Immersed cooling air conditioning system for energy storage

Abstract

The immersed cooling air conditioning system comprises an energy storage cabin module, a temperature control module, an oil circulation loop module, a refrigerant loop module and a sensor module, battery energy storage equipment is arranged in the energy storage cabin module, and the sensor module is used for collecting real-time temperature data of the battery energy storage equipment; the temperature control module is used for issuing an execution instruction to the oil circulation loop module according to received temperature data, and the oil circulation loop module operates according to the execution instruction, completes heat exchange with battery energy storage equipment through circular flow of oil in an internal oil tank and conveys the oil carrying heat to the refrigerant loop module; and the refrigerant loop module is used for transferring and dissipating the heat absorbed from the oil circulation loop module to the outside of the energy storage cabin module so as to realize battery cooling. The problems of uneven heat dissipation, insulation attenuation and control lag of a traditional scheme are solved, and long-term safe and efficient operation of the energy storage system can be guaranteed.

Description

Technical Field

[0001] This invention belongs to the field of air conditioning technology, specifically relating to an immersion cooling air conditioning system for energy storage. Background Technology

[0002] Energy storage devices (such as lithium battery clusters) generate a large amount of heat during high-power charging and discharging due to internal electrochemical reactions and internal resistance losses. Traditional air-cooling / water-cooling methods suffer from uneven heat dissipation, high insulation risk, and frequent local hot spots. Immersion oil cooling technology, by having insulating oil directly contact the heat-generating components, can significantly improve heat dissipation efficiency and ensure insulation safety. In existing technologies, energy storage devices generate a large amount of heat during high-power charging and discharging due to internal electrochemical reactions and internal resistance losses. Traditional air-cooling / water-cooling methods suffer from uneven heat dissipation, high insulation risk, and frequent local hot spots, and generally have the following defects: 1. Lack of temperature and humidity coupled control: Focusing only on oil temperature regulation, ignoring the impact of water content in the oil and ambient humidity on insulation performance (e.g., moisture can lead to a decrease in the dielectric strength of insulating oil); 2. Inefficient coordination of cold and heat sources: The cooling system and oil circulation loop are controlled independently, resulting in insufficient energy matching accuracy and easy oil temperature fluctuations under high loads; 3. Insufficient oil condition monitoring: Lack of real-time detection of oil aging, impurity content, and water content, posing a risk of insulation failure during long-term operation; 4. Weak redundancy protection mechanism: Failure of key components (such as oil pumps and filters) can easily lead to cooling interruption, threatening the safety of the energy storage system. Summary of the Invention

[0003] (a) Purpose of the invention The purpose of this invention is to provide an immersion cooling air conditioning system for energy storage, so as to solve the problems of uneven heat dissipation, insulation attenuation and control lag in traditional solutions, and ensure the long-term safe and efficient operation of the energy storage system.

[0004] (II) Technical Solution To address the aforementioned problems, this invention provides an immersion cooling air conditioning system for energy storage, comprising: an energy storage chamber module, a temperature control module, an oil circulation loop module, a refrigerant loop module, and a sensor module, wherein... The energy storage chamber module has a built-in battery energy storage device, and the sensor module is used to collect real-time temperature data of the battery energy storage device and transmit the temperature data to the temperature control module. The temperature control module is used to issue execution commands to the oil circulation loop module based on the received temperature data. The oil circulation loop module operates according to the execution commands, exchanging heat with the battery energy storage device through the circulation of oil in the internal oil tank, and delivering the heat-carrying oil to the refrigerant loop module. Specifically, the temperature control module's execution commands to the oil circulation loop module based on the received temperature data include: if the real-time temperature is higher than the upper limit of the temperature threshold, then initiating oil circulation; if the real-time temperature is lower than the lower limit of the temperature threshold, then stopping or reducing the intensity of oil circulation. The operation of the oil circulation loop module according to the execution commands includes: if the received execution command is to start oil circulation, then controlling the oil pump to draw cooling oil from the oil tank and delivering it to the energy storage compartment module to immerse the battery energy storage device; if the received command is to stop or reduce the intensity of oil circulation, then turning off the oil pump or reducing the pump speed via the frequency converter, closing the corresponding oil circuit valve, and switching to a low-load circulation mode. The refrigerant circuit module is used to transfer the heat absorbed from the oil circulation circuit module and dissipate it to the outside of the energy storage compartment module, thereby cooling the battery.

