rubber material is capable of withstanding high-temperature gases and flames for a considerable period of time without changing its shape during a thermal event, thereby slowing down the rate of heat propagation from the cell assembly 100 in which the thermal event occurred to the adjacent cell assembly 100 as much as possible, and significantly reducing the risk of large amounts of particles and other ejections due to melting.

[0060] The partition member 300 may be made of an insulating rubber material. In one embodiment of the present invention, the partition member 300 made of such an insulating material can ensure insulation performance, so that even if an electrical problem occurs in one of the cell assemblies 100, a short circuit or the like that may occur in a chain reaction in the adjacent cell assembly 100 can be effectively prevented.

[0061] The partition members 300 may be disposed between the cell assemblies 100 in the arrangement direction (X-axis direction) of the cell assemblies 100. Through such an arrangement structure of the partition members 300, the cell assemblies 100 are each partitioned and disposed within the pack case 200, and heat propagation to the adjacent cell assembly 100 when a thermal event occurs can be effectively delayed.

[0062] A plurality of the partition members 300 may be provided corresponding to the number of the cell assemblies 100. The partition members 300 may be closely attached to both side surfaces of each of the cell assemblies 100. Here, each of the partition members 300 may house one cell assembly 100. That is, each of the partition members 300 may house a respective cell assembly 100 and closely surround both side surfaces of the respective cell assembly 100.

[0063] In one embodiment of the present invention, the partition members 300 are provided in multiple numbers corresponding to the number of the cell assemblies 100, and house each of the cell assemblies 100, so that the multiple cell assemblies 100 can be more stably supported and the multiple cell assemblies 100 can also be more reliably partitioned and separated within the pack case 200.

[0064] Each of the partition members 300 may have an accommodation space capable of accommodating the respective cell assemblies 100 therein, and may be provided as a hollow structure having an opening exposed in the vertical direction (Z-axis direction). Regarding the accommodation space, an example of one partition member 300 and a cell assembly 100 accommodated in one partition member 300 will be considered as follows. The accommodation width W1 of the accommodation space of the partition member 300 may be set to be equal to or smaller than the overall width W2 of the cell assembly 100. This is to further improve the adhesion performance of the partition member 300 made of the flexible material to both side surfaces of the cell assembly 100. More preferably, in one embodiment of the present invention, the accommodation width W1 of the accommodation space of the partition member 300 may be formed to be smaller than the overall width W2 of the cell assembly 100 to further improve the adhesion performance.

[0065] The partition members 300 may be disposed at predetermined intervals from each other in an arrangement direction (X-axis direction) of the cell assemblies 100. Specifically, the partition members 300 may space the cell assemblies 100 at predetermined intervals within the pack case 200.

[0066] Through this spacing structure, when a thermal event such as thermal runaway occurs in any of the cell assemblies 100, the cell assembly 100 in which the abnormal situation occurs is separated from the adjacent cell assembly 100 by the space created by the spacing in addition to the partition member 300, thereby minimizing the risk of heat propagation or delaying it as much as possible.

[0067] The spacing structure of the partition members 300 can be considered in more detail as follows. The partition members 300 facing each other in the arrangement direction (X-axis direction) can be arranged to have a first interval d1, and the partition members 300 facing the inner wall of the pack case 200 in the arrangement direction (X-axis direction) can be arranged to have a second interval d2. The first interval d1 can be designed in consideration of the cell expansion width in all lateral directions (X-axis direction) of the two cell assemblies 100 facing each other. In addition, the second interval d2 can be designed in consideration of the cell expansion width in the lateral direction (X-axis direction) of one cell assembly 100, since it faces the inner wall of the pack case 200. Therefore, the first interval d1 can be formed larger than the second interval d2. Preferably, the first interval d1 can be set to be at least twice as large as the second interval d2.

[0068] The one or more battery cells 110 of the cell assemblies 100 will be discussed in more detail below.

[0069] As discussed above, the one or more battery cells 110 may be provided as pouch-type secondary batteries, and each may include an electrode assembly, a pair of electrode leads electrically connected to the electrode assembly, and a battery case that houses the electrode assembly with a portion of the pair of electrode leads exposed.

