Cover assembly of battery module and battery pack, and vehicle including same

Abstract

Disclosed are a cover assembly of a battery module and a battery pack and vehicle comprising same, the cover assembly comprising: a cover frame which is coupled to an open surface of a battery module case and which closes the battery module case; a plurality of hollows formed so as to extend along the lengthwise direction of the cover frame; a plurality of venting holes formed so as to pass through the cover frame in the direction going toward the inside of the battery module case at points overlapping with the hollows; and venting parts which are inserted into the hollows of the cover frame to close the venting holes, and of which a portion, corresponding to the venting holes, opens when gas or flames are generated in a battery module.

Description

Battery module cover assembly and battery pack and vehicle including the same

[0001] The present invention relates to a cover assembly of a battery module and a battery pack, and a vehicle including the same, which have improved safety through the smooth discharge of gas or flame generated in an abnormal battery situation.

[0002] Recently, technologies for carbon reduction are being actively developed to address environmental issues such as extreme temperatures. To achieve this, energy must be produced using environmentally friendly methods rather than relying on fossil fuels. This energy must be stored as electricity, and the stored electricity must be used in vehicles, various industrial sites, and homes.

[0003] To utilize electric energy for carbon reduction, the use of batteries capable of storing and extracting electric energy is essential. Therefore, ensuring battery performance is essential to sufficiently store electric energy and ensure hassle-free use.

[0004] Batteries primarily utilize redox reactions of metal ions. To increase battery capacity, charge / discharge performance, and efficiency, high-density metal ions are used. Extensive research is also being conducted on electrolyte components and solid electrolytes. However, as battery performance advances, stability generally declines.

[0005] Batteries used in vehicles, industrial applications, and homes are manufactured as physical units called packs. Battery packs contain multiple battery cells within a sealed case, preventing fire from spreading to the outside in the event of a battery overheating or other accident. They also protect the internal battery cells from deterioration caused by the external environment or physical damage.

[0006] A battery pack contains multiple battery cells, housed in an intermediate form called a module or assembly (CMA, Cell Module Assembly). A battery module or assembly is composed of multiple battery cells assembled into a single module or assembly. These modules are then fastened within the pack case, completing the battery pack. Maintenance is facilitated by allowing maintenance to be performed on a module or assembly basis.

[0007] The multiple unit battery cells that make up a module or assembly are comprised of anodes, cathodes, and electrolytes. Because battery cells generate heat during charging and discharging, effective heat dissipation is essential. Furthermore, from the perspective of battery modules, assemblies, and battery packs, designing for efficient heat dissipation is essential to prevent safety accidents.

[0008] Meanwhile, batteries can deteriorate due to manufacturing errors, excessive charging and discharging, and aging. If battery deterioration persists, it can ultimately lead to fire. Therefore, proactive measures are necessary to prevent battery fires. To achieve this, it's crucial to continuously monitor the battery's condition, proactively detect and respond to problems, and minimize damage in the event of an unexpected problem.

[0009] In particular, if a fire breaks out in a specific battery module or battery cell within a battery pack, the gas or flame can easily spread to adjacent battery modules or battery cells because the inside of the battery pack is sealed. Therefore, when a fire breaks out in a specific battery module or battery cell within a battery pack, it is important to ensure smooth gas venting of the battery module or battery cell where the fire broke out, while preventing or delaying the spread of flames to other adjacent battery modules or battery cells.

[0010] The matters described as background technology above are only intended to enhance understanding of the background of the present invention, and should not be taken as an admission that they correspond to prior art already known to those skilled in the art.

[0011] The present invention has been proposed to solve such problems, and provides a cover assembly for inserting a venting part into the interior of a cover frame in which a hollow and venting hole are formed when a fire occurs in a specific battery module or battery cell, thereby preventing the cover of the battery module from being lifted when a fire occurs, thereby facilitating the discharge of gas or flame from a battery module or battery cell in which a fire has occurred and preventing the spread of gas or flame to an adjacent battery module or battery cell, and a battery pack and a vehicle including the same for a battery module.

[0012] The technical problems to be achieved in the present invention are not limited to the technical problems mentioned above, and other technical problems not mentioned can be clearly understood by a person having ordinary skill in the technical field to which the present invention belongs from the description below.

