Battery pack and automobile including the battery pack

Abstract

One embodiment of the present invention relates to a battery pack including: a pack case having an internal space and a vent passageway that connects the internal space with an external space; and a battery module accommodated in the internal space of the pack case, the battery module including: a module case that accommodates the battery cells and has a vent hole formed therein that is configured to discharge vent gas generated in the battery cells to the outside; and an opening / closing member that is configured to open and close the vent hole so that the vent hole communicates with the vent passageway when opened.

Description

[Technical Field]

[0001] The present invention relates to a battery pack and a vehicle including the battery pack.

[0002] This application claims priority based on Korean Patent Application No. 10-2023-0159746, filed on November 17, 2023, the entire contents of which are incorporated herein by reference in their entirety in the specification and drawings thereof. [Background technology]

[0003] Secondary batteries, which have high applicability across product groups and electrical properties such as high energy density, are widely used not only in portable devices but also in electric vehicles (EVs), hybrid electric vehicles (HEVs), etc. These secondary batteries are attracting attention as a new energy source for improving energy efficiency, as they are environmentally friendly in that they do not produce any by-products from energy use, in addition to their primary advantage of dramatically reducing the use of fossil fuels.

[0004] Currently, secondary batteries such as lithium-ion batteries, lithium polymer batteries, nickel-cadmium batteries, nickel-metal hydride batteries, and nickel-zinc batteries are widely used. When a high output voltage is required, a battery module or a battery pack is formed by connecting multiple battery cells in series. To increase the charge / discharge capacity, a battery module or a battery pack may also be formed by connecting multiple battery cells in parallel. Therefore, the number of battery cells included in the battery module or pack may be variously set according to the required output voltage or charge / discharge capacity.

[0005] However, because battery cells undergo chemical reactions during charging and discharging, their performance may deteriorate if they are used in an environment that is higher than the appropriate temperature, and if heat cannot be controlled to the appropriate temperature, there is a risk of unexpected fire or explosion. Therefore, if a thermal event such as thermal runaway occurs inside a battery pack, high-temperature gases and flames emitted from the battery cells inside can spread to adjacent battery modules, causing a chain reaction of battery module explosions, which is extremely dangerous.

[0006] Therefore, it is necessary to develop a structure that can prevent or suppress the propagation of thermal runaway between battery modules by minimizing the thermal energy received by adjacent battery modules when thermal runaway occurs in a battery module.

[0007] In addition, it is necessary to develop a structure that can quickly exhaust high-temperature gases and flames generated in the battery module to the outside of the battery pack when thermal runaway occurs in the battery module, thereby eliminating heat accumulation inside the battery pack. Summary of the Invention [Problem to be solved by the invention]

[0008] Therefore, the problem to be solved by the present invention is to provide a battery pack that can prevent or suppress the propagation of thermal runaway between battery modules by minimizing the thermal energy received by adjacent battery modules when thermal runaway occurs in a battery module.

[0009] Another problem to be solved by the present invention is to provide a vehicle including such a battery pack.

[0010] However, the technical problem to be solved by the present invention is not limited to the above-mentioned object, and other objects and advantages not mentioned will be clearly understood by those skilled in the art from the following description. [Means for solving the problem]

[0011] In order to solve the above problems, one aspect of the present invention provides a battery pack including: a pack case having an internal space and a vent passage that connects the internal space with an external space; and a battery module housed in the internal space of the pack case, the battery module including: a module case that houses the multiple battery cells and has a vent hole that is configured to discharge vent gas generated in the battery cells to the outside; and an opening / closing member that is configured to open and close the vent hole so that the vent hole communicates with the vent passage when opened.

[0012] The opening and closing member may be configured to cover the vent hole and to open the vent hole with the vent gas.

[0013] The opening / closing member may be configured so that at least a portion thereof is movable toward the inside of the vent flow passage by the vent gas.

[0014] The pack case may include a cross beam configured to partition the interior space and having the vent passage formed therein.

[0015] The opening and closing member may be provided on a side surface of the module case facing the cross beam.

[0016] The opening and closing member may be configured to guide the vent gas in one direction through the vent passage when opened.

[0017] The pack case may be formed with a plurality of inlet holes that are provided to face the vent hole and are configured to allow the vent gas to flow into the vent flow path.

[0018] The opening / closing member may be configured to at least partially cover an inlet hole formed on another battery module side when moved.

[0019] The pack case may include a partition configured to divide the vent passage into a plurality of sections and having a partition hole formed therein, and the opening / closing member may be configured to cover the partition hole when moved.

[0020] The pack case may further include a cover member configured to cover the inlet hole so that the inlet hole is opened by the opening / closing member.

[0021] The cover member may be configured to be movable by the opening and closing member.

[0022] The cover member may be configured to be broken by the opening and closing member.

