Battery pack and device including same

Abstract

A battery pack according to an embodiment of the present invention comprises: a plurality of battery modules; a pack frame that accommodates the plurality of battery modules; a plurality of inter-bus bars that electrically connect terminals of neighboring battery modules among the plurality of battery modules; and a heat-resistant cover disposed across the gap between the plurality of battery modules and covering the plurality of inter-bus bars.

Description

Battery pack and device including same

[0001] Cross-citation with related application(s)

[0002] This application claims the benefit of priority to Korean Patent Application No. 10-2024-0103823, filed August 5, 2024, the entire contents of which are incorporated herein by reference.

[0003] The present invention relates to a battery pack and a device including the same, and more particularly, to a battery pack and a device including the same that can effectively block thermal runaway while reducing weight and cost.

[0004] In modern society, the widespread use of portable devices like cell phones, laptops, camcorders, and digital cameras has fueled active development of technologies related to these devices. Furthermore, rechargeable secondary batteries are increasingly being used as power sources for electric vehicles (EVs), hybrid electric vehicles (HEVs), and plug-in hybrid electric vehicles (P-HEVs) to address air pollution caused by conventional gasoline-powered vehicles. This, in turn, heightens the need for further development of these batteries.

[0005] Currently commercialized secondary batteries include nickel cadmium batteries, nickel hydrogen batteries, nickel zinc batteries, and lithium secondary batteries. Among these, lithium secondary batteries are receiving attention for their advantages of being able to charge and discharge freely, having a very low self-discharge rate, and having a high energy density, as they have almost no memory effect compared to nickel-based secondary batteries.

[0006] These lithium secondary batteries primarily use lithium oxide and carbon materials as the positive and negative electrode active materials, respectively. The lithium secondary battery comprises an electrode assembly comprising a positive electrode plate and a negative electrode plate, each coated with the positive and negative electrode active materials, with a separator interposed between them, and a battery case that seals and houses the electrode assembly together with an electrolyte.

[0007] In general, lithium secondary batteries can be classified into can-type secondary batteries in which the electrode assembly is built into a metal can and pouch-type secondary batteries in which the electrode assembly is built into a pouch of an aluminum laminate sheet, depending on the shape of the outer packaging material.

[0008] In the case of secondary batteries used in small devices, 2-3 battery cells are arranged, but in the case of secondary batteries used in medium to large devices such as automobiles, a battery module in which multiple battery cells are electrically connected is used. Such a battery module improves capacity and output by forming a battery cell stack by connecting multiple battery cells in series or parallel. One or more battery modules can be mounted together with various control and protection systems such as a battery management system (BMS), a battery disconnect unit (BDU), and a cooling system to form a battery pack.

[0009] A battery pack includes battery modules as a sub-concept, and a battery module includes battery cells as a sub-concept. Such a battery module may comprise a case housing multiple battery cells, or a battery cell assembly formed by stacking battery cells may be directly applied as a battery module to the battery pack. Furthermore, the number of battery cells in a battery module or the number of battery modules in a battery pack may vary depending on the output or capacity of the battery pack required for the electric vehicle.

[0010] However, in the case of these battery packs, one of the most important issues is safety. In particular, if a thermal event occurs in one of the multiple battery cells included in the battery pack, it is necessary to prevent the propagation of this thermal event to other battery cells and modules. To this end, a partition wall or the like may be provided between the battery modules or battery cell stacks to block heat transmission between the battery modules or battery cells. In the past, metal materials were used as the partition walls for rigidity, but this increased the weight and cost of the battery pack. In addition, when using metal partition walls, additional structures must be used to improve heat resistance and insulation between the battery modules or bus bars, which also increases the weight and cost and complicates the structure of the battery pack.

[0011] The problem to be solved by the present invention is to provide a battery pack and a device including the same, which can effectively reduce weight and cost by improving the partition structure between battery modules in a battery pack, while effectively preventing flame exposure between adjacent modules and improving space utilization efficiency with a simple structure.

[0012] The tasks of the present invention are not limited to the tasks mentioned above, and other tasks not mentioned will be clearly understood by those skilled in the art from the description below.

