A string type immersed nickel-hydrogen energy storage system

Abstract

The application discloses a kind of group string type immersion nickel hydrogen energy storage systems, including battery pack, the space with containing cooling liquid in the battery pack;Fire-fighting component, the fire-fighting component includes composite detector, fire extinguisher body, fire-fighting delivery pipe and spray head, the composite detector and the fire extinguisher body are electrically connected, the fire-fighting delivery pipe connects the fire extinguisher body with the spray head, the composite detector is installed to the outside of the battery pack, and the spray head is directed to the battery pack;Liquid cooling component, the liquid cooling component includes liquid cooling unit and liquid cooling pipeline, the liquid cooling pipeline includes main pipe and branch pipe, the main pipe connects the liquid cooling unit with the battery pack, and the two ends of the branch pipe are connected with the main pipe respectively, and the branch pipe is wrapped or wound on the fire-fighting delivery pipe.Compared with prior art, the application has the advantages of fast response speed and uniform cooling.

Description

Technical Field

[0001] This invention relates to the field of energy storage battery technology, and in particular to a string-type submerged nickel-metal hydride energy storage system. Background Technology

[0002] Existing mainstream lithium-ion battery energy storage cabinets have significant limitations. Their charge / discharge rates are relatively low, making it impossible to achieve high-rate charge / discharge operations. Furthermore, they often fail to meet real-time requirements in situations demanding rapid response, such as grid frequency regulation, severely limiting their application in high-dynamic performance scenarios. In stark contrast, nickel-metal hydride (NiMH) batteries exhibit significant advantages due to their unique electrochemical characteristics: they not only have higher energy density, enabling them to store more energy in a limited space, but their discharge rates can also reach over 15C. NiMH battery packs demonstrate high rate of charge and discharge and fast response speeds, providing an irreplaceable advantage over lithium-ion battery energy storage systems in core performance indicators such as millisecond-level power regulation and rapid power response required for grid frequency regulation. This offers a feasible solution to energy storage needs in high-dynamic scenarios.

[0003] However, in existing energy storage technologies, design flaws in the cooling system have become a key bottleneck restricting battery performance. Conventional battery packs using liquid cooling plates can only effectively cool the cells directly in contact with the plate. Heat from other cells within the pack must be indirectly transferred to the plate via heat conduction, resulting in low heat exchange efficiency. This non-uniform cooling method directly causes significant temperature differences among cells within the pack, leading to inconsistent internal resistance and imbalanced charge / discharge performance. Over long-term operation, this severely shortens battery life, increases system maintenance costs, and may even pose safety hazards due to localized overheating, failing to fully realize the performance potential of nickel-metal hydride batteries in high-rate charge / discharge scenarios. Therefore, the slow response speed of lithium-ion battery storage cabinets and the uneven cooling of conventional liquid cooling methods urgently need to be addressed. In view of this, a string-type submerged nickel-metal hydride energy storage system is proposed. Summary of the Invention

[0004] The purpose of this invention is to provide a string-type submerged nickel-hydrogen energy storage system to solve the problems pointed out in the background art.

[0005] The above-mentioned technical objective of the present invention is achieved through the following technical solution:

[0006] A string submerged nickel-hydrogen energy storage system includes:

[0007] A battery pack having a space for containing coolant;

[0008] A fire-fighting assembly, comprising a composite detector, a fire extinguisher body, a fire delivery pipe, and a nozzle, wherein the composite detector and the fire extinguisher body are electrically connected, the fire delivery pipe connects the fire extinguisher body and the nozzle, the composite detector is installed on the outside of the battery pack, and the nozzle points towards the battery pack;

[0009] A liquid cooling assembly, comprising a liquid cooling unit and liquid cooling pipes, the liquid cooling pipes comprising a main pipe and branch pipes, the main pipe connecting the liquid cooling unit and the battery pack, the two ends of the branch pipes being connected to the main pipes respectively, and the branch pipes covering or wrapping around the fire-fighting delivery pipe.

[0010] In a preferred embodiment, a first electrically controlled valve and a second electrically controlled valve are respectively provided at both ends of the branch pipe.

[0011] In a preferred embodiment, the liquid cooling assembly further includes a gas storage device, which includes a gas storage container and a gas delivery pipeline. The gas storage container is disposed on the gas delivery pipeline, and the two ends of the gas delivery pipeline are connected to the branch pipes. The two ends of the gas delivery pipeline are respectively provided with a third electrically controlled valve and a fourth electrically controlled valve.

[0012] In a preferred embodiment, the branch pipe includes a plurality of sub-pipes, which are arranged in a straight line.

[0013] In a preferred embodiment, a capacitive sensor is provided at the end of the branch pipe for sensing the state of the material in the branch pipe.

[0014] In a preferred embodiment, the gas storage container is configured as an airbag.

[0015] In a preferred embodiment, the main pipe is provided with an adjustment section, the adjustment section having at least one adjustment opening, and a gravity block being provided in the adjustment opening.

[0016] In a preferred embodiment, a connecting ring is provided on the adjusting opening, and a sealing cap is provided on the connecting ring, the sealing cap being threadedly connected to the connecting ring.