[0005] Preferably, the oil circulation loop module is further provided with an auxiliary heating module. The auxiliary heating module heats the oil in the oil tank and uses the circulating flow of the oil to exchange heat with the battery energy storage device, thereby heating the battery energy storage device.

[0006] Preferably, the oil circulation loop module is further provided with an oil cooler, an oil filter, an oil pump and an oil level sensor, and the oil cooler is provided with a plate heat exchanger.

[0007] Preferably, the refrigerant circuit module is further provided with an air condenser and an electronic expansion valve, and the air condenser, the electronic expansion valve and the plate heat exchanger are connected in series.

[0008] Preferably, the sensor module includes an oil temperature sensor, an oil level sensor, a temperature and humidity sensor, an oil dielectric constant sensor, a water content sensor, and a contamination sensor.

[0009] Preferably, the oil pump is a centrifugal canned pump and is equipped with a frequency converter.

[0010] Preferably, when the oil reference value is <2.8, the oil dielectric constant sensor triggers filtration.

[0011] Preferably, when the water content in the oil is detected to be >50ppm, the water content sensor activates a pre-alarm; when the water content in the oil is detected to be >80ppm, the water content sensor issues a command to remove the water.

[0012] Preferably, the system operates normally if the contamination sensor detects an ISO level ≤ 18 / 16 / 13, and triggers an oil change if it detects an ISO level > 18 / 16 / 13.

[0013] Preferably, the oil temperature sensors are distributed at the inlet and outlet of the oil tank to monitor the oil temperature at the inlet and outlet of the tank in real time.

[0014] (III) Beneficial Effects The above-mentioned technical solution of the present invention has the following beneficial technical effects: The present invention provides an immersion cooling air conditioning system for energy storage. This system can significantly improve heat dissipation efficiency and ensure insulation safety through immersion oil cooling technology. This application optimizes the high-precision temperature and humidity coordination requirements of energy storage battery modules. By having insulating oil directly contact the heat-generating components, and through the circulation of oil in the internal oil tank under the oil circulation loop module, heat exchange is completed with the battery energy storage device, ensuring that the temperature of each battery module can be removed in real time. Then, through the efficient connection between the oil circulation and the refrigerant loop module, the heat absorbed from the oil circulation loop module is transferred and dissipated to the outside of the energy storage compartment module through the refrigerant loop module, thereby achieving battery cooling. The entire heat dissipation process does not cause heat accumulation inside the compartment, which can not only stably control the battery temperature within the optimal operating range, but also avoid fluctuations in humidity inside the compartment due to heat dissipation, thus ensuring battery performance and lifespan. The immersion oil cooling technology of this application can significantly improve heat dissipation efficiency and ensure insulation safety by having insulating oil directly contact the heat-generating components. Attached Figure Description

[0015] Figure 1 This is a schematic diagram of the immersion cooling air conditioning system for energy storage according to the present invention. Detailed Implementation

[0016] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail below with reference to specific embodiments and the accompanying drawings. It should be understood that these descriptions are merely exemplary and not intended to limit the scope of the invention. Furthermore, descriptions of well-known structures and techniques are omitted in the following description to avoid unnecessarily obscuring the concept of the invention.

