Battery pack and vehicle including same

Abstract

The present invention relates to a battery pack mounted on a lower portion of a chassis, the battery pack comprising: a plurality of battery cells; a pack case in which the plurality of battery cells are accommodated and of which an upper portion is configured to be couplable to the chassis; and a fixing member which is interposed between the pack case and the chassis and is configured to suppress deformation of the pack case.

Description

Battery pack and vehicle including same

[0001] The present invention relates to a battery pack, and more particularly, to a battery pack with enhanced safety and a vehicle including the same.

[0002] This application claims priority to Korean Patent Application No. 10-2024-0042026, filed on March 27, 2024, and all contents disclosed in the specification and drawings of the said application are incorporated herein by reference.

[0003] Secondary batteries, which boast high electrical properties such as high energy density and easy applicability across a wide range of product categories, are widely used not only in portable devices but also in electric vehicles (EVs) and hybrid electric vehicles (HEVs) powered by electrical power sources. These batteries are attracting attention as a new energy source for environmental friendliness and energy efficiency, not only because they can dramatically reduce fossil fuel use, but also because they produce no byproducts from energy use.

[0004] Commonly used secondary batteries today include lithium-ion batteries, lithium polymer batteries, nickel-cadmium batteries, nickel-metal hydride batteries, and nickel-zinc batteries. When high output voltage is required, multiple battery cells are connected in series to form a battery module or battery pack. Furthermore, to increase charge / discharge capacity, multiple battery cells are connected in parallel to form a battery module or pack. Therefore, the number of battery cells included in a battery module or pack can vary depending on the required output voltage or charge / discharge capacity.

[0005] Meanwhile, since battery cells undergo chemical reactions during charging and discharging, their performance can deteriorate if used in environments above their optimal temperature. Furthermore, if thermal control fails to maintain optimal temperatures, there's a constant risk of unexpected fire or explosion. Therefore, if a thermal event, such as thermal runaway, occurs within the battery pack, the high-temperature gases or flames emitted from the battery cells contained within could spread to adjacent battery modules, potentially triggering a chain reaction of battery module explosions, posing a significant risk.

[0006] A battery module is composed of battery cells housed in a module frame, while a battery pack houses these battery modules in a pack case. Conventionally, high-temperature gases and flames are discharged through venting holes provided at the top of the module frame, and are then discharged outside the pack case through the space between the pack case and the battery modules.

[0007] However, as the shape of the pack case is deformed by heat such as high-temperature gas or flame, the gap between the pack case and the battery module is not maintained, making it difficult to secure a path for high-temperature gas or flame to be discharged to the outside of the pack case. In particular, if the pack lead constituting the upper surface of the pack case is thermally deformed and sags downward, a problem may arise in which the venting path provided at the upper part of the battery module is blocked. Accordingly, the possibility of heat transfer to the adjacent battery module and explosion due to increased internal pressure may increase.

[0008] Therefore, when a thermal runaway occurs in a battery module, there is a need to develop a structure that can prevent heat accumulation inside the battery pack by securing a path for high-temperature gas or flames generated inside the battery module to be discharged to the outside of the battery pack.

[0009] Therefore, the problem to be solved by the present invention is to provide a battery pack with improved safety and reliability by smoothly discharging gas or flame generated inside the battery module to the outside of the battery pack when thermal runaway of the battery module occurs.

[0010] In addition, another problem that the present invention seeks to solve is to provide a vehicle including such a battery pack.

[0011] However, the problems to be solved by the present invention are not limited to the problems described above, and other problems not mentioned can be clearly understood by those skilled in the art from the description of the invention described below.

[0012] In order to solve the above problem, the present invention comprises a battery pack mounted on the lower part of a chassis, comprising: a plurality of battery cells; a pack case configured to accommodate the plurality of battery cells and configured such that an upper portion thereof can be coupled to the chassis; and a fixing member interposed between the pack case and the chassis and configured to suppress deformation of the pack case.

[0013] The pack case may include a case body having an open upper surface configured to accommodate the plurality of battery cells, and a pack lid configured to cover the open upper surface of the case body.

[0014] A venting space is formed between the battery cell and the pack case, in which a venting gas generated from the battery cell is configured to flow, and the fixing member can be configured to maintain the height of the venting space at a predetermined distance or more.

[0015] The module case may further include a plurality of battery cells grouped together and a venting hole formed on the upper surface to discharge venting gas generated internally to the outside.

[0016] At least one of the above fixing members may be provided at a position corresponding to the central portion of the module case.

[0017] The above-mentioned fixing member may include a first coupling portion configured to penetrate the chassis from the outside, and a second coupling portion configured to be coupled to the first coupling portion from the inside of the pack case.

[0018] The above fixing member may include a compression member provided between the pack case and the chassis and configured to at least partially surround the first coupling portion.

[0019] The above fixing member is provided in multiple pieces, and at least some of the fixing members may be configured such that the elastic modulus of the compression portion is different from each other.

[0020] The above fixing member may include an insulating member configured to at least partially surround the compression member.