[0013] A battery pack according to one embodiment of the present invention for realizing the above task includes a plurality of battery modules, a pack frame accommodating the plurality of battery modules, a plurality of inter-bus bars electrically connecting terminals of neighboring battery modules among the plurality of battery modules, and a heat-resistant cover disposed across the plurality of battery modules and covering the plurality of inter-bus bars.

[0014] The above heat-resistant cover may include heat-resistant plastic.

[0015] The plurality of battery modules may be arranged in the row direction and the column direction, and the battery modules arranged in the row direction may be arranged such that the terminals included in each of the battery modules face each other, and the heat-resistant cover may be arranged to extend in the column direction across the terminals.

[0016] The heat-resistant cover may include a pair of side portions covering one side of the plurality of battery modules, a bottom portion connecting lower portions of the pair of side portions, and wing portions extending from the upper portions of each of the pair of side portions to cover a portion of the upper portions of the plurality of battery modules.

[0017] Each of the plurality of battery modules and the heat-resistant cover can be fixed to each other through a snap-fit ​​connection at the wing portion.

[0018] The above wing portion may include a plurality of snap holes forming the snap-fit ​​joint.

[0019] The battery pack may further include a plurality of snap pins inserted into the snap holes.

[0020] A plurality of connector holes are formed on each of the pair of side portions to expose connector terminals of each of the plurality of battery modules, and the plurality of connector holes on the pair of side portions may be arranged so as not to face each other.

[0021] The above battery pack may further include a long busbar disposed in a space between the pair of side portions.

[0022] The above battery pack may further include an upper cover covering a space between the pair of side portions of the heat-resistant cover.

[0023] The upper cover may include a plurality of joining holes, and the heat-resistant cover may include a plurality of joining hooks that join with the plurality of joining holes at a corner portion where the side portion and the wing portion meet.

[0024] The battery pack further includes a plurality of connection boxes arranged on top of some of the plurality of battery modules, and the long bus bar can electrically connect the connection boxes to the plurality of battery modules, or the plurality of connection boxes to each other.

[0025] The above heat-resistant cover may further include a plurality of ring portions arranged adjacent to each of the connector holes.

[0026] A device according to another embodiment of the present invention may include the battery pack.

[0027] A battery pack and a device including the same according to one embodiment of the present invention can reduce the weight and cost of the battery pack by improving the partition structure arranged between battery modules in the battery pack, and can also effectively prevent flame exposure between adjacent modules while efficiently utilizing space within the battery pack.

[0028] The effects of the present invention are not limited to the effects mentioned above, and other effects not mentioned will be clearly understood by those skilled in the art from the description of the claims.

[0029] Figure 1 is a perspective view showing a battery pack according to one embodiment of the present invention.

[0030] Figure 2 is an exploded perspective view showing a battery pack according to one embodiment of the present invention.

[0031] Figure 3 is a drawing showing the heat-resistant cover of Figure 1 separated.

[0032] Figure 4 is an enlarged perspective view of part A of Figure 1.

[0033] Figure 5 is an enlarged view of part A of Figure 1.

[0034] Figure 6 is a drawing showing part A of Figure 1 from above.

[0035] FIG. 7 is a drawing illustrating a battery pack according to another embodiment of the present invention.

[0036] Figure 8 is a drawing showing a state in which the upper cover is excluded from Figure 7.

[0037] Figure 9 is an enlarged view of part B of Figure 7.

[0038] Figure 10 is a drawing showing the heat-resistant cover and upper cover of Figure 7 in a disassembled state.

[0039] The embodiments described below are provided as examples to aid in understanding the invention, and it should be understood that the present invention can be implemented in various ways other than the embodiments described herein. However, when describing the present invention, if it is determined that a detailed description of a related known function or component may unnecessarily obscure the gist of the present invention, a detailed description and specific illustration thereof will be omitted. In addition, the attached drawings are not drawn to scale to aid in understanding the invention, and the dimensions of some components may be exaggerated.

[0040] The first and second terms used in this application may be used to describe various components, but the components should not be limited by the terms. The terms are used solely to distinguish one component from another.

