Battery module and battery pack

Abstract

Battery module, including: a lower frame including a plurality of receiving spaces and a partition wall dividing the plurality of receiving spaces; at least one battery cell accommodated in each of the plurality of accommodation spaces; a top cover disposed above the plurality of receiving spaces and including a primary vent hole; a primary barrier disposed on a surface of the top cover and including a porous structure; and a secondary barrier disposed on a surface of the primary barrier and containing a secondary vent hole, wherein the primary vent hole and the secondary vent hole are arranged to be offset from each other.

Description

TECHNICAL FIELD

[0001] The disclosure and implementations disclosed in this patent document generally relate to a battery module and a battery pack. BACKGROUND

[0002] Secondary batteries are a type of energy storage device that can be charged and discharged. Secondary batteries are widely used in various devices that use electricity as a power source. For example, secondary batteries are used as energy storage devices in a variety of devices, ranging from small devices such as mobile phones, laptops, and tablets to large devices such as vehicles and aircraft. In detail, secondary batteries have recently been actively researched as a vehicle power source.

[0003] Secondary batteries can be classified into lead-acid batteries, nickel-cadmium batteries, nickel-hydrogen batteries, lithium-ion batteries, and the like, depending on the electrode material or the like. Each type of secondary battery can be appropriately selected depending on the rated capacity, usage environment, or the like. Alternatively, the secondary battery may be an all-solid-state battery that uses a solid electrolyte instead of a liquid electrolyte. Lithium-ion batteries can achieve relatively high voltage and capacity compared to other types of secondary batteries. Accordingly, lithium-ion batteries are widely used in fields requiring high-density energy storage devices, such as vehicle battery packs.

[0004] Secondary batteries, such as lithium-ion batteries, may include a cathode, an anode, a separator, an electrolyte, and the like. The cathode and anode are arranged with a separator made of an insulating material between them, and charging or discharging can be accomplished by the movement of ions through the electrolyte.

[0005] Secondary batteries are manufactured as flexible pouch-type battery cells or rigid prismatic or cylindrical can-type battery cells.

[0006] A plurality of battery cells may be arranged within a module housing to form a battery module, and a plurality of battery modules may be arranged within a pack housing to form a battery pack.

[0007] In addition, recently the formation of a battery module is omitted, and the cell-to-pack process (CTP process) in which the battery cells are directly integrated into the battery pack and the battery pack is connected to the main body frame is used.

[0008] Meanwhile, when heat propagation occurs in the battery module, a re-entry phenomenon may occur in which a gas, flame, or foreign matter discharged through the vent hole collides with an external component and then re-enters the interior of the battery module. SUMMARY

[0009] The present disclosure may be implemented in some embodiments to prevent a re-entry phenomenon.

[0010] According to one aspect of the present disclosure, heat propagation may be delayed.

[0011] The battery pack of the present disclosure can be widely applied in green technology fields such as electric vehicles, battery charging stations, and solar and wind power generation using batteries. Additionally, the battery pack of the present disclosure can be used in environmentally friendly electric vehicles, hybrid vehicles, and the like to prevent climate change by suppressing air pollution and greenhouse gas emissions.

[0012] In some embodiments of the present disclosure, a battery module includes a bottom frame including a plurality of accommodation spaces and a partition wall dividing the plurality of accommodation spaces; at least one battery cell accommodated in each of the plurality of accommodation spaces; a top cover disposed above the plurality of accommodation spaces and including a primary vent hole; a primary barrier disposed on a surface of the top cover and including a porous structure; and a secondary barrier disposed on a surface of the primary barrier and including a secondary vent hole. The primary vent hole and the secondary vent hole are arranged to be offset from each other.

[0013] In one embodiment, the primary vent hole and the secondary vent hole may be arranged so as not to face each other in a first direction perpendicular to the top cover.

[0014] In one embodiment, the primary vent hole and the secondary vent hole may be arranged so that they do not overlap each other in a first direction perpendicular to the top cover.

[0015] In one embodiment, the partition may be arranged so that it does not overlap the primary vent hole in a first direction perpendicular to the top cover.

[0016] In one embodiment, the partition wall can be arranged parallel to the at least one battery cell.

[0017] In one embodiment, the partition may be arranged so that it is perpendicular to the top cover.

[0018] In one embodiment, the partition wall may be arranged to face a region located beneath portions of the top cover between a plurality of the primary vent holes.