[0013] In order to achieve the above object, a cover assembly of a battery module according to the present invention comprises: a cover frame coupled to an open side of a battery module case to close the battery module case; a plurality of hollow portions formed to extend along a longitudinal direction inside the cover frame; a plurality of venting holes formed to penetrate the cover frame in a direction toward the inside of the battery module case at points overlapping the hollow portions; and a venting portion inserted into the hollow portion of the cover frame to close the venting holes, and having a portion corresponding to the venting holes opened when gas or flame is generated in the battery module.

[0014] In the case of the cover assembly of the battery module according to the present invention, the hollow portion extends to the end of the cover frame, and the venting portion can be inserted into the hollow portion through the end of the hollow portion.

[0015] In the case of the cover assembly of the battery module according to the present invention, a plurality of hollow parts can be arranged spaced apart from each other in parallel inside the cover frame.

[0016] In the case of the cover assembly of the battery module according to the present invention, a plurality of venting parts are provided, and the plurality of venting parts can be individually inserted into each hollow portion to be combined with the cover frame.

[0017] In the case of the cover assembly of the battery module according to the present invention, the venting hole is composed of a first hole formed on the inner surface of the cover frame and a second hole formed on the outer surface of the cover frame, and the first hole and the second hole can be connected to each other through the hollow space.

[0018] In the case of the cover assembly of the battery module according to the present invention, the second hole may have a wider width than the first hole.

[0019] In the case of the cover assembly of the battery module according to the present invention, a break portion that opens when gas or flame is generated in the battery module is formed in the venting portion, and the first hole and the second hole are formed to face each other with a hollow space therebetween, so that the break portion can be placed between the first hole and the second hole.

[0020] In the case of the cover assembly of the battery module according to the present invention, the broken portion may have a width greater than the first hole and a width smaller than the second hole.

[0021] In the case of the cover assembly of the battery module according to the present invention, the cover frame can be formed of a metal material.

[0022] In the case of the cover assembly of the battery module according to the present invention, the cover frame can be formed through an extrusion method so that a hollow space is integrally formed inside.

[0023] In the case of the cover assembly of the battery module according to the present invention, the venting hole can be formed by drilling a hole in the extruded cover frame.

[0024] In the case of the cover assembly of the battery module according to the present invention, the venting hole is formed by forming a first hole formed on the inner surface of the cover frame and a second hole formed on the outer surface of the cover frame, and the second hole can be formed to have a wider width than the first hole through additional processing.

[0025] In the case of the cover assembly of the battery module according to the present invention, the hollow end is deformed by being pressurized while the venting part is inserted, thereby preventing the venting part from coming off.

[0026] In the case of the cover assembly of the battery module according to the present invention, a cross-sectional cover is formed at the hollow end, and the venting portion inserted into the hollow can be prevented from coming out of the cover frame by the cross-sectional cover.

[0027] In the case of the cover assembly of the battery module according to the present invention, the hollow end is welded and closed with the venting part inserted, thereby preventing the venting part from coming out of the cover frame.

[0028] In the case of the cover assembly of the battery module according to the present invention, the venting part can be formed of a fire-resistant material.

[0029] In the case of the cover assembly of the battery module according to the present invention, a cut line may be formed in the venting portion along the shape of the venting hole.

[0030] In the case of the cover assembly of the battery module according to the present invention, when gas or flame is generated in the battery module, the venting part may be cut along the cut line and a portion corresponding to the venting hole may be opened, thereby forming a through hole.

[0031] In the case of the cover assembly of the battery module according to the present invention, the through hole of the venting portion may have a wider width than the first hole and a narrower width than the second hole.

[0032] In the case of the battery pack according to the present invention, a cover assembly of the battery module as described above is included.

[0033] In the case of a vehicle according to the present invention, the battery pack as described above is included.

[0034] According to the cover assembly of the battery module of the present invention, the battery pack and the vehicle including the same, when a fire occurs in a specific battery module or battery cell, the module cover is prevented from being lifted by inserting a venting part into the cover frame in which a hollow and venting hole are formed, thereby preventing the spread of gas or flame to adjacent battery modules or battery cells and simultaneously facilitating venting of gas or flame from the problematic battery module or battery cell, thereby improving the safety of the entire upper system utilizing the cover assembly of the battery module.