[0041] In addition, the terminology used in this application is only used to describe specific embodiments and is not intended to limit the scope of the rights. The singular expression includes the plural expression unless the context clearly indicates otherwise. It should be understood that the terms "comprises," "consists of," or "consists of" in this application are intended to specify the presence of a feature, number, step, operation, component, part, or combination thereof described in the specification, but do not preclude the possibility of the presence or addition of one or more other features, numbers, steps, operations, components, parts, or combinations thereof.

[0042] Hereinafter, the configuration of a battery pack according to one embodiment of the present invention will be described with reference to FIGS. 1 to 6.

[0043] FIG. 1 is a perspective view showing a battery pack according to one embodiment of the present invention. FIG. 2 is an exploded perspective view showing a battery pack according to one embodiment of the present invention. FIG. 3 is a view showing the heat-resistant cover of FIG. 1 in a detached state. FIG. 4 is a perspective view showing an enlarged portion A of FIG. 1. FIG. 5 is a view showing an enlarged portion A of FIG. 1. FIG. 6 is a view showing a portion A of FIG. 1 from above.

[0044] Referring to FIGS. 1 and 2, a battery pack (10) according to one embodiment of the present invention includes a plurality of battery modules (200), a pack frame (100) that accommodates the plurality of battery modules (200), a plurality of inter-bus bars (500) that electrically connect neighboring battery modules (200) among the plurality of battery modules (200), and a heat-resistant cover (300) that is arranged across the plurality of battery modules (200) and is formed to cover the inter-bus bars (500).

[0045] The pack frame (100) accommodates a plurality of battery modules (200). The pack frame (100) may include a plurality of module areas corresponding to the sizes of the battery modules (200), and the plurality of battery modules (200) may be respectively positioned in the plurality of module areas. According to the present embodiment, the plurality of battery modules (200) may be arranged in two rows along the stacking direction of the battery cells, but the present invention is not limited thereto, and an appropriate number may be arranged as needed. In particular, in the case of battery modules (200) adjacent in the row direction (x direction), the longitudinal ends of the battery modules (200) are arranged to face each other, and at this time, components that can electrically connect each battery module (200) to an external component, such as a terminal (210, illustrated in FIG. 4), a connector (220, illustrated in FIG. 4), etc., may be arranged at the longitudinal ends. In addition, in this embodiment, the pack frame (100) is exemplified as a simple plate shape, but the pack frame (100) may be a cooling plate with a cooling path arranged inside, or may be a venting plate with a venting path arranged inside. In addition, it may have a structure in which the cooling path and the venting path are arranged together, and various structures may be applied as a battery pack.

[0046] Each battery module (200) may include a battery cell stack (not shown) formed by stacking a plurality of battery cells. The battery cell is a secondary battery and may be formed as a pouch-type secondary battery, but is not particularly limited thereto. The battery cell may be formed in a plurality of pieces, and the plurality of battery cells may be stacked to be electrically connected to each other to form a battery cell stack. Each of the plurality of battery cells may include an electrode assembly, a battery case, and an electrode lead protruding from the electrode assembly. The battery cell stack may be accommodated in a module frame or the like with the electrode leads protruding, and a busbar frame and an end plate may be coupled to the protruding electrode leads. However, this is an exemplary configuration and is not limited thereto. When forming a battery pack, a moduleless type may be formed in which the battery cell stack and the busbar frame are coupled without including a module frame, and the battery pack is directly formed, but is not particularly limited thereto.

[0047] Referring to FIGS. 4 and 5, each battery module (200) may include a terminal (210) and a connector (220) for electrically connecting to an external configuration. The terminal (210) and the connector (220) may be exposed to the outside of the battery module (200) without being covered by an end plate. The terminal (210) may be electrically connected to neighboring battery modules (200) by an inter-bus bar (500) when a plurality of battery modules (200) constitute a battery pack (10).

[0048] The inter-bus bar (500) is formed in a form extending in the y-axis direction as illustrated in FIG. 4, and can be coupled to the terminals (210) of the battery modules (200) at both ends. Accordingly, it can be placed between neighboring battery modules (200) in the y-axis direction in the drawing, and electrically connect them. In addition, as described below, since the inter-bus bar (500) is covered by a heat-resistant cover (300), it can be protected from flames even if flames occur.