[0019] In one embodiment, the primary barrier may include a metallic material.

[0020] In one embodiment, the primary barrier may include at least one of a metal foam, a metal mesh, a steel wool wire, or a porous steel sheet.

[0021] In one embodiment, the secondary barrier may include a metallic material.

[0022] In one embodiment, the secondary barrier may be formed from a metallic shielding foil.

[0023] In one embodiment, the primary vent hole and the secondary vent hole may be configured to expel a gas, flame, or foreign matter generated in at least one of the plurality of receiving spaces to the outside.

[0024] In one embodiment, the primary vent hole may be arranged to be offset from the secondary vent hole to block a gas, flame, or foreign matter flowing in from an exterior side of the secondary barrier through the secondary vent hole.

[0025] In some embodiments of the present disclosure, a battery pack includes a plurality of battery modules; and a pack frame that accommodates the plurality of battery modules. Each of the plurality of battery modules includes a bottom frame that includes a plurality of accommodation spaces and a partition wall that divides the plurality of accommodation spaces; at least one battery cell accommodated in each of the plurality of accommodation spaces; a top cover disposed above the plurality of accommodation spaces and including a primary vent hole; a primary barrier disposed on a surface of the top cover and including a porous structure; and a secondary barrier disposed on a surface of the primary barrier and including a secondary vent hole. The primary vent hole and the secondary vent hole are arranged to be offset from each other.

[0026] In one embodiment, the packing frame may include a packing cover disposed above the secondary barrier. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] 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. Fig. 2 is a perspective exploded view of a battery module according to an embodiment. Fig. 3 is a plan view illustrating a portion of a battery module according to an embodiment. Fig. 4 is a cross-sectional view illustrating a portion of a battery module according to an embodiment. Fig. 5 is a perspective exploded view of a battery pack according to one embodiment. Fig. 6 is a cross-sectional view illustrating a portion of a battery pack according to an embodiment. Fig. 7 is a cross-sectional view illustrating a portion of a battery pack according to an embodiment. DETAILED DESCRIPTION

[0028] Features of the present disclosure disclosed in this patent document will be described by way of exemplary embodiments with reference to the accompanying drawings.

[0029] Hereinafter, embodiments of the present disclosure will be described with reference to the accompanying drawings.

[0030] Fig. 1 is a perspective view of a battery module 100 according to an embodiment, Fig. 2 is a perspective exploded view of a battery module 100 according to an embodiment, Fig. 3 is a plan view illustrating a portion of a battery module 100 according to an embodiment, and Fig. 4 is a cross-sectional view illustrating a portion of a battery module 100 according to one embodiment.

[0031] With reference to Fig. 1 to Fig. 4, the battery module 100 may include a lower frame 110, at least one battery cell 130, a top cover 140, a primary barrier 150, and a secondary barrier 160.

[0032] The lower frame 110 is a frame located in a lower portion of the battery module 100 and may include a plurality of receiving spaces 111. Each of the plurality of receiving spaces 111 may accommodate at least one battery cell 130. Each of the plurality of receiving spaces 111 may include a space sufficient to accommodate at least one battery cell 130. The plurality of receiving spaces 111 may be formed in various shapes and may, for example, include a shape similar to a rectangular parallelepiped.

[0033] The lower frame 110 may include a partition wall 120 that divides the plurality of receiving spaces 111. The lower frame 110 includes a receiving space, and the partition wall 120 may divide the receiving space into a plurality of sections. The partition wall 120 may be arranged so that it is erected on the underside of the lower frame 110, and both ends of the partition wall 120 may be connected to the side walls of the lower frame 110. The plurality of receiving spaces 111 may each be isolated by the partition wall 120.

[0034] The partition wall 120 may be arranged so that it does not overlap the primary vent hole 141 in a first direction perpendicular to the top cover 140. Specifically, the primary vent hole 141 and the partition wall 120 may not overlap each other when viewed in the first direction. For example, the primary vent hole 141 may be located only on one accommodation space and may not be located on two adjacent accommodation spaces. Therefore, if a fire occurs in one accommodation space, the fire can be prevented from spreading to the adjacent accommodation space through the primary vent hole 141.