[0070] A vent unit 115 may be provided at a lower portion (-Z-axis direction) of the plurality of battery cells 110. The vent unit 115 may be broken or melted at a predetermined temperature or pressure or higher so that gas or flames inside the battery cell 110 can be discharged in an abnormal situation such as overheating, and may guide the discharge of gas, flames, etc. inside the battery cell 110 to the outside of the battery cell 110.

[0071] The partition member 300 may surround the side surfaces of the plurality of cell assemblies 100 while exposing the vent portion 115. Since the partition member 300 exposes the vent portion 115, it may guide smooth exhaust of ejected materials such as gas and flames through the vent portion 115 without interfering with the vent portion 115.

[0072] The pack case 200 according to an embodiment of the present invention will be discussed in more detail below.

[0073] The bottom plate 212 of the pack case 200 faces the vent portion 115 and breaks or melts when ejections such as gas or flame are discharged through the vent portion 115, thereby enabling the gas or flame to be discharged to the outside of the pack case 200.

[0074] In one embodiment of the present invention, the bottom plate 212 of the pack case 200 is disposed to face the vent portion 115, thereby simplifying the discharge path of the ejected material through the vent portion 115, and in an abnormal situation such as a thermal event, the ejected material can be more quickly discharged to the outside of the pack case 200. That is, in one embodiment of the present invention, the bottom plate 212 of the pack case 200 is disposed to face the vent portion 115, thereby guiding venting in a downward direction (-Z axis direction) of the battery pack 10.

[0075] Therefore, the battery pack 10 according to one embodiment of the present invention can more quickly exhaust ejections such as high-temperature gases and flames generated when a thermal event occurs to the outside of the pack case 200 by inducing bottom venting in the shortest path as a directional vent.

[0076] The pack case 200 may include a case body 210 and a case cover 230 .

[0077] The case body 210 can support the plurality of cell assemblies 100 and the partition member 300. Furthermore, the case body 210 can be provided with the above-mentioned accommodation space capable of accommodating the plurality of cell assemblies 100 and the partition member 300.

[0078] The case cover 230 is coupled to the case body 210 and can accommodate the plurality of cell assemblies 100 and the partition member 300. Specifically, the case cover 230 can be coupled to a side plate 518 of the case body 210, which will be described later, by bolting or bonding, and can be coupled to the case body 210. The coupling structures such as the bolting and bonding are merely exemplary, and it goes without saying that other coupling structures for stably coupling the case cover 230 and the case body 210 to each other are also possible.

[0079] The bottom plate 212 of the case body 210 faces the vent portion 115 and may be broken or melted to discharge ejections such as gas or flame to the outside of the pack case 200 when ejecting ejections such as gas or flame through the vent portion 115. The bottom plate 212 of the case body 210 may have a relatively thin thickness compared to the case body 210 for easier breaking or melting.

[0080] Hereinafter, the case body 210 will be considered in more detail.

[0081] The case body 210 may include a bottom plate 212 and a side plate 218 .

[0082] The bottom plate 212 supports the plurality of cell assemblies 100 and the plurality of partition members 300 , and may be disposed opposite the vent portions 115 of the battery cells 110 of the plurality of cell assemblies 100 .

[0083] The bottom plate 212 can break or melt at or above a predetermined temperature or pressure to release ejections such as high-temperature gas or flames from inside the pack case 200 during the thermal event, thereby opening the inside of the pack case 200. The bottom plate 212 can be formed to have a thickness thinner than that of the side plate 218 for easier breaking or melting.

[0084] On the other hand, the bottom plate 212 may include a vent unit as a separate member that melts or breaks at the above-mentioned predetermined temperature or pressure.

[0085] Therefore, the bottom plate 212 itself functions as a vent unit, or a separate vent unit is provided on the bottom plate 212, thereby realizing directional venting for lower venting to the bottom side of the pack case 200 during the thermal event.

[0086] The side plates 218 may be integrally formed with the bottom plate 212 and extend vertically from both sides of the bottom plate 212. Meanwhile, the side plates 218 may be provided as separate members from the bottom plate 212 and may be connected to the bottom plate 212 by bolting or bonding to form the case body 210. The side plates 218 may be connected to the case cover 230 to form the exterior of the side of the pack case 200.

[0087] Hereinafter, a vent mechanism for discharging high-temperature gas or flames inside the pack case 200 in an abnormal situation such as a thermal event of the battery pack 10 according to an embodiment of the present invention will be considered in more detail.

