Battery module with sealing pad

Abstract

Battery module (10), including: a plurality of battery cells (110); a housing (200) accommodating the plurality of battery cells (110) in an internal accommodating space and including a bent portion (c) bent with a predetermined curvature; and a sealing pad (500) attached to the housing (200) to be at least partially in contact with the bent portion, wherein the sealing pad (500) includes: a pad body (510) which at least partially coincides with the bent portion (c); and a stress-relieving portion (530) disposed in a portion (410) of the pad body (510) corresponding to the bent portion and dispersing a stress in a portion (410) thereof corresponding to the bent portion (c).

Description

TECHNICAL FIELD

[0001] The present disclosure relates to a battery module including a sealing pad. BACKGROUND

[0002] Secondary batteries have the advantage that, unlike primary batteries, they can be charged or discharged with electricity, and thus receive significant attention as an energy source for various mobile devices and electric vehicles.

[0003] These secondary batteries may include battery cells in which an electrode assembly formed by stacking a cathode plate, an anode plate, and a separator or by winding them in a roll form is housed within a casing. A plurality of battery cells may be stacked in a predetermined direction and housed in a battery module or a battery pack.

[0004] Meanwhile, the casing of the battery module or battery pack can be formed into various shapes, such as convex curved, depending on the specifications. In this case, if an adhesive structure is arranged on the convex portion described above, stress can be concentrated on the convex portion, thus reducing adhesion therebetween. SUMMARY

[0005] According to one aspect of the present disclosure, a battery module is provided in which a sealing pad attached to a housing can be prevented from peeling off.

[0006] According to one aspect of the present disclosure, a battery module is provided including a sealing pad having excellent adhesiveness regardless of a shape of the case.

[0007] A battery module of the present disclosure can be widely applied to electric vehicles, battery charging stations, and devices in green technology fields such as solar power generation and wind power generation that use other batteries. Additionally, the battery module of the present disclosure can be used in environmentally friendly electric vehicles, hybrid vehicles, or the like to prevent climate change by suppressing air pollution and greenhouse gas emissions.

[0008] A battery module of the present disclosure may include: a plurality of battery cells; a casing that accommodates the plurality of battery cells in an internal accommodation space and includes a bent portion bent with a predetermined curvature; and a sealing pad attached to the casing to at least partially contact the bent portion, the sealing pad including: a pad body that at least partially coincides with the bent portion; and a stress-relieving portion that is disposed in a portion of the pad body that coincides with the bent portion and disperses a stress in a portion thereof that coincides with the bent portion.

[0009] In one embodiment, the housing may include a terminal hole through which the receiving space communicates with an exterior of the housing, and the sealing pad may be arranged to surround at least a portion of a vicinity of the terminal hole.

[0010] In one embodiment, the bent portion may be formed in the vicinity of the terminal hole.

[0011] In one embodiment, the curved portion may be convex toward the receiving space.

[0012] In one embodiment, the pad body may include a first surface facing and in contact with the housing and a second surface opposite the first surface and facing the receiving space, and the stress-relieving portion may be formed on the second surface.

[0013] In one embodiment, the first surface of the pad body may be arranged to be at least partially in contact with the bent portion.

[0014] In one embodiment, the stress-relieving portion may include at least one notched groove formed by deepening at least a portion thereof in a direction oriented from the second surface toward the first surface.

[0015] In one embodiment, the at least one notch groove may be arranged to face the bent portion.

[0016] In one embodiment, the bent portion may be convex in a direction oriented toward the at least one notch groove.

[0017] In one embodiment, the stress-relieving portion may include a plurality of notched grooves arranged in a predetermined pattern.

[0018] In one embodiment, the plurality of notched grooves may form a predetermined pattern arranged in one or more rows in a predetermined direction.

[0019] In one embodiment, the battery module may further include: a bus bar assembly electrically connected to the plurality of battery cells; and a terminal portion electrically connected to the bus bar assembly and exposed to the exterior of the housing through the terminal hole, and the sealing pad may be arranged to at least partially surround the terminal portion in the vicinity of the terminal hole.

[0020] In one embodiment, the housing may further include: a lower cover supporting the plurality of battery cells; and an upper cover arranged to face the lower cover, and the terminal hole may be arranged in the upper cover.

[0021] In one embodiment, the receiving space may be provided to allow a fluid to be injected, and the sealing pad may be provided to prevent the fluid from leaking through the port hole.

[0022] In one embodiment, the fluid may include a liquid foam that prevents or extinguishes fire, and the sealing pad may be provided to prevent the liquid foam injected into the receiving space from leaking out.

