Fire extinguishing system for battery of vehicle

Abstract

The present invention relates to a battery fire suppression device for a vehicle, and its main purpose is to provide a battery fire suppression device for a vehicle capable of rapidly detecting and suppressing a fire occurring inside a battery pack and effectively preventing re-ignition caused by overheating of the battery cells after fire suppression. To achieve the above objective, the invention comprises: a circulation pump for supplying and circulating coolant along a coolant line; a battery case that seals and surrounds a battery module in a battery pack; a coolant passage installed inside the battery case to allow coolant supplied through the coolant line to pass through; a fire detection sensor for detecting the occurrence of a fire inside the battery case; and a controller that outputs a control signal for fire suppression when it is determined from the signal of the fire detection sensor that a fire has occurred inside the battery case. A battery fire suppression device for a vehicle is disclosed, comprising a discharge nozzle provided in a coolant passage within the battery case and controlled to discharge coolant from the coolant passage into the interior of the battery case according to a control signal output by the controller, wherein the interior of the battery case is filled with coolant discharged from the discharge nozzle to suppress the fire.

Description

Technology Field

[0001] The present invention relates to a battery fire suppression device for a vehicle, and more specifically, to a battery fire suppression device for a vehicle that can rapidly detect and suppress a fire occurring inside a battery pack and effectively prevent re-ignition caused by overheating of the battery cell after the fire is suppressed. Background Technology

[0003] With the recent increase in interest regarding issues such as energy efficiency, environmental pollution, and the depletion of fossil fuels, the development of eco-friendly vehicles capable of effectively replacing internal combustion engine cars is underway. Eco-friendly vehicles can be broadly classified into pure electric vehicles (BEVs) powered by batteries, hybrid vehicles (HEVs, PHEVs) powered by engines and motors, and fuel cell vehicles (FCEVs) powered by fuel cells and batteries.

[0004] These eco-friendly vehicles (xEVs) are electric vehicles in a broad sense, sharing the common characteristics of being motor-driven vehicles and electrified vehicles that drive by powering a motor with electricity stored in a battery. Such electric vehicles are equipped with a high-voltage battery pack that supplies power to the motor for vehicle propulsion, and the high-voltage battery pack is designed to supply the power required by electrical components within the vehicle, such as the motor, by repeatedly charging and discharging during vehicle operation.

[0005] A battery pack of an electric vehicle is typically composed of a battery case, a battery module placed within the battery case, and a Battery Management System (BMS) that detects the voltage, current, temperature, etc., of the cells constituting the battery module and controls their operation. In addition, the battery pack is configured to prevent fire by blowing a fuse or disconnecting a relay connected to an inverter when an internal short circuit occurs or an overcurrent flows.

[0006] In the case of electric vehicles, fires can occur inside the battery pack during driving due to various causes, such as collisions or component malfunctions. If a fire in the battery pack is not properly extinguished, it can lead to the complete destruction of the vehicle, resulting in significant material and human damage.

[0007] In particular, if a fire occurs inside a battery pack, a fire extinguishing agent must be sprayed onto the affected area to suppress the fire; however, because the structure of the battery case surrounding the battery module makes it difficult for the agent to enter, the fire cannot be effectively extinguished.

[0008] Ultimately, even if a fire in a battery pack is initially extinguished, it may reignite after 2 to 3 hours as adjacent cells overheat. Therefore, to prevent re-ignition, it is necessary to configure a device that can keep the battery cells in a cool state even after the fire has been extinguished. The problem to be solved

[0010] Accordingly, the present invention was created to solve the above-mentioned problems, and aims to provide a vehicle battery fire suppression device that can quickly detect and suppress a fire occurring inside a battery pack and effectively prevent re-ignition caused by overheating of the battery cell after the fire is suppressed.

[0011] The objectives of the present invention are not limited to those mentioned above, and other unmentioned objectives will be clearly understood by those skilled in the art to which the present invention pertains (hereinafter referred to as "skilled in the art") from the description below. means of solving the problem

[0013] To achieve the above objective, according to an embodiment of the present invention, a battery fire suppression device for a vehicle is provided, comprising: a circulation pump for supplying and circulating coolant along a coolant line; a battery case that seals and surrounds a battery module in a battery pack; a coolant passage installed inside the battery case to allow coolant supplied through the coolant line to pass through; a fire detection sensor for detecting the occurrence of a fire inside the battery case; a controller that outputs a control signal for fire suppression when it is determined from the signal of the fire detection sensor that a fire has occurred inside the battery case; and a sprayer provided in the coolant passage inside the battery case and controlled to discharge coolant from the coolant passage into the interior of the battery case according to the control signal output by the controller, wherein the interior of the battery case is filled with coolant discharged from the sprayer for fire suppression. Effects of the invention

[0015] Thus, according to the battery fire suppression device of the present invention, after detecting the occurrence of a fire in a battery pack, the fire can be suppressed in the first place by injecting and filling the battery case of the battery pack where the fire occurred with coolant used for cooling the battery pack, and subsequently, by maintaining the state in which the battery case is filled with coolant, it is possible to effectively prevent re-ignition and thermal runaway from occurring in the battery cells.