[0017] In a preferred embodiment, the fire extinguisher body is a non-pressurized perfluorohexanone fire extinguishing device.

[0018] In a preferred embodiment, the liquid cooling unit includes a unit supply water pipe, a unit return water pipe, a compressor, a condenser, an electronic expansion valve, a condensing fan, a plate heat exchanger, an electric heater, a circulating water pump, an expansion tank, a return water pressure sensor, a temperature sensor, a pressure sensor, and a quick-connect chuck. The main pipe is connected to the unit supply water pipe and the unit return water pipe via the quick-connect chuck. The unit supply water pipe and the unit return water pipe are connected to the plate heat exchanger to form a circulation loop. The unit supply water pipe and the unit return water pipe are respectively equipped with the temperature sensor and the pressure sensor. The circulating water pump and the expansion tank are located on the unit return water pipe. The electric heater is connected to the unit supply water pipe and the unit return water pipe. The condenser, compressor, plate heat exchanger, and electronic expansion valve are connected in sequence to form a circulation loop. The condensing fan is located corresponding to the condenser.

[0019] Compared with existing technologies, this invention provides a string-type submerged nickel-metal hydride energy storage system that achieves an organic integration of multiple technological effects through the collaborative design of its components. The liquid cooling component design breaks through the limitations of conventional liquid cooling plates. By directly introducing coolant into the battery pack, the cells are completely submerged, achieving direct and uniform cooling of all cells. This design solves the problem of low heat exchange efficiency caused by traditional liquid cooling methods, which can only cool cells directly in contact with the liquid cooling plate and require indirect heat transfer between internal cells. It significantly reduces the temperature difference between cells within the battery pack, thereby avoiding phenomena such as inconsistent internal resistance and unbalanced charge-discharge performance caused by uneven temperature. This not only extends battery life and reduces long-term system maintenance costs but also eliminates potential safety hazards caused by localized overheating.

[0020] Meanwhile, in the fire protection system, the composite detector can monitor the fire environment around the battery pack in real time. Once an alarm is detected, it can immediately form an electrical linkage with the fire extinguisher body and deliver the extinguishing medium to the nozzle pointing at the battery pack through the fire delivery pipe, so as to quickly and accurately extinguish the fire on the battery pack, effectively curb the spread of the fire, and ensure the safety of the system operation.

[0021] The branch pipes in the liquid cooling pipeline further enhance the functionality and reliability of the system. The two ends of the branch pipes are connected to the main pipe. By wrapping or winding them around the fire-fighting delivery pipe, the fire-fighting delivery pipe can be efficiently cooled by the flow of coolant in the event of a fire, preventing the fire-fighting delivery pipe from being damaged by high temperature, ensuring the stable operation of the fire-fighting system in emergency situations, and ensuring the smooth delivery of fire extinguishing media.

[0022] In addition, the branch pipes can be flexibly connected to other components with cooling requirements, further expanding the application range of the cooling system, improving the cooling efficiency and adaptability of the entire system, and enabling the energy storage system to form synergistic advantages in terms of performance, safety assurance and functional expansion, thus comprehensively optimizing the overall performance of the energy storage system. Attached Figure Description

[0023] Figure 1 This invention relates to a schematic diagram of the connection structure of the main pipe and branch pipes of a string-type submerged nickel-hydrogen energy storage system.

[0024] Figure 2 This invention relates to a schematic diagram of the cross-sectional structure of a branch pipe in a string-type submerged nickel-hydrogen energy storage system.

[0025] Figure 3 This invention relates to a structural schematic diagram of a fire-fighting component for a string-type submerged nickel-hydrogen energy storage system.

[0026] Figure 4 This invention relates to a schematic diagram of the connection structure of branch pipes and fire-fighting delivery pipes in a string-type submerged nickel-hydrogen energy storage system.

[0027] Figure 5 This invention relates to a schematic diagram of the structure of a small cabinet for implementing a string-type submerged nickel-hydrogen energy storage system.

[0028] Figure 6 This invention relates to a schematic diagram of the structure of an outdoor cabinet for implementing a string-type submerged nickel-hydrogen energy storage system.

[0029] Figure 7 This invention relates to a schematic diagram of the main regulating section of a string-type submerged nickel-hydrogen energy storage system.

[0030] Figure 8 This invention relates to a schematic diagram of the structure of a liquid-cooled unit for a string-type submerged nickel-hydrogen energy storage system.

[0031] In the picture

[0032] 1. Battery pack; 2. Main pipe; 3. Adjustment section; 4. Adjustment opening; 5. Gravity block; 6. Connecting ring; 7. Sealing cover; 8. Branch pipe; 9. Sub-pipe; 10. Capacitive sensor; 11. First electrically controlled valve; 12. Second electrically controlled valve; 13. Gas storage container; 14. Gas transmission pipeline; 15. Third electrically controlled valve; 16. Fourth electrically controlled valve; 17. Unit water supply pipeline; 18. Unit return water pipeline; 19. Compressor; 20. Condenser; 21. Electronic expansion valve; 22. Condenser fan; 23. Plate heat exchanger; 24. Electric heater; 25. Circulating water pump; 26. Expansion tank; 27. Temperature sensor; 28. Pressure sensor; 29. ​​Quick-connect chuck; 30. Composite detector; 31. Fire extinguisher body; 32. Fire delivery pipe; 33. Nozzle. Detailed Implementation

[0033] The present invention will be further described in detail below with reference to the accompanying drawings.