[0017] like Figure 1 As shown, the present invention provides an immersion cooling air conditioning system for energy storage, comprising: an energy storage chamber module 1, a temperature control module 2, an oil circulation loop module 3, a refrigerant loop module 4, and a sensor module 5, wherein the energy storage chamber module 1 has a built-in battery energy storage device (battery module). The sensor module 5 is used to collect real-time temperature data of the battery energy storage device and transmit the temperature data to the temperature control module 2. The real-time temperature data mainly includes the following five types: 1) Battery surface temperature: measured by temperature sensors (such as thermocouples or thermistors) attached to the battery casing, reflecting the temperature of the contact surface between the battery and the cooling oil; 2) Cooling oil inlet and outlet temperatures: measured in the oil circulation loop when the oil enters and leaves the battery compartment, used to calculate heat exchange efficiency and battery heat generation; 3) Average temperature of the battery pack or module: the average value of multiple sensor points, representing the overall thermal state; 4) Hot spot temperature: the temperature of the hottest area in the battery pack, usually monitored by sensors placed in locations prone to overheating (such as battery gaps or the center), used to prevent local overheating; 5) Ambient temperature: the air temperature inside the energy storage compartment, used as an auxiliary reference to ensure that the cooling system is in harmony with the environment.

[0018] The temperature control module 2 is used to issue execution commands to the oil circulation loop module 3 based on the received temperature data. The oil circulation loop module 3 operates according to the execution commands, exchanging heat with the battery energy storage device through the circulation of oil in its internal oil tank, and transporting the heat-carrying oil to the refrigerant loop module 4. Specifically, the temperature control module 2's execution commands to the oil circulation loop module based on the received temperature data include: if the real-time temperature is higher than the upper limit of the temperature threshold, oil circulation is initiated; if the real-time temperature is lower than the lower limit of the temperature threshold, the oil circulation intensity is stopped or reduced. Specifically, the temperature control module 2 acts as the "brain" of the system, issuing execution commands to the oil circulation loop module based on the received real-time temperature data and a predetermined control strategy. Specific control methods include: threshold judgment and start / stop control: setting temperature thresholds (such as the maximum allowable battery temperature or the target temperature of the cooling oil). When the real-time temperature exceeds the upper limit, oil circulation is initiated; when the temperature is lower than the lower limit, circulation is stopped or reduced to save energy. For example, if the battery temperature exceeds 40°C, the oil pump is immediately started. (1) Proportional-Integral-Derivative (PID) Control: The PID algorithm is used to dynamically adjust the oil circulation parameters. Based on the temperature error (the difference between the set temperature and the actual temperature), the control output is calculated, such as adjusting the oil pump speed or valve opening, to achieve smooth temperature regulation. (2) Adaptive Control: The cooling demand is predicted based on the temperature trend (such as the rate of temperature rise), and the oil flow rate is adjusted in advance. For example, if the temperature rises rapidly, the oil pump power is increased in advance even if the threshold is not reached.

[0019] (3) Priority control: For hot spots or critical areas, the oil flow rate in that area is increased first (controlled by zone valves) to ensure uniform cooling. (4) Safety protection: If the temperature is abnormal (e.g., exceeding a safety threshold), an alarm is triggered or an emergency mode is entered, such as running the oil circulation at full speed or activating backup cooling. The temperature control module is usually embedded with a microprocessor or PLC (Programmable Logic Controller), implementing these functions through software algorithms. Control commands are sent to the actuators (such as oil pumps and valves) of the oil circulation loop module via communication interfaces (such as CAN bus or Ethernet).

[0020] In addition, the oil circulation loop module 3 operates according to the execution command, including: if the received execution command is to start oil circulation, then the oil pump is controlled to draw cooling oil from the oil tank and deliver it to the energy storage chamber module to immerse the battery energy storage device; if the received command is to stop or reduce the oil circulation intensity, then the oil pump is turned off or the pump speed is reduced through the frequency converter, the corresponding oil circuit valve is closed, and the system switches to a low-load circulation mode. Specifically, the oil circulation loop module realizes the circulation flow of oil through mechanical and fluid components according to the execution command of the temperature control module. The specific operation process is as follows: Oil pump control: The execution command first controls the start, stop, and speed of the oil pump. For example, when cooling is required, the oil pump (which may be a centrifugal pump or a gear pump) is started, and the pump speed is adjusted by a frequency converter to change the oil flow rate. High speed corresponds to high cooling demand, and low speed corresponds to low demand.

