Battery pack and vehicle comprising same

Abstract

The present invention relates to a battery pack comprising: a plurality of battery cells; a pack case that has a plurality of frames each having a hollow formed therein, thereby accommodating the plurality of battery cells; and an endothermic material, which is interposed in the inner hollow of at least one of the respective frames, absorbs heat when a thermal event occurs in the battery cells so as to undergo a phase change, and then is movable toward the battery cells.

Description

Battery pack and automobile including the same

[0001] The present invention relates to a battery pack and an automobile including the same.

[0002] This application is a priority application for Korean Patent Application No. 10-2024-0194502 filed on December 23, 2024, and all contents disclosed in the specification and drawings of said application are incorporated into this application by reference.

[0003] Secondary batteries, which possess electrical characteristics such as high energy density and high applicability across product groups, are widely applied not only to portable devices but also to electric vehicles (EVs) or hybrid electric vehicles (HEVs) powered by electric sources. These secondary batteries are attracting attention as a new energy source for enhancing eco-friendliness and energy efficiency, not only for the primary advantage of drastically reducing the use of fossil fuels but also because they generate no by-products from energy use.

[0004] Currently, widely used types of secondary batteries include lithium-ion batteries, lithium-polymer batteries, nickel-cadmium batteries, nickel-hydrogen batteries, and nickel-zinc batteries. When a high output voltage is required, multiple battery cells are connected in series to form a battery module or battery pack. Additionally, to increase charge / discharge capacity, multiple battery cells are connected in parallel to form a battery module or battery pack. Therefore, the number of battery cells included in the battery module or pack can be varied depending on the required output voltage or charge / discharge capacity.

[0005] Meanwhile, since battery cells involve chemical reactions during charging and discharging, performance may degrade if used in environments higher than the optimal temperature; furthermore, if thermal control is not maintained at the appropriate temperature, there is a constant risk of unexpected ignition or explosion. In particular, if a thermal event such as thermal runaway occurs within a battery pack containing multiple battery modules, it is extremely dangerous because high-temperature gases or flames ejected from the internal battery cells can transfer to adjacent modules, potentially leading to a chain reaction of explosions.

[0006] Therefore, there is a need to develop a structure that can prevent heat from being transferred to adjacent battery modules in the event of thermal runaway in a battery module.

[0007] Therefore, the problem that the present invention aims to solve is to provide a battery pack with improved safety and reliability by preventing or suppressing the propagation of thermal runaway between battery modules by minimizing the thermal energy received by adjacent battery modules when thermal runaway occurs in a battery module.

[0008] In addition, another problem that the present invention aims to solve is to provide a vehicle including such a battery pack.

[0009] However, the problems that the present invention aims to solve are not limited to those described above, and other unmentioned problems will be clearly understood by those skilled in the art from the description of the invention below.

[0010] To solve the above problem, the present invention provides a battery pack comprising: a plurality of battery cells; a pack case configured to accommodate the plurality of battery cells by being provided with a plurality of frames having a hollow formed therein; and an endothermic material interposed in the hollow of at least one of the plurality of frames, configured to be movable toward the battery cell side after absorbing heat upon the occurrence of a thermal event of the battery cell and changing its properties.

[0011] At least one of the plurality of frames may have a through hole formed therein configured to allow the heat-absorbing material, which has been changed on the inner surface, to move inward.

[0012] A battery pack according to one embodiment of the present invention may further include a module case that accommodates the plurality of battery cells by grouping them and has a plurality of venting holes formed on one side.

[0013] The modified heat-absorbing material can be configured to flow into the interior of the module case through the venting hole.

[0014] The above pack case is configured to accommodate the battery cell and may have a first frame in which the heat-absorbing material is interposed in the internal hollow.

[0015] The above pack case is configured to surround the side of the battery cell and may have a second frame in which the heat-absorbing material is interposed in the internal hollow.

[0016] The above pack case is configured to partition the space between the battery cells and may have a third frame in which the heat-absorbing material is interposed in the internal hollow.

[0017] The above pack case is provided on the upper part of the battery cell and may have a fourth frame in which a passage is formed in the internal hollow through which the changed heat-absorbing material can move.

[0018] A battery pack according to one embodiment of the present invention may further include an insertion member configured to be at least partially inserted into the through hole and separated from the through hole by the changed heat-absorbing material.

[0019] A battery pack according to one embodiment of the present invention may further include a fireproof sheet configured to cover the inner surface of the pack case.

[0020] The above fireproof sheet may be provided by being adhered to the inner surface of the pack case by an adhesive member.

[0021] The above fireproof sheet may be configured to be separated from the inner side of the pack case by the insertion member when a thermal event occurs in the battery cell, so as to cover the battery cell.

[0022] A battery pack according to one embodiment of the present invention may further include an inner plate spaced inward from the inner surface of the pack case; and a fire extinguishing material interposed between the inner surface of the pack case and the inner plate.

