Device including battery pack

Abstract

The device according to the present invention comprises: a battery pack comprising a lower frame in which a battery module is accommodated and an upper cover covering the lower frame; a device housing located on the battery pack; and a smoke control boundary wall disposed between the battery pack and the device housing.

Description

Device including a battery pack

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

[0002] This application claims the benefit of priority to Korean Patent Application No. 10-2023-0181725, filed December 14, 2023, the entire contents of which are incorporated herein by reference.

[0003] The present invention relates to a device including a battery pack, and more particularly, to a device including a battery pack capable of suppressing thermal runaway.

[0004] To address air pollution caused by conventional gasoline-powered vehicles, which use fossil fuels, development of rechargeable secondary batteries continues. Secondary batteries are attracting significant attention not only as an energy source for mobile devices like cell phones, digital cameras, laptops, and wearables, but also as a power source for electric bicycles, electric cars, hybrid electric vehicles, and plug-in hybrid electric vehicles.

[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 coated with positive and negative electrode active materials, respectively, and a negative electrode plate disposed with a separator between them, and a battery case that seals and houses the electrode assembly together with an electrolyte.

[0007] Secondary batteries used in small devices are configured with two to three battery cells, but secondary batteries used in medium to large devices such as automobiles utilize battery modules in which multiple battery cells are electrically connected. These battery modules enhance capacity and output by forming a battery cell stack by connecting multiple battery cells in series or parallel. In addition, one or more battery modules may be mounted together with various control and protection systems, such as a Battery Disconnect Unit (BDU), a Battery Management System (BMS), and a cooling system, to form a battery pack.

[0008] In general, if the temperature of a secondary battery exceeds the appropriate temperature, the performance of the secondary battery may deteriorate, and in severe cases, there is a risk of explosion or fire. In particular, in a battery module or battery pack equipped with a large number of secondary batteries, i.e., battery cells, the heat from the numerous battery cells is accumulated in a small space, which can cause the temperature to rise more quickly and severely. In other words, a battery module with a large number of battery cells stacked on top of each other and a battery pack equipped with such battery modules can achieve high output, but it is not easy to remove the heat generated from the battery cells during charging and discharging. If the heat dissipation of the battery cells is not properly performed, the deterioration of the battery cells will be accelerated, shortening their lifespan. If a thermal runaway phenomenon occurs, there is a high possibility of explosion or fire.

[0009] Figure 1 illustrates a conventional device including a battery pack.

[0010] Figure 2 is a schematic illustration of how external ignition occurs when a battery pack catches fire in a conventional device.

[0011] Referring to FIGS. 1 and 2 together, a conventional device (1) may be, for example, an electric vehicle including a battery pack (10). Inside the device (1), a predetermined gap (11) may exist between the device housing (20) and the battery pack (10). When an internal fire occurs in the battery pack (10), the battery pack (10) discharges a venting gas (30) containing a flammable substance to the outside. At this time, if the discharged venting gas (30) enters the gap (11) due to the influence of wind or the like, there may be a problem in that it meets the high-temperature surface (HP) of the battery pack (10) and causes an external ignition.

[0012] In order to solve the above problem, the present invention aims to prevent ignition from the outside of the battery pack by blocking venting gas discharged to the outside when the battery pack ignites from flowing back into the battery pack.

[0013] The device of the present invention comprises a battery pack including a lower frame in which a battery module is accommodated and an upper cover covering the lower frame; a device housing positioned on the battery pack; and a smoke barrier disposed between the battery pack and the device housing.

[0014] In one embodiment, the battery pack includes a venting hole for discharging venting gas to the outside, and the smoke exhaust boundary wall is positioned adjacent to the venting hole to block the venting gas from flowing into the upper cover.

[0015] In one embodiment, the venting hole may be formed in a side surface of the lower frame.

[0016] In one embodiment, the smoke barrier may block more than half of the gap between the battery pack and the device housing.

[0017] In one embodiment, the smoke barrier wall may have a fixed shape regardless of temperature.

[0018] In one embodiment, on a planar surface, the smoke barrier wall may be disposed along at least a portion of the perimeter of the upper cover.

[0019] In one embodiment, the smoke barrier wall may be in contact with the upper cover.

[0020] In one embodiment, the smoke barrier may change shape or volume depending on temperature.

[0021] In one embodiment, the smoke barrier may be a refractory expansion tube that expands in volume as the upper cover is heated to close the gap between the battery pack and the device housing.