[0021] (1) Oil circuit direction control: The oil circuit path is changed by solenoid valves or regulating valves to ensure that the oil flows evenly through the battery energy storage device. For example, the command may open a specific valve to guide the oil to the hot spot area, or switch the circulation mode (such as full circulation and partial circulation).

[0022] (2) Heat exchange process: The oil pump draws cooling oil (usually insulating mineral oil or synthetic oil) from the oil tank. The oil flows into the energy storage module, directly immersing the battery or flowing through the battery rack, absorbing the heat generated by the battery through convection and conduction. The heated oil is then transported to the heat exchanger (such as a plate heat exchanger or shell-and-tube heat exchanger) in the refrigerant loop module. • Interaction with the refrigerant loop module: In the heat exchanger, the oil transfers heat to the refrigerant (such as Freon or carbon dioxide), cools itself, and returns to the oil tank, forming a closed-loop cycle. Execution commands may coordinate the operation of the oil circulation and the refrigerant loop, such as synchronously increasing the oil flow rate and the speed of the refrigerant compressor. Auxiliary component control: This also includes maintenance commands for filters and oil tanks, such as activating auxiliary cooling or purification cycles when the oil temperature is too high. The entire operation is automated, ensuring that battery heat is efficiently transferred and ultimately dissipated to the outside of the energy storage compartment through the refrigerant loop. The oil circulation loop module is designed with reliability and energy efficiency in mind to accommodate the dynamic thermal load of the battery operation.

[0023] The refrigerant circuit module 4 is used to transfer the heat absorbed from the oil circulation circuit module and dissipate it to the outside of the energy storage module 1 to achieve battery cooling.

[0024] Each module is explained below: Energy storage module 1: Built-in battery module (immersed in insulating oil), the compartment is equipped with oil inlet and outlet and vent (connected to humidity control device).

[0025] Oil circulation loop module 3: Equipped with an oil cooler, oil filter, oil pump, and oil level sensor to achieve a fully closed-loop circulation of insulating oil. The oil cooler includes a plate heat exchanger. The oil pump is a centrifugal shielded pump equipped with a frequency converter. Preferably, the oil circulation loop module 3 also includes an auxiliary heating module. This auxiliary heating module heats the oil in the oil tank, utilizing the oil circulation flow to exchange heat with the battery energy storage device, thereby heating the battery energy storage device. An oil-side electric heating strip works in conjunction to maintain oil flow and internal temperature in low-temperature environments.

[0026] Refrigerant circuit module 4: It is equipped with an air condenser and an electronic expansion valve. The air condenser, electronic expansion valve and plate heat exchanger are connected in series. It is also equipped with a compressor, a four-way reversing valve and an evaporator on the oil cooler side to realize the transfer of cooling capacity.

[0027] Sensor Module 5 includes an oil temperature sensor, an oil level sensor, a temperature and humidity sensor, an oil dielectric constant sensor, a water content sensor, and a contamination sensor. When the oil reference value is <2.8, the oil dielectric constant sensor triggers filtration. When the detected water content in the oil is >50 ppm, the water content sensor initiates a pre-alarm; when the detected water content is >80 ppm, the water content sensor issues a command to remove the water. The contamination sensor operates normally if the detected ISO level is ≤18 / 16 / 13; if the detected ISO level is >18 / 16 / 13, it triggers an oil change. The water content sensor coordinates the oil pump speed, compressor load, and in-tank fan frequency using an adaptive fuzzy control algorithm. The oil temperature sensors are located at the inlet and outlet of the oil tank to monitor the oil temperature at the inlet and outlet in real time.

[0028] The invention will now be described in detail using a 5MWh lithium battery energy storage compartment as an application scenario.

