Direct cooling device of energy storage system and heat management system

Abstract

The utility model discloses a direct cooling device and a heat management system of an energy storage system, the energy storage system comprises an energy storage component and a heat transfer component, the heat transfer component is provided with a fluid channel, the heat transfer component can be connected with the direct cooling device through a first pipeline and a second pipeline, the direct cooling device comprises a heat supply module and a valve assembly, the heat supply module comprises a gas compressor, a gas-liquid separator, a first heat exchanger, a heat regenerator and a fluid storage tank, the heat regenerator is provided with a first fluid passage and a second fluid passage, and the heat management system comprises a cooling passage and a cooling backflow passage. The cooling passage, the fluid channel and the cooling backflow passage form a cooling circulation passage; the detection control module comprises a controller and a pressure sensor which is arranged in a pipeline and is in electrical connection or signal connection with the controller, the heat supply module is connected with the controller and is controlled by the controller, and the heat management system is simple in structure and high in energy efficiency.

Description

Technical Field

[0001] The utility model relates to a direct cooling device for an energy storage system and a thermal management system for an energy storage system. Background Art

[0002] An energy storage system is a device or system capable of storing energy. It can store excess energy and use it when needed. Energy storage systems are usually used to improve energy utilization efficiency, reduce energy waste, and improve power grid stability. Energy storage systems can include devices or technologies such as batteries, supercapacitors, flywheels, and hydraulic systems, among which batteries are one of the most commonly used energy storage methods. Energy storage systems can be used in various application scenarios, such as power grid peak shaving, renewable energy grid connection, electric vehicle charging, and home energy storage.

[0003] During the operation of an energy storage system, excessive temperature can cause faults in the energy storage system. Therefore, it is necessary to set up a thermal management system including a refrigeration mechanism to manage the heat of the energy storage system. The design of the thermal management system needs to consider various factors, including the heating power of the battery, the thermal insulation design of the container, and the thermal management control strategy. Thermal management is crucial for an energy storage system. It can prevent the battery from overheating, extend the battery life, and reduce safety risks. With the development of the energy storage industry, thermal management technologies are also constantly being studied and improved to meet the requirements of higher energy density, more efficient and balanced heat dissipation, higher reliability and stability, lower energy consumption, and lower cost.

[0004] The existing thermal management systems for energy storage systems generally have deficiencies such as limited overall energy efficiency, complex system structure, and high cost. For the refrigeration mechanism, the commonly used cooling methods are air cooling, liquid cooling, and direct cooling. The air cooling method has deficiencies such as low heat transfer efficiency and uneven battery core temperatures due to uneven wind field distribution. The liquid cooling method requires two heat exchanges, with low heat transfer efficiency and problems of uneven surface temperatures of the cold plates of the battery box. In the prior art, most thermal management systems using the direct cooling method have high configuration requirements for PTC, difficult control, poor stability, and cannot effectively and strictly control the uniformity of the cold plate temperature. Summary of the Utility Model

[0005] The purpose of the utility model is to provide a new direct cooling device for an energy storage system.

[0006] To achieve the above object, the technical solution adopted by the present utility model is as follows: A direct cooling device for an energy storage system, the energy storage system includes an energy storage component and a heat transfer component, the heat transfer component has a first port, a second port and a fluid channel connecting the first port and the second port, the first port and the second port can be connected to the direct cooling device through a first pipeline and a second pipeline, the direct cooling device includes a heat supply module, a valve assembly, and a detection and control module, the heat supply module includes a gas compressor, a gas-liquid separator, a first heat exchanger, a regenerator, and a fluid storage tank, the regenerator has a first fluid passage and a second fluid passage that are independent of each other but can exchange heat with each other,

[0007] The outlet of the gas compressor, the first heat exchanger, the fluid storage tank, the first fluid passage of the regenerator, and the first pipeline are sequentially connected through pipelines to form a cooling passage for supplying a refrigerant with a preset temperature to the heat transfer component, wherein a first electronic expansion valve is provided on the pipeline between the first fluid passage of the regenerator and the first pipeline; the second pipeline, the second fluid passage of the regenerator, the gas-liquid separator, and the inlet of the gas compressor are sequentially connected through pipelines to form a cooling return passage for recovering the refrigerant, and the cooling passage, the fluid channel in the heat transfer component, and the cooling return passage form a cooling circulation passage;

[0008] The direct cooling device may further optionally include a refrigerant in a gas-liquid two-phase equilibrium state at the preset temperature;

[0009] The detection and control module includes a controller, and a pressure sensor disposed in the pipeline included in the heat supply module and electrically connected or signal-connected to the controller, and the heat supply module is connected to the controller and controlled by the controller.