[0023] In one embodiment, the pad body may be arranged such that at least a portion of the pad body is in contact with the bent portion, and the stress-relieving portion may be arranged to face the bent portion.

[0024] In addition, a battery module of the present disclosure may include: a plurality of battery cells; a casing that accommodates the plurality of battery cells in a receiving space and includes a through-hole penetrating the casing to communicate with the outside, and a bent portion convexly bent in a vicinity of the through-hole toward the receiving space; and a sealing pad arranged to surround at least a portion of the through-hole, and a liquid foam provided for preventing a fire or extinguishing a fire may be injected into the receiving space of the casing. The sealing pad may be provided to prevent the liquid foam from leaking out of the casing through the through-hole, and the sealing pad may include: a pad body arranged to at least partially contact the bent portion;and a stress-relieving portion provided in the pad body to face the bent portion and to disperse a stress applied to the pad body by the bent portion;

[0025] In one embodiment, the stress-relieving portion may include at least one notched groove formed by recessing at least a portion thereof in the pad body.

[0026] As described above, the solution according to the present disclosure has been described, but this is exemplary, and it should be understood that even if other components not mentioned here are added, they belong to the present disclosure.

[0027] According to an embodiment of the present disclosure, it may be possible to provide a battery module in which a sealing pad attached to a housing can be prevented from peeling off.

[0028] According to an embodiment of the present disclosure, it may be possible to provide a battery module including a sealing pad having excellent adhesiveness regardless of a shape of the case. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] Certain aspects, features and advantages of the present disclosure are illustrated by the following detailed description with reference to the accompanying drawings. Fig. 1 is a perspective view of a battery module according to an embodiment of the present disclosure. Fig. 2 is a perspective exploded view of a battery module according to an embodiment of the present disclosure. Fig. 3 is an enlarged view of part A of Fig. 2. Fig. 4 is an enlarged view of part B of Fig. 3. Fig. 5 is a cross-sectional view in a Y-axis direction in Fig. 3. Fig. 6 is a view of a sealing pad according to one embodiment. Fig. 7 is a view of a sealing pad according to another embodiment. DETAILED DESCRIPTION

[0030] Before describing the embodiments in detail, it should be understood that the terms used in the specification and the appended claims should not be construed as being limited to generic and dictionary-like meanings, but should be interpreted based on the meanings and concepts corresponding to the technical aspects of the present disclosure based on the principle that the inventor is allowed to appropriately define terms for the best explanation.

[0031] The same reference numerals or symbols described in each drawing represent components or elements that perform substantially the same functions. For ease of description and understanding, the same reference numerals or symbols may be used in different embodiments.

[0032] Unless expressly stated otherwise in the phrase, the singular includes the plural. It is further understood that the terms "consists of," "consisting of," "includes," and / or "including," when used herein, indicate the presence of specified features, integers, steps, operations, elements, and / or components, but do not preclude the presence or addition of one or more other features, integers, steps, operations, elements, components, and / or groups thereof.

[0033] In addition, it should be noted in advance that the terms such as "above", "upper", "below", "below", "lower", "side", "front" and "back" are based on the direction illustrated in the drawings and may be expressed differently when the direction of the object is changed.

[0034] Additionally, in the present description and claims, terms including ordinal numbers such as "first" and "second" may be used to distinguish between components. These ordinal numbers are used to distinguish the same or similar components from one another, and the meaning of the terms should not be construed as limited by the use of these ordinal numbers. For example, the components combined with these ordinal numbers should not be construed as limiting the order of use or arrangement of the components. If necessary, the ordinal numbers may be used interchangeably.

[0035] The present disclosure will now be described in detail with reference to the drawings. However, this is merely exemplary, and the present disclosure is not limited to the specific embodiments described as exemplary.

[0036] Fig. 1 is a perspective view of a battery module according to an embodiment of the present disclosure and Fig. 2 is a perspective exploded view of a battery module according to an embodiment of the present disclosure

[0037] With reference to Fig. 1 and Fig. 2, a battery module 10 to which a sealing pad 500 of the present disclosure is attached will first be described.

[0038] The battery module 10 may include a cell assembly 100 that includes a plurality of battery cells 110, a housing 200 having a receiving space that receives the battery cells, a bus bar assembly 300 that is electrically connected to the battery cells 110, a circuit portion 410 that detects various electrical signals of the battery cells 110, and a connector 450 that is connected to the circuit portion 410 and connected to the exterior.

