Battery cell with vent cover and battery module containing the same

Abstract

Battery cell (10) comprising: a casing (110) accommodating an electrode assembly (120) in a receiving chamber; a cap plate (130) coupled to at least one side of the casing (110); a vent (133) provided in the casing (110) or the cap plate (130); and a vent cover (200) arranged to cover the vent (133) and provided to be opened by a pressure acting from the receiving chamber to the outside of the casing (110), wherein the vent cover (200) comprises: a vent film (230) provided to be opened by a predetermined pressure level, comprising a first surface facing the vent (133) and a second surface opposite the first surface; and a vent cap (210) with a support section (213) that supports the first surface of the vent film (230).

Description

TECHNICAL FIELDThe present disclosure relates to a battery cell having a vent cover and a battery module including the same.BACKGROUNDA secondary battery has convenience, unlike a primary battery, because it can be charged and discharged, and draws much attention as a power source for various mobile devices and electric vehicles.Such a secondary battery may include a battery cell in which an electrode assembly formed by stacking a cathode plate, an anode plate, and a separator or by winding them in a roll shape together with an electrolyte is housed inside a case. A plurality of battery cells may be stacked in a predetermined direction and housed in a battery module or battery pack.Some types of secondary batteries may include a vent connecting the interior of the casing and the exterior of the casing for communication therebetween to allow gas generated within the casing to be discharged to the exterior of the casing when an event such as thermal runaway has occurred. However, there may be a problem that flames or gas flowing from the outside of the shroud through the vent may also flow into the inside of the shroud.The above description is provided to help understand the technical background of the present disclosure, and should not be construed as reducing, limiting, or limiting the technical spirit of the present disclosure. In addition, the contents described or proposed in the above description do not necessarily refer to the related art, and some may include contents that do not fall within the related art.SUMMARYAn aspect of the present disclosure may provide a battery cell that can emit flames, gas, or the like inside a storage space to the outside of a case when an event has occurred, but can prevent flames, gas, or the like from flowing from the outside of the case into the storage space.An aspect of the present disclosure may provide a battery module that can emit flames, gas, or the like inside the accommodation space to the outside of a case when an event has occurred, but can prevent flames or gas generated inside an adjacent battery cell from flowing in.In addition, a battery cell and a battery module including the same of the present disclosure can be widely applied to fields of green technology such as electric vehicles, battery charging stations, and solar power generation and wind power generation using batteries. In addition, the battery cell and the battery module of the present disclosure may be used in eco-friendly electric vehicles, hybrid vehicles, or the like to prevent climate conversion by suppressing air pollution and greenhouse gas emissions.According to an aspect of the present disclosure, a battery cell may include: a case that accommodates an electrode assembly in a storage space; a cap plate coupled to at least one side of the case; a vent provided in the case or the cap plate; and a vent cover disposed to cover the vent and provided to be opened by a pressure acting from the storage space to the outside of the case, wherein the vent cover includes a vent film provided to be opened by a predetermined pressure level and includes a first surface facing the vent and a second surface opposite the first surface; and a vent cap having a support portion that supports the first surface of the vent film.Additionally, according to an embodiment, the venting film may include a venting line formed on at least one of the first surface or the second surface.In addition, according to an embodiment, the vent film may be disposed to face the vent in a first direction, and the support portion may be disposed to be associated with the vent line, so that at least a portion of the support portion may be provided to overlap the vent line in the first direction.Additionally, according to an embodiment, the vent line may be formed by being partially recessed from the second surface.In addition, according to an embodiment, the vent may be provided to be opened by a predetermined pressure level and is provided to connect the accommodation space and the exterior of the casing for communication therebetween.Additionally, according to an embodiment, the vent may include a notch groove formed by being at least partially recessed in a thickness direction.In addition, according to an embodiment, the vent cover may be provided to be opened when a pressure inside the accommodation space becomes larger than a pressure outside the jacket by a predetermined margin to be opened by a force from the accommodation space to the outside of the jacket.In addition, according to an embodiment, the vent cover further