An immersion liquid cooling liquid level management system

Abstract

This invention provides a submersible liquid-cooled level management system, belonging to the field of energy storage system level management technology. It includes multiple level gauges, a battery management system, an oil cooling unit, and a submersible fluid replenishment unit. The multiple level gauges monitor the level of the submersible fluid inside the tank. The battery management system observes the current level information and can control the operation of the oil cooling unit and the submersible fluid replenishment unit separately to achieve the circulation and replenishment of the submersible fluid inside the tank. This submersible liquid-cooled level management system provides real-time monitoring and closed-loop control of the submersible fluid level inside the tank, enabling precise regulation of the submersible fluid level and eliminating operational risks caused by abnormal fluid levels.

Description

Technical Field

[0001] This utility model belongs to the field of energy storage system liquid level management technology, and more specifically, it relates to an immersion liquid-cooled liquid level management system. Background Technology

[0002] As the core unit of electrochemical energy storage systems, battery cells pose a significant risk of thermal runaway. Once thermal runaway occurs, the cell instantly releases a large amount of heat, which rapidly spreads to adjacent cells, triggering a chain reaction of thermal runaway at the module or even system level, ultimately leading to serious safety accidents such as fires or explosions. To address this issue, submerged liquid-cooled energy storage systems have been proposed and applied, which manage thermal runaway by encasing the battery cells in a circulating insulating coolant (such as synthetic oil). However, existing submerged systems face the challenge of precisely controlling the coolant capacity: 1) If the coolant level is too high, the pressure inside the pack increases dramatically, causing structural deformation and seal failure, resulting in coolant leakage; 2) If the coolant level is too low, parts of the battery cell module are exposed outside the coolant coverage area, leading to uneven temperature distribution (temperature difference > 5°C) and the risk of fire barrier failure.

[0003] Therefore, there is an urgent need to develop a real-time monitoring and dynamic adjustment mechanism for the immersion liquid level of a single Pack unit to ensure that the liquid level is always maintained within the safe operating window. Utility Model Content

[0004] The purpose of this invention is to provide an immersion liquid-cooled level management system, which aims to solve the technical problem that the coolant capacity of current immersion liquid-cooled energy storage systems is not easy to accurately control.

[0005] To achieve the above objectives, the technical solution adopted by this utility model is: to provide an immersion liquid-cooled level management system, comprising:

[0006] Multiple level gauges are connected to a tank in an immersion liquid-cooled energy storage system for containing immersion liquid, the level gauges being adapted to measure the level of the immersion liquid in the tank;

[0007] A battery management system is electrically connected to multiple liquid level gauges, and the battery management system is used to receive liquid level information measured by multiple liquid level gauges.

[0008] An oil-cooled unit is electrically connected to the battery management system and its operation is controlled by the battery management system. The oil-cooled unit is connected to the housing of the immersion liquid-cooled energy storage system and is used to circulate the immersion liquid inside the housing.

[0009] The immersion liquid replenishment unit is electrically connected to the battery management system and its operation is controlled by the battery management system. The immersion liquid replenishment unit is connected to the housing of the immersion liquid-cooled energy storage system and is used to replenish the immersion liquid inside the housing.

[0010] In one possible implementation, the enclosure of the submerged liquid-cooled energy storage system has a liquid inlet and a liquid outlet, and the oil-cooled unit is connected to the liquid inlet and the liquid outlet respectively through multiple first pipes so that the submerged liquid forms a circulating flow.

[0011] In one possible implementation, the enclosure of the immersion liquid-cooled energy storage system also has a first replenishment port and a second replenishment port. The immersion liquid replenishment unit is connected to the first replenishment port and the second replenishment port through multiple second pipes to replenish the immersion liquid inside the enclosure.

[0012] In one possible implementation, the height of the first replenishment port is lower than the height of the second replenishment port.

[0013] In one possible implementation, both the first and second pipes are connected to a solenoid valve, which is electrically connected to the battery management system and whose operation is controlled by the battery management system.

