Battery module, battery pack including same, and automobile

Abstract

The present invention relates to a battery module including a cell stack including a plurality of battery cells, a module case configured to house the cell stack, and a top cover coupled to an upper portion of the module case, wherein at least a portion of the top cover is configured to be detached from the module case by vent gas or flame discharged from the battery cells.

Description

[Technical Field]

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

[0002] This application claims priority based on Korean Patent Application No. 10-2023-0090699, filed on July 12, 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 have high applicability across a range of products and electrical properties such as high energy density, are widely used not only in portable devices but also in electric vehicles (EVs) and hybrid electric vehicles (HEVs) that are powered by electrical sources. These secondary batteries not only have the temporary advantage of dramatically reducing the use of fossil fuels, but also have the advantage of producing no by-products associated with energy use, and are therefore attracting attention as a new energy source that is environmentally friendly and improves energy efficiency.

[0004] Currently widely used types of secondary batteries include lithium-ion batteries, lithium polymer batteries, nickel-cadmium batteries, nickel-metal hydride batteries, and nickel-zinc batteries. 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, a battery module or a battery pack may be configured by connecting multiple battery cells in parallel. Therefore, the number of battery cells included in the battery module or battery pack may be varied 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 environments higher than the appropriate temperature. Furthermore, if thermal control is not performed to maintain the appropriate temperature, there is a risk of unexpected fire or explosion. Furthermore, battery modules house these battery cells together inside a module housing. Therefore, if a thermal event occurs in one battery cell, the emitted high-temperature gas and flames may spread to adjacent battery cells, potentially causing a chain reaction of battery cell explosions, which is extremely dangerous.

[0006] Therefore, it is necessary to work on a mechanism that can prevent heat from accumulating inside the battery module by discharging high-temperature gases and flames generated inside the battery module to the outside when thermal runaway occurs in the battery module, and prevent the discharged gases and flames from flowing back into the battery module. Summary of the Invention [Problem to be solved by the invention]

[0007] Therefore, an object of the present invention is to provide a battery module that can effectively prevent or delay the propagation of thermal runaway between cells by smoothly discharging gases and flames generated inside the battery module to the outside of the battery module when thermal runaway occurs in the battery module.

[0008] Another problem to be solved by the present invention is to provide a battery module with improved safety and reliability by preventing gas or flames discharged outside the battery module from flowing back into the battery module when thermal runaway occurs in the battery module.

[0009] However, the technical problems that the present invention aims to solve are not limited to the above-mentioned problems, and other problems not mentioned will be clearly understood by those skilled in the art from the description of the invention given below. [Means for solving the problem]

[0010] In order to solve the above problems, the present invention provides a battery module including a cell stack including a plurality of battery cells, a module case configured to house the cell stack, and a top cover coupled to an upper portion of the module case, wherein at least a portion of the top cover is configured to be detached from the module case by vent gas or flame discharged from the battery cells.

[0011] The module case may include a top plate that forms an upper surface of the module case and has at least one first vent hole formed therein through which vent gas discharged from the battery cell is expelled, and the top cover may be coupled to the top plate.

[0012] The top cover may be adhered to the top plate.

[0013] The top cover may include at least one second vent hole provided to cover the first vent hole and configured to be detachable from the top plate by pressure of vent gas discharged from the battery cell.

[0014] The top cover may include a plurality of top cover regions in which some of the second vent holes are formed, and the plurality of top cover regions may be arranged so as to be separable from each other.

[0015] The top cover may include score lines disposed between the plurality of top cover regions and configured to allow each of the plurality of top cover regions to be torn.

[0016] When the battery cell is vented, only the top cover region disposed above the vented battery cell among the plurality of top cover regions may be detached from the top plate.

[0017] The remainder of the plurality of top cover regions may be arranged to remain coupled to the top plate.

[0018] The second vent holes may be provided in plural, and the plural second vent holes may form at least one vent hole array arranged in a line along the longitudinal direction of the battery cell.

[0019] The plurality of battery cells may be arranged in a stacked manner in one direction, and one vent hole array may be arranged to correspond to two or more of the battery cells.

[0020] The vent hole array may be provided in a plurality and arranged along the one direction.