[0049] A heat-resistant cover (300) is formed across the battery modules (200) that are adjacent in the row direction, i.e., the x-axis direction, among the plurality of battery modules (200). That is, as illustrated in FIGS. 1 and 2, the heat-resistant cover (300) is formed to extend in the y-axis direction. The heat-resistant cover (300) is formed to block the battery modules (200) that face each other along the space between the plurality of battery modules (200). The heat-resistant cover (300) may be formed of heat-resistant plastic, such as heat-resistant silicone. This prevents flames or gases from spreading to the battery module (200) on the opposite side when thermal runaway occurs in any one of the plurality of battery modules (200). In particular, in one embodiment of the present invention, by eliminating a heavy bulkhead made of a metal material or the like and applying a heat-resistant cover (300) made of heat-resistant plastic, the weight of the entire battery pack (10) can be reduced, and the cost can also be reduced. In addition, when a bulkhead made of a material such as metal is applied, since the structure is not insulated, an additional structure is required for insulation from adjacent components, and additional insulating components are required to secure space for connecting busbars, etc., which causes the structure to become complicated and the cost to increase. However, in the present invention, by using only a heat-resistant cover (300) made of a heat-resistant plastic material, it is possible to provide an insulated space as well as act as a bulkhead against flames, etc., thereby reducing the number of components and efficiently utilizing space. In addition, since the inter-busbar (500) is coupled to the battery module (200) before the heat-resistant cover (300) is coupled, the heat-resistant cover (300) is mounted to cover the inter-busbar (500). As a result, the inter-busbar (500) can be protected from flames, etc.

[0050] Referring to FIG. 3, the shape of the heat-resistant cover (300) can be formed along the space between the battery modules (200). That is, a pair of side portions (310) facing each side of the facing battery modules (200) are formed, and a bottom portion (320) connecting the lower ends of the pair of side portions (310) is included. The pair of side portions (310) and the bottom portion (320) can be connected to form a U-shaped space when viewed from the side. Since the U-shaped space is formed long along the y-axis direction as illustrated in the drawing, bus bars for various electrical connections can be arranged by utilizing the space, as described below.

[0051] On the upper portions of a pair of side portions (310), wing portions (330) are formed, each extending toward the battery module (200). The wing portions (330) can be combined with the upper portion of the battery module (200) while covering the battery module (200). To this end, as illustrated in FIGS. 3 and 5, a plurality of snap holes (331) are formed in the wing portions (330). The snap holes (331) can be communicated with holes (not illustrated) formed in the upper portion of the battery module (200), and at this time, the holes formed in the upper portion of the battery module (200) can be formed, for example, in the upper portion of the end plate of the battery module (200) and can be communicated with the snap holes (331). A snap pin (400) can be inserted into the snap holes (331) to form a snap-fit ​​connection. As a result, the heat-resistant cover (300) can be fixed to the battery module (200) in a simple manner without bolt connection or the like.

[0052] A plurality of connector holes (311) may be formed in the side surface (310) of the heat-resistant cover (300). Connectors connected to each battery module (200) may be inserted through the connector holes (311). At this time, as illustrated in FIGS. 5 and 6, the connector holes (311) may be arranged so as not to face each other but to be offset from each other in a pair of facing side surfaces (310). Through this arrangement, even if a thermal runaway occurs in one of the facing battery modules (200) and a flame or the like is emitted through the connector hole (311), the flame or the like may be prevented from flowing into the connector hole (311) of the facing battery module (200), as indicated by the arrow (F) in FIG. 6.

[0053] Thus, according to one embodiment of the present invention, by not using a conventional heavy bulkhead structure and only using a heat-resistant cover having heat resistance at the bulkhead location, the weight and cost of the battery pack can be reduced, the assembly process can also be simplified, and parts of the battery module such as the inter-bus bar can be effectively protected from flames, etc.