[0014] In one possible implementation, the plurality of liquid level gauges include a high liquid level gauge and a low liquid level gauge. The high liquid level gauge is located at the high liquid level position of the immersion liquid and is used to monitor whether the liquid level of the immersion liquid is higher than the position measured by the high liquid level gauge. The low liquid level gauge is located at the high liquid level position of the immersion liquid and is used to monitor whether the liquid level of the immersion liquid is lower than the position measured by the low liquid level gauge. When the liquid level of the immersion liquid is higher than the position measured by the high liquid level gauge or lower than the position measured by the low liquid level gauge, the high liquid level gauge or the low liquid level gauge sends information to the battery management system to control the oil cooling unit to extract immersion liquid from the inside of the tank or to control the immersion liquid replenishment unit to replenish immersion liquid into the inside of the tank.

[0015] In one possible implementation, the immersion fluid replenishment unit includes an oil pump and an oil tank, the oil tank storing immersion fluid, the oil pump having an extraction end and a pumping end, the extraction end being connected to the oil tank, and the pumping end being connected to the first replenishment port or the second replenishment port via a second pipeline, the oil pump being electrically connected to the battery management system and its operation being controlled by the battery management system.

[0016] In one possible implementation, the side of the enclosure of the submerged liquid-cooled energy storage system is connected to a positive connector, a negative connector, and a low-voltage connector, and the top of the submerged battery pack is connected to an explosion-proof valve.

[0017] In one possible implementation, the outer wall of the submersible liquid-cooled energy storage system is closely attached to a cooling box, which is used to cool the box.

[0018] In one possible implementation, the cooling box is filled with coolant and connected to a refrigeration unit, which is used to circulate the coolant inside the cooling box. The coolant is adapted to exchange heat with the immersion liquid inside the box.

[0019] The beneficial effects of the immersion liquid-cooled level management system provided by this utility model are as follows: Compared with the prior art, the immersion liquid-cooled level management system of this utility model includes multiple level gauges, a battery management system, an oil cooling unit, and an immersion liquid replenishment unit. The multiple level gauges can monitor the level of the immersion liquid inside the tank, and the battery management system can observe the current level information and control the operation of the oil cooling unit and the immersion liquid replenishment unit respectively to realize the circulation of the immersion liquid inside the tank and replenish the immersion liquid inside the tank. This utility model realizes real-time monitoring and closed-loop control of the immersion liquid level inside the tank, and can accurately regulate the immersion liquid level, thereby eliminating the operational risks caused by abnormal liquid levels. Attached Figure Description

[0020] To more clearly illustrate the technical solutions in the embodiments of this utility model, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this utility model. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0021] Figure 1 This is a schematic diagram of the internal structure of the immersion liquid-cooled energy storage system of an immersion liquid-cooled level management system provided in an embodiment of the present utility model.

[0022] Figure 2 A schematic diagram of the front panel structure of the immersion liquid-cooled energy storage system of an immersion liquid-cooled level management system provided for an embodiment of this utility model;

[0023] Figure 3 Another structural schematic diagram of the front panel of the immersion liquid-cooled energy storage system of the immersion liquid-cooled level management system provided in this embodiment of the utility model;

[0024] Figure 4 A schematic diagram of the connection structure of an immersion liquid-cooled level management system provided in an embodiment of this utility model;

[0025] Figure 5A control flowchart for an immersion liquid-cooled level management system provided in an embodiment of this utility model.

[0026] Explanation of reference numerals in the attached figures:

[0027] 1. Immersion liquid; 2. Battery cell module; 3. Housing; 4. Liquid level meter; 5. Liquid inlet; 6. Liquid outlet; 7. First liquid replenishment port; 8. Second liquid replenishment port; 9. Positive connector; 10. Negative connector; 11. Low-voltage connector; 12. Explosion-proof valve; 13. Cooling housing. Detailed Implementation

[0028] To make the technical problems, technical solutions, and beneficial effects of this utility model clearer, the present utility model will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the present utility model and are not intended to limit the present utility model.