[0021] At least one of the vent hole arrays may be formed in one of the top cover regions.

[0022] The present invention also provides a battery pack including the battery module according to the present invention.

[0023] The present invention also provides a vehicle comprising a battery pack according to the present invention. [Effects of the Invention]

[0024] According to one aspect of the present invention, when an abnormal condition occurs in a battery cell, high-temperature gases and flames generated in the battery cell can be smoothly discharged to the outside of the battery module, thereby effectively preventing or delaying the propagation of thermal runaway between cells.

[0025] In addition, according to another aspect of the present invention, when an abnormal condition occurs in a battery cell, high-temperature gas or flames generated in the battery cell can be prevented from flowing back into the battery module, thereby ensuring the safety and reliability of the battery module.

[0026] Furthermore, according to yet another aspect of the present invention, it is possible to prevent or delay events, such as fires and explosions, caused by thermal runaway phenomena in battery packs including multiple battery modules or in devices to which they are attached.

[0027] In addition to these, the present invention can have various other effects, which will be explained in the sections for each embodiment, and explanations of effects that can be easily inferred by those skilled in the art will be omitted.

[0028] The drawings attached to this specification illustrate preferred embodiments of the present invention and serve to further understand the technical concepts of the present invention as well as the content of the invention, and therefore the present invention should not be interpreted as being limited to only the matters depicted in the drawings. [Brief explanation of the drawings]

[0029] [Figure 1] 1 is an overall perspective view of a battery module according to an embodiment of the present invention; [Figure 2] 1 is an exploded perspective view of a battery module according to an embodiment of the present invention; [Figure 3] 1 is a plan view of a battery module according to an embodiment of the present invention; [Figure 4] 1 is a cross-sectional perspective view of a battery module according to an embodiment of the present invention; [Figure 5] 10 is a view illustrating a top cover from which a second vent hole is removed when thermal runaway occurs in a battery module according to an embodiment of the present invention. FIG. [Figure 6]10A and 10B are views illustrating a top cover that is partially removed when thermal runaway occurs in a battery module according to an embodiment of the present invention. [Figure 7] FIG. 2 is a perspective view of a top cover according to an embodiment of the present invention. [Figure 8] FIG. 10 is a plan view of a battery module according to another embodiment of the present invention. [Figure 9] 10A and 10B are views illustrating a top cover that is partially removed when thermal runaway occurs in a battery module according to another embodiment of the present invention; [Figure 10] 1 is a schematic perspective view of a battery pack including a battery module according to an 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

[0030] Hereinafter, a preferred embodiment of the present invention will be described in detail with reference to the accompanying drawings. Prior to this, the terms and words used in the specification and claims should not be construed as being limited to their ordinary or dictionary meanings, but should be construed as having meanings and concepts corresponding to the technical ideas of the present invention, in accordance with the principle that the inventor can appropriately define the concepts of terms himself in order to best describe the invention.

[0031] Therefore, it should be understood that the embodiments described in this specification and the configurations shown in the drawings are merely preferred embodiments of the present invention and do not represent the entire technical idea of ​​the present invention, and that there may be various equivalent and modified embodiments that can be substituted for them at the time of this application.

[0032] The present invention includes various embodiments, and the following description will be focused on the differences between the embodiments, omitting redundant explanations of substantially identical or similar configurations.

[0033] Meanwhile, although directional terms such as up, down, left, right, front, and rear are used in this specification, it will be obvious to those skilled in the art of the present invention that these terms are used merely for ease of explanation and may differ depending on the position of the object in question, the position of the observer, etc.

[0034] For example, in an embodiment of the present invention, the illustrated X-axis direction may refer to the left-right direction, the Y-axis direction may refer to the front-back direction that is 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) that is perpendicular to both the X-axis direction and the Y-axis direction.

[0035] Fig. 1 is an overall perspective view of a battery module according to an embodiment of the present invention, Fig. 2 is an exploded perspective view of the battery module according to an embodiment of the present invention, and Fig. 3 is a plan view of the battery module according to an embodiment of the present invention.

