Battery pack, and automobiles 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 an automobile including the battery pack, and more particularly, to a battery pack with improved safety against thermal events and an automobile including the battery pack.

[0002] This application claims priority based on 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, and all the contents disclosed in the specifications and drawings of the applications are incorporated into this application.

Background Art

[0003] Secondary batteries that are easy to apply according to product groups and have electrical characteristics such as high energy density are widely applied not only to portable devices but also to electric vehicles (EVs, Electric Vehicles) or hybrid electric vehicles (HEVs, Hybrid Electric Vehicles) driven by an electric drive source. Such secondary batteries not only have the main advantage of being able to dramatically reduce the use of fossil fuels but also have the advantage of not generating any by-products due to energy use, and thus are attracting attention as a new energy source for environmental consideration and improving energy efficiency.

[0004] Currently widely used types of rechargeable batteries include lithium-ion batteries, lithium polymer batteries, nickel-cadmium batteries, nickel-metal hydride batteries, and nickel-zinc batteries. The operating voltage of a single rechargeable battery cell is approximately 2.5V to 4.5V. Therefore, when a higher output voltage is required, multiple battery cells may be connected in series to form a battery pack. Also, depending on the required charge and discharge capacity of the battery pack, multiple battery cells may be connected in parallel to form a battery pack. Thus, the number of battery cells included in the battery pack can be set in various ways depending on the required output voltage or charge and discharge capacity.

[0005] On the other hand, when configuring a battery pack by connecting multiple battery cells in series or parallel, it is common practice to first configure a battery module containing at least one battery cell, and then use this at least one battery module to add other components to form a battery pack or battery rack.

[0006] However, when multiple secondary batteries (battery cells) or multiple battery modules are densely packed into a small space, they can become vulnerable to thermal events. In particular, if an event such as thermal runaway occurs in any of the battery cells, high-temperature gases, flames, and heat may be generated. If such gases, flames, and heat are transferred to other battery cells contained within the same battery module, an explosive chain reaction situation such as thermal propagation may occur. Furthermore, such a chain reaction could not only cause accidents such as fires and explosions in the battery module in question, but could also cause fires and explosions in other battery modules.

[0007] Furthermore, in the case of medium to large battery packs, such as those found in electric vehicles, the risk of thermal chain reactions is even higher because they contain a large number of battery cells and battery modules to increase output and / or capacity. In addition, in the case of battery packs installed in electric vehicles, there may be drivers or other users in the vicinity. Therefore, if a thermal event occurring in a particular battery module cannot be properly controlled and a chain reaction occurs, it could cause not only significant property damage but also loss of life.

[0008] Therefore, in the event of a thermal runaway caused by a heat event occurring at the battery module level within the battery pack, it is important that such high-temperature gases, flames, and particles are expelled from the battery pack more quickly in order to prevent greater dangers such as secondary ignition or explosion due to an increase in internal pressure within the battery pack.

[0009] However, within a battery pack, mechanisms for housing battery modules and structures for partitioning other battery modules are made of aluminum to ensure rigidity, and much of this material melts at around 600 degrees Celsius. During a thermal event, particles generated by the melting of these structures can either collapse the mechanisms of the battery modules or the structures for partitioning other battery modules within the battery pack, or block the discharge openings of the battery pack's vent unit, increasing the internal pressure of the battery pack and becoming a significant factor in causing greater damage such as secondary ignition or explosion of the battery pack.

[0010] Furthermore, in the case of conventional battery packs, there is a problem in that the collapse of the aforementioned mechanisms and structures such as vent units is accelerated when ejected materials such as high-temperature gases, flames, and particles generated during a thermal event flow into the gap space created by assembly tolerances between the components that make up the battery module mechanisms and the structures that partition the battery modules.

[0011] Therefore, it is necessary to find a way to provide a battery pack that can solve the above problems and improve safety against thermal events, and an automobile that includes such a battery pack. [Overview of the project] [Problems that the invention aims to solve]

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

[0013] Another object of the present invention is to provide a battery pack that can achieve a slimmer profile and improve energy efficiency, and an automobile including said battery pack.

[0014] However, the technical problems that this invention aims to solve are not limited to those described above, and any other problems not mentioned will be clearly understood by those skilled in the art from the description of the invention below. [Means for solving the problem]

[0015] To solve the above objectives, the present invention provides a battery pack comprising: a plurality of cell assemblies, each containing one or more battery cells and arranged in at least one row; a pack case for housing the plurality of cell assemblies; and a partitioning member made of a flexible material that partitions the plurality of cell assemblies within the pack case and closely surrounds the plurality of cell assemblies.