[0023] Another aspect of the present invention provides a vehicle including a battery pack according to an aspect of the present invention. [Effects of the Invention]

[0024] According to one aspect of the present invention, when thermal runaway occurs in a battery module, the thermal energy received by adjacent battery modules can be minimized, thereby preventing or suppressing the propagation of thermal runaway between battery modules and ensuring the safety and reliability of the battery pack.

[0025] Furthermore, according to one embodiment of the present invention, high-temperature gas, flames, and the like can be quickly discharged to the outside of the battery pack, thereby eliminating heat accumulation inside the battery pack.

[0026] Furthermore, according to one aspect of the present invention, events due to thermal runaway phenomena in a device to which a battery pack is attached, such as fires and explosions, can be prevented or delayed.

[0027] The present invention can also provide various other effects, which will be described in the respective embodiments, but the description of effects that can be easily inferred by those skilled in the art will be omitted.

[0028] The following drawings attached to this specification illustrate preferred embodiments of the present invention and, together with the detailed description of the invention, are intended to facilitate a further understanding of the technical concepts of the present invention; therefore, the present invention should not be interpreted as being limited to the matters described in the drawings. [Brief explanation of the drawings]

[0029] [Figure 1] 1 is an overall perspective view of a battery pack according to an embodiment of the present invention; [Figure 2] 1 is an exploded perspective view of a battery pack according to an embodiment of the present invention; [Figure 3] 1 is a partial cross-sectional view of a battery pack to which an opening / closing member according to an embodiment of the present invention is applied; [Figure 4] 4 is a diagram for explaining how the opening / closing member is opened when a thermal event occurs in the battery pack of FIG. 3. FIG. [Figure 5] 1 is a cross-sectional view of a battery pack according to one embodiment of the present invention, for example, a cross-sectional view taken along II' in FIG. [Figure 6] 10 is a partial cross-sectional view of a battery pack to which an opening / closing member according to another embodiment of the present invention is applied. [Figure 7] 7 is a diagram for explaining how the opening / closing member is opened when a thermal event occurs in the battery pack of FIG. 6. FIG. [Figure 8] 7 is a diagram illustrating another example in which the opening / closing member is opened when a thermal event occurs in the battery pack of FIG. 6. FIG. [Figure 9] 1 is a partial cross-sectional view of a battery pack according to an embodiment of the present invention. [Figure 10] 10 is a diagram for explaining how the opening / closing member is opened when a thermal event occurs in the battery pack of FIG. 9. FIG. [Figure 11] FIG. 10 is a partial cross-sectional view of a battery pack according to another embodiment of the present invention. [Figure 12] 12 is a diagram for explaining how the opening / closing member is opened when a thermal event occurs in the battery pack of FIG. 11. FIG. [Figure 13] 1 is a partial cross-sectional view of a battery pack to which a cover member according to an embodiment of the present invention is applied; [Figure 14] 14 is a diagram for explaining how the cover member is opened when a thermal event occurs in the battery pack of FIG. 13. FIG. [Figure 15] 14 is a diagram illustrating another example in which the cover member is opened when a thermal event occurs in the battery pack of FIG. 13. FIG. [Figure 16] 1 is a schematic perspective view of a vehicle including a battery pack according to an embodiment of the present invention. DETAILED DESCRIPTION OF THE INVENTION

[0030] Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings. Prior to this, the terms and phrases used in the specification and claims should not be construed as being limited to their general and dictionary meanings, but should be construed as having meanings and concepts corresponding to the technical ideas of the present invention, in accordance with the principle that the inventors themselves can appropriately define the concepts of terms in order to best describe the invention.

[0031] Therefore, it should be understood that the embodiments described in this specification and the configurations shown in the drawings are merely the most preferred embodiments of the present invention and do not represent the entire technical idea of ​​the present invention, and that there may be various equivalents and modifications that can replace them at the time of this application.

[0032] The present invention also includes various embodiments, and in each embodiment, overlapping descriptions of substantially identical or similar configurations will be omitted, and differences will be mainly described.

[0033] Meanwhile, although terms indicating directions such as up, down, left, right, front, and rear are used in this specification, it will be obvious to those skilled in the art that these terms are used for the convenience of explanation and may change depending on the position of the object of interest, the position of the observer, etc.

[0034] For example, in an embodiment of the present invention, the illustrated X-axis direction may refer to the front-to-back direction, the Y-axis direction may refer to the left-to-right direction perpendicular to the X-axis direction on a horizontal plane (XY plane), and the Z-axis direction may refer to the up-down direction (vertical direction) perpendicular to both the X-axis direction and the Y-axis direction.

[0035] Fig. 1 is an overall 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, Fig. 3 is a partial cross-sectional view of a battery pack to which an opening / closing member according to an embodiment of the present invention is applied, and Fig. 4 is a view illustrating how the opening / closing member is opened when a thermal event occurs in the battery pack of Fig. 3.

