Battery pack and automobile including same

Abstract

The present invention discloses a battery pack with improved internal pressure resistance. The battery pack according to one aspect of the present invention includes at least one battery module and a pack case that houses the battery module in an internal space, the pack case including a case body that is provided with an internal space and that has an opening on at least one of one side and the other side opposite the one side, and an enclosure that is coupled to the case body to seal the opening so as to prevent the opening from being exposed to the outside of the pack case.

Description

[Technical Field]

[0001] The present invention relates to a battery pack and a vehicle including the same, and more particularly to a battery pack having improved internal pressure resistance and a vehicle including the same. This application claims priority based on Korean Patent Application No. 10-2022-0183750 filed on December 23, 2022 and Korean Patent Application No. 10-2023-0083037 filed on June 27, 2023, and the contents disclosed in the specifications and drawings of said applications are incorporated herein in their entirety. [Background technology]

[0002] In recent years, secondary batteries have been widely used for driving and storing energy not only in small devices such as portable electronic devices but also in medium- to large-sized devices such as electric vehicles and energy storage systems (ESS). A battery module is formed by housing a plurality of such secondary batteries together in a module case while electrically connected, and further, a battery pack is formed by electrically connecting such battery modules in a small space to increase energy density.

[0003] However, when multiple battery modules are packed together in a small space, they can be vulnerable to fires, explosions, and other accidents. For example, if a thermal runaway occurs in one battery module, high-temperature vent gas may be released from the battery module. If the high-temperature vent gas is not properly released, a sudden increase in internal pressure can cause the battery pack to explode, or gas or flames can be released in an unintended direction, resulting in personal injury.

[0004] To solve this problem, vent devices are used to exhaust gases and flames in the intended direction, minimizing damage caused by gases and flames. However, if a leak occurs due to deformation of the battery housing before the internal pressure of the vent device reaches the allowable limit, the vent location can occur randomly, posing a safety hazard. Summary of the Invention [Problem to be solved by the invention]

[0005] The present invention has been made in consideration of the above-mentioned problems, and aims to provide a battery pack configured to increase resistance to internal pressure of the battery pack, and a vehicle including the battery pack.

[0006] Another object of the present invention is to provide a battery pack configured to ensure airtightness, watertightness, and ease of assembly due to assembly position constraints, and a vehicle including the battery pack.

[0007] It is yet another object of the present invention to provide a battery pack and a vehicle including the same that are configured so that the structure can be adjusted to match the timing at which venting due to internal pressure should occur.

[0008] However, the technical problems that the present invention aims to solve are not limited to the problems described above, and other problems not mentioned will be clearly understood by those skilled in the art from the description of the invention described below. [Means for solving the problem]

[0009] In order to achieve the above object, a battery pack according to one aspect of the present invention includes at least one battery module and a pack case that houses the battery module in an internal space, and the pack case may include: a case body that is provided with the internal space and that is configured to have an opening on at least one of one side and the other side opposite the one side; and an enclosure that is configured to be coupled to the case body to seal the opening so as to prevent the opening from being exposed to the outside of the pack case.

[0010] The enclosure may have a protrusion on its outer surface that joins with the case body, protruding toward the inner surface of the case body, and the case body may have a recess on its inner surface that is formed to correspond to the protrusion.

[0011] The enclosure may include a cover portion that covers the opening, and the protrusion may be formed on at least one of both ends of the cover portion and protrude toward the inner surface of the case body.

[0012] The protrusions may be formed at both ends of the cover portion and extend from both ends of the cover portion so as to protrude a predetermined length toward the inner surface of the case body.

[0013] The protrusion may be tapered from at least one end of the cover toward the inner surface of the case body.

[0014] The protrusion may have a V-shaped cross section.

[0015] The enclosure may have a plate shape and be connected to the case body on one side and the other side, and the protrusions may be provided at one corner and the other corner of the enclosure, respectively.

[0016] The protrusions may be composed of two pairs, one pair provided at one corner and one pair provided at the other corner of the enclosure, and the pair of protrusions provided at the one corner and the other corner may be arranged at a predetermined distance from each other in the width direction of the enclosure.