[0016] Furthermore, preferably, the partitioning member can be in close contact with the side surfaces of the plurality of cell assemblies in the direction of arrangement of the plurality of cell assemblies.

[0017] Furthermore, preferably, the partition member may be made of a fire-resistant rubber material.

[0018] Furthermore, preferably, the partition member may be made of an insulating rubber material.

[0019] Preferably, the partition members may be positioned between the plurality of cell assemblies in the direction of arrangement of the plurality of cell assemblies.

[0020] Preferably, the partition members are provided in a number corresponding to the number of cell assemblies, and the multiple partition members can be in close contact with both sides of each cell assembly.

[0021] Furthermore, preferably, the plurality of partition members may be arranged at a predetermined distance from each other in the arrangement direction of the plurality of cell assemblies.

[0022] Preferably, a vent is provided at the bottom of one or more of the battery cells, and the partition member can surround the side surfaces of the plurality of cell assemblies with the vent exposed.

[0023] Preferably, the bottom of the pack case faces the vent and breaks or melts when gas or flames are discharged through the vent, allowing the gas or flames to be discharged to the outside of the pack case.

[0024] Preferably, the pack case includes a case body that supports the plurality of cell assemblies and the partition members, and a case cover that is coupled to the case body and houses the plurality of cell assemblies and the partition members, wherein the bottom of the case body faces the vent and can be broken or melted to allow gas or flame to be discharged to the outside of the pack case when gas or flame is discharged through the vent.

[0025] Preferably, the battery pack may also include a potting resin that fills the space between the plurality of cell assemblies and the case cover.

[0026] Also, preferably, the potting resin can fill the space between the plurality of cell assemblies.

[0027] The present invention also provides a motor vehicle, characterized by including the battery pack according to the above-described embodiment.

Advantages of the Invention

[0028] According to various embodiments as described above, it is possible to provide a battery pack that can improve safety against thermal events, and a motor vehicle including the battery pack.

[0029] Also, according to various embodiments as described above, it is possible to provide a battery pack that can achieve slimming and improve energy efficiency, and a motor vehicle including the battery pack.

[0030] In addition to this, the present invention can have various effects, which will be described in each embodiment, or descriptions of effects that can be easily analogized 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 serve to further understand the technical idea of the present invention together with the detailed description of the invention. Therefore, the present invention should not be construed as being limited only to the matters described in the drawings.

Brief Description of the Drawings

[0032] [Figure 1] It is a diagram for explaining a battery pack according to an embodiment of the present invention. [Figure 2] It is a diagram for explaining a partitioning member surrounding the cell assembly of the battery pack in FIG. 1. [Figure 3] It is a diagram for explaining a partitioning member surrounding the cell assembly of the battery pack in FIG. 1. [Figure 4]This diagram illustrates the venting mechanism of the battery pack during a thermal event, as shown in Figure 1. [Figure 5] This figure illustrates a battery pack according to another embodiment of the present invention. [Figure 6] Figure 5 is a diagram illustrating the venting mechanism of the battery pack during a thermal event. [Figure 7] This figure illustrates a battery pack according to yet another embodiment of the present invention. [Figure 8] This figure illustrates a battery pack according to yet another embodiment of the present invention. [Figure 9] This figure illustrates a battery pack according to yet another embodiment of the present invention. [Figure 10] Figure 9 is a diagram illustrating the venting mechanism of the battery pack during a thermal event. [Figure 11] This is a diagram illustrating an automobile based on one embodiment of the present invention. [Modes for carrying out the invention]

[0033] Preferred embodiments of the present invention will be described in detail below with reference to the attached drawings. Prior to this, terms and words used in this specification and in the claims shall not be interpreted in their usual and dictionary sense, but rather in a sense and concept appropriate to the technical idea of ​​the present invention, in accordance with the principle that the inventor himself may appropriately define the concept of terms in order to best describe the invention.

[0034] Therefore, it should be understood that the configurations shown in the embodiments described herein represent only one of the most preferred embodiments of the present invention and do not represent the entire technical concept of the present invention, and that there may be a variety of equivalents and modifications that can be substituted therein at the time of filing this application.

[0035] On the other hand, while this specification may use terms indicating directions such as up, down, left, right, front, and back, such terms are for convenience of explanation and it will be obvious to those skilled in the art that they may change depending on the position of the object in question, the position of the observer, etc.

