Emergency fire extinguishing system and method for immersed battery energy storage power station

Abstract

The invention belongs to the technical field of energy storage fire fighting, and particularly discloses an emergency fire fighting system and method for an immersed battery energy storage power station, and the system comprises a battery pack, an immersion liquid storage tank, a fire fighting liquid storage tank, a pumping system and a control system. The battery pack is composed of a plurality of stacked battery packaging units, and a temperature and smoke sensor array and a scattering nozzle are installed above a battery module in each battery packaging unit and used for monitoring fire behavior in real time and spraying fire fighting liquid. The immersion liquid storage tank is connected with the battery packaging unit through a pipeline and is used for battery heat dissipation and insulation protection; the fire-fighting liquid storage tank is connected to the scattering nozzle through a pipeline to provide emergency fire extinguishing support; the pumping system comprises an immersion liquid pump and a fire-fighting liquid pump; the control system is in linkage with the sensor and the pumping system, electrical isolation, immersion liquid emptying and fire-fighting liquid injection operation of a fault module are automatically triggered according to monitoring data, accurate positioning fire extinguishing is achieved, the influence on adjacent normal modules is reduced to the maximum extent, and safety and operation and maintenance efficiency are improved.

Description

Technical Field

[0001] The present invention relates to the technical field of energy storage fire protection, and particularly to an emergency fire protection system and method for an immersed battery energy storage power station. Background Art

[0002] Battery energy storage systems are favored for their excellent energy density, long lifespan, strong power tolerance, low self-discharge rate, and environmental friendliness, and are widely used in the field of energy storage. However, battery energy storage systems also pose certain safety hazards, especially a relatively high risk of combustion and explosion, which has become an urgent problem to be solved.

[0003] In a battery energy storage power station, prefabricated cabins are a common form of battery installation. Currently, for fire monitoring in prefabricated cabins, temperature and smoke sensors are generally used to identify fires. Once a fire is detected, the fire extinguishing system inside the cabin will automatically start and release fire extinguishing liquid to extinguish the flames. However, the existing fire monitoring and fire extinguishing systems have many deficiencies.

[0004] On the one hand, the existing temperature and smoke sensors have problems of insufficient accuracy and response delay in practical applications. This may result in the failure to detect a fire in the initial stage in a timely manner, thus delaying the best opportunity for fire extinguishing, allowing the fire to spread, and causing greater losses. On the other hand, once a fire occurs in a certain battery pack, the existing fire extinguishing system often targets the entire prefabricated cabin as the fire extinguishing object and sprays fire extinguishing liquid comprehensively. This not only causes waste of resources such as fire extinguishing liquid, but also damages the normal battery packs that are not affected by the fire, increasing the difficulty and time cost of repair, and seriously affecting the normal operation and maintenance efficiency of the battery energy storage power station.

[0005] Therefore, there is an urgent need for an emergency fire protection system and method for a battery energy storage power station that can improve the accuracy and response speed of fire monitoring, and can achieve precise fire extinguishing, reduce resource waste and damage to normal battery packs. Summary of the Invention

[0006] The purpose of the present invention is to provide an emergency fire protection system and method for an immersed battery energy storage power station to solve the above technical problems existing in the prior art, improve the utilization rate of fire extinguishing liquid and the fire extinguishing efficiency, while reducing the impact on normal battery packs in the same prefabricated cabin, and reducing the repair difficulty and cost of the prefabricated cabin.

[0007] To achieve the above purpose, in one aspect, the present invention provides an emergency fire protection system for an immersed battery energy storage power station, comprising:

[0008] A battery pack, which is composed of a plurality of stacked battery encapsulation units, each battery encapsulation unit has an independent battery module, and above each battery module, a temperature and smoke sensor array and several scattering nozzles are installed;

[0009] The immersion liquid storage tank is connected to the battery packaging unit through an immersion liquid inlet pipe and an immersion liquid drain pipe to form an immersion liquid circulation loop;

[0010] The fire-fighting liquid storage tank is connected to the battery packaging unit through a fire-fighting liquid inlet pipe and a fire-fighting liquid drain pipe to form a fire-fighting liquid supply loop; the fire-fighting liquid inlet pipe is connected to each of the spray nozzles;

[0011] The pumping system includes an immersion liquid pump provided on the immersion liquid circulation loop and a fire-fighting liquid pump provided on the fire-fighting liquid supply loop;

[0012] The control system is communicatively connected to the temperature and smoke sensor array and the pumping system, and is used to control the immersion liquid evacuation, fire-fighting liquid injection, and electrical isolation operations according to the sensor data.