[0017] The battery pack may include a seal member interposed between the enclosure and the case body.

[0018] The sealing member may be disposed between a pair of protrusions provided at the one corner and the other corner, respectively.

[0019] The battery pack may include a vent device provided in the enclosure and configured to exhaust gas generated from the battery module to the outside of the pack case.

[0020] Additionally, a vehicle according to the present invention may include a battery pack according to the above-described embodiment. [Effects of the Invention]

[0021] According to one aspect of the present invention, by sealing the open portion, the airtight performance of the pack case is ensured, and unintended leakage of gas or flames to the outside of the pack case can be effectively prevented in the event of a thermal event in the battery module.

[0022] According to another aspect of the present invention, it is possible to improve the resistance to internal pressure of a battery pack. Even if the internal pressure in the battery pack increases, the battery pack can have strong resistance to shear stress caused by the internal pressure. This also improves the airtightness and watertightness of the battery pack.

[0023] According to yet another aspect of the present invention, the height and / or thickness of the protrusions and recesses can be adjusted depending on the level of internal pressure that can be resisted, thereby enabling the structure of the battery pack to be designed in accordance with the timing at which venting should occur in response to the internal pressure.

[0024] According to another aspect of the present invention, the bonding area between the case body and the enclosure can be further increased to enhance bonding strength. Furthermore, when the internal pressure of the battery pack increases and venting occurs, the number of gas transfer paths between the case body and the enclosure increases. Even if the connection between the case body and the enclosure in a portion adjacent to the interior of the battery pack is temporarily released, the gas can be vented to another path via a vent hole (described below), allowing the case body and the enclosure to be reconnected. In other words, the resistance of the battery pack to internal pressure can be further enhanced.

[0025] According to yet another aspect of the present invention, the case body and the enclosure can be easily joined together.

[0026] According to yet another aspect of the present invention, the sealing member can increase the bonding strength between the case body and the enclosure. In particular, if a gap (play) occurs between the case body and the enclosure due to manufacturing errors, the gap can reduce the watertight and airtight performance of the battery pack, but the sealing member can prevent this. [Brief explanation of the drawings]

[0027] [Figure 1] 1 is a diagram showing the appearance of a battery pack according to an embodiment of the present invention; [Figure 2] 1 is a diagram showing components of a battery pack according to an embodiment of the present invention separated from one another; [Figure 3] 4A and 4B are diagrams illustrating a coupling relationship between a case body and an enclosure included in a battery pack according to an embodiment of the present invention. [Figure 4]FIG. 4 is an enlarged view of a part of FIG. 3. [Figure 5] FIG. 2 illustrates an enclosure included in a battery pack according to an embodiment of the present invention. [Figure 6] FIG. 2 is a diagram illustrating some components included in a battery pack according to an embodiment of the present invention. [Figure 7] FIG. 2 is a diagram illustrating some components included in a battery pack according to an embodiment of the present invention. [Figure 8] FIG. 2 is a diagram illustrating some components of a battery pack according to another embodiment of the present invention. [Figure 9] FIG. 9 is a cross-sectional view of a portion of the configuration included in the battery pack of FIG. 8. [Figure 10] 10A and 10B are diagrams illustrating a coupling relationship between a case body and an enclosure included in a battery pack according to still another embodiment of the present invention. [Figure 11] 1 illustrates a vehicle according to an embodiment of the present invention; DETAILED DESCRIPTION OF THE INVENTION

[0028] Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings. The drawings attached to this specification are intended to illustrate preferred embodiments of the present invention and, together with the detailed description of the invention to be given later, serve to further understand the technical concepts of the present invention. Therefore, the present invention should not be interpreted as being limited to the details shown in such drawings. The same reference numerals refer to the same components. Furthermore, in the drawings, the thickness, ratio, and dimensions of components may be exaggerated to effectively explain the technical content.

[0029] The terms and words used in this specification and claims should not be interpreted in a limited way to their ordinary or dictionary meanings, but should be interpreted in a way that corresponds to the technical idea of the present invention, in accordance with the principle that the inventor can appropriately define the concept of the terms himself / herself in order to explain the invention in the best way.