[0035] Additionally, the partition wall 120 may be arranged parallel to at least one battery cell 130. For example, if the battery cell 130 is a pouch-type secondary battery, a surface of the partition wall 120 may be arranged to face the side surface of the battery cell 130. The partition wall 120 may be arranged to be perpendicular to the top cover 140. In detail, the partition wall 120 may be arranged to be upright in the first direction.

[0036] The partition wall 120 may be arranged to face a region located below the regions of the top cover 140 between a plurality of primary vent holes 141. For example, the primary vent hole 141 may be arranged to be spaced apart from another adjacent primary vent hole 141 by a certain distance. At this time, the region between the primary vent holes 141 and the partition wall 120 may face each other. The upper portion of the partition wall 120 may be in contact with the top cover 140, or a flexible printed circuit board (FPCB) frame 170 and the like may be interposed therebetween. However, the configuration of the flexible printed circuit board (FPCB) frame 170 or the like is not an essential configuration and may be omitted as needed.

[0037] The battery cell 130 may be formed of a lithium secondary battery, but is not limited thereto. For example, the battery cell 130 may be formed of various types of secondary batteries, such as a nickel-cadmium battery, a nickel-metal hydride battery, and a nickel-hydrogen battery. The battery cell 130 may be formed of a pouch-type secondary battery. Below, a case where a pouch-type secondary battery is used as the battery cell 130 will be described as an example. However, the present disclosure does not preclude the use of a can-type secondary battery, such as a prismatic secondary battery or a cylindrical secondary battery, as the battery cell 130.

[0038] At least one battery cell 130 can be accommodated in each of the plurality of accommodation spaces 111. If multiple battery cells 130 are present, the plurality of battery cells 130 can be arranged in a specific direction (X) and can be stacked. Each battery cell 130 can output or store electrical energy.

[0039] The top cover 140 may be a cover disposed in the upper portion of the battery module 100. The top cover 140 may cover the upper portion of the battery module 100. For example, the top cover 140 may have a plate shape and may cover the upper portions of a plurality of receiving spaces 111.

[0040] The top cover 140 may include a primary vent hole 141. The primary vent hole 141 may be a hole that expels a gas, flame, or foreign matter (hereinafter, a gas) generated within the battery module 100 to the outside. For example, when a fire occurs in at least one battery cell 130 housed in a plurality of housing spaces 111, the pressure within the plurality of housing spaces 111 may rise. At this time, the gas or the like may be expelled to the outside through the primary vent hole 141 located in the upper portion.

[0041] The primary barrier 150 may be disposed on a surface of the top cover 140. The primary barrier 150 may be disposed on the upper surface of the top cover 140. The primary barrier 150 may cover the top cover 140. For example, the primary barrier 150 includes a plate shape and may cover the upper portion of the top cover 140. In detail, the primary barrier 150 may be disposed to cover the primary vent hole 141 in the upper portion of the top cover 140. At this time, the primary vent holes 141 may be distributed in the top cover 140, and all of the primary vent holes 141 may be covered.

[0042] The primary barrier 150 may include a porous structure. A fire or gas generated within the battery module 100 may flow through the primary vent hole 141 and then be expelled to the outside through the porous structure of the primary barrier 150. At this time, the pressure can be reduced, the expulsion speed can be slowed, or trapped foreign matter can be filtered out due to the porous structure of the primary barrier 150. The primary barrier 150 may include a material with heat resistance or fire resistance. For example, the primary barrier 150 may include a metallic material. The metallic material may include steel, aluminum, nickel, or the like. The primary barrier 150 may include various shapes with a porous structure.For example, the primary barrier 150 may include at least one of a metal foam, a metal mesh, a steel wool wire, or a porous steel sheet. The metal foam, the metal mesh, and the steel wool wire may have a porous structure or shape.

[0043] The secondary barrier 160 may be disposed on a surface of the primary barrier 150. The secondary barrier 160 may be disposed on the upper surface of the primary barrier 150. The secondary barrier 160 may cover the primary barrier 150. The secondary barrier 160 may be configured to include an area equal to or larger than that of the primary barrier 150 to cover the primary barrier 150. The secondary barrier 160 may include a plate shape to cover the primary barrier 150.

[0044] The secondary barrier 160 may include a secondary vent hole 161. The secondary vent hole 161 may be a hole that expels gas and the like generated within the battery module 100 to the outside. Specifically, the gas may first pass through the primary vent hole 141, then pass through the porous structure of the primary barrier 150, and then be expelled to the outside through the secondary vent hole 161.