[0016] The battery fire suppression device according to the present invention has a configuration integrated with a battery cooling system. In addition to using the cooling water used in the battery cooling system as a fire extinguishing agent, by utilizing a portion of the device configuration of the battery cooling system, it is possible to achieve effective fire suppression and prevention of re-ignition while reducing device costs. Brief explanation of the drawing

[0018] FIG. 1 is a configuration diagram illustrating a battery fire suppression device according to an embodiment of the present invention. FIG. 2 is a block diagram showing the main configuration of a battery fire suppression device according to an embodiment of the present invention. FIGS. 3 to 5 are drawings showing the operating state of a battery fire suppression device according to an embodiment of the present invention. FIG. 6 is a flowchart showing the operating state of a component for fire suppression in a battery fire suppression device according to an embodiment of the present invention. FIG. 7 is a flowchart showing the overall operation process of a battery fire suppression device according to an embodiment of the present invention. Specific details for implementing the invention

[0019] The specific structural or functional descriptions presented in the embodiments of the invention are merely illustrative for the purpose of explaining embodiments according to the concept of the invention, and embodiments according to the concept of the invention may be implemented in various forms. Furthermore, it should not be interpreted as being limited to the embodiments described herein, but should be understood to include all modifications, equivalents, and substitutions that fall within the spirit and scope of the invention.

[0020] Meanwhile, in the present invention, terms such as "first" and / or "second" may be used to describe various components, but said components are not limited to said terms. For the sole purpose of distinguishing one component from other components, for example, without departing from the scope of rights according to the concept of the present invention, the first component may be named the second component, and similarly, the second component may be named the first component.

[0021] When it is stated that one component is "connected" or "connected" to another component, it should be understood that while it may be directly connected or connected to that other component, there may also be other components in between. Conversely, when it is stated that one component is "directly connected" or "directly in contact" with another component, it should be understood that there are no other components in between. Other expressions used to describe the relationship between components, such as "between" and "exactly between," or "adjacent to" and "directly adjacent to," should be interpreted in the same way.

[0022] Throughout the specification, identical reference numbers denote identical components. The terms used in this specification are for describing embodiments and are not intended to limit the invention. In this specification, the singular form includes the plural form unless specifically stated otherwise in the text. As used in this specification, "comprises" and / or "comprising" do not exclude the presence or addition of one or more other components, steps, actions, and / or elements to the mentioned components, steps, actions, and / or elements.

[0024] The present invention aims to provide a vehicle battery fire suppression device capable of rapidly detecting and suppressing a fire that occurs inside a battery pack, and effectively preventing re-ignition caused by overheating of the battery cell after the fire is suppressed.

[0025] Hereinafter, embodiments of the present invention will be described in detail with reference to the attached drawings.

[0026] FIG. 1 is a configuration diagram illustrating a battery fire suppression device according to an embodiment of the present invention, and FIG. 2 is a block diagram showing the main configuration of a battery fire suppression device according to an embodiment of the present invention.

[0027] Referring to FIG. 1, a battery fire suppression device (10) having a configuration integrated with a battery cooling system is illustrated. In the battery fire suppression device (10) according to an embodiment of the present invention, the cooling water of the battery cooling system, that is, the cooling water used to cool the battery pack (20), is used as a fire extinguishing agent. That is, the cooling water of the battery cooling system is normally used as a cooling agent for cooling the battery pack (20), but when a fire occurs, the cooling water is used as a fire extinguishing agent for fire suppression.

[0028] The battery cooling system includes a reservoir tank (11) in which coolant is stored, a circulation pump (13) for pumping coolant for circulation of coolant, a radiator (16) and a cooling fan (17) for dissipating heat from coolant that has cooled the battery pack (20), and a coolant line (12) connecting the reservoir tank (11), the circulation pump (13), the battery pack (20), and the radiator (16) so that the coolant pumped by the circulation pump (13) can circulate through the battery pack (20).

[0029] The above cooling water line (12) includes an inlet-side cooling water line (12a, 12b, 12c) connected to the inlet portion (inlet portion of the cooling water passage) of the battery pack (20) and an outlet-side cooling water line (12d, 12e, 12f) connected to the outlet portion (outlet portion of the cooling water passage) of the battery pack, and the inlet-side cooling water line (12a, 12b, 12c) and the outlet-side cooling water line (12d, 12e, 12f) are connected via a cooling water passage (23) provided inside the battery pack (20).

[0030] Here, the battery pack (20) includes a battery case (21) and a battery module (22) disposed inside the battery case, and the battery module (22) is composed of a plurality of unit cells, i.e., battery cells (22a).

