Battery pack and automobile including same

Abstract

The present invention relates to a battery pack characterized by including at least one battery module including a plurality of battery cells and a module case that houses the plurality of battery cells, a pack case that houses the battery module, a top cover that is housed inside the pack case and configured to cover an upper part of the battery module while being spaced apart from the pack case, and a lift-up prevention member that is configured to maintain a separation distance between the top cover and the pack case.

Description

[Technical Field]

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

[0002] This application claims priority based on Korean Patent Application No. 10-2023-0112297, filed on August 25, 2023, the entire contents of which are incorporated herein by reference in their entirety in the specification and drawings thereof. [Background technology]

[0003] Secondary batteries, which are highly adaptable to various product groups and have electrical properties such as high energy density, are widely used not only in portable devices but also in electric vehicles (EVs) and hybrid electric vehicles (HEVs), which are powered by electrical sources. In addition to the primary advantage of dramatically reducing the use of fossil fuels, these secondary batteries are attracting attention as a new energy source for improving environmental friendliness and energy efficiency, as they do not produce any by-products associated with energy use.

[0004] Currently widely used types of secondary batteries include lithium-ion batteries, lithium polymer batteries, nickel-cadmium batteries, nickel-metal hydride batteries, and nickel-zinc batteries. When a high output voltage is required, a battery module or a battery pack may be configured by connecting multiple battery cells in series. To increase the charge / discharge capacity, multiple battery cells may be connected in parallel. Therefore, the number of battery cells included in the battery module or pack may vary depending on the required output voltage or charge / discharge capacity.

[0005] However, because battery cells undergo chemical reactions during charging and discharging, their performance may deteriorate if they are used in an environment that is higher than the appropriate temperature, and if thermal control is not performed at the appropriate temperature, there is always the possibility of unexpected fire or explosion. Therefore, if a thermal event such as thermal runaway occurs inside a battery pack, high-temperature gases or flames emitted from the battery cells inside can spread to adjacent battery modules, causing a chain reaction of battery module explosions, which is extremely dangerous.

[0006] A battery module is constructed by housing battery cells in a module frame, and a battery pack houses these battery modules in a pack case. Conventionally, high-temperature gases, flames, etc. are discharged through vent holes provided in the upper part of the module frame and are discharged to the outside of the pack case through the space between the pack case and the battery modules. However, the shape of the pack case is deformed by the heat of the high-temperature gases, flames, etc., making it impossible to maintain the distance between the pack case and the battery modules, making it difficult to ensure a path for the high-temperature gases, flames, etc. to be discharged to the outside of the pack case.

[0007] Therefore, there is a need to develop a structure that can ensure a path for discharging the high-temperature gases and flames generated inside the battery module to the outside of the battery pack when thermal runaway occurs in the battery module, thereby preventing heat accumulation inside the battery pack.

[0008] In addition, it is necessary to develop a structure that can prevent gases and flames discharged outside the battery module from re-entering the battery module. Summary of the Invention [Problem to be solved by the invention]

[0009] Therefore, the problem to be solved by the present invention is to provide a battery pack that can effectively prevent or delay the propagation of thermal runaway between battery modules by smoothly discharging gases and flames generated inside the battery module to the outside of the battery pack when thermal runaway occurs in the battery module.

[0010] Another problem to be solved by the present invention is to provide a battery pack with improved safety and reliability by preventing gas or flames discharged outside the battery module from re-entering the battery module when thermal runaway occurs in the battery module.

[0011] Still another problem to be solved by the present invention is to provide a vehicle including such a battery pack.

[0012] However, the problems that the present invention aims to solve are not limited to the above-mentioned problems, and other problems not described can be clearly understood by those skilled in the art from the description of the invention described below. [Means for solving the problem]

[0013] In order to solve the above problem, the present invention provides a battery pack comprising: at least one battery module including a plurality of battery cells and a module case that houses the plurality of battery cells; a pack case that houses the battery module; a top cover that is housed inside the pack case and configured to be spaced apart from the pack case and cover the top of the battery module; and a lift-up prevention member that is configured to maintain the distance between the top cover and the pack case.

[0014] The pack case may include a box-shaped pack bottom frame with an open top and a pack lid that covers the open top of the pack bottom frame, and the anti-lifting member may be provided on the pack lid.

[0015] A vent passage may be formed in a space between the anti-lifting member, the pack lid, and the top cover, and the anti-lifting member may be configured to maintain the height of the vent passage.

[0016] At least a portion of the anti-lifting member may be configured to protrude from the pack lid toward the top cover and to contact an upper surface of the top cover.

[0017] The length by which the anti-lifting member protrudes from the pack lid may be configured to be equal to the distance between the pack lid and the top cover.