[0036] 1 to 4, a battery pack 10 according to an embodiment of the present invention includes a pack case 100 and a battery module 200.

[0037] The pack case 100 may be configured to form an internal space S. In order to safely protect the battery modules 200 housed therein, the pack case 100 may be made of or include a material capable of ensuring mechanical rigidity, such as a metal such as steel or SUS (Steel Use Stainless), or a plastic.

[0038] The pack case 100 may also include a vent flow path P. The vent flow path P may refer to a passage through which vent gas or the like flows. The vent flow path P may be configured to communicate between the internal space S and the external space of the pack case 100.

[0039] The vent passage P may be formed inside the pack case 100. Here, the inside of the pack case 100 may be a predetermined space separately provided inside the pack case 100, or may be a hollow formed in a plurality of beams or plates constituting the pack case 100, as shown in FIG.

[0040] The battery module 200 may be configured to be accommodated in an internal space S of the pack case 100. The pack case 100 may be formed with a plurality of accommodation spaces configured to accommodate a plurality of battery modules 200 in a divided manner.

[0041] The plurality of battery modules 200 may be arranged adjacent to each other in a plurality of rows along the front-rear direction and / or the left-right direction. For example, as shown in Fig. 2, the plurality of battery modules 200 may be arranged in four rows along the front-rear direction (X-axis direction) and two rows along the left-right direction (Y-axis direction).

[0042] The battery module 200 may include a plurality of battery cells 210, a module case 220, and an opening / closing member 230.

[0043] 2, the battery may include a plurality of battery cells 210. Although not shown, the plurality of battery cells 210 may include an electrode assembly, a cell case that houses the electrode assembly, and electrode leads that are connected to the electrode assembly and extend to the outside of the cell case to function as electrode terminals. In this case, the plurality of battery cells 210 may be electrically connected to each other.

[0044] The battery cell 210 may be a pouch-type secondary battery. The cell case of such a pouch-type secondary battery may be configured in a pouch shape with a metal layer including an aluminum material sandwiched between polymer layers.

[0045] As shown in FIG. 2, the plurality of battery cells 210 may be arranged side by side in the front-to-rear direction (X-axis direction) while standing upright in the vertical direction (Z-axis direction).

[0046] Meanwhile, the present invention is not limited to a specific type or shape of the battery cell 210, and various battery cells 210 known at the time of filing of the present invention may be adopted in the configuration of the battery pack 10 of the present invention. In the present embodiment, as shown in the drawing, a pouch-type secondary battery that has high energy density and is easy to stack is targeted, but it goes without saying that a cylindrical secondary battery or a prismatic secondary battery may also be applied as the battery cell 210.

[0047] The module case 220 may be configured to have an empty space formed therein and to accommodate at least some of the plurality of battery cells 210. In other words, the module case 220 may group the plurality of battery cells 210 into several battery modules 200 and serve as a boundary that physically defines the interior space of each battery module 200.

[0048] Although not shown, the battery module 200 may also include a bus bar assembly and / or module terminals electrically connected to the plurality of battery cells 210 housed therein.

[0049] A vent hole 220a may be formed in the module case 220. The vent hole 220a may be configured to allow vent gas generated in the battery cells 210 housed inside the module case 220 to be discharged to the outside of the module case 220.

[0050] Specifically, the vent hole 220a may be provided in the module case 220 to enable directional venting in a specific direction. In particular, the vent hole 220a may be provided on one surface of the module case 220 that faces the vent flow path P.

[0051] According to this embodiment, vent gases and the like discharged from the vent hole 220a can move straight to the vent flow path P formed in the pack case 100, so that the vent gases and the like can be discharged to the outside of the pack case 100 more quickly.

[0052] Meanwhile, the opening / closing member 230 may be configured to open and close the vent hole 220a. The opening / closing member 230 may be provided on one surface of the module case 220 where the vent hole 220a is formed. As shown in FIG. 3, the opening / closing member 230 may be configured to cover the vent hole 220a.

[0053] 4, the opening / closing member 230 may be configured to open the vent hole 220a when a thermal event occurs. Specifically, the opening / closing member 230 may be configured to open the vent hole 220a with vent gas generated when a thermal event occurs in the battery cell 210. The vent hole 220a may be configured to communicate with the vent flow path P when the opening / closing member 230 is opened. As a result, when the opening / closing member 230 is opened, the vent gas discharged through the vent hole 220a flows into the vent flow path P formed inside the pack case 100.

[0054] According to the present embodiment, when thermal runaway occurs in a battery cell 210, high-temperature gases and flames generated in each battery module 200 can be individually discharged to the outside, thereby minimizing heat propagation to battery cells 210 installed in other battery modules 200. That is, according to the present embodiment, even if a thermal event occurs in any battery module 200, it can be prevented from affecting the other battery modules 200. As a result, propagation of thermal runaway within the battery pack 10 can be prevented or suppressed, and the safety and reliability of the battery pack 10 can be ensured.