includes a vent space formed between the vent film and the vent, the vent may be provided to be opened by a pressure difference between the accommodation space and the vent space, and the vent film may be provided to be opened to the outside of the casing when the vent is opened.According to an aspect of the present disclosure, a battery cell may include: a case that accommodates an electrode assembly in a storage space; a cap plate coupled to at least one side of the case; and a vent cover provided in the cap plate or the case and provided to be opened in a direction from the storage space to the outside of the case, the vent cover including: a vent film provided to be opened by a predetermined pressure level, and a vent line formed on at least one of a first surface facing the storage space and a second surface opposite the first surface in a first direction; and a vent cap having a support portion that supports the first surface of the vent film, wherein at least a portion of the support portion is provided so as to overlap the vent line in the first direction.According to an aspect of the present disclosure, a battery module may include: a plurality of battery cells; and a module case accommodating the plurality of battery cells, at least one of the plurality of battery cells including: a case accommodating an electrode assembly in an accommodation space; a cap plate coupled to at least one side of the case; a vent provided in the case or the cap plate; and a vent cover disposed to cover the vent and provided to be opened by a pressure acting from the accommodation space to the outside of the case, the vent cover including: a vent film provided to be opened by a predetermined pressure level and having a first surface facing the vent and a second surface opposing the first surface; and a vent cap having a support portion that supports the first surface of the vent film.As described above, the solution according to the present disclosure has been described, but this is exemplary, and it should be understood that other non-mentioned configurations are also included in the present disclosure.BRIEF DESCRIPTION OF THE DRAWINGSThe above and other aspects, features and other advantages of the present disclosure will become more apparent from the following detailed description taken in conjunction with the accompanying drawings, in which: FIG. 1 is a perspective view of a battery cell according to an embodiment of the present disclosure. FIG. 2 is a schematic internal cross-sectional view taken along line I-I' of FIG. 1. FIG. 3 is an exploded view of a vent cap. FIG. 4 is an enlarged view of A in FIG. 2. FIG. 5 is a diagram exemplarily illustrating that a vent cover is opened to the outside of the shroud. FIG. 6 is a diagram exemplarily illustrating that reverse inflow of gas flowing from the outside of the shroud is prevented. FIG. 7 is a battery module according to an embodiment of the present disclosure. FIG. 8 is a diagram illustrating, by way of example, that an event has occurred in a battery cell of the battery module.DETAILED DESCRIPTIONThe same reference numerals or symbols described in each drawing represent parts or components that perform substantially the same functions. For convenience in description and understanding, the same reference numerals or symbols may be used in different embodiments.In the following description, unless the context clearly dictates otherwise, singular terms include plural terms. It should be understood that terms such as "include" or "comprise" 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 ability of one or more other features, numbers, steps, operations, components, parts, or combinations thereof to be present or added.In addition, in the following description, expressions such as the upper side, the upper portion, the lower side, the side surface, the front side, the rear side, etc. are expressed based on the direction illustrated in the drawings, and can be expressed changed when the direction of the object is changed.In addition, terms including ordinal numbers such as "first", "second", or the like may be used to distinguish between components in the following description and claims. These ordinal numbers are used to distinguish between identical or similar components, and the meaning of the terms should not be limited due to the use of these ordinal numbers. For example, the components associated with these ordinal numbers should not be interpreted in an order of use or arrangement restricted by their numbers. If necessary, corresponding ordinal numbers may be used interchangeably.Hereinafter, the present disclosure will be described in detail with reference to the drawings.FIG. 1 is a perspective view of a battery cell according to an embodiment of the present disclosure, and FIG. 2 is a schematic internal cross-sectional view taken along line I-I' of FIG. 1.Referring to FIGS. 1 and 2, a battery cell 10 of the present disclosure may include a case 110 that houses an electrode assembly 120 in a housing space S, a cap plate 130 coupled to at least one side of the case 110, a vent 133 provided in the case 110 or the cap plate 130, and a vent cover 200 that is disposed to cover the vent 133 but is provided to be opened by a pressure acting from the housing space S to the outside of the case 110. Here, the vent cover 200 may include a vent film 230 provided to be opened by