[0010] In some embodiments, the pressure sensor includes a first pressure sensor disposed at the inlet of the gas compressor and a second pressure sensor disposed at the outlet of the gas compressor; and / or, the controller is electrically or communicatively connected to the gas compressor, and the controller is configured to be able to adjust the rotation speed of the gas compressor according to the detection value of the pressure sensor; and / or, the controller is electrically or communicatively connected to the valve assembly, and the controller is configured to control the opening and closing and / or the opening degree of the valve according to a preset program.

[0011] In some embodiments, the preset temperature is above 15 degrees Celsius and below 25 degrees Celsius; and / or, the refrigerant is R134a, R1234yf, R410A, R513A, R513B or R454B.

[0012] In some embodiments, the fluid channel includes a plurality of first channels arranged in parallel along a first direction, and second channels connected between the first channels, such that the pressure difference when the fluid flows from the first port through the fluid channel to the second port is less than a preset value; and / or, the projection of the energy storage component on the heat transfer component falls within the distribution range of the fluid channel.

[0013] In some embodiments, along a second direction perpendicular to the first direction, the first port and the second port are respectively located on different sides of the heat transfer component. Along the second direction, the fluid channel extends from the first port to the second port along an S-shaped extension trajectory.

[0014] In some embodiments, along a second direction perpendicular to the first direction, the first port and the second port are located on the same side of the heat transfer component. The fluid channel extends from the first port along an S-shaped extension trajectory to the other side of the heat transfer component along the second direction, and then extends back to the second port along an S-shaped extension trajectory from the side away from the first port along the second direction.

[0015] In some embodiments, along a second direction perpendicular to the first direction, the outermost one of the first channels is connected to the first port, and any other one of the first channels is connected to the second port. There are two second channels. Along the first direction, on the side away from the first port, one of the second channels connects the ends of all the first channels together. On the side close to the first port, the other second channel connects the ends of all the first channels except the one connected to the first port together.

[0016] In some embodiments, along a second direction perpendicular to the first direction, the first channels and the second channels are connected to form a plurality of rectangular loops distributed at intervals. The fluid channel further includes a third channel that serially connects the plurality of rectangular loops. One free end of the third channel is connected to the first port, and the other free end of the third channel is connected to the second port.

[0017] In some embodiments, along a second direction perpendicular to the first direction, the first channels and the second channels are connected to form a plurality of rectangular loops distributed at intervals. The fluid channel includes a fourth channel connected between the two outermost rectangular loops in the second direction. The first port is provided on the fourth channel. Adjacent two rectangular loops are connected by a fifth channel, and along the second direction, the fifth channels are alternately distributed on different sides of the rectangular loops along the first direction. The second port is provided on the fifth channel.

[0018] In some embodiments, the fluid channel is spiral.

[0019] In some embodiments, the outlet of the gas compressor, the first heat exchanger, the fluid storage tank, the first fluid passage of the regenerator, the first electronic expansion valve, the gas-liquid separator, and the inlet of the gas compressor are sequentially connected through pipelines to form a defrosting circulation path.

[0020] In some embodiments, the valve assembly includes a first solenoid valve disposed on the pipeline between the gas compressor and the first heat exchanger, a second solenoid valve disposed on the pipeline between the second pipeline and the second fluid passage of the regenerator, a third solenoid valve disposed on the pipeline between the first electronic expansion valve and the gas-liquid separator, and stop valves disposed on the first pipeline and the second pipeline. The controller is electrically connected to the valve assembly, and the controller is configured to be able to control the opening or closing of the solenoid valves.

