Partition member with fire extinguishing pad and pack case including same

Abstract

The disclosed invention relates to a partition member installed between multiple battery modules mounted in a battery pack, and in one example, at least one side of the partition member has a plurality of regularly aligned groove structures, and fire extinguishing pads containing a fire extinguishing agent are installed within the plurality of groove structures.

Description

[Technical Field]

[0001] The present invention relates to a lightweight partition member equipped with a fire extinguishing pad that automatically discharges a fire extinguishing agent in response to a fire that breaks out inside the pack case, and to a pack case including the same.

[0002] This application claims the benefit of Korean Application No. 10-2023-0029893, filed on March 7, 2023, which is incorporated herein by reference in its entirety. [Background technology]

[0003] Unlike primary batteries, secondary batteries are rechargeable and have the potential to be small and have large capacities, and as such, they have been the subject of much research and development in recent years. Demand for secondary batteries as an energy source is rapidly increasing due to the increasing technological development and demand for mobile devices, as well as the emergence of electric vehicles and energy storage systems in response to modern demands for environmental protection.

[0004] Secondary batteries are classified into coin-type batteries, cylindrical batteries, prismatic batteries, and pouch-type batteries depending on the shape of the battery case. The electrode assembly installed inside the battery case of a secondary battery is a power generating element that can be charged and discharged and is made up of a laminated structure of electrodes and a separator.

[0005] Since secondary batteries are required to be used continuously for a long period of time, it is necessary to effectively control the heat generated during the charging and discharging process.If secondary batteries are not cooled smoothly, a positive feedback chain reaction will occur in which a rise in temperature causes an increase in current, and the increase in current causes another rise in temperature, resulting in a catastrophic state of thermal runaway.

[0006] Furthermore, when secondary batteries are grouped together in the form of a module or pack, thermal runaway in one secondary battery can cause other surrounding secondary batteries to continuously overheat, resulting in a thermal propagation phenomenon. That is, when thermal runaway occurs in a battery module within a battery pack, a large amount of conductive dust, gas, and flames are emitted from the high-voltage terminal of the battery module, causing dust to accumulate at the high-voltage terminals of other adjacent battery modules, and the heat transfer caused by the gas and flames triggers a thermal propagation phenomenon.

[0007] Designs that prevent or delay the heat transfer of high heat and / or flames from a battery cell or module that has experienced thermal runaway to adjacent battery cells or modules include insulation designs that use insulating materials to prevent or delay heat transfer from a battery module that has experienced thermal runaway to an adjacent battery module, heat dissipation designs that quickly release heat from a battery module that has experienced thermal runaway to the outside of the battery pack in an early stage to reduce heat transfer to adjacent battery modules, and fire extinguishing designs that discharge fire extinguishing agents when thermal runaway occurs to actively suppress the spread of fire.

[0008] The prevention and delay of heat propagation is particularly important in electric vehicles, which can lead to fatal accidents, and related regulations are being strengthened daily. Specifically, a sufficient delay time is required for the heat propagation phenomenon to dissipate, ensuring time for emergency evacuation and safety measures to be taken after a thermal runaway occurs. However, when various designs to prevent heat propagation are applied, the space utilization rate of the pack case is reduced, the capacity per unit volume of the battery pack is reduced, and battery pack designs must be changed. Therefore, an effective solution that takes these issues into consideration is needed. Summary of the Invention [Problem to be solved by the invention]

[0009] An object of the present invention is to provide a partition member that can prevent, suppress, or delay heat propagation in a battery pack.

[0010] However, the technical problems that the present invention aims to solve are not limited to the above-mentioned problems, 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]

[0011] The present invention relates to a partition member installed between multiple battery modules mounted in a battery pack, and in one example, at least one side of the partition member has a plurality of regularly aligned groove structures, and fire extinguishing pads containing a fire extinguishing agent are installed within the plurality of groove structures.

[0012] In one embodiment of the present invention, the fire-extinguishing pad may include a porous pad, a plurality of capsules contained within the pad, and a liquid fire-extinguishing agent sealed within the capsules.

[0013] For example, the liquid fire extinguishing agent may be a fluorinated ketone.