a predetermined pressure level and including a first surface facing the vent 133 and a second surface opposing the first surface, and a vent cap 210 having a support portion supporting the first surface of the vent film 230.The case 110 may provide a storage space S in which an electrode assembly 120 to be described later may be stored. In the drawing, the case 110 is illustrated as an approximately rectangular shape, but this is only an example, and the case may be changed to various shapes as long as it has a structure in which a storage space S for storing the electrode assembly 120 is formed.In addition, a cap plate 130 to be described later may be coupled to an opening (not shown) of the case 110 to seal the accommodation space S.A material of the case 110 may be appropriately selected in consideration of thermal and electrical conductivity, rigidity corresponding to swelling of the electrode assembly 120, workability, manufacturing cost, or the like. For example, the casing 110 may be formed of a metallic material including aluminum, an aluminum alloy, or the like.The electrode assembly 120 may be disposed in the accommodation space S of the case 110. The electrode assembly 120 may include a cathode material 121. The cathode material 121 may include a cathode current collector and a cathode active material. In some embodiments, the cathode current collector may include aluminum, an aluminum alloy, or the like, and the cathode active material may include lithium cobalt oxide, lithium manganese oxide, lithium nickel oxide, lithium iron phosphate, or the like. The cathode active material may be deposited on a surface of the cathode current collector. Portions of the cathode current collector that are not coated with the cathode active material may function as cathode tabs 120 a. In some embodiments, the cathode tab 120 amay be provided in the plurality, and some or all of the plurality of cathode tabs 120 amay be connected to each other.The electrode assembly 120 may include an anode material 122. The anode material 122 may include an anode current collector and an anode active material. In some embodiments, the anode current collector may include copper, a copper alloy, nickel, a nickel alloy, or the like, and the anode active material may include carbon, silicon, or the like. The anode active material may be coated on a surface of the anode current collector. Portions of the anode current collector that are not coated with an anode active material may function as anode electrode tab 120 b. In some embodiments, the anode tab 120 bmay be provided in the plurality, and some or all of the plurality of anode tabs 120 bmay be connected to each other.The electrode assembly 120 may include a separator 123. The separator 123 may be disposed between a cathode material 121 and an anode material 122. The separator 123 may function to provide a passage for the movement of ions while physically contacting the cathode material 121 and the anode material 122. For example, the separator 123 may include a porous polymer film or a porous substrate. In some embodiments, the separator 123 may be formed of a polymeric material including polyethylene, polypropylene, or the like. In addition, the separator 123 may include a dry and wet separator. In some embodiments, the separator 123 may include a coating layer including a ceramic coating layer or the like.The electrode assembly 120 may be formed by arranging the above-described components in a method such as winding, stacking, or the like. For example, the electrode assembly 120 may be formed in a structure in which the cathode material 121, the anode material 122, and the separator 123 are wound around an axis in a longitudinal direction or a transverse direction. Alternatively, the electrode assembly 120 may be formed as a structure in which the above-described winding structure is compressed in a direction approximately perpendicular to a winding axis. The winding structure described above may be referred to in the art as a "biscut roll".As another example, the electrode assembly 120 may be formed in a structure in which a cathode material 121, an anode material 122, and a separator 123 are sequentially stacked in a vertical direction (e.g., in a thickness direction or height direction of the electrode assembly). In some cases, the separator 123 may be formed in the stacked structure as a stacked structure in which a plurality of unit separators 123 continuous in the longitudinal direction are sequentially folded corresponding to the stack of the cathode material 121 and the anode material 122. The stacked structure described above may be referred to in the art as "stacking and folding", "z-folding", or the like. However, in this embodiment, the arrangement of each component of the electrode assembly 120 is not particularly limited. The electrode assembly 120 may include arrangements other than the above example arrangements.In some embodiments, the electrode assembly 120 may be formed by combining a plurality of unit associations. For example, the electrode assembly 120 may include unit composites wound in a wound biscuite roll manner, and two or more of the unit composites may be combined to form an electrode assembly 120. In the present embodiment, the electrode assembly 120 is composed of two unit biscuite rollers. As another example, the electrode assembly 120 may include a