[0035] The effects that can be obtained from the present invention are not limited to the effects mentioned above, and other effects not mentioned can be clearly understood by a person having ordinary skill in the art to which the present invention belongs from the description below.

[0036] FIG. 1 is a drawing showing a cover assembly of a battery module according to one embodiment of the present invention.

[0037] Figure 2 is an enlarged drawing of part A shown in Figure 1.

[0038] Fig. 3 is a drawing showing a cross-section of the cover frame illustrated in Fig. 1.

[0039] Fig. 4 is a drawing showing a state in which a venting part is inserted into the inside of the cover frame illustrated in Fig. 1.

[0040] Fig. 5 is a drawing showing a cross-section of the CC' portion illustrated in Fig. 4.

[0041] Fig. 6 is a drawing showing a cross-section of the B-B' portion shown in Fig. 4.

[0042] Fig. 7 is a drawing showing a cross-section of the incision line shown in Fig. 4 in an open state.

[0043] Fig. 8 is a drawing showing a state in which a cross-sectional cover is formed on a cross-section of the cover frame illustrated in Fig. 1.

[0044] FIG. 9 is a drawing showing a method for forming a venting hole according to one embodiment of the present invention.

[0045] FIG. 10 is a drawing showing a method for forming a venting hole according to another embodiment of the present invention.

[0046] Fig. 11 is a drawing showing a cross-section of a venting hole formed by the method according to Figs. 9 and 10.

[0047] FIG. 12 is a drawing showing a method of forming a first hole and a second hole according to one embodiment of the present invention after the method according to FIGS. 9 and 10.

[0048] Fig. 13 is a drawing showing a cross-section of the first hole and the second hole formed by the method according to Fig. 12.

[0049] Fig. 14 is a drawing showing a battery pack and a vehicle to which the cover assembly of the battery module of the present invention is applied.

[0050] In describing the embodiments disclosed in this specification, detailed descriptions of related known technologies will be omitted if it is determined that such detailed descriptions may obscure the gist of the embodiments disclosed in this specification. In addition, the attached drawings are provided solely to facilitate understanding of the embodiments disclosed in this specification, and the technical concepts disclosed in this specification are not limited by the attached drawings, and should be understood to include all modifications, equivalents, and substitutes included within the spirit and technical scope of the present invention.

[0051] Terms including ordinal numbers, such as first, second, etc., may be used to describe various components, but the components are not limited by the terms. The terms are used solely to distinguish one component from another. Singular expressions include plural expressions unless the context clearly indicates otherwise. In this specification, it should be understood that terms such as "comprises" or "has" are intended to specify the presence of a feature, number, step, operation, component, part, or combination thereof described in the specification, but do not preclude the presence or addition of one or more other features, numbers, steps, operations, components, parts, or combinations thereof.

[0052] The suffixes "module" and "part" used for components in the following description are assigned or used interchangeably solely for the convenience of writing specifications, and do not in themselves have distinct meanings or roles. When a component is referred to as being "connected" or "connected" to another component, it should be understood that while it may be directly connected or connected to that other component, there may also be other components present in between. Conversely, when a component is referred to as being "directly connected" or "directly connected" to another component, it should be understood that there are no other components present in between.

[0053] Hereinafter, embodiments disclosed in the present specification will be described in detail with reference to the attached drawings. Regardless of the drawing numbers, identical or similar components will be given the same reference numbers and redundant descriptions thereof will be omitted. Battery cells are the most basic units that constitute a battery, and a phenomenon in which the temperature of a battery cell becomes excessively high and explodes or catches fire is called thermal runaway. In addition, when thermal runaway that occurs in one battery cell emits enormous heat and spreads to adjacent battery cells, it is called thermal propagation. Therefore, in order to prevent battery explosion, it is important to prepare a technology that prevents or maximally prevents thermal propagation when thermal runaway occurs in one battery cell.

[0054] Thermal runaway in a battery cell or a battery module composed of multiple battery cells can be caused by various factors, including physical factors such as corrosion, collision, and deformation of the battery, electrical factors such as short circuits from the outside, overcharging or overdischarging of the battery itself, and thermal factors such as an increase in the temperature of the battery cell due to an external heat source.

