Battery pack fire extinguisher

Abstract

A battery pack fire extinguisher includes: a plurality of battery cells; a bottom case accommodating the plurality of battery cells; a top case covering the plurality of battery cells and coupled to the bottom case; a fire extinguishing agent between an inner surface of the top case and one end of at least one battery cell of the plurality of battery cells; and a partition wall on an outer side of the fire extinguishing agent and protruding beyond the fire extinguishing agent toward the at least one battery cell of the plurality of battery cells.

Description

TECHNICAL FIELD

[0001] Aspects of an embodiment of the disclosure relate to a battery pack fire extinguisher. BACKGROUND

[0002] A battery pack includes a plurality of battery cells according to an intended application. For example, a battery pack for a home robot vacuum cleaner can include about 7 to about 14 battery cells, a battery pack for an electric bicycle can include about 20 battery cells, a battery pack for an electric scooter can include about 80 battery cells, and a battery pack for a light electric vehicle (LEV) can include about 200 battery cells.

[0003] The amount and location of the fire extinguishing agent used in the battery pack can vary according to the intended use or application of the battery pack. The amount of the fire extinguishing agent used can vary according to the capacity of each battery cell or the space (e.g., volume) of the battery pack, but generally, one fire extinguishing agent applied to about 25 battery cells (e.g., a space of 120 mm x 120 mm) can extinguish a fire of the battery cells.

[0004] If a plurality of fire extinguishing agents in the battery pack operate together (or simultaneously), the flame of the battery cell can spread due to heat generated by the ignition of the plurality of fire extinguishing agents in the battery pack.

[0005] In addition, if all the fire extinguishing agents are activated by the flame of the battery cell, if another flame occurs later in another battery cell, there will be no fire extinguishing agent operation, so that it is not possible to extinguish the flame that occurs later. SUMMARY

[0006] An embodiment of the disclosure provides a battery pack fire extinguisher that can prevent a fire from spreading to surrounding battery cells when a fire occurs in one battery cell.

[0007] An embodiment of the disclosure provides a battery pack fire extinguisher that can extinguish a fire by using a fire extinguishing agent for a cell group of battery cells when a fire occurs in the battery cell and can prevent the fire extinguishing agent outside the cell group from operating.

[0008] According to an embodiment of the disclosure, a battery pack fire extinguisher includes a plurality of battery cells, a bottom housing that accommodates the plurality of battery cells, a top housing that covers the plurality of battery cells and is coupled to the bottom housing, a fire extinguishing agent between an inner surface of the top housing and one end of at least one battery cell of the plurality of battery cells, and a partition wall outside the fire extinguishing agent and protruding beyond the fire extinguishing agent toward the at least one battery cell of the plurality of battery cells.

[0009] The partition wall can be configured to limit a flame inflow range of the fire extinguishing agent, and the flame inflow range can exclude a flame generated from some battery cells outside a cell group among the plurality of battery cells and can guide a flame generated from some battery cells within the cell group to the fire extinguishing agent.

[0010] The partition wall can be a rib of the top case configured to block a flame.

[0011] The partition wall can include a plastic resin, stainless steel, or aluminum.

[0012] The fire extinguishing agent can be formed in a circular plate, and the partition wall can be formed in a circular tube corresponding to the outer side of the fire extinguishing agent.

[0013] The fire extinguishing agent can have a through-hole in a portion corresponding to the at least one battery cell among the plurality of battery cells.

[0014] The fire extinguishing agent can be formed in a quadrangular plate, and the partition wall can be formed in a quadrangular tube corresponding to the outer side of the fire extinguishing agent.

[0015] The fire extinguishing agent can be formed in a hexagonal star plate, and the partition wall can be formed in a hexagonal star tube corresponding to the outer side of the fire extinguishing agent.

[0016] The fire extinguishing agent can be formed in a cross-shaped plate, and the partition wall can be formed in a cross-shaped tube corresponding to the outer side of the fire extinguishing agent.

[0017] The fire extinguishing agent can be formed in a triangular plate, and the partition wall can be formed in a triangular tube corresponding to the outer side of the fire extinguishing agent.

[0018] The fire extinguishing agent can have a thickness, and a height of the partition wall can be greater than the thickness of the fire extinguishing agent.

[0019] The outer side of the fire extinguishing agent can have a side surface perpendicularly intersecting the inner surface of the top case, and the partition wall can be inclined at an angle with respect to the side surface and can have an inclined surface having a minimum width at a top and a maximum width at a bottom with respect to a center line of the fire extinguishing agent.

[0020] The partition wall can surround at least one side of the outer side of the fire extinguishing agent when viewed in a cross-sectional view.

[0021] An upper end of the partition wall and the outer side of the fire extinguishing agent can have a gap therebetween.

[0022] The outer side of the fire extinguishing agent can have a side surface that perpendicularly intersects the inner surface of the top case, and the partition wall can be inclined at an angle with respect to the side surface and have an inclined surface that has a maximum width at a top and a minimum width at a bottom with respect to a center line of the fire extinguishing agent.

[0023] The outer side of the fire extinguishing agent can have a side surface that perpendicularly intersects the inner surface of the top case, the partition wall can have a vertical surface corresponding to the side surface and a convex curved surface extending from the vertical surface and convexly outward, and the convex curved surface can have a minimum width at a top and a maximum width at a bottom with respect to a center line of the fire extinguishing agent.

[0024] The convex curved surface can convexly surround at least one side of the outer side from below of the fire extinguishing agent when viewed in a cross-sectional view.

[0025] The outer side of the fire extinguishing agent can have a side surface that perpendicularly intersects the inner surface of the top case, the partition wall can have a vertical surface corresponding to the side surface and a concave curved surface extending from the vertical surface and concavely inward, and the concave curved surface can have a maximum width at a top and a minimum width at a bottom with respect to a center line of the fire extinguishing agent.

[0026] The concave curved surface can concavely surround at least one side of the outer side from below of the fire extinguishing agent when viewed in a cross-sectional view.

[0027] According to embodiments of the disclosure, a fire extinguishing agent is installed between an inner surface of a top case and a battery cell such that a flame from the battery cell is directed to the fire extinguishing agent to ignite the fire extinguishing agent, and a smoke (i.e., an aerosol spray material) generated by the fire extinguishing agent is introduced (or directed) into the battery cell to extinguish a fire.