[0029] The applicant has discovered a problem in the existing technology: the level of the immersion liquid 1 cannot be monitored in real time. Immersion liquid 1 submerges the battery cell module 2. When there is too much immersion liquid 1, the internal pressure of the housing 3 (used to house the battery cell module 2) increases, leading to structural deformation of the housing 3 and leakage of the immersion liquid 1. Conversely, when there is too little immersion liquid 1, it cannot completely submerge the battery cell module 2, resulting in inconsistent temperatures and fire hazards. Therefore, it is necessary to monitor the level of the immersion liquid 1 in real time to reasonably control the level. When the level is below the set value, immersion liquid 1 should be replenished promptly; when the level is above the set value, a portion of the immersion liquid 1 should be removed promptly. Ultimately, the level of immersion liquid 1 should be maintained within a reasonable and stable range, which facilitates the management of the battery cell module 2.

[0030] Please refer to the following: Figures 1 to 5 The present invention provides a submersible liquid-cooled level management system. The submersible liquid-cooled level management system includes multiple level gauges 4, a battery management system, an oil cooling unit, and a submersible liquid replenishment unit. The multiple level gauges 4 are connected to the housing 3 of the submersible liquid-cooled energy storage system, which contains the submersible liquid 1 and the battery cell modules 2. The level gauges 4 are adapted to measure the level of the submersible liquid 1 inside the housing 3. The battery management system is electrically connected to the multiple level gauges 4 and receives the level information measured by the multiple level gauges 4. The oil cooling unit is electrically connected to the battery management system and its operation is controlled by the battery management system. The oil cooling unit is connected to the housing 3 of the submersible liquid-cooled energy storage system and is used to circulate the submersible liquid 1 inside the housing 3. The submersible liquid replenishment unit is electrically connected to the battery management system and its operation is controlled by the battery management system. The submersible liquid replenishment unit is connected to the housing 3 of the submersible liquid-cooled energy storage system and is used to replenish the submersible liquid 1 inside the housing 3.

[0031] This utility model provides an immersion liquid-cooled level management system. Compared with the prior art, it can monitor the level of the immersion liquid 1 inside the tank 3 through multiple level gauges 4. The battery management system can observe the current level information and control the operation of the oil cooling unit and the immersion liquid replenishment unit respectively, so as to realize the circulation of the immersion liquid 1 inside the tank 3 and replenish the immersion liquid 1 inside the tank 3. This utility model realizes real-time monitoring and closed-loop control of the immersion liquid 1 inside the tank 3, and can accurately regulate the level of the immersion liquid 1, thereby eliminating the operational risks caused by abnormal liquid levels.

[0032] Immersion liquid cooling refers to an immersion liquid-cooled energy storage system, which includes multiple tanks 3 arranged sequentially, such as 1, 2, ..., n, along a straight line. In this embodiment, the liquid level meter 4 is a prior art device, such as a level gauge, capable of measuring the liquid level 1 inside the tanks 3 and sending liquid level information to the battery management system (BMS). The BMS monitors and manages the operating status of the battery pack (cell module 2), including monitoring parameters such as voltage, current, and temperature, and balancing the charge of each cell to prevent overcharging and over-discharging, thus extending battery life. In this embodiment, the oil cooling unit includes components such as a compressor and a pump, enabling the delivery of some of the immersion liquid 1 into the tanks 3 and the extraction of some of the immersion liquid 1 from the tanks 3, creating a circulating flow of the immersion liquid 1 inside the tanks 3. This circulating immersion liquid 1 then cools the cell module 2. This application monitors the level of the immersion liquid 1 by setting up multiple liquid level gauges 4, which can keep the immersion liquid 1 inside the tank 3 within a certain range, thus achieving precise control of the immersion liquid 1 and facilitating thermal management of the battery cells.

[0033] Specifically, the level gauge can be connected to the inside of the housing 3 via fasteners, etc. It sends level information to the battery management system every three seconds. It can be connected wirelessly or via a wire harness (the wire harness passes through the housing 3 and is sealed to the housing 3 to ensure that the immersion liquid 1 does not leak).