[0014] When the temperature of the fire-extinguishing pad is in the temperature range of 120 to 220°C, the capsules can melt or burst due to internal vapor pressure to release the fire-extinguishing agent.

[0015] The extinguishing agent released from the capsule can be released to the outside through the pores of the porous pad.

[0016] In one embodiment of the present invention, the plurality of groove structures may form a honeycomb structure in which a plurality of hexagonal grooves are regularly aligned.

[0017] Here, the honeycomb structure may be provided on both side surfaces of the partition member.

[0018] The honeycomb structures provided on both sides of the partition member may be arranged alternately at half pitches in the vertical and / or horizontal directions without communicating with each other.

[0019] Meanwhile, the present invention can provide a pack case including a base plate, side plates surrounding the outer periphery of the base plate, partition members of the above configuration arranged vertically and / or horizontally to partition a storage space limited by the side plates, and a lid that closes the top surface of the storage space.

[0020] In one example, the partition member may be a cross beam. [Effects of the Invention]

[0021] According to the partition member of the present invention having the above-described configuration, the fire-extinguishing pad exposed on one side thereof discharges the built-in fire-extinguishing agent in response to the abnormally high temperature of the battery module that has experienced thermal runaway. The discharge of the fire-extinguishing agent cools or extinguishes the high-temperature gases, particles, and flames caused by the thermal runaway, thereby thermally protecting other surrounding battery modules and suppressing or delaying heat propagation.

[0022] Furthermore, the partition member of the present invention is configured to incorporate a fire extinguishing pad containing a fire extinguishing agent, thereby eliminating the need for a separate space and device in the pack case for storing and discharging the fire extinguishing agent. Therefore, by applying the partition member of the present invention, it is possible to effectively address the heat propagation problem without changing the overall design of the pack case and without sacrificing the capacity of the battery pack.

[0023] Furthermore, the partition member of the present invention has a honeycomb structure for the space that houses the fire-extinguishing pad, thereby ensuring sufficient rigidity and achieving a lighter weight, which contributes to a reduction in the weight of the pack case.

[0024] However, the technical effects that can be obtained by the present invention are not limited to the effects described above, and other effects not mentioned can be clearly understood by those skilled in the art from the description of the invention described below.

[0025] The following drawings attached to this specification illustrate preferred embodiments of the present invention and, together with the detailed description of the invention described below, serve to further understand the technical concept of the present invention, and therefore the present invention should not be interpreted as being limited solely to the matters depicted in such drawings. [Brief explanation of the drawings]

[0026] [Figure 1] 1 is a view showing an example of installation of a partition member according to an embodiment of the present invention; [Figure 2] 2 is a cross-sectional view of the partition member of FIG. 1 taken along line "AA." [Figure 3] 1 is a cross-sectional view of a fire extinguishing pad. [Figure 4] 10 is a view showing another embodiment of the partition member. [Figure 5] 1 is a view showing an embodiment in which a fire extinguishing pad is attached to a partition member. [Figure 6] 10 is a view showing another embodiment in which a fire extinguishing pad is attached to a partition member. [Figure 7] 1 is a view showing a pack case including a partition member according to an embodiment of the present invention; [Figure 8] 8 is a view showing an embodiment of a battery pack in which a battery module is mounted in the pack case of FIG. 7; [Figure 9] 8 is a view showing another embodiment of a battery pack in which a battery module is mounted in the pack case of FIG. 7; DETAILED DESCRIPTION OF THE INVENTION

[0027] Because the present invention is susceptible to various modifications and can have various embodiments, specific embodiments will be described in detail below.

[0028] However, this is not intended to limit the invention to any particular embodiment, but rather to be understood as including all modifications, equivalents, or alternatives falling within the spirit and scope of the invention.

[0029] In the present invention, terms such as "comprise" and "have" are intended to specify the presence of features, numbers, steps, operations, components, parts or combinations thereof described in the specification, and may be understood as not precluding the presence or additional possibility of one or more other features, numbers, steps, operations, components, parts or combinations thereof.