[0034] This specific embodiment is merely an explanation of the present invention and is not intended to limit the invention. After reading this specification, those skilled in the art can make modifications to this embodiment without contributing any inventive step, but such modifications are protected by patent law as long as they are within the scope of the claims of the present invention.

[0035] like Figures 1 to 8 As shown, a string submerged nickel-hydrogen energy storage system includes:

[0036] Battery pack 1, wherein the battery pack 1 has a space for containing coolant;

[0037] The fire-fighting assembly includes a composite detector 30, a fire extinguisher body 31, a fire delivery pipe 32, and a nozzle 33. The composite detector 30 and the fire extinguisher body 31 are electrically connected. The fire delivery pipe 32 connects the fire extinguisher body 31 and the nozzle 33. The composite detector 30 is installed on the outside of the battery pack 1, and the nozzle 33 points towards the battery pack 1.

[0038] The liquid cooling assembly includes a liquid cooling unit and liquid cooling pipes. The liquid cooling pipes include a main pipe 2 and a branch pipe 8. The main pipe 2 connects the liquid cooling unit and the battery pack 1. The two ends of the branch pipe 8 are respectively connected to the main pipe 2. The branch pipe 8 is wrapped or wound around the fire-fighting delivery pipe 32.

[0039] This embodiment of a string-type submerged nickel-metal hydride energy storage system achieves an organic integration of multiple technological effects through the collaborative design of its components. The liquid cooling component design breaks through the limitations of conventional liquid cooling plates. By directly introducing coolant into the battery pack 1, the cells are completely immersed in the coolant, achieving direct and uniform cooling of all cells. This design solves the problem of low heat exchange efficiency caused by traditional liquid cooling methods, which can only cool cells directly in contact with the liquid cooling plate and require indirect heat transfer between internal cells. It significantly reduces the temperature difference between cells within the battery pack, thereby avoiding phenomena such as inconsistent internal resistance and unbalanced charge-discharge performance caused by uneven temperature. This not only extends the battery's lifespan and reduces the long-term maintenance costs of the system, but also eliminates potential safety hazards caused by localized overheating.

[0040] Meanwhile, in the fire protection system, the composite detector 30 can monitor the fire environment around the battery pack 1 in real time. Once an alarm is detected, it can immediately form an electrical linkage with the fire extinguisher body 31 and deliver the extinguishing medium to the nozzle 33 pointing to the battery pack 1 through the fire delivery pipe 32, so as to quickly and accurately extinguish the fire on the battery pack 1, effectively curb the spread of the fire, and ensure the safety of the system operation.

[0041] The branch pipe 8 in the liquid cooling pipeline further enhances the functionality and reliability of the system. The two ends of the branch pipe 8 are connected to the main pipe 2. By wrapping or winding it around the fire delivery pipe 32, the fire delivery pipe 32 can be efficiently cooled by passing in coolant in the event of a fire, so as to avoid damage to the fire delivery pipe 32 due to high temperature, ensure that the fire protection system can operate stably in emergency situations, and ensure the smooth delivery of fire extinguishing media.

[0042] In addition, branch pipe 8 can be flexibly connected to other components with cooling requirements, further expanding the application range of the cooling system, improving the cooling efficiency and adaptability of the entire system, and enabling the energy storage system to form synergistic advantages in terms of performance, safety and function expansion, thus comprehensively optimizing the overall performance of the energy storage system.

[0043] Furthermore, a first electrically controlled valve 11 and a second electrically controlled valve 12 are respectively provided at both ends of the branch pipe 8 to control the on / off state of the branch pipe 8, thereby controlling whether coolant is introduced into the branch pipe 8 according to different alarm levels. Specifically, in this embodiment, there are two alarm levels: a first-level alarm and a second-level alarm. A first-level alarm indicates a safety hazard, and a second-level alarm indicates an actual fire. The first electrically controlled valve 11 and the second electrically controlled valve 12 at both ends of the branch pipe 8 can precisely control the on / off state of the branch pipe 8 to adapt to the coolant supply requirements under different alarm levels and achieve flexible allocation of cooling resources. When the system triggers a first-level alarm, that is, when a safety hazard is detected, the two electrically controlled valves are opened to pre-introduce coolant into the branch pipe 8 to prepare for possible emergencies and ensure that the fire-fighting delivery pipe 32 is in a good pre-cooled state. If the alarm is subsequently cleared, the valves are closed and the coolant in the branch pipe 8 is drained, allowing the coolant to be used entirely for cooling the battery pack 1, avoiding unnecessary energy consumption and improving the operating efficiency of the cooling system. When a level-two alarm is triggered, confirming a real fire, the fire extinguisher body 31 is activated to spray fire extinguishing agent into the nozzle 33 through the fire delivery pipe 32. Simultaneously, the first and second electrically controlled valves 11 and 12 remain open, allowing coolant to continuously flow into the branch pipe 8. This continuously cools the fire delivery pipe 32, effectively preventing damage due to high temperatures during a fire, ensuring a stable supply of extinguishing agents, and guaranteeing efficient execution of the fire extinguishing action. This design, which dynamically adjusts the on / off state of the branch pipe 8 based on the alarm level, meets the cooling needs under different emergency conditions, achieves rational resource utilization, and further enhances the safety and economy of the entire energy storage system.