[0031] The battery fire suppression device (10) according to the present invention is configured to suppress a fire that occurs inside a battery pack (20), specifically inside a battery case (21) surrounding a battery module (22) within the battery pack (20).

[0032] To this end, in the battery fire suppression device (10) according to the present invention, when a fire occurs inside the battery case (21), the fire is suppressed by supplying and filling the inside of the battery case (21). In addition, as described below, the cooling state of the battery cell is maintained with the cooling water filled inside the battery case (21) to prevent re-ignition and thermal runaway in the battery cell (22a).

[0033] The battery case (21) of the battery pack (20) is provided with a structure that surrounds the battery module (22) and seals the battery module. Therefore, it is possible to fill the inside of the battery case (21) with cooling water. When cooling water is supplied and filled into the inside of the battery case (21), it is possible to suppress a fire that occurs inside the battery case, as well as to maintain the entire battery cell (22a) and the battery module (22) composed of these battery cells in a cooled state.

[0034] In this way, by filling the interior of the battery case (21) that seals the surroundings of the battery module (22) with cooling water, the entire battery module can be kept in a cooled state by the cooling water even after the fire is extinguished, and consequently, the problem of re-ignition or thermal runaway occurring in the battery cell (22a) due to heat after the fire is extinguished can be reliably prevented.

[0035] In a battery cooling system, a cooling water passage (23) through which cooling water passes is provided inside the battery pack (20) to cool the battery cells (22a) and the battery module (22) composed of these battery cells. Additionally, an inlet cooling water line (12a, 12b, 12c) is connected to the inlet portion, which is one end of the cooling water passage (23) of the battery pack (20), and an outlet cooling water line (12d, 12e, 12f) is connected to the outlet portion, which is the other end of the cooling water passage (23).

[0036] In this way, normally, the coolant in the reservoir tank (11) is pumped by the circulation pump (13) and circulates along the coolant line (12). When the coolant is supplied to the battery pack (20) through the inlet coolant line (12a, 12b, 12c), the supplied coolant flows along the coolant passage (23) inside the battery pack (20), and then is discharged to the outside of the battery pack (20) through the outlet of the coolant passage (23), discharged through the outlet coolant line (12d, 12e, 12f), and then flows back to the radiator (16) and the reservoir tank (11).

[0037] In the interior of the battery pack (20), the cooling water passage (23) may be positioned in a manner that contacts one side of the battery module or surrounds the battery module so that the cooling water can flow around the battery module (22) and cool the battery module. Accordingly, as the cooling water passes through the cooling water passage (23) in the interior of the battery pack (20), the cooling water passes around the battery module (22) and cools the battery module.

[0038] The above-mentioned cooling water passage (23) may be installed inside the battery pack (20) to be in contact with the surface of the battery module (22), and, for example, may be configured by installing a pipe through which cooling water can flow to be in contact with the surface of the battery module (22). At this time, the pipe may be installed on the outer surface of the battery module so as to be in contact with one side of the battery module (22) or to surround the battery module.

[0039] In addition, the cooling water passage (23) can be implemented in various forms by those skilled in the art, provided that the cooling water flowing along the inside is installed in a structure that allows the cooling water to cool the battery module (22) inside the battery case (21). For example, the cooling water passage may be implemented by fixing a pipe through which the cooling water can flow to the inner surface of the battery case (21), or the pipe may be arranged in a spiral or zigzag shape on the surface of the battery module (22).

[0040] Meanwhile, in the battery fire suppression device (10) according to an embodiment of the present invention, a cooling water passage (23) disposed inside the battery pack (20), specifically inside the battery case (21), is provided with a nozzle (24) capable of selectively discharging cooling water into the internal space of the battery case (21). The nozzle (24) may be a valve device or a nozzle device installed in the cooling water passage (23) that is selectively opened to enable external discharge and ejection of cooling water within the cooling water passage.

[0041] The above-mentioned nozzle (24) can be installed at the upstream position (upstream position) in the cooling water passage (23) inside the battery case (21), and is configured so that its opening and closing operation can be controlled according to an external electrical signal, that is, a control signal output by the controller (30). Consequently, when the nozzle (24) is opened by the controller (30), the cooling water flowing into the cooling water passage (23) is discharged into the interior of the battery case (21), and the interior of the battery case (21) is filled with cooling water to form a water tank.

[0042] In this way, a fire that occurs inside the battery pack (20) can be initially suppressed by the cooling water released into the battery case (21), and after the cooling water is filled into the battery case (21) like a water tank, the cooling state of the battery cell (22a) can be continuously maintained by the cooling water.

[0043] The greatest risk of a fire occurring in a battery is re-ignition, and even if the fire appears to have been completely extinguished, the adjacent battery cell (22a) may overheat and the fire may re-ignite after 1 to 2 hours. However, as in the present invention, if the battery cell (22a) is left in the cooling water by filling the inside of the battery case (21) with cooling water like a water tank, the battery cell (22a) can be continuously cooled because the cooling water (liquid) has a high heat transfer rate, and re-ignition and thermal runaway in the battery cell (22a) after the initial fire suppression can be effectively prevented.