[0088] FIG. 4 is a diagram for explaining a vent mechanism of the battery pack 10 of FIG. 1 during a thermal event.

[0089] 4, an abnormal situation such as a thermal event may occur in at least one of the cell assemblies 100 of the battery pack 10. The thermal event may refer to a thermal runaway situation caused by overheating of at least one battery cell 110 of the cell assembly 100.

[0090] When a thermal runaway situation occurs in a particular cell assembly 100 in the pack case 200, if heat is transmitted to an adjacent cell assembly 100, it can pose a significant risk of a chain fire or even an explosion of the entire battery pack 10, so it is important to prevent or delay such heat transmission as much as possible.

[0091] In one embodiment of the present invention, as discussed above, the partition member 300 partitions and covers adjacent cell assemblies 100 in the side direction (X-axis direction) of the battery pack 10, thereby effectively preventing or delaying heat propagation to the adjacent cell assembly 100 during a thermal event situation of a particular cell assembly 100.

[0092] Meanwhile, during the thermal event, ejections G such as high-temperature gas or flames escaping through the vent 115 of at least one battery cell 110 of the cell assembly 100 in which a thermal event has occurred may be ejected toward the lower portion (-Z axis direction) of the battery pack 10 through the bottom plate 212 of the case body 210 of the pack case 200. The bottom plate 212 may break or melt at or above a predetermined temperature or pressure inside the pack case 200 during the thermal event so that the ejections G such as high-temperature gas or flames can be exhausted to the outside of the pack case 200.

[0093] In one embodiment of the present invention, the partition member 300 is provided in a structure that surrounds only both sides of the cell assembly 100 so as not to interfere with the vent portion 115 of the battery cell 110 of the cell assembly 100, thereby guiding more rapid induced ejection of the ejection material G.

[0094] In addition, in one embodiment of the present invention, the vent portion 115 of the battery cell 110 of the cell assembly 100 is positioned directly opposite the bottom plate 212 of the pack case 200, so that the ejection path of the ejection material G for the lower vent can be realized in the shortest distance.

[0095] FIG. 5 is a diagram illustrating a battery pack 20 according to another embodiment of the present invention, and FIG. 6 is a diagram illustrating a vent mechanism of the battery pack 20 of FIG. 5 during a thermal event.

[0096] Since the battery pack 20 according to this embodiment is similar to the battery pack 10 according to the above embodiment, a duplicated description of the configurations that are the same or similar to those of the above embodiment will be omitted, and the following discussion will focus on the differences from the above embodiment.

[0097] 5 and 6, the battery pack 20 may include a plurality of cell assemblies 100, a pack case 200, a plurality of compartment members 300, and a potting resin 400.

[0098] The plurality of cell assemblies 100, the pack case 200, and the plurality of partition members 300 are substantially the same as or similar to those in the above-described embodiment, and therefore, overlapping descriptions will be omitted below.

[0099] The potting resin 400 may include a silicone resin. Also, the potting resin 400 may include glass bubbles. The glass bubbles may reduce the specific gravity of the potting resin 400, thereby increasing the energy density per weight.

[0100] The potting resin 400 may be filled in a space between the plurality of cell assemblies 100 and the case cover 230 of the pack case 200. That is, the potting resin 400 may be filled in an upper (+Z-axis direction) space of the plurality of cell assemblies 100 inside the pack case 200. In this manner, the potting resin 400 is filled so as to cover the upper (+Z-axis direction) space of the cell assemblies 100 inside the pack case 200, and therefore, during the above-mentioned thermal event, it is possible to effectively prevent the ejection G, such as the high-temperature gas or flame, from moving in the upward direction (+Z-axis direction) inside the pack case 200 or from flowing into the upper space inside the pack case 200.

[0101] The potting resin 400 may also be filled in spaces between the cell assemblies 100. That is, the potting resin 400 may also be filled between the partition members 300 surrounding the cell assemblies 100. Thus, when a thermal event or damage occurs due to an abnormality in at least one specific battery cell 110 of the cell assemblies 100, the potting resin 400, together with the partition member 300, prevents heat propagation to the adjacent cell assembly 100, thereby effectively preventing further thermal runaway due to heat propagation to the adjacent cell assembly 100. In addition, the potting resin 400 may also act as an insulator that prevents current flow to the adjacent cell assembly 100 when a thermal event or damage occurs in the at least one specific battery cell 110.