[0030] Furthermore, in the present invention, when a layer, film, region, plate, or other portion is described as being "on" another portion, this includes not only the case where it is "directly on" the other portion, but also the case where there is another portion therebetween. Conversely, when a layer, film, region, plate, or other portion is described as being "under" the other portion, this includes not only the case where it is "directly under" the other portion, but also the case where there is another portion therebetween. Furthermore, in this application, being "located on" can include not only the case where it is located at the top, but also the case where it is located at the bottom.

[0031] The present invention relates to a partition member installed between multiple battery modules mounted in a battery pack, and in one example, at least one side of the partition member has a plurality of regularly aligned groove structures, and fire extinguishing pads containing a fire extinguishing agent are installed within the plurality of groove structures.

[0032] In one embodiment of the present invention, the fire-extinguishing pad may include a porous pad, a plurality of capsules contained within the pad, and a liquid fire-extinguishing agent sealed within the capsules.

[0033] According to the partition member of the present invention having the above-described configuration, the fire-extinguishing pad exposed on one side thereof discharges the built-in fire-extinguishing agent in response to the abnormally high temperature of the battery module that has experienced thermal runaway. The discharge of the fire-extinguishing agent cools or extinguishes the high-temperature gases, particles, and flames caused by the thermal runaway, thereby thermally protecting other surrounding battery modules and suppressing or delaying heat propagation.

[0034] Furthermore, the partition member of the present invention is configured to incorporate a fire extinguishing pad containing a fire extinguishing agent, thereby eliminating the need for a separate space and device in the pack case for storing and discharging the fire extinguishing agent. This means that by applying the partition member of the present invention, it is possible to effectively address the heat propagation problem without changing the overall design of the pack case or sacrificing the capacity of the battery pack.

[0035] Furthermore, the partition member of the present invention has a honeycomb structure for the space that houses the fire-extinguishing pad, thereby ensuring sufficient rigidity and achieving weight reduction, which contributes to a reduction in the weight of the pack case.

[0036] Hereinafter, specific embodiments of the partition member 130 for a pack case according to the present invention will be described in detail with reference to the accompanying drawings. For reference, the directions of front, back, up, down, left, and right used in the following description to specify relative positions are intended to aid in understanding the invention, and unless otherwise specified, are based on the directions shown in the drawings.

[0037] (First embodiment) FIG. 1 is a view showing an example of installation of a partition member 130 according to the present invention, and FIG. 2 is a cross-sectional view of the partition member 130 of FIG. 1 taken along line "AA."

[0038] 1 is a diagram showing that a partition member 130 (hereinafter simply referred to as "partition member") of a battery pack according to the present invention can be applied as a center beam 140 and / or cross beams 150 of a pack case 100. Here, the center beam 140 refers to a vertical partition member 130 that crosses the center of the pack case 100 and divides the internal storage space into left and right, and the cross beams 150 refer to horizontal partition members 130 that form a lattice shape relative to the center beam 140.

[0039] The partition member 130 of the present invention corresponds to a member that is installed between the plurality of battery modules 200 mounted in the battery pack 10 to form a plurality of storage spaces, and one battery module 200 is installed in each divided storage space. Therefore, the partition member 130 functions as a wall that separates or isolates the battery modules 200, and the partition member 130 is necessarily involved in heat transfer between the battery modules 200.

[0040] Fig. 2 is a cross-sectional view of one cross beam 150 separated from the pack case 100 of Fig. 1. For reference, Fig. 2 shows one example of the partition member 130, and the same structure as Fig. 2 can also be applied to the center beam 140. Referring to Fig. 2, the cross beam 150, which is the partition member 130, has a fire-extinguishing pad 170 exposed on one surface, and the fire-extinguishing pad 170 contains a fire-extinguishing agent 176.

[0041] The fire-extinguishing pad 170 exposed on one side of the cross beam 150 comes into contact with the battery modules 200 mounted in the accommodation spaces, a plurality of which are provided in the pack case 100 of FIG. 1. That is, the fire-extinguishing pad 170 transfers heat to the battery modules 200 mainly in the form of conductive heat transfer. If thermal runaway occurs in a battery cell 210 constituting the battery module 200 and the battery cell 210 becomes abnormally hot, the fire-extinguishing pad 170 provided on the partition member 130 receives an abnormally large amount of heat and discharges the built-in fire-extinguishing agent 176 in response to the heat. The discharge of the fire-extinguishing agent 176 cools or extinguishes high-temperature gases, particles, and flames caused by the thermal runaway, thereby thermally protecting other surrounding battery modules 200 and suppressing or delaying heat propagation.