[0054] Next, with reference to FIGS. 7 to 10, the configuration of a battery pack according to another embodiment of the present invention will be described.

[0055] FIG. 7 is a drawing illustrating a battery pack according to another embodiment of the present invention. FIG. 8 is a drawing illustrating a state in which the upper cover is removed from FIG. 7. FIG. 9 is an enlarged drawing illustrating part B of FIG. 7. FIG. 10 is a drawing illustrating a state in which the heat-resistant cover and upper cover of FIG. 7 are disassembled.

[0056] As shown in FIGS. 7 and 8, a battery pack according to another embodiment of the present invention further includes a plurality of connection boxes (600) arranged on the upper portions of some of the plurality of battery modules (200), a long bus bar (700) electrically connecting them, and an upper cover (350) covering the upper portions of the long bus bars (700).

[0057] A plurality of junction boxes (600) are responsible for the electrical connection and protection of the battery pack (10'). Its main functions may include collectively managing the electrical connection between the battery cells and external devices, protecting against overcurrent and overcharge, monitoring temperature, connecting to a battery management system (BMS), providing connector and connection functions, regulating and stabilizing voltage, and providing environmental protection. Through this, the plurality of junction boxes (600) can maintain the safety and efficiency within the battery pack (10'), prevent damage to the equipment, and support a stable power supply. The junction boxes (600) include various parts and various electrical connections within the battery pack (10'), and in particular, as illustrated in FIGS. 7 and 8, can be connected to a long bus bar (700) when a long-distance electrical connection is required within the battery pack (10').

[0058] In another embodiment of the present invention, the long bus bar (700) may be placed within a connection space (301) formed by the heat-resistant cover (300), as illustrated in FIG. 8. That is, the long bus bar (700) may be connected so as to cross the space formed by a pair of side portions (310) and a bottom portion (320) of the heat-resistant cover (300). Accordingly, a space for forming the long bus bar (700) can be secured with the configuration of the heat-resistant cover (300) acting as a partition wall without additional provision of a separate insulating structure, thereby increasing space efficiency and reducing manufacturing costs.

[0059] In addition, an upper cover (350) may be formed on the upper portion of the heat-resistant cover (300), that is, on the upper portion of the connecting space (301) between a pair of side portions (310) of the heat-resistant cover (300). The upper cover (350) may be formed of a heat-resistant material. As illustrated in FIG. 10, an insertion hole (351) into which a long bus bar (700) is inserted and a plurality of coupling holes (352) coupled with the heat-resistant cover (300) may be formed on the upper portion of the heat-resistant cover (300). A plurality of coupling hooks (332) for coupling with the coupling holes (352) are formed on the upper portion of the heat-resistant cover (300), specifically, on the corner portion where the side portions (310) and the wing portions (330) meet. The upper cover (350) may be fixed to the heat-resistant cover (300) by coupling the coupling hooks (332) and the coupling holes (352). In addition, since the upper cover (350) is fastened with a simple joint structure, the upper cover (350) can be easily removed when the internal configuration needs to be changed as needed. In addition, by enabling simple removal using this assembly method, not only is the assembly ease improved, but the protection of the long bus bar (700) can be achieved at low cost.

[0060] In particular, by providing the upper cover (350), when a flame occurs, it is possible to prevent high-temperature particles from falling onto the long bus bar (700) and causing damage. In particular, high-temperature gas generated during thermal runaway flows to a place with low resistance, and since the central part of the battery pack (10') where the heat-resistant cover (300) is structurally arranged has a lot of space and thus low resistance, the possibility of high-temperature conductors (particles) entering may increase. However, in the present embodiment, since the part is covered by the upper cover (350), damage caused by high-temperature particles can be prevented.

[0061] In addition, referring to FIG. 10, the heat-resistant cover (300) may further include a plurality of ring portions (312) arranged adjacent to the connector hole (311). These ring portions (312) may have a shape that protrudes from the inside of the heat-resistant cover (300) toward the opposite side portion (310) and is bent upward at the end. The ring portions (312) may support wires that are connected and extended from the battery module (200) and are pulled out through the connector hole (311). Through this, even if multiple wires are pulled out, they can be stably supported and organized, and thus damage and short circuits of the wires can be prevented.