[0044] A battery fire suppression device (10) according to an embodiment of the present invention may further include a fire detection sensor (25) that detects the occurrence of a fire in a battery pack (20), and the fire detection sensor (25) may be installed on one side of the discharge device (24) inside the battery case (21) or on the inner surface of the battery case around it. In an embodiment of the present invention, the fire detection sensor (25) may be a gas detection sensor that detects gas generated when the battery separator decomposes upon the occurrence of a fire.

[0045] The fire detection sensor (25) is connected to a controller (30) and configured to input a signal indicating fire detection to the controller (30). Accordingly, the controller (30) can recognize that a fire has occurred inside the battery pack (20) from the signal of the fire detection sensor (25). For example, the controller (30) can determine that a fire has occurred inside the battery pack (20) if the concentration of gas detected by the fire detection sensor (25) is greater than or equal to a predetermined set value.

[0046] Additionally, the battery fire suppression device (10) according to an embodiment of the present invention may further include a temperature sensor (26) for detecting the temperature of a battery cell (22a) in a battery pack (20). The temperature sensor (26) is connected to a controller (30) and configured to input a signal according to the temperature of the battery cell (22a) to the controller (30).

[0047] Accordingly, the controller (30) can detect the temperature of the battery cell (22a) in real time from the signal of the temperature sensor (26). The temperature of the battery cell (22a) detected by the temperature sensor (26) in the controller (30) can be used to monitor whether re-ignition and thermal runaway occur in the battery cell. For example, if the temperature of the battery cell (22a) detected by the temperature sensor (26) exceeds a predetermined set temperature, the controller (30) can determine that re-ignition or thermal runaway has occurred in the battery cell (22a) within the battery pack (20).

[0048] In this manner, in an embodiment of the present invention, the controller (30) supplies cooling water to the interior of the battery pack (20) where the fire occurred to suppress the fire, and then continuously monitors whether re-ignition or thermal runaway occurs in the battery cell (22a) based on the temperature of the battery cell (22a) detected by the temperature sensor (26).

[0049] In addition, in an embodiment of the present invention, if it is determined that a fire has occurred inside the battery pack (20) or that a re-ignition or thermal runaway has occurred in the battery cell (22a) as described above, the controller (30) can display information related to the fire, re-ignition, or thermal runaway in real time through the vehicle's information providing device (40) at the time of determination or warn the driver.

[0050] Here, the information providing device (40) may be a warning device within the vehicle, and the warning device may be a warning light of the cluster. Alternatively, the information providing device (40) may be a display device capable of displaying relevant information or a sound output device capable of outputting a sound such as a warning sound.

[0051] Meanwhile, a shut-off valve (15) capable of selectively blocking the flow of cooling water may be installed in the outlet cooling water lines (12d, 12e, 12f). The shut-off valve (15) is controlled to open and close according to a control signal output by a controller (30), and closes the flow path of the outlet cooling water lines (12d, 12e, 12f) connected to the battery pack (20) according to a control signal output by the controller (30) that detects the occurrence of a fire.

[0052] In an embodiment of the present invention, when the controller (30) detects a fire inside the battery pack (20), it opens the discharge nozzle (24) and simultaneously closes the shut-off valve (15) so that the flow path of the outlet-side cooling water lines (12d, 12e, 12f) is blocked by the shut-off valve (15). Accordingly, in the event of a fire, the cooling water is not discharged from the cooling water passage (23) inside the battery pack (20) to the outlet-side cooling water lines (12d, 12e, 12f). In this way, with the flow path of the outlet-side cooling water lines (12d, 12e, 12f) blocked, the cooling water in the cooling water passage (23) is discharged into the interior of the battery case (21) through the discharge nozzle (24).

[0053] In addition, in the battery fire suppression device (10) according to an embodiment of the present invention, after monitoring whether a fire has occurred in each of the plurality of battery packs (20), the fire can be suppressed by supplying cooling water only to the battery pack (20) where a fire has occurred. However, in normal times when no fire has occurred, cooling water is supplied to pass through all of the plurality of battery packs (20), and the battery pack (20) is cooled to a temperature below a predetermined temperature while the cooling water supplied to each battery pack (20) passes through the cooling water passage (23).

[0054] In order to selectively supply cooling water to a plurality of battery packs (20) as described above, a flow control valve (14) is installed in the cooling water line (12) through which cooling water is supplied from the circulation pump (13) to each battery pack (20). That is, as shown in FIG. 1, the inlet cooling water lines (12a, 12b, 12c) are branched according to the number of battery packs (20) and connected to the corresponding battery packs (20) so that the cooling water sent by the circulation pump (13) can be distributed and flow to each battery pack (20).