[0039] The plurality of battery cells 110 housed in the battery module 10 can be stacked in one direction (X-axis direction) to form at least a portion of the cell assembly 100. Each battery cell 110 can output or store electrical energy. In the cell assembly 100, the battery cells 110 can be electrically connected to each other by the bus bar assembly 300.

[0040] The plurality of battery cells 110 may be configured to convert chemical energy into electrical energy to supply power to an external circuit, or to receive energy from the outside and convert electrical energy into chemical energy to store electricity. For example, the battery cell 110 may be configured as a nickel metal hydride (Ni-MH) battery or a lithium ion (Li-ion) battery capable of being charged with or discharged from electricity.

[0041] The plurality of battery cells 110 may be provided by accommodating an electrode assembly (not shown) formed by stacking a cathode plate and an anode plate. The electrode assembly may be configured in a form in which the cathode plate and the anode plate are stacked with a separator interposed therebetween in a state where wide surfaces thereof face each other. The separator may be configured to prevent electrical short circuiting between the cathode plate and the anode plate and to allow ion flow. For example, the separator may include a porous polymer film or a porous nonwoven fabric.

[0042] In addition, the electrode assembly may have a jelly roll shape formed by winding in a predetermined direction and thus may be housed in a case in various types such as a stack type, a zigzag folding type, a stack folding type, and the like.

[0043] The plurality of battery cells 110 may be secondary batteries of a bag-like type, a prismatic type, or a cylindrical type depending on the structure of the case.

[0044] The battery cell 110 of the present disclosure may include a housing 111 that houses the electrode assembly and a lead tab 112 that protrudes from at least one side of the housing and is electrically connected to a bus bar 310 described below.

[0045] In addition, the cell assembly 100 may further include a protective pad (not shown). The protective pad may cause damage to other battery cells due to the occurrence of an event (e.g., a situation in which high-temperature gas or flame is generated, or a battery cell expands abnormally). For example, a protective member may include a material capable of blocking heat to prevent heat from being transferred between adjacent battery cells 110. Alternatively, the protective member may include a material capable of exerting surface pressure on the battery cell 110 and may function to suppress expansion of the battery cell 110.

[0046] The plurality of battery cells 110 included in the cell assembly 100 may be electrically connected to each other by the busbar assembly 300 via the lead tab 112. At least a portion of the busbar assembly 300 may face the cell assembly 100 in a direction perpendicular to a cell stacking direction (Y-axis direction).

[0047] The housing 200 provides an interior space in which one or more cell assemblies 100 may be housed. The housing 200 may be formed from a material with a predetermined degree of rigidity to protect the cell assemblies 100 and other electrical components housed within the interior space from external impacts. For example, the housing 200 may include a metal material, such as aluminum.

[0048] The housing 200 may include a first cover 210, a second cover 220, and an end plate 230 covering a side portion, which are arranged to face the cell assemblies 100 in a height direction (Z-axis direction).

[0049] The first cover 210 may be disposed above the cell assemblies 100 to cover the cell assemblies 100. The first cover 210 may include a terminal hole 215 through which a terminal portion 315 described below is exposed, and a connector hole 217 through which a connector 350 is exposed. Here, the terminal hole 215 and the connector hole are collectively referred to as a "through hole." In other words, the through hole collectively refers to a hole formed in the housing 200, including the terminal hole 215 and the connector hole 217.

[0050] Since the first cover 210 is arranged above the cell assembly 100, the first cover 210 may also be referred to as a “top cover”.

[0051] The second cover 220 may be disposed in a lower portion of the cell assembly 100 to support the cell assembly 100. The second cover 220 may include a lower plate 221 facing an upper cover 210 and supporting the lower portion of the cell assembly 100, and a side plate 222 disposed at a side portion of the cell assembly 100, e.g., in a longitudinal direction (Y-axis direction) of the cell assembly 100.

[0052] Since the second cover 220 is arranged below the cell assembly 100, the second cover 220 may also be referred to as a “bottom cover”.

[0053] The end plate 230 may cover a portion not covered by the upper cover 210 and the lower cover 220. For example, the end plates 230 may be provided in pairs and may be arranged to cover both side surfaces of the cell assembly 100 in a stacking direction (X-axis direction).

[0054] However, the structure of the housing 200 is not limited thereto and may have any shape as long as the housing 200 has an internal space in which at least one cell assembly 100 can be accommodated. For example, the housing 200 may be formed integrally with the top cover 210 and may be configured as an integral monoframe in which both side surfaces are open.