[0022] In one embodiment, the smoke barrier may include a shape memory alloy and may change shape as the upper cover is heated to close the gap between the battery pack and the device housing.

[0023] In one embodiment, the smoke barrier may be in contact with the device housing.

[0024] In one embodiment, the smoke barrier wall may be in contact with the upper cover and the device housing.

[0025] The device of the present invention includes a smoke barrier disposed between the device housing and the battery pack, thereby preventing venting gas discharged to the outside from meeting the high-temperature battery pack and causing external ignition.

[0026] Figure 1 illustrates a conventional device including a battery pack.

[0027] Figure 2 is a schematic illustration of how external ignition occurs when a battery pack catches fire in a conventional device.

[0028] Figure 3 illustrates a battery pack of one embodiment.

[0029] Figure 4 partially illustrates the interior of a battery pack of one embodiment.

[0030] Figure 5 illustrates a battery module of one embodiment.

[0031] Figure 6 illustrates a device including a smoke barrier of one embodiment.

[0032] Figure 7 illustrates a device including a smoke barrier of one embodiment.

[0033] Figure 8 illustrates a device including a smoke barrier of one embodiment.

[0034] Figure 9 illustrates a device including a smoke barrier of one embodiment.

[0035] Figure 10 illustrates a device including a smoke barrier of one embodiment.

[0036] Figure 11 illustrates a device including a smoke barrier of one embodiment.

[0037] Figure 12 illustrates a device including the smoke barrier of Figure 11.

[0038] Figure 13 illustrates a device including a smoke barrier of one embodiment.

[0039] Figure 14 illustrates a device including the smoke boundary wall of Figure 13.

[0040] Figure 15 illustrates a device including a smoke barrier of one embodiment.

[0041] Hereinafter, various embodiments of the present invention will be described in detail with reference to the attached drawings so that those skilled in the art can easily implement the invention. The present invention may be implemented in various different forms and is not limited to the embodiments described herein.

[0042] In order to clearly explain the present invention, parts that are not related to the description are omitted, and the same reference numerals are used for identical or similar components throughout the specification.

[0043] Furthermore, the sizes and thicknesses of each component shown in the drawings are arbitrarily indicated for convenience of explanation, and thus the present invention is not necessarily limited to the illustrated components. In the drawings, the thicknesses are enlarged to clearly represent various layers and regions. Furthermore, in the drawings, the thicknesses of some layers and regions are exaggerated for convenience of explanation.

[0044] Furthermore, when we say that a layer, membrane, region, plate, or other part is "on" or "over" another part, this includes not only cases where it is "directly on" the other part, but also cases where there are other parts in between. When we say that a part is "directly on" another part, we mean that there are no other parts in between. Furthermore, when we say that a part is "on" or "over" a reference part, we mean that it is located above or below the reference part, and we do not necessarily mean that it is located "above" or "over" the reference part in the opposite direction of gravity.

[0045] Additionally, throughout the specification, whenever a part is said to “include” a component, this does not mean that it excludes other components, but rather that it may include other components, unless otherwise specifically stated.

[0046] Also, throughout the specification, when we say "on a flat surface," we mean when the target portion is viewed from above.

[0047] 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.

[0048] The device of the present invention will be described with reference to FIGS. 3 to 15 below.

[0049] The device of the present invention,

[0050] A battery pack comprising a lower frame in which a battery module is stored and an upper cover covering the lower frame;

[0051] a device housing positioned on the battery pack; and

[0052] A smoke barrier wall disposed between the battery pack and the device housing is included.

[0053]

[0054] Figure 3 illustrates a battery pack of one embodiment.

[0055] Figure 4 partially illustrates the interior of a battery pack of one embodiment.

[0056] Referring to FIGS. 3 and 4 together, a battery pack (1000) according to one embodiment of the present invention may include at least one battery module (1300) and a pack frame (1100) that accommodates the battery module (1300). The pack frame (1100) may include a lower frame (1110) and an upper cover (1120) that covers the lower frame (1110), and a plurality of battery modules (1300) may be positioned on the bottom of the lower frame (1110). That is, a plurality of battery modules (1300) are arranged within the lower frame (1110), and the lower frame (1110) and the plurality of battery modules (1300) may be covered by the upper cover (1120).

[0057] Meanwhile, the battery pack (1000) according to the present embodiment may further include a venting hole (1200) formed in the pack frame (1100). Specifically, the venting hole (1200) may be formed on a side surface of the lower frame (1110). By forming the venting hole (1200), the venting gas generated inside the battery pack (1000) can be effectively discharged to the outside of the battery pack (1000).