[0030] In this specification, terms indicating directions such as up and down are used, but these terms are used for the convenience of explanation, and it will be obvious to those having ordinary knowledge in the technical field to which this invention pertains (hereinafter referred to as "persons skilled in the art") that they may differ depending on the position of the object in question, the position of the observer, etc.

[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 equivalent and modified embodiments that can be substituted for them at the time of this application.

[0032] FIG. 1 is a diagram showing the appearance of a battery pack 10 according to an embodiment of the present invention, and FIG. 2 is a diagram showing the components of the battery pack 10 according to an embodiment of the present invention in an exploded view.

[0033] 1 and 2, a battery pack 10 according to an embodiment of the present invention may include a battery module 100 and a pack case 200.

[0034] Although the battery module 100 is not illustrated in detail, the battery module 100 may include a battery cell. A plurality of battery cells may be provided. The battery cell may refer to a secondary battery. The battery cell may include an electrode assembly, an electrolyte, a battery case that houses the electrode assembly and the electrolyte, and a pair of electrode leads that are connected to the electrode assembly and extend to the outside of the battery case. The battery cell may be, for example, a pouch-type secondary battery. However, secondary batteries of other shapes, such as cylindrical batteries and prismatic batteries, may also be used as the battery cell of the present invention.

[0035] The pack case 200 may have an internal space. The pack case 200 may house the battery modules 100 in the internal space. The pack case 200 may have a substantially rectangular parallelepiped shape.

[0036] The pack case 200 may include a case body 210 and an enclosure 220 .

[0037] The case body 210 may have an internal space. The case body 210 may have an opening on at least one of one side and the other side opposite the one side. For example, referring to FIG. 2, the case body 210 may have a substantially hollow rectangular prism shape and include four plates. In this case, at least a portion of each plate constituting the case body 210 may be integrally formed with one another. Alternatively, the four plates may be manufactured separately and then joined together by welding, bolting, or the like. In this case, the openings may be provided in the positive and negative directions of the X-axis.

[0038] The enclosure 220 may be configured to prevent the opening from being exposed to the outside of the pack case 200. The enclosure 220 may be coupled to the case body 210. The enclosure 220 may be configured to seal the opening. For example, referring to FIG. 2 , the enclosure 220 may be located at the openings provided in the positive and negative directions of the X-axis of the case body 210, and may be coupled to the case body 210.

[0039] By sealing the opening with such an enclosure 220 according to one embodiment of the present invention, the airtight performance of the pack case 200 can be ensured, and unintentional leakage of gas or flames to the outside of the pack case 200 can be effectively prevented in the event of a thermal event in the battery module 100.

[0040] The enclosure 220 of the present invention will be described in more detail below.

[0041] FIG. 3 is a diagram illustrating a coupling relationship between a case body and an enclosure included in a battery pack according to an embodiment of the present invention.

[0042] 3, the enclosure 220 may include a protrusion 222. The case body 210 may include a recess 211.

[0043] Enclosure 220 may have, on its outer surface coupled to case body 210, protrusion 222 that protrudes toward the inner surface of case body 210. For example, protrusion 222 may be formed to protrude in the negative direction of the Z axis from the outer surface of enclosure 220 located in the negative direction of the Z axis toward the inner surface of case body 210.

[0044] Case body 210 may include a recess 211 formed on the inner surface thereof to correspond to protrusion 222. Recess 211 may accommodate protrusion 222. For example, recess 211 may be recessed in the negative direction of the Z axis so as to accommodate protrusion 222 from the inner surface of case body 210 located in the negative direction of the Z axis.

[0045] The protrusion 222 of the enclosure 220 is fitted into the recess 211 of the case body 210, whereby the case body 210 and the enclosure 220 can be coupled to each other.

