Battery pack and automobile including same

Abstract

According to one aspect of the present invention, a battery pack includes a cell array including a plurality of battery cells, and a pack case that houses the cell array, the pack case including a vent device that is arranged to exhaust gas generated from the cell array to the outside of the pack case, and a rib that is arranged under the cell array and guides the gas to the vent device.

Description

[Technical field]

[0001] The present invention relates to a battery pack and a vehicle including the same, and more particularly, to a battery pack and a vehicle including the same that can smoothly discharge gases and the like to the outside of a pack case when a battery cell is vented.

[0002] This application claims priority to Korean Patent Application No. 10-2022-0181098 filed on December 21, 2022, the entire contents of which are incorporated herein by reference in their entirety in the specification and drawings.

[0003] This application also claims priority based on Korean Patent Application No. 10-2023-0062677, filed on May 15, 2023, the entire contents of which are incorporated herein by reference in their entirety in the specification and drawings. [Background technology]

[0004] Secondary batteries, which have high applicability to various products and electrical properties such as high energy density, are widely used not only in portable devices but also in electric vehicles (EVs) and hybrid electric vehicles (HEVs) that are driven by electric drive sources. These secondary batteries have the primary advantage of dramatically reducing the use of fossil fuels, as well as the advantage of not producing any by-products associated with energy use, and are therefore attracting attention as a new energy source that is environmentally friendly and improves energy efficiency.

[0005] Currently, the types of secondary batteries that are widely used include lithium ion batteries, lithium polymer batteries, nickel cadmium batteries, nickel hydrogen batteries, and nickel zinc batteries. The operating voltage of such a unit secondary battery cell, i.e., a unit battery cell, is about 2.5V to 4.5V. Therefore, when a higher output voltage is required, a battery pack is constructed by connecting a plurality of batteries in series. In addition, a battery pack may be constructed by connecting a plurality of battery cells in parallel depending on the charge / discharge capacity required for the battery pack. Therefore, the number of batteries included in the battery pack may be variously set depending on the required output voltage or charge / discharge capacity.

[0006] Meanwhile, when configuring a battery pack by connecting multiple battery cells in series / parallel, a common method is to first configure a battery module including at least one battery cell, and then use the at least one battery module to add other components to configure a battery pack or a battery rack.

[0007] In battery packs and battery modules using conventional battery cells, the internal temperature may rise due to abnormality or misuse of the battery cells, which may cause the internal pressure of the battery cells to rise. Such internal pressure may cause the battery cells to vent or explode, and if the released high-temperature gas or flames are transferred to adjacent battery cells, it may cause a chain reaction of battery cell explosions, which is extremely dangerous.

[0008] Therefore, for example, conventional cylindrical battery cells are usually manufactured to include a vent structure on the upper side of the cylindrical battery cell where the positive electrode terminal is formed, and in a battery pack or battery module that houses such cylindrical battery cells in an upright position, a predetermined space is provided in the direction in which the cylindrical battery cell vents or explodes, i.e., on the upper side of the top cover of the pack case or module case that faces the vent structure of the cylindrical battery cell, and the configuration is such that high-temperature gas or flame can escape, thereby delaying or preventing the transfer of high-temperature gas or flame to other battery cells.

[0009] However, with such conventional structures, it is difficult for high-temperature gases and flames to be directed solely to the upper part of the top cover, and they end up scattering in all directions from inside the battery pack or battery module. This places a limit on how efficiently these gases and flames can be exhausted to the outside of the battery pack or battery module, and improvements are needed. Summary of the Invention [Problem to be solved by the invention]

[0010] Therefore, one problem to be solved by the present invention is to provide a battery pack and a vehicle including the same that can more efficiently exhaust high-temperature gas and flames to the outside of the battery pack when an abnormality occurs in a battery cell.