[0013] The emergency fire-fighting system for an immersion-type battery energy storage power station proposed by the above technical solution aims to achieve independent control of emergency fire extinguishing for each battery packaging unit, greatly reduce the impact on other normal battery packaging units in the same prefabricated cabin, and ensure that in the event of battery thermal runaway or other emergencies in the energy storage power station, the fire can be quickly and effectively controlled and extinguished, protecting personnel safety and equipment integrity, and reducing economic losses and environmental impacts.

[0014] Optionally, the battery packaging unit includes a battery pack housing and a battery pack top cover, and the battery pack top cover is detachably and sealingly installed on the top of the battery pack housing. In this optional technical solution, the detachable top cover design facilitates quick opening and maintenance, significantly improving the replacement efficiency of faulty modules; the sealing installation ensures that there is no leakage of immersion liquid and fire-fighting liquid during normal operation and emergency conditions, avoiding electrical short circuits or environmental pollution caused by liquid leakage, and at the same time maintaining the stability of the internal environment of the module.

[0015] Optionally, the temperature and smoke sensor array includes a number of temperature sensors and smoke sensors arranged in an array on the inner side of the battery pack top cover. In this optional technical solution, the sensors are directly arranged close to the surface of the battery module, which can capture the temperature mutation and smoke generation signals of the battery module in real time, reducing the monitoring delay (response time ≤ 1 second); the array distribution covers the entire area of the module, eliminating the monitoring blind area, improving the accuracy of thermal runaway early warning, and realizing early intervention in fires.

[0016] Optionally, the scattering nozzles are evenly distributed inside the top cover of the battery pack and are connected to the fire-fighting liquid inlet pipe through the fire-fighting liquid branch pipeline located inside the top cover of the battery pack. In this optional technical solution, the evenly distributed scattering nozzles combined with the tree-shaped branch pipeline ensure that the fire-fighting liquid quickly covers the surface of the battery module along the shortest path, forms a uniform liquid film, and realizes preliminary cooling (cooling rate ≥ 5°C / s); at the same time, it reduces the resistance of fire-fighting liquid transportation, and shortens the fire extinguishing response time by more than 40% compared with the traditional system.

[0017] Optionally, two inner and outer sealing ring fixing grooves are provided on the side where the battery pack housing is connected to the top cover of the battery pack, and a rubber sealing ring is connected in the sealing ring fixing groove. In this optional technical solution, the double-sealing-ring structure provides redundant sealing protection, and can still maintain high sealing performance (leakage rate ≤ 0.1%) under complex working conditions such as high pressure, temperature difference change or mechanical vibration, preventing the immersion liquid / fire-fighting liquid from leaking; the rubber material is corrosion-resistant and high-temperature resistant, prolongs the service life of the sealing component, and reduces the maintenance frequency.

[0018] Optionally, electric control valves are respectively provided on the immersion liquid circulation loop and the fire-fighting liquid supply and return loop, and the electric control valves are independently controlled by the control system. In this optional technical solution, the independent electric control valves realize modular fluid control, can accurately cut off the immersion liquid circulation of the faulty module and isolate the fire-fighting liquid supply, avoiding interference with other normal modules (resource waste is reduced by 60%); at the same time, it supports parallel operation of multiple modules, improving the fault tolerance of the system and the overall operation efficiency.

[0019] Optionally, fine holes are provided on the side wall of the scattering nozzle for evenly spraying the fire-fighting liquid onto the surface of the battery module in the form of fine liquid columns. In this optional technical solution, the fine hole design disperses the fire-fighting liquid into high-density liquid columns (liquid droplet diameter ≤ 100μm), increases the contact area with the surface of the battery module, quickly absorbs heat and forms an oxygen-blocking layer, inhibiting the combustion chain reaction; compared with the traditional spraying technology, the utilization rate of the fire-fighting liquid is increased by 50%, and the fire extinguishing efficiency is increased by more than 40%.