[0062] In this way, according to another embodiment of the present invention, when connecting a long busbar across a battery pack, an insulating space can be secured with a simple structure by utilizing the space provided by the heat-resistant cover without a separate insulating member, thereby achieving the effects of improved safety and cost reduction. Furthermore, by further including an upper cover covering the space through which the long busbar passes, the long busbar can be prevented from being damaged by high-temperature particles when a thermal event occurs.

[0063] Meanwhile, the battery pack according to the present embodiment may have a structure in which a battery management system (BMS) that manages the temperature and voltage of the battery pack and a cooling device are added.

[0064] The above battery pack can be applied to various devices. These devices include electric bicycles, electric vehicles, hybrid vehicles, and other transportation vehicles. However, the present invention is not limited thereto and can be applied to various devices that utilize battery modules, which also fall within the scope of the present invention.

[0065] Although the preferred embodiments of the present invention have been illustrated and described above, the present invention is not limited to the specific embodiments described above, and various modifications may be made by those skilled in the art without departing from the spirit or scope of the present invention as claimed in the claims. Furthermore, such modifications should not be understood individually from the technical idea or prospect of the present invention.

[0066] [Explanation of symbols]

[0067] 10, 10' battery pack

[0068] 100 Pack Frames

[0069] 200 battery modules

[0070] 300 heat resistant cover

[0071] 310 side

[0072] 320 floor

[0073] 330 wing section

[0074] 350 top cover

[0075] 400 snap pins

[0076] 500 Inter Busbar

[0077] 600 connection box

[0078] 700 long busbar

Claims

1. Multiple battery modules, A pack frame accommodating the plurality of battery modules, A plurality of inter-busbars electrically connecting terminals of neighboring battery modules among the plurality of battery modules, and A battery pack comprising a heat-resistant cover arranged across the plurality of battery modules and covering the plurality of inter-bus bars.

2. In paragraph 1, The above heat-resistant cover is a battery pack including heat-resistant plastic.

3. In paragraph 1, The above plurality of battery modules are arranged in the row and column directions, and the battery modules arranged in the row direction are arranged such that the terminals included in each of the battery modules face each other. A battery pack in which the heat-resistant cover is arranged to extend in the heat direction across the terminals.

4. In paragraph 3, A battery pack in which the heat-resistant cover comprises a pair of side portions covering one side of the plurality of battery modules, a bottom portion connecting the lower portions of the pair of side portions, and a wing portion extending from the upper portion of each of the pair of side portions to cover a portion of the upper portion of the plurality of battery modules.

5. In paragraph 4, A battery pack in which each of the plurality of battery modules and the heat-resistant cover are fixed to each other through a snap-fit ​​connection at the wing portion.

6. In paragraph 5, The above wing portion includes a plurality of snap holes forming the snap-fit ​​joint, A battery pack further comprising a plurality of snap pins inserted into the above snap holes.

7. In paragraph 4, A plurality of connector holes are formed on each of the above pair of side surfaces to expose the connector terminals of each of the plurality of battery modules, A battery pack in which the plurality of connector holes on the above pair of side surfaces are arranged so as not to face each other.

8. In paragraph 4, A battery pack further comprising a long busbar disposed in a space between the pair of side portions.

9. In paragraph 8, A battery pack further comprising an upper cover covering a space between the pair of side portions of the heat-resistant cover.

10. In paragraph 9, The upper cover includes a plurality of joining holes, The above heat-resistant cover includes a battery pack having a plurality of coupling hooks that are coupled with the plurality of coupling holes at the corners where the side portion and the wing portion meet.

11. In paragraph 8, Further comprising a plurality of connection boxes arranged on top of some of the plurality of battery modules, The above long bus bar is a battery pack that electrically connects the connection box and the plurality of battery modules, or the plurality of connection boxes, to each other.

12. In paragraph 7, A battery pack wherein the heat-resistant cover further includes a plurality of ring portions arranged adjacent to each of the connector holes.

13. A device comprising at least one battery pack according to paragraph 1.

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