[0021] The above-mentioned fixed member may be configured such that one end can be fixed to the chassis, and the other end can be fixed to the pack case and configured such that it can move in a vertical direction.

[0022] The above-mentioned fixing member may be provided as a spring configured such that one end and the other end are connected to the pack case and the chassis, respectively.

[0023] And, the present invention provides an automobile characterized by including a battery pack according to the present invention.

[0024] In addition, a vehicle according to one embodiment of the present invention may include a battery pack having a chassis; a plurality of battery cells; and a pack case having an upper portion coupled to the chassis and configured to accommodate the plurality of battery cells; and a fixing member interposed between the pack case and the chassis and configured to suppress deformation of the pack case.

[0025] According to one aspect of the present invention, by providing a fixing member, thermal deformation of the pack lead and the occurrence of a negative gap can be suppressed. Accordingly, according to this aspect of the present invention, a path can be secured for high-temperature gases or flames generated in the battery module during an abnormal condition to be discharged to the outside of the battery pack. This effectively prevents or delays the propagation of thermal runaway between battery modules, thereby ensuring the safety and reliability of the battery pack.

[0026] In addition, according to another aspect of the present invention, it is possible to prevent high-temperature gases or flames generated in a battery cell in an abnormal situation of the battery module from flowing back into the battery module.

[0027] In addition, according to another aspect of the present invention, events resulting from thermal runaway of a device equipped with a battery pack, such as fire or explosion, can be prevented or delayed.

[0028] In addition, the present invention may have various other effects, which will be described in each embodiment configuration, or the description of effects that can be easily inferred by those skilled in the art will be omitted.

[0029] The following drawings attached to this specification illustrate preferred embodiments of the present invention, and together with the detailed description of the invention described below, serve to further understand the technical idea of ​​the present invention, and therefore, the present invention should not be interpreted as being limited to matters described in such drawings.

[0030] FIG. 1 is a perspective view of a battery pack according to one embodiment of the present invention.

[0031] Figure 2 is an exploded perspective view of a battery pack according to one embodiment of the present invention.

[0032] Fig. 3 is a cross-sectional view of a battery pack according to one embodiment of the present invention. For example, Fig. 3 may be a drawing showing cross-section I-I' of Fig. 1.

[0033] Figure 4 is an enlarged view of part A of Figure 3.

[0034] FIG. 5 is a comparative example, illustrating deformation of a pack lead when a fixing member included in a battery pack according to one embodiment of the present invention is not provided.

[0035] FIG. 6 is a drawing for explaining the coupling position of a fixing member included in a battery pack according to one embodiment of the present invention.

[0036] FIG. 7 is a perspective view of a combination of a fixing member included in a battery pack according to one embodiment of the present invention.

[0037] FIG. 8 is an exploded perspective view of a fixing member included in a battery pack according to one embodiment of the present invention.

[0038] FIG. 9 is a drawing showing that deformation of a pack lead is suppressed when a fixing member included in a battery pack according to one embodiment of the present invention is provided.

[0039] FIG. 10 is a drawing for explaining a fixing member included in a battery pack according to another embodiment of the present invention.

[0040] FIG. 11 and FIG. 12 are drawings showing that deformation of a pack lead is suppressed when a fixing member included in a battery pack according to another embodiment of the present invention is provided.

[0041] FIG. 13 is a schematic perspective view of a vehicle including a battery pack according to one embodiment of the present invention.

[0042] Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the attached drawings. Prior to this, it should be noted that the terms and words used in this specification and claims should not be construed as limited to their conventional or dictionary meanings. Based on the principle that the inventor can appropriately define the concepts of terms to best explain his or her invention, they should be interpreted in a way that aligns with the technical spirit of the present invention.

[0043] Accordingly, the embodiments described in this specification and the configurations illustrated in the drawings are merely the most preferred embodiments of the present invention and do not represent all of the technical ideas of the present invention. Therefore, it should be understood that there may be various equivalents and modified examples that can replace them at the time of filing this application.

[0044] Furthermore, the present invention includes various embodiments. For each embodiment, redundant descriptions of substantially identical or similar components will be omitted, and the differences will be described.

[0045] Meanwhile, in the present invention, terms indicating directions such as up, down, left, right, front, and back may be used, but it is obvious to those skilled in the art that these terms are only for convenience of explanation and may vary depending on the location of the target object or the location of the observer.

[0046] For example, in an embodiment of the present invention, the X-axis direction shown in the drawing may mean a left-right direction, the Y-axis direction may mean a front-back direction perpendicular to the X-axis direction on a horizontal plane (XY plane), and the Z-axis direction may mean an up-down direction (vertical direction) perpendicular to both the X-axis direction and the Y-axis direction.

[0047]

[0048] FIG. 1 is a perspective view of a battery pack according to an embodiment of the present invention, FIG. 2 is an exploded perspective view of a battery pack according to an embodiment of the present invention, and FIG. 3 is a cross-sectional view of a battery pack according to an embodiment of the present invention. For example, FIG. 3 may be a drawing showing a cross-section taken along line I-I' of FIG. 1. In addition, FIG. 4 is an enlarged view of part A of FIG. 3. In addition, FIG. 5 is a comparative example, which illustrates deformation of a pack lead when a fixing member included in a battery pack according to an embodiment of the present invention is not provided.