[0023] An inlet hole may be formed in the inner plate above to allow the extinguishing material to flow into the battery cell side.

[0024] The inner plate may cover the inlet hole and be provided with a cover member configured to rupture by the pressure of the extinguishing material.

[0025] And, the present invention provides an automobile characterized by including a battery pack according to the present invention.

[0026] According to one aspect of the present invention, in a situation of thermal runaway of a battery module, an endothermic material interposed inside a pack case can absorb heat generated in a battery cell or battery module as it changes. As a result, the temperature of the battery module can be lowered without a separate power device or control device.

[0027] Accordingly, according to one aspect of the present invention, when thermal runaway occurs in a battery module, the thermal energy received by adjacent battery modules can be minimized. As a result, the propagation of thermal runaway between battery modules is prevented or suppressed, thereby ensuring the safety and reliability of the battery pack.

[0028] In addition, according to another aspect of the present invention, when thermal runaway occurs in a battery module, a fire-resistant sheet is configured to cover the battery module, thereby extinguishing flames generated in the battery module.

[0029] In addition, according to another aspect of the present invention, when thermal runaway occurs in a battery module, high-temperature gas or flames emitted outside the battery module can be prevented from entering into another battery module.

[0030] In addition, according to another aspect of the present invention, events resulting from thermal runaway phenomena in a battery pack or a device equipped with a battery pack, such as fire or explosion, can be prevented or delayed.

[0031] In addition to the above, the present invention may have various other effects, which are described in each embodiment, or effects that can be easily inferred by those skilled in the art, etc., will be omitted.

[0032] The following drawings attached to this specification illustrate preferred embodiments of the present invention and serve to further enhance understanding of the technical concept of the present invention together with the detailed description of the invention provided below; therefore, the present invention should not be interpreted as being limited only to the matters described in such drawings.

[0033] FIG. 1 is an overall perspective view of a battery pack according to one embodiment of the present invention.

[0034] FIG. 2 is an exploded perspective view of a battery pack according to one embodiment of the present invention.

[0035] FIG. 3 is a cross-sectional view of a battery pack according to one embodiment of the present invention. For example, FIG. 3 may be a drawing showing the cross-section I-I' of FIG. 1.

[0036] FIG. 4 is a cross-sectional view of a battery pack according to one embodiment of the present invention when a thermal event occurs.

[0037] FIG. 5 is a schematic perspective view of a battery module included in a battery pack according to one embodiment of the present invention.

[0038] FIG. 6 is a cross-sectional view of a battery pack according to one embodiment of the present invention, viewed from above.

[0039] FIG. 7 is a bottom perspective view of a fourth frame included in a battery pack according to one embodiment of the present invention.

[0040] FIG. 8 is a cross-sectional view of a battery pack according to another embodiment of the present invention.

[0041] FIG. 9 is a cross-sectional view of a battery pack when a thermal event occurs according to another embodiment of the present invention.

[0042] FIG. 10 is a cross-sectional view of a battery pack according to another embodiment of the present invention.

[0043] FIG. 11 is a cross-sectional view of a battery pack when a thermal event occurs according to another embodiment of the present invention.

[0044] FIG. 12 is a cross-sectional view of a battery pack according to another embodiment of the present invention.

[0045] FIG. 13 is a cross-sectional view of a battery pack when a thermal event occurs according to another embodiment of the present invention.

[0046] FIG. 14 is a schematic perspective view of a vehicle including a battery pack according to one embodiment of the present invention.

[0047] Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the attached drawings. Prior to this, terms and words used in this specification and claims should not be interpreted as being limited to their ordinary or dictionary meanings, but should be interpreted in a meaning and concept consistent with the technical spirit of the present invention, based on the principle that the inventor can appropriately define the concept of the terms to best describe his invention.

[0048] Therefore, the embodiments described in this specification and the configurations illustrated in the drawings are merely the most preferred embodiments of the present invention and do not represent all of the technical ideas of the present invention; thus, it should be understood that various equivalents and modifications that can replace them may exist at the time of filing this application.

[0049] In addition, the present invention includes various embodiments. For each embodiment, redundant descriptions of substantially identical or similar configurations are omitted, and the focus is on the differences.

[0050] Meanwhile, although terms indicating directions such as up, down, left, right, front, and back may be used in the present invention, these terms are used merely for convenience of explanation and may vary depending on the position of the object or the position of the observer, as is obvious to those skilled in the art of the present invention.

[0051] For example, in an embodiment of the present invention, the X-axis direction shown in the drawing may mean the left-right direction, the Y-axis direction may mean the front-back direction perpendicular to the X-axis direction on the horizontal plane (XY plane), and the Z-axis direction may mean the up-down direction (vertical direction) perpendicular to both the X-axis direction and the Y-axis direction.