[0018] The anti-lifting member may include a protruding portion that protrudes from the pack lid, and a connecting portion that extends from the protruding portion and is configured to be connected to the pack lid.

[0019] The cross-sectional area of ​​the protrusion may be configured to be larger than the cross-sectional area of ​​the coupling portion.

[0020] The anti-lifting member may be made of a rigid body.

[0021] The anti-lifting member may be made of a material having fire resistance.

[0022] The battery pack according to an embodiment of the present invention may further include an insulating coating layer formed on an outer surface of the anti-lifting member.

[0023] A plurality of the anti-lifting members may be provided and may be arranged spaced apart from each other.

[0024] The anti-lifting member may be configured in an island shape.

[0025] At least one vent hole may be formed on the top surface of the module case through which vent gas discharged from the battery cell is discharged, and at least one cover hole may be formed on the top cover, the cover hole being positioned to correspond to the vent hole and configured to be opened by the vent gas.

[0026] The anti-lifting member may be fastened to the pack lid, and the fastening density of the anti-lifting member may be configured to vary depending on the position where the cover hole is formed.

[0027] The cover holes may be provided in plurality and arranged in a line along one direction, and the anti-lifting member may be provided between adjacent cover holes.

[0028] The anti-lifting member may be configured so that the area projected onto the top cover is smaller than the area of ​​the cover hole.

[0029] The anti-floating member may be bolted to the pack lid.

[0030] The anti-floating member may be welded to the pack lid.

[0031] The top cover may be made of a mica material.

[0032] The present invention also provides a motor vehicle including a battery pack according to the present invention. [Effects of the Invention]

[0033] According to one aspect of the present invention, when an abnormality occurs in a battery module, a path for high-temperature gas or flame generated in the battery module to be discharged to the outside of the battery pack can be secured, thereby effectively preventing or delaying the propagation of thermal runaway between battery modules and ensuring the safety and reliability of the battery pack.

[0034] Furthermore, according to another aspect of the present invention, when an abnormality occurs in the battery module, it is possible to prevent high-temperature gas, flames, etc. generated in the battery cells from re-entering the battery module.

[0035] Furthermore, according to still another aspect of the present invention, it is possible to prevent or delay events such as fires and explosions caused by thermal runaway in a device equipped with a battery pack.

[0036] In addition to the above, the present invention may have various other effects, but these will be described in each embodiment, or the description of effects that can be easily inferred by a person skilled in the art will be omitted.

[0037] The drawings attached to this specification illustrate preferred embodiments of the present invention and, together with the detailed description of the invention described below, serve to further understand the technical concept of the present invention. Therefore, the present invention should not be interpreted as being limited solely to the matters described in the drawings. [Brief explanation of the drawings]

[0038] [Figure 1] 1 is an overall perspective view of a battery pack according to an embodiment of the present invention; [Figure 2] 1 is an exploded perspective view of a battery module included in a battery pack according to an embodiment of the present invention. [Figure 3] 1 is an exploded perspective view of a battery pack according to an embodiment of the present invention; [Figure 4] 1A is a diagram showing a portion of the II' cross section of FIG. 1, illustrating the flow direction of vent gas and the like when a floating prevention member included in a battery pack according to one embodiment of the present invention is provided. FIG. [Figure 5] 1 is a perspective view of a lift-up prevention member included in a battery pack according to an embodiment of the present invention. FIG. [Figure 6] FIG. 10 is a diagram showing a comparative example in which the anti-lifting member included in the battery pack according to one embodiment of the present invention is not provided. [Figure 7] 10A and 10B are diagrams illustrating a battery pack according to another embodiment of the present invention, in which a lift-up prevention member is provided. [Figure 8] 1 is an assembled perspective view of a main part of a battery pack according to an embodiment of the present invention; [Figure 9] FIG. 9 is a cross-sectional view taken along line II-II′ of FIG. 8. [Figure 10] 10A and 10B are diagrams showing the arrangement of anti-lifting members included in a battery pack according to still another embodiment of the present invention. [Figure 11] 1 is a schematic perspective view of a vehicle including a battery pack according to an embodiment of the present invention. DETAILED DESCRIPTION OF THE INVENTION

[0039] Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings. Prior to this, the terms and phrases used in the 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 that is consistent with the technical idea of ​​the present invention, based on the principle that the inventor can appropriately define the concept of the term in order to best describe his / her invention.

[0040] Therefore, it should be understood that the embodiments described in this specification and the configurations shown in the drawings are merely the most preferred embodiments of the present invention and do not represent the entire technical idea of ​​the present invention, and that there may be various equivalents and modifications that can replace them at the time of this application.

[0041] The present invention includes various embodiments, and the following description will focus on differences and omit redundant explanations of substantially the same or similar configurations in the embodiments.