[0034] To address the communication issue between the oil-cooled unit and housing 3, please refer to the following embodiments: Figures 1 to 2The submersible liquid-cooled energy storage system has a housing 3 with an inlet 5 and an outlet 6. An oil-cooled unit connects to the inlet 5 and outlet 6 via multiple first pipes to ensure the immersion liquid 1 circulates. The inlet 5 is located below the outlet 6, with a certain distance between them. The oil-cooled unit pumps the immersion liquid 1, which enters the housing 3 through the inlet 5 and exits through the outlet 6, returning to the oil-cooled unit. This achieves the circulation of the immersion liquid 1 within the housing 3. The flow rate of the immersion liquid 1 supplied by the oil-cooled unit is adjustable; alternatively, the immersion liquid 1 can be drawn from the housing 3 without pumping it back in. There are two first pipes: one connecting the oil-cooled unit to the inlet 5, and the other connecting the oil-cooled unit to the outlet 6.

[0035] The oil-cooled unit in this embodiment is existing technology and is therefore not shown in the figure.

[0036] To address the communication issue between the immersion liquid replenishment unit and the tank 3, in some embodiments, please refer to... Figures 1 to 2 The submersible liquid-cooled energy storage system's housing 3 also has a first replenishment port 7 and a second replenishment port 8. The submersible liquid replenishment unit is connected to the first replenishment port 7 and the second replenishment port 8 through multiple second pipes to replenish the submersible liquid 1 into the housing 3. In actual use, either the first replenishment port 7 or the second replenishment port 8 can be selected to replenish the submersible liquid 1 into the housing 3, or they can be used simultaneously to replenish the submersible liquid 1, which can improve the replenishment efficiency. The amount of submersible liquid 1 replenished can be based on the amount missing measured by the liquid level meter 4, thus keeping the submersible liquid 1 within the specified liquid level range.

[0037] Preferably, the first replenishment port 7 is set at the same height as the inlet port 5, and the second replenishment port 8 is set at the same height as the outlet port 6. The first pipe is sealed to the inlet port 5 or the outlet port 6, and the second pipe is also sealed to the first replenishment port 7 or the second replenishment port 8. Only by ensuring the sealing effect after the connection between the two can leakage be effectively prevented.

[0038] In order to replenish the submersion fluid 1 to the submersion fluid 1 at different heights, in some embodiments, please refer to Figures 1 to 2 The height of the first replenishment port 7 is lower than the height of the second replenishment port 8. When the amount of immersion liquid 1 inside the tank 3 is low, the first replenishment port 7 can be used to add immersion liquid 1. When the amount of immersion liquid 1 inside the tank 3 is high (this is relative to the amount of immersion liquid 1; in reality, the immersion liquid 1 is at a low level, so it needs to be added), the first replenishment port 7 can be used to add immersion liquid 1. In addition, the first replenishment port 7 or the second replenishment port 8 can be selected appropriately according to the actual situation.

[0039] To achieve control over the circulation and filling volume of the immersion solution 1, please refer to the following embodiments: Figures 1 to 2 Both the first and second pipes are connected to solenoid valves, which are electrically connected to and controlled by the battery management system. These solenoid valves enable connection to the battery management system, allowing control of multiple solenoid valves. This control enables control of the circulation and filling volume of the immersion fluid 1, as well as the extraction of the immersion fluid 1 from inside the housing 3. In other words, the oil-cooled unit has the function of extracting and pumping the immersion fluid 1.

[0040] Specifically, the battery management system is equipped with a control module that can control the operation of multiple solenoid valves, such as control buttons, which can be used to adjust the opening degree of the solenoid valves.

[0041] In some embodiments, please refer to Figure 1 , Figures 4 to 5 Multiple liquid level gauges 4 include a high liquid level gauge and a low liquid level gauge. The high liquid level gauge is located at the high liquid level position of the immersion liquid 1 and is used to monitor whether the liquid level of the immersion liquid 1 is higher than the position measured by the high liquid level gauge. The low liquid level gauge is located at the high liquid level position of the immersion liquid 1 and is used to monitor whether the liquid level of the immersion liquid 1 is lower than the position measured by the low liquid level gauge. When the liquid level of the immersion liquid 1 is higher than the position measured by the high liquid level gauge or lower than the position measured by the low liquid level gauge, the high liquid level gauge or the low liquid level gauge sends information to the battery management system to control the oil cooling unit to draw the immersion liquid 1 from the inside of the tank 3 or to control the immersion liquid replenishment unit to replenish the immersion liquid 1 into the inside of the tank 3. During system operation, as required or specified, the height of the immersion liquid 1 is 30mm-50mm higher than the height of the battery cell module 2. Therefore, the high liquid level meter is set at a position 50mm higher than the height of the battery cell module 2, while the low liquid level meter is set at a position 30mm higher than the height of the battery cell module 2. Thus, the current liquid level of the immersion liquid 1 can be monitored through two sets of meters (high liquid level meter and low liquid level meter), and the immersion liquid 1 can be kept within the required or set range through the oil cooling unit and the immersion liquid replenishment unit, thereby meeting the thermal management of the battery cell module 2.