[0055] Furthermore, according to the present embodiment, vent gas generated in the battery cell 210 flows into the vent passage P through the vent hole 220a and can be quickly discharged to the outside of the pack case 100. This can eliminate heat accumulation inside the battery pack 10.

[0056] 4, the opening / closing member 230 may be configured so that at least a portion thereof is movable by the vent gas. The opening / closing member 230 may be configured so that the entire opening / closing member 230 moves, or so that only a portion of the opening / closing member 230 moves.

[0057] The opening / closing member 230 may move toward the inside of the vent flow path P. Specifically, the opening / closing member 230 may move toward the inside of the vent flow path P due to the pressure of the vent gas discharged from the vent hole 220a provided in the battery module 200 in which a thermal event has occurred.

[0058] As an example, the opening / closing member 230 may include a plate-shaped cover plate 231 and an elastic portion 232 connected to the cover plate 231. The cover plate 231 may be made of a material having heat resistance and / or fire resistance. The cover plate 231 may cover the vent hole 220a and may be configured to be movable in one direction by the vent gas.

[0059] At this time, the elastic portion 232 may be configured to control the movement of the cover plate 231. That is, the cover plate 231 may move in one direction due to the elastic force of the elastic portion 232 and the pressure of the vent gas. Furthermore, the open / close member 230 may be configured to return to its original position due to the elastic force of the elastic portion 232 and cover the vent hole 220a when the discharge of the vent gas stops.

[0060] As another example, although not shown, at least a portion of the opening / closing member 230 may be configured to be elastically deformed by the vent gas. In this case, both side ends of the opening / closing member 230 may be configured to be fixed to the module case 220. In addition, the cover plate 231 of the opening / closing member 230 may be made of an elastic pad or the like. According to this embodiment, when the vent gas flows into the vent flow path P through the vent hole 220a, the pressure of the vent gas causes the center of the cover plate 231 to elastically deform, and the cover plate 231 can move to open the vent hole 220a.

[0061] 5 is a cross-sectional view of a battery pack according to one embodiment of the present invention, for example, taken along II' in FIG.

[0062] Meanwhile, referring mainly to FIGS. 2 and 5, the pack case 100 may include a base frame 110 and a plurality of side frames 120.

[0063] The base frame 110 may be configured to mount a plurality of battery cells 210. The base frame 110 forms the bottom surface of the pack case 100 and may be a rectangular plate. The base frame 110 may have a flat top surface on which the module case 220 may be stably mounted.

[0064] The multiple side frames 120 may extend upward from each side of the base frame 110. The multiple side frames 120 may be provided to surround the multiple battery cells 210. More specifically, each of the multiple side frames 120 may form a side surface of the pack case 100, including a right wall located at the end of the base frame 110 in the -Y axis direction, a rear wall located at the end in the +X axis direction, a left wall located at the end in the +Y axis direction, and a front wall located at the end in the -X axis direction.

[0065] The pack case 100 may also include a center beam 140. The center beam 140 may be provided to connect opposing side frames 120 of the multiple side frames 120 to each other. For example, as shown in FIG. 5 , at least one of the center beams 140 may extend in the left-right direction and be provided to connect the right side wall and the left side wall of each side frame 120.

[0066] Furthermore, the center beam 140 may be configured to separate the battery modules 200 arranged in multiple rows. For example, the center beam 140 may be provided between the battery modules 200 arranged in two rows in the left-right direction. This allows the battery modules 200 to be spaced apart by the center beam 140.

[0067] The pack case 100 may also include a cross beam 130. The cross beam 130 may be configured to partition the interior space of the pack case 100. For example, the cross beam 130 may be configured to partition a plurality of battery modules 200.

[0068] A plurality of cross beams 130 may be provided. The cross beams 130 may be provided to connect the side frames 120 and the center beam 140. For example, as shown in Fig. 5, the cross beams 130 may be provided to connect the left and right side walls of the side frames 120 to the center beam 140, respectively. As a result, the cross beams 130 may be provided between each of the plurality of battery modules 200 arranged in four rows along the front-rear direction, thereby dividing the battery modules 200.

[0069] In this case, the cross beam 130 may be provided to protrude above the battery cells 210. According to the present embodiment, the cross beam 130 extends above the battery cells 210, thereby reliably separating adjacent battery modules 200 by the cross beam 130 and preventing heat propagation.

[0070] The vent channel P may be formed inside the cross beam 130. The vent channel P of the cross beam 130 may be provided to communicate with at least one battery module 200. In this case, the vent hole 220a may be formed on a side surface of the module case 220 facing the cross beam 130. The opening / closing member 230 may also be provided on a side surface of the module case 220 facing the cross beam 130.

[0071] As a result, when the opening / closing member 230 is opened, vent gas generated in the battery cell 210 can pass through the vent hole 220a and move directly to the vent passage P formed inside the cross beam 130.