[0021] In some embodiments, the first solenoid valve and the second solenoid valve are opened, the third solenoid valve is closed, and the cooling circulation path is opened; the first solenoid valve and the third solenoid valve are opened, the second solenoid valve is closed, and the defrosting circulation path is opened.

[0022] In some embodiments, the direct cooling device includes temperature sensors. Among them, the temperature sensors include a first temperature sensor disposed on the pipeline between the first fluid passage of the regenerator and the first electronic expansion valve, a second temperature sensor disposed on the pipeline between the first fluid passage of the regenerator and the fluid storage tank, a third temperature sensor disposed on the pipeline between the second fluid passage of the regenerator and the second pipeline, and a fourth temperature sensor disposed at the inlet of the gas compressor. The controller is electrically connected or communicatively connected to the temperature sensors. The controller is electrically connected to the first electronic expansion valve, and the controller is configured to be able to acquire the data of the temperature sensors and adjust the opening degree of the first electronic expansion valve according to the acquired data.

[0023] The object of the present utility model is to provide a new thermal management system for an energy storage system.

[0024] To achieve the above object, the technical solution adopted by the present utility model is: a thermal management system for an energy storage system, including the direct cooling device of the above-mentioned energy storage system and multiple groups of heat transfer components, and each of the heat transfer components is the same as the above-mentioned heat transfer components.

[0025] In some embodiments, the multiple groups of heat transfer components are arranged in parallel, and a liquid distributor is provided on the first pipeline and the second pipeline. The liquid distributor is used to evenly distribute the refrigerant to multiple groups of the heat transfer components.

[0026] In some embodiments, multiple sets of parallel branches are formed between the first pipeline and the second pipeline, and a set of the heat transfer components is provided on each parallel branch, and a liquid separation valve for controlling the refrigerant flow rate is provided on each parallel branch.

[0027] Due to the application of the above technical solution, the present utility model has the following advantages compared with the prior art: The thermal management system of the energy storage system of the present utility model cools the energy storage system in a direct cooling manner, and the refrigerant directly exchanges heat with the energy storage components, with higher heat exchange efficiency. At the same time, the thermal management system has a simple structure and does not require a complex PLC control, and controls the stability and uniformity of the temperature by detecting the pressure. Compared with the prior art, the present utility model can be used for the thermal management of high energy density energy storage boxes and can effectively and reliably control the temperature uniformity of the energy storage system. At the same time, it has advantages in at least one aspect such as cost, energy efficiency, and stability compared with the existing thermal management systems. Description of the Drawings

[0028] Attached Figure 1 is a schematic diagram of the thermal management system of Embodiment 1 of the present utility model in the cooling mode;

[0029] Attached Figure 2 is a schematic diagram of the second setting method of the heat transfer component of the present utility model;

[0030] Attached Figure 3 is a schematic diagram of the third setting method of the heat transfer component of the present utility model;

[0031] Attached Figure 4 is a schematic diagram of the first setting method of the fluid channel of the present utility model;

[0032] Attached Figure 5 is a schematic diagram of the second setting method of the fluid channel of the present utility model;

[0033] Attached Figure 6 is a schematic diagram of the third setting method of the fluid channel of the present utility model;

[0034] Attached Figure 7 is a schematic diagram of the fourth setting method of the fluid channel of the present utility model;

[0035] Attached Figure 8 is a schematic diagram of the fifth setting method of the fluid channel of the present utility model;

[0036] Attached Figure 9 is a schematic diagram of the sixth setting method of the fluid channel of the present utility model;

[0037] Attached Figure 10Schematic diagram of the overall structure of Embodiment 2 of the present utility model;

[0038] Appendix Figure 11 Schematic diagram of the overall control structure of the refrigeration control system of Embodiment 2 of the present utility model;

[0039] Appendix Figure 12 Schematic diagram of the overall control structure of the defrosting system of Embodiment 2 of the present utility model;

[0040] Appendix Figure 13 Temperature distribution diagram of the refrigeration operation system of Embodiment 2 of the present utility model;