[0036] 1 to 3, a battery module 10 according to an embodiment of the present invention may include a cell stack 100, a module case 200, and a top cover 300.

[0037] The cell stack 100 may include a battery cell 110. The battery cell 110 may be provided in multiple numbers.

[0038] The plurality of battery cells 110 may be, for example, pouch-type secondary batteries. Each of the plurality of battery cells 110 may be provided with an electrode lead 112. Specifically, the plurality of battery cells 110 may include an electrode assembly, a cell case 111 that houses the electrode assembly, and an electrode lead 112 that is connected to the electrode assembly and extends to the outside of the cell case 111 to function as an electrode terminal. The cell case 111 may house the electrode assembly in a housing portion, and the edge portion around the housing portion may be heat-sealed to form a sealing portion.

[0039] The electrode leads 112 may be provided in pairs, and the pair of electrode leads 112 may be drawn out from both ends of the battery cell 110, i.e., in the longitudinal direction (±Y direction). In this case, the pair of electrode leads 112 may be a positive electrode lead and a negative electrode lead. If necessary, the battery cell 110 may have a configuration in which the two electrode leads 112 are located only at one end in the Y-axis direction, for example, at the end in the +Y-axis direction.

[0040] 2, the battery cells 110 may be arranged so as to stand upright in the vertical direction (Z-axis direction) and be aligned in the left-right direction (X-axis direction). In this case, the sealing portion of each battery cell 110 may face the front-rear direction (Y-axis direction) and the up-down direction (Z-axis direction), and the storage portion may face the left-right direction (X-axis direction).

[0041] The present invention is not limited in any way by the specific type or form of such battery cells 110, and a wide variety of battery cells 110 known at the time of filing of the present invention can be used to configure the cell stack 100 of the present invention. In this embodiment, as shown in the drawing, a pouch-type secondary battery that has high energy density and is easy to stack is targeted, but it goes without saying that cylindrical or prismatic secondary batteries can also be used as the battery cells 110.

[0042] The cell stack 100 may further include a blocking member 120. The blocking member 120 may be disposed between the battery cells 110. In particular, a plurality of blocking members 120 may be included in one cell stack 100. The blocking member 120 may be provided in a form in which it is disposed for at least one battery cell 110. In the present embodiment, the blocking member 120 may be disposed for every two battery cells 110. According to this embodiment of the present invention, the battery cells 110 are partitioned or separated, so that gas, flame, etc. can be prevented from propagating beyond the blocking member 120 and other adjacent blocking members 120.

[0043] The blocking member 120 may be made of a material having excellent heat resistance and / or fire resistance, such as silicon or aerogel. According to the embodiment of the present invention, the blocking member 120 can contribute to the structural rigidity of the battery cell 110 by compressing the battery cell 110 when swelling occurs in the battery cell 110.

[0044] 1 and 2, the module case 200 may be configured to accommodate the cell stack 100. Specifically, the module case 200 may be formed with an internal space, and may be configured to accommodate the cell stack 100 in the internal space.

[0045] Meanwhile, referring to FIG. 2 , the module case 200 may include a case body 210. For example, the case body 210 may be configured as a U-frame. When configured as a U-frame, the case body 210 may be configured to cover both sides and a bottom surface of the cell stack 100. The case body 210 may include a left plate and a right plate covering both sides of the cell stack 100, and a bottom plate covering the bottom surface of the cell stack 100. The left plate, the right plate, and the bottom plate may be configured as an integrated unit. In this case, the top surface, the front surface, and the rear surface of the case body 210 may be open. The case body 210 may be made of a metal material having rigidity and heat resistance to physically and chemically protect the housed battery cells 110.

[0046] The modular case 200 may further include a top plate 220. The top plate 220 may be arranged to form an upper surface of the modular case 200. When the case body 210 is arranged as a U-frame, the top plate 220 may be coupled to an open top surface of the case body 210. The top plate 220 may be coupled to the case body 210 by welding. In this case, the shape of the top plate 220 and the case body 210 combined may be a rectangular tube shape with open front and rear sides.