[0011] However, the technical problems that the present invention aims to solve are not limited to the problems described above, and other problems not mentioned will be clearly understood by those skilled in the art from the description of the invention described below. [Means for solving the problem]

[0012] In order to solve the above problems, the present invention provides a battery pack comprising: a cell array including a plurality of battery cells; and a pack case accommodating the cell array, wherein the pack case comprises a venting device arranged to exhaust gas generated from the cell array to the outside of the pack case; and a rib arranged under the cell array to guide the gas to the venting device.

[0013] The rib may be provided to be in surface contact with a lower surface of the cell array.

[0014] The rib may be adhesively secured to a lower surface of the cell array.

[0015] The pack case may include a case frame having an open top and bottom and accommodating the cell array, and a bottom cover covering a bottom of the case frame and coupled to the case frame.

[0016] The ribs may be provided on the bottom cover in a plurality of portions spaced apart from each other along one direction of the bottom cover.

[0017] The ribs may define at least one vent passage through which the gas flows, the vent passage being in communication with the vent device.

[0018] The bottom cover may be extruded such that the ribs are integrally formed with the bottom cover.

[0019] The vent device may be provided on one side of the case frame, and the case frame may include a gas inlet provided between the vent passage and the vent device and through which the gas can pass.

[0020] The gas inlet may be provided independently for each of the vent passages.

[0021] The gas inlet may be formed in a rectangular shape such that the width of the gas inlet corresponds to the spacing between the ribs.

[0022] According to another aspect of the present invention, the gas inlets may be integrally provided.

[0023] The case frame may include a side gas channel therein connected to the gas inlet and the vent device so that the gas can flow therethrough.

[0024] The side gas channel may be formed along an extension direction of the case frame.

[0025] The bottom cover may include a plurality of bottom plates joined together by friction stir welding.

[0026] The case frame and the bottom cover may be joined by friction stir welding.

[0027] The vent devices may be provided on both sides of the case frame.

[0028] The rib may extend in a direction in which the vent device is located.

[0029] The case frame may include an indentation for receiving the vent device.

[0030] The pack case may accommodate a plurality of the cell arrays, and the case frame may further include partition walls that partition the plurality of cell arrays.

[0031] The vent device may be provided to correspond to each of the plurality of cell arrays.

[0032] The present invention also provides a motor vehicle, characterized in that it comprises a battery pack according to the present invention. Effect of the Invention

[0033] According to the present invention, a battery pack is provided that can efficiently guide high-temperature gas and flames that may be generated in the event of an abnormal condition in a battery cell to a vent device, thereby ensuring the safety and reliability of the battery pack.

[0034] In addition, if a thermal event occurs in a battery cell and high-temperature gas or flame is generated, the high-temperature gas or flame can be guided in a specific direction and quickly discharged to the outside of the pack case.

[0035] In addition, in the process of discharging high-temperature gas vented from the battery cells to the outside of the pack case, other battery cells can be prevented from being thermally damaged as much as possible.

[0036] In addition, by separating the space through which gas vented from the battery cells flows into multiple regions inside the pack case, the gas exhaust paths can be diversified and the total exhaust volume can be increased. Therefore, even if a large amount of gas is generated, the gas can be smoothly and quickly exhausted to the outside of the battery pack.

[0037] In addition to these, the present invention can have various other effects, which will be described in the sections for each embodiment, and descriptions of effects that can be easily inferred by a person skilled in the art will be omitted.

[0038] The drawings attached to this specification are intended to illustrate preferred embodiments of the present invention and serve to facilitate a further understanding of the technical ideas of the present invention as well as the content of the invention, and therefore the present invention should not be interpreted as being limited to only the matters depicted in the drawings. [Brief description of the drawings]