[0041] Appendix Figure 14 Comparison diagram of the inlet and outlet temperatures of the liquid cooling plate and the inlet and outlet temperatures of the direct cooling plate of Embodiment 2 of the present utility model;

[0042] Appendix Figure 15 Schematic diagram of the efficiency improvement - reverse Carnot cycle energy efficiency comparison of Embodiment 2 of the present utility model. Detailed implementation mode

[0043] The technical solutions of the present utility model will be elaborated in detail below in conjunction with the accompanying drawings and specific embodiments, so that the advantages and features of the present utility model are more easily understood by those skilled in the art. Obviously, the described embodiments of the present application are only a part of the embodiments of the present application, rather than all of the embodiments. All other embodiments obtained by those skilled in the art without creative efforts based on the embodiments in the present application belong to the scope of protection of the present application.

[0044] Embodiment 1

[0045] An energy storage system includes an energy storage box and a heat transfer component 200 for heat exchange of the energy storage box. During the working process, the temperature of the energy storage box will rise. To ensure the normal operation of the energy storage box and guarantee its working efficiency, the energy storage box can be cooled through the heat transfer component 200. In this embodiment, the energy storage box includes an energy storage component 100, and the heat transfer component 200 is in contact with the energy storage component 100 for heat exchange. Specifically, in this embodiment, the energy storage component 100 is an energy storage battery pack.

[0046] See Figure 1A thermal management system of an energy storage system as shown is used to control and manage the temperature of the energy storage system. The thermal management system includes the above-mentioned heat transfer component 200, which has a first port 210 and a second port 220, and a fluid channel 230 connecting the first port 210 and the second port 220. The thermal management system further includes a direct cooling device. The first port 210 and the second port 220 can be connected to the direct cooling device through a first pipeline 910 and a second pipeline 920. The direct cooling device includes a heat supply module, a valve assembly, and a detection and control module. The heat supply module can introduce refrigerants at different temperatures into the heat transfer component 200, and the refrigerant introduced into the heat transfer component 200 directly exchanges heat with the energy storage component 100, with higher heat exchange efficiency.

[0047] The heat supply module includes a gas compressor 300, a gas-liquid separator 400, a heat exchanger group 500, a regenerator 600, a fluid storage tank 700, and a detection and control module. Among them, the gas compressor 300 is used to pressurize the refrigerant and discharge the refrigerant in a high-temperature and high-pressure gas state. The gas-liquid separator 400 is used to separate gas and liquid. The heat exchanger group 500 is used to perform heat exchange on the refrigerant before it is introduced into the heat transfer component 200 and after it is discharged from the heat transfer component 200, and it includes a first heat exchanger 510. The regenerator 600 is also used to perform heat exchange on the refrigerant, and it has a first fluid passage 610 and a second fluid passage 620 that are independent of each other but can exchange heat with each other. The system has different requirements for the refrigerant under different operating modes, and the fluid storage tank 700 can play a role in temporarily storing the refrigerant.

[0048] See Figure 1 As shown, the gas compressor 300, the first heat exchanger 510, the fluid storage tank 700, the first fluid passage 610 of the regenerator 600, and the first pipeline 910 are sequentially connected through pipelines to form a cooling passage for supplying the refrigerant with a preset temperature to the heat transfer component 200. Specifically, the outlet of the gas compressor 300 is connected to the first heat exchanger 510 through a pipeline. Among them, a first electronic expansion valve 810 is provided on the pipeline between the first fluid passage 610 of the regenerator 600 and the first pipeline 910. The first electronic expansion valve 810 can regulate the pressure of the refrigerant introduced into the heat transfer component 200, and the first electronic expansion valve 810 can cooperate with the gas compressor 300 to adjust the flow rate of the refrigerant introduced into the heat transfer component 200. The second pipeline 920, the second fluid passage 620 of the regenerator 600, the gas-liquid separator 400, and the gas compressor 300 are sequentially connected through pipelines to form a cooling return passage for recovering the refrigerant. Specifically, the gas-liquid separator 400 is connected to the inlet of the gas compressor 300 through a pipeline.