[0052]

[0053] FIG. 1 is an overall perspective view of a battery pack according to an embodiment of the present invention, and FIG. 2 is an exploded perspective view of a battery pack according to an embodiment of the present invention. FIG. 3 is a cross-sectional view of a battery pack according to an embodiment of the present invention. For example, FIG. 3 may be a drawing showing the cross-section along I-I' of FIG. 1. FIG. 4 is a cross-sectional view of a battery pack according to an embodiment of the present invention when a thermal event occurs.

[0054] Referring to FIGS. 1 to 4, a battery pack (1) according to one embodiment of the present invention includes a battery cell (100), a pack case (200), and an endothermic material (M).

[0055] First, referring to FIG. 2, a plurality of battery cells (100) may be included. Although not shown in the drawing, these plurality of battery cells (100) may include an electrode assembly, a cell case that accommodates the electrode assembly, and an electrode lead that is connected to the electrode assembly and extends outward from the cell case to function as an electrode terminal. At this time, the plurality of battery cells (100) may be electrically connected to each other.

[0056] The battery cell (100) may be a pouch-type secondary battery. The cell case of such a pouch-type secondary battery may be configured in the form of a pouch in which a metal layer made of aluminum is interposed between polymer layers.

[0057] A plurality of battery cells (100) can be arranged side by side in the front-back direction (X-axis direction) while standing upright in the vertical direction (Z-axis direction), as shown in FIG. 2.

[0058] Meanwhile, the present invention is not limited by the specific type or shape of such battery cell (100), and various battery cells (100) known at the time of filing the present invention may be employed to constitute the battery pack (1) of the present invention. In this embodiment, a pouch-type secondary battery with high energy density and easy stacking is used as shown in the drawing, but it is understood that cylindrical or prismatic secondary batteries may also be applied as battery cells (100).

[0059] The pack case (200) may be configured to accommodate a plurality of battery cells (100). The pack case (200) may be provided in a box shape including a plurality of beams or a plurality of frames. The pack case (200) may have a receiving space formed to accommodate a plurality of battery cells (100). The receiving space is an empty space and may be provided in a shape capable of accommodating the battery cells (100) inside.

[0060] The pack case (200) may be made of a material capable of ensuring mechanical strength, such as steel or SUS metal or plastic, or may include such a material, in order to safely protect the battery cell (100) housed inside.

[0061] Referring to FIG. 3, at least one of the multiple frames of the pack case (200) may have a hollow formed inside. An endothermic material (M) may be interposed in the hollow of at least one of these multiple frames. This endothermic material (M) may be configured to absorb heat. The endothermic material (M) may be configured to change its material properties by absorbing heat. For example, the endothermic material (M) may have a material that generates a extinguishing substance, such as by changing its state like steaming, change, or sublimation at room temperature or in an environment above a certain temperature, or through a chemical reaction process, or may be composed of such a material.

[0062] For example, the endothermic substance (M) is provided as a solid at room temperature and can change into a gas when it absorbs heat and reaches a certain temperature or higher. For instance, the endothermic substance (M) may include carbon dioxide in a solid state.

[0063] As another example, the endothermic material (M) may be liquid at room temperature. For instance, the endothermic material (M) may include water or a phase change material (PCM).

[0064] Specifically, referring to FIG. 4, the heat-absorbing material (M) can be configured to move toward the battery cell (100) after absorbing heat when a thermal event occurs in the battery cell (100) and changing its properties. The changed heat-absorbing material (M') may be a gas. Thus, the changed heat-absorbing material (M') can move toward the battery cell (100) and absorb heat from the battery cell (100) to lower the temperature.

[0065] According to this embodiment of the present invention, when an event such as thermal runaway of the battery cell (100) occurs, the heat of the battery cell (100) can be absorbed through endothermic reactions such as evaporation and sublimation. Furthermore, according to the above embodiment of the present invention, as the endothermic material (M) changes, it absorbs heat such as venting gas and flames, thereby lowering the temperature of high-temperature venting gas or active material particles. Thus, the temperature of the battery cell (100) can be lowered without a separate power device or control device.

[0066] Accordingly, according to the above embodiment of the present invention, when thermal runaway occurs in a battery cell (100), the thermal energy received by an adjacent battery cell (100) can be minimized. As a result, the propagation of thermal runaway within the battery pack (1) is prevented or suppressed, thereby ensuring the safety and reliability of the battery pack (1).

[0067]

[0068] Meanwhile, referring to FIGS. 3 and 4, a through hole (TH) may be formed in the pack case (200). The through hole (TH) may be formed in at least one of the multiple frames. The through hole (TH) may be formed on the inner surface of the pack case (200). The through hole (TH) may be configured to allow the changed heat-absorbing material (M') to move inward. That is, the through hole (TH) may be configured to connect the receiving space of the battery cell (100) and the hollow of the frame.

[0069] Multiple through holes (TH) may be provided. Multiple through holes (TH) may be provided at regular intervals from each other in the horizontal direction (X-axis, Y-axis direction).