[0039] [Figure 1] 1 is an assembled perspective view of a battery pack according to an embodiment of the present invention; [Diagram 2] FIG. 2 is an exploded perspective view of the battery pack of FIG. 1. [Diagram 3] 3 is a cross-sectional view of the battery pack taken along line III-III' in FIG. 1. [Figure 4] FIG. 4 is an enlarged view of part A in FIG. [Diagram 5] 2 is a diagram for explaining a gas discharge direction during venting of a battery cell in the battery pack of FIG. 1. FIG. [Figure 6] FIG. 6 is an enlarged view of a vent device included in the battery pack of FIG. 5. [Figure 7] FIG. 6 is an enlarged view of a gas inlet included in the case frame of the battery pack of FIG. 5. [Figure 8] 11A and 11B are diagrams illustrating another embodiment of a gas inlet of a battery pack. [Figure 9] 2A to 2C are diagrams for explaining a method of manufacturing a bottom cover included in the battery pack of FIG. 1. [Figure 10] 2A to 2C are diagrams for explaining a method of manufacturing a pack case included in the battery pack of FIG. 1. [Figure 11] FIG. 2 is a perspective view of a vehicle including the battery pack of FIG. 1. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0040] Hereinafter, a preferred embodiment of the present invention will be described in detail with reference to the attached drawings. Prior to this, the terms and words used in the present specification and claims are not to be construed as being limited to their ordinary or dictionary meanings, but are to be construed as having meanings and concepts corresponding to the technical ideas of the present invention, in accordance with the principle that the inventor can appropriately define the concepts of terms himself / herself in order to best describe the invention.

[0041] Therefore, it should be understood that the embodiment described in this specification and the configurations shown in the drawings are merely the most preferred embodiment of the present invention and do not represent the entire technical idea of ​​the present invention, and therefore there may be various equivalents and modifications that can be substituted therefor at the time of this application.

[0042] FIG. 1 is an assembled perspective view of a battery pack according to an embodiment of the present invention, and FIG. 2 is an exploded perspective view of the battery pack of FIG.

[0043] 1 and 2, a battery pack 10 according to an embodiment of the present invention includes a cell array 100 including a plurality of battery cells 110, and a pack case 200 housing the cell array 100.

[0044] The cell array 100 is an assembly of battery cells 110. In order to collect the battery cells 110 into a single unit, a binder such as a resin may be filled between the battery cells 110. As another example, the cell array 100 may be a battery module including a module housing 120 that houses the battery cells 110. The module housing 120 may be made of a material with high mechanical rigidity, preferably a metal material, to protect the battery cells 110 from external impacts and vibrations.

[0045] The battery cell 110 may be a secondary battery having any shape, such as a rectangular, cylindrical, or pouch-type battery cell, and in the present embodiment, the battery cell 110 is a cylindrical battery cell. In particular, the battery cell 110 may include a vent structure such as a vent notch at the bottom of the battery cell 110, even though the battery cell 110 is a cylindrical battery cell. The vent notch is broken when the pressure inside the battery cell 110 increases abnormally, thereby discharging the internal gas to the outside. In this manner, when the vent notch is included at the bottom of the battery cell 110, this can help guide the discharge direction of the vent gas downward of the battery pack 10. In the cell array 100, a plurality of battery cells 110 may be arranged in columns and rows. A plurality of such cell arrays 100 may be provided in the battery pack 10.

[0046] The pack case 200 includes a vent device 224 provided to exhaust gas generated from the cell array 100 to the outside of the pack case 200, and a rib 233 provided under the cell array 100 to guide the gas to the vent device 224. The vent device 224 and the rib 233 are characterized in that they are disposed at a position lower than the cell array 100.

[0047] The pack case 200 accommodates a plurality of the cell arrays 100, and the case frame 220 may further include partition walls 223 that partition the plurality of cell arrays 100. The partition walls 223 may be plural and may be spaced apart at regular intervals.

[0048] The cell array 100 may be accommodated in the pack case 200 while being partitioned by the partition wall 223 and supported by the rib 233. By forming the vent structure of the battery cell 110 included in the cell array 100 at the bottom side of the battery cell 110 as described above, high-temperature gas discharged downward through the vent structure of the battery cell 110 can be guided to the vent device 224 via the rib 233 located at the bottom of the cell array 100 and quickly discharged. The gas can be prevented from spreading laterally from the inside of the battery pack 10 by the partition wall 223 and the rib 233, and the gas can be prevented from spreading upward from the inside of the battery pack 10 by the cell array 100.