[0042] Meanwhile, in the present invention, terms indicating directions such as up, down, left, right, front, and back may be used, but these terms are used 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 or the position of the observer, etc.

[0043] For example, in an embodiment of the present invention, the X-axis direction shown in the drawings may refer to the front-to-back direction, the Y-axis direction may refer to the left-to-right direction perpendicular to the X-axis direction on a horizontal plane (XY plane), and the Z-axis direction may refer to the up-down direction (vertical direction) perpendicular to both the X-axis direction and the Y-axis direction.

[0044] Fig. 1 is an overall perspective view of a battery pack according to one embodiment of the present invention, Fig. 2 is an exploded perspective view of a battery module included in the battery pack according to one embodiment of the present invention, and Fig. 3 is an exploded perspective view of the battery pack according to one embodiment of the present invention. Also, Fig. 4 is a view showing a part of the II' cross section of Fig. 1, which shows the flow direction of vent gas and the like when a floating prevention member included in the battery pack according to one embodiment of the present invention is provided, and Fig. 5 is a perspective view of the floating prevention member included in the battery pack according to one embodiment of the present invention.

[0045] 1 to 3, a battery pack 10 according to one embodiment of the present invention may include a battery module 100, a pack case 200, a top cover 300, and a lift-up prevention member 400.

[0046] 1, a battery pack 10 according to the present invention may include a pack case 200. The pack case 200 forms the outer shell of the battery pack 10. The pack case 200 may have a predetermined length in each of the X-axis, Y-axis, and Z-axis directions and may have a generally rectangular parallelepiped shape as a whole. The pack case 200 may include a box-shaped pack bottom frame 210 with an open top, and a pack lid 220 that covers the open top of the pack bottom frame 210.

[0047] 2, a battery pack 10 according to the present invention can include at least one, and preferably a plurality of, battery modules 100. The battery modules 100 can be housed in the pack case 200 of FIG.

[0048] Each of the plurality of battery modules 100 may include a plurality of battery cells 110. At this time, the plurality of battery cells 110 included in the battery module 100 may be electrically connected to each other. That is, the battery pack 10 according to the present invention includes a plurality of battery modules 100, and the plurality of battery cells 110 included in the battery pack 10 may be divided and included among the plurality of battery modules 100.

[0049] The battery cell 110 may be configured as a pouch type. The cell case of such a pouch type battery cell 110 may be formed in a pouch shape in which an aluminum metal layer is sandwiched between polymer layers.

[0050] Although not shown, such a pouch-type battery cell 110 may include an electrode assembly, a cell case that houses the electrode assembly, and electrode leads that are connected to the electrode assembly and drawn out of the cell case to function as electrode terminals. The cell case may include a housing that houses the electrode assembly and a seal that seals the periphery of the housing.

[0051] At this time, the plurality of battery cells 110 may be arranged in parallel in the left-right direction (Y-axis direction) while standing upright in the up-down direction (Z-axis direction), as shown in Fig. 2. At this time, the seal portion of each battery cell 110 may face the front-rear direction (X-axis direction) and the up-down direction (Z-axis direction), and the storage portion may face the left-right direction (Y-axis direction).

[0052] It should be noted that the present invention is not limited to a specific type or shape of the battery cell 110, and various battery cells 110 known at the time of filing of the present invention may be adopted to configure the battery pack 10 of the present invention. In this embodiment, as shown in the drawings, a pouch-type secondary battery that has high energy density and is easy to stack is targeted, but it goes without saying that a cylindrical or prismatic secondary battery may also be used as the battery cell 110.

[0053] The battery module 100 may also include a module case 120. The module case 120 may be configured to form a space therein and to accommodate at least some of the plurality of battery cells 110 in the interior space. In particular, the module case 120 may be included in each battery module 100 to group the plurality of battery cells 110 into a plurality of battery modules 100 and serve as a boundary that physically separates the interior space of each battery module 100. The module case 120 may be made of a metal material having rigidity and heat resistance to physically and chemically protect the accommodated battery cells 110.

[0054] 2, the module case 120 may be configured as a U-shaped frame. When the module case 120 is configured as a U-shaped frame, it may be configured to cover both side surfaces and a bottom surface of the battery cell 110. The module case 120 may include left and right plates that cover both side surfaces of the battery cell 110, and a bottom plate that covers the bottom surface of the battery cell 110. The left, right and bottom plates may be configured as an integrated unit. In this case, the top and front and rear surfaces of the module case 120 may be open.

[0055] In this case, the battery module 100 may further include a top plate 130. When the module case 120 is configured as a U-shaped frame, the top plate 130 may be coupled to an open upper surface of the module case 120. In this case, the shape of the top plate 130 and the module case 120 coupled together may be a rectangular tube shape with open front and rear surfaces.