[0042] The partition member 130 of the present invention is configured to incorporate a fire extinguishing pad 170 containing a fire extinguishing agent 176, thereby eliminating the need for the pack case 100 to have a separate space and device for containing and discharging the fire extinguishing agent 176. This means that by applying the partition member 130 of the present invention, it is possible to effectively address the heat propagation problem without changing the overall design of the pack case 100 or sacrificing the capacity of the battery pack 10.

[0043] 3 is a cross-sectional view of a fire-extinguishing pad 170 according to one embodiment. Referring to the drawing, the fire-extinguishing pad 170 includes a porous pad 172, a plurality of capsules 174 housed within the porous pad 172, and a liquid fire-extinguishing agent 176 sealed within the capsules 174. Sealing the liquid fire-extinguishing agent 176 within the capsules 174 allows the fire-extinguishing agent 176 to be stably stored within the fire-extinguishing pad 170 until a thermal runaway event occurs. The use of the liquid fire-extinguishing agent 176 in particular allows the liquid fire-extinguishing agent 176 to occupy a small space while still providing effective fire-extinguishing capabilities due to its explosive volume expansion upon vaporization. Furthermore, the porous pad 172, which serves as a type of container for the capsules 174, contains numerous pores, making it suitable for discharging the vaporized fire-extinguishing agent 176.

[0044] For example, a preferred liquid fire extinguishing agent 176 may be fluorinated ketone. Fluorinated ketone is a substance artificially created by substituting fluorine for hydrogen atoms in ketone. It is colorless, odorless, and has a viscosity similar to that of water, making it easy to store in capsule 174. The stable fluorine provides a dielectric strength more than twice that of nitrogen, making it non-conductive and non-reactive with materials it comes into contact with. Its extremely low surface tension allows it to spread easily without forming droplets upon contact with an object, making it highly suitable for fire extinguishing. Furthermore, fluorinated ketones are non-toxic and harmless to humans, while also extinguishing fires. They evaporate quickly upon contact with fire or smoke, making them an effective fire retardant that quickly absorbs heat. They leave no residue after evaporation, making them more environmentally friendly than existing fire extinguishing materials. In particular, the non-conductivity provided by the stable nature of fluorine makes them suitable for use in fighting fires in battery packs 10 caused by thermal runaway in secondary batteries.

[0045] However, because fluorinated ketones have a boiling point of 49°C, which is much lower than that of water, they exist in a liquid state at room temperature but quickly vaporize as the temperature rises. Therefore, the material and thickness of the capsules 174 containing the liquid fluorinated ketone and the porous pad 172 surrounding the capsules 174 must be designed so that they can adequately function as thermal insulators. For example, when the temperature of the fire-extinguishing pad 170 in contact with the battery module 200 is in the range of 120 to 220°C, the capsules 174 may be designed to melt or burst due to the vapor pressure of the fire-extinguishing agent 176 vaporized therein, thereby releasing the fire-extinguishing agent 176. The fire-extinguishing agent 176 released from the capsules 174 is released to the outside through the pores of the porous pad 172, thereby enabling early response to a fire occurring in the battery module 200.

[0046] 1, the partition member 130 has a plurality of regularly arranged groove structures 132 on its surface, and the fire extinguishing pad 170 is fixed in the groove structures 132. Here, the regular groove structure 132 shown in FIG. 1 has a honeycomb structure 134 in which a plurality of hexagonal grooves are regularly arranged. The honeycomb structure 134 is a dense structure in which each side of a hexagon (e.g., a regular hexagon) overlaps with one side of another hexagon, and excluding the corners, the honeycomb structure 134 has a regular arrangement in which one hexagon is surrounded by six other hexagons.

