A PACK level gas-liquid fire extinguishing device and battery pack

Abstract

The utility model discloses a PACK level gas liquid fire extinguishing device and battery package, gas fire extinguishing unit is connected through the end of thermosensitive wire electric ignition head of perfluorocyclohexanone fire extinguishing device, the input section of multistage pipeline of liquid fire extinguishing unit sets up solenoid valve group, and forms liquid fire control interface that links to each other liquid cooling system outward, solenoid valve group contains the first solenoid valve and second solenoid valve of series connection setting, and the multistage pipeline between first solenoid valve and second solenoid valve is equipped with liquid level sensor, the feedback signal wire harness of perfluorocyclohexanone fire extinguishing device, the control signal wire harness of first solenoid valve and second solenoid valve, the acquisition signal wire harness of liquid level sensor all access solenoid valve control module. The device cancels PACK level temperature / smoke detector, and the fire source is accurately positioned through thermosensitive wire, and the branch adopts fire detection tube directional blasting delivery fire control liquid, and gas liquid double fire extinguishing mechanism promotes response speed, and inhibits the rekindling, and only needs to replace the fault battery package, and the maintenance cost is low.

Description

Technical Field

[0001] This utility model relates to fire extinguishing devices, and more particularly to a PACK-level gas-liquid fire extinguishing device and a battery pack. Background Technology

[0002] In recent years, my country's new energy storage technologies have developed rapidly and have achieved large-scale commercial applications. Energy storage applications are becoming increasingly widespread, covering various power scenarios such as the power source side, grid side, user side, and distributed microgrids. This diversity of applications has driven the diversified development of energy storage technologies, with electrochemical energy storage technologies, represented by lithium-ion batteries, sodium-ion batteries, and flow batteries, playing a dominant role.

[0003] The main causes of lithium battery fires include overcharging, over-discharging, internal or external short circuits, and mechanical compression. These factors can easily lead to violent exothermic reactions between the positive and negative electrodes and the electrolyte inside the battery, which can then cause thermal runaway and eventually escalate into a fire or even an explosion.

[0004] For fires caused by battery thermal runaway, current mainstream fire suppression solutions mainly include gas-based and water-based methods. Gas-based fire suppression (such as heptafluoropropane and perfluorohexanone) typically uses storage tanks to store the extinguishing agent. When a fire occurs, the system receives a trigger signal and releases the extinguishing agent, flooding the entire energy storage compartment. The fire is extinguished by asphyxiation or chemical suppression when the extinguishing agent reaches a certain concentration. A significant drawback of this method is its inability to accurately locate the fire source (the initiation point of thermal runaway), making it difficult to quickly and accurately suppress the source battery pack in the early stages of the fire (initial thermal runaway), resulting in a delayed response and low extinguishing efficiency. Water-based fire suppression relies on external fire hydrants or fixed fire suppression systems. During a fire, fire valves are opened, and fire water is sprayed through pre-installed pipes and nozzles within the compartment to cover the fire. The shortcomings of this solution are: the fire extinguishing effect is highly dependent on the density and rationality of the nozzle arrangement; the water flow is difficult to penetrate the battery pack shell quickly and accurately to act on the internal thermal runaway cells; water spray may cause the battery short circuit range to expand or trigger a violent reaction of the electrolyte; and it has the disadvantages of slow response speed and inability to effectively prevent reignition. Utility Model Content

[0005] To address the shortcomings of the aforementioned technologies, this invention provides a PACK-level gas-liquid fire extinguishing device and a battery pack.

[0006] To solve the above technical problems, the technical solution adopted by this utility model is: a PACK-level gas-liquid fire extinguishing device, including a gas fire extinguishing unit and a liquid fire extinguishing unit;

[0007] The gas extinguishing unit includes a prefabricated perfluorohexanone extinguishing device and a thermal wire attached to the battery module. The end of the thermal wire is connected to the electric ignition head of the perfluorohexanone extinguishing device.