[0055] If thermal runaway occurs in a battery, fire or explosion can occur. This can lead to thermal spread, which can spread to adjacent battery modules or cells. Responding to thermal spread is extremely challenging due to its high fire intensity and the risk of subsequent explosions. Therefore, technologies are needed to prevent thermal spread before it occurs.

[0056] In the past, when thermal runaway occurred in a battery module having multiple battery cells built in or in a battery cell built in a battery module, there was a problem in that the cover of the battery module was lifted in the high temperature and high pressure environment caused by the thermal runaway, causing flames or gases to spread to adjacent battery modules or battery cells, and preventing smooth venting of gases or flames from the battery module or battery cell where the thermal runaway occurred.

[0057] The present invention proposes a cover assembly for a battery module in which a venting portion (500) made of a refractory material is inserted into the cover frame (300) of a battery module in which a hollow portion (360) and a venting hole (340) are formed, thereby preventing the cover of the battery module from being lifted, thereby preventing or delaying heat transmission to an adjacent battery module or battery cell even if heat runaway occurs in the battery module or battery cell.

[0058] Specifically, the cover assembly of the battery module of the present invention is composed of a cover frame (300) and a venting portion (500) as shown in FIG. 1. The cover frame (300) has a plurality of hollows (360) formed therein, and the venting portion (500) is inserted into the hollows (360) through the ends (320) of the hollows (360). In addition, the cover frame (300) has a venting hole (340) formed therein that penetrates the cover frame (300) in a direction toward the inside of the battery module case (100) at a point overlapping the hollows (360), thereby allowing gas or flames to be discharged to the outside through the venting hole (340) in the event of thermal runaway in the battery module or battery cell. The end (320) of the hollow (360) and the venting hole (340) are connected through the hollow (360), so that when the venting part (500) is inserted into the hollow (360) through the end (320) of the hollow (360), the venting hole (340) is closed and the portion corresponding to the venting hole (340) is exposed to the outside.

[0059] The venting part (500) is inserted into the hollow part (360) of the cover frame (300) as shown in Fig. 1 to close the venting hole (340), and is configured so that a part corresponding to the venting hole (340) is opened when gas or flame is generated in the battery module. The venting part (500) is inserted into the cover frame (300) and coupled thereto. Since the venting part (500) is inserted into the cover frame (300) and coupled in this way, even when thermal runaway occurs in a specific battery module or battery cell, the cover of the battery module does not lift off, so that the venting of gas or flame in the battery module or battery cell where thermal runaway occurs is smoothly performed, and heat transmission to adjacent battery modules or battery cells can be prevented.

[0060] As shown in FIG. 1, a plurality of hollows (360) are formed inside the cover frame (300) of the cover assembly of the battery module, and the plurality of hollows (360) are arranged to be spaced apart from each other in parallel inside the cover frame (300). Accordingly, a plurality of venting parts (500) inserted into the hollows (360) are also provided, and the plurality of venting parts (500) are individually inserted into each hollow (360) to be combined with the cover frame (300). That is, the venting parts (500) are formed in a single line shape, such as an individual line, which is inserted into the hollow (360) formed in the longitudinal direction of the cover assembly of the battery module through the end (320) of the hollow (360), as shown in FIG. 2, and each venting part (500) is individually inserted into the hollow (360) through the end (320) of the hollow (360), thereby being combined with the cover assembly of the battery module.

[0061] The venting portion (500) is inserted into the hollow (360) through the end (320) of the hollow (360) of the cover frame (300) and is combined with the cover frame (300) inside the cover frame (300). Since the venting portion (500) has a single line shape, it can be inserted by sliding when inserted into the hollow (360) through the end (320) of the hollow (360), and can be combined with the inside of the cover frame (300) by being inserted into the hollow (360) through the end (320) of the hollow (360) through a mechanical method such as a fitting.