[0070] According to the above embodiment of the present invention, the modified heat-absorbing material (M') can move toward the battery cell (100) through the through hole (TH) to directly lower the temperature of the battery cell (100). In addition, according to the above embodiment of the present invention, as the modified heat-absorbing material (M') moves inward, it can weaken the pressure attempting to discharge venting gas or flames outward. As a result, the transfer of heat to other battery cells (100) is minimized, thereby suppressing or preventing the propagation of thermal runaway within the battery pack (1).

[0071]

[0072] FIG. 5 is a schematic perspective view of a battery module included in a battery pack according to one embodiment of the present invention.

[0073] Meanwhile, referring to FIG. 5, a plurality of battery cells (100) can be modularized into one or more battery modules (10). That is, the battery pack (1) according to the present invention may include one or more battery modules (10). And, a plurality of battery cells (100) may be included as components of one or more battery modules (10). At this time, the multiple battery cells (100) included inside the battery module (10) may be electrically connected to each other.

[0074] Furthermore, a plurality of battery modules (10) may be provided inside the pack case (200). That is, the battery pack (1) according to the present invention includes a plurality of battery modules (10), and a plurality of battery cells (100) included in the battery pack (1) may be divided and included in the plurality of battery modules (10).

[0075] A plurality of battery modules (10) may be arranged along at least one direction inside the pack case (200). For example, as in the embodiment shown in FIG. 2, a plurality of battery modules (10) may be arranged in three rows along the front-rear direction of the pack case (200) and in two columns along the left-right direction of the pack case (200), so that a total of six battery modules (10) are provided.

[0076] In particular, the battery pack (1) according to the present invention may include a module case (11). The module case (11) may be configured to have an empty space formed inside to accommodate at least some of a plurality of battery cells (100) in the internal space. In particular, the module case (11) may be included for each battery module (10) to group a plurality of battery cells (100) into multiple battery modules (10) and may serve as a boundary that physically limits the internal space of each battery module (10).

[0077] Additionally, although not shown in the drawing, the battery module (10) may include a busbar assembly and / or module terminals electrically connected to a plurality of battery cells (100) housed inside.

[0078] A venting hole (VH) may be formed in the module case (11). The venting hole (VH) may be configured to allow venting gas generated from a battery cell (100) housed inside the module case (11) to be discharged to the outside of the module case (11).

[0079] Specifically, the venting hole (VH) can enable directional venting in a specific direction. For example, as shown in FIG. 5, a venting hole (VH) is formed on the upper surface of the module case (11), and directional venting toward the upper side of the battery module (10) can be enabled through the venting hole (VH). The venting hole (VH) may be provided in multiple numbers and may be provided at regular intervals from each other in the horizontal direction (X-axis, Y-axis direction).

[0080] According to the above embodiment of the present invention, in a situation where one of the battery cells (100) undergoes thermal runaway and generates gas, etc., the gas, etc. can be rapidly directionally vented from the module case (11) in a specific direction.

[0081] In this way, the venting hole (VH) provided on the upper surface of the module case (11) can be configured to discharge gas or flame generated inside the battery module (10) to the outside of the battery module (10) when thermal runaway of the battery module (10) occurs. The remaining part of the module case (11) excluding the venting hole (VH) is sealed, and the gas or flame can be discharged in a straight line toward the venting hole (VH).

[0082] According to the above embodiment of the present invention, even if a thermal event occurs at any location of the battery cell (100), the gas or flame generated in the battery cell (100) is discharged to the outside of the battery module (10) through specific venting holes (VH) provided on the upper part of the battery cell (100), thereby facilitating venting.

[0083] Meanwhile, referring again to FIG. 4, the changed heat-absorbing material (M') can be configured to flow into the interior of the module case (11) through the venting hole (VH). When a thermal event occurs in the battery cell (100), the heat-absorbing material (M) absorbs heat and changes into a gas, and then flows into the interior of the module case (11) through the venting hole (VH).

[0084] At this time, the frame of the pack case (200) in which the through hole (TH) is formed may be configured to face one side of the module case (11) in which the venting hole (VH) is formed. That is, the through hole (TH) may be configured to face the venting hole (VH). The number or location of the through holes (TH) may be configured to correspond to the number or location of the venting holes (VH).

[0085] According to the above embodiment of the present invention, the modified heat-absorbing material (M) can move to the receiving space of the battery cell (100) through the through hole (TH) and then move directly to the module case (11) through the venting hole (VH). This allows the temperature of the battery cell (100) to be lowered more quickly.

[0086] In addition, according to the above embodiment of the present invention, as the changed heat-absorbing material (M') moves into the interior of the module case (11), the pressure to discharge venting gas or flames to the outside through the venting hole (VH) can be weakened. Therefore, thermal runaway between battery modules (10) can be suppressed or prevented.

[0087]

[0088] FIG. 6 is a cross-sectional view of a battery pack according to one embodiment of the present invention viewed from above, and FIG. 7 is a bottom perspective view of a fourth frame included in a battery pack according to one embodiment of the present invention.