[0102] The potting resin 400 may be continuously filled in the space above the cell assemblies 100 (+Z-axis direction), between the partition members 300 in the arrangement direction (X-axis direction) of the cell assemblies 100, and in the inner wall spaces on both sides (X-axis direction) of the pack case 200 without any interruption or separation space within the pack case 200. As described above, the potting resin 400 according to the embodiment of the present invention is continuously filled in the pack case 200 without any interruption, so that uniform heat dispersion is achieved without any heat dispersion deviation of the cell assemblies 100, and the cooling performance of the battery pack 20 can be improved.

[0103] The potting resin 400 may include a material having high specific heat performance. Accordingly, the potting resin 400 increases thermal mass, thereby delaying a temperature rise of the battery cell 110 even in a situation where the battery cell 110 of the cell assembly 100 is rapidly charged and discharged, thereby preventing a rapid temperature rise of the battery cell 110.

[0104] The potting resin 400 may include a material having high heat resistance, so that the potting resin 400 can effectively prevent a chain reaction of fire or further thermal runaway caused by heat propagation to an adjacent cell assembly 100 when a thermal event such as overheating occurs in a battery cell 110 of at least one specific cell assembly 100 of the plurality of cell assemblies 100.

[0105] The potting resin 400 may include a material having high flame retardancy, thereby minimizing the risk of fire when a thermal event such as overheating occurs in the battery cell 110 of at least one specific cell assembly 100 of the plurality of cell assemblies 100.

[0106] As described above, in the battery pack 20 according to one embodiment of the present invention, the potting resin 400 prevents the ejection material G that escapes from the vent portion 115 of the battery cell 110 during a thermal event from flowing upward (in the +Z-axis direction) inside the pack case 200, and more reliably guides the induced ejection for the lower vent.

[0107] FIG. 7 is a diagram illustrating a battery pack 30 according to still another embodiment of the present invention.

[0108] Since the battery pack 30 according to this embodiment is similar to the battery pack 10 according to the above embodiment, a duplicated description of the configurations that are the same or similar to those of the above embodiment will be omitted, and the following discussion will focus on the differences from the above embodiment.

[0109] Referring to FIG. 7 , the battery pack 30 may include a plurality of cell assemblies 100 , a plurality of compartment members 300 , and a pack case 500 .

[0110] The plurality of cell assemblies 100 and the plurality of partition members 300 are substantially the same as or similar to those in the above embodiment, and therefore, a duplicated description will be omitted below.

[0111] The pack case 500 may include a case body 510 and a case cover 530. In this embodiment, the case cover 530 is similar to the above embodiment, so the case body 510 will be mainly discussed below.

[0112] The case body 510 may include a bottom plate 512 and a side plate 518. In this embodiment, the side plate 518 is similar to the above embodiment, so the following description will focus on the bottom plate 512.

[0113] The bottom plate 512 may have a receiving portion 514 formed therein.

[0114] The receiving portion 514 may receive the cell assembly 100 and a portion of the partition member 300. Specifically, the receiving portion 514 may receive each of the cell assemblies 100 surrounded by the partition member 300. More specifically, the lower end of each cell assembly 100 surrounded by the partition member 300 and the lower end of the partition member 300 may be inserted into the receiving portion 514. Thus, the receiving portion 514 may be formed to have an uneven shape on the upper side (+Z-axis direction) of the inner surface at the bottom of the bottom plate 512 along the arrangement direction of the cell assemblies 100 (X-axis direction).

[0115] The receiving portion 514 may include a seating portion 516 and a step portion 517. The seating portion 516 may receive the lower end of the cell assembly 100 and the partition member 300. The step portion 517 may be provided at a predetermined height between the cell assembly 100 surrounded by the partition member 300. Meanwhile, the thickness of the seating portion 516 may be thinner than the step portion 517 and the side plate 518. This is because the seating portion 516 faces the vent portion 115 of the battery cell 110 of the cell assembly 100, and thus the bottom plate 512 is more easily broken or melted during the thermal event, thereby opening the bottom plate 512 more quickly.