[0049] A battery pack (1) according to one embodiment of the present invention may be configured to be mounted on the lower portion of a chassis (C). The chassis (C) may be provided on the exterior of the battery pack (1). For example, the chassis (C) may be a frame on which the battery pack (1) is mounted inside an automobile or the like.

[0050] Also, referring to FIGS. 1 to 4, a battery pack (1) according to one embodiment of the present invention includes a battery cell (100), a pack case (200), and a fixing member (300).

[0051] First, referring primarily to FIG. 2, a plurality of battery cells (100) may be included. Although not illustrated in the drawing, the plurality of battery cells (100) may include an electrode assembly, a cell case accommodating the electrode assembly, and electrode leads connected to the electrode assembly and extending outward from the cell case to function as electrode terminals. In this case, the plurality of battery cells (100) may be electrically connected to each other.

[0052] The battery cell (100) may be a pouch-type secondary battery. The cell case of such a pouch-type secondary battery may be configured in a pouch shape in which a metal layer made of aluminum is interposed between polymer layers.

[0053] A plurality of battery cells (100) can be stacked and arranged along the front-back direction (Y-axis direction) while standing in the vertical direction (Z-axis direction), as illustrated in FIG. 2.

[0054] Meanwhile, the present invention is not limited by the specific type or shape of the battery cell (100), and various battery cells (100) known at the time of filing of the present invention may be employed to construct the battery pack (1) of the present invention. In this embodiment, a pouch-type secondary battery having a high energy density and easy stacking is targeted as shown in the drawing, but it goes without saying that a cylindrical or square secondary battery may be applied as the battery cell (100).

[0055] The pack case (200) may be configured to accommodate a plurality of battery cells (100). The pack case (200) may be provided in a box shape including a plurality of frames. The pack case (200) may be made of a material that can ensure mechanical rigidity, such as a metal such as steel or SUS, or a plastic, or may include such a material, in order to safely protect the battery cells (100) accommodated therein.

[0056] This pack case (200) can be configured to be coupled to the chassis (C). In particular, the pack case (200) can be configured such that the upper portion thereof can be coupled to the chassis (C). That is, the pack case (200) can be provided at the lower portion of the chassis (C) and configured to be coupled to the lower portion of the chassis (C).

[0057] Meanwhile, when thermal runaway occurs in any battery module (10) provided inside the battery pack (1), the shape of the pack case (200) may be deformed due to the pressure and / or high heat of the venting gas discharged from the battery cell (100). For example, as illustrated in FIG. 5, which is a comparative example, the upper surface of the pack case (200) may be lowered, resulting in a negative gap.

[0058] At this time, as illustrated in FIGS. 3 and 4, a battery pack (1) according to one embodiment of the present invention may be provided with a fixing member (300). The fixing member (300) may be interposed between the pack case (200) and the chassis (C). The fixing member (300) may be configured to connect the pack case (200) and the chassis (C).

[0059] This fixing member (300) may be configured to suppress deformation of the pack case (200). In particular, the fixing member (300) may be configured to suppress the upper surface of the pack case (200) from sagging downward by a certain level or more by holding the upper surface of the pack case (200) when the upper surface of the pack case (200) is about to sag downward.

[0060] According to the above-described embodiment of the present invention, the pack case (200) can be prevented from being bent or deformed by pressure and / or heat, such as a venting gas, by the fixing member (300). In particular, the upper surface of the pack case (200) can be prevented from being excessively sagging due to thermal deformation.

[0061] Accordingly, according to the above-described embodiment of the present invention, a path can be secured for high-temperature gases or flames generated in the battery cell (100) to be discharged to the outside of the battery pack (1) in the event of an abnormal situation in the battery module (10). As a result, the propagation of thermal runaway within the battery pack can be effectively prevented or delayed, thereby ensuring the safety and reliability of the battery pack (1).

[0062] In addition, according to the above-described embodiment of the present invention, high-temperature gas or flames generated in the battery cell (100) are quickly discharged to the outside of the battery pack (1), thereby preventing high-temperature gas or flames from flowing back into the battery cell (100).

[0063]

[0064] Meanwhile, referring mainly to FIGS. 1 and 2, the pack case (200) may include a case body (210) and a pack lid (220).

[0065] The case body (210) may be configured to have an open upper surface so that a plurality of battery cells (100) can be installed therein. More specifically, the case body (210) may include a base frame (211) and a side frame (212).

[0066] The above base frame (211) may be configured to accommodate a plurality of battery modules (10). The base frame (211) may form the lower surface of the pack case (200) and may be provided in the shape of a square plate. In addition, the base frame (211) may be provided with a flat upper surface so that the module case (120) may be stably accommodated.