[0049] The cooling passage, the fluid passage 230 in the heat transfer component 200, and the cooling return passage constitute a cooling circulation passage. When the temperature of the energy storage component 100 is higher than the first temperature, the refrigerant circulates in the cooling circulation passage and continuously cools the energy storage component 100, and the thermal management system turns on the cooling mode. In a preferred embodiment, the first temperature is 15 to 35 degrees Celsius.

[0050] In the cooling mode, the refrigerant discharged by the gas compressor 300 flows through the first heat exchanger 510, the fluid storage tank 700, the first fluid passage 610 of the regenerator 600, and the first pipeline 910 in sequence, and enters the fluid passage 230 of the heat transfer component 200 from the first port 210. After the refrigerant in the fluid passage 230 exchanges heat with the energy storage component 100, it flows out from the second port 220, and then flows through the second pipeline 920, the second fluid passage 620 of the regenerator 600 and the gas-liquid separator 400 in sequence. Finally, the refrigerant flows back into the gas compressor 300, and at this time, one cycle is completed and the next cycle starts. In this mode, the first port 210 is the inlet of the heat transfer component 200, and the second port 220 is the outlet of the heat transfer component 200.

[0051] In this embodiment, the thermal management system includes a refrigerant in a gas-liquid two-phase equilibrium state at a preset temperature. In some preferred embodiments, the preset temperature is above 15 degrees Celsius and below 25 degrees Celsius. In some embodiments, the thermal management system does not include a refrigerant.

[0052] In this embodiment, the fluid passage 230 has such a shape that the pressure difference when the fluid flows from the first port 210 through the fluid passage to the second port 220 is less than a preset value, so as to be able to control the pressure drop between the first port 210 and the second port 220. After the refrigerant is introduced into the fluid passage 230 in this way, in the state of gas-liquid two-phase equilibrium, and when the pressure drop difference between the first port 210 and the second port 220 is controlled within a preset range, the temperature difference between the first port 210 and the second port 220 can be controlled, so that the temperature of the refrigerant in the fluid passage 230 is uniform, and the heat exchange effect between the refrigerant and the energy storage component 100 is better.

[0053] The detection and control module includes a controller and a pressure sensor disposed in the pipeline included in the heat supply module and electrically connected or signal-connected to the controller. The heat supply module is connected to the controller and controlled by the controller.

[0054] In this embodiment, the refrigerant is preferably selected from R134a, R1234yf, R410A, R513A, R513B, and R454B. When R134a is used as the refrigerant, the heat transfer component 200 with a pressure difference between the first port 210 and the second port 220 less than 19 kPa is selected; when R1234yf is used as the refrigerant, the heat transfer component 200 with a pressure difference between the first port 210 and the second port 220 less than 19 kPa is selected; when R410A is used as the refrigerant, the heat transfer component 200 with a pressure difference between the first port 210 and the second port 220 less than 20 kPa is selected; when R513A is used as the refrigerant, the heat transfer component 200 with a pressure difference between the first port 210 and the second port 220 less than 20 kPa is selected; when R513B is used as the refrigerant, the heat transfer component 200 with a pressure difference between the first port 210 and the second port 220 less than 43 kPa is selected; when R454B is used as the refrigerant, the heat transfer component 200 with a pressure difference between the first port 210 and the second port 220 less than 40 kPa is selected.