[0116] The mounting parts 516 and the stepped parts 517 may be alternately arranged along the longitudinal direction (X-axis direction) of the bottom plate 512. In other words, in the longitudinal direction (X-axis direction) of the bottom plate 512, one stepped part 517 may be arranged between two mounting parts 516, and one mounting part 516 may be arranged between two stepped parts 517. However, in the bottom plate 512, stepped parts 517 may be arranged at both ends adjacent to the side plates 518 of the case body 510 of the pack case 500.

[0117] In the battery pack 30 according to this embodiment, the accommodating portion 514 provided on the bottom plate 512 of the pack case 500 enables the multiple cell assemblies 100 and the partition member 300 to be more stably accommodated and supported within the pack case 200.

[0118] FIG. 8 is a diagram illustrating a battery pack 40 according to still another embodiment of the present invention.

[0119] Since the battery pack 40 according to this embodiment is similar to the battery pack 10 according to the above embodiment, a duplicated description of the configurations that are the same or similar to those of the above embodiment will be omitted, and the following discussion will focus on the differences from the above embodiment.

[0120] Referring to FIG. 8 , the battery pack 40 may include a plurality of cell assemblies 100 , a plurality of compartment members 300 , and a pack case 600 .

[0121] The plurality of cell assemblies 100 and the plurality of partition members 300 are substantially the same as or similar to those in the above embodiment, and therefore, a duplicated description will be omitted below.

[0122] The pack case 600 may include a case body 610 and a case cover 630. In this embodiment, the case cover 630 is similar to the above embodiment, so the following description will focus on the case body 610.

[0123] The case body 610 may include a bottom plate 612 and a side plate 618. In this embodiment, the side plate 618 is similar to the above embodiment, so the following description will focus on the bottom plate 612.

[0124] The bottom plate 612 may have a vent guide 615 formed therein.

[0125] The vent guide 615 may break or melt during the above-mentioned thermal event, and may guide ejections such as high-temperature gas and flames emitted from the vent portion 115 of the battery cell 110 to the underside (-Z axis direction) of the bottom plate 612.

[0126] The vent guide 615 may be formed to have a predetermined depth from the outer surface of the bottom of the bottom plate 612, and may have a relatively thin thickness at the bottom of the bottom plate 612. Also, the vent guide 615 may be formed at a position corresponding to the bottom of the vent portion 115 of the battery cell 110 of the plurality of cell assemblies 100. Thus, unlike the bottom plate 512 of FIG. 7, the bottom plate 612 may be formed to have a structure having an uneven shape on the lower side (-Z axis direction) of the outer surface at the bottom, rather than on the upper side (+Z axis direction) of the inner surface at the bottom, due to the vent guide 615 provided at a predetermined depth on the lower side (-Z axis direction) of the outer surface at the bottom of the bottom plate 612.

[0127] In this embodiment, the vent guide 615 abuts the vent portion 115 of the battery cell 110 and has a relatively thin thickness at the bottom of the bottom plate 612, thereby achieving more rapid bottom induction venting during the above-mentioned thermal event.

[0128] In addition, in an embodiment of the present invention, the portion of the bottom plate 612 between the vent guides 615 is formed in a structure that protrudes further downward (in the -Z axis direction) on the lower side (-Z axis direction) of the outer surface at the bottom of the bottom plate 612, so that it is possible to effectively prevent the ejection that has escaped from a specific vent guide 615 or particles generated by the breakage or melting of a specific vent guide 615 from dispersing to the adjacent vent guide 615. That is, in an embodiment of the present invention, the uneven structure on the lower side (-Z axis direction) of the outer surface of the bottom plate 612 provided by the vent guide 615 can effectively prevent the ejection from dispersing to the left and right directions (X axis direction) of the bottom plate 612 when the ejection is induced to eject downward.

[0129] Therefore, in one embodiment of the present invention, the vent guide 615 can more reliably guide the discharge direction of the ejection material toward the lower side of the pack case 600 (in the -Z axis direction) during the thermal event.

[0130] FIG. 9 is a diagram illustrating a battery pack 50 according to still another embodiment of the present invention, and FIG. 10 is a diagram illustrating a vent mechanism of the battery pack 50 of FIG. 9 during a thermal event.