[0045] At this time, the primary vent hole 141 and the secondary vent hole 161 may be arranged alternately. Alternating may mean that the primary vent hole 141 and the secondary vent hole 161 are not adjacent to each other or that their centers do not coincide. In detail, the secondary vent hole 161 may be arranged alternately with the primary vent hole 141 so that the gas discharged through the primary vent hole 141 cannot be discharged while maintaining the same movement direction.

[0046] The primary vent hole 141 and the secondary vent hole 161 may be arranged so that they do not face each other in the first direction. For example, when the secondary vent hole 161 is viewed from the first direction, the primary vent hole 141 may not be visible. In detail, the primary vent hole 141 and the secondary vent hole 161 may not overlap each other in the first direction. In detail, the primary vent hole 141 and the secondary vent hole 161 may be arranged so that they do not overlap each other in the first direction, which is a direction perpendicular to the top cover 140. In detail, the area of ​​the primary vent hole 141 and the area of ​​the secondary vent hole 161 may not overlap each other in the first direction.

[0047] The primary vent hole 141 and the secondary vent hole 161 may be configured to expel a gas generated in at least one of the plurality of accommodation spaces 111 to the outside. Since the primary vent hole 141 and the secondary vent hole 161 are alternately arranged, at least one path change occurs during the gas expulsion process, thereby delaying the heat propagation situation. In detail, even if the gas flows through the primary vent hole 141, the path can be changed or delayed by the porous structure of the primary barrier 150, and after the path change, the gas can be expelled to the outside through the secondary vent hole 161.

[0048] Additionally, the primary vent hole 141 may be arranged alternately with the secondary vent hole 161 to block a gas flowing in through the secondary vent hole 161 from the outside of the secondary barrier 160. The gas expelled to the exterior of the battery module 100 may return to the battery module 100 after encountering an external component. However, even if the returned gas flows through the secondary vent hole 161, the gas cannot easily flow through the primary vent hole 141 because it would again flow through the porous structure of the primary barrier 150. In addition, the primary vent hole 141 is arranged to be offset from the secondary vent hole 161, so that the incoming gas may have difficulty passing through the primary vent hole 141. The path of this gas is described with reference to the following Fig. 6 and Fig. 7 described again.

[0049] The secondary barrier 160 may include a material with heat resistance or fire resistance. For example, the secondary barrier 160 may include a metallic material. The metallic material may include steel, aluminum, nickel, and the like. The secondary barrier 160 may be formed from a metallic shielding foil. For example, the secondary barrier 160 may be a metallic plate with shielding properties with a secondary vent hole 161 perforated therein. Therefore, gas and the like, except for the secondary vent hole 161, cannot flow through other parts of the secondary barrier 160.

[0050] Fig. 5 is a perspective exploded view of a battery pack 10 according to an embodiment, Fig. 6 is a cross-sectional view illustrating a portion of a battery pack 10 according to an embodiment, and Fig. 7 is a cross-sectional view illustrating a portion of a battery pack 10 according to one embodiment.

[0051] With reference to Fig. 5 to Fig. 7, the battery pack 10 may include a plurality of battery modules 100 and a pack frame 200.

[0052] The plurality of battery modules 100 may be an assembly in which a plurality of battery modules 100 are assembled. Each battery module 100 may be one of the Fig. 1 to Fig. 4 described battery modules 100.

[0053] The packing frame 200 can accommodate a plurality of battery modules 100. For example, the packing frame 200 can include a base frame 210 located at a lower portion and a packing cover 220 covering the upper portion thereof. The base frame 210 can include a receiving space that accommodates the battery module 100. The receiving space is formed into multiple units, and a battery module 100 can be accommodated in each receiving space.

[0054] The pack cover 220 may be arranged above the secondary barrier 160. For example, when a plurality of battery modules 100 are accommodated in the accommodation spaces of the base frame 210, the pack cover 220 may be combined with the base frame 210. At this time, the pack cover 220 includes a plate shape, and the secondary barrier 160 of each battery module 100 may face the pack cover 220. For example, the pack cover 220 may be arranged on the plurality of upper covers 140. The pack cover 220 may be arranged on the upper parts of the primary barrier 150 and the secondary barrier 160. The pack cover 220 may be arranged on a surface of the secondary barrier 160 to cover the upper surface of the secondary barrier 160.