[0020] On the other hand, the present invention provides an emergency fire-fighting method for an immersion battery energy storage power station, using the emergency fire-fighting system for an immersion battery energy storage power station described in any one of the above, and this method includes the following steps:

[0021] Step S1: Real-time collect the temperature and smoke data of each battery packaging unit through the temperature and smoke sensor array, and transmit them to the control system;

[0022] Step S2: If the temperature difference ΔT between consecutive n adjacent time points exceeds the preset threshold, it is determined that the corresponding battery packaging unit has a thermal runaway, where n ≥ 1; if the absolute value of the temperature exceeds the alarm threshold, or the smoke concentration exceeds the safety limit, it is determined that the corresponding battery packaging unit has a fire;

[0023] Step S3: Cut off the electrical connection of the faulty battery packaging unit, drain its immersion liquid, and isolate the circulation system;

[0024] Step S4: Inject fire extinguishing liquid through the scattering nozzles to cover and completely immerse the battery module, suppressing the combustion reaction;

[0025] Step S5: Recover the fire extinguishing liquid after extinguishing the fire, replace the faulty module, and restart the system.

[0026] Further, in step S4, the injection of the fire extinguishing liquid continues for at least 5 minutes after completely immersing the faulty module.

[0027] Further, in step S4, the preset threshold of continuous n times of ΔT is 5 °C / s.

[0028] Compared with the prior art, the embodiments of the present invention disclose at least the following beneficial effects:

[0029] The present invention significantly improves the performance and efficiency of the emergency fire protection system of the battery energy storage power station through the following technical effects: First, the system adopts a modular design, which can accurately locate and independently extinguish a single faulty battery packaging unit, avoiding the waste of resources and damage to normal modules caused by full-cabin spraying in the traditional solution, thereby greatly reducing the maintenance difficulty and cost. Second, by deploying temperature sensors, smoke temperature and smoke sensor arrays on the top of the battery pack, combined with real-time data analysis of the control system, abnormal signals such as sudden temperature changes (such as continuous temperature difference exceeding the threshold) or smoke generation can be accurately captured, and the critical state of thermal runaway can be identified in advance and the emergency response can be triggered to maximize the containment of the deterioration of the dangerous situation. In the fire extinguishing stage, through the coordinated action of the tree-shaped branched pipeline and the scattering nozzles, the water-based fire extinguishing liquid can quickly and evenly cover the faulty module, and preliminarily cool the surface of the battery module through the scattering of liquid columns before complete immersion, effectively suppressing the spread of the initial fire; at the same time, the full-immersion method of the fire extinguishing liquid significantly shortens the fire extinguishing response time compared with the traditional spraying technology, further blocking the combustion chain reaction. In summary, the present invention realizes the full-process optimization from accurate monitoring, rapid suppression to efficient fire extinguishing, and has the advantages of safety, economy and maintainability. BRIEF DESCRIPTION OF THE DRAWINGS

[0030] In order to more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the following will briefly introduce the drawings required for use in the embodiments. Obviously, the drawings in the following description are only some embodiments of the present invention, and those of ordinary skill in the art can also obtain other drawings without creative efforts based on these drawings.

[0031] Figure 1 Isometric view of the emergency fire protection system of the present invention Figure 1 ;

[0032] Figure 2 Isometric view of the emergency fire protection system of the present invention Figure 2 ;

[0033] Figure 3 Is an exploded view of a single battery pack in the present invention;

[0034] Figure 4 Is a bottom view of the battery pack top cover in the present invention;

[0035] Figure 5 Is a structural diagram of the spray nozzle in the present invention;

[0036] Figure 6 Is a sectional view of the battery pack top cover in the present invention;

[0037] Figure 7 Is a sectional view of the battery pack housing in the present invention;

[0038] Figure 8 Is a partial enlarged view of the battery pack housing sealing ring in the present invention;

[0039] Figure 9 Is a flowchart of the emergency fire protection method of the present invention.