[0008] The liquid fire extinguishing unit includes a multi-stage pipeline that runs around the battery pack and is connected by a fire detection tube. The input section of the multi-stage pipeline is equipped with a solenoid valve group and forms a liquid fire extinguishing interface that connects to the liquid cooling system. The solenoid valve group includes a first solenoid valve and a second solenoid valve arranged in series. A liquid level sensor is installed in the multi-stage pipeline located between the first solenoid valve and the second solenoid valve.

[0009] The feedback signal harness of the perfluorohexanone fire extinguishing device, the control signal harness of the first and second solenoid valves, and the acquisition signal harness of the liquid level sensor are all connected to the solenoid valve control module.

[0010] Furthermore, the multi-stage pipeline includes a primary pipeline, a secondary pipeline, and a tertiary pipeline. The primary pipeline is equipped with a first solenoid valve and a second solenoid valve. The secondary pipeline branches off from the primary pipeline and extends towards each battery cluster. The tertiary pipeline branches off from the secondary pipeline and extends towards each battery pack.

[0011] Furthermore, the first solenoid valve is located near the liquid fire-fighting interface, and the second solenoid valve is a one-way solenoid valve that controls the flow of fire-fighting liquid from the primary pipeline to the secondary pipeline.

[0012] Furthermore, the tertiary piping is located directly above each battery pack.

[0013] A battery pack includes a PACK-level gas-liquid fire extinguishing device, wherein the upper cover of the battery module is provided with a pressure relief valve for thermal runaway relief and auxiliary fire-fighting fluid injection.

[0014] This invention provides a PACK-level gas-liquid fire extinguishing device and battery pack. By using thermally sensitive wires for physical positioning and fire detection tubes for directional blasting, it solves the problem of traditional whole-cabin fire extinguishing systems being unable to accurately locate the fire source, achieving a second-level response during the incipient stage of thermal runaway. It adopts a two-stage gas-liquid fire extinguishing system—perfluorohexanone for rapid asphyxiation of open flames combined with fire-fighting liquid immersion cooling—overcoming the shortcomings of water fire extinguishing systems, such as difficulty in penetrating the battery pack and easy reignition. At the same time, it eliminates electronic detectors and simplifies branch valves, significantly reducing maintenance costs, and only requires replacement of the faulty battery pack, avoiding the loss of the entire cabin. Attached Figure Description

[0015] Figure 1 This is a schematic diagram of the entire package.

[0016] Figure 2 This is a schematic diagram of the internal structure of the battery pack.

[0017] Figure 3 This is a schematic diagram of a multi-stage pipeline system.

[0018] In the diagram: 101, thermal wire; 102, perfluorohexanone fire extinguishing device; 201, multi-stage pipeline; 202, liquid fire extinguishing interface; 203, first solenoid valve; 204, second solenoid valve; 205, liquid level sensor; 300, pressure relief valve; 201a, primary pipeline; 201b, secondary pipeline; 201c, tertiary pipeline; 400, battery module. Detailed Implementation

[0019] The present invention will now be described in further detail with reference to the accompanying drawings and specific embodiments.

[0020] Example 1;

[0021] Figure 2 and 3 The device shown is a PACK-level gas-liquid fire extinguishing system, comprising a gas extinguishing unit and a liquid extinguishing unit. The gas extinguishing unit rapidly suppresses open flames and interrupts the combustion chain reaction after thermal runaway occurs; the liquid extinguishing unit completely eliminates residual heat after gas extinguishing to prevent reignition.

[0022] Specifically, the gas extinguishing unit includes a prefabricated perfluorohexanone extinguishing device 102 and a thermally sensitive wire 101 attached to the battery module 400. The end of the thermally sensitive wire 101 is connected to the electric ignition head of the perfluorohexanone extinguishing device 102. The perfluorohexanone extinguishing device is physically triggered by the spontaneous combustion of the thermally sensitive wire attached to the battery module 400. After the thermally sensitive wire spontaneously combusts, it directly ignites the electric ignition head inside the perfluorohexanone device, triggering the pressurized spray of the extinguishing agent. The electric ignition head detonates the gas-generating agent inside the device, instantly generating high-pressure gas. This high-pressure gas propels the perfluorohexanone agent through the sealing membrane and sprays it directionally towards the fire source. It should be understood that the perfluorohexanone extinguishing device is a commercially available product.