[0036] Figure 1 is a diagram illustrating a battery pack 10 according to one embodiment of the present invention, and Figures 2 and 3 are diagrams illustrating partition members 300 surrounding the cell assembly 100 of the battery pack 10 in Figure 1.

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

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

[0039] The plurality of battery cells 110 are secondary batteries and may be provided as pouch-type secondary batteries. Such plurality of battery cells 110 may be stacked on top of each other so that they can be electrically connected to one another. On the other hand, although this embodiment is described in which the plurality of battery cells 110 are provided as pouch-type secondary batteries, it goes without saying that the cell assembly may also be provided as an inter-stack of cylindrical secondary batteries or prismatic secondary batteries other than the pouch-type secondary batteries.

[0040] The cell assembly 100 may be provided in multiple quantities and arranged in at least one row. The arrangement of the multiple cell assemblies 100 varies depending on the required capacity, size, and shape of the battery pack 10, and arrangements in two or more rows or a matrix shape are also possible. Hereinafter, in one embodiment of the present invention, the description will be limited to a case in which the multiple 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 can accommodate the plurality of cell assemblies 100. To this end, the pack case 200 can be provided with a storage space capable of accommodating the plurality of cell assemblies 100. The specific structure of the pack case 200 will be discussed in more detail in the related explanation below.

[0042] The partitioning member 300 can partition the plurality of cell assemblies 100 within the pack case 200. Such a partitioning member 300 can support the plurality of cell assemblies 100 while guiding their placement within the pack case 200.

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

[0044] Conventionally, in the case of structures such as module housings for housing cell assemblies 100, unlike the partition members 300, they were generally made of aluminum as a metal material and were provided as frame assemblies with considerable weight. Therefore, conventional battery packs generally consisted of multiple battery modules, each composed of such cell assemblies and module housings for housing these cell assemblies. However, in the case of conventional battery packs, where the battery pack is composed of battery modules containing multiple cell assemblies inside, during a thermal event, the melting of metal structures such as module housings (melting at approximately 600 degrees Celsius) generates not only high-temperature gases and flames, but also a large amount of particles due to the melting of the structure. Such excessive ejecta, such as a large amount of particles, can cause problems such as the collapse of mechanisms that make up the battery modules and structures that partition the battery modules within the battery pack.

[0045] Furthermore, the excessive ejection of large amounts of particles as described above can block the vents of the vent unit, which are designed to release gases and flames to the outside of the battery pack. This increases the pressure inside the battery pack, creating a greater risk of secondary ignition 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. When high-temperature gases, flames, particles, and other ejected materials flow into such gap spaces during the aforementioned thermal events, it becomes more difficult to expel these ejected materials from within the battery pack, leading to a problem where the collapse of the battery pack's mechanisms and other components is accelerated.

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

[0048] Therefore, in one embodiment of the present invention, the flexible material partition member 300 reduces the amount of ejected material such as particles that melt due to high-temperature gases or flames during a thermal event, unlike conventional module housings made of metal. This significantly reduces the risk of structural collapse or vent path obstruction inside the battery pack 10 due to ejected material such as particles generated by the melting of metal. Thus, in one embodiment of the present invention, the partition member 300 minimizes the risk of secondary damage that may occur when a thermal event occurs.

[0049] Furthermore, in one embodiment of the present invention, the partition member 300, which is in close contact with the plurality of cell assemblies 100, prevents a gap space from forming between the plurality of cell assemblies 100 and the partition member 300, thereby fundamentally preventing problems such as the accumulation and retention of ejected materials such as high-temperature gases, 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 eliminates the need for a separate module housing or frame assembly made of a metal material that has considerable weight, as in conventional designs. This allows for a slimmer overall battery pack 10, reducing weight and significantly improving energy efficiency. In other words, the present invention enables the construction of a so-called CTP (Cell To Pack) type battery pack 10, in which the module housing is omitted by using the partition member 300.

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

[0052] In the following, we will examine the partition member 300 according to this embodiment of the present invention in more detail.

[0053] The partition member 300 can be in close contact with the side surfaces of the plurality of cell assemblies 100 in the direction of arrangement of the plurality of cell assemblies 100 (X-axis direction). In the case of pouch-type secondary batteries, generally, if overheating or charging and discharging continues, cell swelling called cell swelling occurs, and such cell swelling has the greatest deformation on the side surfaces of the battery cells 110.