[0047] The honeycomb structure 134 is a typical structure that has high rigidity relative to its volume. By providing the honeycomb structure 134 on the surface of the partition member 130 of the present invention, it is possible to secure space for incorporating a large number of fire-extinguishing pads 170 while maintaining excellent rigidity of the partition member 130. This means that there is no need to make the partition member 130 thick enough to maintain mechanical rigidity while still being able to mount a sufficient number of fire-extinguishing pads 170. As a result, it is possible to effectively suppress and delay heat propagation while reducing the weight of the partition member 130 and the pack case 100 including the partition member 130.

[0048] 4 is a view showing another embodiment of the partition wall member 130, in which the groove structures 132 in the illustrated embodiment are provided as honeycomb structures 134 on both sides of the partition wall member 130. Since weight reduction is possible using the honeycomb structures 134, by slightly increasing the thickness of the partition wall member 130 and forming the honeycomb structures 134 on both sides of which fire-extinguishing pads 170 are attached, a fire occurring in the battery module 200 can be more effectively responded to.

[0049] Here, the honeycomb structures 134 provided on both sides of the partition member 130 may not be connected to each other. In this case, the honeycomb structures 134 on both sides of the partition member 130 may be alternately arranged at a half pitch P in the vertical and / or horizontal directions. Pitch refers to the vertical or horizontal distance between the regularly arranged hexagons that form the honeycomb structures 134. The honeycomb structures 134 on both sides of the partition member 130 are offset by a half pitch P in the vertical and / or horizontal directions so that they do not overlap, thereby further enhancing the rigidity of the entire partition member 130 due to the offset honeycomb structures 134 like a net. The partition member 130 illustrated in FIG. 4 shows an embodiment in which the honeycomb structures 134 on both sides are alternately arranged at a half pitch P in both the vertical and horizontal directions.

[0050] (Second embodiment) 5 and 6 each show an embodiment in which a fire suppression pad 170 is attached to the bulkhead member 130.

[0051] The embodiment of FIG. 5 relates to a method in which a fire-extinguishing pad 170 is separately provided so as to conform to the shape of the groove structure 132 provided in the partition member 130, and then the fire-extinguishing pad 170 is inserted into the groove structure 132 by adhesive bonding, fitting, or other methods.

[0052] For example, the fire extinguishing pad 170 can be manufactured using foam molding technology. That is, a porous pad 172 with numerous pores can be manufactured by mixing a foaming agent into a thermoplastic resin or the like, or by injecting a gas such as nitrogen during the molding process. In this case, capsules 174 containing a sealed liquid fire extinguishing agent 176 can be mixed into the resin used for molding, and foam molding can be performed to manufacture the fire extinguishing pad 170 with the structure shown in FIG. 3. By forming the mold used for foam molding in the shape of the groove structure 132 provided in the partition member 130, the fire extinguishing pad 170 can be manufactured to a precise size and shape.

[0053] 6 schematically illustrates an embodiment in which a fire-extinguishing pad 170 is attached using the partition member 130 itself, on which the groove structure 132 is formed, as a mold, without the need for a separate mold. Using the partition member 130 as a mold reduces mold costs and makes it possible to manufacture a partition member 130 with an integrated fire-extinguishing pad 170 that fits snugly into the groove structure 132 of the partition member 130, without the need for a separate assembly process. In particular, the embodiment of FIG. 6 is advantageous when multiple groove structures 132 are provided by ribs 134, or when the shape of the groove structures 132 is complex or the shapes of the multiple groove structures 132 are not identical.

[0054] (Third embodiment) FIG. 7 is a view showing a pack case 100 including a partition member 130 according to the first embodiment of the present invention.

[0055] The illustrated pack case 100 includes a base plate 110 forming the bottom surface, a side plate 120 surrounding the outer periphery of the base plate 110, a partition member 130 of the first embodiment arranged vertically and / or horizontally to partition the storage space limited by the side plate 120, and a lid 180 that closes the top surface of the storage space.

[0056] The partition member 130 described in detail above may have its bottom surface joined to the upper surface of the base plate 110 by laser welding, brazing, or the like, or may be joined by bolting, etc. In the embodiment shown in Fig. 7, the partition member 130 of the first embodiment forms the cross beam 150 of the pack case 100. Of course, as described above, the partition member 130 of the first embodiment may also be used as the center beam 140.