[0042] Specifically, when adding immersion liquid 1 into the housing 3, when circulating the immersion liquid 1 inside the housing 3, and when extracting immersion liquid 1 from the housing 3, the corresponding solenoid valve should be opened through the battery management system.

[0043] In some embodiments, please refer to Figures 1 to 2The immersion fluid replenishment unit includes an oil pump and an oil tank. The oil tank stores immersion fluid 1. The oil pump has an extraction end and a pumping end. The extraction end is connected to the oil tank, and the pumping end is connected to either the first replenishment port 7 or the second replenishment port 8 via a second pipe. The oil pump is electrically connected to the battery management system (BMS) and its operation is controlled by the BMS. The function of the oil pump is to pump the immersion fluid 1 from the oil tank to the inside of the housing 3, thus replenishing the inside of the housing 3. The operating time, operating speed, and other parameters of the oil pump can be controlled by the BMS.

[0044] Preferably, the battery management system is equipped with a control module that can regulate the operation of the oil pump. Therefore, parameters such as the replenishment amount of the immersion fluid 1 can be controlled by operating the battery management system.

[0045] In some embodiments, please refer to Figures 1 to 2 The submersible liquid-cooled energy storage system has a positive connector 9, a negative connector 10, and a low-voltage connector 11 connected to the side of the housing 3, and an explosion-proof valve 12 connected to the top of the submersible battery pack. When the cell module 2 experiences thermal runaway, the explosion-proof valve 12 opens to release the gas generated by the runaway cell module 2, preventing damage caused by excessive gas pressure inside the housing 3.

[0046] To achieve cooling of the housing 3 and the immersion liquid 1 inside, in some embodiments, please refer to... Figure 3 The outer wall of the submerged liquid-cooled energy storage system housing 3 is tightly attached to a cooling tank 13, which is used to cool the housing 3. The cooling tank 13 is filled with coolant, and the top outer wall of the cooling tank 13 is tightly attached to the bottom surface of the housing 3. The heat of the coolant itself can be transferred to the heat of the submerged liquid 1 through the cooling tank 13 and the housing 3, thereby achieving heat exchange and cooling the submerged liquid 1.

[0047] Under normal circumstances, the temperature of the coolant should be at least 5°C lower than the temperature of the immersion fluid 1. Both the housing 3 and the cooling housing 13 are made of thermally conductive materials, which can realize the transfer or conduction of heat. That is, the coldness of the coolant can be transferred to the cooling housing 13 and the housing 3, and then it can form a heat exchange with the heat of the immersion fluid 1.

[0048] In this embodiment, the cooling box 13 is a thin, plate-like structure with a cavity. It has two openings on its side, which are used to inject and discharge coolant into the cooling box 13, respectively, allowing the coolant to circulate. The cooling box 13 and the box 3 can be fixedly connected using fasteners or similar fasteners.

[0049] In some embodiments, please refer to Figure 3The cooling box 13 is filled with coolant and is connected to a refrigeration unit. The refrigeration unit is used to circulate the coolant within the cooling box 13, allowing the coolant to exchange heat with the immersion liquid 1 inside the box 13. The refrigeration unit is connected to the cooling box 13 via pipes, enabling the coolant inside the cooling box 13 to circulate. This continuously supplies the cooling box 13 with coolant at a lower temperature, thereby achieving cyclical heat exchange with the immersion liquid 1. In this embodiment, the refrigeration unit includes a pump body, an oil tank, etc., and can be referenced from existing technologies.