[0044] To maintain the system's airtightness and achieve smooth internal circulation, the liquid cooling assembly also includes a gas storage device. This device comprises a gas storage container 13 and a gas delivery pipe 14. The gas storage container 13 is mounted on the gas delivery pipe 14, and both ends of the gas delivery pipe 14 are connected to the branch pipe 8. A third electrically controlled valve 15 and a fourth electrically controlled valve 16 are respectively installed at both ends of the gas delivery pipe 14. Through the coordinated action of the gas storage container 13, the gas delivery pipe 14, and the third and fourth electrically controlled valves 16, a linkage mechanism is formed with the branch pipe 8 and the first and second electrically controlled valves 12, effectively ensuring the system's airtightness while simultaneously achieving precise control and efficient flow of the coolant within the branch pipe 8. Initially, the third and fourth electrically controlled valves 16 are open while the first and second electrically controlled valves 12 are closed, creating an annular channel between the branch pipe 8 and the gas delivery pipe 14, which communicates with the gas storage container 13, laying a sealed foundation for the subsequent entry and exit of the coolant. When a Level 1 alarm is triggered, the first, third, and fourth electrically controlled valves 16 open and the second electrically controlled valve 12 closes. Coolant enters the branch pipe 8 from the main pipe 2. With the help of the delivery pressure, the gas in the branch pipe 8 is squeezed into the gas delivery pipeline 14 and finally stored in the gas storage container 13. After the branch pipe 8 is filled with coolant, the third and fourth electrically controlled valves 16 are closed to seal the gas in the gas delivery pipeline 14. Then the second electrically controlled valve 12 is opened to allow the coolant to flow in the branch pipe 8. This ensures the pre-cooling preparation of the fire delivery pipe 32 when a Level 1 alarm is triggered, and the closed channel design prevents coolant leakage and maintains the smooth circulation within the system. When the Level 1 alarm is cleared and does not escalate to Level 2, after a preset 10-minute period, the system controls the first electrically controlled valve 11 to close, while simultaneously opening the second, third, and fourth electrically controlled valves 16. Utilizing the gas pressure stored in the gas pipeline 14, the coolant in the branch pipe 8 is rapidly discharged. After the coolant is completely discharged, the second electrically controlled valve 12 is closed. This process not only achieves efficient coolant recovery through gas pressure, allowing the coolant to be reused for cooling the battery pack 1 and avoiding resource waste, but also simplifies the operation process through orderly valve control, eliminating the need for additional power devices to complete the coolant discharge and improving the convenience of system control. Overall, the coordination between the gas storage device and the various electrically controlled valves ensures system tightness to maintain smooth internal circulation while achieving precise control of the coolant flow in and out of the branch pipe 8 under different operating conditions. This meets the cooling requirements under different alarm levels and improves the system's operating efficiency and economy through gas pressure drive and valve regulation, further optimizing the stability and adaptability of the entire energy storage system.

[0045] To maintain system stability, during the coolant entry into branch pipe 8, the opening of the first electrically controlled valve 11 is gradually increased, allowing the coolant to flow into branch pipe 8 smoothly. This avoids the impact on the pipeline caused by a sudden surge of large amounts of coolant, effectively reducing the risk of pipeline damage due to sudden stress and providing good pipeline protection. Simultaneously, this gradual opening adjustment makes the coolant flow from the main pipe 2 to branch pipe 8 more gradual, preventing abrupt fluctuations in flow rate from interfering with the overall stability of the cooling system. This ensures a smooth transition of parameters such as pressure and flow rate within the cooling system, avoiding large fluctuations that could affect normal cooling performance. During the coolant discharge from branch pipe 8, the openings of the third and fourth electrically controlled valves 15 and 16 are gradually increased, allowing the gas pressure in the gas delivery pipe 14 to gradually intervene. This makes the process of gas pressure driving the coolant out more smooth, avoiding sudden pressure changes in the pipeline caused by a large release of gas pressure, thus effectively reducing system fluctuations. This precise control of valve opening ensures a smooth transition during both the inflow and outflow of coolant. This not only protects the pipelines and related components, extending their service life, but more importantly, it ensures the stable operation of the entire energy storage system during coolant regulation. It also prevents adverse effects on the charging and discharging performance of the nickel-metal hydride batteries, the cooling effect, and the response reliability of the fire-fighting components caused by system fluctuations, further enhancing the overall stability and safety of the system.