[0056] In addition, the module case 120 may be formed in various other shapes. For example, the module case 120 may include a box-shaped lower case having an open top end and an upper cover that closes the open top end of the lower case. In this case, the lower case may be configured with left and right plates that cover both sides of the battery cells 110, and front and rear plates that cover the front and rear of the battery cells 110, all integrated into one body.

[0057] Alternatively, the module case 120 may be configured as a monoframe. For example, the module case 120 may be formed in the shape of a rectangular tube having an upper surface, a lower surface, a left side surface, and a right side surface, and having an open front and rear surface.

[0058] Meanwhile, the battery module 100 may include end plates 140 provided on the open front and rear surfaces of the module case 120. The end plates 140 may be welded to the module case 120. Although not shown for convenience, the end plates 140 may be made of, for example, an insulating material on the inside and a metal material on the outside. The end plates 140 may also be partially provided with holes or slits to expose components that need to be exposed to the outside, such as the positive and negative terminals or connectors of the battery module 100.

[0059] Although not shown, the battery module 100 may also include a bus bar assembly and / or a module terminal electrically connected to the plurality of battery cells 110 housed therein.

[0060] Meanwhile, at least one vent hole 150 may be formed in the module case 120. Preferably, a plurality of vent holes 150 may be formed. The vent hole 150 may be configured to discharge vent gas generated in the battery cells 110 to the outside of the module case 120. The vent hole 150 may be formed on one side of the module case 120, allowing directional venting in one direction. For example, the vent hole 150 may be formed on the top surface of the module case 120. As shown in FIG. 2 , the vent hole 150 may be formed in the top plate 130. According to the embodiment of the present invention, the remaining portion of the module case 120 except for the vent hole 150 is sealed, and gas or flames may be discharged toward the vent hole 150 in a straight line.

[0061] 3, the pack case 200 may be configured to accommodate a plurality of battery modules 100. That is, the pack case 200 may provide an accommodation space in which a plurality of battery modules 100 can be accommodated. The pack case 200 may be made of or include a material that can ensure mechanical rigidity, such as a metal such as stainless steel (SUS) or a fiber-reinforced plastic, in order to safely protect the battery modules 100 accommodated therein.

[0062] The pack bottom frame 210 may include a base frame 211 and a side frame 212 .

[0063] The base frame 211 may be configured to mount a plurality of battery modules 100. The base frame 211 may form the lower surface of the pack case 200 and may be formed in a rectangular plate shape. The base frame 211 may also have a flat upper surface and may be configured to stably mount the module case 120.

[0064] The side frames 212 may extend upward from each side edge of the base frame 211. The side frames 212 may include a plurality of unit walls and may be provided to surround a plurality of battery modules 100. More specifically, the side frames 212 may include a right wall located at the end of the base frame 211 in the +Y direction, a front wall located at the end of the +X direction, a left wall located at the end of the base frame 211 in the -Y direction, and a rear wall located at the end of the -X direction, forming side surfaces of the pack case 200.

[0065] Meanwhile, the plurality of battery modules 100 may be arranged adjacent to each other in a plurality of rows in the front-rear direction and / or the left-right direction. For example, as shown in Fig. 3, the plurality of battery modules 100 may be arranged in two rows along the front-rear direction (X-axis direction) and in four rows along the left-right direction (Y-axis direction).

[0066] 3 , the pack bottom frame 210 may include a cross member 213. The cross member 213 may be configured to separate a plurality of battery modules 100. A plurality of cross members 213 may be provided. The cross member 213 may be provided on an upper portion of a base frame 211 and may be coupled to the base frame 211. The cross member 213 may be coupled to the base frame 211 by bolting or welding.

[0067] The pack lid 220 may be coupled to the upper portion of the side frame 212 to form the upper surface of the pack case 200. In this case, the pack lid 220 may be spaced apart from the upper end of the cross member 213 and the battery module 100 at a predetermined interval in the vertical direction (Z-axis direction).

[0068] The pack case 200 may also include a vent device 230. The vent device 230 may be provided on a side surface of the pack case 200, i.e., on the side frame 212. The vent device 230 may be configured to exhaust gas generated in the battery cells 110 housed therein to the outside of the pack case 200. Specifically, a gap may exist between the pack lid 220 and the cross member 213. Therefore, gas exhausted upward through the vent holes 150 of the battery module 100 may move to the gap between the pack lid 220 and the cross member 213. Such gas may be exhausted to the outside of the pack case 200 via the vent device 230.

[0069] Meanwhile, referring to FIGS. 2 and 3, the battery module 100 according to an embodiment of the present invention may further include a top cover 300.