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

[0055] The partition member 300 can surround the plurality of cell assemblies 100 while maintaining close contact only with their side surfaces. That is, the partition member 300 can have a housing space inside that can accommodate the cell assemblies 100, and can have an opening that exposes the upper and lower sides of the cell assemblies 100 in the vertical direction (Z-axis direction). For this purpose, the partition member 300 can be provided as a hollow structure having an opening exposed in the vertical direction (Z-axis direction). The cell assemblies 100 can be inserted into the housing space inside the partition member 300 through the vertical (Z-axis direction) opening of the partition member 300.

[0056] Therefore, in this embodiment, the convenience of the worker during the assembly process of the cell assembly 100 and the partition member 300 can be improved. Furthermore, in this embodiment, since the partition member 300 does not cover the upper and lower sides of the multiple cell assemblies 100 in the vertical direction (Z-axis direction), 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] On the exposed opening side below the partition member 300, the bottoms of the multiple battery cells 110 of the multiple cell assemblies 100 can either contact the bottom plate 212 of the case body 210 of the pack case 200 (described later) or be positioned at a predetermined distance apart. On the other hand, the bottoms of the battery cells 110 of the multiple cell assemblies 100 are provided with vents 115 for discharging internal gases during thermal events, which will be discussed in more detail in the related explanation below. In this way, the partition member 300 according to this embodiment can solve the interference problem with the vents 115 of the multiple battery cells 110 through the 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 when heated to approximately 1300 degrees Celsius in order to ensure fire resistance.

[0059] In one embodiment of the present invention, the partition member 300 made of the fire-resistant rubber material can withstand high-temperature gases and flames without changing shape for a considerable amount of time during a thermal event, thereby delaying the heat propagation rate from the cell assembly 100 where the thermal event occurred to the adjacent cell assembly 100 as much as possible, and significantly reducing the risk of generating a large amount of ejected material such as particles due to melting.

[0060] The partition member 300 may be made of an insulating rubber material. In one embodiment of the present invention, since the partition member 300 made of such an insulating material also ensures insulating performance, even if an electrical problem occurs in any of the cell assemblies 100, it is possible to effectively prevent short circuits and other problems that may occur in a chain reaction on the adjacent cell assemblies 100.

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

[0062] The partition members 300 may be provided in multiple quantities corresponding to the number of the multiple cell assemblies 100. The multiple partition members 300 can be in close contact with both sides of each cell assembly 100. Here, each of the multiple partition members 300 can accommodate one cell assembly 100. That is, each partition member 300 can accommodate each cell assembly 100 and can also closely surround both sides of each cell assembly 100.

[0063] In one embodiment of the present invention, the partition members 300 are provided in a plurality corresponding to the number of cell assemblies 100, and each cell assembly 100 is housed within it. This allows for more stable support of the plurality of cell assemblies 100, and also allows for more reliable partitioning and separation of the plurality of cell assemblies 100 within the pack case 200.

[0064] Each of the plurality of partition members 300 may be provided as a hollow structure having an opening exposed in the vertical direction (Z-axis direction), and having a housing space inside which each cell assembly 100 can be housed. Regarding the housing space, as an example, consider one partition member 300 and a cell assembly 100 housed within one partition member 300 as follows. The housing width W1 of the housing space of the partition member 300 may be the same as or smaller than the overall width W2 of the cell assembly 100. This is to further improve the adhesion performance of the flexible material partition member 300 to both sides of the cell assembly 100. More preferably, in one embodiment of the present invention, the housing width W1 of the housing space of the partition member 300 may be formed smaller than the overall width W2 of the cell assembly 100 in order to further improve the adhesion performance.

[0065] The plurality of partition members 300 can be arranged at a predetermined distance from each other in the direction of arrangement of the plurality of cell assemblies 100 (X-axis direction). Specifically, the plurality of partition members 300 can be arranged to space the plurality of cell assemblies 100 at a predetermined interval within the pack case 200.

[0066] Through this spaced-out arrangement, if a thermal event such as thermal runaway occurs in any of the cell assemblies 100, the cell assembly 100 experiencing the abnormal condition is separated not only from the adjacent cell assemblies 100 and the partition member 300, but also by the space created by the spaced-out arrangement. Therefore, the risk of heat propagation can be minimized or delayed as much as possible.

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

[0068] Below, we will examine in more detail one or more battery cells 110 of the aforementioned cell assembly 100.

[0069] As discussed above, one or more battery cells 110 are provided as pouch-type secondary batteries and may each be configured to 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] The lower part (-Z axis direction) of the plurality of battery cells 110 may be provided with a vent section 115. The vent section 115 is designed to rupture or melt at a predetermined temperature or pressure above a predetermined level, allowing gases, flames, and other ejected material from inside the battery cell 110 to be discharged in the event of an abnormal situation such as overheating, thereby guiding the discharge of gases, flames, and other ejected material from inside the battery cell 110 to the outside of the battery cell 110.