[0046] In this embodiment, nitrogen is stored in the gas storage container 13. Nitrogen has good stability, which prevents it from mixing with the coolant or producing harmful substances during the coolant discharge process. This ensures that the purity of the coolant is not affected, facilitates coolant recycling, and maintains the high-efficiency cooling performance of the cooling system. Furthermore, even in high-temperature environments that may occur in the system, nitrogen will not decompose or expand abnormally due to temperature increases, maintaining a stable pressure. This ensures the controllability and continuity of the pressure during coolant discharge, guaranteeing that the coolant can be smoothly and completely discharged from the branch pipe 8, avoiding problems such as incomplete drainage or pipe impact caused by unstable pressure.

[0047] The branch pipe 8 includes multiple sub-pipes 9 arranged in a straight line. This design, consisting of multiple sub-pipes 9 arranged in a straight line, offers significant advantages in both cooling effect and coolant discharge efficiency. From a cooling effect perspective, the slender nature of the sub-pipes 9 allows them to fit more closely to the surface of the object being cooled. Compared to a single, thicker branch pipe 8, this significantly increases the contact area with the object, allowing for more thorough heat exchange between the coolant and the object as it flows within the sub-pipes 9. This avoids the problems of insufficient heat exchange and poor localized fit that can occur with thicker pipes, thus significantly improving cooling efficiency. It ensures more uniform temperature distribution across the cooled components and further enhances the cooling protection of components such as the fire-fighting delivery pipe 32, providing a more reliable guarantee for the stable operation of the fire-fighting system in high-temperature environments. From the perspective of coolant discharge, the smaller diameter of the micropipe 9 results in less residual space within the pipe when coolant is discharged using air pressure. This allows the air pressure to act more evenly and thoroughly on the coolant, propelling it along the inner wall of the micropipe 9 and effectively reducing the amount of coolant remaining in the pipe, achieving more complete and exhaustive discharge. This design not only optimizes cooling performance and ensures maximum cooling effect but also improves efficiency in the coolant recovery process, avoiding resource waste. Furthermore, the reduced residual amount lowers the potential risks of corrosion or freezing caused by coolant stagnation in the pipes, extending the service life of the pipes and making the entire system more efficient and stable in the cooling and drainage process.

[0048] The cross-section of the subdivision tube 9 can be set as a rectangular cross-section or a circular cross-section.

[0049] A capacitive sensor 10 is installed at the end of the branch pipe 8 to sense the state of the substance in the branch pipe 8. The capacitive sensor 10 at the end of the branch pipe 8 can accurately sense the presence of coolant in the branch pipe 8 and monitor the substance's state in real time. This feature provides timely feedback on the coolant's fullness or emptying, providing accurate data for the opening and closing of the electronically controlled valves, ensuring precise and controllable coolant flow and discharge.

[0050] Furthermore, the main pipe 2 is provided with an adjustment section 3, and the adjustment section 3 has at least one adjustment opening 4, in which a gravity block 5 is provided. When coolant enters the branch pipe 8, the gravity block 5 gradually descends, occupying more of the internal space of the main pipe 2, thereby reducing the effective capacity of the main pipe 2 and avoiding pressure imbalance caused by a sudden decrease in coolant flow in the main pipe 2 due to the branch pipe 8 diverting the flow, thus ensuring the stability of coolant delivery from the main pipe 2 to the battery pack 1. When coolant is discharged from the branch pipe 8, the gravity block 5 gradually rises, reducing its occupation of the internal space of the main pipe 2 and increasing the effective capacity of the main pipe 2 to adapt to the flow changes caused by coolant backflow, thus avoiding excessive pressure in the main pipe 2. This design of the gravity block 5, which automatically adjusts according to the coolant flow state, can achieve adaptive adjustment of the capacity of the main pipe 2 through the balance of its own gravity and liquid flow pressure without the need for additional power drive. It effectively buffers the fluctuations in flow and pressure of the main pipe 2 caused by the coolant entering and exiting the branch pipe 8, ensuring the stable operation of the entire liquid cooling system.

[0051] To achieve a closed opening, a connecting ring 6 is provided on the adjusting opening, and a sealing cap 7 is provided on the connecting ring 6. The sealing cap 7 is threadedly connected to the connecting ring 6. The threaded connection between the connecting ring 6 and the sealing cap 7 on the adjusting opening reliably seals the opening, effectively preventing coolant leakage from the adjusting opening during flow within the main pipe 2. This ensures the airtightness of the liquid cooling system, guarantees smooth coolant circulation along the designed path, and maintains stable system pressure. Simultaneously, the threaded connection facilitates the disassembly and installation of the sealing cap 7, providing convenience for maintenance operations such as inspection and replacement of the gravity block 5. This ensures both the reliability of the sealing effect and the ease of system maintenance.