[0047] The case body 210 may be configured to allow the battery cell 110 to be inserted into the case body 210 in one direction. For example, the battery cell 110 may be inserted into the case body 210 in the front-rear direction (Y-axis direction). That is, the case body 210 may be configured to allow the battery cell 110 to be inserted into the case body 210 in a sliding manner.

[0048] Meanwhile, the module case 200 may include end plates 230 disposed on the open front and rear sides of the case body 210. The end plates 230 may be welded to the case body 210. Meanwhile, although not shown for ease of illustration, the end plates 230 may be made, for example, of an insulating material on the inside and a metal material on the outside. Also, the end plates 230 may have holes or slits partially formed thereon to expose components that need to be exposed to the outside, such as the positive and negative terminals or connectors of the battery module 10.

[0049] In addition, the module case 200 may be formed in a variety of shapes. For example, the module case 200 may include a box-shaped lower case having an open upper end and an upper cover that closes the open upper end of the lower case. In this case, the lower case may be provided with a left panel and a right panel that cover both sides of the cell stack 100, and a front panel and a rear panel that cover the front and rear of the cell stack 100, all of which are integrated into one piece.

[0050] Alternatively, the module case 200 may be provided as a monoframe. For example, the case body 210 may be configured as a rectangular tube having an upper side, a lower side, a left side, and a right side, and an open front and rear. The module case 200 including such a monoframe allows the cell stack 100 and the bus bar frame assembly 400 to be assembled and inserted into the monoframe by an interference fit, and the battery module 10 may be assembled by connecting end plates 230 to both open portions of the monoframe. Due to the interference fit, there may be little gaps between the lower surface and top plate 220 of the case body 210 and the battery cells 110, and there may also be little gaps between both side surfaces of the case body 210 and both sides of the battery cells 110.

[0051] Meanwhile, a first vent hole H1 may be formed in the top plate 220. The first vent hole H1 may be configured to exhaust vent gas generated in the battery cell 110 to the outside of the module case 200. The first vent hole H1 may be formed in the module case 200, and may perform directional venting in one direction.

[0052] 3, a first vent hole H1 may be formed in the top plate 220, and directional venting of the battery module 10 may be performed upward through the first vent hole H1. Specifically, a plurality of first vent holes H1 may be provided, and may be spaced apart from one another in the horizontal direction (X-axis and Y-axis directions).

[0053] According to the above-described embodiment of the present invention, in a situation where thermal runaway occurs in any one of the battery cells 110 and gas or the like is generated, directional venting of the gas or the like can be performed quickly in a specific direction from both sides of the module case 200.

[0054] In this way, the first vent hole H1 provided in the top plate 220 is arranged so that when thermal runaway occurs in the battery module 10, gas and flame generated inside the battery module 10 can be discharged to the outside of the battery module 10. The remaining part of the module case 200 excluding the first vent hole H1 is sealed, and the gas and flame can be discharged in a straight line toward the first vent hole H1.

[0055] Meanwhile, referring to Fig. 2, the battery module 10 of the present invention may further include a bus bar frame assembly 400. The bus bar frame assembly 400 may be disposed inside the module case 200 and configured to cover at least one side of the cell stack 100. In this embodiment, as shown in Fig. 2, the bus bar frame assembly 400 may be coupled to the front and rear of the cell stack 100.

[0056] The bus bar frame assembly 400 may include a bus bar frame 410 and a plurality of bus bars 420. The bus bar frame 410 may be provided so as to be coupled to the front and rear of the cell stack 100. The bus bar frame 410 may have slits that allow the electrode leads 112 of the battery cells 110 to be drawn out in the +Y-axis or -Y-axis direction. The bus bar frame 410 may be formed of an electrically insulating material, such as a plastic material, and may be configured to allow the bus bars 420 to be attached to its outer surface.

[0057] In addition, the bus bar frame 410 can be connected to the front or rear of the cell stack 100 in a manner that allows for a tight fit.

[0058] Meanwhile, the bus bars 420 are means for connecting the battery cells 110 in series and / or parallel, and may be made of a metal material such as copper, aluminum, or nickel, and may be provided in a rod shape. The electrode leads 112 of the battery cells 110 pass through slits in the bus bar frame 410 and are pulled out to the outside of the bus bar frame 410, and the pulled-out portions may be attached to the surfaces of the bus bars 420 by welding or other methods. By welding the electrode leads 112 of the battery cells 110 and the bus bars 420 to the front and rear of the cell stack 100 according to a predetermined pattern, the battery cells 110 can be connected in series and / or parallel.