[0049] In this manner, in the battery pack 10 according to an embodiment of the present invention, when a thermal event occurs in a certain battery cell 110 and high-temperature gas or flames are generated, the gas can be discharged to the outside of the pack case 200 through the vent device 224 in a specific direction, not in all directions, and other battery cells 110 can be prevented from being thermally damaged as much as possible during the process of discharging the gas to the outside of the pack case 200. In addition, when gas is generally discharged from a battery cell, fragments of an electrode plate or active material inside the battery cell may be discharged to the outside in a state of being heated to a high temperature, and such high-temperature particles may appear in the form of sparks, etc. In the battery pack 10 according to an embodiment of the present invention, even if high-temperature particles are discharged from the battery cell 110, the high-temperature particles do not easily escape to the outside of the battery pack 10 immediately, and the high-temperature particles are sufficiently cooled down while being guided to the vent device 224 through the space between the ribs 233, so that such high-temperature particles can be prevented from acting as an ignition source outside the battery pack 10.

[0050] In a conventional battery pack, the vent gas diffuses in all directions from inside the battery pack and is then discharged upward, but according to the present embodiment, the vent gas is quickly guided from below the cell array 100 toward the vent device 224, making it difficult for the vent gas to diffuse in all directions from inside the battery pack 10, and the final discharge direction may not be toward the top of the battery pack 10. If the gas generated inside the battery pack is discharged in multiple directions instead of in one direction, the vent gas cannot be easily discharged to the outside of the battery pack, the time required for discharging the vent gas increases, and the safety of the battery pack may be significantly reduced.

[0051] According to one embodiment of the present invention, a vent path using the ribs 233 and the vent device 224 is formed at the bottom of the cell array 100, so that the vent gas can be more efficiently discharged in a targeted direction, for example, in the direction where the vent device 224 is formed.

[0052] According to the above embodiment, when high-temperature gas, flame, etc. are discharged from the battery cell 110 in a situation such as thermal runaway, the discharged gas, flame, etc. can be prevented from moving toward the upper side. In particular, when a passenger is located on the upper side of the battery pack 10, such as in an electric vehicle, according to the above embodiment, the gas, flame, etc. can be prevented or delayed from moving toward the passenger. In particular, according to one embodiment of the present invention, directional venting is performed on the lower side and the lateral side of the battery pack 10, thereby improving the safety of users such as passengers located on the upper side.

[0053] In particular, due to the special structure and arrangement of the ribs 233, when high-temperature gas or flame is generated, it has a remarkable effect of guiding the gas or flame toward the vent device 224. Hereinafter, the configuration of the pack case 200 including the ribs 233 will be described in more detail with reference to Figures 3 and 4 in addition to Figures 1 and 2.

[0054] 3 is a cross-sectional view of the battery pack taken along line III-III' in FIG. 1, and FIG. 4 is an enlarged view of a portion A in FIG.

[0055] As shown in FIGS. 1 to 4, a pack case 200 included in a battery pack 10 according to an embodiment of the present invention is formed in a shape with upper and lower portions open, and may include a case frame 220 for accommodating the cell array 100.

[0056] The pack case 200 may include a bottom cover 230 that covers a lower portion of the case frame 220 and is coupled to the case frame 220. The bottom cover 230 may include a base 232 that supports a lower portion of the cell array 100. The base 232 may be formed in a substantially rectangular plate shape. In addition, the bottom cover 230 may be extrusion manufactured such that the ribs 233 are integrally formed with the bottom cover 230. A detailed description of a manufacturing method of the bottom cover 230 will be given later.