[0058] One or more venting holes (1200) may be formed, for example, one may be formed. However, the number of venting holes (1200) is not limited thereto, and two or more may be formed as needed. Hereinafter, as an example, it will be described that one venting hole (1200) is formed on the side of the lower frame (1110).

[0059] Figure 5 illustrates a battery module of one embodiment.

[0060] Referring to FIG. 5, a battery module (1300) may include a battery cell stack (1320) formed by stacking a plurality of battery cells (1310) along a preset direction, and a module frame (1330) that accommodates the battery cell stack (1320). The module frame (1330) may have a structure that covers four sides corresponding to the upper and lower sides and the left and right sides of the battery cell stack (1320), and the front and back sides of the battery cell stack (1320) may have an open structure. The front and back sides of the battery cell stack (1320) opened by the module frame (1330) may be covered by an end plate (1340). Here, the plurality of battery cells (1310) may be pouch-type secondary batteries, but the embodiment is not limited thereto. For example, the battery cell (1310) may be of a jelly-roll type, a stack type, a stack-folding type (including a stack-Z-folding type), or a lamination-stack type in addition to a pouch type.

[0061]

[0062] Figure 6 illustrates a device including a smoke barrier of one embodiment.

[0063] Referring to FIG. 6, a device (100) of one embodiment includes a battery pack (1000) described above, a device housing (2000) disposed on the battery pack (1000), and a smoke barrier (3000) disposed between the battery pack (1000) and the device housing (2000).

[0064] The device housing (2000) is schematically illustrated, and its shape may be modified in various ways depending on the type of device (100). For example, if the device (100) is an electric vehicle, the device housing (2000) may be a vehicle chassis (Chassi). A gap (1111) of 10 mm to 30 mm may exist between the device housing (2000) and the upper cover (1120) of the battery pack (1000).

[0065] When an internal fire occurs in the battery pack (1000), the battery pack (1000) discharges venting gas (1300) toward the outside from the venting hole (1200) formed in the lower frame (1110). In general, in a situation where the battery pack (1000) ignites, the device (100) may be stopped, i.e., in a stationary state, and the venting gas (1300) discharged due to factors such as wind may flow back into the gap (1111), and there is a risk of ignition when it meets the high temperature surface (HP) of the upper cover (1120) of the battery pack (1000).

[0066] A smoke barrier (3000) is disposed between the battery pack (1000) and the device housing (2000). The present invention includes a smoke barrier (3000) disposed between the battery pack (1000) and the device housing (2000), thereby preventing the venting gas (1300) from being re-introduced into the gap (1111) between the battery pack (1000) and the device housing (2000). Accordingly, the venting gas (1300) discharged to the outside can be prevented from igniting externally in the battery pack (1000).

[0067] In order to effectively block the venting gas (1300) from flowing into the upper cover (1120) of the battery pack (1000), a smoke exhaust boundary wall (3000) may be positioned adjacent to the venting hole (1200). In addition, the smoke exhaust boundary wall (3000) may be positioned adjacent to the edge of the battery pack (1000) to prevent the venting gas (1300) from flowing into the inside of the battery pack (1000).

[0068] In one embodiment, the smoke barrier (3000) may be made of a heat-resistant material capable of absorbing heat when the battery pack (1000) is ignited. For example, the smoke barrier (3000) may be made of aluminum or steel. In addition, the height of the smoke barrier (3000) may be greater than half of the gap (1111), which is a straight-line distance between the battery pack (1000) and the device housing (2000).

[0069] In one embodiment, the smoke barrier wall (3000) may have a fixed position and fixed shape regardless of the temperature of the upper cover (1120).

[0070] The smoke barrier wall (3000) may be in contact with the device housing (2000) and may be formed specifically on the lower surface of the device housing (2000). For example, the smoke barrier wall (3000) may have a shape that protrudes from the lower surface of the device housing (2000) toward the battery pack (1000).

[0071] Additionally, the smoke barrier wall (3000) may have a bar shape.

[0072] However, the shape of the smoke barrier (3000) is not limited to this.

[0073] In the following description, the differences from the device (100) of FIG. 6 will be explained, and in other parts, the above-mentioned contents are equally applied and a detailed description will be omitted.

[0074] Figure 7 illustrates a device including a smoke barrier of one embodiment.