[0028] According to embodiments of the disclosure, since the fire extinguishing agent is surrounded by the partition wall along a periphery thereof, a range of inflow of the flame to the fire extinguishing agent can be limited. For example, a flame generated from a battery cell in a corresponding cell group is introduced to the fire extinguishing agent, whereas a flame generated from a battery cell outside the cell group among the plurality of battery cells is not introduced to the fire extinguishing agent.

[0029] Accordingly, when a fire occurs in a battery cell, the fire extinguishing agent in a corresponding cell group of the battery cell can act as a fire extinguishing agent, and the fire extinguishing agent outside the cell group (e.g., corresponding to other cell groups) does not operate (or ignite) (prematurely).

[0030] Accordingly, when an initial fire occurs in a battery cell, the corresponding fire extinguishing agent in the unit group functions as a fire extinguishing agent. In addition, when a subsequent fire occurs in another battery cell, the other fire extinguishing agent in the other corresponding unit group operates and extinguishes the subsequent fire.

[0031] Accordingly, in various embodiments, a partition wall is provided around the fire extinguishing agent to limit the inflow range of the fire, so that even when multiple fires are generated at different times in the battery cells in the battery pack, the multiple fires can be effectively extinguished. BRIEF DESCRIPTION OF DRAWINGS

[0032] Figure 1 is a top plan view of a battery pack fire extinguisher according to an embodiment of the present disclosure.

[0033] Figure 2 is a cross-sectional view taken along line II-II in Figure 1 .

[0034] Figure 3 is a partial cross-sectional view of the battery pack fire extinguisher shown in Figure 1 .

[0035] Figure 4 is a top plan view of a battery pack fire extinguisher according to another embodiment of the present disclosure.

[0036] Figure 5 is a top plan view of the fire extinguishing agent and partition wall in Figure 4 .

[0037] Figure 6 is a front view of Figure 4 .

[0038] Figure 7A is a top plan view of a fire extinguishing agent and partition wall applied to a battery pack fire extinguisher according to another embodiment of the present disclosure.

[0039] Figure 7B is a perspective view of the battery pack fire extinguisher shown in Figure 7A .

[0040] Figure 8 is a top plan view of a fire extinguishing agent and partition wall applied to a battery pack fire extinguisher according to another embodiment of the present disclosure.

[0041] Figure 9 is a top plan view of a fire extinguishing agent and partition wall applied to a battery pack fire extinguisher according to another embodiment of the present disclosure.

[0042] Figure 10 is a top plan view of a fire extinguishing agent and partition wall applied to a battery pack fire extinguisher according to another embodiment of the present disclosure.

[0043] Figure 11is a cross-sectional view of a fire extinguishing agent and a partition wall applied to a battery pack fire extinguisher according to another embodiment of the disclosure.

[0044] Figure 12 is a cross-sectional view of a fire extinguishing agent and a partition wall applied to a battery pack fire extinguisher according to another embodiment of the disclosure.

[0045] Figure 13 is a cross-sectional view of a fire extinguishing agent and a partition wall applied to a battery pack fire extinguisher according to another embodiment of the disclosure.

[0046] Figure 14 is a cross-sectional view of a fire extinguishing agent and a partition wall applied to a battery pack fire extinguisher according to another embodiment of the disclosure.

[0047] Figure 15 is a cross-sectional view of a fire extinguishing agent and a partition wall applied to a battery pack fire extinguisher according to another embodiment of the disclosure.

[0048] Figure 16 is a cross-sectional view of a fire extinguishing agent and a partition wall applied to a battery pack fire extinguisher according to another embodiment of the disclosure.

[0049] Figure 17 is a cross-sectional view of a fire extinguishing agent and a partition wall applied to a battery pack fire extinguisher according to another embodiment of the disclosure.

[0050] Figure 18 is a cross-sectional view of a fire extinguishing agent and a partition wall applied to a battery pack fire extinguisher according to another embodiment of the disclosure.

[0051] BRIEF DESCRIPTION OF DRAWINGS

[0052] 1, 2, 3, 4, 5, 6, 7, 8, 9: battery pack fire extinguisher

[0053] 10: battery cell 11: exhaust port

[0054] 20: bottom housing 30: top housing

[0055] 40: fire extinguishing agent 41: through hole

[0056] 100, 101, 102, 103, 104: battery pack fire extinguisher

[0057] 50: partition wall 240: fire extinguishing agent

[0058] 340: fire extinguishing agent 350: partition wall

[0059] 411: tapered surface 440: fire extinguishing agent

[0060] 450: partition wall 540: fire extinguishing agent

[0061] 550: partition wall 640: fire extinguishing agent

[0062] 650: partition wall 740: fire extinguishing agent

[0063] 750: partition wall 840: fire extinguishing agent

[0064] 850: partition wall 940: fire extinguishing agent

[0065] 950: partition wall 1040: fire extinguishing agent

[0066] 1050: partition wall 1051: vertical surface

[0067] 1052: convex curved surface 1140: fire extinguishing agent

[0068] 1150: partition wall 1240: fire extinguishing agent

[0069] 1250: partition wall 1251: vertical surface

[0070] 1252: concave curved surface

[0071] 1350: partition wall

[0072] 1340: fire extinguishing agent F1: first flame

[0073] F2: second flame G: gap

[0074] G2: gap H: height

[0075] P1: first surface P2: second surface

[0076] t: thickness UG: unit group

[0077] UG1, UG2, UG3, UG4: first, second, third, fourth unit group

[0078] W: width W1: minimum width

[0079] W2: maximum width W11: maximum width

[0080] W21: minimum width W21: maximum width

[0081] W22: minimum width W31: minimum width

[0082] W32: maximum width W41: minimum width

[0083] W42: maximum width θ: angle

[0084] θ2: angle Φ1: first diameter

[0085] Φ2: second diameter DETAILED DESCRIPTION

[0086] The present disclosure will be described more fully below with reference to the accompanying drawings, in which embodiments of the present disclosure are shown. As will be appreciated by those skilled in the art, the described embodiments may be modified in various ways without departing from the scope of the present disclosure. The drawings and description are to be considered illustrative and non-restrictive in nature.

[0087] It will be understood that when an element or layer is referred to as being “on,” “connected to,” or “coupled to” another element or layer, it can be directly on, connected to, or coupled to the other element or layer, or one or more intervening elements or layers may also be present. When an element or layer is referred to as being “directly on,” “directly connected to,” or “directly coupled to” another element or layer, there are no intervening elements or layers. For example, when a first element is described as being “coupled to” or “connected to” a second element, the first element can be directly coupled or connected to the second element, or the first element can be indirectly coupled or connected to the second element via one or more intervening elements.