[0057] The case frame 220 may be provided to form a rectangular wall along the outer periphery of the rectangular plate-shaped base 232. For example, in the embodiment of FIG. 2, the case frame 220 may include walls in a +X direction, a -Y direction, a -X direction, and a +Y direction.

[0058] Meanwhile, the pack case 200 may include a top cover 210 that covers an upper portion of the case frame 220 and is provided to be connectable to the case frame 220. The top cover 210 may be connected to an upper portion of the case frame 220, and the bottom cover 230 may be connected to a lower portion of the case frame 220 to form the pack case 200 in which the cell array 100 is accommodated. A plurality of the cell arrays 100 may be provided in the battery pack 10, and each of the cell arrays 100 may be separated by the partition wall 223 and placed on the bottom cover 230. The top cover 210 may be provided to be relatively in close contact with an upper surface of the cell array 100, so that unnecessary space may not be formed between the top cover 210 and the cell array 100.

[0059] In particular, the rib 233 according to the present embodiment may be provided to make surface contact with the lower surface of the cell array 100. That is, the lower surface of the cell array 100 may be supported by contacting the upper end surface of the rib 233. Since the surface contact is made rather than a point or line contact, a relatively large contact area is ensured, and the surface contact portion functions as a kind of barrier to prevent gas discharged from the battery cells 110 included in the cell array 100 from spreading in all directions. As a result, the vent gas can be guided to be discharged in a predetermined direction, i.e., to the lower part of the pack case 200, thereby ensuring safety.

[0060] At this time, the rib 233 may be adhesively fixed to a lower surface of the cell array 100. The rib 233 and the cell array 100 may be adhered to each other by a structural adhesive or the like, so that the connection and fixing structure may be further strengthened. The ribs 233 may be provided in a plurality on the bottom cover 230, and may be spaced apart from each other along one direction of the bottom cover 230. In the present embodiment, the ribs 233 are spaced apart from each other along the Y direction. The number and thickness of the ribs 233 may be changed according to the required rigidity and the designer's intention.

[0061] As a result, at least one vent flow path S through which the gas flows is defined by the plurality of ribs 233 spaced apart from one another, and the vent flow path S may be provided to communicate with the vent device 224. The vent flow path S may be defined as a space between two adjacent ribs 233, and a predetermined space through which gas flows may be provided below the cell array 100.

[0062] In this manner, by providing the rib 233 under the cell array 100, the inside of the pack case 200 can be partitioned into a space in which the cell array 100 is disposed and a space through which the vent gas moves. In addition, the rib 233 separates the space through which the gas flows, i.e., the vent passage S, into a plurality of regions, thereby diversifying the gas exhaust paths and increasing the total volume of the exhaust paths. Therefore, the vent passage S formed in the battery pack 10 according to an embodiment of the present invention can be effective in smoothly exhausting the vent gas to the outside of the battery pack 10 even when a large amount of vent gas is generated.

[0063] In addition, the vent flow passages S may be configured to be individually connected to a plurality of battery cells 110 that may be arranged in a row in the cell array 100. In this way, the ribs 233 can prevent gas discharged from any battery cell 110 from moving to other vent flow passages S.

[0064] Each battery cell 110 may be disposed in a bottom cover 230 as shown in Figs. 3 and 4. When the cell array 100 includes a module housing 120, the module housing 120 may have a framework for accommodating and supporting the battery cells 110, and may have cell vent holes 121 aligned at the bottom of the battery cells 110. For example, if a fire problem occurs due to a short circuit or overcharging of the battery cells 110, flames, high-temperature particles, and vent gas may be generated from the battery cells 110. At this time, the cell vent holes 121 may be provided to communicate with the vent flow path S, and the gas may be discharged from the inside of the cell array 100 to the outside, i.e., the vent flow path S, through the cell vent holes 121.