[0046] This configuration of one embodiment of the present invention can significantly improve resistance to internal pressure of the battery pack 10. During a thermal event in the battery module 100, pressure may increase in the internal space of the pack case 200 of the battery pack 10 due to gas, flame, or the like. In one embodiment of the present invention, due to the above-described coupling structure that ensures airtightness between the enclosure 220 and the case body 210, even if the internal pressure inside the battery pack 10 increases, the battery pack 10 can have strong resistance to shear stress caused by the internal pressure. In addition, this configuration of one embodiment of the present invention can improve not only the airtightness performance of the battery pack 10 but also the watertightness performance. Furthermore, the components of the protrusion 222 and the recess 211 increase the coupling area between the case body 210 and the enclosure 220, thereby increasing the coupling strength.

[0047] FIG. 4 is an enlarged view of a part of FIG.

[0048] Referring to FIG. 4, the enclosure 220 may include a cover portion 221 and a protrusion portion 222 .

[0049] The cover portion 221 may be configured to cover the opening portion, and may have a substantially rectangular parallelepiped shape to correspond to the opening portion.

[0050] The protrusion 222 may be formed on at least one end (in the negative direction of the Z axis) of both end portions of the cover portion 221. The protrusion 222 may protrude toward the inner surface of the case main body 210. Specifically, the protrusion 222 may extend so as to protrude a predetermined length toward the inner surface of the case main body 210. The enclosure 220 and the case main body 210 may be coupled to each other at at least one end (in the negative direction of the Z axis) where the protrusion 222 is formed.

[0051] Here, the protruding length and / or protruding thickness of the protrusion 222 can be determined according to a predetermined level of resistable internal pressure. Similarly, the recessed length or recessed thickness of the recess 211 coupled with the protrusion 222 can also be determined according to a predetermined level of resistable internal pressure.

[0052] In one embodiment of the present invention, such a configuration allows the structure of battery pack 10 to be designed to match the timing at which venting should occur based on the internal pressure by adjusting the height and / or thickness of protrusion 222 and recess 211 according to the level of internal pressure that can be resisted.

[0053] The protrusion 222 may be formed in a tapered shape from at least one end (negative direction of the Z axis) of the cover portion 221 toward the inner surface of the case main body 210. For example, the protrusion 222 may be configured to have a substantially V-shaped cross section.

[0054] According to this configuration of one embodiment of the present invention, the area where each of the protrusions 222 is coupled to the case body 210 is increased, and the coupling strength between the case body 210 and the enclosure 220 can be increased.

[0055] 3, the protrusions 222 may be formed on both ends of the cover portion 221 (the ends located in the positive direction of the Z axis and the negative direction of the Z axis). The enclosure 220 may be coupled to the case body 210 at both ends where the protrusions 222 are formed. When the protrusions 222 are formed on both ends, it is possible to increase the internal pressure resistance compared to when the protrusions 222 are formed on one end.

[0056] FIG. 5 is a diagram illustrating an enclosure included in a battery pack according to one embodiment of the present invention.

[0057] 6, protrusions 222 may be provided at one corner (negative direction of the Z axis) and the other corner (positive direction of the Z axis) of enclosure 220. Protrusions 222 are configured in two pairs (a pair of protrusions 222 (222a, 222b) and a pair of protrusions 222 (222c, 222d)), and one pair may be provided at one corner and the other corner of enclosure 220. The pair of protrusions 222 provided at one corner and the other corner, respectively, may be arranged at a predetermined distance from each other in the width direction (X-axis direction) of enclosure 220. For example, a pair of protrusions 222 (222c, 222d) provided at one corner (a corner on the outer surface located in the negative direction of the Z axis) may be spaced a predetermined distance apart in the X-axis direction, and a pair of protrusions 222 (222a, 222b) provided at the other corner (a corner on the outer surface located in the positive direction of the Z axis) may also be spaced a predetermined distance apart in the X-axis direction.

[0058] This configuration of one embodiment of the present invention makes it possible to easily couple case body 210 and enclosure 220. If protrusion 222 is located on the inside rather than at a corner, protrusion 222 needs to be fitted into case body 210. However, if protrusion 222 is located at a corner, only protrusions 222a and 222c provided at the inside corners located inside battery pack 10 are fitted into case body 210, and protrusions 222b and 222d located at the outside corners are engaged with recessed portions 211, thereby allowing case body 210 and enclosure 220 to be coupled together.