[0055] A heat dissipation member (not shown) may be disposed between the cell assembly 100 and the casing 200. The heat dissipation member (not shown) may be provided such that one surface thereof is in contact with the cell assembly 100 and the other surface opposite the one surface is in contact with the casing 200. The heat dissipation member (not shown) may be provided as a thermal adhesive. The heat dissipation member (not shown) may fill a space between the cell assembly 100 and the casing 200 to enable more active heat transfer by conduction. Accordingly, the heat dissipation efficiency of the battery module 10 can be increased.

[0056] The busbar assembly 300 may include a busbar 310 that electrically connects one battery cell 110 to another battery cell 110 and a support frame 320 that supports the busbar 310.

[0057] Some of the bus bars 310 of the bus bar assembly 300 may include a terminal portion 315 that may be electrically connected to a power source external to the battery module 10. The terminal portion 315 may be exposed to the exterior of the battery module 10 through the terminal hole 215 formed in the housing 200.

[0058] The busbar 310 may be coupled to a support frame 320. The support frame 320 may be formed from an electrically insulating material to prevent an inadvertent short circuit from occurring between the plurality of busbars 310. The support frame 320 may face at least one side of the cell assembly 100.

[0059] The circuit section 410 may be connected to the cell assembly 100 to detect an operating status, an environmental status, humidity, a current pressure, and the like of the battery cells 110. The connector 450 may connect the circuit section 410 and the exterior of the battery module 10, for example, a battery management system (BMS), thereby transmitting and receiving information about the battery cell 110 to and from the exterior. The connector 450 may be exposed to the exterior of the battery module 10 through a connector hole 217 formed in the housing 200.

[0060] Additionally, the battery module of the present disclosure may include an insulating cover 340 formed of an electrically insulating material and disposed between the bus bar assembly 300 and the housing 200, specifically the side plate 222, to electrically protect the battery cell 110.

[0061] For example, the insulating cover 340 may be disposed between the busbar assembly 300 and the housing 200 to face the busbar assembly 300. The insulating cover 340 may include an insulating material and thus may block an electrical connection between the busbar assembly 300 and the housing 200. For example, the insulating cover 340 may be formed from a plastic injection-molded product including polypropylene or modified polyphenylene oxide (MPPO). However, the material of the insulating cover 340 is not limited thereto. By disposing the insulating cover 340, an electrical short circuit between the cell assembly 100 and the housing 200 or between the busbar 310 and the housing 200 can be prevented.

[0062] The bus bar 310 may be formed of a conductive material and serves to electrically connect a plurality of battery cells 110 to each other. The bus bar 310 may be electrically connected to the lead tab 112 of the battery cell 110. Various welding methods, including laser welding, may be used to connect the bus bar 310 and the lead tab 112. However, the connection method is not limited to welding, and any connection method that can electrically connect two metallic materials may be used.

[0063] Fig. 3 is an enlarged view of part A of Fig. 2, Fig. 4 is an enlarged view of part B of Fig. 3 and Fig. 5 is a cross-sectional view along a Y-axis direction in Fig. 3.

[0064] According to one embodiment of the present disclosure, a fluid may be accommodated in the accommodation space of the housing 200. The fluid referred to in the present disclosure may be an insulating cooling fluid for cooling the battery cell 110 in the accommodation space of the housing 200 or a liquid foam that prevents thermal runaway of the battery cells within the accommodation space or prevents or extinguishes fire occurring in the accommodation space. In this case, in order to prevent the fluid from leaking through a hole formed in the housing 200 (e.g., a terminal hole 215 or a connector hole 217), the sealing pad 500 may be arranged in a vicinity thereof (see Fig. 3). The sealing pad 500 may, for example, include a material such as EPDM formed from a rubber material.

[0065] According to one embodiment, the sealing pad 500 may be attached to the housing 200 and arranged in the receiving space.

[0066] Meanwhile, the "cooling fluid" in the present disclosure refers to a fluid that acts as an electrical insulator, and may be, for example, an insulating oil with a non-conductive oil as the main component. However, the cooling fluid of the present disclosure is not limited thereto, and any fluid having the property capable of cooling the battery cell 110 by exchanging heat with the battery cell 110 may be included therein.

[0067] In addition, the “liquid foam” in the present disclosure means that a foam material for preventing an event such as thermal runaway of the battery cell 110 or for preventing or extinguishing fire occurring in the battery cell 110 includes a solvent.