[0071] The partition member 300 can surround the side surfaces of the multiple cell assemblies 100 with the vent portion 115 exposed. Because the partition member 300 exposes the vent portion 115, it can guide the smooth discharge of ejected materials such as gas and flames through the vent portion 115 without interfering with the vent portion 115.

[0072] The following section will examine the pack case 200 according to one embodiment of the present invention in more detail.

[0073] The bottom plate 212 of the pack case 200 faces the vent portion 115 and breaks or melts when ejected material such as gas or flames is discharged through the vent portion 115, allowing the gas or flames 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 positioned to face the vent portion 115, thereby simplifying the discharge path of ejected material through the vent portion 115 and allowing the ejected material to be discharged more quickly to the outside of the pack case 200 in the event of an abnormal situation such as a thermal event. That is, in one embodiment of the present invention, the bottom plate 212 of the pack case 200 is positioned to face the vent portion 115, thereby guiding the vent of the battery pack 10 downwards (in the -Z axis direction).

[0075] Therefore, the battery pack 10 according to one embodiment of the present invention can more quickly discharge ejecta such as high-temperature gases and flames generated when the thermal event occurs to the outside of the pack case 200 by inducing venting at the bottom along 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 members 300. The case body 210 can also be provided with the above-mentioned storage space capable of accommodating the plurality of cell assemblies 100 and the partition members 300.

[0078] The case cover 230 is connected to the case body 210 and can accommodate the plurality of cell assemblies 100 and the partition members 300. Specifically, the case cover 230 can be connected to the case body 210 by bolting or bonding the side plates 518 of the case body 210, as described later. The bolting and bonding structures are merely illustrative examples, and it goes without saying that other types of connection structures are also possible for stably connecting the case cover 230 and the case body 210 to each other.

[0079] The bottom plate 212 of the case body 210 faces the vent portion 115 and can be broken or melted to allow ejected materials such as gas and flames to be discharged to the outside of the pack case 200 when ejected materials such as gas and flames passing through the vent portion 115. The bottom plate 212 of the case body 210 can have a relatively thin thickness to facilitate easier breaking or melting.

[0080] The following provides a more detailed examination of the aforementioned case body 210.

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

[0082] The bottom plate 212 supports the plurality of cell assemblies 100 and the plurality of partition members 300, and can be positioned opposite the vent portion 115 of the battery cell 110 of the plurality of cell assemblies 100.

[0083] The bottom plate 212 can rupture or melt at a predetermined temperature or pressure above a predetermined level, allowing the inside of the pack case 200 to be opened up so that hot gases, flames, and other ejected material inside the pack case 200 can be discharged during the thermal event. Such a bottom plate 212 may be formed to have a thinner thickness than the side plate 218 for easier rupture or melting.

[0084] On the other hand, the bottom plate 212 may also be equipped with a vent unit as a separate component that melts or breaks at the predetermined temperature or pressure described above.

[0085] Therefore, by having the bottom plate 212 itself function as a vent unit, or by providing a separate vent unit on the bottom plate 212, directional venting for downward venting to the bottom side of the pack case 200 during the heat event can be realized.

[0086] The side plate 218 is formed integrally with the bottom plate 212 and can extend vertically from both sides of the bottom plate 212. Alternatively, the side plate 218 can be provided as a separate component from the bottom plate 212 and connected to the bottom plate 212 by bolting, bonding, or other means to constitute the case body 210. Such a side plate 218 can be connected to the case cover 230 to form the side appearance of the pack case 200.

[0087] In the following section, we will examine in more detail the vent mechanism for discharging high-temperature gases, flames, etc., from inside the pack case 200 in the event of an abnormal situation such as a thermal event in the battery pack 10 according to this embodiment of the present invention.

[0088] Figure 4 is a diagram illustrating the venting mechanism of the battery pack 10 in Figure 1 during a thermal event.

[0089] Referring to Figure 4, an abnormal situation such as a thermal event may occur in at least one of the multiple cell assemblies 100 of the battery pack 10. This 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 condition occurs in a specific cell assembly 100 within the pack case 200, heat propagation to adjacent cell assemblies 100 can lead to a chain reaction of fires or even the explosion of the entire battery pack 10, posing a significant risk. Therefore, it is important to prevent or delay such heat propagation as much as possible.