[0089] Meanwhile, referring to FIGS. 6 and FIGS. 7 together with FIGS. 1 to 4, as described above, a pack case (200) according to one embodiment of the present invention may have a plurality of frames. More specifically, the pack case (200) may include a first frame (210) and a second frame (220).

[0090] The first frame (210) can form the lower surface of the pack case (200) and can be provided in the shape of a square plate. Additionally, the first frame (210) can be configured so that a plurality of battery cells (100) are seated on its upper surface. Furthermore, the first frame (210) can be provided with a flat upper surface so that a plurality of battery modules (10) are stably seated.

[0091] Referring to FIG. 3, the first frame (210) may have a hollow formed inside. That is, a hollow is formed inside the first frame (210), and an endothermic material (M) may be interposed in the hollow.

[0092] According to the above embodiment, more heat can be applied to the heat-absorbing material (M) that is in direct contact with the battery cell (100), so that the heat-absorbing material (M) can absorb heat and rapidly change and move toward the battery cell (100).

[0093] The second frame (220) may extend upward from each corner of the first frame (210). The second frame (220) may be provided with a plurality of unit walls to surround a plurality of battery cells (100). More specifically, the plurality of second frames (220) may each be provided with a right wall located at the -Y direction end of the first frame (210), a rear wall located at the +X direction end, a left wall located at the +Y direction end, and a front wall located at the -X direction end, thereby forming the side of the pack case (200).

[0094] Referring to FIG. 6, the second frame (220) may have a hollow formed inside. That is, a hollow is formed inside the second frame (220), and an endothermic material (M) may be interposed in the hollow.

[0095] According to the above embodiment, more heat can be applied to the heat-absorbing material (M) that is in direct contact with the battery cell (100), so that the heat-absorbing material (M) can absorb heat and rapidly change and move toward the battery cell (100).

[0096] The pack case (200) may be provided with a venting section. The venting section may be configured to discharge the discharge generated from the battery cell (100) to the outside of the pack case (200). The venting section may be provided, for example, in the second frame (220).

[0097] The venting portion may be provided in the form of a hole penetrating between the inside and outside of the pack case (200). Alternatively, the venting portion may be provided in the form of a venting device configured to be mounted in the hole of the pack case (200) and activated when discharge occurs inside the pack case (200).

[0098] Meanwhile, the number or location of the venting section described based on the embodiment of FIG. 2 is merely an example, and it goes without saying that it can be changed to various other numbers or locations.

[0099] The pack case (200) may be provided with a third frame (230). The third frame (230) may be provided to partition between a plurality of battery cells (100). For example, the third frame (230) may be formed in the shape of a partition extending long in the front-rear direction and interposed between battery modules (10) arranged adjacently in the left-right direction. Additionally, the third frame (230) may be formed in the shape of a partition extending long in the left-right direction and interposed between battery modules (10) arranged adjacently in the front-rear direction.

[0100] The third frame (230) may be provided to protrude upward above the battery cell (100). According to this embodiment, heat or flames can be prevented from directly moving between the battery cells (100) separated by the storage space of the third frame (230).

[0101] Referring to FIG. 6, a hollow can be formed inside this third frame (230). That is, a hollow can be formed inside the third frame (230) and an endothermic material (M) can be interposed in the hollow.

[0102] According to the above embodiment, more heat can be applied to the heat-absorbing material (M) that is in direct contact with the battery cell (100), so that the heat-absorbing material (M) can absorb heat and rapidly change and move toward the battery cell (100).

[0103] The fourth frame (240) may be configured to cover the upper portion of a plurality of battery cells (100). The fourth frame (240) may be configured to cover the open upper portion of the pack case (200). The fourth frame (240) may be coupled to the second frame (220). The fourth frame (240) protects components housed inside the pack case (200), such as battery cells (100), and prevents discharge from these battery cells (100) from being discharged to the outside of the pack case (200), particularly to the top.

[0104] Referring to FIG. 7, the fourth frame (240) may have a hollow formed inside. The fourth frame (240) may have a passage (path indicated as P in FIG. 4) formed in the internal hollow through which the modified endothermic material (M') can move. The hollow of the fourth frame (240) may be configured to communicate with at least one of the hollows of the first frame (210) to the third frame (230).

[0105] At this time, the fourth frame (240) may be configured to face the venting hole (VH). Additionally, the fourth frame (240) may have a through hole (TH) on its inner surface (240a).

[0106] Specifically, referring to the embodiment illustrated in FIG. 4, when a thermal event occurs in the battery cell (100), the heat-absorbing material (M) interposed inside at least one of the first frame (210) to the third frame (230) absorbs heat and its properties change, after which the changed heat-absorbing material (M') can move into the internal hollow of the fourth frame (240). Additionally, it can move toward the battery cell (100) through the through hole (TH) of the fourth frame (240).

[0107] According to the above embodiment of the present invention, the space interposed before the heat-absorbing material (M) absorbs heat and the space where the changed heat-absorbing material (M') can move can be separated. Thereby, sufficient time can be provided for the heat-absorbing material (M) to absorb heat and for the properties to change.