[0029] Oil circulation power In the oil circulation circuit module: the main oil pump is a centrifugal canned pump (flow rate 50m³ / h, head 30m) and is equipped with a frequency converter (0-50Hz speed regulation). Oil filter: Dual-cylinder precision filter (5μm precision, differential pressure sensor monitors blockage status, triggers alarm and switches filter element when differential pressure > 0.15MPa); Oil tank: Horizontal stainless steel tank (volume 20m³, built-in liquid level sensor (accuracy ±2mm), temperature sensor (accuracy ±0.5℃) and electric heating belt (temperature control range 10-60℃)).

[0030] (2) Oil-cooled heat exchange In the oil circulation loop module and the refrigerant loop module: Oil cooler: Brazed plate heat exchanger (316L stainless steel), refrigerant side design pressure 4.5MPa (R410A condition), oil side design pressure 2.5MPa; Refrigerant circuit: A condenser (air-cooled standby mode) and an electronic expansion valve (control accuracy ±1℃) are connected in series with a plate heat exchanger to achieve heat exchange between the refrigerant and the insulating oil. Oil cooling circulation: The oil pump is reduced to a frequency of 30Hz (to maintain the minimum circulation volume), the compressor stops, and the oil-side electric heating belt operates at full power.

[0031] (3) Optimization of immersion oil cooling Oil flow field design: The spacing between the battery racks (50mm) and the angle of the guide fins (30°) are optimized through CFD simulation to ensure that the uniformity of the oil film flow rate on the battery surface is ≥95% and to avoid local heat exchange blind spots. Insulating oil selection: Dimethyl silicone oil (kinematic viscosity 20cSt@40℃, flash point 300℃, dielectric strength 25kV / mm) was used, and it was verified by withstand voltage test (15kV AC for 1 minute without breakdown).

[0032] (4) Cooling process: The sensor module is used to collect real-time temperature data of the battery energy storage device and transmit the temperature data to the temperature control unit. The temperature control module is used to issue execution commands to the oil circulation loop module according to the received temperature data. The oil circulation loop module operates according to the execution commands, and completes heat exchange with the battery energy storage device through the circulation of oil in the internal oil tank. The oil carrying heat is then transported to the refrigerant loop module. The refrigerant loop module is used to transfer the heat absorbed from the oil circulation loop module and dissipate it to the outside of the energy storage module to achieve battery cooling.

[0033] The sensor module can also monitor online: the dielectric constant sensor provides real-time feedback on the oil insulation status, and triggers filtering when the dielectric constant is <2.8 (new oil reference value 2.9-3.1); Moisture content sensor data drives the dehumidification rotor to start and stop (threshold logic: >50ppm pre-alarm, >80ppm forced operation). The contamination level sensor data is integrated into the oil change decision model (operation is allowed when ISO level is ≤18 / 16 / 13, and oil change is triggered when it is >18 / 16 / 13).

[0034] It should be understood that the specific embodiments described above are merely illustrative or explanatory of the principles of the invention and do not constitute a limitation thereof. Therefore, any modifications, equivalent substitutions, improvements, etc., made without departing from the spirit and scope of the invention should be included within the protection scope of the invention. Furthermore, the appended claims are intended to cover all variations and modifications falling within the scope and boundaries of the appended claims, or equivalent forms of such scope and boundaries. Obviously, the above embodiments are merely examples for clear illustration and are not intended to limit the implementation. For those skilled in the art, other variations or modifications can be made based on the above description. It is neither necessary nor possible to exhaustively list all embodiments here. However, obvious variations or modifications derived therefrom are still within the protection scope of this invention. Those skilled in the art should understand that embodiments of the invention can be provided as methods, systems, or computer program products. Therefore, the invention can take the form of a completely hardware embodiment, a completely software embodiment, or an embodiment combining software and hardware aspects. Moreover, the invention can take the form of a computer program product implemented on one or more computer-usable storage media (including but not limited to disk storage, CD-ROM, optical storage, etc.) containing computer-usable program code. These computer program instructions may also be stored in a computer-readable storage medium that can direct a computer or other programmable data processing device to function in a particular manner, such that the instructions stored in the computer-readable storage medium produce an article of manufacture including instruction means, which are implemented in a process Figure 1 One or more processes and / or boxes Figure 1 The functions specified in one or more boxes. Those skilled in the art will understand that all or part of the steps in the methods of the above embodiments can be implemented by a program instructing related hardware. The program can be stored in a computer-readable storage medium, and when executed, it includes the flows of the embodiments of the methods described above. The storage medium can be a magnetic disk, optical disk, read-only memory (ROM), or random access memory (RAM), etc.