[0062] Since the venting parts (500) are individually provided and each is individually inserted into the hollow (360), even if one venting part (500) is opened during thermal runaway in a specific battery module or battery cell, the thermal transfer phenomenon in which thermal runaway is transferred to the adjacent venting part (500) can be prevented. Referring to Fig. 7, even if thermal runaway occurs in a battery cell where the venting part (500) on the left is arranged, the right venting part (500) will not be opened because it is individually inserted and connected to the adjacent venting part (500) arranged on the right. Accordingly, in the case where thermal runaway occurs at the location of the venting portion (500) on the left, the venting portion (500) on the left opens the rupture portion (560) to form a through hole (580), thereby smoothly discharging gas or flames, and at the same time, the adjacent venting portion (500) located on the right can prevent the transfer of gas or flames because the rupture portion (560) is still not opened, thereby preventing or delaying the heat transfer phenomenon inside the battery module.

[0063] The venting hole (340) is formed to penetrate the cover frame (300) and is specifically composed of a first hole (342) formed on the inner surface of the cover frame (300) and a second hole (344) formed on the outer surface of the cover frame (300) as shown in FIG. 3. The first hole (342) and the second hole (344) are connected to each other through a hollow (360) at positions facing each other, and the second hole (344) has the characteristic of being larger in width and size than the first hole (342). By forming a first hole (342) and a second hole (344) in the cover frame (300), the venting portion (500) can be inserted into the hollow space (360) and fixed between the first hole (342) and the second hole (344), and by making the sizes of the first hole (342) and the second hole (344) different, even if thermal runaway occurs in a specific battery module or battery cell, the venting portion (500) cannot pass through the first hole (342), thereby preventing the venting portion (500) from flowing back into the battery module.

[0064] A rupture portion (560) that is opened by gas or flame generated when the battery module runs away in thermal runaway is formed in the venting portion (500), as shown in FIG. 4. The rupture portion (560) is a portion that is opened along a cut line (520) formed in the venting portion (500), and is formed at a position corresponding to the venting hole (340) of the cover frame (300). Since the first hole (342) and the second hole (344) of the cover frame (300) are formed to face each other with the hollow (360) therebetween, the rupture portion (560) is also positioned between the first hole (342) and the second hole (344).

[0065] The fracture portion (560) must be fixed between the first hole (342) and the second hole (344) as shown in FIG. 5, and in the event of thermal runaway in a specific battery module or battery cell, the fracture portion (560) must be larger in width or size than the first hole (342) and smaller in width or size than the second hole (344) so ​​that the venting portion (500) pieces or gas or flames opened by the fracture portion (560) must not flow back into the battery module but must be discharged to the outside. By making the width or size of the rupture portion (560) and the first hole (342) and the second hole (344) different in this way, even if thermal runaway occurs in a specific battery module or battery cell, pieces of the venting portion (500) with the rupture portion (560) open cannot pass through the smaller first hole (342), thereby preventing pieces of the venting portion (500) from being reversely introduced into the battery module or battery cell and damaging the internal device.

[0066] The cover frame (300) is preferably formed of a metal material that is the same or similar to the battery module case (100) because it closes and joins an open side of the battery module case (100) as shown in FIG. 1. In addition, the cover frame (300) constitutes a part of the battery module case (100), and since the battery module case (100) is a component constituting the vehicle (V), it may be formed of aluminum, which is easy to form and has excellent durability, among metals, in order to prepare for various abnormal situations such as external impact or fire inside the battery.

[0067] When manufacturing a cover frame (300), it can be formed by extrusion so that multiple hollows (360) are integrally formed inside. The hollows (360) must be positioned at locations corresponding to where battery cells are located inside the battery module within the cover frame (300) and the multiple hollows (360) must be formed to be spaced apart from each other in parallel. Therefore, if the cover frame (300) is first extruded and then the hollows (360) are formed through post-processing, an error may occur between the location of the hollows (360) inside the cover frame (300) and the location of the battery cells inside the battery module. As a result, gas or flames may not be smoothly vented during thermal runaway, heat transfer to adjacent battery modules or battery cells cannot be prevented, and it is also disadvantageous in terms of cost.