[0059] In this embodiment, referring to FIG. 2, the module case 200 is a component having an internal space to accommodate the cell stack 100 and the bus bar frame assembly 400 and to protect the cell stack 100 from the outside.

[0060] Meanwhile, the battery module 10 according to an embodiment of the present invention may further include a top cover 300. The top cover 300 according to an embodiment of the present invention will be described in more detail with further reference to FIGS.

[0061] FIG. 4 is a cross-sectional perspective view of a battery module according to one embodiment of the present invention, FIG. 5 is a diagram illustrating a top cover from which a second vent hole is removed when thermal runaway occurs in a battery module according to one embodiment of the present invention, and FIG. 6 is a diagram illustrating a top cover from which only a portion is removed when thermal runaway occurs in a battery module according to one embodiment of the present invention.

[0062] The top cover 300 may be coupled to the top of the module case 200. For example, the top cover 300 may be attached to the top of the module case 200 by being adhered thereto. Specifically, the top cover 300 may be coupled to the top plate 220. The top cover 300 may be attached to the top plate 220 by an adhesive member. Examples of the adhesive member include an adhesive agent and an adhesive tape.

[0063] 5 and 6, at least a portion of the top cover 300 may be configured to be detached from the module case 200 by vent gas or flame discharged from the battery cells 110. Specifically, when thermal runaway occurs in the battery module 10, the adhesive may melt due to the pressure of the gas discharged from the battery cells 110 and / or high heat from dust or flame, thereby weakening the adhesive strength between the module case 200 and the top cover 300. The exhaust pressure of the vent gas discharged in a straight line through the first vent hole H1 acts between the module case 200 and the top cover 300, whose adhesive strength has been weakened, and pushes a portion of the top cover 300 in the exhaust direction of the vent gas, thereby removing it from the module case 200.

[0064] In other words, in a normal state, the top cover 300 can protect the cell stack 100 inside the module case 200 by blocking the first vent hole H1 of the top plate 220 of the module case 200. However, when a thermal event occurs in which vent gas or flames are generated in some of the battery cells 110, at least a portion of the top cover 300 is detached from the module case 200, allowing the vent gas or flames to be smoothly discharged to the outside of the battery module 10 without interfering with the path of the vent gas or flames that are discharged in a straight line through the first vent hole H1 of the top plate 220.

[0065] According to the above-described embodiment of the present invention, a portion of the top cover 300 can be completely removed from the module case 200, and the first vent hole H1 is exposed to the outside of the battery module 10. As a result, the first vent hole H1 is not blocked, and gas, flames, etc. can be completely discharged to the outside of the battery module 10.

[0066] Furthermore, the top cover 300 can prevent gases and flames discharged to the outside from flowing back into the battery module 10. If a portion of the top cover 300 is left behind without being removed from the module case 200 with the adhesive strength of the adhesive member weakened, it not only hinders the discharge of vent gases and flames, but also raises concerns that the gases and flames may penetrate the raised interface between the top cover 300 and the module case 200 and flow back into the battery module 10. However, according to the above embodiment of the present invention, the portion of the top cover 300 with weakened adhesive strength is removed from the module case 200 and does not have any effect on the vent gases or flames, so it is possible to fundamentally prevent gases and flames discharged to the outside from flowing back into the battery module 10.

[0067] The portion of the top cover 300 that remains without being removed from the module case 200 can block not only heat but also high-temperature gas, flame, and discharged matter generated in the battery cells 110. To this end, the top cover 300 may be provided as a pad made of a material with excellent heat resistance and / or fire resistance, such as mica or a fire-resistant barrier (FRB) and silicone. The FRB may include an easily convertible inorganic material and may be made of a material with very high flame and ignition resistance. Therefore, when the FRB and silicone are provided as a pad made of a combined FRB and silicone, they do not shrink and can maintain their shape even when high temperatures are generated, thereby enabling them to stably block high-temperature gas, flame, and the like generated in the battery cells 110.