[0070] The top cover 300 may be configured to cover an upper portion of the battery module 100. The top cover 300 may be provided by being adhered to the top plate 130. The top cover 300 may be attached to the top plate 130 by an adhesive member. The adhesive member may include an adhesive agent, an adhesive tape, etc. The top cover 300 may be accommodated inside the pack case 200 and provided to be spaced apart from the pack lid 220 in the vertical direction (Z-axis direction).

[0071] The top cover 300 may be made of a material with excellent heat resistance and / or fire resistance, such as a pad combining mica, a fire-resistant barrier (FRB), and silicone, etc. The FRB may include an inorganic material that is easily deformed, and may be made of a material with very high flame retardancy and flame resistance.

[0072] Therefore, according to the embodiment of the present invention, even when high temperature heat is generated, the top cover 300 does not shrink and can maintain its shape stability, thereby stably blocking high temperature gas, flame, etc. generated in the battery cell 110. Furthermore, even if a thermal event occurs inside the battery module 100, the provision of the top cover 300 can prevent the heat of high temperature gas, flame, etc. from being transmitted to the outside.

[0073] A cover hole 310 may be formed in the top cover 300. A plurality of the cover holes 310 may be provided and may be arranged to correspond to the vent holes 150. That is, the cover holes 310 may be provided at the positions where the vent holes 150 are formed, and may have the same shape and size as the vent holes 150. Such cover holes 310 may be provided to cover the vent holes 150.

[0074] The cover holes 310 may be configured to be opened by the pressure of vent gas or flames discharged from the battery cells 110. Specifically, when gas is discharged from the vent holes 150 corresponding to the cover holes 310, only the cover holes 310 provided on the upper portions of the vented battery cells 110 may be configured to break from the top cover 300. For this purpose, notched grooves may be formed along the shape of the cover holes 310. Alternatively, grooves or notches may be formed in parts of the cover holes 310 and may be indicated by dashed or solid lines.

[0075] As a result, in a normal state, the top cover 300 covers the vent holes 150, thereby protecting the battery cells 110 in the module case 120. Furthermore, in the event of a thermal event in which vent gas or flames are generated in some of the battery cells 110, the cover holes 310 are separated from the top cover 300, so that the vent gas or flames that are discharged directly through the vent holes 150 are not obstructed and can be smoothly discharged to the outside of the battery module 100. At the same time, the remaining cover holes 310 remain connected to the top cover 300, so that the discharged gases can be prevented from re-entering the battery module 100.

[0076] 3 to 5, the battery pack 10 of the present invention includes a lift-up prevention member 400. The lift-up prevention member 400 may be configured to maintain a separation distance between the top cover 300 and the pack case 200.

[0077] As described above, the top cover 300 and the pack lid 220 are spaced apart by a predetermined distance, and vent gas, flames, and the like can move through the space between them. That is, a vent passage S can be formed in the space between the anti-lifting member 400, the pack lid 220, and the top cover 300. In this case, the anti-lifting member 400 can be provided on the pack lid 220 and configured to maintain a constant height d of the vent passage S. Here, the height d of the vent passage S refers to the length in the vertical direction (Z-axis direction), and can refer to the vertical distance from the upper surface of the top cover 300 to the lower surface of the pack lid 220.

[0078] High heat from vent gases, flames, or the like may melt the adhesive material provided between the top plate 130 and the top cover 300, reducing the adhesive strength. In this case, if a portion of the top cover 300 remains without being separated from the top plate 130 with the adhesive strength of the adhesive material reduced, the top cover 300 may separate from the top plate 130, reducing the distance d between the pack lid 220 and the top cover 300. This may prevent the vent flow path S from being secured, preventing the vent gases, flames, and the like from being discharged to the outside of the battery pack 10, potentially resulting in thermal runaway.

[0079] However, according to the above embodiment of the present invention, the anti-lifting member 400 applies pressure to the top cover 300, thereby preventing the top cover 300 from being separated from the module case 120. This ensures the height d of the vent flow path S, allowing vent gas, flames, and the like to move smoothly through the vent flow path S, as shown by the arrows in FIG.

[0080] Furthermore, according to the above-described embodiment of the present invention, it is possible to prevent vent gas, flames, and the like discharged to the outside of the battery module 100 from entering through the raised interface (a state in which the interface is raised) between the top cover 300 and the top plate 130 and re-flowing into the battery module 100. This makes it possible to suppress or prevent thermal runaway of the battery cells 110 inside the battery module 100. As a result, it is possible to ensure the safety and reliability of the battery pack 10.

[0081] The anti-lifting member 400 may be made of a rigid body. Here, the term "rigid body" is used in contrast to an elastic body, and the anti-lifting member 400 may be made of, for example, a metal such as SUS or a material such as a fiber-reinforced plastic. This increases the mechanical rigidity of the anti-lifting member 400, and since elastic deformation hardly occurs, the gap d between the pack lid 220 and the top cover 300 can be maintained constant even when an external impact is applied.