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

[0092] On the other hand, during the thermal event, ejected material G such as high-temperature gas or flames that escapes through the vent portion 115 of at least one battery cell 110 of the cell assembly 100 where the thermal event occurred may be ejected to the lower part (-Z axis direction) of the battery pack 10 via the bottom plate 212 of the case body 210 of the pack case 200. The bottom plate 212 can rupture or melt at a predetermined temperature or pressure above a predetermined level inside the pack case 200 during the thermal event, so as to allow the ejected material G such as high-temperature gas or flames to be discharged to the outside of the pack case 200.

[0093] In one embodiment of the present invention, the partition member 300 is provided in such a structure that it 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 the ejected material G to be ejected more quickly.

[0094] Furthermore, in one embodiment of the present invention, the vent portion 115 of the battery cell 110 of the cell assembly 100 is positioned to directly face the bottom plate 212 of the pack case 200, thereby enabling the shortest possible ejection path for the ejected material G for the lower vent.

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

[0096] Since the battery pack 20 according to this embodiment is similar to the battery pack 10 in the above embodiment, redundant explanations of the same or similar components as in the above embodiment will be omitted, and the following discussion will focus on the differences from the above embodiment.

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

[0098] Since 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 embodiment, redundant explanations will be omitted below.

[0099] The potting resin 400 may contain silicone resin. Furthermore, the potting resin 400 may contain glass bubbles. These glass bubbles can reduce the specific gravity of the potting resin 400 and increase its energy density relative to its weight.

[0100] The potting resin 400 can be filled into the space between the plurality of cell assemblies 100 and the case cover 230 of the pack case 200. That is, the potting resin 400 can be filled into the space above the plurality of cell assemblies 100 in the upper (+Z axis direction) of the pack case 200. In this way, since the potting resin 400 is filled inside the pack case 200 to cover the space above the cell assemblies 100 in the upper (+Z axis direction), it is possible to effectively prevent the movement of ejected material G such as the high-temperature gas or flame inside the pack case 200 in the upper direction (+Z axis direction) or the inflow into the upper space inside the pack case 200 during the thermal event described above.

[0101] Furthermore, the potting resin 400 can be filled into the spaces between the multiple cell assemblies 100. That is, the potting resin 400 can also be filled into the spaces between the partition members 300 surrounding the multiple cell assemblies 100. In this way, if a thermal event or damage occurs due to an abnormal condition in at least one specific battery cell 110 of the multiple cell assemblies 100, the potting resin 400, together with the partition members 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 can also act as an insulator to prevent current from flowing to the adjacent cell assembly 100 if a thermal event or damage occurs in the above-mentioned at least one specific battery cell 110.

[0102] The potting resin 400 can be continuously filled within the pack case 200 without any discontinuing or separating spaces, in the space above the cell assembly 100 (+Z axis direction), between the partition members 300 in the arrangement direction (X axis direction) of the cell assembly 100, and in the inner wall spaces on both sides (X axis direction) of the pack case 200. In this way, the potting resin 400 according to the embodiment of the present invention is continuously filled within the pack case 200 without discontinuity, thereby achieving uniform heat distribution without causing thermal dispersion deviations in the cell assembly 100 and improving the cooling performance of the battery pack 20.

[0103] The potting resin 400 may include a material having high specific heat performance. This allows the potting resin 400 to increase its thermal mass, thereby delaying the temperature rise of the battery cells 110 even under conditions such as rapid charging and discharging of the battery cells 110 in the cell assembly 100, and preventing a rapid temperature rise of the battery cells 110.

[0104] The potting resin 400 may include a material having high heat resistance. This allows the potting resin 400 to effectively prevent chain ignition or further thermal runaway due to heat propagation to adjacent cell assemblies 100 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.

[0105] The potting resin 400 may include a material having high flame retardancy. This allows the potting resin 400 to minimize 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 ejected material G that escapes from the vent portion 115 of the battery cell 110 during a thermal event from flowing upward (+Z axis direction) inside the pack case 200, and more reliably guides the ejection for the lower vent.

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

[0108] Since the battery pack 30 according to this embodiment is similar to the battery pack 10 of the above embodiment, redundant explanations of the same or similar components as in the above embodiment will be omitted, and the following discussion will focus on the differences from the above embodiment.

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

[0110] Since 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, redundant explanations 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 that of the above embodiment, so the following discussion will focus on the case body 510.

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

[0113] A storage section 514 can be formed in the bottom plate 512.