[0072] 2, the pack case 100 may include an exhaust unit 150. The exhaust unit 150 may be configured to exhaust gas generated in the battery cells 210 to the outside of the pack case 100. For example, the vent gas in the vent flow path P may be configured to be exhausted to the outside of the pack case 100 through the exhaust unit 150.

[0073] When vent gas is generated inside the pack case 100 and the internal pressure increases, the exhaust part 150 may be configured to be opened by the pressure of the vent gas and exhaust the vent gas to the outside of the pack case 100 .

[0074] For example, the vent 150 may be configured to open and close depending on the internal pressure of the pack case 100. Alternatively, the vent 150 may be configured in the form of a hole. Meanwhile, the present invention is not limited to the specific type or form of the vent 150, and various vents 150 known at the time of filing of the present invention may be adopted in the configuration of the battery pack 10 of the present invention.

[0075] Specifically, the discharge portion 150 may be provided on a side surface of the pack case 100, i.e., on the side frame 120. A plurality of discharge portions 150 may be provided. The discharge portion 150 may be provided on at least one of the plurality of side frames 120. The discharge portion 150 may be formed on each of two or more side frames 120, or two or more discharge portions 150 may be formed on one side frame 120.

[0076] Meanwhile, the number and positions of the discharge units 150 described based on the embodiment of FIG. 2 are merely examples, and it goes without saying that they can be changed to various numbers and positions.

[0077] 5, vent channels P may be formed inside the plurality of side frames 120. As a result, as indicated by the arrows in FIG. 5, vent gas generated inside the battery module 200 may move through the vent holes 220a to the vent channels P formed in the cross beam 130, and then move to the vent channels P formed in the side frames 120. The vent gas may be discharged to the outside of the pack case 100 through the discharge ports 150 provided in the side frames 120.

[0078] According to this embodiment, the vent gas etc. moves directly to the vent flow path P of the side frame 120 where the discharge portion 150 is provided, so that the vent gas etc. can be quickly discharged to the outside of the pack case 100.

[0079] Meanwhile, the battery pack 10 according to an embodiment of the present invention may further include a pack lid 300. The pack lid 300 may be coupled to the upper part of the side frame 120 to form the top surface of the pack case 100.

[0080] Fig. 6 is a partial cross-sectional view of a battery pack to which an opening / closing member according to another embodiment of the present invention is applied. Fig. 7 is a view illustrating how the opening / closing member is opened when a thermal event occurs in the battery pack of Fig. 6. Fig. 8 is a view illustrating another example of how the opening / closing member is opened when a thermal event occurs in the battery pack of Fig. 6.

[0081] 6 to 8, the opening / closing member 230 may include a cover plate 231 and a hinge portion 233.

[0082] The cover plate 231 may be configured to cover the vent hole 220a. The cover plate 231 may be provided on the module case 220. The cover plate 231 may be configured to open or close the vent hole 220a depending on the pressure of the vent gas due to thermal runaway of the battery cell 210.

[0083] The cover plate 231 may be pivotally coupled to the vent hole 220a via a hinge portion 233. The hinge portion 233 may be coupled to the cover plate 231. The hinge portion 233 may be configured to include an elastic body to control the rotational movement of the cover plate 231. For example, the elastic body may be a hinge spring.

[0084] Specifically, when thermal runaway does not occur in the battery cell 210, the cover plate 231 can maintain the vent hole 220a in a closed state by the elastic force of the elastic body provided in the hinge portion 233.

[0085] Meanwhile, when the internal pressure of the battery module 200 rises above a reference pressure due to thermal runaway of the battery cells 210, the cover plate 231 may be configured to open to the vent passage P side to exhaust vent gas and / or flames to the outside of the battery module 200. When the internal pressure of the battery module 200 is above the reference pressure, this may mean that the internal pressure of the battery module 200 is higher than the pressure of the vent passage P due to the generation of vent gas. In this case, the pressurizing force of the air inside the battery module 200 applied to the cover plate 231 by the vent gas may be greater than the elastic force of the hinge part 233 that tries to maintain the cover plate 231 in a closed state.

[0086] According to this embodiment, when a thermal event occurs in a battery module 200, the pressure of the vent gas causes the cover plate 231 to open, allowing the vent gas to be quickly discharged to the outside of the battery module 200 through the vent hole 220a.

[0087] When the opening / closing member 230 is opened by the pressure of the vent gas, the cover plate 231 may be opened at an acute angle to the vent hole 220a. According to the present embodiment, the vent gas, etc. discharged from the inside of the battery module 200 due to thermal runaway of the battery cell 210 is discharged to the vent passage P along the inner surface of the cover plate 231 disposed obliquely with respect to the vent hole 220a. This makes it possible to more reliably guide the flow of the vent gas, etc. toward the vent passage P.