[0068] As a result, according to the above-described embodiment of the present invention, when thermal runaway occurs in the battery module 10, not only can gas and flames generated inside the battery module 10 be smoothly exhausted to the outside of the battery module 10, but also it can be prevented that the exhausted gas and flames are flowing back into the battery module 10. Therefore, it is possible to minimize the propagation of heat to adjacent battery modules 10 and effectively prevent or delay the propagation of thermal runaway, thereby ensuring the safety and reliability of the battery module 10.

[0069] When a thermal event occurs, at least a portion of the top cover 300 removed from the module case 200 can be deployed at a predetermined localized location, such as a hole, preferably at a position corresponding to the top of the first vent hole H1.

[0070] Specifically, the top cover 300 may include a second vent hole H2. A plurality of the second vent holes H2 may be provided, and each second vent hole H2 may correspond to and cover the first vent hole H1. The second vent hole H2 may be provided at a position where the first vent hole H1 is formed, and may have the same shape and diameter as the first vent hole H1.

[0071] 5, the second vent hole H2 may be configured to be detachable from the top plate 220 by the pressure of vent gas discharged from the battery cell 110. Specifically, when gas is discharged from the first vent hole H1 corresponding to the second vent hole H2, only the second vent hole H2 disposed above the vented battery cell 110 may be disposed to break in the top cover 300. To this end, a notch groove may be formed following the shape of the second vent hole H2.

[0072] Furthermore, the battery module 10 according to the present invention may be assembled in the following order: accommodating the cell stack 100 in the case body 210; completing the exterior of the battery module 10 by welding the top plate 220 and the end plate 230 to the case body 210; applying an adhesive member to the top plate 220; and assembling the top cover 300 thereon. In this case, all portions of the top cover 300 except for the second vent hole H2 may be attached to the top plate 220 with an adhesive member. Specifically, the second vent hole H2 may be disposed in a manner that makes it easy for the second vent hole H2 to break due to the pressure of the vent gas because it is not adhered to the top plate 220 with an adhesive member.

[0073] As a result, according to the above-described embodiment of the present invention, when a thermal event occurs, gases and flames generated within the battery module 10 can be discharged to the outside of the module case 200 through the removed second vent hole H2. At the same time, the remaining second vent hole H2 remains connected to the top plate 220, so that the discharged gases can be prevented from flowing back into the module case 200.

[0074] When a thermal event occurs, at least a portion of the top cover 300 that is removed from the module case 200 may be, for example, a strip-shaped portion that runs along the longitudinal direction of the battery cell 110.

[0075] 3 to 6, the top cover 300 may include a plurality of top cover regions 310. A portion of the second vent hole H2 may be formed in each of the plurality of top cover regions 310. The plurality of top cover regions 310 may be detachably disposed on the top plate 220. Specifically, if an incident occurs in one of the battery cells 110, the second vent hole H2 is first removed due to vent gas generated therein. If a flame is generated inside the module case 200 due to the vent gas or a spark and is exhausted through the first vent hole H1, the adhesive strength between the top cover 300 and the module case 200 may be weakened due to the high heat of the flame, allowing the top cover region 310 disposed on the top of the battery cell 110 to be removed.

[0076] In this case, the top cover 300 may be fabricated as a single unit and arranged so that the plurality of top cover regions 310 can be separated from each other. According to this embodiment of the present invention, costs and time can be reduced and productivity can be improved in manufacturing the battery module 10 compared to when the plurality of top cover regions 310 are fabricated separately and then combined to form a single top cover 300.

[0077] The top cover 300 may include a score line L. The score line L may be provided between the plurality of top cover regions 310. The score line L may be provided as a dashed line or a solid line by forming a groove in a portion of the top cover 300. The score line L may be provided to be weaker than adjacent regions and to be easily broken when the adhesive strength between the top cover 300 and the top plate 220 weakens. The provision of the score line L allows each of the plurality of top cover regions 310 to be broken by gas or flame emitted from any one of the battery cells 110.