[0068] However, the venting hole (340) formed in the cover frame (300) can be formed through post-processing after the cover frame (300) is formed integrally through an extrusion method with a hollow body (360). The venting hole (340) can be post-processed by processing the surface of the cover frame (300) to form a hole (340) inside. As a post-processing method, the hole can be processed through a device (700) that forms a hole (340) by polishing the inside of the cover frame (300), or a method of forming a venting hole (340) by punching the inside of the cover frame (300) using a punching means, etc. FIG. 9 is a drawing showing the formation of a venting hole (340) using a device (700) that forms a hole (340) by grinding or cutting the inside of a cover frame (300), and FIG. 10 is a drawing showing the formation of a venting hole (340) using a punching means or a press machine. Of course, the method of forming the venting hole (340) is not limited to the illustrated embodiment, as long as a hole (340) that connects the inside and the outside is formed on the surface of the cover frame (300).

[0069] As mentioned above, the venting hole (340) is composed of a first hole (342) formed on the inner surface of the cover frame (300) and a second hole (344) formed on the outer surface of the cover frame (300). In the case of post-processing the venting hole (340) as shown in FIGS. 9 and 10, a single venting hole (340) having the same size that penetrates both the inner and outer surfaces of the cover frame (300) is formed as shown in FIG. 11, so that a difference in width or size between the first hole (342) and the second hole (344) must be formed thereafter. Accordingly, as shown in FIG. 12, the hole corresponding to the second hole (344), which is the outer portion of the cover frame (300), can be formed to have a larger width or size than the first hole (342) through additional processing. As a result, as shown in Fig. 13, since the first hole (342) and the second hole (344) have a difference in size, the venting part (500) can be fixed between the first hole (342) and the second hole (344), and even in the event of thermal runaway, it is possible to prevent a piece of the open venting part (500) or gas or flame from flowing back into the interior of the first hole (342).

[0070] A plurality of hollows (360) are formed inside the cover frame (300), and the hollows (360) extend in the longitudinal direction of the cover frame (300) as shown in FIG. 1, and the end (320) of the hollows (360) has a hole shape into which a venting part (500) can be inserted at the point where it meets the cover frame (300), as shown in FIG. 2. After the venting part (500) is inserted into the end (320) of the hole-shaped hollow (360), it is necessary to prevent the venting part (500) from being detached again to the end (320) of the hollow (360) in order to connect the cover frame (300) and the venting part (500).

[0071] Therefore, by deforming the end (320) of the hollow (360) with the venting part (500) inserted by applying pressure, the venting part (500) can be prevented from coming off. The cover frame (300) is made of a metal material formed through an extrusion method so that the hollow (360) is integrally formed inside, and after the venting part (500) is inserted into the cover frame (300), the insertion point of the venting part (500), which is the end of the cover frame (300) and the end (320) of the hollow (360), is pressed by a pressurizing means such as a press to block the end (320), thereby preventing the venting part (500) from coming off from the cover frame (300).

[0072] There is also a method of preventing the venting part (500) from being separated from the cover frame (300) by using a cross-section cover (900) as shown in FIG. 8 after the venting part (500) is inserted into the hollow (360) through the end (320) of the hollow (360) and is combined with the cover frame (300). As shown in FIG. 2, the end (320) of the hollow (360) is in the shape of a small hole formed on one or both sides of the cover frame (300), so that after the venting part (500) is inserted into the hollow (360) through the end (320) of the hollow (360), the cross-section cover (900) is placed on the small hole shape to block the end (320) of the hollow (360), thereby preventing the venting part (500) from being separated from the cover frame (300).

[0073] In this case, the cross-sectional cover (900) may use an individual cap-shaped stopper that blocks the end (320) of each hollow (360) as shown in FIG. 8, or may use a stopper in which a plurality of cap shapes are arranged in a band shape to match the spacing between the ends (320) of the hollow (360). If the venting portion (500) can be prevented from being separated from the cover frame (300) by blocking the end (320) of the hollow (360), cross-sectional covers (900) of various shapes other than the cap shape or the band shape may be considered.