[0088] In the accompanying drawings, the sizes of various elements, layers, etc. may be exaggerated for clarity of illustration. The same reference numerals represent the same elements. As used herein, the term "and / or" includes any and all combinations of one or more of the associated listed items. In addition, the use of "may" when describing an embodiment of the present disclosure relates to "one or more embodiments of the present disclosure." Expressions such as "at least one of..." and "any one of..." modify the entire list of elements when following a list of elements, without modifying a single element in the list. For example, the expression "at least one of a, b, and c" represents only a, only b, only c, a and b, a and c, b and c, a, b, and c, or all or variations thereof. As used herein, the term "using" may be considered to be synonymous with the term "utilizing." As used herein, the terms "substantially," "about," and similar terms are used as approximate terms rather than terms of degree, and are intended to take into account the inherent variations of measurements or calculated values ​​that will be recognized by those of ordinary skill in the art.

[0089] It will be understood that although the terms "first," "second," "third," etc. may be used herein to describe various elements, components, regions, layers, and / or sections, these elements, components, regions, layers, and / or sections should not be limited by these terms. These terms are used to distinguish one element, component, region, layer, or section from another element, component, region, layer, or section. Thus, a first element, component, region, layer, or section discussed below could be termed a second element, component, region, layer, or section without departing from the teachings of the example embodiments.

[0090] For ease of description, spatially relative terms such as "beneath", "below", "lower", "above", "upper" and the like can be used herein for describing an element's or feature's relationship to another element(s) or feature(s) as illustrated in the figures. It will be understood that the spatially relative terms are intended to encompass different orientations of the device in use or operation in addition to the orientation depicted in the figures. For example, if a device in the figures is inverted, elements described as "below" or "beneath" other elements or features would then be oriented "above" the other elements or features. Thus, the term "below" can encompass both an orientation of above and below. The devices can be otherwise oriented (rotated 90 degrees or at other orientations) and the spatially relative descriptors used herein interpreted accordingly.

[0091] The terminology used herein is for the purpose of describing embodiments of the present disclosure and is not intended to be limiting of the present disclosure. As used herein, the singular forms "a", "an" and "the" are intended to include the plural forms as well, unless the context clearly indicates otherwise. It will be further understood that the terms "comprises" and / or "comprising", when used in this specification, specify the presence of stated features, integers, steps, operations, elements, and / or components, but do not preclude the presence or addition of one or more other features, integers, steps, operations, elements, components, and / or groups thereof.

[0092] In view of the entire disclosure, those of ordinary skill in the art will appreciate that each suitable feature of various embodiments of the present disclosure can be partially or wholly combined or with each other, and can be technically interlocked and operated in various suitable ways, and each embodiment can be implemented independently of each other or in combination with each other in any suitable way, unless otherwise specified or implied.

[0093] When a fire occurs in one battery cell of a battery pack including a plurality of battery cells, a fire extinguishing agent (or a fire extinguishing device) is used to extinguish the fire and prevent the fire from spreading to other battery cells in the battery pack. The fire extinguishing agent extinguishes the fire caused by the fire in the battery pack. The fire extinguishing agent embedded in the battery pack extinguishes the fire and prevents the fire from spreading in the shortest possible time.

[0094] Prismatic or circular battery cells can be used in the battery pack. To prevent chain ignition of the battery cells, the battery pack includes a fire extinguishing agent. The fire extinguishing agent is installed in a structure in consideration of the operating characteristics at the upper portion (or upper end) of the battery cell as a fire source.

[0095] The fire extinguishing agent is configured to be ignited by the flame of the ignited battery cell and to burn to generate a smoke, i.e., an aerosol spray material, to extinguish the flame of the battery cell with the aerosol spray material.

[0096] The battery pack is configured such that when a first fire (or initial fire) of a battery cell occurs, the fire extinguishing agent of the unit group functions as a fire extinguishing agent, and if a fire occurs in another battery cell at a later time (e.g., a time interval), the fire extinguishing agent of another unit group operates to extinguish the later fire.

[0097] Figure 1 is a top plan view of a battery pack fire extinguisher according to an embodiment of the disclosure, and Figure 2 is a cross-sectional view taken along line II-II in Figure 1 .

[0098] Referring to Figure 1 and Figure 2 , a battery pack fire extinguisher 1 according to an embodiment includes a plurality of battery cells 10, a bottom housing 20 accommodating the battery cells 10, a top housing 30 coupled to the bottom housing 20, a fire extinguishing agent 40 provided between the top housing 30 and the battery cells 10, and a partition wall 50 provided outside the fire extinguishing agent 40 (e.g., extending around a periphery of the fire extinguishing agent 40). The top housing 30 can cover the plurality of battery cells 10. In an embodiment, the fire extinguishing agent 40 can be provided between an inner surface of the top housing 30 and one end of at least one of the plurality of battery cells 10.

[0099] The battery cells 10 can be prismatic rechargeable batteries or cylindrical rechargeable batteries. The bottom housing 20 and the top housing 30 can have various sizes according to the capacity and size of the battery cells 10. The battery pack can be formed by connecting tens to hundreds of the battery cells 10 in series, in parallel, or in a mixed connection of series and parallel. The temperature at which the fire extinguishing agent 40 ignites can be in the range of about 380°C to about 400°C, and in one embodiment, can be about 390°C.

[0100] The fire extinguishing agent 40 is configured to perform a more efficient combustion operation at an initial stage at which the battery cells 10 ignite. Accordingly, the exhaust port 11 of the battery cells 10 is oriented toward the top housing 30 such that the fire extinguishing agent 40 is disposed between the exhaust port 11 and the top housing 30 to achieve a fire extinguishing effect.

[0101] According to the structure of the battery pack, the fire extinguishing agent 40 can be installed corresponding to the exhaust port 11 of the battery cells 10, or can be installed at a position away (e.g., vertically and / or horizontally offset) from the exhaust port 11. The battery cells 10 are disposed in unit groups UG, and the fire extinguishing agent 40 is disposed in each unit group UG one by one (e.g., one fire extinguishing agent 40 is disposed in each unit group UG). In Figure 1In the battery pack fire extinguisher 1 illustrated in FIG. 1, the battery cells 10 are arranged (e.g., form) in a first cell group UG1, a second cell group UG2, a third cell group UG3, and a fourth cell group UG4. The fire extinguant 40 has a thickness t.