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

[0115] The housing portion 514 may include a fixing portion 516 and a stepped portion 517. The fixing portion 516 can accommodate the cell assembly 100 and the lower end of the partition member 300. The stepped portion 517 may be provided at a predetermined height between the cell assembly 100 surrounded by the partition member 300. On the other hand, the thickness of the fixing portion 516 may be thinner than that of the stepped portion 517 and the side plate 518. This is because the fixing portion 516 faces the vent portion 115 of the battery cell 110 of the cell assembly 100, allowing for a quicker release of the bottom plate 512 by easier fracture or melting during the thermal event.

[0116] The anchoring portions 516 and the stepped portions 517 may be arranged alternately along the longitudinal direction (X-axis direction) of the bottom plate 512. In other words, along the longitudinal direction (X-axis direction) of the bottom plate 512, one stepped portion 517 may be arranged between two anchoring portions 516, and one anchoring portion 516 may be arranged between two stepped portions 517. However, on the bottom plate 512, stepped portions 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 housing portion 514 provided on the bottom plate 512 of the pack case 500 allows the plurality of cell assemblies 100 and the partition members 300 to be more stably housed and supported within the pack case 200.

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

[0119] Since the battery pack 40 according to this embodiment is similar to the battery pack 10 in the above embodiment, redundant explanations of the same or similar components as in the above embodiment will be omitted, and the following discussion will focus on the differences from the above embodiment.

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

[0121] Since 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, redundant explanations 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 that of the above embodiment, so the following discussion will focus on the case body 610.

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

[0124] A vent guide 615 can be formed on the bottom plate 612.

[0125] The vent guide 615 ruptures or melts during the aforementioned thermal event, guiding ejected materials such as high-temperature gas or flames from the vent portion 115 of the battery cell 110 to be discharged to the underside (-Z axis direction) of the bottom plate 612.

[0126] Such a vent guide 615 is 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. Furthermore, the vent guide 615 may be formed at positions corresponding to the bottom of the vent portion 115 in the battery cell 110 of the plurality of cell assemblies 100. As a result, the bottom plate 612 may be formed with a structure having an uneven shape on the lower side (-Z axis direction) of the outer surface of the bottom (-Z axis direction) rather than on the upper side (+Z axis direction) of the inner surface of the bottom (-Z axis direction), due to the vent guide 615 provided at a predetermined depth on the lower side (-Z axis direction) of the outer surface of the bottom of the bottom plate 612.

[0127] In this embodiment, the vent guide 615 is in contact with the vent portion 115 of the battery cell 110 and has a relatively thin thickness at the bottom of the bottom plate 612, so that faster downward induced venting can be achieved in the event of the thermal event described above.

[0128] Furthermore, in the embodiment of the present invention, the portion of the bottom plate 612 between the vent guides 615 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. This effectively prevents ejected material that escapes from a specific vent guide 615 or particles generated by the fracture or melting of a specific vent guide 615 from dispersing to the adjacent vent guide 615. In other words, in one embodiment of the present invention, the uneven shape structure on the lower side (-Z axis direction) of the outer surface of the bottom plate 612 provided by the vent guides 615 effectively prevents the ejected material from dispersing to the left-right direction (X axis direction) of the bottom plate 612 when the ejected material is guided downward.

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

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

[0131] Since the battery pack 50 according to this embodiment is similar to the battery pack 10 of the above embodiment, redundant explanations of the same or similar components as in the above embodiment will be omitted, and the following discussion will focus on the differences from the above embodiment.

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

[0133] Since 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, redundant explanations 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 side plates 718. In this embodiment, the side plates 718 are similar to those in the above embodiment, so the following discussion 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 can support the plurality of cell assemblies 100 and the partition members 300. Such a first plate 713 is positioned directly opposite the vent portions 115 of the plurality of battery cells 110 and can have a relatively thin thickness for easier fracture or melting during the thermal events described above. For example, the first plate 713 may be thinner than the second plate 715, which will be described later.

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

[0139] Since the case cover 730 is substantially identical or similar to that of the embodiment described above, redundant explanations will be omitted below.

[0140] The guide channel 750 may be formed in the space between the first plate 713 and the second plate 715. The guide channel 750 can guide ejected materials G such as high-temperature gas and flames that 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 the vent unit 770, which will be described later. The guide channel 750 can also guide ejected materials G such as particles generated by the fracture or melting of the first plate 713 during a 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 ruptures or melts during the thermal event, allowing the ejected material G guided to the guide channel 750 to be discharged to the outside of the pack case 700. In addition to the structure that ruptures or melts above a predetermined temperature or pressure as described above, the vent unit 770 can also be provided in a way that it opens above a predetermined temperature or pressure, or that connects the inside and outside of the pack case 700. As a result, the vent structure of the vent unit 770 can be either a passive or active structure that can discharge the ejected material G. On the other hand, 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 fire extinguishing equipment or components for fire suppression outside the pack case 700. It goes without saying that multiple vent units 770 can be provided on the second plate 715.