[0108]

[0109] Meanwhile, referring to FIGS. 3, 4 and 6, the pack case (200) may be provided with a partition (W). The partition (W) may be provided in at least one of the third frame (230) and the fourth frame (240). The partition (W) may be configured to divide the hollow space inside the frame into a plurality of spaces. The partition (W) may be provided inside the third frame (230) which is provided between a plurality of battery modules (10).

[0110] The partition (W) may be configured to separate the battery modules (10) individually. Any one battery module (10) may be configured to be surrounded by an endothermic material (M) surrounded by the partition (W) within the first frame (210), the second frame (220), and the third frame (230).

[0111] According to the above embodiment of the present invention, a partition (W) is provided in the internal hollow of a frame so that a plurality of battery modules (10) are partitioned. Consequently, when a thermal event occurs in any of the battery modules (10), only the heat-absorbing material (M) surrounding each battery module (10) absorbs heat, thereby changing the compatibility. Thus, when a thermal runaway occurs in any of the battery modules (10), a rapid heat-absorbing reaction occurs around the battery module (10) where the event occurred, allowing the heat of the battery module (10) to be absorbed.

[0112] According to the above embodiment of the present invention, heat propagation to other battery modules (10) can be minimized so as not to affect other battery modules (10). Accordingly, heat runaway propagation within the battery pack (1) is prevented or suppressed, thereby ensuring the safety and reliability of the battery pack (1).

[0113]

[0114] FIG. 8 is a cross-sectional view of a battery pack according to another embodiment of the present invention, and FIG. 9 is a cross-sectional view of a battery pack according to another embodiment of the present invention when a thermal event occurs.

[0115] Referring to FIGS. 8 and 9, a battery pack (1) according to one embodiment of the present invention may further include an insertion member (300). The insertion member (300) may be configured to cover a through hole (TH). The insertion member (300) may be configured to be inserted at least partially into the through hole (TH). The insertion member (300) may be configured in the form of a plug that blocks the through hole (TH).

[0116] The insertion member (300) may be provided in multiple numbers and may be provided for each through hole (TH). The insertion member (300) may be provided on the inner surface (240a) of the fourth frame (240) where the through hole (TH) is formed.

[0117] This insertion member (300) can be configured to be separated from the through hole (TH) when a thermal event occurs in the battery cell (100). That is, the insertion member (300) can be configured to open the through hole (TH) when a thermal event occurs in the battery cell (100).

[0118] As an example, as in the embodiment illustrated in FIG. 9, the insertion member (300) may be configured to be completely separated from the through hole (TH) by the changed heat-absorbing material (M'). Specifically, the insertion member (300) may be configured to move inward by the vapor pressure of the changed heat-absorbing material (M') and be separated from the through hole (TH).

[0119] Alternatively, as another example, the insert member (300) may be configured to be melted by heat such as venting gas.

[0120] Referring to FIG. 9, among the plurality of insertion members (300), only the insertion member (300) provided on the side of the battery module (10) where a thermal event occurred can be configured to be separated from the through hole (TH). As the insertion member (300) provided on the upper side of the battery module (10) where a thermal event occurred is separated from the through hole (TH), the heat-absorbing material (M') that has changed can move to the side of the battery module (10) through the through hole (TH).

[0121] Additionally, the remaining insertion member (300) provided on the side of the adjacent battery module (10) is not separated from the through hole (TH), so it can be configured so that venting gas or flames do not flow into the side of the other battery module (10).

[0122] According to the above embodiment of the present invention, when thermal runaway occurs in a battery cell (100), the temperature of each battery module (10) can be lowered individually, thereby minimizing heat propagation to the battery cell (100) provided in another battery module (10). That is, according to the above embodiment of the present invention, even if a thermal event occurs in any battery module (10), it is possible to ensure that other battery modules (10) are not affected. Accordingly, the propagation of thermal runaway within the battery pack (1) is prevented or suppressed, thereby ensuring the safety and reliability of the battery pack (1).

[0123]

[0124] FIG. 10 is a cross-sectional view of a battery pack according to another embodiment of the present invention, and FIG. 11 is a cross-sectional view of a battery pack according to another embodiment of the present invention when a thermal event occurs.

[0125] Referring to FIGS. 10 and 11, a battery pack (1) according to one embodiment of the present invention may further include a fireproof sheet. The fireproof sheet (400) may be interposed on the inner surface of the pack case (200). The fireproof sheet (400) may be configured to cover the inner surface of the pack case (200). For example, the fireproof sheet (400) may be interposed on the inner surface (240a) of the fourth frame (240). The fireproof sheet (400) may be configured to cover the through hole (TH) from the inside.