[0074] Since the cover frame (300) is formed of a metal material, after the venting part (500) is inserted through the end (320) of the hollow (360), the end (320) of the hollow (360) can be closed by welding or an adhesive, etc. In the case of an adhesive, if it melts in a high temperature and high pressure environment during thermal runaway, the end (320) of the hollow (360) cannot be properly closed, so an adhesive made of a fire-resistant material can be used. In addition, since the cover frame (300) is formed of a metal material and the end (320) of the hollow (360) has a small hole shape, the end (320) of the hollow (360) can also be closed by welding. In this way, by preventing the venting part (500) from being detached from the cover frame (300) after being inserted into the hollow (360) using a method such as adhesive or welding, the bonding force between the cover frame (300) and the venting part (500) is further increased, thereby preventing the battery module cover from being lifted even when thermal runaway occurs.

[0075] The venting portion (500) is formed of a refractory material and is inserted into the hollow portion (360) through the end portion (320) of the hollow portion (360) and combined with the cover frame (300). When inserted into the interior of the cover frame (300), it is inserted as a single, single-line unit as shown in FIG. 4. As shown, since the venting portions (500) are inserted as a single, single-line unit, even if thermal runaway occurs, each venting portion (500) is individually opened and closed, so that even if one venting portion (500) is opened due to gas or flame, the propagation of gas or flame to an adjacent, closed venting portion (500) can be prevented. Each venting section (500) is individually inserted through the end (320) of the hollow section (360) in the smallest unit such as a line, and after being inserted, it is prevented from being separated from the cover frame (300) by various methods such as a pressurizing means, a cross-sectional cover (900), an adhesive, or welding, and is combined with the cover frame (300).

[0076] The venting portion (500) may be formed of a heat-resistant material such as mica (a mica material) to prevent gas or flames caused by thermal runaway in a specific battery module or battery cell from spreading to adjacent battery modules or battery cells. The venting portion (500) is inserted into the cover frame (300) in the longitudinal direction when the hollow portion (360) is formed in the longitudinal direction of the battery module as shown in FIG. 1, but may be inserted in the width direction of the cover frame (300) in some cases. If each venting portion (500) can be individually controlled, the cover assembly of the battery module may be configured by individually inserting the venting portions (500) into the cover frame (300) using new units such as two or more rows instead of one row.

[0077] Meanwhile, a cut line (520) is formed in the venting portion (500) as shown in FIG. 4. The cut line (520) is formed along the shape of the venting hole (340), and the cut line (520) has a discontinuous shape with a non-cut portion (540) formed in the middle. The cut line (520) is a portion that is cut and opened in a high temperature or high pressure environment when a thermal runaway occurs in a battery module or a battery cell as shown in FIGS. 6 and 7, and when gas or flame occurs in the battery module or the battery cell, the cut line (520) of the venting portion (500) is cut, and a rupture portion (560), which is a portion corresponding to the venting hole (340), is opened, thereby forming a through hole (580). The through hole (580) of the venting portion (500) is formed to have a width or size larger than the first hole (342) formed on the inner surface of the cover frame (300) and a width or size smaller than the second hole (344) formed on the outer surface of the cover frame (300), as shown in FIG. 7, so that even if thermal runaway occurs, the venting portion (500) is prevented from flowing back into the battery module or battery cell.

[0078] FIG. 7 is a drawing showing a state in which thermal runaway occurs on the side of some of the venting parts (500) because the venting parts (500) are each inserted individually. As shown, when thermal runaway occurs in the venting hole (340) where the venting part (500) on the left side exists, the venting part (500) is opened along the cut line (520) due to gas or flame, and at this time, the cut line (520) is cut along the fracture part (560) corresponding to the venting hole (340), so that the opened venting part (500) piece is prevented from flowing back into the inside of the first hole (342) due to the fracture part (560) which is larger than the first hole (342). In addition, a through hole (580) is formed in the place where the fracture portion (560) is opened, and since the through hole (580) is also opened along the incision line (520), it is larger than the first hole (342) and smaller than the second hole (344). Even if thermal runaway occurs in the venting hole (340) shown on the left in the drawing, the venting portion (500) shown on the right is inserted and controlled separately from the left venting portion (500), so the right venting portion (500) is not opened together with the left venting portion (500). In addition, since the right venting part (500) is inserted into the cover frame (300) separately from the left venting part (500), even if thermal runaway occurs in the left venting part (500), the right venting part (500) still closes the venting hole (340), so that gas or flame or pieces of the venting part (500) discharged from the left venting hole (340) do not flow in through the right venting hole (340), thereby preventing or delaying the heat transfer phenomenon as much as possible.