[0065] A packing member (not shown) may be attached to the cell vent hole 121. The packing member normally seals the cell vent hole 121 to prevent foreign matter from entering the module housing 120 from the outside. The packing member may be made of a material that bursts above a certain pressure or melts when heated, for example, a plastic material. That is, when an internal fire occurs in the cell array 100, the packing member, which is made of a plastic material, disappears due to the pressure or heat of the exhausted gas, and the cell vent hole 121 opens.

[0066] FIG. 5 is a diagram for explaining the direction of gas discharge during venting of a battery cell in the battery pack of FIG. 1, and FIG. 6 is an enlarged view of a vent device included in the battery pack of FIG.

[0067] 5, the vent device 224 may be provided on both sides of the case frame 220. In FIG. 5, the vent device 224 is provided on a wall in the Y direction, but may be provided on a wall in the X direction. Since the vent device 224 is provided on both sides of the case frame 220, when an abnormal situation occurs in the battery cell 110, high-temperature gas and flames can be discharged in both directions of the pack case 200, making it easier to discharge the gas and the like to the outside of the pack case 200.

[0068] At this time, the rib 233 may extend in a direction in which the vent device 224 is located. Such a structure of the rib 233 may guide the high-temperature gas or flame toward the vent device 224 so that the high-temperature gas or flame is discharged through the vent device 224. In addition, in an embodiment, the rib 233 may extend in an extension direction of the partition wall 223. This makes it possible to prevent the vent flow path S defined by the rib 233 from being blocked by the partition wall 223.

[0069] Also, the vent device 224 may be provided corresponding to each of the plurality of cell arrays 100. That is, the plurality of cell arrays 100 may be partitioned by the partition wall 223, and the vent device 224 may be provided in each of the regions in which the cell arrays 100 are arranged, partitioned by the partition wall 223. Therefore, even if a thermal event occurs in any cell array 100, it is possible to prevent gas or the like from moving to other adjacent cell arrays 100 and causing a chain reaction explosion.

[0070] 6, the case frame 220 may include a side frame 221 in which the vent device 224 is provided, and a recess 222 in which a part of the side frame 221 is recessed inward to accommodate the vent device 224. The recess 222 prevents the vent device 224 from being exposed to the outside of the pack case 200.

[0071] The vent device 224 may be composed of an external vent hole 224a formed by perforating a portion of the outer surface of the side frame 221, and a vent valve 224b for selectively opening and closing the external vent hole 224a.

[0072] 5 again, the case frame 220 may include a gas inlet 225 provided between the vent passage S and the vent device 224, through which the gas can pass. A plurality of gas inlets 225 may be provided, and the gas inlets 225 may be formed on both sides of the case frame 220, similar to the vent device 224. That is, the gas inlet 225 may be provided to communicate with both sides of the vent passage S. In this case, the gas inlet 225 may be provided on an inner surface of the case frame 220, which is a surface to which the vent passage S faces, and the vent device 224 may be provided on an outer surface of the case frame 220. A detailed shape, structure, etc. of the gas inlet 225 will be described later.

[0073] The case frame 220 may include a side gas channel C connected to the gas inlet 225 and the vent device 224 so that the gas flows therethrough. That is, the case frame 220 may include a side gas channel C, which is a space through which the gas flows, inside the side frame 221. The side gas channel C may be formed along the extending direction of the case frame 220. As shown in FIG. 5, when the case frame 220 is configured with a rectangular wall, the side gas channel C may be formed only in the wall in which the vent device 224 is provided.

[0074] Regarding the direction of gas discharge in the event that high-temperature gas or a flame occurs in any of the battery cells 110, the gas flows from the cell vent hole 121 into the vent passage S surrounded by the rib 233, and the gas flowing through the vent passage S can flow into the side gas channel C through the gas inlet 225 provided on both sides. Then, the gas can be discharged to the outside of the pack case 200 through the vent device 224. This has the effect of more efficiently guiding high-temperature gas or a flame toward the vent device 224 when an abnormality occurs in the battery cell 110.

[0075] FIG. 7 is an enlarged view of a gas inlet included in the case frame of the battery pack of FIG.