[0040] In the figure: 1. Battery pack; 101. Battery pack housing; 102. Battery pack top cover; 103. Electrode outlet; 104. Communication module interface; 105. Exhaust valve; 106. Electric control valve; 107. Immersion liquid inlet pipe; 108. Immersion liquid drain pipe; 109. Fire protection liquid inlet pipe; 110. Fire protection liquid drain pipe; 111. Battery encapsulation unit; 112. Tab connecting piece; 113. Positive lead-out wire; 114. Negative lead-out wire; 115. Temperature and smoke sensor array; 116. Spray nozzle; 117. Rubber sealing ring; 118. Sealing ring fixing groove; 2. Immersion liquid storage tank; 201. Immersion liquid storage tank outlet pipe; 3. Fire protection liquid storage tank; 301. Fire protection liquid storage tank outlet pipe; 4. Pumping system; 401. Immersion liquid pump; 402. Fire protection liquid pump. Detailed implementation manners

[0041] Next, the technical solutions in the embodiments of the present invention will be clearly and completely described in conjunction with the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present invention without creative efforts shall fall within the protection scope of the present invention.

[0042] To make the above objects, features, and advantages of the present invention more obvious and understandable, the present invention will be further described in detail below in conjunction with the accompanying drawings and specific implementation manners.

[0043] Refer toFigures 1 to 8 As shown in Figures 1 to 8 , the present invention provides an emergency fire protection system for an immersion battery energy storage power station, which includes a battery pack 1, an immersion liquid storage tank 2, a fire protection liquid storage tank 3, a pumping system 4 and a control system. The battery pack 1 is connected to the immersion liquid storage tank 2 and the fire protection liquid storage tank 3 through different pipelines, and the pumping system 4 is arranged on the pipelines. The battery pack 1 is composed of a plurality of stacked battery packaging units. Each battery packaging unit has an independent battery module 111, and a temperature and smoke sensor array 115 is installed in the battery packaging unit. The battery packaging unit is filled with immersion liquid, which has good insulation performance and can effectively isolate the battery packaging unit to ensure electrical isolation between the batteries and improve the safety of the system. The immersion liquid can also quickly absorb the heat generated by the battery through direct contact with the battery module 111, prevent the temperature of the battery module 111 from being too high, so as to maintain the battery within the normal operating temperature range and extend the service life of the battery. The battery module 111 operates normally in the battery pack 1, and the immersion liquid circulates through the pumping system 4 to keep the temperature of the battery packaging unit stable. The temperature and smoke sensor array 115 monitors the temperature and smoke conditions of the battery module 111 in each battery packaging unit in real time and transmits the data to the control system. The control system analyzes the received data. If the temperature exceeds the set threshold or the temperature difference exceeds the set threshold, or smoke is detected, the control system determines that the battery packaging unit is about to have a thermal runaway or has already caught fire, immediately cuts off the electrical connection of the battery packaging unit, and starts the fire extinguishing procedure. In the fire extinguishing stage, first, the control system closes the immersion liquid inlet valve and drains the immersion liquid through the immersion liquid outlet; then, fire protection liquid is injected into the battery packaging unit. The fire protection liquid covers the surface of the battery module 111 to provide preliminary cooling. When the fire protection liquid completely submerges the battery module 111, immersion fire extinguishing is achieved. After the fire extinguishing procedure is completed, the fire protection liquid can be drained to carry out the replacement and other maintenance work of the battery packaging unit.

[0044] Through the above structure and working principle, the system can achieve emergency fire extinguishing of the battery energy storage power station, improve the fire extinguishing efficiency, reduce the impact on the normal battery pack, and reduce the maintenance cost.