[0102] The partition wall 50 is provided outside the fire extinguant 40 and has a height H that protrudes from the fire extinguant 40 toward the battery cells 10. The height of the partition wall 50 is greater than the thickness t of the fire extinguant 40. Accordingly, the partition wall 50 directs a flame generated from the battery cells 10 to the fire extinguant 40 and directs the smoke (i.e., aerosol spray material) generated by the ignition combustion of the fire extinguant 40 toward the flame of the battery cells 10.

[0103] For example, the partition wall 50 limits the inflow range of the flame to the fire extinguant 40. The inflow range is set (or configured) to introduce the flame generated in the battery cells 10 in the cell group UG to the fire extinguant 40, while excluding the flame generated in the battery cells 10 outside the cell group UG among the plurality of battery cells 10.

[0104] For example, the partition wall 50 can be formed as a rib (e.g., a rib extending from the top case 30) configured to block the flame. The partition wall 50 can be formed of the same material as that of the top case 30, such as a plastic resin, thereby avoiding an increase in the number of components. In other embodiments, the partition wall 50 can be made of stainless steel or aluminum and can be advantageous for the ignition of the fire extinguant 40 due to its high heat conductivity.

[0105] In the illustrated embodiment, since the fire extinguant 40 is formed as a circular plate, the partition wall 50 is formed as a circular tube corresponding to (e.g., extending around) the outer side of the fire extinguant 40. The circular tube partition wall 50 tightly accommodates the circular plate fire extinguant 40, thereby enabling firm and stable installation of the fire extinguant 40.

[0106] Figure 3 is Figure 1 A partial cross-sectional view of the battery pack fire extinguisher illustrated in FIG. 1. Reference is made to Figures 1-3 When a first flame (or initial flame) Fl is generated in the battery cells 10 of the first cell group UG1, the flame is directed by the partition wall 50 to the fire extinguant 40 of the first cell group UG1 to ignite the fire extinguant in the first cell group UG1.

[0107] In this case, the generated first flame Fl is not directed by the partition wall 50 of the fire extinguant 40 of the adjacent second cell group UG2 to the fire extinguant 40. Accordingly, the fire extinguant 40 of the second cell group UG2 is not ignited (e.g., remains in a state where an ignition operation does not occur).

[0108] In addition, the smoke (i.e., aerosol spray material) generated by the ignition of the fire extinguishing agent 40 in the first unit group UG1 is guided by the partition wall 50 to the battery cells 10 in the first unit group UG1 to extinguish the first fire F1.

[0109] In this case, the generated smoke (i.e., aerosol spray material) is not guided by the partition wall 50 to the battery cells 10 in the adjacent second unit group UG2. For example, the battery cells 10 of the second unit group UG2 are not affected by the smoke (i.e., aerosol spray material) emitted from the fire extinguishing agent 40 of the first unit group UG1.

[0110] Accordingly, when the first fire F1 occurs in the battery cells 10 in the first unit group UG1, the first fire F1 is guided to the fire extinguishing agent 40 in the first unit group UG1 due to the guiding action of the partition wall 50, and the fire extinguishing agent 40 extinguishes the fire F1 using the smoke generated by the ignition of the fire extinguishing agent 40.

[0111] In addition, when a second fire (or subsequent fire) F2 occurs later in the battery cells 10 in the second unit group UG2, the second fire F2 is guided to the fire extinguishing agent 40 in the second unit group UG2 due to the guiding action of the partition wall 50, and the fire extinguishing agent 40 extinguishes the fire F2 using the smoke generated by the ignition of the fire extinguishing agent 40 in the second unit group UG2.

[0112] As described above, the partition wall 50 surrounding the fire extinguishing agent 40 limits the inflow range of the first fire F1 and the second fire F2, so that the first fire F1 and the second fire F2 can be effectively extinguished even when a plurality of first fires F1 and second fires F2 occur at different times in the battery cells 10 in the battery pack.

[0113] Hereinafter, various embodiments of the present disclosure will be described. In comparison with the embodiments described above, the following embodiments will be mainly described, and the description of the same or substantially similar parts can be omitted or only briefly described, and the description of different parts will be mainly described.

[0114] Figure 4 is a top plan view of a battery pack fire extinguisher according to another embodiment of the present disclosure, Figure 5 is Figure 4 is a top plan view of a fire extinguishing agent and a partition wall shown in Figure 6 is Figure 4 is a front view of

[0115] Referring to Figures 4-6 In the battery pack fire extinguisher 2 according to an embodiment, the fire extinguishing agent 240 has a through hole (e.g., an opening) 41 in a portion thereof corresponding to the battery cells 10. The present embodiment also includes the partition wall 50 described above.

[0116] In the illustrated embodiment, the partition wall 50 guides the flames and the smoke (i.e., the aerosol spray material), and the through-hole 41 has a further role.

[0117] The through-hole 41 is disposed to correspond to the exhaust port 11 of the battery cell 10, which exhausts the first flame F1 and the second flame F2 generated in the battery cell 10. The first flame F1 and the second flame F2 can reach the top case 30 (see, for example, FIG. 2) and form a hole (e.g., an opening) in the top case 30. Figure 2 ) and form a hole (e.g., an opening) in the top case 30.

[0118] The through-hole 41 allows the first flame F1 and the second flame F2 to pass therethrough, which reduces the reflection of the first flame F1 and the second flame F2 from the fire extinguishing agent 240 around the through-hole 41, and can minimize the heat generated during ignition of the fire extinguishing agent 240.

[0119] The through-hole 41 in the fire extinguishing agent 240 corresponding to the exhaust port 11 can be formed by removing a portion of the fire extinguishing agent 240. For example, since the portion of the fire extinguishing agent corresponding to the through-hole 41 is removed, the amount of the fire extinguishing agent 240 is reduced, as a result of which the heat generated when the fire extinguishing agent 240 ignites is reduced, i.e., the ignition heat can be reduced.