unit package wound in a stack-fold manner, and two or more of the unit packages may be combined to form an electrode assembly 120.The electrode assembly 120 may be accommodated together with an electrolyte in an accommodation space S of the case 110. In some embodiments, the electrolyte may be formed from an organic solvent containing a lithium salt. For example, the lithium salt may include lithium hexafluorophosphate (LiPF6), lithium tetrafluoroborate (LiB4), or the like in a liquid or gel state, and the organic solvent may include cyclic carbonates such as ethylene carbonate (EC), propylene carbonate (PC), or the like, and linear carbonates such as diethyl carbonate (DEC), dimethyl carbonate (DMC), ethylmethyl carbonate (EMC), or the like.In some other embodiments, the electrolyte may be omitted or replaced. For example, when an inorganic solid electrolyte is used, the liquid or gel electrolyte may be omitted.In addition, the structure of the electrode assembly 120 illustrated in the present disclosure is exemplary. In the present disclosure, an electrode assembly 120 including a cathode tab 120 aand an anode tab 120 barranged in parallel from one side of the electrode assembly 120 is illustrated, but the positions and / or numbers of the cathode tab 120 aand the anode tab 120 bare exemplary. For example, in an embodiment not shown, the cathode tab 120 aand the anode tab 120 bmay be arranged with the electrode assembly 120 (e.g., cathode material 121, anode material 122, and separator 123) interposed therebetween. At least a portion of the cathode tab 120 aand the anode tab 120 bmay be disposed between the casing 110 and the electrode assembly 120, respectively.The cap plate 130 may be coupled to the case 110 to close an opening of the case 110. In the drawing, the cap plate 130 is illustrated as a square plate shape corresponding to the opening of the case 110.The cap plate 130 may be coupled to the case 110 to seal the accommodation space S of the case 110 in which the electrode assembly 120 is disposed. In some embodiments, the cap plate 130 may be welded to the shroud 110 by ultrasonic welding, laser welding, or the like. Terminal portions 131 aand 131 belectrically connected to the electrode assembly 120 may be disposed on the cap plate 130. The battery cell 10 may be electrically connected to an external power source through the terminal portions 131 aand 131 b. The terminal portions 131 aand 131 bmay include a cathode terminal 131 aand an anode terminal 131 b. The cathode terminal 131 amay be electrically connected to the cathode tab 120 aof the electrode assembly 120, and the anode terminal 131 bmay be electrically connected to the anode tab 120 bof the electrode assembly 120.The cap plate 130 may include a vent 133. In the present disclosure, it is illustrated that the vent 133 is disposed between the cathode terminal 131 aand the anode terminal 131 b, but the position of the vent 133 may be changed differently as needed and is not necessarily limited to what is illustrated. For example, in another embodiment not shown, a vent 133 may be disposed or added to the shroud 110.The vent 133 may be formed to be opened in response to an internal pressure of the jacket 110. In other words, the vent 133 may be provided to be opened by a predetermined pressure level, thereby allowing the accommodation space(s) and the exterior of the jacket 110 to be in communication. Thereby, the vent 133 can function to expel the internal pressure to the outside of the casing 110 and contribute to stabilizing internal elements of the casing 110.According to an embodiment of the present disclosure, the vent 133 may include a notch 133 aof a predetermined shape. The notch 133 amay be a fragile portion formed to be at least partially recessed in the thickness direction of the vent 133. Since the fracture of the vent 133 is caused by the difference between the pressure inside the accommodation space (S) or the pressure outside the jacket 110 from the notch, the accommodation space (S) of the jacket 110 may be in communication with the outside of the jacket.Meanwhile, in the present disclosure, a secondary battery 100 including a case 110 including an opening and a cap plate 130 disposed on one side of the case 110 is illustrated, but this is exemplary. In an embodiment not illustrated, a secondary battery 100 may be provided that includes a plurality of cap plates 130 disposed on both sides of the case 110. For example, the secondary battery 100 may include a first cap plate disposed on one side of the case 110 and a second cap plate disposed on the other side of the case 110.In addition, the present disclosure may include a liquid injection unit 134 that allows a fluid to flow by connecting the accommodation space (S) of the casing 110 and the outside of the casing 110 for exchange therebetween. The liquid injection unit 134 may be provided so that a fluid flowing into the accommodation space (S), such as an electrolyte, may flow. The liquid injection unit 134 may include an injection hole (not shown) formed in the cap plate 130 and an injection cap (not shown) sealing the injection hole. The fluid may be injected into the accommodation space (S) through the injection hole, and then the injection hole may be closed with the injection cap.Hereinafter, a vent cover 200 of the present disclosure will be described in detail with reference