[0088] Furthermore, the cover plate 231 may be configured to open only in one direction. In this case, the one direction may be defined as a direction toward the inside of the vent channel P. More specifically, all of the cover plates 231 provided in the vent holes 220a may be configured to open only in a direction toward the inside of the vent channel P. As a result, the opening direction of the cover plate 231 provided in the vent hole 220a of the battery module 200 in which a thermal event has occurred may be opposite to the opening direction of the cover plate 231 provided in the vent hole 220a of the adjacent battery module 200.

[0089] According to the present embodiment, the vent hole 220a provided in the battery module 200 in which a thermal event has occurred and the vent holes 220a provided in the other battery modules 200 are prevented from being opened simultaneously. This prevents vent gas, heat, and the like from being transferred to the battery cells 210 provided in the other battery modules 200, thereby enhancing the safety of the battery pack 10.

[0090] Furthermore, the cover plate 231 may be configured to close the battery module 200 when the internal pressure of the battery module 200 drops below a reference pressure due to the vent gas being discharged to the outside. When the internal pressure of the battery module 200 drops below the reference pressure, this may mean that the vent gas is discharged to the outside and the internal pressure of the battery module 200 is lower than the pressure of the vent channel P. In this case, not only the pressure of the vent channel P applied to the cover plate 231 but also the elastic force of the hinge unit 233 that tries to maintain the closed state of the cover plate 231 may be applied. Therefore, when the internal pressure of the battery module 200 drops due to the vent gas being discharged to the outside, the cover plate 231 may be smoothly driven toward the outside of the vent channel P due to the pressure difference between the inside of the battery module 200 and the vent channel P, thereby closing the battery module 200.

[0091] According to this embodiment, when the amount of vent gas discharged decreases, the cover plate 231 can easily close the battery module 200, thereby reliably blocking backflow of vent gas and / or flame into the battery module 200. In addition, blocking the inflow of oxygen into the battery module 200 can suppress additional ignition within the battery module 200.

[0092] 7 and 8, the opening / closing member 230 may be configured to guide the vent gas in one direction toward the vent passage P when opened. That is, the opening / closing member 230 may be configured to open in a direction when opened. Here, the one direction may be defined as a direction toward the side frame 120.

[0093] According to the present embodiment, when the vent passage P is also formed in the side frame 120, the vent gas can quickly move to the vent passage P formed in the side frame 120 and be discharged to the outside through the discharge part 150. This can eliminate heat accumulation inside the battery pack 10.

[0094] Specifically, the opening / closing member 230 may include a plurality of cover plates 231. As an example, referring to FIG. 7, the plurality of cover plates 231 may be configured with different lengths. A relatively long cover plate 231 may block the vent gas from passing over the relatively long cover plate 231. In such a case, the vent gas may be guided to move along the inner surface of the long cover plate 231. Thus, by varying the lengths of the cover plates 231, the flow of vent gas, etc., toward the side frame 120 within the vent flow path P can be more reliably guided.

[0095] As another example, referring to FIG. 8 , the cover plate 231 may be made of an elastic material having elasticity. In this case, the plurality of cover plates 231 may be configured to have different elasticities. That is, the plurality of cover plates 231 may be configured to bend to different degrees due to the vent gas. In this case, the plurality of cover plates 231 may be configured to have different opening angles. A cover plate 231 having a relatively low elasticity may be opened at a relatively smaller angle than the other cover plates 231. This may induce the vent gas to move along the inner surface of the cover plate 231 having a relatively low elasticity. This may allow the flow of vent gas, etc., toward the side frame 120 within the vent passage P to be more reliably guided by adjusting the elasticity of the cover plate 231.

[0096] FIG. 9 is a partial cross-sectional view of a battery pack according to an embodiment of the present invention, and FIG. 10 is a view illustrating how the opening and closing member is opened when a thermal event occurs in the battery pack of FIG.

[0097] 9, an inlet hole H may be formed in the pack case 100. The inlet hole H may be configured so that the vent gas discharged from the vent hole 220a flows into the vent flow path P. That is, the inlet hole H may be configured so as to communicate between the vent hole 220a and the vent flow path P. In this case, the inlet hole H may be provided so as to face the vent hole 220a. A plurality of inlet holes H may be provided.

[0098] As an example, a plurality of inlet holes H may be provided in one cross beam 130. The plurality of inlet holes H may be provided alternately. In other words, the plurality of inlet holes H may be provided so as not to face each other. This makes it possible to prevent vent gas discharged from one battery module 200 to an inlet hole H from flowing again into another battery module 200 through another inlet hole H.

[0099] As another example, the inlet holes H may be provided to face each other in the pack case 100. That is, an inlet hole H formed on the side of one battery module 200 may be configured to face and directly communicate with an inlet hole H formed on the side of another battery module 200.