[0055] At this time, the branched inlet-side cooling water lines (12a, 12b, 12c) are connected to the inlet of the cooling water passage (23) within the battery pack (20). As a result, the cooling water pressurized by the circulation pump (13) is distributed from the cooling water line (12) to each inlet-side cooling water line (12a, 12b, 12c) and flows through the cooling water passage (23) within each battery pack (20).

[0056] In addition, a flow control valve (14) is installed at the branching point where the inlet cooling water lines (12a, 12b, 12c) are branched, so that cooling water can be selectively supplied to each battery pack (20). The flow control valve (14) is controlled by a controller (30) to selectively open and close the flow paths of the branched inlet cooling water lines (12a, 12b, 12c).

[0057] FIG. 1 illustrates an example in which cooling and fire suppression can be performed on three battery packs (20), wherein the number of battery packs (20) and the number of flow control valves (14) can be varied.

[0058] For example, instead of three, two or four battery packs (20) may be connected through each inlet-side cooling water line to receive cooling water, and when two battery packs (20) are applied, the flow control valve (14) may be a 3-way valve. If four battery packs (20) are applied, the flow control valve (14) may be a 5-way valve, and if three battery packs (20) are applied as in FIG. 1, the flow control valve (14) may be a 4-way valve.

[0059] Additionally, six battery packs (20) may be applied, in which case the coolant line (12) is first branched into two, and then each branched coolant line is further branched into three, and a 4-way valve may be installed as the flow control valve (14) at each branch of the three branched coolant lines, in which case a total of two flow control valves (14) are used.

[0060] Additionally, five battery packs (20) may be applied, in which case the cooling water line (12) is branched into two, and one of the two branched cooling water lines may be branched into two inlet cooling water lines and the other into three inlet cooling water lines, and it is possible to install a 3-way valve and a 4-way valve, respectively, as flow control valves (14) at each branch of the inlet cooling water line.

[0061] In this way, the number of battery packs (20) subject to cooling and fire suppression, the number of installed flow control valves (14), and the number of branched cooling water lines (12) can be appropriately adjusted as needed and various changes are possible.

[0062] The above flow control valve (14) is controlled in an operating state by a controller (30), and may be controlled to supply cooling water to all battery packs (20) according to a control signal output by the controller (30), or may be controlled to supply cooling water only to selected battery packs (20) according to a control signal output by the controller (30). Of course, the flow control valve (14) is controlled to open the flow path of the inlet cooling water lines (12a, 12b, 12c) connected to the battery packs (20) to which cooling water is to be supplied.

[0063] In a battery fire suppression device (10) according to an embodiment of the present invention, a controller (30) receives a signal from a fire detection sensor (25), identifies the battery pack (20) where a fire has occurred among all battery packs (20), and controls the opening state and operating state of a flow control valve (14) so ​​that the cooling water pressurized by the circulation pump (13) can be supplied only to the battery pack (20) where a fire has been detected among all battery packs (20).

[0064] Additionally, in an embodiment for multiple battery packs (20), the outlet-side coolant lines (12d, 12e, 12f) connected to the outlet portion of the coolant passage (23) within each battery pack (20) are combined into a single coolant line (12), and the combined coolant line (12) is connected to a reservoir tank (11) via a radiator (16).

[0065] At this time, the shut-off valve (15) may be installed in the confluence section where the outlet-side cooling water lines (12d, 12e, 12f) are combined. The shut-off valve (15) is controlled by a controller (30) to selectively open and close the flow path of the outlet-side cooling water lines (17d, 17e, 17f) that are combined. The controller (30) controls the opening state of the shut-off valve (15) so as to close only the flow path of the outlet-side cooling water lines (17d, 17e, 17f) connected to the outlet section of the cooling water passage (23) of the battery pack (20) where the fire occurred.

[0066] And, normally, cooling water circulates through a path passing through a cooling water passage (23) inside a battery case (21) to cool the battery pack (20), but in the event of a fire, the nozzle (24) is opened and a large amount of cooling water is discharged from the cooling water passage (23) into the interior of the battery case (21) through the nozzle.

[0067] Therefore, normally, only the cooling water stored in the reservoir tank (11) is circulated and used through the circulation pump (13) to cool the battery pack (20), but in the event of a fire, a larger amount of cooling water must be supplied to the battery pack (20) where the fire occurred through the circulation pump (13).

[0068] Accordingly, the battery fire suppression device (10) according to an embodiment of the present invention may be configured to further include a sub-tank (1), which is a separate cooling water storage tank, so that cooling water can be additionally replenished and used only when a fire occurs. The sub-tank (1) is a tank in which cooling water to be used only when a fire occurs is stored, and is connected to the main tank, the reservoir tank (11), through a replenishment line (2). In addition, a replenishment valve (3), whose opening and closing operation is controlled by a controller (30), is installed in the replenishment line (2).