[0055] In this embodiment, in the cooling cycle path, the refrigerant discharged by the gas compressor 300 is in a high-temperature and high-pressure gas state. In the pipeline between the gas compressor 300 and the first heat exchanger 510, the refrigerant is still in a high-temperature and high-pressure gas state. The first heat exchanger 510 cools the flowing refrigerant, so that after the cooling treatment, in the pipeline between the first heat exchanger 510 and the first fluid path 610 of the regenerator 600, the refrigerant is in a medium-temperature and high-pressure liquid state. The refrigerant flowing through the first fluid path 610 of the regenerator 600 will be further cooled, so that in the pipeline between the first fluid path 610 of the regenerator 600 and the first electronic expansion valve 810, the refrigerant is in a low-temperature and high-pressure liquid state. The first electronic expansion valve 810 releases the pressure of the refrigerant, so that the refrigerant flowing through the first electronic expansion valve 810 is converted into a low-temperature and low-pressure gas-liquid two-phase state, and the refrigerant in the first pipeline 910 and the fluid channel 230 is in a low-temperature and low-pressure gas-liquid two-phase equilibrium state. The refrigerant flowing out of the second port 220 is still in a liquid-carrying state. Then the refrigerant flows through the second fluid path 620 of the regenerator 600, and the medium-temperature and high-pressure refrigerant in the first fluid path 610 exchanges heat with the refrigerant in the second fluid path 620, so that all the refrigerant in the second fluid path 620 is converted into a gaseous state. The gas-liquid separator 400 provided between the second fluid path 620 and the gas compressor 300 further separates the liquid refrigerant in the pipeline, improving the safety performance. In the pipeline between the gas-liquid separator 400 and the gas compressor 300, the refrigerant is in a low-temperature and low-pressure gas state. This ensures that the refrigerant introduced into the gas compressor 300 is in a fully gaseous state, guaranteeing the normal operation of the gas compressor 300. Then the gas compressor 300 pressurizes the introduced refrigerant and discharges the high-temperature and high-pressure gaseous refrigerant, thus starting the second cycle.

[0056] The thermal management system of the energy storage system in this embodiment also has a defrosting mode for removing the frost condensed on the surface of the first heat exchanger 510, and the cooling mode can be directly used for defrosting. Specifically, in the refrigeration mode, the first heat exchanger 510 exchanges heat with the flowing refrigerant through the circulating air, which includes a fan 511 for circulating the air. In the defrosting mode, the fan 511 is turned off, and the refrigerant directly exchanges heat with the frost attached to the first heat exchanger 510 and plays a role in removing the frost during the heat exchange process.

[0057] In the thermal management system, the gas compressor 300, the first heat exchanger 510, the fluid storage tank 700, the first fluid passage 610 of the regenerator 600, the first electronic expansion valve 810, the gas-liquid separator 400, and the gas compressor 300 are sequentially connected through pipelines to form a defrosting cycle path. The refrigerant circulates in the defrosting cycle path, which can eliminate the frost condensed on the surface of the first heat exchanger. Specifically, in the defrosting mode, the high-temperature and high-pressure gaseous refrigerant discharged by the gas compressor 300 flows through the first heat exchanger 510 to eliminate the attached frost, and then the refrigerant returns to the gas compressor 300 to complete a cycle.

[0058] In this embodiment, stop valves 830 are provided on both the first pipeline 910 and the second pipeline 920. Before connecting the heat supply module and the heat transfer component 200, the two stop valves 830 are in the closed state. After connecting the heat supply module and the heat transfer component 200 through the first pipeline 910 and the second pipeline 920, the stop valves 830 are opened.

[0059] In this embodiment, the controller can control the opening, closing, and opening degree of the valves included in the heat supply module according to a preset program, so that the heat supply module operates in different modes. Specifically, the thermal management system of the energy storage system includes a valve assembly for controlling the opening and closing of the pipeline. The valve assembly includes a first solenoid valve 841 provided on the pipeline between the outlet of the gas compressor 300 and the first heat exchanger 510, a second solenoid valve 842 provided on the pipeline between the second pipeline 920 and the second fluid passage 620 of the regenerator 600, and a third solenoid valve 843 provided on the pipeline between the first electronic expansion valve 810 and the gas-liquid separator 400.

[0060] The controller is electrically connected to the valve assembly and can control the opening or closing of the solenoid valve. When using the thermal management system to manage the energy storage system, when the temperature of the energy storage component 100 is higher than the first temperature, the controller controls the first solenoid valve 841 and the second solenoid valve 842 to open, and controls the third solenoid valve 843 to close, then the cooling cycle path is connected, and the cooling mode is started. When the controller controls the first solenoid valve 841 and the third solenoid valve 843 to open and the second solenoid valve 842 to close, the defrosting cycle path is connected, and the defrosting mode is started.