[0052] In this embodiment, the fire extinguisher body 31 is a non-pressurized perfluorohexanone fire extinguishing device. Perfluorohexanone has high fire extinguishing efficiency, can quickly suppress fires, and is environmentally friendly, causing no damage to the ozone layer and having a low greenhouse potential. The non-pressurized design eliminates the need for high-pressure storage, reducing the risk of device leakage and explosion, making storage and maintenance more convenient, and highly compatible with the safety requirements of energy storage systems, effectively ensuring the fire safety of battery pack 1.

[0053] In this embodiment, the liquid cooling unit includes a unit water supply pipe 17, a unit return water pipe 18, a compressor 19, a condenser 20, an electronic expansion valve 21, a condensing fan 22, a plate heat exchanger 23, an electric heater 24, a circulating water pump 25, an expansion tank 26, a return water pressure sensor 28, a temperature sensor 27, a pressure sensor 28, and a quick-connect chuck 29. The main pipe 2 is connected to the unit water supply pipe 17 and the unit return water pipe 18 via the quick-connect chuck 29. The unit water supply pipe 17 and the unit return water pipe 18 are connected to the plate heat exchanger 23. A plate heat exchanger 23 forms a circulation loop. Temperature sensor 27 and pressure sensor 28 are respectively installed on the unit's water supply pipe 17 and return pipe 18. Circulating water pump 25 and expansion tank 26 are located on the unit's return pipe 18. Electric heater 24 is connected to the unit's water supply pipe 17 and return pipe 18. Condenser 20, compressor 19, plate heat exchanger 23, and electronic expansion valve 21 are sequentially connected to form a circulation loop. Condensing fan 22 is installed corresponding to condenser 20. The liquid-cooled unit achieves efficient temperature control and energy exchange through two major circulation loops. In the refrigeration cycle, compressor 19 compresses the low-temperature, low-pressure refrigerant gas into a high-temperature, high-pressure gas and discharges it into condenser 20; condenser fan 22 accelerates airflow, causing the refrigerant to release heat and liquefy in condenser 20; the liquid refrigerant enters plate heat exchanger 23 after being throttled and depressurized by electronic expansion valve 21, where it absorbs heat from the coolant and vaporizes, thus cooling the coolant; the vaporized refrigerant is then drawn back into compressor 19, forming a closed-loop cycle.

[0054] In the cooling cycle, the circulating water pump 25 drives the coolant from the unit's return water pipe 18 into the plate heat exchanger 23. After exchanging heat with the refrigerant, the coolant's temperature decreases, and it is then transported to the main pipe 2 via the unit's supply water pipe 17, entering the battery pack 1 for cooling. The coolant, having absorbed heat, flows back from the unit's return water pipe 18, forming a cycle. The expansion tank 26 is used to balance system pressure fluctuations and ensure stable circulation. The electric heater 24 can heat the coolant in low-temperature environments, maintaining the system temperature within a suitable range. Temperature sensors 27 and pressure sensors 28 monitor coolant parameters in real time, providing data support for system control. The quick-connect chuck 29 facilitates the rapid connection and disconnection of the main pipe 2 and the unit, improving maintenance efficiency.

[0055] This design enables the liquid cooling unit to precisely control the coolant temperature, ensuring that battery pack 1 operates within its optimal operating temperature range and effectively extending battery life. The high heat exchange efficiency improves the system response speed, meeting the requirements of high-rate charging and discharging. The independent operation of the dual cycles, while cooperating with each other, enhances the system's stability and reliability. The modular structure and intelligent monitoring reduce maintenance difficulty and costs, comprehensively optimizing the overall performance of the energy storage system.