[0067] The side frame (212) may extend upward from each corner of the base frame (211). The side frame (212) may be provided with a plurality of unit walls to surround a plurality of battery modules (10). More specifically, the plurality of side frames (220) may be provided with a right wall located at the +X direction side end of the base frame (210), a rear wall located at the +Y direction side end, a left wall located at the -X direction side end, and a front wall located at the -Y direction side end, respectively, to form a side surface of the pack case (200).

[0068] Additionally, the pack case (200) may include a cross beam (213). The cross beam (213) may be configured to partition the internal space of the pack case (200). The cross beam (213) may be configured to partition and group a plurality of battery cells (100). The cross beam (213) may be configured to extend along the left-right direction and / or the front-back direction of the pack case (200).

[0069] Additionally, a plurality of cross beams (213) may be provided. The cross beam (213) may include a main beam (213a) and a sub beam (213b). The main beam (213a) and the sub beam (213b) may be arranged in a mutually perpendicular direction.

[0070] The main beam (213a) may be configured to connect at least some of the side frames (220). For example, as illustrated in FIG. 2, the main beam (213a) may be configured to extend in the front-rear direction and connect the front wall and the rear wall among the side frames (220).

[0071] The sub beam (213b) may be configured to connect the side frame (212) and the main beam (213a) to each other. For example, as illustrated in FIG. 2, the sub beam (213b) may be configured to extend in the left-right direction to connect the left wall and / or the right wall of the side frame (220) and the main beam (213a) to each other. A plurality of sub beams (213b) may be provided along the front-rear direction.

[0072] The above pack lid (220) may be configured to cover the open upper surface of the case body (210). The pack lid (220) may be provided to be coupled to the upper portion of the side frame (212) to form the upper surface of the pack case (200). At this time, the pack lid (220) may be provided to be spaced apart from the upper portion of the cross beam (213) and the battery cell (100) by a predetermined distance in the vertical direction (Z-axis direction).

[0073] Meanwhile, referring to FIG. 2, the pack case (200) may include a venting device (230). The venting device (230) may be configured to discharge gas generated from the battery cell (100) to the outside of the pack case (200).

[0074] The venting device (230) may be configured to open by the pressure of the venting gas when the venting gas is generated inside the pack case (200) and the internal pressure increases, thereby discharging the venting gas to the outside of the pack case (200).

[0075] For example, the venting device (230) may be configured to open and close depending on the internal pressure within the pack case (200). Alternatively, the venting device (230) may be configured in the form of a hole. Meanwhile, the present invention is not limited by the specific type or shape of the venting device (230), and various venting devices (230) known at the time of filing of the present invention may be employed to configure the battery pack (1) of the present invention.

[0076] Specifically, the venting device (230) may be provided on the side of the pack case (200), i.e., on the side frame (220). The venting device (230) may be provided on at least one side frame (220) among a plurality of side frames (220). In addition, the venting device (230) may be positioned between the main beam (213a) and the side frame (212). For example, as in the embodiment illustrated in FIG. 2, the venting device (230) may be positioned on the front and rear side frames (212), and may be arranged between the left and / or right side frames (212) and the main beam (213a).

[0077] A plurality of venting devices (230) may be provided. The venting devices (230) may be formed separately on two or more side frames (220), or two or more may be formed on one side frame (220).

[0078] Meanwhile, the number or location of the venting device (230) described based on the embodiment of FIG. 2 is merely an example, and it is obvious that the number or location may be changed to various other numbers or locations.

[0079]

[0080] As described above, the battery cell (100) and the pack lead (220) are spaced apart by a predetermined distance, so that venting gas or flames, etc. can move into the spaced apart space. That is, a venting space (S) can be formed in the space between the pack lead (220) and the battery cell (100). The venting space (S) can be configured to extend along the direction in which the venting device (230) is arranged.

[0081] At this time, as illustrated in FIGS. 3 and 4, the fixing member (300) may be configured to maintain the height (d) of the venting space (S) at a predetermined distance or more. Here, the height (d) of the venting space (S) refers to the length in the vertical direction (Z-axis direction) and may refer to the vertical distance from the upper surface of the battery cell (100) to the lower surface of the pack lead (220). Here, the predetermined distance may mean a distance through which venting gas or flame, etc. can move smoothly when a thermal event occurs. For example, it is preferable that the height (d) of the venting space (S) be maintained at a distance greater than the distance between the undeformed pack lead (220) and the battery cell (100) or the battery module (10) described later.

[0082] Meanwhile, when the battery pack (1) is combined with the chassis (C), the chassis (C) may be combined with the edge of the pack lead (220), i.e., the side frame (212). At this time, as a strong restraining force is applied to the edge of the pack lead (220), if thermal runaway occurs inside the pack case (200), the center of the pack lead (220) is more likely to be thermally deformed by the pressure and / or heat of the venting gas.

[0083] In particular, if the fixing member (300) is not provided as illustrated in FIG. 5, which is a comparative example, there is no structure between the top of the pack lead (220) and the chassis (C), and thus the height (d') of the venting space (S) may become very narrow as the pack lead (220) sags downward, which may cause a problem. As a result, since the venting path is not sufficiently secured, venting gas or flames, etc. may not be discharged to the outside of the battery pack (1), which may cause thermal runaway (see the bold arrow in FIG. 5).