[0068] In addition, the present disclosure can be applied even if the housing 200 does not contain a fluid. In other words, the scope of the present disclosure is not limited depending on the presence or absence of the fluid, and even if the sealing pad 500 is disposed in a bent portion c of the housing 200, this should be considered to be within the scope of the present disclosure.

[0069] Meanwhile, the sealing pad 500 may be attached to the housing 200 with an adhesive or the like, but there may be a problem that the adhesive strength is reduced due to the shape of the housing 200 (e.g., a curved portion).

[0070] With further reference to Fig. 2, there is no bent portion of the housing 200 in a vicinity of the connector hole 217, but the terminal hole 215 may structurally have a bent portion formed in the vicinity thereof (c, see Fig. 3). That is, the terminal hole 215 may be formed to at least partially penetrate the bent portion c. The bent portion c may be formed by bending a shell of the housing 200 with a predetermined curvature.

[0071] That is, the housing 200 may include a bent portion c having a predetermined curvature. The bent portion c may be convex toward the internal accommodating space of the housing 200 or the cell assembly 100.

[0072] In this case, a sealing pad 500 (see Fig. 3) disposed in the vicinity of the terminal hole 215 may be disposed to coincide with the bent portion c. In this case, the sealing pad 500 may experience a phenomenon in which stress is concentrated in a portion thereof that coincides with the bent portion c, and the adhesive strength of the portion is weakened, causing the sealing pad 500 to be lifted and detached in a portion that overlaps the bent portion c.

[0073] Meanwhile, in the present disclosure, "conforming to the bent portion c" may mean that at least a portion thereof is arranged to overlap the bent portion c, arranged to face the bent portion c, or arranged to be in contact with the bent portion c. In other words, this may mean that a shape of the sealing pad 500 is convexly bent so that at least a portion thereof conforms to the bent portion c through the bent portion c.

[0074] When the sealing pad 500 is peeled off, a fluid, such as a liquid foam, may leak through the connection hole 215, so it may be critical to improve the adhesive strength of the sealing pad 500 regardless of the bending shape of the housing 200.

[0075] That is, the sealing pad 500 of the present disclosure may be provided to prevent the fluid, such as a liquid foam, from leaking through the through-hole regardless of the shape of the bent portion c.

[0076] In this case, with reference to Fig. 3 to Fig. 5, the present disclosure may include the sealing pad 500 arranged to overlap the bent portion c of the housing 200, but the sealing pad 500 may include a stress-relieving portion 530 provided to at least partially coincide with the bent portion c.

[0077] Fig. 3 is an inverted view of part A in Fig. 2. This means that Fig. 3 is a view of part A from the receiving space of the housing 200.

[0078] The sealing pad 500 of the present disclosure may include a pad body 510 arranged to at least partially coincide with the bent portion c, and a stress-relieving portion 530 arranged in a position corresponding to the bent portion c in the pad body 510 to disperse stress in a portion thereof corresponding to the bent portion c. In other words, the sealing pad 500 may include the pad body 510 arranged to at least partially contact the bent portion c, and the stress-relieving portion 530 provided in the pad body 510 to face the bent portion c and disperse the stress exerted on the pad body 510 by the bent portion c.

[0079] The sealing pad 500 may be attached to the housing 200 to surround the terminal hole 215. For example, the sealing pad 500 may be attached to an inner surface (a surface facing the receiving space) of the top cover 210 in which the terminal hole 215 is formed. However, the present disclosure is not limited thereto and may also include the sealing pad 500 attached to the housing 200 to surround the connector hole 217.

[0080] According to one embodiment, the top cover 210 may include a first plate 211 coupled to the bottom cover 220, a second plate 212 extending from the first plate, and a third plate 213 extending from the second plate 212 to cover the cell assembly 100.

[0081] According to one embodiment, a bent portion c may be formed between the first plate 211 and the second plate 212 or between the second plate 212 and the third plate 213.

[0082] The bent portion c may refer to a portion bent between at least two of the first plate 211, the second plate 212, or the third plate 213.

[0083] In Fig. 3, two portions in which the plates are bent are provided between the first plate 211 and the second plate 212 and between the second plate 212 and the third plate 213, but of these, in this specification, a portion bent between the first plate 211 and the second plate 212 is referred to as “bent portion c” and will be described.

[0084] With reference to Fig. 4, the sealing pad 500 may include a pad body 510 coupled or attached to the housing 200 to conform to the bent portion c, and a stress-relieving portion 530 arranged to conform to the bent portion c in the pad body 510.