[0023] The liquid fire extinguishing unit includes a multi-stage pipeline 201 that runs around the battery pack and is connected by fire detection tubes. The input section of the multi-stage pipeline 201 is equipped with a solenoid valve group and forms a liquid fire extinguishing interface 202 that connects to the liquid cooling system. Specifically, the multi-stage pipeline 201 includes a primary pipeline 201a, a secondary pipeline 201b, and a tertiary pipeline 201c. The primary pipeline 201a is equipped with a first solenoid valve 203 and a second solenoid valve 204. The secondary pipeline 201b branches from the primary pipeline 201a and extends towards each battery cluster. The tertiary pipeline 201c branches from the secondary pipeline 201b and extends towards each battery pack. The three-stage pipeline 201c is located directly above each battery pack. This way, if the fire detection tube bursts due to heat, only the faulty battery pack's fire-fighting fluid passage is opened, allowing the fire-fighting fluid (such as flame-retardant coolant) to directly immerse the battery cell and continuously absorb heat until thermal equilibrium is reached. The solenoid valve assembly includes a first solenoid valve 203 and a second solenoid valve 204 connected in series. A liquid level sensor 205 is installed in the multi-stage pipeline 201 located between the first solenoid valve 203 and the second solenoid valve 204. The first solenoid valve 203 is positioned near the liquid fire-fighting interface 202. The main control path is controlled by solenoid valve 203. The second solenoid valve 203 is a one-way solenoid valve controlling the flow of fire-fighting liquid from primary pipeline 201a to secondary pipeline 201b. The second solenoid valve 204 is a one-way valve to prevent liquid backflow and contamination of the liquid cooling system. Liquid level sensor 205 monitors inter-valve leakage in real time and issues an alarm. The feedback signal harness of the perfluorohexanone fire extinguishing device 102, the control signal harnesses of the first and second solenoid valves 203 and 204, and the acquisition signal harness of the liquid level sensor 205 are all connected to the solenoid valve control module. The solenoid valve control module uses an STM32F407 MCU as its core. It acquires the 4-20mA current signal from the liquid level sensor through the AI ​​channel and receives the 24V switching feedback signal from the perfluorohexanone device through the DI channel. After parsing the signal, the MCU outputs a 24V pulse (500ms) through the DO channel to drive the first and second solenoid valves 203 and 204, and communicates with the BMS via a CAN bus (500kbps). The power supply layer reduces the external DC 48V input to 24V (valve power supply) via a Buck circuit, and then outputs 5V (MCU power supply) via an LDO regulator. The drive layer uses a PC817 optocoupler to isolate the MCU signal, and the valve coil is controlled by an IRF540N MOSFET, with a parallel freewheeling diode to eliminate back EMF. The overall design ensures reliable operation in strong electromagnetic environments through current loop immunity (AI), optocoupler isolation (DI / DO), and TVS protection (CAN). Of course, it is not limited to the above form; theoretically, any application that can realize the identification of feedback and sensor signals, as well as the control of the first solenoid valve 203 and the second solenoid valve 204, can be applied to this patent.

[0024] Therefore, when the battery experiences thermal runaway or fire, the thermally sensitive wire spontaneously combusts and triggers the perfluorohexanone (PFH) extinguishing device. The device rapidly generates a large amount of gas, releasing the extinguishing agent. The agent quickly vaporizes, absorbing the heat generated by the battery, rapidly reducing the cell temperature, isolating oxygen, and providing chemical inhibition, thus effectively extinguishing open flames and suppressing the fire. After the PPHH extinguishing device is activated, it sends a spray signal to the solenoid valve control module via a feedback harness. Simultaneously, the fire detection tube softens and bursts due to heat, preparing for the immersion of fire-fighting fluid. When the solenoid valve control module receives the PPHH spray signal feedback, it controls the first and second solenoid valves to open, allowing the fire-fighting fluid to be delivered through pipelines to the thermal runaway battery pack, immersing the cells for cooling. This completely dissipates the heat from the thermal runaway cells and surrounding cells, effectively controlling the cell temperature for a prolonged period to prevent reignition.