[0061] In this embodiment, the pressure sensors include a first pressure sensor provided at the inlet of the gas compressor 300 and a second pressure sensor provided at the outlet of the gas compressor 300. The controller is electrically or communicatively connected to the gas compressor 300 and the valves included in the heat supply module, and the controller can adjust the rotation speed of the gas compressor according to the detected values of the pressure sensors. Specifically, the first pressure sensor can obtain the pressure value P1 at the inlet of the gas compressor 300, and the second pressure sensor can obtain the pressure value P2 at the outlet of the gas compressor 300.

[0062] In the cooling mode, compare the saturation temperature Tp1 of the refrigerant at the P1 pressure value with a preset temperature:

[0063] When Tp1 is lower than the preset temperature range, reduce the rotational speed of the gas compressor;

[0064] When Tp1 is higher than the preset temperature range, increase the rotational speed of the gas compressor.

[0065] In this embodiment, the thermal management system of the energy storage system includes temperature sensors. The temperature sensors include a first temperature sensor disposed on the pipeline between the first fluid passage 610 of the regenerator 600 and the first electronic expansion valve 810, a second temperature sensor disposed on the pipeline between the first fluid passage 610 of the regenerator 600 and the fluid storage tank 700, a third temperature sensor disposed on the pipeline between the second fluid passage 620 of the regenerator 600 and the second pipeline 920, and a fourth temperature sensor disposed at the inlet of the gas compressor 300. Among them, the first temperature sensor is used to obtain the temperature T1 at the outlet of the first fluid passage 610 of the regenerator 600, the second temperature sensor is used to obtain the temperature T2 at the inlet of the first fluid passage 610 of the regenerator 600, the third temperature sensor is used to obtain the temperature T3 at the inlet of the second fluid passage 620 of the regenerator 600, and the fourth temperature sensor is used to obtain the temperature T4 at the inlet of the gas compressor 300.

[0066] In this embodiment, the controller is electrically connected or communicatively connected to the temperature sensors, and the controller is also connected to the first electronic expansion valve 810. The controller can acquire and analyze the data of the temperature sensors and the pressure sensors and adjust the opening degree of the first electronic expansion valve 810 according to the analysis results, so as to adjust the temperature or state of the refrigerant, ensure that the refrigerant in the heat transfer component 200 is in a gas-liquid two-phase equilibrium state, and at the same time ensure that all the refrigerant entering the gas compressor 300 is in a gaseous state.

[0067] Specifically, in the cooling mode:

[0068] When T2 - T1 > Ta, the first electronic expansion valve is closed smaller;

[0069] When T3 - Tp1 > Tb, the first electronic expansion valve is opened larger,

[0070] Otherwise, when T4 - Tp1 > (Tc + db), the first electronic expansion valve is opened larger;

[0071] When T4 - Tp1 < (Tc - db), the first electronic expansion valve is closed smaller;

[0072] When (Tc - db)°C ≤ T4 - Tp1 ≤ (Tc + db), the first electronic expansion valve remains unchanged;

[0073] Among them, Tp1 is the saturation temperature corresponding to the pressure value P1, Ta, Tb, and Tc are predetermined temperature thresholds, and db is an empirical parameter related to the number of control dead zones in the system.

[0074] In this embodiment, the projection of the energy storage component 100 on the heat transfer component 200 is located within the distribution range of the fluid channel 230, so as to ensure that the heat transfer component 200 conducts comprehensive heat exchange with the energy storage component 100, avoiding local areas of the energy storage component 100 not being heat-exchanged. In this embodiment, by setting the fluid channel 230, it is possible to ensure that the pressure difference between the first port 210 and the second port 220 is less than a preset value, so that the pressure drop between the first port 210 and the second port 220 is within a preset range. Specifically, the fluid channel 230 includes a plurality of first channels 231 arranged in parallel along the first direction, and second channels 232 connected between the first channels 231.