[0100] In this case, if a thermal event occurs in a battery module 200, vent gas may flow into the adjacent battery module 200 through the inlet H. To prevent this, as in the embodiment shown in Fig. 10, the open / close member 230 may be configured to at least partially cover the inlet H formed on the adjacent battery module 200 when moved by the vent gas. That is, when the open / close member 230 is opened, the open / close member 230 may be configured to pass through the inlet H and close the adjacent inlet H.

[0101] According to this embodiment, the opening and closing member 230 closes the other inlet holes H, thereby preventing the vent gas from flowing into the adjacent battery module 200 through the other inlet holes H. Therefore, the propagation of thermal runaway between the battery modules 200 can be more reliably suppressed or blocked.

[0102] FIG. 11 is a partial cross-sectional view of a battery pack according to another embodiment of the present invention, and FIG. 12 is a view illustrating how the opening and closing member is opened when a thermal event occurs in the battery pack of FIG.

[0103] According to another embodiment of the present invention, as shown in Fig. 11, the pack case 100 may include a partition wall 160. The partition wall 160 may be configured to divide the vent flow path P inside the pack case 100 into a plurality of sections. The partition wall 160 may be configured to horizontally separate the vent flow path P. A partition wall hole 160a may be formed in the partition wall 160. In this case, the partition wall hole 160a may be configured to face the inlet hole H and / or the vent hole 220a.

[0104] 12, the opening / closing member 230 may be configured to cover the partition hole 160a when moved by the vent gas. That is, when the opening / closing member 230 is opened, the opening / closing member 230 may be configured to pass through the inlet hole H and close the partition hole 160a.

[0105] According to this embodiment, the opening / closing member 230 closes the partition hole 160a, thereby preventing vent gas from flowing through the partition hole 160a into the adjacent battery module 200. Therefore, the propagation of thermal runaway between the battery modules 200 can be more reliably suppressed or blocked.

[0106] Furthermore, the partition 160 may be configured to function as a stopper when the open / close member 230 is opened. Therefore, the partition hole 160a may be smaller than the inlet hole H. According to this embodiment, it is possible to prevent the open / close member 230 from moving beyond the partition 160. Furthermore, if the open / close member 230 includes an elastic portion 232, the elastic portion 232 is restricted from being infinitely stretched. As a result, the open / close member 230 may be configured to return to its original position and cover the vent hole 220a when the discharge of vent gas stops.

[0107] Although not shown, the partition wall 160 may be configured to be inclined inside the vent flow path P. In this case, when the open / close members 230 are all open, the partition wall 160 may be configured to have a directional property. According to this embodiment, the open / close members 230 and the partition wall 160 allow the vent gas to move in a desired direction and be quickly discharged to the outside of the pack case 100.

[0108] Fig. 13 is a partial cross-sectional view of a battery pack to which a cover member according to an embodiment of the present invention is applied. Fig. 14 is a view illustrating how the cover member is opened when a thermal event occurs in the battery pack of Fig. 13. Fig. 15 is a view illustrating another example of how the cover member is opened when a thermal event occurs in the battery pack of Fig. 13.

[0109] In yet another embodiment, the pack case 100 may further include a cover member 170. The cover member 170 may be configured to cover the inlet hole H. The cover member 170 may be configured to open and close the inlet hole H. Specifically, the cover member 170 may be configured to open the inlet hole H by the opening and closing member 230 when a thermal event occurs. That is, the cover member 170 may be configured to be opened by the opening and closing member 230 together with the opening of the opening and closing member 230. In this way, the vent hole 220a, the inlet hole H, and the vent flow path P may all be configured to communicate with each other.

[0110] As a result, only the inlet hole H provided on the battery module 200 side where the thermal event occurred is opened, and the inlet holes H provided on the other adjacent battery modules 200 side may be kept closed by the cover member 170. According to the present embodiment, since the cover member 170 closes the inlet hole H, it is possible to prevent vent gas from flowing into the other adjacent battery module 200 side through the inlet hole H. Therefore, it is possible to more reliably suppress or block the propagation of thermal runaway between the battery modules 200.

[0111] 14 , the cover member 170 may be configured to be at least partially movable by the opening / closing member 230. The cover member 170 may be configured to move together with the opening / closing member 230 when the opening / closing member 230 is opened. In particular, the opening / closing member 230 may be configured to push out the cover member 170. That is, the opening / closing member 230 may be configured to press against the cover member 170. The cover member 170 may be configured to move as a whole, or only a portion of the opening / closing member 230 may be moved.

[0112] The cover member 170 may move toward the inside of the vent flow path P. Specifically, the cover member 170 may move toward the inside of the vent flow path P due to the pressure of the vent gas discharged from the vent hole 220a of the battery module 200 in which a thermal event has occurred.

[0113] 15, the cover member 170 may be configured to be broken by the open / close member 230. That is, the cover member 170 may be configured to be ruptured by the open / close member 230. In particular, the cover member 170 may be configured such that when the open / close member 230 is opened, an end of the open / close member 230 breaks the cover member 170. This allows the vent gas to flow into the vent flow path P through a gap created when the cover member 170 is broken.