[0059] FIG. 6 is a diagram illustrating some components included in a battery pack according to one embodiment of the present invention.

[0060] Referring to FIG. 6 and previously described FIG. 2, the battery pack 10 may include a seal member 300.

[0061] The seal member 300 may be interposed between the enclosure 220 and the case body 210. The seal member 300 may be provided along the width direction (Y-axis direction) of the case body 210. The seal member 300 may be disposed between a pair of protrusions 222 provided at one corner (negative direction of the Z-axis) and the other corner (positive direction of the Z-axis), respectively.

[0062] The enclosure 220 may include a seal groove 223 in which the seal member 300 is disposed. The seal groove 223 may have a shape recessed from the inner surface of the enclosure 220 to correspond to the shape of the seal member 300.

[0063] According to this configuration of one embodiment of the present invention, the sealing member 300 can increase the bonding strength between the case body 210 and the enclosure 220. In particular, if a gap occurs between the case body 210 and the enclosure 220 due to assembly tolerances or the like, the gap may cause a decrease in the watertightness and airtightness of the battery pack 10, but this can be prevented by the sealing member 300.

[0064] FIG. 7 is another diagram showing some components included in a battery pack 10 according to another embodiment of the present invention.

[0065] 7 , the sealing member 300 may be provided between the end of each protrusion 222 and the case body 210. For example, as described above, the sealing member 300 may include a sealing member 300a provided between a pair of protrusions 222 provided at one corner and the other corner, a sealing member 300b provided at an end of the protrusion 222 adjacent to the inside of the battery pack 10, and a sealing member 300c provided at an end of the protrusion 222 adjacent to the outside of the battery pack 10.

[0066] In one embodiment of the present invention, by providing a plurality of sealing members 300a to 300c, the bonding strength between the case body 210 and the enclosure 220 can be increased, and watertightness and airtightness can be further ensured.

[0067] FIG. 8 is a diagram showing some components of a battery pack according to another embodiment of the present invention, and FIG. 9 is a cross-sectional view of a portion of the configuration included in the battery pack of FIG.

[0068] 8 and 9, the battery pack 10 may include an additional seal member 400.

[0069] The additional seal member 400 may be provided between the enclosure 220 and the case body 210, particularly along the height direction (Z-axis direction) of the case body 210. The case body 210 may include a seal groove 212 in which the additional seal member 400 is disposed. The seal groove 212 may have a shape recessed from the inner surface of the case body 210 to correspond to the shape of the additional seal member 400.

[0070] The seal member 300 and the additional seal member 400 may be connected together and configured to substantially entirely surround the enclosure 220 .

[0071] According to this configuration of one embodiment of the present invention, the multiple sealing members 300, 400 can improve the watertightness and airtightness of the battery pack 10 at all four edges (boundaries) between the case body 210 and the enclosure 220.

[0072] 1 to 5, the battery pack 10 may include a vent device 500. The vent device 500 may be provided in the enclosure 220. The vent device 500 may be configured to exhaust gas generated from the battery module 100 to the outside of the pack case 200. The vent device 500 is closed in a normal (normal) state, but may be configured to be openable in response to changes in pressure, temperature, etc.

[0073] The vent device 500 can be opened to allow flames, gas, and the like inside the pack case 200 to be discharged to the outside when the internal pressure of the pack case 200 reaches or exceeds a predetermined allowable internal pressure. The interconnected structure between the protrusions 222 of the enclosure 220 and the recesses 211 of the case body 210 can prevent unintended flame and gas leakage that may occur before the allowable internal pressure is reached. As described above, the protrusions 222 of the enclosure 220 are double-engaged with the edge sides of the case body 210. Therefore, even if the enclosure 220 is deformed due to expansion before the allowable internal pressure is reached, the edge sides of the case body 210 can effectively block gas, flame, and the like inside the pack case 200. Therefore, even if the enclosure 220 is deformed before the allowable internal pressure is reached, the double-engaged structure of the protrusions 222 can effectively prevent flame and gas leakage, particularly leakage from the edge sides of the case body 210.