[0082] Furthermore, the anti-lifting member 400 may be made of a fire-resistant material. For example, the anti-lifting member 400 may be made of a material such as flame-retardant plastic or mica. According to the above-described embodiment of the present invention, the anti-lifting member 400 can be prevented from melting or disappearing due to high heat such as a flame. Therefore, even in a situation where a flame occurs, the anti-lifting member 400 can maintain the distance d between the pack lid 220 and the top cover 300.

[0083] The structure of the anti-lifting member 400 will be described in detail with reference to Figures 4 and 5. At least a portion of the anti-lifting member 400 can be configured to protrude from the pack lid 220 toward the top cover 300 and contact the upper surface of the top cover 300.

[0084] In this case, the anti-lifting member 400 may be formed in a bolt shape. Specifically, the anti-lifting member 400 may include a protruding portion 410 that protrudes from the pack lid 220, and a coupling portion 420 that extends from the protruding portion 410 and is configured to be coupled to the pack lid 220. In this case, it is preferable that the protruding portion 410, which corresponds to the head of the bolt, has a flat head rather than a round head to ensure a large contact area with the top cover 300.

[0085] 4 and 5, the length by which the anti-lifting member 400 protrudes from the pack lid 220, i.e., the vertical height L of the protrusion 410, can be configured to be equal to the distance d between the pack lid 220 and the top cover 300. As a result, the lower surface of the protrusion 410 can be configured to contact the upper surface of the top cover 300, and at the same time, the upper surface of the protrusion 410 can be configured to contact the lower surface of the pack lid 220. According to the embodiment of the present invention, when the top cover 300 separates from the top plate 130 and attempts to lift up, the lower surface of the protrusion 410 presses against the upper surface of the top cover 300, thereby preventing the top cover 300 from lifting up.

[0086] Furthermore, the cross-sectional area of ​​the protrusion 410 in the direction perpendicular to the Z axis may be configured to be larger than the cross-sectional area of ​​the coupling portion 420. This allows the protrusion 410 to simultaneously and stably fix the pack lid 220 and the top cover 300, and further prevents deformation due to high heat or the like.

[0087] On the other hand, FIG. 6 shows, as a comparative example, a case where the anti-floating member included in the battery pack according to one embodiment of the present invention is not provided.

[0088] 6 , which is a comparative example, if the anti-lifting member 400 is not provided, when thermal runaway occurs in the battery module 100, the shape of the pack lid 220 may be deformed by the pressure of gas discharged from the battery cells 110 and / or the high heat of dust, flames, etc. For example, a portion of the pack lid 220 located above the vent hole 150 and cover hole 310 through which gas, flames, etc. are discharged may bulge upward (in the direction of the thick arrow in FIG. 6 ), while the adjacent portion may be recessed downward (in the direction of the thin arrow in FIG. 6 ). As a result, the gap between the pack lid 220 and the top cover 300 is reduced in the recessed downward portion of the pack lid 220, and a vent path is not secured, which may prevent the vent gas, flames, etc. from moving to the vent device 230.

[0089] However, according to one embodiment of the present invention, the coupling portion 420 of the anti-lifting member 400 is firmly coupled to the pack lid 220, thereby preventing the pack lid 220 from bending or deforming due to pressure from vent gas or the like and / or heat. Specifically, as shown in Fig. 5, a thread may be formed on the coupling portion 420, and correspondingly, a groove having the same shape as the thread is provided on the pack lid 220, allowing the coupling portion 420 to be coupled. That is, the pack lid 220 is tapped, and the bolt-shaped anti-lifting member 400 is fastened to the tapped portion.

[0090] Therefore, according to the embodiment of the present invention, the gap d between the pack lid 220 and the top cover 300 can be maintained, thereby ensuring the vent path S. This allows vent gas, flames, and the like to be smoothly discharged to the outside of the battery pack 10, thereby suppressing or preventing thermal runaway between the battery modules 100. As a result, the safety and reliability of the battery pack 10 can be ensured.

[0091] FIG. 7 is a diagram showing a battery pack according to another embodiment of the present invention that is provided with a lift-up prevention member.

[0092] Meanwhile, referring to Fig. 7, a battery pack 10 according to another embodiment of the present invention may include a lift-up prevention member 400 having an insulating coating layer 500 formed thereon. The insulating coating layer 500 may be formed on an outer surface of the lift-up prevention member 400. The insulating coating layer 500 may be configured to not only electrically insulate the lift-up prevention member 400 but also prevent heat conduction. To this end, the insulating coating layer 500 may be made of a material such as polyurethane or silicone.