[0114] In this case, the cover member 170 may be made of a thin film that is easily ruptured. Also, a notch may be formed in the cover member 170. This allows the cover member 170 to be configured so that it can be easily ruptured by the opening and closing member 230 being opened by the vent gas when a thermal event occurs.

[0115] FIG. 16 is a schematic perspective view of a vehicle including a battery pack according to one embodiment of the present invention.

[0116] 16, an automobile 20 according to an embodiment of the present invention may include one or more battery packs 10 according to an embodiment of the present invention. The automobile 20 according to the present invention may be, for example, an electric vehicle, a hybrid vehicle, or a plug-in hybrid vehicle. The automobile 20 includes four-wheeled vehicles and two-wheeled vehicles. The automobile 20 may operate by receiving power from the battery pack 10 according to an embodiment of the present invention.

[0117] As described above, the present invention has been described using limited embodiments and drawings, but the present invention is not limited thereto, and it goes without saying that various changes and modifications can be made by a person having ordinary knowledge in the technical field to which the present invention pertains within the technical spirit of the present invention and the equivalent scope of the claims.

Claims

1. a pack case having an internal space and a vent passage that connects the internal space with an external space; a battery module accommodated in an internal space of the pack case, the battery module including: a plurality of battery cells; a module case accommodating the plurality of battery cells and having a vent hole formed therein configured to discharge vent gas generated in the battery cells to the outside; and an opening / closing member configured to open and close the vent hole, and configured to allow the vent hole to communicate with the vent flow path when opened; The pack case includes: a plurality of inlet holes formed in the battery pack, the inlet holes being arranged to face the vent hole and configured to allow the vent gas to flow into the vent flow path when the opening / closing member is opened;

2. The battery pack according to claim 1 , wherein the opening / closing member is configured to cover the vent hole and to open the vent hole with the vent gas.

3. The battery pack according to claim 1 , wherein at least a portion of the opening / closing member is configured to be movable toward the inside of the vent flow path by the vent gas.

4. The battery pack according to claim 1 , wherein the pack case includes a cross beam configured to partition the internal space and having the vent passage formed therein.

5. The battery pack according to claim 4 , wherein the opening and closing member is provided on a side surface of the module case facing the cross beam.

6. The battery pack according to claim 1 , wherein the opening / closing member is configured to guide the vent gas in one direction through the vent passage when opened.

7. A pack case having an internal space and a vent flow path that connects the internal space with an external space; a battery module accommodated in an internal space of the pack case, the battery module including: a plurality of battery cells; a module case accommodating the plurality of battery cells and having a vent hole formed therein configured to discharge vent gas generated in the battery cells to the outside; and an opening / closing member configured to open and close the vent hole, and configured to allow the vent hole to communicate with the vent flow path when opened; the opening / closing member is configured so that at least a portion thereof can be moved toward the inside of the vent flow path by the vent gas, the pack case is provided with a plurality of inlet holes that are arranged to face the vent hole and that are configured to allow the vent gas to flow into the vent flow path, The opening / closing member is configured to at least partially cover an inlet hole formed on another battery module side when moved.

8. A pack case having an internal space and a vent flow path that connects the internal space with an external space; a battery module accommodated in an internal space of the pack case, the battery module including: a plurality of battery cells; a module case accommodating the plurality of battery cells and having a vent hole formed therein configured to discharge vent gas generated in the battery cells to the outside; and an opening / closing member configured to open and close the vent hole, and configured to allow the vent hole to communicate with the vent flow path when opened; the opening / closing member is configured so that at least a portion thereof can be moved toward the inside of the vent flow path by the vent gas, the pack case includes a partition wall configured to divide the vent flow path into a plurality of sections and having partition holes formed therein; The opening / closing member is configured to cover the partition hole when moved.

9. A pack case having an internal space and a vent flow path that connects the internal space with an external space; a battery module accommodated in an internal space of the pack case, the battery module including: a plurality of battery cells; a module case accommodating the plurality of battery cells and having a vent hole formed therein configured to discharge vent gas generated in the battery cells to the outside; and an opening / closing member configured to open and close the vent hole, and configured to allow the vent hole to communicate with the vent flow path when opened; the opening / closing member is configured so that at least a portion thereof can be moved toward the inside of the vent flow path by the vent gas, the pack case is provided with a plurality of inlet holes that are arranged to face the vent hole and that are configured to allow the vent gas to flow into the vent flow path, The pack case further includes a cover member configured to cover the inlet hole and configured to open the inlet hole by the opening / closing member.

10. The battery pack according to claim 9 , wherein the cover member is configured to be movable by the opening / closing member.

11. The battery pack according to claim 9 , wherein the cover member is configured to be broken by the opening / closing member.

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

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