[0126] The fire-resistant sheet (400) may be provided in the form of a thin sheet. The fire-resistant sheet (400) may be provided with a material having excellent fire resistance. For example, the fire-resistant sheet (400) may be provided as a fire-resistant sheet. The fire-resistant sheet may be provided with a special fiber material designed to suppress damage caused by fire or prevent the spread of flames. As an example, the fire-resistant sheet (400) may be provided with silica fiber, glass fiber, Kevlar (Aramid), or a specially coated cloth.

[0127] According to the above embodiment of the present invention, as the fireproof sheet (400) is provided, even if a thermal event occurs in one battery module (10), the transfer of venting gas, flame, heat, etc. to another battery module (10) can be further suppressed.

[0128] Referring to FIG. 10, a fireproof sheet (400) may be provided by being adhered to the inner surface of a pack case (200) by an adhesive member (500). The adhesive member (500) may be provided with an adhesive or the like. The fireproof sheet (400) may be adhered to the inner surface (240a) of a fourth frame (240) by the adhesive member (500). Furthermore, the fireproof sheet (400) may also be adhered to an insertion member (300).

[0129] Meanwhile, referring to FIG. 11, the fireproof sheet (400) can be configured to be separated from the inner side of the pack case (200) when a thermal event occurs in the battery cell (100). Specifically, as the insertion member (300) moves inward due to the vapor pressure of the changed heat-absorbing material (M), the fireproof sheet (400) can be separated from the inner side of the pack case (200). Furthermore, the adhesive member (500) can be melted by heat so that the fireproof sheet (400) can be separated more quickly from the inner side of the pack case (200).

[0130] The separated fireproof sheet (400) may be configured to cover the battery cell (100) or the battery module (10). The fireproof sheet (400) may be configured to cover the upper surface of the module case (11). The fireproof sheet (400) may be configured to cover the venting hole (VH).

[0131] According to the above embodiment of the present invention, as the fire-resistant sheet (400) is separated from the inner side of the pack case (200) to cover the battery cell (100) to the battery module (10), the oxygen supply is cut off, thereby inducing suffocation extinguishing. As a result, the flame can be suppressed or extinguished.

[0132] In addition, according to the above embodiment of the present invention, as the separated fireproof sheet (400) covers the venting hole (VH), the discharge of flames, etc. to the outside of the module case (11) through the venting hole (VH) can be suppressed. As a result, the propagation of thermal runaway between battery modules (10) is prevented or suppressed, thereby ensuring the safety and reliability of the battery pack (1).

[0133]

[0134] FIG. 12 is a cross-sectional view of a battery pack according to another embodiment of the present invention, and FIG. 13 is a cross-sectional view of a battery pack according to another embodiment of the present invention when a thermal event occurs.

[0135] Referring to FIGS. 12 and 13, a battery pack (1) according to one embodiment of the present invention may further include an inner plate (600). The inner plate (600) may be provided on the inner side of the pack case (200). The inner plate (600) may be provided spaced inward from the inner surface of the pack case (200). For example, the inner plate (600) may be provided spaced inward from the inner surface (240a) of the fourth frame (240).

[0136] Additionally, a battery pack (1) according to one embodiment of the present invention may further include a fire extinguishing material (E). The fire extinguishing material (E) may be interposed between the inner surface of the pack case (200) and the inner plate (600). For example, the fire extinguishing material (E) may be filled into the space between the inner surface (240a) of the fourth frame (240) and the inner plate (600).

[0137] The extinguishing substance (E) may be configured to perform the action of suppressing or extinguishing a flame. The extinguishing substance (E) may be prepared in a liquid state at room temperature. For example, the extinguishing substance (E) may include water.

[0138] An inlet hole (610) may be formed in the inner plate (600). The inlet hole (610) may be provided in the form of a hole penetrating a part of the inner plate (600). Multiple inlet holes (610) may be provided. Multiple inlet holes (610) may be spaced apart along the horizontal direction.

[0139] The inlet hole (610) can be configured to communicate the space between the inner plate (600) and the pack case (200) with the receiving space. Accordingly, the inlet hole (610) can be configured to allow a fire extinguishing substance (E) to flow into the battery cell (100). The fire extinguishing substance (E) interposed between the inner plate (600) and the inner surface of the pack case (200) can be configured to be sprayed into the battery cell (100) through the inlet hole (610).

[0140] The inner plate (600) may be provided with a cover member (620). The cover member (620) may be configured to cover the inlet hole (610). The cover member (620) may be provided on the inner surface of the inner plate (600).

[0141] Referring to FIG. 13, the cover member (620) may be configured to open the inlet hole (610) when a thermal event occurs in the battery cell (100). For example, the cover member (620) may be configured to melt due to heat. Alternatively, the cover member (620) may be configured to rupture due to pressure such as a fire extinguishing substance (E). Accordingly, the fire extinguishing substance (E) may be sprayed toward the battery cell (100) through the opened inlet hole (610).