[0120] In addition, to reduce or minimize the reflection of the first flame F1 and the second flame F2 and reduce the ignition heat of the fire extinguishing agent 240, the through-hole 41 can have an inclined surface. In more detail, the fire extinguishing agent 240 has a thickness t, and the through-hole 41 has a first diameter Φ1 at a first surface (e.g., a top surface) P1 facing the top case 30 and a second diameter Φ2 greater than the first diameter Φ1 at a second surface (e.g., a lower surface) P2 facing the battery cell 10. The second diameter Φ2 can be greater than the diameter of the exhaust port 11 to effectively guide the first flame F1 and the second flame F2.

[0121] For example, the first diameter Φ1 can be the same as the size (i.e., diameter) of the exhaust port 11 of the battery cell 10, and the second diameter Φ2 can be twice the size (i.e., diameter) of the exhaust port 11. The through-hole 41 is connected to a tapered surface 411 from the first diameter Φ1 to the second diameter Φ2 (e.g., the through-hole 41 can be formed by or have the tapered surface 411).

[0122] Accordingly, the first flame F1 and the second flame F2 generated in the battery cell 10 are minimally reflected by the second diameter Φ2 of the through-hole 41, and the second diameter Φ2 thereof makes the through-hole 41 relatively large, thereby reducing the amount of the fire extinguishing agent 240 to reduce or minimize the ignition heat.

[0123] Further, since the through-hole 41 narrows from the second diameter Φ2 to the first diameter Φ1, the first flame F1 and the second flame F2 are trapped within the tapered surface 411 of the fire extinguishing agent 240, thereby preventing them from returning to the battery cell 10 (e.g., turning toward the battery cell 10).

[0124] For example, since the first flame F1 and the second flame F2 are temporarily trapped in the through-hole 41, the heat and time required to operate the fire extinguishing agent 240 (e.g., as a potassium solid compound) can be ensured. Accordingly, the fire extinguishing agent 240 can be more effectively ignited by the first flame F1 and the second flame F2 trapped in the through-hole 41.

[0125] When the battery cell 10 emits flames in the battery pack fire extinguisher 2 according to the present embodiment, the first flame F1 and the second flame F2 travel toward the fire extinguishing agent 240 disposed above the exhaust port 11 and travel to the top housing 30 through the through-hole 41.

[0126] The first flame F1 and the second flame F2 entering the through-hole 41 are temporarily trapped in the through-hole 41 by the tapered surface 411 and stay there. Since the first flame F1 and the second flame F2 cannot return to the battery cell 10 (e.g., cannot turn toward the battery cell 10), the temperature of the battery cell 10 does not rise.

[0127] The first flame F1 and the second flame F2 in the through-hole 41 ignite the fire extinguishing agent 240 by supplying sufficient time heat to ensure the operation of the fire extinguishing agent 240. The smoke (i.e., aerosol spray material) generated by the ignition of the fire extinguishing agent 240 is supplied to the battery cell 10 to extinguish the first flame F1 and the second flame F2.

[0128] In this case, the first flame F1 and the second flame F2 trapped in the through-hole 41 cause complete combustion of the fire extinguishing agent 240. The sufficient combustion of the fire extinguishing agent 240 generates sufficient smoke (i.e., aerosol spray material), thereby further improving the fire extinguishing performance of the battery cell 10.

[0129] The partition wall 50 is provided outside the fire extinguishing agent 240 and has a height H protruding from the fire extinguishing agent 240 toward the battery cell 10. Accordingly, the partition wall 50 guides the first flame F1 and the second flame F2 generated in the battery cell 10 to the fire extinguishing agent 240 and the through-hole 41, and guides the smoke (i.e., aerosol spray material) generated by the ignition combustion of the fire extinguishing agent 240 to the first flame F1 and the second flame F2 of the battery cell 10.

[0130] For example, the partition wall 50 limits the inflow range of the first flame F1 and the second flame F2 to the fire extinguishing agent 240. The inflow range is set to flow the first flame F1 and the second flame F2 generated in the battery cells 10 in the corresponding cell group UG, and to separate the first flame F1 and the second flame F2 generated in the battery cells 10 outside the corresponding cell group UG among the plurality of battery cells 10.

[0131] That is, when the first flame F1 is generated in the battery cells 10 of the first cell group UG1, the first flame F1 is guided by the partition wall 50 to the fire extinguishing agent 240 and the through hole 41 of the first cell group UG1 to ignite the fire extinguishing agent 240 in the first cell group UG1.

[0132] In this case, the generated first flame F1 is not guided by the partition wall 50 and the through hole 41 to the fire extinguishing agent 240 of the adjacent second cell group UG2. Accordingly, the fire extinguishing agent 240 of the second cell group UG2 is not ignited.

[0133] In addition, the smoke (i.e., aerosol spray material) generated by the ignition of the fire extinguishing agent 240 in the first cell group UG1 is guided by the partition wall 50 and the through hole 41 to the battery cells 10 in the first cell group UG1 to extinguish the first flame F1.

[0134] In this case, the generated smoke (i.e., aerosol spray material) is not guided by the partition wall 50 and the through hole 41 to the battery cells 10 in the adjacent second cell group UG2. In other words, the battery cells 10 of the second cell group UG2 are not affected by the smoke (i.e., aerosol spray material) emitted from the fire extinguishing agent 240 of the first cell group UG1.

[0135] Figure 7A is a top plan view of a fire extinguishing agent and a partition wall applied to a battery pack fire extinguisher according to another embodiment of the disclosure, and Figure 7B is Figure 7A is a perspective view of the battery pack fire extinguisher shown in

[0136] Referring to Figure 7A and Figure 7B , the battery pack fire extinguisher 3 according to another embodiment includes a fire extinguishing agent 340 that is a quadrangular plate and a partition wall 350 that is a quadrangular tube corresponding to the outer side of the fire extinguishing agent 340.

[0137] The fire extinguishing agent 340 and the partition wall 350 correspond to the shape of the arrangement BA of the battery cells 10. The quadrangular tube partition wall 350 closely accommodates the quadrangular plate fire extinguishing agent 340, thereby being able to firmly and stably mount the fire extinguishing agent 340.

[0138] For example, when the arrangement BA of the circular battery cells 10 is a quadrilateral, the quadrilateral plate extinguishing agent 340 ensures a constant or substantially constant distance from the battery cells 10 in the quadrilateral arrangement, and the quadrilateral tube partition wall 350 corresponds to the extinguishing agent 340 and the battery cells 10 of the unit group UG71 corresponding to the extinguishing agent 340.