[0084] However, according to one embodiment of the present invention, since the fixing member (300) firmly holds the upper portion of the pack lead (220), the pack lead (220) can be prevented from sagging due to pressure and / or heat such as venting gas, as shown in FIG. 5.

[0085] Accordingly, according to the above-described embodiment of the present invention, the height (d) of the venting space (S) can be maintained at a certain distance or more, so that venting gas or flames, etc. can be smoothly discharged to the outside of the battery pack (1) through the venting space (S), thereby suppressing or preventing thermal runaway within the battery pack (1). As a result, the safety and reliability of the battery pack (1) can be guaranteed.

[0086]

[0087] FIG. 6 is a drawing for explaining the coupling position of a fixing member included in a battery pack according to one embodiment of the present invention.

[0088] Meanwhile, referring to FIG. 6, a plurality of battery cells (100) may be modularized into one or more battery modules (10). That is, the battery pack (1) according to the present invention includes a plurality of battery modules (10), and the plurality of battery cells (100) included in the battery pack (1) may be divided and included in a plurality of battery modules (10). At this time, the plurality of battery cells (100) included in the battery module (10) may be electrically connected to each other.

[0089] In particular, the battery pack (1) according to the present invention may include a module case (11). The module case (11) may be configured to have an empty space formed therein and accommodate at least some of a plurality of battery cells (100) in the internal space. In particular, the module case (11) may be configured to accommodate the battery cells (100). That is, the module case (11) groups a plurality of battery cells (100) into a plurality of battery modules (10) and may serve as a boundary that physically limits the internal space of each battery module (10).

[0090] Additionally, although not shown in the drawing, the battery module (10) may include a busbar assembly and / or module terminals electrically connected to a plurality of battery cells (100) housed therein.

[0091] These plurality of battery modules (10) may be arranged adjacently in the front-back direction and / or left-right direction along a number of rows. For example, as illustrated in FIG. 6, the plurality of battery modules (10) may be arranged in four rows along the front-back direction (Y-axis direction) and in two rows along the left-right direction (X-axis direction).

[0092] Meanwhile, the battery module (10) may include a venting hole (H). The venting hole (H) may be configured to allow gas generated from a battery cell (100) housed inside the module case (11) to be discharged to the outside of the module case (11).

[0093] Specifically, a venting hole (H) may be provided in the module case (11) to enable directional venting in a specific direction. The venting hole (H) may be provided on at least one side of the module case (11). FIG. 8 illustrates an embodiment in which the venting hole (H) is provided on the upper surface of the module case (11). Accordingly, the venting gas can be directly discharged into the venting space (S) provided on the upper portion of the module case (11). In addition, the venting gas or flame flowing inside the venting space (S) can be discharged along the front-rear direction of the pack case (200) through the venting device (230).

[0094] Meanwhile, the number and location of the venting holes (H) described based on the embodiment of Fig. 6 are merely examples, and can be changed to other numbers or locations.

[0095] The fixing member (300) may be provided in multiple units. The multiple fixing members (300) may be arranged to be spaced apart from each other. That is, the fixing members (300) may be configured in an island type. According to the above-described embodiment of the present invention, the position of the fixing member (300) can be freely set. This increases the degree of design freedom, thereby improving productivity.

[0096] Moreover, at least one fixing member (300) may be provided at a position corresponding to the center of the module case (11). In particular, the fixing member (300) may be provided between adjacent cross beams (213). In particular, the fixing member (300) may be provided between adjacent sub beams (213b). The fixing member (300) may be arranged in the front-back direction along the arrangement direction of the sub beams (213b).

[0097] When venting gas or flames are discharged from the venting hole (H), there is a high possibility that the central portion of the battery module (10) of the pack lid (220) adjacent to the central portion of the battery module (10) will be thermally deformed and sag due to the heat of the venting gas or flames. Accordingly, by providing the fixing member (300) in the central portion of the battery module (10) as in the above-described embodiment of the present invention, the venting space (S) can be secured more effectively.

[0098] At this time, the fixing member (300) may be provided on the upper side of the venting hole (H) in the vertical direction and between the venting holes (H) in the horizontal direction. According to the above-described embodiment of the present invention, since the fixing member (300) is provided between the venting holes (H), the venting gas or flame discharged from the venting hole (H) can move between the fixing members (300). Accordingly, the fixing member (300) may not impede the movement of the venting gas or flame within the venting space (S).

[0099] In addition, the fixing member (300) may not be provided on the upper portion of the main beam (213a). For example, as in the embodiment illustrated in FIG. 6, the venting space (S) is formed by being separated into left and right sides based on the main beam (213a), and the venting gas, etc. can be discharged to the outside of the pack case (200) through the venting devices (230) provided on the left and right sides. At this time, deformation of the pack lid (220) can be suppressed only in the portion where the fixing member (300) is provided.