[0142] More specifically, as the insertion member (300) moves inward due to the vapor pressure of the changed heat-absorbing material (M'), a force may be generated to move the extinguishing material (E) inward as the pressure inside the space between the inner plate (600) and the pack case (200) decreases. Accordingly, the cover member (620) covering the inlet hole (610) may rupture due to the pressure of the extinguishing material (E).

[0143] Referring to FIG. 13, among the plurality of cover members (620), only the cover member (620) provided on the side of the battery module (10) where a thermal event occurred may be configured to rupture. As the cover member (620) provided on the upper side of the battery module (10) where a thermal event occurred ruptures, a fire extinguishing substance (E) may be sprayed toward the battery module (10) through the open inlet hole (610).

[0144] In addition, the remaining cover member (620) provided on the side of the adjacent battery module (10) is not ruptured, so it can be configured so that venting gas or flames do not flow into the side of the other battery module (10).

[0145] According to the above embodiment of the present invention, when thermal runaway occurs in a battery cell (100), the temperature of each battery module (10) can be lowered individually, thereby minimizing heat propagation to the battery cell (100) provided in another battery module (10). That is, according to the above embodiment of the present invention, even if a thermal event occurs in any battery module (10), it is possible to ensure that other battery modules (10) are not affected. Accordingly, the propagation of thermal runaway within the battery pack (1) is prevented or suppressed, thereby ensuring the safety and reliability of the battery pack (1).

[0146]

[0147] FIG. 14 is a schematic perspective view of a vehicle including a battery pack according to one embodiment of the present invention.

[0148] Referring to FIG. 14, a vehicle (3) according to one embodiment of the present invention may include one or more battery packs (1) according to one embodiment of the present invention. The vehicle (3) according to the present invention may be, for example, an electric vehicle, a hybrid vehicle, or a plug-in hybrid vehicle. The vehicle (3) includes four-wheeled vehicles and two-wheeled vehicles. The vehicle (3) may operate by receiving power from a battery pack (1) according to one embodiment of the present invention.

[0149]

[0150] Although the present invention has been described above by limited embodiments and drawings, the present invention is not limited thereto, and it is obvious that various modifications and variations are possible within the scope of the technical spirit of the present invention and the equivalent scope of the claims described below by those skilled in the art to which the present invention belongs.

Claims

1. Multiple battery cells; A pack case configured to accommodate the plurality of battery cells, provided with a plurality of frames having a hollow formed inside; and A battery pack characterized by including an endothermic material interposed in the internal hollow of at least one of the plurality of frames, configured to absorb heat upon the occurrence of a thermal event of the battery cell and, after its properties are changed, to be movable toward the battery cell.

2. In Paragraph 1, At least one of the above plurality of frames is A battery pack characterized by having a through hole formed on the inner surface configured to allow the heat-absorbing material, which has been changed, to move inward.

3. In Paragraph 1, A battery pack characterized by further including a module case that accommodates a plurality of battery cells grouped together and has a plurality of venting holes formed on one side.

4. In Paragraph 3, A battery pack characterized by being configured such that the changed heat-absorbing material is introduced into the interior of the module case through the venting hole.

5. In Paragraph 1, The above pack case is A battery pack characterized by having a first frame configured to accommodate the battery cell and having the heat-absorbing material interposed in the internal hollow.

6. In Paragraph 1, The above pack case is A battery pack characterized by having a second frame configured to surround the side of the battery cell and having the heat-absorbing material interposed in the internal hollow.

7. In Paragraph 1, The above pack case is A battery pack characterized by having a third frame configured to partition the space between the battery cells and having the heat-absorbing material interposed therein in the internal hollow.

8. In Paragraph 1, The above pack case is A battery pack characterized by having a fourth frame provided on the upper part of the battery cell, wherein a passage is formed in the internal hollow through which the heat-absorbing material that has been changed can move.

9. In Paragraph 2, A battery pack characterized by further including an insertion member configured to be at least partially inserted into the through hole and separated from the through hole by the changed heat-absorbing material.

10. In Paragraph 9, A battery pack characterized by further including a fireproof sheet configured to cover the inner surface of the pack case.

11. In Paragraph 10, A battery pack characterized in that the above-mentioned fireproof sheet is provided by being adhered to the inner surface of the pack case by an adhesive member.

12. In Paragraph 10, A battery pack characterized in that the above-mentioned fireproof sheet is configured to be separated from the inner side of the pack case by the insertion member to cover the battery cell when a thermal event occurs in the battery cell.

13. In Paragraph 9, An inner plate provided spaced inward from the inner surface of the above-mentioned pack case; and A battery pack characterized by further including a fire extinguishing material interposed between the inner surface of the pack case and the inner plate.

14. In Paragraph 13, The inner plate above A battery pack characterized by having an inlet hole formed to allow the above-mentioned extinguishing material to flow into the battery cell side.

15. In Paragraph 14, The above inner plate is A battery pack characterized by having a cover member that covers the inlet hole and is configured to rupture by the pressure of the extinguishing material.

16. An automobile comprising a battery pack according to any one of paragraphs 1 through 15.

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