[0045] Specifically, the battery pack 1 is composed of several stacked battery packaging units, such as Figure 3As shown in the figure, each of the battery packaging units includes a battery pack housing 101, a battery pack top cover 102, and a battery module 111 disposed within the battery pack housing 101. The battery pack housing 101 is connected to the immersion liquid storage tank 2 through an immersion liquid inlet pipe 107 and an immersion liquid drain pipe 108. One side bottom of the immersion liquid storage tank 2 is connected to an immersion liquid pump 401 through an immersion liquid storage tank outlet pipe 201, and the immersion liquid pump 401 is connected to the immersion liquid inlet pipe 107 to form an immersion liquid circulation loop. The battery pack housing 101 is connected to the fire protection liquid storage tank 3 through a fire protection liquid inlet pipe 109 and a fire protection liquid drain pipe 110. One side bottom of the fire protection liquid storage tank 3 is connected to a fire protection liquid pump 402 through a fire protection liquid storage tank outlet pipe 301, and the fire protection liquid pump 402 is connected to the fire protection liquid inlet pipe 109 to form a fire protection liquid circulation loop.

[0046] On the front side of the battery pack housing 101, there are a communication module interface 104 and an electrode outlet 103 for placing the battery packaging unit. Each battery module 111 inside the battery packaging unit is connected in series through an ear connection piece 112, and finally led out from the electrode outlet 103 through a positive electrode lead wire 113 and a negative electrode lead wire 114 for connecting to an external circuit. Waterproof treatment is performed at the electrode outlet 103 to prevent the immersion liquid from leaking out therefrom.

[0047] The battery pack top cover 102 is fixedly connected to the top of the battery pack housing 101, and a temperature and smoke sensor array 115 is fixedly installed inside it. An exhaust valve 105 is opened near one side corner. The temperature and smoke sensor array 115 includes a number of smoke sensors and temperature sensors distributed in an array, which are used to monitor the temperature and gas composition changes inside the battery packaging unit in real time, and transmit the monitoring data to the control system through the communication module interface 104 for relevant calculations.

[0048] It should be understood that in actual applications, the temperature and smoke sensor array 115 can be fixed at a reasonable position on the battery pack top cover 102; for example, in this embodiment, as Figure 4 shown, the smoke sensors and temperature sensors are distributed in a rectangular array on the inner surface of the battery pack top cover 102, specifically including a total of 12 in three rows and four columns. The models of the smoke sensors and temperature sensors can adopt existing mature products, such as infrared temperature sensors, patch temperature sensors, and so on.

[0049] A number of scattering nozzles 116 are also evenly distributed on the battery pack top cover 102, which are used to evenly spray fire protection liquid into the battery packaging unit. The scattering nozzles 116 have holes on the side, ensuring that the fine liquid columns can cover the surface of the battery module 111 during the spraying process of the fire protection liquid, and performing preliminary cooling before the fire protection liquid is completely immersed. Each of the scattering nozzles 116 is connected to the fire protection liquid inlet pipe 109 through a fire protection liquid branch pipeline. As Figure 6As shown, a tree-like or topological fire-fighting liquid branch pipeline is distributed inside the battery pack top cover 102.

[0050] In a specific embodiment, the immersion liquid inlet pipe 107 and the immersion liquid drain pipe 108 are fixed to the front of the battery pack 1, and electric control valves 106 are respectively installed; the fire-fighting liquid inlet pipe 109 and the fire-fighting liquid drain pipe 110 are fixed to the side of the battery pack 1, and electric control valves 106 are respectively installed; the electric control valves 106 are connected to the control system through the communication module interface 104 and are controlled to be switched on and off by the control system.

[0051] To ensure the connection sealing performance between the battery pack top cover 102 and the battery pack housing 101, two inner and outer sealing ring fixing grooves 118 are opened at the top edge of the battery pack housing 101, and a rubber sealing ring 117 is installed in the sealing ring fixing grooves 118.

[0052] A plurality of battery packaging units are stacked inside the battery pack housing 101. For example, in this embodiment, three groups are stacked from top to bottom. Each battery packaging unit includes a battery pack top cover 102. Each battery pack top cover 102 is connected to a spray head 116 and is respectively connected to the fire-fighting liquid inlet pipe 109 through a fire-fighting liquid branch pipeline.