[0055] The pack cover 220 may be an external component of the Fig. 1 to Fig. 4. Accordingly, the gas (G) discharged from the battery module 100 may return to the battery module 100 after impacting the pack cover 220. This phenomenon is called re-entry, and the primary vent hole 141 and the secondary vent hole 161, which are alternately arranged, can prevent the re-entry phenomenon.

[0056] The Fig. 6 and Fig. 7 illustrate a heat propagation situation. The movement path of the gas (G) generated by the battery cell 130 is indicated by a dotted line.

[0057] With reference to Fig. 6, gas (G) can be expelled through the primary vent hole 141. Then, gas (G) can pass through the porous structure of the primary barrier 150. Then, gas (G) can encounter the secondary barrier 160 and again pass through the porous structure of the primary barrier 150. Then, gas (G) can encounter the upper portion of the top cover 140 and again pass through the porous structure of the primary barrier 150. Then, gas (G) can be expelled through the secondary vent hole 161 and return by encountering an external component or pack cover 220. Then, the gas (G) can encounter the upper surface of the secondary barrier 160.

[0058] Or, with reference to Fig. 7, the gas (G) that has returned after hitting the external configuration or pack cover 220 flows through the secondary vent hole 161 and then hits the primary barrier 150.

[0059] The gas (G) can reduce its velocity and temperature through the above-mentioned multiple processes, such as path change, collision, filtering, and the like. Therefore, the structure of the battery module 100 or battery pack 10 of the present disclosure can delay heat propagation and prevent the re-entry phenomenon.

[0060] As set forth above, according to one embodiment, a re-entry phenomenon can be prevented.

[0061] According to one embodiment, heat propagation can be delayed.

[0062] Only specific examples of implementations of particular embodiments are described. Variations, improvements, and enhancements to the disclosed embodiments and other embodiments may be made based on the disclosure of this patent document.

[0063] (Aspect 1) A battery module comprising: a lower frame including a plurality of accommodation spaces and a partition wall dividing the plurality of accommodation spaces; at least one battery cell accommodated in each of the plurality of accommodation spaces; an upper cover disposed above the plurality of accommodation spaces and including a primary vent hole; a primary barrier disposed on a surface of the upper cover and including a porous structure; and a secondary barrier disposed on a surface of the primary barrier and including a secondary vent hole, wherein the primary vent hole and the secondary vent hole are arranged to be offset from each other.

[0064] (Aspect 2) The battery module according to aspect 1, wherein the primary vent hole and the secondary vent hole are arranged so as not to face each other in a first direction perpendicular to the top cover.

[0065] (Aspect 3) The battery module according to aspect 1 or 2, wherein the primary vent hole and the secondary vent hole are arranged so as not to overlap in a first direction perpendicular to the top cover.

[0066] (Aspect 4) The battery module according to any one of aspects 1 to 3, wherein the partition wall is arranged so as not to overlap the primary vent hole in a first direction perpendicular to the top cover.

[0067] (Aspect 5) Battery module according to one of aspects 1 to 4, wherein the partition wall is arranged parallel to the at least one battery cell.

[0068] (Aspect 6) The battery module according to any one of aspects 1 to 5, wherein the partition wall is arranged to be perpendicular to the top cover.

[0069] (Aspect 7) The battery module according to any one of aspects 1 to 6, wherein the partition wall is arranged to face a region located under regions of the top cover between a plurality of the primary vent holes.

[0070] (Aspect 8) A battery module according to any one of aspects 1 to 7, wherein the primary barrier comprises a metallic material.

[0071] (Aspect 9) The battery module according to any one of aspects 1 to 8, wherein the primary barrier includes at least one of a metal foam, a metal mesh, a steel wool wire, or a porous steel sheet.

[0072] (Aspect 10) A battery module according to any one of aspects 1 to 9, wherein the secondary barrier comprises a metallic material.

[0073] (Aspect 11) Battery module according to any one of aspects 1 to 10, wherein the secondary barrier is formed from a metallic shielding foil.

[0074] (Aspect 12) The battery module according to any one of aspects 1 to 11, wherein the primary vent hole and the secondary vent hole are configured to discharge a gas, a flame, or foreign matter generated in at least one of the plurality of accommodating spaces to the outside.

[0075] (Aspect 13) The battery module according to any one of aspects 1 to 12, wherein the primary vent hole is arranged to be offset from the secondary vent hole to block a gas, flame, or foreign matter flowing in through the secondary vent hole from an outside of the secondary barrier.