[0069] Ultimately, when the controller (30) detects a fire through the fire detection sensor (25), it opens the replenishment valve (3) so that the cooling water in the sub-tank (1) can be sucked in and replenished into the main tank, the reservoir tank (11), through the replenishment line (2) by the suction force of the circulation pump (13).

[0070] In FIG. 1, the size of the reservoir tank (11) and the sub-tank (1) is shown as being smaller than the internal volume of the battery pack (20) (the internal volume of the battery case), but this is merely a schematic illustration to help understand the present invention regarding the component configuration and connection relationships, etc., and the size of the reservoir tank (11) and the sub-tank (1) can be set so that a sufficient amount of cooling water can be supplied to fill the inside of the battery case (21) even if a fire occurs in the entire battery pack (20).

[0071] In addition, a separate extinguishing agent can be stored mixed with cooling water in the sub-tank (1), and a extinguishing agent mixed with potassium carbonate, water, and a surfactant can be additionally mixed with the cooling water in the sub-tank (1) and stored.

[0072] When the controller (30) detects a fire and opens the replenishment valve (3), the suction force of the circulation pump (13) acts on the sub-tank (1) through the reservoir tank (11). At this time, the mixture of cooling water and fire extinguishing liquid in the sub-tank (1) is sucked into the reservoir tank (11), mixed with the cooling water stored in the reservoir tank (11), and then supplied to the battery pack (20) where the fire occurred through the cooling water line (12).

[0073] FIGS. 3 to 5 are drawings illustrating the operating state of a battery fire suppression device (10) according to an embodiment of the present invention. FIG. 3 illustrates the operating state when a fire occurs only in battery pack 1 (20), FIG. 4 illustrates the operating state when a fire occurs in battery packs 1 and 2 (20). FIG. 5 illustrates the operating state when a fire occurs in all three battery packs (20).

[0074] In FIGS. 3 to 5, the arrow '→' in the cooling water lines (12, 12a, 12b, 12c) and the sprayer (24) indicates the flow and discharge state of the cooling water supplied to and injected into the battery pack (20), and 'X' indicates that the cooling water is blocked from flowing.

[0075] As described, the flow control valve (14) at the upstream (upstream) position (inlet side cooling water line position) of the battery pack (20) is controlled so that cooling water can be supplied and injected into the interior of the battery case (21) only for the battery pack (20) where the fire occurred.

[0076] In addition, the shut-off valve (15) at the downstream (downstream) position (outlet side cooling water line position) of the battery pack (20) is controlled to be closed so that the cooling water filled inside the battery case (21) is not discharged to the outside and remains filled only for the battery pack (20) where the fire occurred.

[0077] FIG. 6 is a flowchart showing the operating state of a component for fire suppression in a battery fire suppression device according to an embodiment of the present invention, and FIG. 7 is a flowchart showing the overall operation process of a battery fire suppression device according to an embodiment of the present invention.

[0078] First, regarding FIG. 6, when a fire in the battery pack (20) is detected (S1), the battery power supply is cut off and the drive motor cannot operate, so driving the vehicle becomes impossible (S2). At this time, the controller (30) activates the information providing device (warning device) (40) to warn of the occurrence of a fire, thereby allowing the driver and passengers to evacuate from the vehicle (S3).

[0079] Additionally, cooling water is supplied only to the battery pack (20) where the fire occurred, and the fire inside the battery pack is extinguished by the cooling water filled inside the battery case (21). That is, the replenishment valve (3) is opened, the operation of the circulation pump (13) is started or maintained, and the discharge port (24) of the battery pack (20) where the fire occurred is controlled to open only the discharge port (S4).

[0080] In addition, the opening and operating state of the flow control valve (14) is controlled so that coolant is supplied only to the battery pack (20) where the fire occurred, and at the same time, the shut-off valve (15) is closed so that the coolant filled inside the battery pack (20) where the fire occurred is not discharged to the outside through the outlet side coolant lines (12d, 12e, 12f) (S4).

[0081] If a fire occurs in two battery packs (20), the opening state and operating state of the flow control valve (14) are controlled so that coolant is supplied only to the two battery packs (20) where the fire occurred, and if a fire occurs in all three battery packs (20), the opening state and operating state of the flow control valve (14) are controlled so that coolant is supplied to all three battery packs (20).

[0082] That is, if a fire occurs in all three battery packs (20), the opening state of the flow control valve (14) is controlled to open all the flow paths of each inlet-side cooling water line (12a, 12b, 12c) branched and connected to each battery pack (20). If a fire occurs in two battery packs (20), the opening state of the flow control valve (14) is controlled to open only the flow paths of the two inlet-side cooling water lines connected to the battery pack (20) where the fire occurred, and close the flow path of the remaining one inlet-side cooling water line.