[0100] Accordingly, according to the above-described embodiment of the present invention, when the pack lead (220) is thermally deformed and sags downward on the upper portion of the main beam (213a) where the fixing member (300) is not provided, the gap of the venting space (S) becomes very narrow, so that venting gas or flames, etc. can be suppressed from moving between the battery cells (100) or battery modules (10) beyond the cross beam (213).

[0101]

[0102] Fig. 7 is a perspective view of a fastening member included in a battery pack according to one embodiment of the present invention, and Fig. 8 is an exploded perspective view of a fastening member included in a battery pack according to one embodiment of the present invention. In addition, Fig. 9 is a drawing showing that deformation of a pack lead is suppressed when a fastening member included in a battery pack according to one embodiment of the present invention is provided.

[0103] The structure of the fixing member (300) will be described in detail with reference to FIGS. 7 and 8. Specifically, the fixing member (300) may include a first coupling portion (310) and a second coupling portion (320). The first coupling portion (310) and the second coupling portion (320) may be configured to be mutually fastened to connect the chassis (C) and the pack lead (220) to each other.

[0104] More specifically, the first coupling portion (310) may be configured to be coupled to the chassis (C). The first coupling portion (310) may be configured to penetrate the chassis (C) from the outside. The first coupling portion (310) may be configured to penetrate up to the pack lead (220). That is, the first coupling portion (310) may be configured to penetrate both the chassis (C) and the pack lead (220) from the outside of the chassis (C).

[0105] The first connecting portion (310) may be configured in a bolt shape. The first connecting portion (310) may include a protrusion (311) that protrudes outward from the chassis (C) and an extension (312) that extends from the protrusion (311) toward the inside of the chassis (C). In this case, it is preferable that the protrusion (311), which corresponds to the bolt head, be a flat head rather than a round head to secure a contact area with the chassis (C).

[0106] The second coupling portion (320) may be configured to be coupled with the first coupling portion (310). The second coupling portion (320) may be provided on the inside of the pack case (200). The second coupling portion (320) may be configured in a nut shape. That is, a tab may be formed on the chassis (C) and the pack lid (220), and the first coupling portion (310) in the shape of a bolt may be inserted therein to be fastened with the second coupling portion (320) in the shape of a nut.

[0107] Meanwhile, a screw thread (313) may be formed in the extension (312) of the first connecting portion (310). At this time, the screw thread (313) may be formed lower than the second connecting portion (320). Accordingly, the second connecting portion (320) may be configured not to move downward.

[0108] According to the above-described embodiment of the present invention, since the coupling gap between the first coupling portion (310) and the second coupling portion (320) can be maintained at a constant interval, the pack lead (220) can be suppressed from sagging downward. Accordingly, according to the above-described embodiment of the present invention, since the height (d) of the venting space (S) can be maintained at a constant interval or more, venting gas or flames, etc. can be smoothly discharged to the outside of the battery pack (1) through the venting space (S), thereby suppressing or preventing thermal runaway between battery modules (10). As a result, the safety and reliability of the battery pack (1) can be guaranteed.

[0109] In addition, as in the embodiment illustrated in FIG. 9, when thermal runaway occurs in the battery module (10), a portion of the pack lead (220) located at the upper portion of the battery module (10) may swell upward due to pressure and / or heat such as venting gas or flame (in the direction of the thick arrow in FIG. 9). At this time, according to the above-described embodiment of the present invention, since the screw line (313) of the first coupling portion (310) is located only at the lower portion of the second coupling portion (320), the pack lead (220) may be allowed to swell to a certain extent.

[0110] That is, the fixing member (300) can maintain the height (d) of the venting space (S) above a certain distance by suppressing the minus gap of the pack lead (220) as much as possible and allowing a certain level of plus gap. Thus, according to the above-described embodiment of the present invention, when thermal runaway of the battery module (10) occurs and the pack lead (220) swells upward, the venting space (S) is further secured, so that the venting gas and the like can be discharged more smoothly to the outside of the pack case (200).

[0111] In addition, according to the above-described embodiment of the present invention, the first coupling part (310) and the second coupling part (320) can be more firmly connected, and the assembling ability can be improved when manufacturing the battery pack (1).

[0112] Meanwhile, the fixing member (300) may further include a compression member (330). The compression member (330) may be configured to be compressed according to the deformation of the pack lid (220) when the pack lid (220) expands upward. At this time, the compression member (330) may be configured so that the gap between the pack case (200) and the pack lid (220) is maintained at a predetermined gap or more.

[0113] More specifically, the compression member (330) may be provided between the pack case (200) and the chassis (C). The compression member (330) may include a material having elasticity. For example, the compression member (330) may be provided with a spring or an elastic pad.

[0114] According to the above-described embodiment of the present invention, since the compression portion (330) is configured to be compressible with elasticity, the pack lead (220) can be prevented from expanding and coming into contact with the chassis (C). That is, according to the above-described embodiment of the present invention, while a certain level of upward deformation of the pack lead (220) is permitted, excessive expansion of the pack lead (220) by the compression portion (330) and coming into contact with the chassis (C) can be prevented.