[0076] The structure of the gas inlet 225 will be described in detail. Referring to Fig. 7, the gas inlet 225 included in the case frame 220 of the battery pack 10 according to an embodiment of the present invention may be provided independently for each of the vent passages S. In other words, the gas inlet 225 may be provided to correspond one-to-one with the plurality of vent passages S. As a result, the gas generated from any one of the battery cells 110 moves only along the vent passage S connected to the any one of the battery cells 110, and the possibility that the gas propagates to other vent passages S is extremely low due to the ribs 233 that define the vent passages S.

[0077] According to such a configuration of the gas inlet 225, gas or flame generated from any battery cell 110 may move along each of the gas inlets 225 provided in the case frame 220 and be discharged to the outside of the battery pack 10 through the vent device 224. At this time, the gas inlet 225 may be formed in a rectangular shape such that the widthwise length L of the gas inlet 225 corresponds to the interval D between the ribs 233. As a result, a larger amount of gas may flow into the side gas channel C and be discharged to the outside of the battery pack 10 more quickly than in the case where the gas inlet 225 is configured as a small-diameter circular hole.

[0078] FIG. 8 is a diagram for explaining another embodiment of the gas inlet of the battery pack.

[0079] The same reference numerals as those in the above-described embodiment denote the same components, and duplicated explanations of the same components will be omitted. The following description will focus on the differences from the above-described embodiment.

[0080] The gas inlet 225' according to the other embodiment is provided integrally with the gas inlet 225 according to the above embodiment, whereas the gas inlet 225 according to the above embodiment is provided individually for each vent passage S. That is, the gas flowing through the plurality of vent passages S may be provided to the gas inlet 225'. The gas inlet 225' may be provided for each cell array 100 provided in the region between the partition walls 223, and may be formed long along both side surfaces of the case frame 220, i.e., along the Y direction. As a result, a larger amount of gas may flow into the side gas channel C than the gas inlet 225 of the above embodiment, and may be discharged to the outside of the battery pack 10 more quickly.

[0081] 9 is a diagram for explaining a method for manufacturing a bottom cover included in the battery pack of FIG. 1, and FIG. 10 is a diagram for explaining a method for manufacturing a pack case included in the battery pack of FIG.

[0082] The bottom cover 230 may be extruded in one step. Alternatively, as shown in Fig. 9, the bottom cover 230 may include a plurality of bottom plates 231a-231d joined to each other by friction stir welding. In other words, the plurality of bottom plates 231a-231d may be extruded first, and then the sides of the plurality of bottom plates 231a-231d may be abutted against each other to form a single bottom cover 230 by friction stir welding.

[0083] The bottom cover 230 may be extrusion manufactured so that the rib 233 is integrally formed with the bottom cover 230. As the bottom cover 230 is extrusion manufactured, the rib 233 may be formed to extend in one direction (X direction or Y direction) along the extrusion direction. Since the rib 233 is integrally formed with the bottom cover 230, a process of bonding the rib 233 to the bottom cover 230 is not required, and no defects are generated at the bonding portion, so that the possibility of the gas propagating to other vent flow paths S can be further reduced.

[0084] 10, the case frame 220 and the bottom cover 230 may be joined by friction stir welding. Specifically, the bottom cover 230 may be placed on the case frame 220 of the pack case 200, and the bottom cover 230 and the case frame 220 may be overlapped and friction stir welded to form the pack case 200. As a result, gas flowing through the vent passage S may be prevented from leaking to the outside of the pack case 200, and may be discharged to the outside only through the vent device 224.

[0085] FIG. 11 is a perspective view of a vehicle including the battery pack of FIG.

[0086] Meanwhile, an embodiment of the present invention may provide an automobile 20 including the battery pack 10 according to the above-described embodiment. That is, the battery pack 10 according to an embodiment of the present invention may be applied to automobiles such as electric vehicles and hybrid vehicles. For example, the battery pack 10 may be installed in a body frame or a trunk space under a vehicle seat.

