Battery pack and device including the same

Abstract

A battery pack according to one embodiment of the present invention includes a plurality of battery modules, a barrier beam disposed between adjacent battery modules among the plurality of battery modules, and a housing that accommodates the plurality of battery modules and the barrier beam.

Description

Technical Field

[0001] Cross-reference to related applications This application claims the benefit of priority based on Korean Patent Application No. 10-2020-0044967 filed on April 14, 2020, and all the contents disclosed in the document of the Korean Patent Application are incorporated herein by reference in their entirety.

[0002] The present invention relates to a battery pack and a device including the same, and more particularly, to a battery pack with improved safety and a device including the same.

Background Art

[0003] Secondary batteries, which are highly applicable according to product groups and have electrical characteristics such as high energy density, are widely applied not only to portable devices but also to electric vehicles or hybrid vehicles driven by an electric drive source, power storage devices, etc. Such secondary batteries are attracting attention as a new energy source for environmental friendliness and improvement of energy efficiency because they can significantly reduce the use of fossil fuels and produce no by-products from energy use.

[0004] Currently commercialized secondary batteries include nickel-cadmium batteries, nickel-metal hydride batteries, nickel-zinc batteries, lithium secondary batteries, etc. Among these, lithium secondary batteries are in the spotlight because they hardly have a memory effect compared to nickel-based secondary batteries, can be freely charged and discharged, have a very low self-discharge rate, and have a high energy density.

[0005] Such lithium secondary batteries mainly use lithium-based oxides and carbon materials as the positive electrode active material and the negative electrode active material, respectively. A lithium secondary battery includes an electrode assembly in which a positive electrode plate and a negative electrode plate, each coated with such a positive electrode active material and a negative electrode active material, are arranged with a separator interposed therebetween, and an exterior material that hermetically stores the electrode assembly together with an electrolytic solution, that is, a battery case.

[0006] Generally, lithium secondary batteries can be classified into a prismatic secondary battery in which an electrode assembly is installed in a metal can and a pouch-type secondary battery in which an electrode assembly is installed in a pouch made of an aluminum laminate sheet, depending on the shape of the exterior material.

[0007] In the case of secondary batteries used in small devices, 2 to 3 battery cells are arranged. However, in the case of secondary batteries used in medium- and large-sized devices such as automobiles, a battery module in which a large number of battery cells are electrically connected is used. In such a battery module, the capacity and output are improved by forming a battery cell laminate in which a large number of battery cells are connected in series or parallel to each other. In addition, a plurality of battery modules can be mounted together with various control and protection systems such as a BMS (Battery Management System) and a cooling system to form a battery pack.

[0008] Since the battery pack has a structure in which a large number of battery modules are combined, if some of the battery modules are overvoltage, overcurrent, or overheat, the safety and operating efficiency of the battery pack may become a problem. In particular, the capacity of the battery pack tends to gradually increase in order to improve the driving range, and accordingly, the internal energy of the pack also increases. In this situation, it is necessary to design a structure that satisfies the strengthened safety standards and ensures the safety of the vehicle and the driver. For this reason, there is a growing need for a structure that can suppress the transfer between modules so as to prevent internal thermal runaway in particular and minimize the damage even if it occurs.

Summary of the Invention

Problems to be Solved by the Invention

[0009] An embodiment of the present invention aims to provide a battery pack capable of suppressing the transfer between modules so as to minimize the damage even if some of the battery modules are overvoltage, overcurrent, or overheat in the battery.

[0010] However, the problems to be solved by the embodiments of the present invention are not limited to the problems described above, and can be variously extended within the scope of the technical idea included in the present invention.

Means for Solving the Problems

[0011] A battery pack according to an embodiment of the present invention includes a plurality of battery modules, a barrier beam disposed between adjacent battery modules among the plurality of battery modules, and a housing that houses the plurality of battery modules and the barrier beam.

[0012] The barrier beam can include a vertical beam extending along a first direction and a horizontal beam extending along a second direction orthogonal to the first direction.

[0013] The housing can include a lower housing including a bottom surface on which the plurality of battery modules are disposed and side surfaces extending upward from the periphery of the bottom surface, and at least one upper cover that covers at least a part of the upper portion of the lower housing.

[0014] The battery pack can further include at least one coupling member that couples the upper cover and the barrier beam.