[0115] Additionally, the compression member (330) may be configured to at least partially surround the first coupling member (310). That is, the first coupling member (310) may be configured to penetrate the compression member (330). According to the above-described embodiment of the present invention, the compression member (330) may be prevented from being detached when the pack lid (220) is inflated upward.

[0116] At this time, the fixing member (300) is provided in multiple pieces, and at least some of the fixing members (300) may be configured such that the elastic coefficients of the compression portion (330) are different from each other. That is, the elastic coefficients of the compression portion (330) may be configured differentially for each position where the fixing member (300) is provided. Specifically, when the elastic coefficient of the compression portion (330) is small, it can be compressed or stretched more easily than when the elastic coefficient is small. Accordingly, the elastic coefficients of the compression portions (330) of the fixing members (300) provided in positions where securing a venting space (S) is more necessary can be designed to be relatively small.

[0117] For example, the elastic modulus of the compression member (330) provided close to the venting device (230) may be configured to be smaller than the elastic modulus of the compression member (330) provided on the inside of the pack case (200). In this case, the pack lid (220) can be more easily deformed upward by the pressure of the venting gas or flame, etc., thereby securing the venting space (S).

[0118] According to the above-described embodiment of the present invention, since the elastic coefficient of the compression member (330) is configured differentially, the volume of the venting space (S) can be configured differently at each location. Accordingly, the venting direction of the venting gas or flame, etc. can be induced in a specific direction.

[0119] Meanwhile, referring to FIGS. 7 and 8, the fixing member (300) may further include an insulating member (340). The insulating member (340) may be configured to electrically insulate the compression member (330) and prevent heat conduction, etc. For this purpose, the insulating member (340) may be made of a material such as polyurethane or silicone.

[0120] This insulation (340) may be provided between the pack lid (220) and the chassis (C). The insulation (340) may be provided on the outside of the compression portion (330). The insulation (340) may be configured to at least partially surround the compression portion (330). In addition, the insulation (340) may be configured to be compressed together when the compression portion (330) is compressed due to deformation of the pack lid (220).

[0121] According to the above-described embodiment of the present invention, by providing the insulation portion (340), the compression portion (330) can be prevented from melting or disappearing due to high heat such as a flame. Accordingly, even in a situation where a flame occurs, the function of maintaining the gap between the pack lid (220) and the chassis (C) by the compression portion (330) can be secured.

[0122]

[0123] FIG. 10 is a drawing for explaining a fixing member included in a battery pack according to another embodiment of the present invention. In addition, FIGS. 11 and 12 are drawings showing that deformation of a pack lead is suppressed when a fixing member included in a battery pack according to another embodiment of the present invention is provided.

[0124] According to another embodiment of the present invention, the fixing member (300') may be configured such that one end is fixable to the chassis (C), and the other end is fixed to the pack case (200) and configured to be movable in the vertical direction. The other end of the fixing member (300') may be fixed to the pack lid (220) and may move according to the deformation of the pack lid (220). The fixing member (300') may be configured such that its vertical length, i.e., its height, changes.

[0125] Such a fixing member (300') may include a material having elasticity. For example, as in the embodiments illustrated in FIGS. 10 to 12, the fixing member (300') may be provided as a spring, one end and the other end of which are configured to be connected to the pack case (200) and the chassis (C), respectively. Accordingly, the fixing member (300') may be configured to be compressed or stretched depending on the deformation of the pack lid (220).

[0126] According to the above-described embodiment of the present invention, as in the embodiment illustrated in FIG. 11, the pack lid (220) can be suppressed from sagging downwards with only a simple structure of the fixing member (300'). Accordingly, according to the above-described embodiment of the present invention, the height (d) of the venting space (S) can be maintained at a predetermined distance or more, so that venting gas or flames, etc. can be smoothly discharged to the outside of the battery pack (1) through the venting space (S), thereby suppressing or preventing thermal runaway between battery modules (10). As a result, the safety and reliability of the battery pack (1) can be guaranteed.

[0127] In addition, according to the above-described embodiment of the present invention, as in the embodiment illustrated in FIG. 12, since the fixing member (300') is configured to be elastic and compressible, the pack lid (220) is allowed to swell upward to a certain degree, thereby further securing the venting space (S). Furthermore, according to the above-described embodiment of the present invention, while the pack lid (220) is allowed to deform upward to a certain degree, the pack lid (220) can be prevented from excessively expanding and coming into contact with the chassis (C) by the compression member (330).

[0128] Meanwhile, although not shown in the drawing, the outer side of the fixing member (300') may further include an insulating member configured to at least partially surround the fixing member (300'). The insulating member may be configured to not only electrically insulate but also prevent heat conduction, etc.

[0129]

[0130] FIG. 13 is a schematic perspective view of a vehicle including a battery pack according to one embodiment of the present invention.

[0131] Referring to FIG. 13, a vehicle (3) according to one embodiment of the present invention may include one or more battery packs (1) according to one embodiment of the present invention. The vehicle (3) according to the present invention may be, for example, an electric vehicle, a hybrid vehicle, or a plug-in hybrid vehicle. The vehicle (3) includes a four-wheel vehicle and a two-wheel vehicle. The vehicle (3) operates by receiving power from a battery pack (1) according to one embodiment of the present invention.