[0056] This embodiment of a string-type submerged nickel-metal hydride (NiMH) energy storage system further includes the following configuration: The NiMH battery energy storage system comprises a battery compartment, an electrical compartment, a PCS compartment, and a liquid-cooled unit compartment. The main components include a battery pack, a battery rack, and a battery container. The battery packs are assembled to form a battery rack. The battery cells in the battery packs are NiMH batteries with a nominal voltage of 1.2V, a nominal capacity of 6000mAh, and an AC internal resistance of 1.0mΩ. The battery pack is a 288S3P specification, with a voltage of 345.6V, a capacity of 18Ah, and an energy of 6.22KWh. The battery rack is a 2S1P specification, with each rack equipped with one 115KWPCS unit. The PCS DC voltage range is DC630-950V, and the AC side is AC400V. The wiring method is 3L+PE, and the AC side is connected to the grid after being connected to the circuit breaker. The battery stack is configured as 1S8p. The battery compartment of the energy storage system is a non-standard modular cabinet (4.200mm×1500mm×2500mm, WDH), equipped with waterproof, heat-insulating, corrosion-resistant, fireproof, sand-resistant, shockproof, and UV-resistant functions, achieving an IP54 protection rating. The system is also equipped with a Battery Management System (BMS), an EMS, and a perfluorohexanone fire suppression system to prevent overcharging and discharging of the batteries, effectively managing battery charging and discharging, and ensuring stable and reliable operation of the battery system. Regarding operational strategies, the BMS protection logic is as follows: when an alarm occurs in a battery cluster, the BMS will control corresponding actions; a level 1 alarm triggers a warning, a level 2 alarm reduces power, and a level 3 alarm causes the system to shut down. The BMS communicates with the PCS via CAN, with the EMU via RS485, and with the battery BMS module within the system via CAN. Battery voltage is input to the BMS module via a data acquisition harness. The protection logic of the PCS includes: shutting down when a PCS fails and reporting a fault signal to the EMU; zero power output when the available SOC uploaded by the BMS to the PCS is lower than the set value; shutdown when the PCS receives an external shutdown command; each unit consists of four PCS units, which communicate and interact internally via CAN and RS485. The EMU, as the system's communication hub, connects to all communication devices via Ethernet and serial ports, communicating with other system devices to achieve reliable, reasonable, and comprehensive monitoring, measurement, and control of the energy storage power station. It also possesses remote sensing, remote adjustment, and remote control functions, and can perform functions such as information acquisition, information processing and summarization, alarm protection, automatic control, historical data recording, and event recording. Furthermore, it supports demand control mode, peak-valley mode, and planned curve mode. EMU can convert other power system protocols into protocols that the background can recognize and parse and display. It can realize information transmission and synthesis between various automation devices, intelligent instruments and the system host computer. It can also be used as a general control substation and front-end machine of integrated automation system. It is suitable for various scenarios such as cloud platform and microgrid.In terms of fire protection, the fire suppression system includes a fire alarm controller, detection modules, fire suppression actuators, fire extinguishing agent delivery pipelines, nozzles, and detection / main control wiring harnesses, enabling low-power real-time monitoring, accurate early warning, and timely intervention in fire suppression. One fire alarm controller is installed inside the cabinet to receive detector data and upload it to the BMS and trigger the fire suppression system based on the detection results. The detection devices are divided into battery pack level and cabinet level, both consisting of composite detectors integrating four detection elements: CO, VOC, temperature, and smoke. The battery pack level detectors are externally mounted on the outside of the battery pack; the cabinet level detectors are installed on the top of the battery pack area. When the composite detector detects a fire hazard, it triggers an alarm signal and reports it to the fire alarm controller, which then triggers the fire suppression system. The execution subsystem employs both cabinet-based and battery pack-based fire suppression methods. It consists of a fire suppression actuator, a non-pressurized perfluorohexanone (PFH) fire suppression system, battery pack-level nozzles, suppression piping, and auxiliary accessories. The fire suppression actuator is installed above the batteries in the battery cabinet. The cabinet-based fire suppression system is a non-pressurized PFH system, and the battery pack-level nozzles are directly installed on the outside of the battery pack with the nozzles facing the pack. The execution subsystem is a single-release PFH system within the cabinet and a multi-release system within the battery pack. Its alarm and activation logic is as follows: When the cabinet's four-in-one composite detector sends a Level 1 alarm signal, the detector increases its sampling frequency, and the fire alarm controller uploads the Level 1 alarm information via CAN. Upon receiving a Level 2 alarm signal, the fire alarm controller initiates the fire suppression process and activates the non-pressurized PFH system. When the battery pack-level composite detector reaches level zero alarm, the detector increases its sampling frequency, the controller records the alarm information, and there is no external signal output. When it reaches level one alarm, the location of the safety hazard is determined, the fire alarm controller issues a warning and transmits the data to the BMS system. When it reaches level two alarm, the fire alarm controller initiates the fire extinguishing program, activating the suppression device within 0-30 seconds (time adjustable), and spraying perfluorohexanone agent three times according to the set program. Specifically, in the first stage, one spray is made, releasing 1 kg of extinguishing agent and then stopping. In the second stage, one spray is made every 15 minutes for the next 30 minutes, releasing 1 kg of extinguishing agent each time, for a total of two sprays. In addition, the energy storage cabinet adopts an external maintenance mode, with two clusters, each containing eight battery packs. The liquid cooling circuit adopts a parallel connection, and adjacent battery packs adopt a series connection. Each branch is independently monitored by a flow meter to ensure the flow rate and flow of coolant in each battery pack are balanced. Table 1 below shows the fire alarm level logic.

[0057] Table 1

[0058]

[0059] Table 2 below is the logic table for PACK-level fire alarm levels:

[0060] Table 2

[0061]

[0062] The insulation detection device detects leakage current and insulation conditions on the AC side of the system. It communicates with the EMU (Electronic Management Unit). Its protection logic is a two-level alarm classification. In severe cases (alarm), the system shuts down and uploads an alarm signal. After triggering, the information is transmitted to the EMU via R485 communication, and a passive contact signal is output to the system status indicator. The water ingress detection device detects water ingress on the system's busbar side. It communicates with the EMU. After water immersion is triggered, the information is transmitted to the EMU via R485 communication, and a passive contact signal is output to the system status indicator. The EMU then reports an alarm signal. The dehumidifier detects the environmental conditions of the copper busbar compartment in the system's busbar side distribution room. It communicates with the EMU. A dehumidifier is installed in the busbar compartment, but not in the battery compartment. After the unit's set temperature and humidity action values ​​are triggered, the information is transmitted to the EMU via R485 communication, and the EMU reports an alarm signal. Its protection logic is that the software reports alarm information in case of abnormality or fault. It reserves protection threshold settings and supports writing the set parameters to Flash (retained after power failure). The electricity meter communicates with the EMU via RS485. In case of abnormality or fault, the software reports alarm (fault) information. Its DI and DO interfaces are only reserved for future use. Wireless temperature measurement is used to measure the busbar temperature. At 40 degrees Celsius, the dehumidifier controls the exhaust fan; at 60 degrees Celsius for 30 seconds, the EMU reduces system power; at 80 degrees Celsius for 10 seconds, the system shuts down. In terms of power system composition, eight clusters are grouped together. Each cluster is connected to the PCS after passing through a high-voltage box. The output of the eight PCS units in parallel is combined through copper busbars to the circuit breaker, and then connected to the power grid via a transformer.