[0015] The upper cover can include a recessed portion that is recessed toward the barrier beam at a portion where the upper cover is coupled to the barrier beam by the coupling member.

[0016] The coupling member can be a bolt and a nut.

[0017] The battery pack can further include a barrier frame that is located between the plurality of battery modules and the side surface of the lower housing and is disposed along the periphery of the plurality of battery modules.

[0018] Each side of the barrier frame can be in a tubular form with an empty interior.

[0019] The material of the barrier beam can be steel.

[0020] A device according to another embodiment of the present invention can include the at least one battery pack.

Advantages of the Invention

[0021] According to an embodiment of the present invention, even if some battery modules are overvoltage, overcurrent or overheated in the battery, high-temperature, high-pressure gas and flame can be blocked from propagating to surrounding modules, so that the damage can be minimized, and the safety of the battery pack can be improved.

Brief Description of the Drawings

[0022]

Figure 1

Figure 2

Figure 3

Figure 4

Modes for Carrying Out the Invention

[0023] Hereinafter, various embodiments of the present invention will be described in detail with reference to the accompanying drawings so that those having ordinary knowledge in the technical field to which the present invention pertains can easily implement them. The present invention can be realized in various different forms and is not limited to the embodiments described herein.

[0024] To clearly explain the present invention, parts that are unnecessary for the explanation are omitted, and the same reference numerals are given to the same or similar components throughout the specification.

[0025] Also, the sizes and thicknesses of the respective components shown in the drawings are arbitrarily shown for convenience of explanation, and the present invention is not necessarily limited to the illustrated locations. In the drawings, the thicknesses are enlarged to clearly represent a plurality of layers and regions. And in the drawings, for convenience of explanation, the thicknesses of some layers and regions are exaggeratedly shown.

[0026] Also, when a part such as a layer, film, region, or plate is "above" another part, this includes not only the case where it is directly above the other part but also the case where there are other parts in between. Conversely, when a part is "directly above" another part, it means that there are no other parts in between. Also, being "above" a reference part means being located above or below the reference part, and does not necessarily mean being located "above" in the direction opposite to gravity.

[0027] Also, throughout the specification, when a part "includes" a certain component, this means that other components are not excluded and other components can be further included, unless there is a contrary description.

[0028] Also, throughout the specification, when it is said "on a plane", this means when the target part is viewed from above, and when it is said "in a cross-section", this means when the cross-section obtained by vertically cutting the target part is viewed from the side.

[0029] Hereinafter, a battery pack according to an embodiment of the present invention will be described.

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

[0031] Referring to FIG. 1, a battery pack 10 according to an embodiment of the present invention includes a plurality of battery modules 100 and a barrier beam 300 disposed between adjacent battery modules among the plurality of battery modules 100. The plurality of battery modules 100 and the barrier beam 300 can be mounted on a pack tray 200 and housed in a housing 400. The housing 400 can include a lower housing 410 that houses the pack tray 200 and an upper cover 420 that is coupled to the lower housing 410 and covers the upper portion of the battery module 100.

[0032] The lower housing 410 can include a bottom surface on which the plurality of battery modules 100 and the pack tray 200 are disposed and side surfaces that extend upward from the periphery of the bottom surface. With such a configuration, as shown in FIG. 1, the upper portion of the lower housing 410 has an open state. A plurality of battery modules 100, a barrier beam 300, a pack tray 200, and various control and protection systems such as other BMS (Battery Management System) and a cooling system are mounted inside the lower housing 410 and can be coupled so that the open upper portion is covered by the upper cover 420.

[0033] As shown in FIG. 1, the upper cover 420 may have a structure divided into two parts, may be integrally formed, or may have a structure divided into more than two parts. Further, an additional case cover or the like that further covers the upper cover 420 may be provided, and it is not particularly limited. When the upper cover 420 is formed across a plurality of battery modules 100, as shown in FIG. 1, it may have a recessed portion 422 at a portion corresponding to the barrier beam 300 between the battery modules 100. The recessed portion 422 causes the upper cover 420 to come into contact with the barrier beam 300, whereby the portion where one battery module 100 is disposed can be spatially separated. By providing the upper cover 420 in this way and having the recessed portion 422 at a portion corresponding to the barrier beam 300 in the upper cover 420, even if overvoltage, overcurrent, or overheating (thermal problem) occurs in any one of the battery modules 100, generating high-temperature, high-pressure gas and flames, it can be blocked from being transmitted to the adjacent battery module 100 through the upper space. Also, during normal times when such thermal problems do not occur, the upper cover 420 disposed adjacent to the upper surface of the battery module 100 serves as a structure that suppresses the vibration of the battery module 100, thereby improving the stability of the entire battery pack 10.