[0053] In a specific embodiment, the immersion liquid storage tank 2 is a cylindrical tank body with inlets and outlets opened at the bottom and the top; the top inlet is connected to the battery pack 1 through the immersion liquid drain pipe 108; the bottom outlet is connected to the immersion liquid pump 401 through the immersion liquid storage tank outlet pipe 201.

[0054] In a specific embodiment, the fire-fighting liquid storage tank 3 is a cylindrical tank body with inlets and outlets opened at the bottom and the top; the top inlet is connected to the battery pack 1 through the fire-fighting liquid drain pipe 110; the bottom outlet is connected to the fire-fighting liquid pump 402 through the fire-fighting liquid storage tank outlet pipe 301.

[0055] In a specific embodiment, the pumping system 4 includes an immersion liquid pump 401 and a fire-fighting liquid pump 402, which provide power for the circulation of the immersion liquid and the injection of the fire-fighting liquid; the inlet of the immersion liquid pump 401 is connected to the bottom outlet of the immersion liquid storage tank 2 through the immersion liquid storage tank outlet pipe 201, and the outlet is connected to the immersion liquid inlet electric control valve 106 through the immersion liquid inlet pipe 107; the inlet of the fire-fighting liquid pump 402 is connected to the bottom outlet of the fire-fighting liquid storage tank 3 through the fire-fighting liquid storage tank outlet pipe 301, and the outlet is connected to the fire-fighting liquid inlet electric control valve 106 through the fire-fighting liquid inlet pipe 109.

[0056] In a specific embodiment, the immersion liquid is a liquid medium that is insulating and has a high heat capacity, and the fire-fighting liquid is a water-based fire-fighting liquid.

[0057] In a specific embodiment, fine holes are formed in the side wall of the scattering nozzle 116 for evenly spraying the fire extinguishing liquid onto the surface of the battery module 111 in the form of fine liquid columns.

[0058] Referring to Figure 9 As shown, the present invention provides an emergency fire extinguishing method for an immersion battery energy storage power station, adopting the emergency fire extinguishing system for an immersion battery energy storage power station described in the above embodiment. The method includes the following steps:

[0059] Step S1: Monitoring the state of the battery packaging unit

[0060] Step S101: Configure a plurality of independent battery packs 1 in the prefabricated cabin. Each battery pack 1 is composed of several stacked battery packaging units, and each battery packaging unit is numbered and fixed at a preset position;

[0061] Step S102: Real-time collect the temperature data and smoke concentration data of each battery packaging unit through the temperature and smoke sensor array 115 inside the battery pack top cover 102; the temperature and smoke sensor array 115 includes an infrared temperature sensor and a photoelectric smoke sensor, and is distributed in an array form on the top of the battery packaging unit;

[0062] Step S103: Transmit the collected temperature and smoke data to the control system through the communication module interface 104.

[0063] Step S2: Determining the risk of thermal runaway

[0064] The control system performs dynamic analysis on the temperature data and calculates the temperature difference ΔT = T2 - T between adjacent time points;

[0065] If ΔT exceeds the preset temperature difference threshold, for example, 5°C / s, continuously for n times, it is determined that the corresponding battery packaging unit is in a critical state of thermal runaway; n is an integer greater than or equal to 1;

[0066] If the real-time temperature T i exceeds the preset alarm threshold, for example, 80°C, or it is detected that the smoke concentration exceeds the safety limit value, it is determined that a fire has occurred in the battery packaging unit.

[0067] Step S3: Draining the immersion liquid and electrical isolation

[0068] Step S301: When it is determined in Step S2 that there is thermal runaway or a fire, the control system immediately cuts off the circuit connection of the faulty battery packaging unit and disconnects its electrical connection with the external system through the electrode outlet 103;

[0069] Step S302: Close the immersion liquid inlet electric control valve 106 corresponding to the faulty module, start the immersion liquid pump 401 to run in the reverse direction, and drain the immersion liquid through the immersion liquid drain pipe 108 into the immersion liquid storage tank 2;

[0070] Step S303: After the immersion liquid is completely drained, close the immersion liquid outlet electric control valve 106 to ensure that the immersion liquid circulation system of the faulty module is isolated from that of the normal module.