[0085] Meanwhile, the meaning of "conforming to the bent portion c" in this specification not only means directly contacting the bent portion c, but may also mean being arranged to overlap the bent portion c in a predetermined direction (the Y-axis direction or the Z-axis direction in the drawing). That is, this may mean that at least a portion of the sealing pad 500 with a radius of curvature conforming to the bent portion c is at least partially convexly bent by the bent portion c.

[0086] Here, the "portion where the sealing pad 500 overlaps the bent portion c" may mean "at least a portion of the pad body 510 that covers the bent portion c." The stress-relieving portion 530 may be disposed in the "at least a portion of the pad body 510 that covers the bent portion c."

[0087] The pad body 510 may include a first surface (not shown, a surface at least partially contacting the housing 200) facing and in contact with the housing 200, and a second surface (not shown) opposite the first surface and facing the receiving space. The stress-relieving portion 530 may be formed on the second surface.

[0088] In this case, the first surface of the pad body 510 may be arranged to at least partially contact the bent portion c. In addition, the stress-relieving portion 530 may include at least one notched groove 531 formed by deepening at least a portion thereof in a direction oriented from the second surface toward the first surface (thickness direction of the pad body 510). In this case, the at least one notched groove 531 may be arranged in the pad body 510 to face the bent portion c to alleviate the stress concentration caused by the bent portion c.

[0089] Meanwhile, as shown in the drawing, the bent portion c may be provided in a shape that is convexly bent toward the receiving space or the at least one notch groove 531. Accordingly, the pad body 510 may also be arranged in a shape in which at least a portion thereof has a radius of curvature that coincides with the bent portion toward the receiving space and at least a portion thereof is convexly bent.

[0090] With reference to Fig. 5, the stress-relieving portion 530 can prevent the pad body 510 from peeling off from one side (a side near a -Y axis) of the bent portion c by concentrating the stress in the vicinity of the bent portion c. The stress-relieving portion 530 is provided to disperse the stress concentrated on a portion of the pad body 510 overlapping the bent portion c.

[0091] For example, the stress-relieving portion 530 may include one or more notched grooves 531. The notched grooves 531 may be formed as recessed grooves along a thickness of the pad body 510.

[0092] For example, the notched groove 531 is schematically drawn with bold lines in the drawing for ease of understanding, but the notched groove 531 of the present disclosure may be formed as a groove recessed in a thickness direction of the pad body 510 or as a sheath shape cut in a thickness direction. Stress is concentrated in a portion where the pad body 510 and the bent portion c overlap each other, so that a surface of the pad body 510 (a surface in a -Z axis direction) is opened by the bent portion c. However, since the stress concentrated on the pad body 510 is dispersed by the notched groove 531, the pad body 510 can be prevented from being lifted off the housing 200.

[0093] With reference to Fig. 6 and in advance on Fig. 7, the notched groove 531 may be formed in a pattern in a predetermined direction.

[0094] In addition, the stress-relieving portion 530 may be formed on a surface of the pad body 510 that is bent and stretched by the bent portion c. Specifically, with reference to Fig. 5, on both surfaces of the pad body 510 in the thickness direction (Z-axis direction), a surface (a surface located in the -Z-axis direction) may be provided to be opened by the bent portion c. Accordingly, the notched groove 531 of the stress-relieving portion 530 may be formed by being recessed in one surface.

[0095] In other words, an inner surface of the housing 200 may be formed convexly toward the receiving space by the bent portion c, and an outer surface opposite thereto may be formed concavely. Additionally, the stress-relieving portion 530 may be arranged to overlap the convexly formed portion.

[0096] Meanwhile, the stress-relieving portion 530 of the present disclosure is not limited to this. For example, the stress-relieving portion 530 may also be disposed in a bent portion between the second plate 212 and the third plate 213. Since the stress in this portion is concentrated on a surface (a surface in a +Z-axis direction in the drawing) in contact with the top cover 210, the stress-relieving portion 530 may be disposed on a surface (a surface in the +Z-axis direction) in contact with the top cover 210 on both side surfaces of the pad body 510 in the thickness direction (Z-axis direction).

[0097] Fig. 6 is a view of a sealing pad according to an embodiment, and Fig. 7 is a view of a sealing pad according to another embodiment. Referring to Fig. 6 and Fig. 7, the stress-relieving portion 530 may be formed in various patterns formed by a plurality of notched grooves 531.

[0098] With reference to Fig. 6, the stress-relieving portion 530 may be formed in a pattern in which a plurality of notched grooves 531 are arranged in a single row. The number of notched grooves 531 in the drawing is three, but is not limited thereto.