[0034] Between adjacent battery modules 100 among the plurality of battery modules 100, a barrier beam 300 is disposed. The barrier beam 300 is a columnar structure made of a material such as steel, and as shown in FIG. 1, in a battery pack 10 including, for example, four battery modules 100, the vertical beam 310 and the horizontal beam 320 may be arranged to intersect and have a cross shape. Such a form may be integrally formed, or the horizontal beams 320 formed short on the left and right sides of one vertical beam 310 may be joined, and it is not particularly limited. Also, when the number of battery modules 100 increases, it may be arranged in a lattice form that can partition all between the battery modules 100.

[0035] The barrier beam 300 can isolate the battery module 100 from adjacent modules and arrange it in an isolated state. As a result, even if overvoltage, overcurrent, or overheating (thermal problem) occurs in any one battery module 100, generating high-temperature, high-pressure gas and flames, the barrier beam 300 can block their transmission to surrounding modules, thus preventing additional occurrences of thermal problems. Also, in normal times when such thermal problems do not occur, the barrier beam 300 can play the role of a structure that stably supports the battery module 100, thereby improving the rigidity of the entire battery pack 10.

[0036] On the other hand, the barrier frame 500 can be arranged along the periphery of the entire plurality of battery modules 100. That is, the barrier frame 500 can be arranged to surround the entire periphery of the plurality of battery modules 100 between the plurality of battery modules 100 and the side surface of the lower housing 410. The barrier frame 500 can be coupled to the upper cover 420 at its upper part. Thereby, the space where one battery module 100 is arranged can be blocked from other parts by the combination of the barrier beam 300, the barrier frame 500, and the upper cover 420 to form an isolated independent space.

[0037] Also, the barrier frame 500 can be formed in a tubular form with an empty interior. In this case, a connecting hole can be provided so that the passage inside the barrier frame 500 communicates with the battery module 100, and the high-temperature, high-pressure gas and flames generated in the battery module 100 where a thermal problem has occurred can be moved along a defined path and discharged to the outside while blocking the influence on other modules.

[0038] The plurality of battery modules 100, the barrier beam 300, and the barrier frame 500 can be mounted on the pack tray 200 and can be fixed to the pack tray 200 by fixing means as needed. The battery module 100, the barrier beam 300, and the barrier frame 500 can be accommodated in the lower housing 410 in a state of being mounted on the pack tray 200.

[0039] Hereinafter, the connection portion between the upper cover and the barrier beam in the battery pack according to an embodiment of the present invention will be described in more detail.

[0040] FIG. 2 is a drawing showing an enlarged cross section of the connection portion between the upper cover and the barrier beam in the battery pack according to an embodiment of the present invention.

[0041] Referring to FIGS. 1 and 2, the upper cover 420 is provided with a recessed portion 422 in a region corresponding to the barrier beam 300, and is formed such that the inner surface of the recessed portion 422 contacts the barrier beam 300. With the recessed portion 422 and the barrier beam 300 in contact, the upper cover 420 and the barrier beam 300 can be fixed by coupling a bolt 431 and a nut 432 through holes formed in the upper cover 420 and the barrier beam 300. Such fixing means is not particularly limited, and can also be coupled by welding or an adhesive. By coupling the upper cover 420 and the barrier beam 300 at the recessed portion 422 in this way, the regions partitioned by the barrier beam 300 can be blocked and isolated from each other even at the upper part. Also, although not shown in the drawing, by coupling the barrier frame 500 and the upper cover 420 in the same manner at the overlapping portion, each battery module 100 can be accommodated in a blocked and isolated space. As a result, the high-temperature, high-pressure gas and flame generated in one battery module 100 can be blocked in all directions and the propagation to the adjacent battery module 100 can be surely blocked. Further, since the battery module 100 can be stably supported by the structure when the upper cover 420 and the barrier beam 300 are fixed by the fixing means, the stability of the battery pack 10 can be improved even during normal times.

[0042] Hereinafter, when problems such as overvoltage, overcurrent, or overheating occur in some battery modules in the battery pack, the propagation of high-temperature, high-pressure gas and flame will be described together with a comparative example.