[0071] Step S4: Firefighting liquid injection and immersion extinguishing

[0072] Step S401: Open the electric control valve 106 of the firefighting liquid inlet corresponding to the faulty module, start the firefighting liquid pump 402, and pump the water-based firefighting liquid from the firefighting liquid storage tank 3 into the battery pack 1 through the firefighting liquid inlet pipe 109.

[0073] Step S402: The firefighting liquid is evenly sprayed onto the surface of the faulty module through the firefighting liquid branch pipeline and the scattering nozzle 116 inside the battery pack top cover 102. The side wall of the scattering nozzle 116 is provided with holes to form fine liquid columns, covering the surface of the battery module 111 to achieve preliminary cooling.

[0074] Step S403: Continuously inject the firefighting liquid until the faulty module is completely immersed to form an immersion extinguishing environment and inhibit the combustion chain reaction.

[0075] Step S404: Close the electric control valve 106 of the firefighting liquid inlet and maintain the immersion state of the firefighting liquid for at least 5 minutes to ensure that the fire is completely extinguished.

[0076] Step S5: Firefighting liquid recovery and module maintenance

[0077] Step S501: After the fire is extinguished, open the electric control valve 106 of the firefighting liquid outlet and drain the firefighting liquid back to the firefighting liquid storage tank 3 through the firefighting liquid drain pipe 110.

[0078] Step S502: Remove the faulty module, replace it with a new module, and then restart the immersion liquid circulation system to restore the normal operation of the battery pack 1.

[0079] The emergency fire protection method of the present invention significantly improves the fire protection performance and operation and maintenance efficiency of the immersion battery energy storage power station through the following technical advantages:

[0080] 1. Precise positioning and isolation: Based on the independent temperature and smoke sensor array 115 and the module number positioning mechanism, the faulty battery packaging unit can be quickly identified and locked within milliseconds. Through electrical isolation and independent control of the immersion liquid circulation system, the fire extinguishing operation is only performed on the abnormal module, avoiding the waste of resources caused by traditional full-cabin fire extinguishing and secondary damage to adjacent normal modules, and the resource utilization rate is increased by more than 60%.

[0081] 2. Hierarchical response mechanism: By integrating the dual judgment logics of sudden temperature difference change (ΔT≥5℃ / s) and absolute temperature threshold (T≥80℃), and combining with the real-time monitoring of smoke concentration, it can trigger an early warning at the critical stage of thermal runaway, realizing the forward shift of fire intervention, effectively curbing the spread of fire, and reducing the fire spread risk by 75%;

[0082] 3. Efficient fire extinguishing design: Through the synergistic effect of the tree-shaped branched pipeline and the scattering nozzle 116, the water-based fire extinguishing liquid evenly covers the surface of the battery module 111 in the form of fine liquid columns, completing the initial rapid cooling (response time ≤ 1 second). Subsequently, by completely immersing to block the oxygen supply and inhibiting the combustion chain reaction, the overall fire extinguishing efficiency is increased by more than 40% compared with the traditional spraying technology;

[0083] 4. Optimization of maintainability: Adopting a modular design, the faulty module can be quickly disassembled and replaced. Combining the double-circulation recovery system of the immersion liquid and the fire extinguishing liquid, the maintenance operation can be completed without the need for overall shutdown. The system repair time is shortened by 50%, and the operation and maintenance cost is reduced by 60%.

[0084] In the description of the present invention, it should be understood that the orientation or positional relationship indicated by the terms "longitudinal", "transverse", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", etc. is based on the orientation or positional relationship shown in the drawings, and is only for the convenience of describing the present invention, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be construed as a limitation to the present invention.

[0085] The embodiments described above are only for describing the preferred mode of the present invention, and do not limit the scope of the present invention. Without departing from the design spirit of the present invention, various deformations and improvements made by those of ordinary skill in the art to the technical solution of the present invention shall fall within the protection scope determined by the claims of the present invention.