[0087] According to the various embodiments as described above, it is possible to provide a battery pack 10 and an automobile 20 including the battery pack 10, which can efficiently guide high-temperature gas and flames generated from the battery cell 110 toward the vent device 224 and quickly discharge them to the outside when an abnormal condition occurs in the battery cell 110.

[0088] For reference, the battery pack 10 according to an embodiment of the present invention can be applied to an energy storage system (ESS) and various electric devices other than an automobile.

[0089] Meanwhile, in this specification, terms indicating directions such as up, down, left, right, front, and back are used, but these terms are merely for convenience of explanation, and it will be obvious to those skilled in the art of the present invention that they may change depending on the position of the object of interest, the position of the observer, etc.

[0090] Although the present invention has been described above using limited embodiments and drawings, the present invention is not limited thereto, and it goes without saying that various modifications and variations can be made by a person having ordinary knowledge in the technical field to which the present invention pertains within the scope of the technical concept of the present invention and the scope of the claims. [Explanation of symbols]

[0091] 10 Battery Pack 100 Cell Array 110 Battery Cell 200 pack case 224 Venting Device 233 Rib

Claims

1. a cell array including a plurality of battery cells; a pack case that houses the cell array; Including, The pack case includes: a vent device provided to exhaust gas generated from the cell array to the outside of the pack case; a rib provided under the cell array for guiding the gas to the vent device; Including the battery pack.

2. The battery pack according to claim 1 , wherein the rib is provided in surface contact with a lower surface of the cell array.

3. The battery pack according to claim 2 , wherein the rib is adhesively fixed to a lower surface of the cell array.

4. The pack case includes: a case frame having an open upper and lower portion and configured to accommodate the cell array; a bottom cover covering a lower portion of the case frame and coupled to the case frame; 10. The battery pack of claim 1 , comprising:

5. The battery pack according to claim 4 , wherein the ribs are provided on the bottom cover in a plurality of portions spaced apart from each other along one direction of the bottom cover.

6. the rib defines at least one vent passage through which the gas flows; The battery pack according to claim 5 , wherein the vent passage is provided in communication with the vent device.

7. The battery pack of claim 4 , wherein the bottom cover is extruded such that the ribs are integrally formed with the bottom cover.

8. The vent device is provided on one side of the case frame, The case frame includes: The battery pack according to claim 6 , further comprising a gas inlet provided between the vent passage and the vent device, through which the gas can pass.

9. The battery pack according to claim 8 , wherein the gas inlet is provided independently for each of the vent passages.

10. 10. The battery pack according to claim 9, wherein the gas inlet is formed in a rectangular shape such that a width direction length of the gas inlet corresponds to a distance between the ribs.

11. The battery pack according to claim 9 , wherein the gas inlets are integrally formed.

12. The case frame includes:

9. The battery pack of claim 8, further comprising a side gas channel connected with the gas inlet and the vent device for allowing the gas to flow therethrough.

13. The battery pack according to claim 12 , wherein the side gas channel is formed along an extension direction of the case frame.

14. The battery pack of claim 4 , wherein the bottom cover includes a plurality of bottom plates joined together by friction stir welding.

15. The battery pack according to claim 4 , wherein the case frame and the bottom cover are joined by friction stir welding.

16. The battery pack according to claim 8 , wherein the vent device is provided on both sides of the case frame.

17. The battery pack according to claim 16 , wherein the rib extends in a direction in which the vent device is located.

18. The battery pack of claim 16 , wherein the case frame includes an indentation for accommodating the vent device.

19. the pack case accommodates a plurality of the cell arrays, The battery pack according to claim 4 , wherein the case frame further includes a partition wall that separates the plurality of cell arrays.

20. The battery pack according to claim 19 , wherein the vent device is provided corresponding to each of a plurality of the cell arrays.

21. 21. A motor vehicle comprising a battery pack according to any one of claims 1 to 20.

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