[0093] 7, the insulating coating layer 500 may be formed on a portion of the anti-lifting member 400 exposed from the pack lid 220. That is, the insulating coating layer 500 may be formed on the remaining surfaces of the protrusion 410 excluding the surface that contacts the pack lid 220. For example, the insulating coating layer 500 may be provided to surround the lower surface and side surfaces of the protrusion 410. According to the above embodiment of the present invention, the insulating coating layer 500 reliably maintains an insulating and / or heat conduction preventing effect on the portion of the anti-lifting member 400 that is exposed to vent gas, flames, etc.

[0094] The insulating coating layer 500 may be a coating layer formed by directly foaming on the outer surface of the anti-lifting member 400 after the anti-lifting member 400 is assembled to the pack lid 220. According to the embodiment of the present invention, the outer surface of the anti-lifting member 400 can be easily covered compared to the case where a separately prepared sheet-shaped insulating member is attached. In addition, since the process of separately manufacturing an insulating member according to the dimensions of the outer surface of the anti-lifting member 400 is omitted, the cost and time required for manufacturing the battery module can be reduced.

[0095] Fig. 8 is an assembled perspective view of the main parts of a battery pack according to one embodiment of the present invention, and Fig. 9 is a cross-sectional view taken along line II-II' in Fig. 8. Also, Fig. 10 is a view showing the arrangement of anti-lifting members in a battery pack according to still another embodiment of the present invention.

[0096] 8 to 10, a plurality of anti-floating members 400 may be provided and spaced apart from one another. The anti-floating members 400 may be configured in an island shape. According to the embodiment of the present invention, the anti-floating members 400 are formed in an island shape rather than a long beam shape, so that the arrangement position of the anti-floating members 400 can be freely set. This increases design freedom and improves productivity. The anti-floating members 400 may be isotropic in the XY plane. When connecting the anti-floating members 400 to the pack lid 220, the orientation of the anti-floating members 400 does not need to be considered, improving assembly efficiency.

[0097] The anti-lifting member 400 may be welded to the pack lid 220. Alternatively, the anti-lifting member 400 may be bolted to the pack lid 220. According to the embodiment of the present invention, even if the anti-lifting member 400 is incorrectly assembled to the pack lid 220, it can be easily removed and corrected, thereby improving the ease of assembly during the manufacture of the battery pack 10.

[0098] In this case, the density at which the anti-lifting members 400 are fastened to the pack lid 220 (fastening density) may be configured to vary depending on the positions at which the cover holes 310 are formed. Here, the fastening density may refer to the number of anti-lifting members 400 per unit area of ​​the pack lid 220 or the area occupied by the anti-lifting members 400. The area and number of the anti-lifting members 400 may be freely adjusted depending on the area and number of the cover holes 310. For example, as shown in the embodiment of FIG. 10 , after identifying in advance through experiments the areas at which the top cover 300 is likely to lift, the battery pack 10 may be manufactured so that the anti-lifting members 400 are more densely arranged in those areas. According to the above embodiment of the present invention, design freedom can be increased, productivity can be further improved, and an event can be flexibly handled without changing the design of other parts of the battery pack 10.

[0099] Specifically, the anti-lifting members 400 may be disposed between adjacent cover holes 310 among the plurality of cover holes 310. That is, the anti-lifting members 400 may be disposed in portions of the top cover 300 adjacent to the cover holes 310. For example, as shown in FIGS. 8 and 9, the plurality of cover holes 310 may be disposed in a line in the front-rear direction (X-axis direction), and the anti-lifting members 400 may be disposed in groups of three along the left-right direction (Y-axis direction) between adjacent cover holes 310 among the cover holes 310 disposed in a line. Furthermore, the anti-lifting members 400 may also be disposed at both ends of the top cover 300 in the front-rear direction (X-axis direction).

[0100] When vent gas, flames, or the like are discharged from vent hole 150, the heat of the vent gas, flames, or the like is likely to cause a portion of top cover 300 adjacent to separated cover hole 310 to lift up and separate from top plate 130. Therefore, by providing anti-lift member 400 in a portion adjacent to cover hole 310 as in the above embodiment of the present invention, it is possible to effectively prevent the portion of top cover 300 adjacent to cover hole 310 from lifting up.

[0101] 9, the area of ​​the anti-lifting member 400 projected onto the top cover 300 may be configured to be smaller than the area of ​​the cover hole 310. More specifically, the cross-sectional area of ​​the protrusion 410 of the anti-lifting member 400 may be configured to be smaller than the area of ​​the space between adjacent cover holes 310. This prevents the anti-lifting member 400 from blocking the vent hole 150 or the cover hole 310, and does not prevent vent gas or flames from being discharged through the vent hole 150 or the cover hole 310.