[0057] FIG. 8 is a diagram showing an embodiment of a battery pack 10 in which battery modules 200 are mounted in the pack case 100 of FIG. 7. The cross beams 150 equipped with fire extinguishing pads 170 are aligned so that the fire extinguishing pads 170 face the same direction, thereby assigning one fire extinguishing pad 170 to each battery module 200 (see FIGS. 7 and 8). By assigning one fire extinguishing pad 170 to each battery module 200, if thermal runaway occurs in a battery module 200, the fire extinguishing pad 170 assigned to that battery module 200 reacts thermally and ejects vaporized fire extinguishing agent 176, thereby actively suppressing the thermal runaway. The ejection of the fire extinguishing agent 176 reduces the temperature of the battery module 200, thereby delaying the thermal runaway. When viewed as a whole battery pack 10, the fire extinguishing pads 170 are activated sequentially in the direction of heat propagation, thereby maintaining the heat propagation delay effect for as long as possible.

[0058] FIG. 9 is a view showing another embodiment of a battery pack 10 in which battery modules 200 are mounted in the pack case 100 of FIG. 7. This embodiment is distinguished from the embodiment of FIG. 8 in that fire-extinguishing pads 170 are provided on both sides of the cross beam 150. By providing fire-extinguishing pads 170 on both sides of the battery modules 200, the amount of fire-extinguishing agent 176 that can solve the problem when a fire breaks out in a battery module 200 is doubled, thereby enabling more effective fire suppression. Here, FIG. 9 shows an embodiment in which two bulkhead members 130 with fire-extinguishing pads 170 on one side are stacked to form one cross beam 150. However, it should be obvious that the embodiment of FIG. 9 can also be realized by forming a cross beam 150 using one bulkhead member 130 with fire-extinguishing pads 170 on both sides, as described in the embodiment of FIG. 4.

[0059] The present invention has been described in more detail above through the drawings and embodiments, etc. However, the configurations described in the drawings or embodiments in this specification are merely one embodiment of the present invention and do not represent all of the technical ideas of the present invention, and therefore, there may be various equivalents and modifications that can replace them at the time of filing this application. [Explanation of symbols]

[0060] 10: Battery pack 100: Pack case 110: Base plate 120: Side plate 130: Partition member 132:Groove structure 134: Honeycomb structure 140: Center beam 150: Cross beam 180: Lid 170: Fire extinguishing pad 172: Porous pad 174: Capsule 176: Fire extinguishing agent 200: Battery module 210: Battery cell P: Pitch

Claims

1. A partition member installed between a plurality of battery modules mounted in a battery pack, At least one side surface of the partition member has a plurality of regularly aligned groove structures; A partition member in which fire extinguishing pads containing a fire extinguishing agent are installed within the plurality of groove structures.

2. The fire extinguishing pad is 2. The partition member of claim 1, comprising a porous pad, a plurality of capsules contained within said pad, and a liquid fire extinguishing agent sealed within said capsules.

3. The liquid fire extinguishing agent is The barrier member of claim 2 which is a fluorinated ketone.

4. The capsule comprises:

4. The partition member according to claim 3, which melts or bursts due to internal vapor pressure when the temperature of the fire-extinguishing pad is in the range of 120 to 220° C., thereby releasing the fire-extinguishing agent.

5. The extinguishing agent released from the capsule is The partition member according to claim 4 , wherein the air is released to the outside through pores of the porous pad.

6. The plurality of groove structures include: The partition member according to claim 1 , wherein the partition member has a honeycomb structure in which a plurality of hexagonal grooves are regularly aligned.

7. The honeycomb structure is The partition member according to claim 6 , wherein the partition member is provided on each of both side surfaces thereof.

8. The honeycomb structures provided on both side surfaces of the partition member are Without communicating with each other, The partition member according to claim 7 , wherein the partition members are alternately arranged at half pitch intervals along the longitudinal direction and / or the transverse direction.

9. A base plate and a side plate surrounding the outer periphery of the base plate; The partition member according to any one of claims 1 to 8, which is arranged vertically and / or horizontally so as to partition an accommodation space limited by the side plate; and a lid that closes the top surface of the storage space.

10. The partition member is 10. The pack case of claim 9, which is a cross beam.

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