[0099] In addition, a vertical distance d between adjacent notch grooves 531 and a distance between the notch grooves 531 and an end of the pad body 510 in an extending direction of the notch grooves 531 (for example, hereinafter referred to as “end distance”) may vary depending on the shape, size, radius of curvature, and the like of the bent portion c.

[0100] For example, according to one embodiment, the vertical distance d between the notch grooves 531 may be 1 mm to 3 mm, and an end distance e may be 1.25 mm to 3.75 mm.

[0101] In another example, the vertical distance d between the notches 531 and the end distance e may be 1:1.25 (d = 1.25e).

[0102] With reference to Fig. 7, the stress-relieving portion 530 may form a predetermined pattern with a plurality of notched grooves 531 in a plurality of rows. For example, a first notched groove group and a second notched groove group in which the plurality of notched grooves 531 are offset from each other may be arranged in the stress-relieving portion 530.

[0103] In addition, a distance d between adjacent notched grooves 531, an extension length m of the notched grooves 531, and a horizontal distance n between the notched grooves 531 may vary according to the extension direction of the notched grooves 531 depending on the shape, size, radius of curvature, and the like of the bent portion c.

[0104] For example, the vertical distance d between the notches 531 can be 1.25 mm to 3.75 mm, the extension length m of the notches 531 can be 0.5 mm to 1.5 m, and the horizontal distance n between the notches 531 can be 0.5 mm to 1.5 m. The extension length m of the notches 531 can be equal to or greater than the horizontal distance n between the notches 531.

[0105] As another example, the extension length m of the notch grooves 531 and the vertical distance d between the notch grooves 531 may be 1:2.5 (d = 2.5 m), and the horizontal distance n of the notch grooves 531 and the vertical distance d between the notch grooves 531 may be 1:2.5 (d = 2.5n).

[0106] The present disclosure also relates to the following aspects. Aspect 1) Battery module comprising: a plurality of battery cells; a casing that accommodates the plurality of battery cells in an internal accommodation space and includes a bent portion bent with a predetermined curvature; and a sealing pad attached to the casing to at least partially contact the bent portion, the sealing pad including: a pad body that at least partially coincides with the bent portion; and a stress-relieving portion that is disposed in a portion of the pad body that coincides with the bent portion and disperses a stress in a portion thereof that coincides with the bent portion. Aspect 2) In aspect 1, wherein the housing includes a terminal hole through which the receiving space communicates with an exterior of the housing, and the sealing pad is arranged to surround at least a portion of a vicinity of the terminal hole. Aspect 3) In aspect 1 or 2, wherein the housing includes a terminal hole through which the receiving space communicates with an exterior of the housing, and the bent portion is formed in the vicinity of the terminal hole. Aspect 4) In any one of aspects 1 to 3, wherein the bent portion is formed convexly toward the receiving space. Aspect 5) In any one of aspects 1 to 4, wherein the pad body includes a first surface facing and in contact with the housing and a second surface opposite to the first surface and facing the receiving space, and the stress-relieving portion is formed on the second surface. Aspect 6) In aspect 5, wherein the first surface of the pad body is arranged to be at least partially in contact with the bent portion. Aspect 7) In aspect 5 or 6, wherein the stress-relieving portion includes at least one notch groove formed by deepening at least a portion thereof in a direction oriented from the second surface toward the first surface. Aspect 8) In aspect 7, wherein the at least one notch groove is arranged to face the bent portion. Aspect 9) In aspect 7 or 8, wherein the bent portion is formed convexly in a direction oriented toward the at least one notch groove. Aspect 10) In any one of aspects 1 to 9, wherein the stress-relieving portion includes a plurality of notched grooves arranged in a predetermined pattern. Aspect 11) In aspect 10, wherein the plurality of serrations form a predetermined pattern arranged in one or more rows in a predetermined direction. Aspect 12) In aspect 2 or 3, further comprising: a bus bar assembly electrically connected to the plurality of battery cells; and a terminal portion electrically connected to the bus bar assembly and exposed to the outside of the housing through the terminal hole, wherein the sealing pad is arranged to at least partially surround the terminal portion in the vicinity of the terminal hole. Aspect 13) In aspect 2 or 3, wherein the housing further includes: a lower cover supporting the plurality of battery cells; and an upper cover arranged to face the lower cover, wherein the terminal hole is arranged in the upper cover. Aspect 14) In aspect 2 or 3, wherein the receiving space is provided to allow a fluid to be injected, and the sealing pad is provided to prevent the fluid from leaking through the port hole. Aspect 15) In aspect 14, wherein the fluid includes a liquid foam that prevents or extinguishes fire, and the sealing pad is provided to prevent the liquid foam injected into the receiving space from leaking out. Aspect 16) In any one of aspects 1 to 4, wherein the pad body is arranged such that at least a portion of the pad body is in contact with the bent portion, and the stress-relieving portion is arranged to face the bent portion.