[0043] FIG. 3 is a diagram schematically showing a transmission path when thermal runaway occurs in some modules of a battery pack according to an embodiment of the present invention, and FIG. 4 is a diagram schematically showing a transmission path when thermal runaway occurs in some modules of a battery pack according to a comparative example.

[0044] As shown in FIG. 3, according to the embodiment of the present invention including the barrier beam 300 disposed between the battery modules 100, even if high-temperature, high-pressure gas and flames are generated due to a thermal problem in some of the battery modules 100, the gas and flames are not propagated to the adjacent battery modules 100, but are blocked by the barrier beam 300 and only affect the inside thereof. Therefore, the occurrence of additional thermal problems can be prevented.

[0045] On the contrary, in the case of the conventional battery pack 10 to which the structure of such a barrier beam 300 is not applied, as shown in FIG. 4, the venting gas (high-temperature, high-pressure gas and flames) generated in the first module is randomly transmitted to the entire second to fourth modules, and eventually, all the modules inside the battery pack 10 are exposed to the risk of temperature rise and chain reaction of additional thermal runaway.

[0046] Thus, according to an embodiment of the present invention, by providing the barrier beam 300, it acts as a structure that stably supports the battery module 100 during normal times, and can block the propagation of high-pressure venting gas (high-temperature, high-pressure gas and flames) generated when a thermal problem occurs inside the battery pack 10 to the adjacent battery modules 100, thereby preventing the spread to the surrounding modules. In addition, by coupling such a barrier beam 300 with the upper cover 420 covering the battery module 100, an isolated individual space is provided for each battery module 100, and the spread to the surrounding modules can be more reliably prevented. At the same time, the upper cover 420 can also serve as a structure for suppressing the vibration of the battery module 100, and the stability of the battery pack 10 can be further improved.

[0047] The above-described battery module and the battery pack including the same can be applied to various devices. Such devices can be applied to transportation means such as electric bicycles, electric vehicles, and hybrid vehicles, but the present invention is not limited thereto, and the present invention is applicable to various devices that can use the battery module and the battery pack including the same, and this also belongs to the scope of rights of the present invention.

[0048] Although the preferred embodiments of the present invention have been described in detail above, the scope of rights of the present invention is not limited thereto, and various modifications and improvements made by those skilled in the art using the basic concept of the present invention defined in the claims also belong to the scope of rights of the present invention.

Explanation of Reference Numerals

[0049] 10: Battery pack 100: Battery module 200: Pack tray 300: Barrier beam 310: Vertical beam 320: Horizontal beam 400: Housing 410: Lower housing 420: Upper cover 422: Depression 500: Barrier frame

Claims

1. A plurality of battery modules, Among the plurality of battery modules, a barrier beam disposed between adjacent battery modules to block the adjacent battery modules from each other, and A housing that houses the plurality of battery modules and the barrier beam, including a bottom surface on which the plurality of battery modules are disposed, and a lower housing including side surfaces extending upward from the periphery of the bottom surface, and at least one upper cover covering at least a part of the upper part of the lower housing, Including, The upper cover includes a recessed portion recessed toward the barrier beam at a portion where the upper cover is coupled to the barrier beam, A battery pack in which the upper surface of the barrier beam and the lower surface of the recessed portion are in surface contact, so that the spaces in which the adjacent battery modules are respectively disposed are spatially discontinuously separated from each other.

2. The battery pack according to claim 1, wherein the barrier beam includes a vertical beam extending along a first direction and a horizontal beam extending along a second direction orthogonal to the first direction.

3. The battery pack according to claim 1 or 2, further including at least one coupling member that couples the upper cover and the barrier beam.

4. The battery pack according to claim 3, wherein the recessed portion recesses toward the barrier beam at a portion where the recessed portion is coupled to the barrier beam by the coupling member.

5. The battery pack according to claim 3 or 4, wherein the coupling member is a bolt and a nut.

6. The battery pack according to any one of claims 1 to 5, further including a barrier frame located between the plurality of battery modules and the side surface of the lower housing and disposed along the periphery of the plurality of battery modules.

7. The battery pack according to claim 6, wherein each side of the barrier frame is in a tubular form with an empty interior.

8. The battery pack according to any one of claims 1 to 7, wherein the material of the barrier beam is steel.

9. A device including at least one battery pack according to any one of claims 1 to 8.

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