[0139] Accordingly, the extinguishing agent 340 extinguishes the flames F generated in the battery cells 10 in the unit group UG71. However, the extinguishing agent 340 does not extinguish the flames F generated from the battery cells 10 of the adjacent unit groups UG72 and UG73.

[0140] Figure 8 is a top plan view of an extinguishing agent and a partition wall applied to a battery pack fire extinguisher according to another embodiment of the disclosure. Referring to Figure 8 , the battery pack fire extinguisher 4 according to another embodiment includes an extinguishing agent 440 formed as a hexagonal star-shaped plate and a partition wall 450 formed as a hexagonal star-shaped tube corresponding to the outer side of the extinguishing agent 440.

[0141] The extinguishing agent 440 and the partition wall 450 correspond to the shape of the arrangement of the battery cells 10. The hexagonal star-shaped tube partition wall 450 closely accommodates the hexagonal star-shaped plate extinguishing agent 440, thereby enabling the extinguishing agent 440 to be firmly and stably installed.

[0142] For example, when the arrangement of the circular battery cells 10 is a hexagonal star shape, the hexagonal star-shaped plate extinguishing agent 440 ensures a constant or substantially constant distance from the battery cells 10 in the hexagonal star-shaped arrangement, and the hexagonal star-shaped tube partition wall 450 corresponds to the extinguishing agent 440 and the battery cells 10 in the corresponding area.

[0143] Figure 9 is a top plan view of an extinguishing agent and a partition wall applied to a battery pack fire extinguisher according to another embodiment of the disclosure. Referring to Figure 9 , the battery pack fire extinguisher 5 according to another embodiment includes an extinguishing agent 540 formed as a cross-shaped plate having a width W and a partition wall 550 formed as a cross-shaped tube corresponding to the outer side of the extinguishing agent 540.

[0144] The extinguishing agent 540 and the partition wall 550 correspond to the shape of the arrangement of the battery cells 10. The cross-shaped tube partition wall 550 closely accommodates the cross-shaped plate extinguishing agent 540, thereby enabling the extinguishing agent 540 to be firmly and stably installed.

[0145] For example, when the arrangement of the circular battery cells 10 is a cross shape, the cross-shaped plate extinguishing agent 540 ensures a constant or substantially constant distance from the battery cells 10 in the cross-shaped arrangement, and the cross-shaped tube partition wall 550 corresponds to the extinguishing agent 540 and the battery cells 10 in the corresponding area.

[0146] Figure 10 is a top plan view of a fire extinguishing agent and a partition wall applied to a battery pack fire extinguisher according to another embodiment of the disclosure. Referring to Figure 10 , a battery pack fire extinguisher 6 according to another embodiment includes a fire extinguishing agent 640 formed in a triangular shape and a partition wall 650 formed in a triangular tube corresponding to the outer side of the fire extinguishing agent 640.

[0147] The fire extinguishing agent 640 and the partition wall 650 correspond to the shape of the arrangement of the battery cells 10. The triangular tube partition wall 650 closely accommodates the triangular plate fire extinguishing agent 640, thereby enabling the fire extinguishing agent 640 to be firmly and stably installed.

[0148] For example, when the arrangement of the circular battery cells 10 is triangular, the triangular plate fire extinguishing agent 640 ensures a constant or substantially constant distance from the triangularly arranged battery cells 10, and the triangular tube partition wall 650 corresponds to the fire extinguishing agent 640 and the battery cells 10 in the corresponding area.

[0149] Figure 11 is a cross-sectional view of a fire extinguishing agent and a partition wall applied to a battery pack fire extinguisher according to another embodiment of the disclosure. Referring to Figure 11 , a battery pack fire extinguisher 7 according to another embodiment includes a fire extinguishing agent 740 having a thickness t and a partition wall 750 having a total (e.g., overall) height H2 (H2 > t) greater than the thickness t.

[0150] The outer side of the fire extinguishing agent 740 has a side surface that perpendicularly intersects (or extends) the inner surface of the top housing 30 (e.g., see Figure 2 ). The partition wall 750 is inclined at an angle θ with respect to the side surface and has an inclined surface having a minimum width W1 at the top and a maximum width W2 at the bottom with respect to the center line of the fire extinguishing agent 740.

[0151] When the partition wall 750 is divided into two halves (e.g., divided into two halves based on the center line of the fire extinguishing agent 740), the partition wall 750 can have a structure surrounding both sides or the entire outer side of the fire extinguishing agent 740. The upper end of the partition wall 750 and the outer side of the fire extinguishing agent 740 can have a gap G therebetween.

[0152] Accordingly, the partition wall 750 guides the flame generated from the battery cells 10 (e.g., see Figure 2 ) to the fire extinguishing agent 740 and guides the smoke (i.e., aerosol spray material) generated by the ignition combustion of the fire extinguishing agent 740 to the flame of the battery cells 10.

[0153] The difference between the minimum width W1 and the maximum width W2 of the partition wall 750 can be such that the partition wall 750 effectively guides the flame and effectively determines (or controls) the ejection of the aerosol spray material. Since the gap G allows some of the flame to travel past the fire extinguishing agent 740, it can prevent the flame from reflecting off the partition wall 750 and the fire extinguishing agent 740 and flowing back into the battery cell 10.

[0154] Figure 12 is a cross-sectional view of a fire extinguishing agent and a partition wall applied to a battery pack fire extinguisher according to another embodiment of the disclosure. Referring to Figure 12 , the battery pack fire extinguisher 8 according to another embodiment includes a partition wall 850 having a structure that surrounds one side of the outside of a fire extinguishing agent 840 when the partition wall 850 is divided in half (e.g., divided into two parts based on the center line of the fire extinguishing agent 840).

[0155] Due to the outer wall of the top case 30 (e.g., see Figure 2 ), the partition wall can not be provided at (or near) a portion of the battery cell 10 where it is less likely that a flame will occur. For example, the partition wall 850 is provided only on one side of the outside of the fire extinguishing agent 840. Accordingly, compared to the partition wall 750 of the above-described embodiment, the partition wall 850 according to the present embodiment can reduce the amount of material required.

[0156] Figure 13 is a cross-sectional view of a fire extinguishing agent and a partition wall applied to a battery pack fire extinguisher according to another embodiment of the disclosure. Referring to Figure 13 , in the battery pack fire extinguisher 9 according to another embodiment, the outside of the fire extinguishing agent 940 forms a side surface that perpendicularly intersects (or extends) the inner surface of the top case 30 (e.g., see Figure 2 ).