[0102] As a result, by providing the anti-lifting members 400 in a localized region of the top cover 300, it becomes possible for vent gas, flames, and the like to move through the anti-lifting members 400, as shown by the arrows in Fig. 9. That is, according to the embodiment of the present invention, the vent flow path S is more secure, and the propagation of thermal runaway between the battery modules 100 can be effectively prevented or delayed.

[0103] FIG. 11 is a schematic perspective view of an automobile including a battery pack according to one embodiment of the present invention.

[0104] 11 , an automobile 20 according to an embodiment of the present invention may include one or more battery packs 10 or battery modules 100 according to an embodiment of the present invention. The automobile 20 according to the present invention may be, for example, an electric vehicle, a hybrid vehicle, or a plug-in hybrid vehicle. The automobile 20 includes four-wheeled vehicles and two-wheeled vehicles. The automobile 20 operates by receiving a supply of power from the battery pack 10 or battery module 100 according to an embodiment of the present invention.

[0105] Although the present invention has been described above using limited embodiments and drawings, the present invention is not limited thereto, and it goes without saying that various modifications and variations can be made by a person having ordinary knowledge in the technical field to which the present invention pertains within the technical spirit of the present invention and the equivalent scope of the appended claims. [Explanation of symbols]

[0106] 10 Battery pack 20. Automobiles 100 Battery Module 110 battery cells 120 module case 130 Top Plate 140 End Plate 150 vent hole 200 pack case 210 Pack Bottom Frame 211 base frame 212 Side Frame 213 Cross member 220 Pack Lid 230 Vent Device 300 top cover 310 Cover hole 400 Anti-floating material 410 Protrusion 420 Joint 500 insulating coating layers

Claims

1. at least one battery module including a plurality of battery cells and a module case that houses the plurality of battery cells; a pack case that houses the battery module; a top cover that is accommodated inside the pack case and is spaced apart from the pack case to cover an upper portion of the battery module; a lift-up prevention member configured to maintain a separation distance between the top cover and the pack case; Including the battery pack.

2. The pack case is A box-shaped pack bottom frame with an open top, a pack lid for covering the open top surface of the pack bottom frame, The battery pack according to claim 1 , wherein the anti-lifting member is provided on the pack lid.

3. a vent passage is formed in a space between the anti-lifting member, the pack lid, and the top cover; The battery pack according to claim 2 , wherein the anti-lifting member is configured to maintain the height of the vent flow path.

4. The battery pack according to claim 2 , wherein at least a portion of the anti-lifting member is configured to protrude from the pack lid toward the top cover and to contact an upper surface of the top cover.

5. 5. The battery pack according to claim 4, wherein the length by which the anti-lifting member protrudes from the pack lid is equal to the distance between the pack lid and the top cover.

6. The anti-floating member is a protrusion provided to protrude from the pack lid; 3. The battery pack of claim 2, further comprising: a coupling portion extending from the protrusion and configured to be coupled to the pack lid.

7. The battery pack according to claim 6 , wherein a cross-sectional area of ​​the protrusion is larger than a cross-sectional area of ​​the coupling portion.

8. The battery pack according to claim 1 , wherein the anti-lifting member is made of a rigid body.

9. The battery pack according to claim 1 , wherein the anti-lifting member is made of a fire-resistant material.

10. The battery pack according to claim 1 , further comprising an insulating coating layer formed on an outer surface of the anti-lifting member.

11. The battery pack according to claim 1 , wherein a plurality of the anti-lifting members are provided and are spaced apart from each other.

12. The battery pack according to claim 11 , wherein the anti-lifting member is configured in an island shape.

13. At least one vent hole is formed in an upper surface of the module case through which vent gas discharged from the battery cell is discharged, The battery pack according to claim 2 , wherein the top cover is formed with at least one cover hole disposed to correspond to the vent hole and configured to be opened by the vent gas.

14. the anti-lifting member is fastened to the pack lid, The battery pack according to claim 13 , wherein the fastening density of the anti-lifting member is configured to vary depending on the position where the cover hole is formed.

15. The cover holes are provided in plurality and are arranged in a line along one direction, The battery pack according to claim 14 , wherein the anti-lifting member is provided between adjacent cover holes.

16. The battery pack according to claim 15 , wherein an area of ​​the anti-lifting member projected onto the top cover is smaller than an area of ​​the cover hole.

17. The battery pack according to claim 14 , wherein the anti-lifting member is connected to the pack lid by bolts.

18. The battery pack according to claim 14 , wherein the anti-lifting member is welded to the pack lid.

19. The battery pack of claim 13 , wherein the top cover is constructed from a mica material.

20. A motor vehicle comprising a battery pack according to any one of claims 1 to 19.

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