[0083] In addition, in the case of the shut-off valve (15), the operation of the shut-off valve is controlled so that only the flow paths of the outlet-side cooling water lines (12d, 12e, 12f) connected to the battery pack (20) where the fire occurred are closed. For example, if the fire occurred in all three battery packs (20), the operation of the shut-off valve (15) is controlled so that all the flow paths of the outlet-side cooling water lines (12d, 12e, 12f) connected to each battery pack (20) are closed simultaneously, and if the fire occurred in only two battery packs (20), the operation of the shut-off valve (15) is controlled so that only the flow paths of the two outlet-side cooling water lines (12d, 12e, 12f) connected to the battery pack (20) where the fire occurred are closed.

[0084] Once the first fire suppression is completed as described above, the controller (30) continues to monitor whether re-ignition and thermal runaway occur in the battery cell (22a) within the battery pack (20) where the fire was suppressed, based on the temperature of the battery cell detected by the temperature sensor (26) while the inside of the battery case (21) is filled with cooling water (S5).

[0085] Under normal conditions when no fire occurs in the battery pack (20), the controller (30) controls the opening and operating state of the flow control valve (14) so ​​that the inlet cooling water lines (12a, 12b, 12c) connected to each battery pack (20) are all opened, so that cooling water can be distributed to all battery packs (20) for cooling the battery pack (20). Additionally, under normal conditions, the controller controls the opening and operating state of the shut-off valve (15) so that the cooling water passing through each battery pack (20) is discharged to the outlet cooling water lines (12d, 12e, 12f) and then continues to circulate along the cooling water line (12) passing through the radiator (16), so that the outlet cooling water lines (12d, 12e, 12f) connected to all battery packs (20) are all opened.

[0086] Meanwhile, referring to FIG. 7, the overall process is explained again. When the vehicle is in the key-on state (S11), the controller (30) determines that a fire has occurred if gas with a concentration (Z(N)) greater than a set value is detected inside a specific battery pack (20) through the fire detection sensor (25) (S12, S13). The controller (30) can monitor whether a fire has occurred inside the battery pack (20) from the signal of the fire detection sensor (25).

[0087] Additionally, if the controller (30) determines that a fire has occurred inside part or all of the battery pack (20), it warns of the fire (S14), checks the battery pack (20) where the fire occurred (S15), and outputs a control signal to suppress the fire.

[0088] At this time, the opening state of the flow control valve (14) installed in the inlet cooling water line (12a, 12b, 12c) is controlled according to the control signal output by the controller (30) so that cooling water can be supplied only to the battery pack (20) where the fire occurred. In addition, the shut-off valve (15) installed in the outlet cooling water line (12d, 12e, 12f) is controlled to close, and the ejector (24) inside the battery pack (20) where the fire occurred is controlled to open the ejection port.

[0089] Thus, the cooling water, which is pressurized by the circulation pump (13) from the reservoir tank (11) and sub-tank (1) along the inlet cooling water lines (12a, 12b, 12c), is discharged from the discharger (24) of the battery pack (20) where the fire occurred, and consequently, the inside of the battery case (21) of the battery pack (20) where the fire occurred is filled with cooling water discharged through the discharger (24).

[0090] Accordingly, the fire that occurred in the battery pack (20) can be extinguished (S16), and since the inside of the battery case (21) is continuously filled with cooling water like a water tank, the fire can be prevented from reigniting as the temperature of the battery cell (22a) rises.

[0091] When a fire is extinguished, the extinguishing agent mixed with the cooling water inside the sub-tank (1) can be supplied to the battery pack (20) together with the cooling water in the reservoir tank (11), and the cooling water mixed with the extinguishing agent at a certain ratio can be supplied to the inside of the battery case (21) so that the fire can be effectively extinguished, and furthermore, as the cooling water is continuously filled inside the battery case (21), re-ignition in the battery cell (22a) can be reliably prevented.

[0092] And, even after the fire is extinguished, the controller (30) monitors whether re-ignition and thermal runaway occur in the battery cell (22a) from the temperature of the battery cell detected by the temperature sensor (26) inside the battery pack (20) where the fire occurred (S17).

[0093] At this time, it is checked whether the temperature of the battery cell (22a) exceeds the set temperature. If the temperature of the battery cell exceeds the set temperature, the controller (30) determines that a re-ignition or thermal runaway has occurred in the battery cell and activates the information providing device (40) to output related information.

[0094] In this way, the configuration and operating state of the battery fire suppression device for a vehicle according to an embodiment of the present invention have been described in detail. As described above, according to the battery fire suppression device for a vehicle according to an embodiment of the present invention, a fire occurring inside a battery pack can be quickly detected and suppressed, and re-ignition and thermal runaway that may occur due to overheating of the battery cell after the fire is suppressed can be effectively prevented.

[0095] In particular, the battery fire suppression device according to the present invention has a configuration integrated with a battery cooling system. By utilizing the cooling water used in the battery cooling system as a fire extinguishing agent and by utilizing a portion of the device configuration of the battery cooling system, it is possible to achieve effective fire suppression and prevention of re-ignition while reducing device costs.