[0078] 5, when one of the battery cells 110 is vented, only the top cover region 310 disposed on the vented battery cell 110 among the plurality of top cover regions 310 may be detached from the top plate 220. Furthermore, the remaining top cover regions 310, excluding the detached top cover region 310, may be disposed so as to remain coupled to the top plate 220. For example, as shown in FIG. 5, if a fire occurs in one of the battery cells 110, the adhesive member of the top cover region 310 disposed on the top of the vented battery cell 110 may melt due to the high heat of the flame, weakening the adhesive strength between the top cover region 310 and the top plate 220, thereby allowing only the portion of the top cover 300 disposed on the top of the battery cell 110 to be detached.

[0079] According to the above-described embodiment of the present invention, it is possible to efficiently vent flames present inside the module case 200 to the removed portion of the top cover region 310. Furthermore, according to the above-described embodiment of the present invention, since only a portion of the top cover region 310 is removed, the portion that remains attached to the top plate 220 can prevent gases and flames discharged through the removed top cover region 310 from flowing back into the module case 200.

[0080] FIG. 7 is a perspective view of a top cover according to one embodiment of the present invention.

[0081] The second vent hole H2 may be provided in plurality. The plurality of second vent holes H2 may form a vent hole array A. The vent hole array A may be formed by arranging the second vent holes H2 in a line along the longitudinal direction of the battery cell 110. As shown in FIG. 6 , the vent hole array A may be formed by a plurality of the second vent holes H2 arranged in a line along the Y direction. According to this embodiment of the present invention, even if a thermal event occurs at any position of the battery cell 110, gases and flames generated in the battery cell 110 can be discharged to the outside of the battery module 10 through the second vent hole H2 included in the vent hole array A arranged on the top of the battery cell 110.

[0082] 4 to 7, a plurality of vent hole arrays A may be provided, and the plurality of vent hole arrays A may be arranged side by side in one direction, i.e., the direction in which the battery cells 110 are stacked (X-axis direction). At this time, at least one vent hole array A may be formed in one top cover area 310. According to an embodiment of the present invention, one vent hole array A and one top cover area 310 may be provided to correspond to two or more battery cells 110. At this time, as described above, the first vent hole H1 may be provided to correspond in position and size to the second vent hole H2.

[0083] 4 to 7, in a battery module 10 according to an embodiment of the present invention, a blocking member 120 may be disposed for every two battery cells 110, and one top cover area 310 may be provided on the upper portion between the blocking members 120. One vent hole array A may be formed in such one top cover area 310.

[0084] According to this embodiment, even if a thermal event occurs in one of the two battery cells 110, the specific top cover region 310 in which the vent hole array A is formed and disposed on the upper part of the battery cell 110 can be detached from the top plate 220 by the pressure and / or heat of the vent gas. This allows gas, flames, etc. to be smoothly discharged to the outside of the battery module 10 through the detached top cover region 310.

[0085] Also, with this configuration, gases and flames emitted from the battery cells 110 housed between adjacent blocking members 120 can be discharged to the outside of the module case 200 only through the first vent hole H1 located between the adjacent blocking members 120 and the removed top cover area 310. That is, since the entire outer periphery of the first vent hole H1 is closed, directional venting of gas in the upward direction can be more effectively guided.

[0086] FIG. 8 is a plan view of a battery module according to another embodiment of the present invention, and FIG. 9 is a view illustrating a top cover that is partially removed when thermal runaway occurs in a battery module according to another embodiment of the present invention.

[0087] Meanwhile, in a battery module 10 according to another embodiment of the present invention, two or more vent hole arrays A may be formed in one top cover region 310.

[0088] 8 and 9, in a battery module 10 according to another embodiment of the present invention, a blocking member 120 may be disposed for every two battery cells 110, and one top cover area 310' may be provided on the upper portion between the two blocking members 120. Two vent hole arrays A may be formed in each top cover area 310'. That is, in a battery module 10 according to another embodiment of the present invention, one top cover area 310' may be provided for every four battery cells 110.

[0089] According to this embodiment, when a thermal event occurs in any one battery cell 110, the adjacent battery cells 110 explode one after another, but the more battery cells 110 that correspond to one top cover region 310', the more the internal pressure and / or temperature increases due to gas and flames emitted from the battery cells 110, and the faster the top cover region 310' is detached from the top plate 220. As a result, gas and flames inside the battery module 10 can be more quickly vented to the outside of the module case 200, further ensuring safety.