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

[0143] Furthermore, in the battery pack 50 according to one embodiment of the present invention, the vent unit 770 provided on the second plate 715 can maximize the guiding ejection effect in a specific direction when venting with a downward directionality.

[0144] Figure 11 is a diagram illustrating automobile 1 according to one embodiment of the present invention.

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

[0146] Furthermore, it goes without saying that the battery packs 10, 20, 30, 40, and 50 according to the above embodiments of the present invention can be installed not only in the automobile 1 but also in other devices, mechanisms, and equipment such as energy storage systems that use secondary batteries.

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

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

[0149] Furthermore, through the various embodiments described above, it is possible to provide battery packs 10, 20, 30, 40, and 50, and an automobile 1 including such battery packs, which can achieve slimming and improve energy efficiency.

[0150] Although preferred embodiments of the present invention have been described above, the present invention is not limited to the specific embodiments described above. Various modifications can be made by a person with ordinary skill in the art to which the invention belongs, without departing from the gist of the invention as claimed in the claims. Moreover, such modifications should not be understood individually from the technical idea or outlook of the present invention. [Explanation of symbols]

[0151] 1. Automobile 10 Battery Packs 20 Battery Packs 30 Battery Packs 40 Battery Packs 50 Battery Packs 100 cell assembly 110 battery cells 115 Vent section 200 pack case 210 Case Body 212 Bottom Plate 218 Side Plate 230 Case Cover 300 Partition Member 400 potting resin 500 pack case 510 Case Body 512 Bottom Plate 514 Storage Unit 516 Safe Landing Section 517 Stepped section 518 Side Plate 530 Case Cover 600 pack case 610 Case Body 612 Bottom Plate 615 Bent Guide 618 Side Plate 630 Case Cover 700 pack case 710 Case Body 712 Bottom Plate 713 Plate 1 715 Second Plate 718 Side Plate 730 Case Cover 750 Guide channel 770 Vent Unit d1 First interval d2 2nd interval G ejecta W1 Storage width W2 Overall width

Claims

1. Multiple cell assemblies, each containing one or more battery cells and arranged in at least one row, A pack case for housing multiple cell assemblies, The pack case includes partitioning members made of a flexible material that partition the multiple cell assemblies and adhere closely to the multiple cell assemblies, The lower part of one or more of the aforementioned battery cells is provided with a vent section. A battery pack characterized in that the bottom of the pack case faces the vent portion and breaks or melts when gas or flames are discharged through the vent portion, thereby discharging the gas or flames to the outside of the pack case.

2. The partition member is The battery pack according to claim 1, characterized in that it is in close contact with the side surfaces of the plurality of cell assemblies in the direction of arrangement of the plurality of cell assemblies.

3. The partition member is The battery pack according to claim 1, characterized in that it is made of a fire-resistant rubber material.

4. The partition member is The battery pack according to claim 1, characterized in that it is made of an insulating rubber material.

5. The partition member is The battery pack according to claim 1, characterized in that it is arranged between the plurality of cell assemblies in the direction of arrangement of the plurality of cell assemblies.

6. The partition member is Multiple units are provided, corresponding to the number of the multiple cell assemblies. The multiple partition members are, The battery pack according to claim 1, characterized in that it is in close contact with both side surfaces of each of the aforementioned cell assemblies.

7. The multiple partition members are, The battery pack according to claim 6, characterized in that the plurality of cell assemblies are arranged at a predetermined distance apart from each other in the direction of arrangement.

8. The partition member is The battery pack according to claim 1, characterized in that the vent portion is exposed and the side portions of a plurality of cell assemblies are surrounded by it.

9. The aforementioned pack case is A case body supporting multiple cell assemblies and partition members, The battery pack according to claim 8, characterized in that it includes a case cover that is coupled to the case body and houses a plurality of the cell assemblies and the partition members.

10. The battery pack according to claim 9, characterized in that it includes a potting resin that fills the space between a plurality of cell assemblies and the case cover.

11. The potting resin is The battery pack according to claim 10, characterized in that it fills the spaces between a plurality of the cell assemblies.

12. An automobile characterized by including a battery pack according to any one of claims 1 to 11.

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