[0107] Disclosed is a battery module that may include: a plurality of battery cells; a casing that accommodates the plurality of battery cells in an internal accommodation space and includes a bent portion bent with a predetermined curvature; and a sealing pad attached to the casing to at least partially contact the bent portion, the sealing pad including: a pad body that at least partially coincides with the bent portion; and a stress-relieving portion that is disposed in a portion of the pad body that coincides with the bent portion and disperses a stress in a portion thereof that coincides with the bent portion.

Claims

[1] Battery module (10), comprising: a plurality of battery cells (110); a housing (200) accommodating the plurality of battery cells (110) in an internal accommodating space and including a bent portion (c) bent with a predetermined curvature; and a sealing pad (500) attached to the housing (200) to be at least partially in contact with the bent portion, wherein the sealing pad (500) includes: a pad body (510) which at least partially coincides with the bent portion (c); and a stress-relieving portion (530) disposed in a portion (410) of the pad body (510) corresponding to the bent portion and dispersing a stress in a portion (410) thereof corresponding to the bent portion (c). [2] Battery module (10) according to claim 1, wherein the housing (200) includes a connection hole (215) through which the receiving space communicates with an exterior of the housing (200), and the sealing pad (500) is arranged to surround at least a portion (410) of a surrounding of the connection hole (215). [3] Battery module (10) according to claim 1 or 2, wherein the housing (200) includes a connection hole (215) through which the receiving space communicates with an exterior of the housing (200), and the bent portion (c) is formed in the vicinity of the terminal hole (215). [4] Battery module (10) according to one of claims 1 to 3, wherein the bent portion (c) is convex towards the receiving space. [5] Battery module (10) according to one of claims 1 to 4, wherein the pad body (510) includes a first surface facing and in contact with the housing (200) and a second surface opposite the first surface and facing the receiving space, and the stress-relieving portion (530) is formed on the second surface. [6] The battery module (10) according to claim 5, wherein the first surface of the pad body (510) is arranged to be at least partially in contact with the bent portion (c). [7] The battery module (10) according to claim 5 or 6, wherein the stress-relieving portion (530) includes at least one notched groove (531) formed by deepening at least a portion (410) thereof in a direction oriented from the second surface toward the first surface. [8] Battery module (10) according to claim 7, wherein the at least one notch groove (531) is arranged to face the bent portion (c). [9] Battery module (10) according to claim 7 or 8, wherein the bent portion (c) is convex in a direction oriented toward the at least one notched groove (531). [10] The battery module (10) according to any one of claims 1 to 9, wherein the stress-relieving portion (530) includes a plurality of notched grooves (531) arranged in a predetermined pattern. [11] The battery module (10) according to claim 10, wherein the plurality of notched grooves (531) form a predetermined pattern arranged in one or more rows in a predetermined direction. [12] Battery module (10) according to claim 2 or 3, further comprising: a busbar assembly (300) electrically connected to the plurality of battery cells (110); and a terminal portion (315) electrically connected to the busbar assembly (300) and exposed to the exterior of the housing (200) through the terminal hole (215), wherein the sealing pad (500) is arranged to at least partially surround the connection portion (315) in the vicinity of the connection hole (215). [13] Battery module (10) according to claim 2 or 3, wherein the housing (200) further includes: a lower cover (220) supporting the plurality of battery cells (110); and an upper cover (210) arranged to face the lower cover (220), wherein the connection hole (215) is arranged in the top cover (210). [14] Battery module (10) according to claim 2 or 3, wherein the receiving space is provided to allow a fluid to be injected, and the sealing pad (500) is provided to prevent the fluid from leaking through the connection hole (215). [15] Battery module (10) according to claim 14, wherein the fluid contains a liquid foam that prevents or extinguishes fire, and the sealing pad (500) is provided to prevent the liquid foam injected into the receiving space from leaking out. [16] Battery module (10) according to one of claims 1 to 4, wherein the pad body (510) is arranged such that at least a portion (410) of the pad body (510) is in contact with the bent portion (c), and the stress-relieving portion (530) is arranged to face the bent portion (c).

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