[0131] Since the battery pack 50 according to this embodiment is similar to the battery pack 10 according to the above embodiment, a duplicated description of the configurations that are the same or similar to those of the above embodiment will be omitted, and the following discussion will focus on the differences from the above embodiment.

[0132] 9 and 10, the battery pack 50 may include a plurality of cell assemblies 100, a plurality of compartment members 300, and a pack case 700.

[0133] The plurality of cell assemblies 100 and the plurality of partition members 300 are substantially the same as or similar to those in the above embodiment, and therefore, a duplicated description will be omitted below.

[0134] The pack case 700 may include a case body 710 , a case cover 730 , a guide channel 750 , and a vent unit 770 .

[0135] The case body 710 may include a bottom plate 712 and a side plate 718. In this embodiment, the side plate 718 is similar to the above embodiment, so the following description will focus on the bottom plate 712.

[0136] The bottom plate 712 may include a first plate 713 and a second plate 715 .

[0137] The first plate 713 may support the plurality of cell assemblies 100 and the partition member 300. The first plate 713 may be disposed to directly face the vent portions 115 of the plurality of battery cells 110 and may have a relatively thin thickness for easier fracture or melting during a thermal event as described above. For example, the first plate 713 may be provided with a thickness thinner than that of a second plate 715 described below.

[0138] The second plate 715 may be disposed at a predetermined distance from the first plate 713 in a height direction (Z-axis direction) of the pack case 600. Thus, a predetermined space may be formed between the second plate 715 and the first plate 713. This predetermined space may function as a guide channel 750, which will be described later.

[0139] The case cover 730 is substantially the same as or similar to the above embodiment, and therefore, a duplicated description will be omitted below.

[0140] The guide channel 750 may be formed in a space between the first plate 713 and the second plate 715. The guide channel 750 may guide ejections G, such as high-temperature gas and flames, which escape through the vent portion 115 of the battery cell 110 and the first plate 713 during a thermal event of the cell assembly 100, to a vent unit 770, which will be described later. The guide channel 750 may also guide ejections G, such as particles, which are generated due to breakage or melting of the first plate 713 during the thermal event, to the vent unit 770, which will be described later.

[0141] The vent unit 770 is provided on the second plate 715, and can break or melt during the thermal event to discharge the ejection material G guided to the guide passage 750 side to the outside of the pack case 700. The vent unit 770 can be provided with a structure that opens at a predetermined temperature or pressure or communicates the inside and outside of the pack case 700, in addition to the above-mentioned structure that breaks or melts at a predetermined temperature or pressure. As a result, the vent structure of the vent unit 770 can be both a passive structure or an active structure that can discharge the ejection material G. Meanwhile, the mounting position of the vent unit 770 on the second plate 715 can be provided at a position corresponding to the mounting position of a fire extinguishing device or a component for fire suppression outside the pack case 700. It goes without saying that the vent unit 770 can be provided in a plurality of units on the second plate 715.

[0142] In the battery pack 50 according to one embodiment of the present invention, the bottom plate 712 composed of the first and second plates 713, 715 forming the guide passage 750 can effectively discharge ejected materials such as particles that may be generated on the side of the first plate 713 facing the battery cell 110 during the thermal event to the outside of the pack case 700.

[0143] In addition, in the battery pack 50 according to an embodiment of the present invention, the vent unit 770 provided on the second plate 715 can maximize the induced ejection effect in a specific direction when venting with a directional downward direction.

[0144] FIG. 11 is a diagram for explaining an automobile 1 according to an embodiment of the present invention.

[0145] 11, an automobile 1 according to an embodiment of the present invention may include one or more of the battery packs 10, 20, 30, 40, and 50 according to the present invention. Furthermore, the automobile 1 according to an embodiment of the present invention may further include various other components included in an automobile, in addition to the battery packs 10, 20, 30, 40, and 50 according to an embodiment of the present invention. For example, the automobile 1 according to an embodiment of the present invention may further include a vehicle body, a motor, a control device such as an ECU (electronic control unit), and the like, in addition to the battery packs 10, 20, 30, 40, and 50 according to an embodiment of the present invention.

[0146] Furthermore, it goes without saying that the battery packs 10, 20, 30, 40, 50 according to the above-described embodiments of the present invention can be provided in other devices, mechanisms, and equipment, such as an energy storage system using a secondary battery, in addition to the automobile 1.