[0075] In one embodiment of the device (100-1), the smoke barrier wall (3000-1) may be in contact with the device housing (2000) and formed on the lower surface of the device housing (2000).

[0076] The smoke exhaust boundary wall (3000-1) may include a portion that extends inward compared to the smoke exhaust boundary wall (3000) of FIG. 6. Accordingly, the fixing force between the smoke exhaust boundary wall (3000-1) and the device housing (2000) may be further secured.

[0077] Figure 8 illustrates a device including a smoke barrier of one embodiment.

[0078] The device (100-a) of one embodiment may include a smoke barrier wall (3000-a) that contacts the upper cover (1120) of the battery pack (1000). Specifically, the smoke barrier wall (3000-a) may be formed on the upper surface of the upper cover (1120).

[0079] For example, the smoke boundary wall (3000-a) may have a shape that protrudes from the upper surface of the upper cover (1120) toward the device housing (2000).

[0080] Figure 9 illustrates a device including a smoke barrier of one embodiment.

[0081] In one embodiment of the device (100-a-1), the smoke barrier wall (3000-a-1) may be in contact with the battery pack (1000) and may be formed on the upper surface of the upper cover (1120) of the battery pack (1000).

[0082] The smoke exhaust boundary wall (3000-a-1) may include a portion that extends inwardly compared to the smoke exhaust boundary wall (3000-a) of FIG. 8. Accordingly, the fixing force between the smoke exhaust boundary wall (3000-a-1) and the battery pack (2000) may be further secured. FIG. 10 illustrates a device including a smoke exhaust boundary wall according to one embodiment.

[0083] As illustrated in FIG. 10, the device (100-b) of one embodiment may include a smoke barrier (3000-b) that contacts both the upper cover (1120) of the battery pack (1000) and the device housing (2000). That is, the smoke barrier (3000-b) may completely block the gap (1111) between the battery pack (1000) and the device housing (2000).

[0084]

[0085] In another embodiment of the device of the present invention, the smoke barrier wall may be operable depending on temperature. For example, the smoke barrier wall may change shape or volume depending on temperature.

[0086] Figure 11 illustrates a device including a smoke barrier of one embodiment.

[0087] Figure 12 illustrates a device including the smoke barrier of Figure 11.

[0088] Referring to FIGS. 11 and 12, the device (100-c) of one embodiment may include a smoke boundary wall (3100) whose volume expands with temperature.

[0089] For example, the smoke boundary wall (3100) may be an expansion tube that expands in volume above a certain temperature. Specifically, the smoke boundary wall (3100) may be formed of a material such as rubber or aluminum foil, which expands in volume due to gas generated inside the wall above a certain temperature. Alternatively, the smoke boundary wall (3100) may be formed of a material such as foamed silicone, which itself has foaming properties. The smoke boundary wall (3100) expands at a temperature of about 100°C or higher, and can withstand temperatures of about 400°C to 500°C or higher.

[0090] In one embodiment, the smoke barrier wall (3100) may be disposed on the upper cover (1120) of the battery pack (1000) and may contact the upper surface of the upper cover (1120). When the temperature of the surface (HP) of the upper cover (1120) is less than about 120°C, the smoke barrier wall (3100) may hardly block the gap (1111) as illustrated in FIG. 11. However, when the temperature of the surface (HP) of the upper cover (1120) is 120°C or higher due to internal ignition of the battery pack (1000), the smoke barrier wall (3100) may expand and have a shape that completely blocks the gap (1111).

[0091] Accordingly, the venting gas (1300) discharged to the outside from the venting hole (1200) does not flow into the gap (1111) between the battery pack (1000) and the device housing (2000), and external ignition of the battery pack (1000) can be prevented.

[0092] Figure 13 illustrates a device including a smoke barrier of one embodiment.

[0093] Figure 14 illustrates a device including the smoke boundary wall of Figure 13.

[0094] Referring to FIGS. 13 and 14, the device (100-d) of one embodiment may include a smoke boundary wall (3200) whose shape changes depending on temperature. For example, the smoke boundary wall (3200) may be a shape memory alloy.

[0095] In one embodiment, the smoke barrier wall (3200) may be disposed on the upper cover (1120) of the battery pack (1000) and may contact the upper surface of the upper cover (1120). When the temperature of the surface (HP) of the upper cover (1120) is less than 120°C, the smoke barrier wall (3200) may hardly block the gap (1111) as illustrated in FIG. 13. However, when the temperature of the surface (HP) of the upper cover (1120) is 120°C or higher due to internal ignition of the battery pack (1000), the smoke barrier wall (3200) may expand and have a shape that completely blocks the gap (1111).