to the drawings.FIG. 3 is an exploded view of a vent cap, and FIG. 4 is an enlarged view of A in FIG. 2.Referring to FIGS. 3 and 4 together, the vent cover 200 may include a vent cap 210 including a support portion 213 and a vent film 230 mounted on the support portion 213 of the vent cap 210 and covering the vent 133.The vent cap 210 may support the vent film 230. The vent cap 210 may be disposed at a location where the vent 133 is provided between the cap plate 130 and the jacket 110, and support the vent film 230. The vent cap 210 may have a hole formed therein in communication with the vent 133, and include a support portion 213 that crosses over the hole. The vent cap 210 may support the vent film 230 by the support portion 213.The support portion 213 may be disposed to be spaced apart from the vent 133 by a predetermined distance in a first direction (Z-axis direction). Thereby, the vent cover 200 may further include a vent space (V) between the vent 133 and the vent film 230 therein.The vent film 230 may be installed in the support portion 213 to cut off the hole of the vent cap 210. The vent film 230 may include a first surface (lower surface) facing the vent 133 and a second surface (upper surface) opposite thereto.The vent film 230 may have a vent line 233 formed therein that is at least partially recessed in a thickness direction. The vent line 233 may be formed on the first surface (bottom surface) and / or the second surface (top surface). That is, the vent line 233 may be a vulnerable portion provided to be the first to be broken in the vent film 230.The support portion 213 of the vent cap 210 may be provided to support the vent line 233. In other words, the support portion 213 may be provided such that at least a portion thereof overlaps the vent line 233 in the first direction (Z-axis direction) to coincide with the vent line 233. That is, the support portion 213 may be provided to support a fragile portion of the air release film 230.Meanwhile, the vent line 233 may be formed by recessing the second surface (upper surface) of the vent film 230. As a result, a contact area between the air vent film 230 and the support portion 213 can be enlarged. However, as described above, this is merely an example of the present disclosure. For example, the vent line 233 may be provided by recessing from the first surface (bottom surface) of the vent film 230. As another example, the vent line 233 may be formed on both the first surface (bottom surface) and the second surface (top surface) of the vent film 230.Meanwhile, according to another embodiment of the present disclosure, only one vent cover 200 may be provided without one vent 133. According to another embodiment of the present disclosure, a case 110 accommodating the electrode assembly 120, a cap plate 130 coupled to at least one side of the case 110, and a vent cover 200 provided in the cap plate 130 or the case 110 and provided to be opened in a direction from the accommodation space S toward the outside of the case 110 may be included. Here, the vent cover 200 may include a vent film 230 provided to be opened by a predetermined pressure level and a vent line 233 formed on at least one of a first surface (lower surface) facing the accommodation space S in the first direction (Z-axis direction) or a second surface (upper surface) opposing the first surface; and a vent cap 210 having a support portion 213 that supports the first surface (lower surface) of the vent film 230. In this case, the support portion 213 may be provided such that a portion thereof overlaps the vent line 233 in the first direction (Z-axis direction) so that the vent film 230 is not broken even when a downward force (Z-axis direction) is applied. In the other embodiment, the configuration of the air vent cover 200 overlaps with that described above and is therefore omitted.Meanwhile, in the present disclosure, a space inside the case 110 may be defined as a storage space S, a space between the vent 133 and the vent film 230 may be defined as a vent space V, and the exterior of the case 110 may be referred to as an external space.The vent 133 may be provided to be broken and opened by a pressure between the accommodation space S and the vent space V. The vent film 230 may be provided to be broken by a pressure between the vent space V and the external space.In other words, the pressure generated inside the accommodation space S is first applied to the vent 133, and conversely, the pressure generated outside the jacket 110 may be first applied to the vent film 230. Here, when the vent film 230 is not broken by the pressure of gas or the like generated outside the jacket 110, the vent 133 cannot be opened. According to an embodiment of the present disclosure, the vent film 230 is provided so as not to be opened by the pressure generated outside the jacket 110, thereby preventing gas, flame, or the like flowing from the outside of the jacket from flowing into the inside (accommodation space: S) of the jacket 110. That is, according to the present disclosure, the vent cover 200 may be selectively opened depending on the direction of the force applied to the vent cover 200.Hereinafter, a structure of a vent cover that is selectively opened depending on a direction in which a pressure is applied will be described with reference to the drawings.FIG. 5 is a diagram exemplarily illustrating