[0157] The partition wall 950 is inclined at an angle θ2 with respect to the side surface and has an inclined surface having a maximum width W21 at the top and a minimum width W22 at the bottom with respect to the center line of the fire extinguishing agent 940.

[0158] When the partition wall 950 is divided in half (e.g., divided into two parts based on the center line of the fire extinguishing agent 940), it can have a structure that surrounds both sides or the entire outer circumference of the fire extinguishing agent 940. The upper end of the partition wall 950 and the outer circumference of the fire extinguishing agent 940 can have a gap G therebetween.

[0159] Accordingly, the partition wall 950 according to the present embodiment effectively guides the flame and effectively determines (or controls) the ejection of the aerosol spray material from the battery cell 10 (e.g., see Figure 2The performance of the flame generated by the fire barrier 950 according to the present embodiment is slightly inferior to that of the fire barrier 750 of the above-described embodiment in guiding the flame to the performance of the fire extinguishing agent 940, but can be superior to that of the fire barrier 750 of the above-described embodiment in guiding the smoke (i.e., aerosol spray material) generated by the ignition combustion of the fire extinguishing agent 940 to the flame of the battery cell 10.

[0160] In addition, the difference between the maximum width W21 and the minimum width W22 of the fire barrier 950 can enable the fire barrier 950 to effectively prevent the fire extinguishing agent 940 from falling (e.g., dropping and falling) toward the battery cell 10. Since the gap G2 allows some of the flame to travel, it is possible to prevent the flame from being reflected from the fire barrier 950 and the fire extinguishing agent 940 and flowing back into the battery cell 10.

[0161] Figure 14 is a cross-sectional view applied to a fire extinguishing agent and a fire barrier of a battery pack fire extinguisher according to another embodiment of the present disclosure. Referring to Figure 14 , the battery pack fire extinguisher 100 according to another embodiment includes a fire barrier 1050 having a structure around one side of the outside of the fire extinguishing agent 1040 when the fire barrier 1050 is divided into two halves (e.g., divided into two parts based on the center line of the fire extinguishing agent 1040).

[0162] Due to the outer wall of the top case 30 (e.g., see Figure 2 ), the fire barrier can not be provided at a portion of the battery cell 10 where the flame is less likely to occur. For example, the fire barrier 1050 is provided only on one side of the outside of the fire extinguishing agent 1040. Accordingly, the fire barrier 1050 according to the present embodiment can reduce the required material compared to the fire barrier 950 according to the above-described embodiment.

[0163] Figure 15 is a cross-sectional view applied to a fire extinguishing agent and a fire barrier of a battery pack fire extinguisher according to another embodiment of the present disclosure. Referring to Figure 15 , in the battery pack fire extinguisher 101 according to another embodiment, the outside of the fire extinguishing agent 1040 has a side surface that perpendicularly intersects (or extends) the inner surface of the top case 30 (e.g., see Figure 2 ). The fire barrier 1050 has a vertical surface 1051 corresponding to the side surface and a convex curved surface 1052 connected to (e.g., extending from) the vertical surface 1051 and convexly protruding outward (e.g., away from the fire extinguishing agent 1040).

[0164] The vertical surface 1051 can stably fix the fire extinguishing agent 1040. The convex curved surface 1052 guides the flame generated by the ignition combustion of the fire extinguishing agent 1040 to the battery cell 10 (e.g., see Figure 2) produced by the ignition combustion of the aerosol spray material by the fire extinguishing agent 1040 to the flame of the battery cell 10.

[0165] In addition, the convex curved surface 1052 has a minimum width W31 at the top and a maximum width W32 at the bottom with respect to the center line of the fire extinguishing agent 1040. When the convex curved surface 1052 is divided into two parts based on the center line of the fire extinguishing agent 1040, the partition wall 1050 can have a structure that protrudes from below the fire extinguishing agent 1040 to surround both sides of the outer side of the fire extinguishing agent 1040.

[0166] Accordingly, the difference between the minimum width W31 and the maximum width W32 of the convex curved surface 1052 can effectively guide the flame from the battery cell 10 to the fire extinguishing agent 1040 and effectively guide the aerosol spray material from the fire extinguishing agent 1040 to the battery cell 10.

[0167] Figure 16 is a cross-sectional view applied to a fire extinguishing agent and a partition wall of a battery pack fire extinguisher according to another embodiment of the disclosure. Referring to Figure 16 In the battery pack fire extinguisher 102 according to another embodiment, when the partition wall 1150 is divided into two parts based on the center line of the fire extinguishing agent 1140, the partition wall 1150 can have a structure that protrudes from below the fire extinguishing agent 1140 to surround one side of the outer side of the fire extinguishing agent 1140.

[0168] Due to the outer wall of the top case 30 (for example, see Figure 2 ), the partition wall can not be provided at a portion of the battery cell 10 where the flame is less likely to occur. For example, the partition wall 1150 is provided only on one side of the outer side of the fire extinguishing agent 1140. Accordingly, compared to the partition wall 1050 according to the above-described embodiment, the partition wall 1150 according to the present embodiment can reduce the required material.

[0169] Figure 17 is a cross-sectional view applied to a fire extinguishing agent and a partition wall of a battery pack fire extinguisher according to another embodiment of the disclosure. Referring to Figure 17 In the battery pack fire extinguisher 103 according to another embodiment, the outer side of the fire extinguishing agent 1240 has a side surface that perpendicularly intersects (or extends) the inner surface of the top case 30 (for example, see Figure 2 ). The partition wall 1250 has a vertical surface 1251 corresponding to the side surface and a concave curved surface 1252 connected to the vertical surface 1251 and recessed inward (for example, toward the fire extinguishing agent 1240).

[0170] The vertical surface 1251 can stably fix the fire extinguishing agent 1240. The concave curved surface 1252 guides the aerosol spray material from the battery cell 10 (for example, see Figure 2) produced from the battery cell 10 (for example, see

[0171] Accordingly, in terms of performance of guiding the flame produced from the battery cell 10 (for example, see Figure 2 ) to the fire extinguishing agent 1240, the partition wall 1250 according to the present embodiment is slightly lower than the partition wall 1050 according to the above-described embodiment, but in terms of performance of guiding the smoke (i.e., aerosol spray material) produced by the ignition combustion of the fire extinguishing agent 1240 to the flame of the battery cell 10, the partition wall 1250 according to the present embodiment can be superior to the partition wall 1050 according to the above-described embodiment.