[0096] Accordingly, the venting gas (1300) discharged to the outside from the venting hole (1200) does not flow into the gap (1111) between the battery pack (1000) and the device housing (2000), and external ignition of the battery pack (1000) can be prevented.

[0097]

[0098] Meanwhile, the smoke barrier wall (3000-c) may be arranged along at least a portion of the perimeter of the upper cover (1120) on a plane.

[0099] FIG. 15 illustrates a device including a smoke barrier wall of one embodiment. Referring to FIG. 15, the smoke barrier wall (3000-c) may be positioned along at least a portion of the perimeter of the upper cover (1120) of the battery pack (1000).

[0100] Referring to FIG. 15, the smoke exhaust boundary wall (3000-c) may include a first side (sb1) adjacent to the venting hole (1200), and a first smoke exhaust boundary wall (3000-c1) disposed along a second side (sb2) and a third side (sb3) adjacent to the first side (sb1).

[0101] Additionally, the smoke exhaust boundary wall (3000-c) can improve the smoke exhaust effect by including a second smoke exhaust boundary wall (3000-c2) facing the first smoke exhaust boundary wall (3000-c1).

[0102] However, the embodiment is not limited thereto, and the smoke exhaust boundary wall (3000-c) may include only the first smoke exhaust boundary wall (3000-c1) that is relatively closer to the venting hole (1200), and the second smoke exhaust boundary wall (3000-c2) may be omitted.

[0103] Additionally, the first smoke boundary wall (3000-c1) may be placed only on the first side (sb1) relatively adjacent to the venting hole (1200), and may not be placed on the second side (sb2) and the third side (sb3).

[0104] That is, the smoke boundary wall (3000-c) is essentially placed on the first side (sb1) adjacent to the venting hole (1200), and may be additionally placed along the perimeter of the upper cover (1120) as needed.

[0105] This can be equally applied to the smoke exhaust boundary walls (3000-a, 3000-a-1, 3000-b, 3100, 3200) described above in FIGS. 8 to 14. As in FIGS. 6 and 7, in the case of the smoke exhaust boundary walls (3000, 3000-1) protruding from the device housing (2000), it can be applied so as to be arranged adjacent to at least a portion of the perimeter of the upper cover (1120) on a plane.

[0106]

[0107] Although the preferred embodiments of the present invention have been described in detail above, the scope 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 fall within the scope of the present invention.

[0108] [Explanation of symbols]

[0109] 100: Device

[0110] 1000: Battery Pack

[0111] 1100: Pack Frame

[0112] 1110: Lower frame

[0113] 1120: Top cover

[0114] 1200: Venting Hall

[0115] 1300: Battery module

[0116] 2000: Device Housing

[0117] 3000: Smoke barrier

Claims

1. A battery pack including a lower frame in which a battery module is stored and an upper cover covering the lower frame; a device housing positioned on the battery pack; and A device comprising a smoke barrier disposed between the battery pack and the device housing.

2. In paragraph 1, The above battery pack includes a venting hole for discharging venting gas to the outside, A device wherein the above-mentioned smoke barrier is positioned adjacent to the venting hole to block the venting gas from flowing into the upper cover.

3. In paragraph 2, The above venting hole is a device formed on the side of the lower frame.

4. In paragraph 2, The above smoke barrier is a device that blocks more than half of the gap between the battery pack and the device housing.

5. In paragraph 1, A device wherein the above smoke barrier has a fixed shape regardless of temperature.

6. In paragraph 1, In a planar view, the smoke barrier is a device arranged along at least a portion of the perimeter of the upper cover.

7. In paragraph 1, A device wherein the above smoke barrier wall is in contact with the upper cover.

8. In paragraph 1, The above smoke barrier is a device whose shape or volume changes depending on the temperature.

9. In paragraph 8, A device wherein the above-mentioned smoke barrier is a refractory expansion tube, and expands in volume according to the temperature of the upper cover to close the gap between the battery pack and the device housing.

10. In paragraph 8, A device wherein the above-described smoke barrier comprises a shape memory alloy and changes shape according to an increase in temperature of the upper cover to close a gap between the battery pack and the device housing.

11. In paragraph 1, A device wherein the above smoke barrier is in contact with the device housing.

12. In paragraph 1, A device wherein the above smoke barrier is in contact with the upper cover and the device housing.

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