[0090] FIG. 10 is a schematic perspective view of a battery pack including a battery module according to an embodiment of the present invention.

[0091] 10, a battery pack 1 according to an embodiment of the present invention may include one or more battery modules 10 according to an embodiment of the present invention as described above. The battery pack 1 according to the present invention may further include a battery management system (BMS) for controlling charging and discharging of the one or more battery modules, a current sensor, a fuse, etc., and a pack case 2 for accommodating the above-mentioned components.

[0092] FIG. 11 is a schematic perspective view of a vehicle including a battery pack according to one embodiment of the present invention.

[0093] 11, an automobile 3 according to an embodiment of the present invention may include one or more of the battery pack 1 according to an embodiment of the present invention or the battery module 10 according to an embodiment of the present invention. The automobile 3 according to the present invention may be, for example, an electric vehicle, a hybrid vehicle, or a plug-in hybrid vehicle. The automobile 3 includes a four-wheeled vehicle and a two-wheeled vehicle. The automobile 3 operates by receiving power from the battery pack 1 or the battery module 10 according to an embodiment of the present invention.

[0094] Although the present invention has been described above using limited embodiments and drawings, it should be understood that the present invention is not limited thereby and that those skilled in the art can implement the present invention by making various modifications and variations within the scope of the technical idea of ​​the present invention and the equivalent scope of the appended claims. [Explanation of symbols]

[0095] 1 battery pack 2-pack case 3. Automobiles 10 Battery Module 100 cell stack 110 battery cells 111 Cell Case 112 Electrode Lead 120 Blocking member 200 Module Case 210 Case body 220 Top Plate 230 End Plate 300 top cover 310 Top cover area 310' top cover area 400 Busbar frame assembly 410 Busbar Frame 420 Busbar A Vent hole array H1 First vent hole H2 Second vent hole

Claims

1. a cell stack including a plurality of battery cells; a module case configured to house the cell stack; a top cover coupled to an upper portion of the module case; Including, The battery module, wherein at least a portion of the top cover is configured to be detached from the module case by vent gas or flame discharged from the battery cell.

2. The module case includes: a top plate that forms an upper surface of the module case and has at least one first vent hole formed therein through which vent gas discharged from the battery cell is discharged; The battery module according to claim 1 , wherein the top cover is coupled to the top plate.

3. The battery module according to claim 2 , wherein the top cover is adhered to the top plate.

4. The top cover is 3. The battery module according to claim 2, further comprising at least one second vent hole provided to cover the first vent hole and configured to be detachable from the top plate by pressure of vent gas discharged from the battery cells.

5. the top cover includes a plurality of top cover regions in which some of the second vent holes are formed; The battery module according to claim 4 , wherein the plurality of top cover regions are arranged so as to be separable from each other.

6. The top cover is The battery module according to claim 5 , further comprising score lines disposed between the plurality of top cover regions and configured to allow each of the plurality of top cover regions to be broken.

7. 6. The battery module according to claim 5, wherein, when the battery cell is vented, only a top cover region disposed above the vented battery cell among the plurality of top cover regions is detached from the top plate.

8. The battery module according to claim 7 , wherein the remainder of the plurality of top cover regions are arranged to remain coupled to the top plate.

9. The second vent holes are provided in plural, The battery module according to claim 5 , wherein the plurality of second vent holes form at least one vent hole array arranged in a line along the longitudinal direction of the battery cell.

10. The plurality of battery cells are arranged in a stacked manner in one direction, The battery module according to claim 9 , wherein one vent hole array is arranged to correspond to two or more of the battery cells.

11. The battery module according to claim 10 , wherein the vent hole array is provided in a plurality of holes and arranged along the one direction.

12. The battery module according to claim 11 , wherein at least one of the vent hole arrays is formed in one of the top cover regions.

13. A battery pack comprising the battery module according to any one of claims 1 to 12.

14. A motor vehicle comprising the battery pack of claim 13.

Images