[0172] In addition, the concave curved surface 1252 has a maximum width W42 at the top and a minimum width W41 at the bottom with respect to the center line of the fire extinguishing agent 1240. When the concave curved surface 1252 is divided into two parts based on the center line of the fire extinguishing agent 1240, the partition wall 1250 can have a structure of being concavely surrounded from below the fire extinguishing agent 1240 to both sides of the outer side of the fire extinguishing agent 1240.

[0173] Accordingly, the difference between the maximum width W42 and the minimum width W41 of the concave curved surface 1252 can enable the partition wall 1250 to effectively prevent the fire extinguishing agent 1240 from falling toward the battery cell 10.

[0174] Figure 18 is a cross-sectional view of a fire extinguishing agent and a partition wall applied to a battery pack fire extinguisher according to another embodiment of the present disclosure. Referring to Figure 18 , in the battery pack fire extinguisher 104 according to another embodiment, when the partition wall 1350 is divided into two parts based on the center line of the fire extinguishing agent 1340, the partition wall 1350 can have a structure of being concavely surrounded from below the fire extinguishing agent 1340 to one side of the outer side of the fire extinguishing agent 1340.

[0175] Due to the outer wall of the top case 30 (for example, see Figure 2 ), the partition wall can not be provided at a portion of the battery cell 10 where a flame is less likely to occur. For example, the partition wall 1350 is provided only on one side of the outer side of the fire extinguishing agent 1340. Accordingly, compared to the partition wall 1250 according to the above-described embodiment, the partition wall 1350 according to the present embodiment can reduce the required material.

[0176] While the present disclosure has been described in connection with what is presently considered to be the practical embodiments, it is to be understood that the present disclosure is not limited to the disclosed embodiments, instead, the present disclosure is intended to cover various modifications and equivalent arrangements included within the scope of the appended claims and their equivalents.

Claims

1. A battery fire extinguisher comprising: Multiple battery cells; a bottom housing for accommodating the plurality of battery cells; a top case covering the plurality of battery cells and coupled to the bottom case; a fire extinguishing agent between an inner surface of the top housing and an end of at least one of the plurality of battery cells; as well as A partition wall is outside the fire extinguishing agent and protrudes beyond the fire extinguishing agent toward the at least one battery cell among the plurality of battery cells.

2. The battery fire extinguisher according to claim 1, wherein the partition wall is configured to limit the range of inflow of flame into the fire extinguishing agent, and The inflow range excludes flames generated from some battery cells outside the cell group among the plurality of battery cells and guides flames generated from some battery cells within the cell group to the fire extinguishing agent. 3 . The battery fire extinguisher according to claim 1 , wherein the partition wall is a rib of the top case configured to block flames.

4. The battery fire extinguisher according to claim 1, wherein the partition wall comprises plastic resin, stainless steel or aluminum.

5. The battery fire extinguisher according to claim 1, wherein the fire extinguishing agent is formed into a circular plate, and The partition wall is formed into a circular tube corresponding to the outer side of the fire extinguishing agent. 6 . The battery pack fire extinguisher according to claim 5 , wherein the fire extinguishing agent has a through hole in a portion corresponding to the at least one battery cell among the plurality of battery cells.

7. The battery fire extinguisher according to claim 1, wherein the fire extinguishing agent is formed into a quadrilateral plate, and The partition wall is formed into a quadrilateral tube corresponding to the outer side of the fire extinguishing agent.

8. The battery fire extinguisher according to claim 1, wherein the fire extinguishing agent is formed into a hexagonal star-shaped plate, and The partition wall is formed into a hexagonal star-shaped tube corresponding to the outer side of the fire extinguishing agent.

9. The battery fire extinguisher according to claim 1, wherein the fire extinguishing agent is formed into a cross-shaped plate, and The partition wall is formed into a cross-shaped tube corresponding to the outer side of the fire extinguishing agent.

10. The battery fire extinguisher according to claim 1, wherein the fire extinguishing agent is formed into a triangular plate, and The partition wall is formed into a triangular tube corresponding to the outer side of the fire extinguishing agent.

11. The battery fire extinguisher according to claim 1, wherein the fire extinguishing agent has a thickness, and The height of the partition wall is greater than the thickness of the fire extinguishing agent.

12. The battery fire extinguisher according to claim 11, wherein the outer side of the fire extinguishing agent has a side surface perpendicularly intersecting the inner surface of the top case, and The partition wall is inclined at an angle relative to the side surface and has an inclined surface having a minimum width at a top and a maximum width at a bottom relative to a centerline of the fire extinguishing agent. 13 . The battery fire extinguisher according to claim 12 , wherein the partition wall surrounds at least one side of the outer side of the fire extinguishing agent when viewed in a cross-sectional view.

14. The battery fire extinguisher according to claim 12, wherein an upper end of the partition wall and the outer side of the fire extinguishing agent have a gap therebetween.

15. The battery fire extinguisher according to claim 11, wherein the outer side of the fire extinguishing agent has a side surface perpendicularly intersecting the inner surface of the top case, and The partition wall is inclined at an angle relative to the side surface and has an inclined surface having a maximum width at a top and a minimum width at a bottom relative to a center line of the fire extinguishing agent.

16. The battery fire extinguisher according to claim 11, wherein the outer side of the fire extinguishing agent has a side surface perpendicularly intersecting the inner surface of the top case, wherein the partition wall has a vertical surface corresponding to the side surface and a convex curved surface extending from the vertical surface and convex outward, and wherein the convexly curved surface has a minimum width at a top and a maximum width at a bottom relative to a centerline of the fire extinguishing agent. 17 . The battery fire extinguisher according to claim 16 , wherein the convex curved surface convexly surrounds at least one side of the outer side from below the fire extinguishing agent when viewed in a cross-sectional view.

18. The battery fire extinguisher according to claim 11, wherein the outer side of the fire extinguishing agent has a side surface perpendicularly intersecting the inner surface of the top case, wherein the partition wall has a vertical surface corresponding to the side surface and a concave curved surface extending from the vertical surface and concave inwardly, and wherein the concave curved surface has a maximum width at a top and a minimum width at a bottom relative to a centerline of the fire extinguishing agent.

19. The battery fire extinguisher according to claim 18, wherein the concave curved surface concavely surrounds at least one side of the outer side from below the fire extinguishing agent when viewed in a cross-sectional view.

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