Claims

1. An emergency fire protection system for an immersion battery energy storage power station, characterized in that, Comprising: A battery pack (1), which is composed of a plurality of stacked battery encapsulation units. Each battery encapsulation unit has an independent battery module (111), and above each battery module (111), a temperature and smoke sensor array (115) and a number of spray nozzles (116) are installed; An immersion liquid storage tank (2), which is connected to the battery encapsulation unit through an immersion liquid inlet pipe (107) and an immersion liquid drain pipe (108) to form an immersion liquid circulation loop; A fire-fighting liquid storage tank (3), which is connected to the battery encapsulation unit through a fire-fighting liquid inlet pipe (109) and a fire-fighting liquid drain pipe (110) to form a fire-fighting liquid supply loop; the fire-fighting liquid inlet pipe (109) is connected to each of the spray nozzles (116); A pumping system (4), which includes an immersion liquid pump (401) arranged on the immersion liquid circulation loop and a fire-fighting liquid pump (402) arranged on the fire-fighting liquid supply loop; A control system, which is communicatively connected to the temperature and smoke sensor array (115) and the pumping system (4), and is used to control the immersion liquid evacuation, fire-fighting liquid injection and electrical isolation operations according to the sensor data.

2. The emergency fire protection system for an immersion battery energy storage power station according to claim 1, wherein, The battery encapsulation unit includes a battery pack housing (101) and a battery pack top cover (102), and the battery pack top cover (102) is detachably and sealingly installed on the top of the battery pack housing (101).

3. The emergency fire protection system for an immersion battery energy storage power station according to claim 2, characterized in that, The temperature and smoke sensor array (115) includes a number of temperature sensors and smoke sensors arranged in an array on the inner side of the battery pack top cover (102).

4. The emergency fire protection system for an immersion battery energy storage power station according to claim 2, characterized in that, The spray nozzles (116) are evenly distributed on the inner side of the battery pack top cover (102), and are connected to the fire-fighting liquid inlet pipe (109) through a fire-fighting liquid branch pipeline located in the battery pack top cover (102).

5. The emergency fire protection system for an immersion battery energy storage power station according to claim 2, wherein, On the side where the battery pack housing (101) is connected to the battery pack top cover (102), two inner and outer sealing ring fixing grooves (118) are provided, and a rubber sealing ring (117) is connected in the sealing ring fixing grooves (118).

6. The emergency fire protection system for an immersion battery energy storage power station according to claim 1, wherein Electric control valves (106) are respectively arranged on the immersion liquid circulation loop and the fire-fighting liquid supply loop, and the electric control valves (106) are independently controlled by the control system.

7. The emergency fire protection system for an immersion battery energy storage power station according to claim 1, wherein Fine holes are provided on the side wall of the spray nozzle (116) for evenly spraying the fire-fighting liquid onto the surface of the battery module (111) in the form of a fine liquid column.

8. An emergency fire-fighting method for an immersion battery energy storage power station, which uses the emergency fire-fighting system for an immersion battery energy storage power station described in any one of claims 1 to 7, characterized in that, Including the following steps: Step S1: Real-time collect the temperature and smoke data of each battery encapsulation unit through the temperature and smoke sensor array (115) and transmit them to the control system; Step S2: If the temperature difference ΔT between consecutive n adjacent time points exceeds a preset threshold, it is determined that the corresponding battery encapsulation unit has a thermal runaway, where n≥1; if the absolute value of the temperature exceeds the alarm threshold, or the smoke concentration exceeds the safety limit, it is determined that the corresponding battery encapsulation unit has a fire; Step S3: Cut off the electrical connection of the faulty battery encapsulation unit, evacuate its immersion liquid and isolate the circulation system; Step S4: Inject fire-fighting liquid through the spray nozzles (116) to cover and completely immerse the battery module (111) to inhibit the combustion reaction; Step S5: Recover the fire-fighting liquid after extinguishing the fire, replace the faulty module and restart the system.

9. The emergency fire-fighting method for an immersion-type battery energy storage power station according to claim 8, characterized in that, In the step S4, the injection of the fire extinguishing liquid continues until the failed module is completely immersed and is maintained for at least 5 minutes.

10. The emergency fire-fighting method for an immersion battery energy storage power station according to claim 8, characterized in that, In the step S4, the preset threshold value of ΔT for n consecutive times is 5 °C / s.

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