that a vent cover is opened to the exterior of a shroud, and FIG. 6 is a diagram exemplarily illustrating that reverse inflow of gas or the like flowing from the exterior of the shroud is prevented.Referring to FIG. 5, flames or gas (G) generated inside a receiving space S and ejected to the outside thereof crack the vent 133 and enter a vent space V, and then press the vent film 230 to bend it upward (in a +Z axis direction), thereby breaking the vent film 230. In this case, the venting film 230 may be broken along a venting line 233. Thereby, flames or gas (G) generated inside the accommodation space (S) can be ejected to the outside of the battery cell 10.As described above, the air vent cover 200 may be provided to be opened when the pressure in the accommodation space (S) becomes larger than the pressure outside the jacket 110 by a predetermined margin to be opened by a force from the accommodation space to the outside of the jacket 110.In addition, in an embodiment of the present disclosure, the vent 133 may be provided to be opened by a pressure difference between the accommodation space (S) and the vent space (V), and the vent film 230 may be provided to be opened to the outside of the casing 110 when the vent 133 is opened.On the other hand, referring to FIG. 6, flames or gas (E) flowing outside the battery cell 10 push the vent film 230 downward (in a -Z axis direction) from the outside of the vent film 230. In this case, the vent film 230 is supported by the support portion 213, so that the vent film 230 cannot be bent in a pressing direction. In particular, since the support portion 213 supports a lower surface of a portion where the vent line 233, which is a vulnerable portion of the vent film 230, is formed, the vent line 233 can be prevented from being broken by external flames or gas (E). This can prevent the external flames or gas (E) from breaking the vent 133 and flowing into the accommodation space (S). In addition, particles such as conductive particles contained in the external flames or gas (E) can be prevented from flowing back into the accommodation space (S).As described above, the battery cell 10 of the present disclosure may allow flames or gas (G) generated inside the accommodation space (S) to flow to the outside, but prevent or minimize flames or gas (E) generated from the outside thereof from flowing into the accommodation space (S).That is, whether the vent cover 200 is opened may be determined depending on the pressing direction (force) applied to the vent cover 200.FIG. 7 is a diagram illustrating a battery module according to an embodiment of the present disclosure, and FIG. 8 is a diagram exemplarily illustrating that an event has occurred in a battery cell in a battery module.Referring to FIG. 7, a battery module 50 according to an embodiment of the present disclosure may accommodate a plurality of battery cells 10. Here, the plurality of battery cells 10 may include at least one battery cell 10 of the present disclosure described above in FIGS. 1 to 6.In other words, the battery module 50 according to an embodiment of the present disclosure may include a plurality of battery cells 10 and a module case 510 that accommodates the plurality of battery cells 10. Here, at least one of the plurality of battery cells 10 may include a case 110 that houses an electrode assembly 120 in a housing space S, a cap plate 130 coupled to at least one side of the case, a vent 133 provided in the case 110 or the cap plate 130, and a vent cover 200 arranged to be opened by a pressure acting from the housing space S to the outside of the case. Here, the vent cover 200 may include a vent film 230 provided to be opened by a predetermined pressure level and including a first surface facing the vent 133 and a second surface opposite to the first surface, and a vent cap 210 having a support portion 213 that supports the first surface of the vent film 230.The housing 510 may include a bottom cover 512 having an interior space (M) formed therein and a top cover 511 coupled to the bottom cover 512 to close the interior space (M).In addition, the battery module 50 of the present disclosure may include a plurality of bus bars 520 electrically connecting the plurality of battery cells 10 to each other. The bus bar 520 may be formed of an electrically conductive material such as a metal, and may electrically connect terminals 131 aand 131 bof adjacent battery cells 10 to each other. In an embodiment not shown, the housing 510 may further include a module terminal electrically connected to an external power source, and the module terminal may be electrically connected to the bus bar 520.Referring to FIG. 8, when an event such as thermal runaway occurs in one (TS) of the plurality of battery cells 10, flames or gas (E) generated inside the battery cell 10 may be ejected into the interior space (M). The flames or gas (E) may increase the pressure inside the internal space (M) and flow toward an adjacent battery cell (BS), and as described above, the air vent cover 200 of the adjacent battery cell (BS) may prevent the flames or gas (E) from flowing into the internal space S. Thereby, the battery module 50 of the present disclosure can delay the occurrence of thermal runaway in one battery cell 10, which may cause a short circuit in the adjacent battery cell 10, as much as possible.As stated above, according to an