[0050] The above description is only a preferred embodiment of the present utility model and is not intended to limit the present utility model. Any modifications, equivalent substitutions and improvements made within the spirit and principles of the present utility model should be included within the protection scope of the present utility model.

Claims

1. An immersion liquid cooling liquid level management system, characterized by, include: Multiple level gauges are connected to a tank in an immersion liquid-cooled energy storage system for containing immersion liquid, the level gauges being adapted to measure the level of the immersion liquid in the tank; A battery management system is electrically connected to multiple liquid level gauges, and the battery management system is used to receive liquid level information measured by multiple liquid level gauges. An oil-cooled unit is electrically connected to the battery management system and its operation is controlled by the battery management system. The oil-cooled unit is connected to the housing of the immersion liquid-cooled energy storage system and is used to circulate the immersion liquid inside the housing. The immersion liquid replenishment unit is electrically connected to the battery management system and its operation is controlled by the battery management system. The immersion liquid replenishment unit is connected to the housing of the immersion liquid-cooled energy storage system and is used to replenish the immersion liquid inside the housing.

2. The submersion liquid cooling liquid level management system of claim 1, wherein, The enclosure of the immersion liquid-cooled energy storage system has a liquid inlet and a liquid outlet. The oil-cooled unit is connected to the liquid inlet and the liquid outlet through multiple first pipes to make the immersion liquid circulate.

3. The submersion liquid cooling liquid level management system of claim 2, wherein, The enclosure of the immersion liquid-cooled energy storage system also has a first replenishment port and a second replenishment port. The immersion liquid replenishment unit is connected to the first replenishment port and the second replenishment port through multiple second pipes to replenish the immersion liquid inside the enclosure.

4. The immersion liquid-cooled level management system as described in claim 3, characterized in that, The height of the first liquid inlet is lower than the height of the second liquid inlet.

5. The submersion liquid cooling liquid level management system of claim 3, wherein, Both the first and second pipes are connected to solenoid valves, which are electrically connected to the battery management system and whose operation is controlled by the battery management system.

6. The submersion liquid cooling liquid level management system of claim 1, wherein, The plurality of liquid level gauges include a high liquid level gauge and a low liquid level gauge. The high liquid level gauge is located at the high liquid level position of the immersion liquid and is used to monitor whether the liquid level of the immersion liquid is higher than the position measured by the high liquid level gauge. The low liquid level gauge is located at the high liquid level position of the immersion liquid and is used to monitor whether the liquid level of the immersion liquid is lower than the position measured by the low liquid level gauge. When the liquid level of the immersion liquid is higher than the position measured by the high liquid level gauge or lower than the position measured by the low liquid level gauge, the high liquid level gauge or the low liquid level gauge sends information to the battery management system to control the oil cooling unit to extract immersion liquid from the tank or to control the immersion liquid replenishment unit to replenish immersion liquid into the tank.

7. The submersion liquid cooling liquid level management system of claim 3, wherein, The immersion fluid replenishment unit includes an oil pump and an oil tank. The oil tank stores immersion fluid. The oil pump has an extraction end and a pumping end. The extraction end is connected to the oil tank, and the pumping end is connected to the first replenishment port or the second replenishment port through the second pipeline. The oil pump is electrically connected to the battery management system and its operation is controlled by the battery management system.

8. The submersion liquid cooling liquid level management system of claim 1, wherein, The side of the enclosure of the immersion liquid-cooled energy storage system is connected to a positive connector, a negative connector and a low-voltage connector, and the top of the immersion battery pack is connected to an explosion-proof valve.

9. The submersion liquid cooling liquid level management system of claim 1, wherein, The outer wall of the submersible liquid-cooled energy storage system is closely attached to a cooling box, which is used to cool the system.

10. The submersion liquid cooling liquid level management system of claim 9, wherein, The cooling box is filled with cooling liquid, and a refrigerating unit is communicated with the cooling box to make the cooling liquid form a circulating flow in the cooling box, and the cooling liquid is suitable for heat exchange with the immersion liquid in the box.

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