[0063] It should be noted that, in this document, relational terms such as "first" and "second" are used only to distinguish one entity or operation from another, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Furthermore, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or terminal device that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or terminal device. Unless otherwise specified, an element defined by the phrase "comprising..." or "including..." does not exclude the presence of additional elements in the process, method, article, or terminal device that includes said element. Additionally, in this document, "greater than," "less than," "exceeding," etc., are understood to exclude the stated number; "above," "below," "within," etc., are understood to include the stated number.

[0064] The above description of the embodiments is provided to facilitate understanding and use of the present invention by those skilled in the art. It is obvious to those skilled in the art that various modifications can be easily made to the embodiments, and the general principles described herein can be applied to other embodiments without creative effort. Therefore, the present invention is not limited to the above embodiments. Improvements and modifications made by those skilled in the art based on the disclosure of the present invention without departing from the scope of the present invention should be within the protection scope of the present invention.

Claims

1. A string-type submerged nickel-hydrogen energy storage system, characterized in that, include: A battery pack having a space for containing coolant; A fire-fighting assembly, comprising a composite detector, a fire extinguisher body, a fire delivery pipe, and a nozzle, wherein the composite detector and the fire extinguisher body are electrically connected, the fire delivery pipe connects the fire extinguisher body and the nozzle, the composite detector is installed on the outside of the battery pack, and the nozzle points towards the battery pack; A liquid cooling assembly, comprising a liquid cooling unit and liquid cooling pipes, the liquid cooling pipes comprising a main pipe and branch pipes, the main pipe connecting the liquid cooling unit and the battery pack, the two ends of the branch pipes being respectively connected to the main pipe, and the branch pipes covering or wrapping around the fire-fighting delivery pipe; The branch pipe is provided with a first electrically controlled valve and a second electrically controlled valve at both ends. The liquid cooling assembly also includes a gas storage device, which includes a gas storage container and a gas transmission pipeline. The gas storage container is located on the gas transmission pipeline. The two ends of the gas transmission pipeline are connected to the branch pipe. The two ends of the gas transmission pipeline are provided with a third electrically controlled valve and a fourth electrically controlled valve.

2. The string submersible nickel-hydrogen energy storage system according to claim 1, characterized in that, The branch pipe includes multiple sub-pipes, which are arranged in a straight line.

3. The string submersible nickel-hydrogen energy storage system according to claim 1, characterized in that, The end of the branch pipe is equipped with a capacitive sensor for sensing the state of the material in the branch pipe.

4. The string submersible nickel-hydrogen energy storage system according to claim 1, characterized in that, The gas storage container is configured as an airbag.

5. The string submersible nickel-hydrogen energy storage system according to claim 1, characterized in that, The main pipe is provided with an adjustment section, and the adjustment section is provided with at least one adjustment opening, and a gravity block is provided in the adjustment opening.

6. The string submerged nickel-hydrogen energy storage system according to claim 5, characterized in that, A connecting ring is provided on the adjustment opening, and a sealing cap is provided on the connecting ring. The sealing cap is connected to the connecting ring by a thread.

7. A string submersible nickel-hydrogen energy storage system according to any one of claims 1 to 6, characterized in that, The fire extinguisher body is a non-pressurized perfluorohexanone fire extinguishing device.

8. A string submersible nickel-hydrogen energy storage system according to any one of claims 1 to 6, characterized in that, The liquid-cooled unit includes a unit supply water pipe, a unit return water pipe, a compressor, a condenser, an electronic expansion valve, a condensing fan, a plate heat exchanger, an electric heater, a circulating water pump, an expansion tank, a return water pressure sensor, a temperature sensor, a pressure sensor, and a quick-connect chuck. The main pipe is connected to the unit supply water pipe and the unit return water pipe via the quick-connect chuck. The unit supply water pipe and the unit return water pipe are connected to the plate heat exchanger to form a circulation loop. The unit supply water pipe and the unit return water pipe are respectively equipped with the temperature sensor and the pressure sensor. The circulating water pump and the expansion tank are located on the unit return water pipe. The electric heater is connected to the unit supply water pipe and the unit return water pipe. The condenser, compressor, plate heat exchanger, and electronic expansion valve are connected in sequence to form a circulation loop. The condensing fan is located corresponding to the condenser.

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