embodiment of the present disclosure, when an event has occurred, a battery cell may emit flames, gas, or the like inside a storage space to the outside of a case, but may prevent flames, gases, or the like from flowing from the outside of the case into the storage space.According to an embodiment of the present disclosure, when an event has occurred, a battery module may expel flames, gas, or the like inside a storage space to the outside of a case, but may prevent flames, gas, or the like generated inside an adjacent battery cell from flowing into the battery module.The present disclosure may also relate to the following aspects.An aspect 1) of a battery cell, comprising: a case that accommodates an electrode assembly in an accommodation space; a cap plate coupled to at least one side of the case; a vent provided in the case or the cap plate; and a vent cover that is disposed to cover the vent and is provided to be opened by a pressure acting from the accommodation space to the outside of the case, wherein the vent cover includes a vent film provided to be opened by a predetermined pressure level and a first surface facing the vent and a second surface opposite to the first surface; and a vent cap having a support portion that supports the first surface of the vent film.Aspect 2) In Aspect 1, wherein the vent film includes a vent line formed on at least one of the first surface or the second surface.Aspect 3) In Aspect 1 or 2, wherein the vent film is arranged to face the vent in a first direction, and the support portion is arranged to conform to the vent line, and at least a portion of the support portion overlaps the vent line in the first direction.Aspect 4) In any of the preceding aspects, wherein the vent line is formed by being partially recessed from the second surface.Aspect 5) In one of the preceding aspects, wherein the vent is provided to be opened by a predetermined pressure level and to connect the accommodating space and the exterior of the casing.Aspect 6) In any of the preceding aspects, wherein the vent includes a notch groove formed by being at least partially recessed in a thickness direction.Aspect 7) In any one of the preceding aspects, wherein the vent cover is configured to be opened when a pressure inside the accommodation space becomes greater than a pressure outside the jacket by a predetermined margin to be opened by a force from the accommodation space to the outside of the jacket.Aspect 8) In any one of the preceding aspects, wherein the vent cover further includes a vent space formed between the vent film and the vent, the vent is provided to be opened by a pressure difference between the accommodation space and the vent space, and the vent film is provided to be opened to the outside of the casing when the vent is opened.Aspect 9) In any of the preceding aspects, wherein the vent includes a notch that is at least partially recessed in the first direction.Aspect 10) In one of the preceding aspects, wherein the support portion is arranged between the venting film and the vent.Aspect 11) In any of the preceding aspects, further comprising a terminal portion disposed on the cap plate and electrically connected to the electrode assembly, the terminal portion including: a cathode terminal electrically connected to a cathode tab of the electrode assembly; and an anode terminal electrically connected to an anode tab of the electrode assembly.Aspect 12) In Aspect 11, wherein the vent cover is disposed between the cathode terminal and the anode terminal.Aspect 13) In Aspects 11 or 12, wherein the vent is disposed between the cathode terminal and the anode terminal.Aspect 14) In any of the preceding aspects, wherein the vent lines are a plurality and the plurality of vent lines are arranged in a second direction perpendicular to the first direction.Aspect 15) In any one of the preceding aspects, wherein the support portion is provided in a plurality, and the plurality of support portions are arranged in the second direction.An aspect 16) battery module, comprising: a plurality of battery cells; and a module case accommodating the plurality of battery cells, wherein at least one of the plurality of battery cells includes a case accommodating an electrode assembly in an accommodation space; a cap plate coupled to at least one side of the case; a vent provided in the case or the cap plate; and a vent cover disposed to cover the vent and provided to be opened by a pressure acting from the accommodation space to the outside of the case, wherein the vent cover includes: a vent film provided to be opened by a predetermined pressure level and including a first surface facing the vent and a second surface opposite the first surface; and a vent cap having a support portion supporting the first surface of the vent film.A battery cell includes: a case accommodating an electrode assembly in a housing space; a cap plate coupled to at least one side of the case; a vent provided in the case or the cap plate; and a vent cover disposed to cover the vent and provided to be opened by a pressure acting from the housing space to the outside of the case, the vent cover including a vent film provided to be opened by a predetermined pressure level and a first surface facing the vent and a second surface opposite the first surface; and a vent cap having a support portion supporting the first surface of the vent film.