[0076] (Aspect 14) A battery pack comprising: a plurality of battery modules; and a pack frame that accommodates the plurality of battery modules, each of the plurality of battery modules including a lower frame including a plurality of accommodation spaces and a partition wall dividing the plurality of accommodation spaces; at least one battery cell accommodated in each of the plurality of accommodation spaces; a top cover disposed above the plurality of accommodation spaces and including a primary vent hole; a primary barrier disposed on a surface of the top cover and including a porous structure; and a secondary barrier disposed on a surface of the primary barrier and including a secondary vent hole, wherein the primary vent hole and the secondary vent hole are arranged to be offset from each other.

[0077] (Aspect 15) The battery pack of aspect 14, wherein the pack frame includes a pack cover disposed above the secondary barrier.

[0078] A battery module includes a bottom frame containing a plurality of accommodation spaces and a partition wall dividing the plurality of accommodation spaces; at least one battery cell housed in each of the plurality of accommodation spaces; a top cover disposed above the plurality of accommodation spaces and including a primary vent hole; a primary barrier disposed on a surface of the top cover and including a porous structure; and a secondary barrier disposed on a surface of the primary barrier and including a secondary vent hole. The primary vent hole and the secondary vent hole are arranged to be offset from each other.

Claims

[1] Battery module, including: a lower frame including a plurality of receiving spaces and a partition wall dividing the plurality of receiving spaces; at least one battery cell accommodated in each of the plurality of accommodation spaces; a top cover disposed above the plurality of receiving spaces and including a primary vent hole; a primary barrier disposed on a surface of the top cover and including a porous structure; and a secondary barrier disposed on a surface of the primary barrier and containing a secondary vent hole, wherein the primary vent hole and the secondary vent hole are arranged to be offset from each other. [2] The battery module according to claim 1, wherein the primary vent hole and the secondary vent hole are arranged not to face each other in a first direction perpendicular to the top cover. [3] The battery module according to claim 1 or 2, wherein the primary vent hole and the secondary vent hole are arranged not to overlap each other in a first direction perpendicular to the top cover. [4] The battery module according to any one of claims 1 to 3, wherein the partition wall is arranged not to overlap the primary vent hole in a first direction perpendicular to the top cover. [5] Battery module according to one of claims 1 to 4, wherein the partition wall is arranged parallel to the at least one battery cell. [6] The battery module according to any one of claims 1 to 5, wherein the partition wall is arranged to be perpendicular to the top cover. [7] The battery module according to any one of claims 1 to 6, wherein the partition wall is arranged to face a region located, among regions of the top cover, between a plurality of the primary vent holes. [8] Battery module according to one of claims 1 to 7, wherein the primary barrier contains a metallic material. [9] A battery module according to any one of claims 1 to 8, wherein the primary barrier comprises at least one of a metal foam, a metal mesh, a steel wool wire, or a porous steel sheet. [10] Battery module according to one of claims 1 to 9, wherein the secondary barrier contains a metallic material. [11] Battery module according to one of claims 1 to 10, wherein the secondary barrier is formed from a metallic shielding foil. [12] The battery module according to any one of claims 1 to 11, wherein the primary vent hole and the secondary vent hole are configured to discharge a gas, a flame, or foreign matter generated in at least one of the plurality of accommodation spaces to the outside. [13] The battery module according to any one of claims 1 to 12, wherein the primary vent hole is arranged to be offset from the secondary vent hole to block a gas, flame, or foreign matter flowing in through the secondary vent hole from an exterior of the secondary barrier. [14] Battery pack, including: a variety of battery modules; and a packing frame that accommodates the multitude of battery modules, wherein each of the plurality of battery modules includes: a lower frame including a plurality of receiving spaces and a partition wall dividing the plurality of receiving spaces; at least one battery cell accommodated in each of the plurality of accommodation spaces; a top cover disposed above the plurality of receiving spaces and including a primary vent hole; a primary barrier disposed on a surface of the top cover and including a porous structure; and a secondary barrier disposed on a surface of the primary barrier and containing a secondary vent hole, wherein the primary vent hole and the secondary vent hole are arranged to be offset from each other. [15] The battery pack of claim 14, wherein the pack frame includes a pack cover disposed above the secondary barrier.

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