[0132] A vehicle according to one embodiment of the present invention may include a battery pack (1) having a chassis (C); a plurality of battery cells (100), and a pack case (200) having an upper portion coupled to the chassis (C) and configured to accommodate the plurality of battery cells (100); and a fixing member (300) interposed between the pack case (200) and the chassis (C) and configured to suppress deformation of the pack case (200).

[0133] The edges of the chassis (C) and the pack case (200) may be fastened with bolts. In this case, if thermal runaway occurs in the battery cell (100), a strong restraining force may be applied to the edges of the pack case (200), causing thermal deformation of the upper surface of the pack case (200). In particular, the upper surface of the pack case (200) may be thermally deformed, causing a negative gap to occur, narrowing the gap of the venting space (S).

[0134] At this time, according to the above-described embodiment of the present invention, since the fixing member (300) is provided, the upper surface of the pack case (200) can be prevented from being thermally deformed and the occurrence of a minus gap. Therefore, according to the above-described aspect of the present invention, a path can be secured for high-temperature gases or flames generated in the battery cell (100) to be discharged to the outside of the battery pack (1) when the battery cell (100) is in an abnormal state. As a result, events due to thermal runaway of a device equipped with the battery pack (1), such as fire or explosion, can be prevented or delayed.

[0135] In addition, when thermal runaway occurs in the battery pack (1), a portion of the upper surface of the pack case (200) may swell upward due to pressure and / or heat, such as venting gas or flame. At this time, the fixing member (300) may be configured to allow the upper surface of the pack case (200) to swell to a certain degree. For example, since the fixing member (300) includes an elastic body such as a spring, the pack lid (220) may be compressed to the same height as the swell.

[0136] That is, the fixing member (300) can maintain the height of the venting space (S) above a certain distance by suppressing the minus gap of the pack lead (220) as much as possible and allowing a certain level of plus gap. Thus, according to the above-described embodiment of the present invention, when thermal runaway occurs inside the battery pack (1) and the pack lead (220) swells upward, the venting space (S) is further secured, so that the venting gas and the like can be discharged more smoothly to the outside of the pack case (200).

[0137]

[0138] Although the present invention has been described above with reference to limited embodiments and drawings, the present invention is not limited thereto, and it is obvious that various modifications and variations are possible within the scope of the technical idea of ​​the present invention and the equivalent scope of the claims to be described below by a person having ordinary skill in the art to which the present invention pertains.

Claims

1. In the battery pack mounted on the lower part of the chassis, Multiple battery cells; A pack case that accommodates the plurality of battery cells and has an upper portion configured to be coupled to the chassis; and A battery pack characterized by including a fixing member interposed between the pack case and the chassis and configured to suppress deformation of the pack case.

2. In paragraph 1, The above pack case is A case body having an open upper surface configured to accommodate the plurality of battery cells; A battery pack characterized by having a pack lid configured to cover the open upper surface of the case body.

3. In paragraph 1, A venting space is formed between the battery cell and the pack case, in which the venting gas generated from the battery cell is configured to flow. A battery pack characterized in that the above fixing member is configured to maintain the height of the venting space at a certain distance or more.

4. In paragraph 1, A battery pack characterized in that it further includes a module case configured to group the plurality of battery cells and having a venting hole formed on the upper surface thereof configured to discharge venting gas generated internally to the outside.

5. In paragraph 4, The above fixed member A battery pack characterized in that at least one is provided at a position corresponding to the central portion of the above module case.

6. In paragraph 1, The above fixed member A first connecting portion configured to penetrate the above-mentioned chassis from the outside; A battery pack characterized by including a second coupling portion configured to be coupled to the first coupling portion on the inside of the pack case.

7. In paragraph 6, The above fixed member A battery pack characterized by including a compression member provided between the pack case and the chassis and configured to at least partially surround the first coupling member.

8. In paragraph 7, The above fixing member is provided in multiple pieces, A battery pack, wherein at least some of the fixed members are configured such that the elastic moduli of the compression members are different from each other.

9. In paragraph 7, The above fixed member A battery pack characterized by including an insulating member configured to at least partially surround the compression member.

10. In paragraph 1, The above fixed member A battery pack characterized in that one end is configured to be fixed to the above-mentioned chassis, and the other end is configured to be fixed to the above-mentioned pack case and to be movable in the vertical direction.

11. In paragraph 1, A battery pack characterized in that the above-mentioned fixing member is provided as a spring whose one end and the other end are configured to be connected to the pack case and the chassis, respectively.

12. A vehicle comprising a battery pack according to any one of claims 1 to 11.

13. Shot; A battery pack comprising a plurality of battery cells and a pack case having an upper portion coupled to the chassis and configured to accommodate the plurality of battery cells; and An automobile characterized in that it includes a fixing member interposed between the pack case and the chassis and configured to suppress deformation of the pack case.

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