Claims

A battery cell (10) comprising: a case (110) that accommodates an electrode assembly (120) in a storage space; a cap plate (130) coupled to at least one side of the case (110); a vent (133) provided in the case (110) or the cap plate (130); and a vent cover (200) that is arranged to cover the vent (133) and is provided to be opened by a pressure acting from the storage space to the outside of the case (110), wherein the vent cover (200) includes: a vent film (230) provided to be opened by a predetermined pressure level and includes a first surface facing the vent (133) and a second surface opposite to the first surface; and a vent cap (210) having a support portion (213) that supports the first surface of the vent film (230).The battery cell (10) of claim 1, wherein the vent film (230) includes a vent line (233) formed on at least one of the first surface or the second surface.The battery cell (10) according to claim 1 or 2, wherein the vent film (230) is arranged to face the vent (133) in a first direction, and the support portion (213) is arranged to conform to the vent line (233), and at least a portion of the support portion (213) overlaps the vent line (233) in the first direction.The battery cell (10) of any preceding claim, wherein the vent line (233) is formed by being partially recessed from the second surface.The battery cell (10) according to any one of the preceding claims, wherein the vent (133) is provided to be opened by a predetermined pressure level and connect the accommodation space and the exterior of the case (110).The battery cell (10) according to any one of the preceding claims, wherein the vent (133) includes a notch groove formed by being at least partially recessed in a thickness direction.The battery cell (10) according to any one of the preceding claims, wherein the vent cover (200) is provided to be opened when a pressure inside the accommodation space becomes greater than a pressure outside the case (110) by a predetermined value to be opened by a force from the accommodation space to the outside of the case (110).The battery cell (10) according to any one of the preceding claims, wherein the vent cover (200) further includes a vent space formed between the vent film (230) and the vent (133), and the vent (133) is provided to be opened by a pressure difference between the accommodation space and the vent space, and the vent film (230) is provided to be opened to the outside of the case (110) when the vent (133) is opened.The battery cell (10) of any preceding claim, wherein the vent (133) includes a notch (133a) that is at least partially recessed in the first direction.The battery cell (10) according to any one of the preceding claims, wherein the support portion (213) is disposed between the venting foil (230) and the vent (133).The battery cell (10) of any one of the preceding claims, further comprising a terminal portion (131a, 131b) disposed on the cap plate (130) and electrically connected to the electrode assembly (120), wherein the terminal portion (131a, 131b) includes: a cathode terminal electrically connected to a cathode tab (120a) of the electrode assembly (120); and an anode terminal electrically connected to an anode tab (120b) of the electrode assembly (120).The battery cell (10) of claim 11, wherein the vent cover (200) is disposed between the cathode terminal and the anode terminal.The battery cell (10) of claim 11 or 12, wherein the vent (133) is disposed between the cathode terminal and the anode terminal.The battery cell (10) according to any one of the preceding claims, wherein the vent lines (233) are a plurality, and the plurality of vent lines (233) are arranged in a second direction perpendicular to the first direction.The battery cell (10) according to any one of the preceding claims, wherein the support portion (213) is provided in a plurality, and the plurality of support portions (213) are arranged in the second direction.A battery module (50) comprising: a plurality of battery cells (10); and a module housing (510) that houses the plurality of battery cells (10), wherein at least one of the plurality of battery cells (10) includes: a case (110) that houses an electrode assembly (120) in a housing space; a cap plate (130) coupled to at least one side of the case (110); a vent (133) provided in the case (110) or the cap plate (130); A vent cover (200) arranged to cover the vent (133) and provided to be opened by a pressure acting from the accommodation space to the outside of the jacket (110), the vent cover (200) including: a vent film (230) provided to be opened by a predetermined pressure level and including a first surface facing the vent (133) and a second surface opposing the first surface; and a vent cap (210) having a support portion (213) supporting the first surface of the vent film (230).

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