[0147] As described above, since the automobile 1 according to one embodiment of the present invention includes the battery packs 10, 20, 30, 40, 50 of the above embodiments, the automobile 1 can also ensure safety against the above-mentioned thermal events.

[0148] According to the various embodiments described above, it is possible to provide the battery packs 10, 20, 30, 40, 50 and the automobile 1 including the battery packs, which can improve safety against thermal events.

[0149] Furthermore, the various embodiments as described above can provide the battery packs 10, 20, 30, 40, 50 that can be slimmed down and have improved energy efficiency, and the automobile 1 that includes the battery packs.

[0150] Although the preferred embodiments of the present invention have been shown and described above, the present invention is not limited to the above-mentioned specific embodiments, and various modifications can be made by a person having ordinary knowledge in the technical field to which the invention pertains without departing from the gist of the present invention as claimed in the claims, and such modifications should not be understood separately from the technical ideas and perspectives of the present invention. [Explanation of symbols]

[0151] 1. Automobiles 10 Battery Pack 20 Battery Pack 30 Battery Pack 40 Battery Pack 50 Battery Pack 100 Cell Assembly 110 Battery Cell 115 Vent 200 pack case 210 Case body 212 Bottom Plate 218 Side Plate 230 Case Cover 300 Partition members 400 Potting Resin 500 pack case 510 Case body 512 Bottom Plate 514 Storage unit 516 Arrival Section 517 Step 518 Side Plate 530 Case Cover 600 pack case 610 Case body 612 Bottom Plate 615 Vent Guide 618 Side Plate 630 Case Cover 700 pack case 710 Case body 712 Bottom Plate 713 First Plate 715 2nd Plate 718 Side Plate 730 Case Cover 750 Guide passage 770 Vent Unit d1 First interval d2 2nd interval G ejecta W1 Storage width W2 Overall width

Claims

1. a plurality of cell assemblies including one or more battery cells and arranged in at least one row; a pack case that houses a plurality of the cell assemblies; a partition member that partitions the plurality of cell assemblies within the pack case, the partition member being made of a flexible material and tightly surrounding the plurality of cell assemblies.

2. The partition member is The battery pack according to claim 1 , wherein the cell assembly is in intimate contact with side surfaces of the cell assemblies in an arrangement direction of the cell assemblies.

3. The partition member is 2. The battery pack according to claim 1, wherein the battery pack is made of a fire-resistant rubber material.

4. The partition member is 2. The battery pack according to claim 1, wherein the battery pack is made of an insulating rubber material.

5. The partition member is The battery pack according to claim 1 , wherein the first and second cell assemblies are disposed between the first and second cell assemblies in an arrangement direction of the first and second cell assemblies.

6. The partition member is A plurality of the cell assemblies are provided corresponding to the number of the cell assemblies, The plurality of partition members include The battery pack according to claim 1 , wherein the battery pack is in close contact with both side surfaces of each of the cell assemblies.

7. The plurality of partition members include The battery pack according to claim 6 , wherein the cell assemblies are spaced apart from each other by a predetermined distance in an arrangement direction.

8. A vent portion is provided at a lower portion of the one or more battery cells, The partition member is The battery pack according to claim 1 , wherein the vent portion surrounds side portions of the plurality of cell assemblies while leaving the vent portion exposed.

9. The bottom of the pack case is The battery pack according to claim 8 , wherein the insulating layer faces the vent portion and breaks or melts when gas or flame is discharged through the vent portion, thereby discharging the gas or flame to the outside of the pack case.

10. The pack case includes: a case body supporting a plurality of the cell assemblies and the partition member; a case cover coupled to the case body and housing the cell assemblies and the partition member; The bottom of the case body is The battery pack according to claim 8 , wherein the vent portion faces the vent portion and is broken or melted so that the gas or flame can be discharged to the outside of the pack case when the gas or flame is discharged through the vent portion.

11. The battery pack according to claim 10, further comprising a potting resin filled in spaces between the cell assemblies and the case cover.

12. The potting resin is The battery pack according to claim 11, wherein the space between the plurality of cell assemblies is filled.

13. A motor vehicle comprising a battery pack according to any one of claims 1 to 12.

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