Claims

1. An immersion cooling air conditioning system for energy storage, characterized in that, include: The system comprises an energy storage chamber module, a temperature control module, an oil circulation loop module, a refrigerant loop module, and a sensor module, wherein the energy storage chamber module integrates a battery energy storage device. The sensor module is used to collect real-time temperature data of the battery energy storage device and transmit the temperature data to the temperature control module. The temperature control module is used to issue execution commands to the oil circulation loop module based on the received temperature data. The oil circulation loop module operates according to the execution commands, exchanging heat with the battery energy storage device through the circulation of oil in the internal oil tank, and delivering the heat-carrying oil to the refrigerant loop module. Specifically, the temperature control module's execution commands to the oil circulation loop module based on the received temperature data include: if the real-time temperature is higher than the upper limit of the temperature threshold, then initiating oil circulation; if the real-time temperature is lower than the lower limit of the temperature threshold, then stopping or reducing the intensity of oil circulation. The operation of the oil circulation loop module according to the execution commands includes: if the received execution command is to start oil circulation, then controlling the oil pump to draw cooling oil from the oil tank and delivering it to the energy storage compartment module to immerse the battery energy storage device; if the received command is to stop or reduce the intensity of oil circulation, then turning off the oil pump or reducing the pump speed via the frequency converter, closing the corresponding oil circuit valve, and switching to a low-load circulation mode. The refrigerant circuit module is used to transfer the heat absorbed from the oil circulation circuit module and dissipate it to the outside of the energy storage compartment module, thereby cooling the battery.

2. The immersion cooling air conditioning system for energy storage according to claim 1, characterized in that, The oil circulation loop module is also equipped with an auxiliary heating module. The auxiliary heating module heats the oil in the oil tank and uses the circulating flow of the oil to exchange heat with the battery energy storage device, thereby heating the battery energy storage device.

3. The immersion cooling air conditioning system for energy storage according to claim 1, characterized in that, The oil circulation loop module is also equipped with an oil cooler, an oil filter, an oil pump, and an oil level sensor. The oil cooler is equipped with a plate heat exchanger.

4. The immersion cooling air conditioning system for energy storage according to claim 3, characterized in that, The refrigerant circuit module is also equipped with an air condenser and an electronic expansion valve, which are connected in series with the plate heat exchanger.

5. The immersion cooling air conditioning system for energy storage according to claim 1, characterized in that, The sensor module includes an oil temperature sensor, an oil level sensor, a temperature and humidity sensor, an oil dielectric constant sensor, a water content sensor, and a contamination level sensor.

6. The immersion cooling air conditioning system for energy storage according to claim 3, characterized in that, The oil pump is a centrifugal canned pump and is equipped with a frequency converter.

7. The immersion cooling air conditioning system for energy storage according to claim 5, characterized in that, When the oil reference value is <2.8, the oil dielectric constant sensor triggers filtration.

8. The immersion cooling air conditioning system for energy storage according to claim 5, characterized in that, When the water content in the oil is detected to be greater than 50 ppm, the water content sensor will activate a pre-alarm. When the water content in the oil is detected to be greater than 80 ppm, the water content sensor will issue a command to remove the water.

9. The immersion cooling air conditioning system for energy storage according to claim 5, characterized in that, If the contamination sensor detects an ISO level ≤ 18 / 16 / 13, it will operate normally; if it detects an ISO level > 18 / 16 / 13, it will trigger an oil change.

10. The immersion cooling air conditioning system for energy storage according to claim 5, characterized in that, The oil temperature sensors are located at the inlet and outlet of the oil tank to monitor the oil temperature at the inlet and outlet of the tank in real time.

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