[0025] Example 2;

[0026] like Figure 1 As shown, a battery pack, a PACK-level gas-liquid fire extinguishing device, has a pressure relief valve 300 on the upper cover of the battery module 400 for thermal runaway pressure relief and auxiliary fire-fighting fluid injection. The pressure relief valve has a dual function: first, to prevent the battery pack from bursting due to excessive internal pressure in the event of thermal runaway; second, to relieve pressure during fire-fighting fluid delivery, since the battery pack is sealed, so that the fire-fighting fluid can be smoothly delivered into the battery pack.

[0027] The above embodiments are not intended to limit the present invention. Unless otherwise explicitly specified and limited, the terms "set," "install," "connect," and "link" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; a mechanical connection or an electrical connection; a direct connection or an indirect connection through an intermediate medium; or a connection within two components. Those skilled in the art can understand the specific meaning of the above terms in this application based on the specific circumstances. The present invention is not limited to the examples above. Changes, modifications, additions, or substitutions made by those skilled in the art within the scope of the technical solution of the present invention are also within the protection scope of the present invention. Furthermore, the technical features involved in the different embodiments of the present application described above can be combined with each other as long as they do not conflict with each other.

Claims

1. A PACK-grade gas-liquid fire extinguishing device, characterized in that, Including gas extinguishing units and liquid extinguishing units; The gas extinguishing unit includes a prefabricated perfluorohexanone extinguishing device (102) and a thermal wire (101) attached to the battery module. The end of the thermal wire (101) is connected to the electric ignition head of the perfluorohexanone extinguishing device (102). The liquid fire extinguishing unit includes a multi-stage pipeline (201) that runs around the battery pack and is connected by a fire detection tube. The input section of the multi-stage pipeline (201) is equipped with a solenoid valve group and forms a liquid fire extinguishing interface (202) that connects to the liquid cooling system. The solenoid valve group includes a first solenoid valve (203) and a second solenoid valve (204) arranged in series. A liquid level sensor (205) is provided in the multi-stage pipeline (201) between the first solenoid valve (203) and the second solenoid valve (204). The feedback signal harness of the perfluorohexanone fire extinguishing device (102), the control signal harness of the first solenoid valve (203) and the second solenoid valve (204), and the acquisition signal harness of the liquid level sensor (205) are all connected to the solenoid valve control module.

2. The PACK-level gas-liquid fire extinguishing device according to claim 1, characterized in that: The multi-stage pipeline (201) includes a primary pipeline (201a), a secondary pipeline (201b), and a tertiary pipeline (201c). The primary pipeline (201a) is equipped with a first solenoid valve (203) and a second solenoid valve (204). The secondary pipeline (201b) branches from the primary pipeline (201a) and extends towards each battery cluster. The tertiary pipeline (201c) branches from the secondary pipeline (201b) and extends towards each battery pack.

3. The PACK-level gas-liquid fire extinguishing device according to claim 2, characterized in that: The first solenoid valve (203) is located near the liquid fire-fighting interface (202), and the second solenoid valve (204) is a one-way solenoid valve that controls the flow of fire-fighting liquid from the primary pipeline (201a) to the secondary pipeline (201b).

4. The PACK-level gas-liquid fire extinguishing device according to claim 3, characterized in that: The three-stage pipeline (201c) is located directly above each battery pack.

5. A battery pack, characterized in that, The PACK-level gas-liquid fire extinguishing device according to any one of claims 1-4 is provided with a pressure relief valve (300) on the upper cover of the battery module for thermal runaway pressure relief and auxiliary fire-fighting fluid injection.

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