[0097] Although 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 by those skilled in the art using the basic concept of the present invention as defined in the following claims are also included within the scope of the present invention. Explanation of the symbols

[0099] 1 : Sub tank 2 : Replenishment line 3: Replenishment valve 10: Battery fire suppression device 11: Reservoir tank 12: Coolant line 12a, 12b, 12c: Inlet coolant lines 12d, 12e, 12f: Outlet coolant lines 13: Circulation pump 14: Flow control valve 15: Shut-off valve 16: Radiator 17 : Cooling fan 20 : Battery pack 21 : Battery case 22 : Battery module 22a: Battery cell 23: Coolant passage 24 : Discharger 25 : Fire detection sensor 26 : Temperature sensor 30 : Controller 40 : Information providing device

Claims

Claim 1 A circulation pump for supplying and circulating coolant along a coolant line; a battery case that seals and surrounds a battery module in a battery pack; a coolant passage installed inside the battery case to allow coolant supplied through the coolant line to pass through; a fire detection sensor for detecting the occurrence of a fire inside the battery case; and a controller that outputs a control signal for fire suppression when it is determined from the signal of the fire detection sensor that a fire has occurred inside the battery case. A battery fire suppression device for a vehicle, comprising: a discharge nozzle provided in a coolant passage within the battery case and controlled to discharge coolant from the coolant passage into the interior of the battery case according to a control signal output by the controller; configured such that the interior of the battery case is filled with coolant discharged from the discharge nozzle for fire suppression; wherein a plurality of battery packs, each equipped with the battery case, battery module, coolant passage, fire detection sensor, and discharge nozzle, are installed in a vehicle, wherein a coolant line supplied with coolant pressurized by the circulation pump is branched and connected to the inlet of the coolant passage of each battery pack, and a flow control valve is installed at the branch portion where the coolant line is branched, which is controlled by the controller to selectively open and close the flow path of the branched coolant line, and wherein the controller controls the opening state of the flow control valve so that coolant is supplied through the branched coolant line only to the battery pack among the plurality of battery packs that is determined to have a fire by the fire detection sensor. Claim 2 A battery fire suppression device for a vehicle according to claim 1, further comprising a reservoir tank in which coolant for cooling the battery pack is stored, and wherein the outlet of the coolant passage of the battery pack is connected to the reservoir tank through a coolant line. Claim 3 A battery fire suppression device for a vehicle according to claim 2, characterized in that a radiator is installed in a coolant line connected to the outlet of the coolant passage, and when no fire occurs in the battery pack, the coolant stored in the reservoir tank is circulated by a circulation pump through the coolant passage of the battery pack and the radiator to cool the battery pack. Claim 4 A battery fire suppression device for a vehicle according to claim 2, further comprising a shut-off valve installed in a cooling water line connected to the cooling water passage outlet and closed according to a control signal output by a controller in the event of a fire, wherein the interior of the battery case is filled with cooling water when the shut-off valve is closed. Claim 5 A battery fire suppression device for a vehicle according to claim 2, further comprising: a sub-tank in which the coolant is stored separately; a replenishment line connecting the sub-tank and the reservoir tank; and a replenishment valve installed in the replenishment line that operates to open according to a control signal output by a controller in the event of a fire, wherein the coolant in the sub-tank sucked in by a circulation pump while the replenishment valve is open is supplied to the battery pack where the fire has occurred together with the coolant in the reservoir tank. Claim 6 A vehicle battery fire suppression device according to claim 5, characterized in that coolant and fire extinguishing liquid are stored in a mixed state within the sub-tank. Claim 7 A battery fire suppression device for a vehicle according to claim 1, further comprising a temperature sensor installed inside the battery case to detect the temperature of a battery cell and input a signal according to the detected temperature to a controller. Claim 8 A battery fire suppression device for a vehicle according to claim 7, wherein the controller determines that re-ignition or thermal runaway has occurred in the battery cell when the temperature of the battery cell detected by the temperature sensor exceeds a set temperature while the battery case is filled with coolant after fire suppression, and provides information regarding re-ignition or thermal runaway through the vehicle's information providing device. Claim 9 A battery fire suppression device for a vehicle according to claim 8, wherein the information providing device is a warning device that operates to visually or audibly warn of re-ignition or thermal runaway in a battery cell. Claim 10 delete Claim 11 delete Claim 12 A battery fire suppression device for a vehicle according to claim 1, characterized in that the outlet-side coolant lines connected to the outlet portion of the coolant passage of each battery pack are combined into a single coolant line, and a shut-off valve is installed in the combining portion where the outlet-side coolant lines are combined, the shut-off valve being controlled by the controller to selectively open and close the flow path of the combined outlet-side coolant lines. Claim 13 A battery fire suppression device for a vehicle according to claim 12, wherein the controller controls the opening state of the shut-off valve to close only the flow path of the coolant in the outlet-side coolant line connected to the coolant passage outlet of the battery pack determined by the fire detection sensor to have a fire among the plurality of battery packs.

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