[0074] FIG. 10 is another view showing the coupling relationship between the case body and the enclosure included in the battery pack according to an embodiment of the present invention.

[0075] 10, a plurality of protrusions 222 may be provided. For example, three protrusions 222 may be provided on each end of the enclosure 220.

[0076] According to this configuration of an embodiment of the present invention, the coupling area between the case body 210 and the enclosure 220 can be further increased, thereby increasing the coupling strength. Furthermore, when the internal pressure of the battery pack 10 increases and venting occurs, the number of gas transfer paths between the case body 210 and the enclosure 220 increases. Therefore, even if the coupling between the case body 210 and the enclosure 220 in a portion adjacent to the interior of the battery pack 10 is temporarily released, the gas can be vented through another path, such as a vent device, and the case body 210 and the enclosure 220 can be recoupled. In other words, the resistance of the battery pack 10 to internal pressure can be further increased.

[0077] FIG. 11 is a diagram illustrating a vehicle according to one embodiment of the present invention.

[0078] 11, an automobile 1 according to an embodiment of the present invention may include a battery pack 10. The automobile 1 may be a hybrid automobile 1 or an electric automobile 1. In addition to the battery pack 10, the automobile 1 according to an embodiment of the present invention may further include various other components included in the automobile 1. For example, in addition to the battery pack 10 according to the present invention, the automobile 1 according to an embodiment of the present invention may further include a vehicle body, a motor, a control device such as an electronic control unit (ECU), and the like.

[0079] While the present invention has been described above with reference to the accompanying drawings, focusing on preferred embodiments, it will be apparent to those skilled in the art that numerous and obvious modifications can be made from such description without departing from the scope of the present invention. Therefore, the scope of the present invention should be construed by the claims which are set forth to include such various modified embodiments. [Explanation of symbols]

[0080] 10 Battery Pack 100 Battery Module 200 pack case 210 Case body 220 Enclosure

Claims

1. at least one battery module; a pack case that houses the battery module in its internal space; Including, The pack case is a case body having the internal space and configured to have an opening on at least one of one side and another side opposite to the one side; an enclosure configured to be coupled to the case body to seal the opening so as to prevent the opening from being exposed to the outside of the pack case; Including the battery pack.

2. the enclosure has a protrusion on an outer surface coupled to the case body that protrudes toward an inner surface of the case body, The battery pack according to claim 1 , wherein the case body has a recess formed on an inner surface thereof to correspond to the protrusion.

3. the enclosure includes a cover portion that covers the opening, The battery pack according to claim 2 , wherein the protrusion is formed on at least one of both end portions of the cover portion and protrudes toward an inner surface of the case body.

4. 4. The battery pack according to claim 3, wherein the protrusions are formed at both end portions of the cover portion and extend from both of the one end and the other end of the cover portion so as to protrude a predetermined length toward the inner surface of the case body.

5. The battery pack according to claim 3 , wherein the protrusion is tapered from at least one end of the cover toward the inner surface of the case body.

6. The battery pack according to claim 4 , wherein the protrusion has a V-shaped cross section.

7. the enclosure has a plate shape and is coupled to the case body on one side and the other side; The battery pack according to claim 2 , wherein the protrusions are provided at one corner and the other corner of the enclosure.

8. The protrusions are configured in two pairs, one pair provided at one corner and the other corner of the enclosure, 8. The battery pack according to claim 7, wherein the pair of protrusions provided at the one corner and the other corner, respectively, are arranged at a predetermined distance from each other in the width direction of the enclosure.

9. The battery pack according to claim 8 , further comprising a seal member interposed between the enclosure and the case body.

10. The battery pack according to claim 9 , wherein the sealing member is disposed between a pair of protrusions provided at the one corner and the other corner, respectively.

11. The battery pack according to claim 1 , further comprising a vent device provided in the enclosure and configured to exhaust gas generated from the battery module to the outside of the pack case.

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

Images