[0079] Meanwhile, the cover assembly of the battery module according to the present invention can be applied to battery packs (BP) of various vehicles (V) such as internal combustion engine vehicles, electric vehicles, hybrid vehicles, and fuel cell vehicles, as shown in FIG. 14, and in addition to vehicles (V), it can be applied to battery packs (BP) of various fields such as industrial ESS (Energy Storage System), household ESS, and small battery packs.

[0080] Although the present invention has been illustrated and described with respect to specific embodiments thereof, it will be apparent to those skilled in the art that the present invention may be variously improved and modified without departing from the technical spirit of the present invention as defined by the following claims.

Claims

1. A cover frame coupled to an open side of a battery module case to close the battery module case; A plurality of hollow spaces formed extending along the length direction inside the above cover frame; A plurality of venting holes formed to penetrate the cover frame in a direction toward the inside of the battery module case at a point overlapping the hollow; and A cover assembly of a battery module, comprising a venting part inserted into the hollow portion of the cover frame to close the venting hole, and a portion corresponding to the venting hole being opened when gas or flame is generated in the battery module.

2. In claim 1, A cover assembly of a battery module, characterized in that the hollow extends to the end of the cover frame, and the venting portion is inserted into the interior of the hollow through the end of the hollow.

3. In claim 1, The above plurality of hollows are arranged parallel to each other and spaced apart from each other inside the cover frame, A cover assembly of a battery module, characterized in that a plurality of the above venting parts are provided, and the plurality of the above venting parts are individually inserted into each hollow portion and thus combined with the cover frame.

4. In claim 1, The above venting hole includes a first hole formed on the inner surface of the cover frame and a second hole formed on the outer surface of the cover frame, and the first hole and the second hole are connected to each other through the hollow, A cover assembly of a battery module, characterized in that the second hole has a wider width than the first hole.

5. In claim 4, The venting portion is formed with a break portion that opens when gas or flame is generated in the battery module, and the first hole and the second hole are formed to face each other with the hollow space therebetween, so that the break portion is arranged between the first hole and the second hole. A cover assembly of a battery module, characterized in that the above-mentioned broken portion has a width greater than the first hole and a width smaller than the second hole.

6. In claim 1, The above cover frame is molded from a metal material, The above cover frame is formed through an extrusion process so that the hollow part is formed integrally inside. A cover assembly of a battery module, characterized in that the above venting hole is formed by drilling a hole in an extruded cover frame.

7. In claim 6, A cover assembly of a battery module, characterized in that the venting hole is formed by forming a first hole formed on the inner surface of the cover frame and a second hole formed on the outer surface of the cover frame, and the second hole is formed to have a wider width than the first hole through additional processing.

8. In claim 1, A cover assembly of a battery module, characterized in that the hollow end is deformed by being pressurized while the venting part is inserted, thereby preventing the venting part from coming off.

9. In claim 1, A cover assembly of a battery module, characterized in that a cross-sectional cover is formed at the end of the hollow portion, and the venting portion inserted into the hollow portion is prevented from coming out of the cover frame by the cross-sectional cover.

10. In claim 1, A cover assembly of a battery module, characterized in that the hollow end is welded and closed while the venting part is inserted, thereby preventing the venting part from coming out of the cover frame.

11. In claim 1, A cover assembly of a battery module, characterized in that the above venting part is formed of a fire-resistant material.

12. In claim 1, In the above venting section, a cut line is formed along the shape of the venting hole, A cover assembly of a battery module, characterized in that when gas or flame is generated in the battery module, the above-mentioned venting part is cut through the cut line and a portion corresponding to the above-mentioned venting hole is opened, thereby forming a through hole.

13. In claim 12, The venting hole of the above venting part includes a first hole formed on the inner surface of the cover frame and a second hole formed on the outer surface of the cover frame, A cover assembly of a battery module, characterized in that the through hole of the venting portion has a wider width than the first hole and a narrower width than the second hole.

14. A battery pack characterized by including a cover assembly of the battery module of claim 1.

15. A vehicle characterized by including the battery pack of claim 14.

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