[0075] Figure 4 The first setting method of the fluid channel 230 is shown. In this setting method, along the second direction, the first port 210 and the second port 220 are respectively arranged on two different sides of the heat transfer component 200. The second direction is perpendicular to the first direction. And in this setting method, along the first direction, the first port 210 and the second port 220 are located on the same side of the heat transfer component 200. In other setting methods, the first port 210 and the second port 220 can be respectively arranged on different sides in the first direction. The second channel 232 is in a semi-circular arc shape and is connected between the ends of two adjacent first channels 231. The fluid channel 230 extends from the first port 210 to the second port 220 along an S-shaped extension trajectory.

[0076] Figure 5 The second setting method of the fluid channel 230 is shown. In this setting method, along the second direction, the first port 210 and the second port 220 are arranged on the same side of the heat transfer component 200, and along the first direction, the first port 210 and the second port 220 are also arranged on the same side of the heat transfer component 200. The second channel 232 is also in a semi-circular arc shape. The fluid channel 230 extends from the first port 210 along an S-shaped extension trajectory to the other side of the heat transfer component 200 along the second direction, and then extends from the side far from the first port 210 along an S-shaped extension trajectory in the reverse direction to the second port 220 along the second direction.

[0077] Figure 6 The third setting method of the fluid channel 230 is shown. In this setting method, the fluid channel 230 is in a spiral shape.

[0078] In the above three ways of arranging the fluid channels 230, the refrigerant flows from one end of the fluid channel 230 to the other end without any diversion in the middle. In the following several ways of arranging, the refrigerant will be diverted within the fluid channel 230.

[0079] Figure 7 The fourth way of arranging the fluid channel 230 is shown. In this way of arranging, along the second direction, one of the outermost first channels 231 is connected to the first port 210, and any other first channel 231 is connected to the second port 220. In this way of arranging, the two first channels 231 connected to the first port 210 and the second port 220 are adjacent. The second channels 232 extend along the second direction and there are two of them. Along the first direction, on the side away from the first port 210, one of the second channels 232 connects the ends of all the first channels 231 together. On the side close to the first port 210, the other second channel 232 connects the ends of all the first channels 231 except the first channel 231 connected to the first port 210 together.

[0080] Figure 8 The fifth way of arranging the fluid channel 230 is shown. In this way of arranging, the first channels 231 are connected to the second channels 232 to form a plurality of rectangular loops spaced along the second direction. The fluid channel 230 further includes a third channel 233 that serially connects the plurality of rectangular loops. One free end of the third channel 233 is connected to the first port 210, and the other free end of the third channel 233 is connected to the second port 220.

[0081] Figure 9 The sixth way of arranging the fluid channel 230 is shown. In this way of arranging, the first channels 231 are connected to the second channels 232 to form a plurality of rectangular loops spaced along the second direction. The fluid channel 230 includes a fourth channel 234 connected between the two outermost rectangular loops in the second direction. The first port 210 is arranged on the fourth channel 234. Adjacent two rectangular loops are connected by a fifth channel 235, and along the second direction, the fifth channels 235 are alternately distributed on the different sides of the rectangular loops along the first direction. The second port 220 is arranged on the fifth channel 235. In this way, the fluid flows in two different directions at the first port 210 or the second port 220, or converges from two different directions.

[0082] In this embodiment, the heat transfer component 200 includes multiple groups arranged in parallel. A liquid distributor 930 is provided on the first pipe 910 and the second pipe 920. The liquid distributor 930 is used to evenly distribute the refrigerant into multiple groups of heat transfer components 200, so as to be able to heat or cool multiple groups of energy storage components 100 synchronously. In this way, heat exchange can be carried out on multiple groups of energy storage components 100 at the same time, and the liquid distributor 930 can evenly distribute the refrigerant, making the temperatures of the branches through which the refrigerant flows into each group of heat transfer components 200 similar, ensuring that the heat exchange effects of multiple groups of heat transfer components 200 are the same.

[0083] In other embodiments, multiple groups of heat transfer components 200 are also provided. Multiple parallel branches 940 arranged in parallel are formed between the first pipe 910 and the second pipe 920. One group of heat transfer components 200 is provided on each parallel branch 940, and a liquid separation valve 850 for controlling the refrigerant flow rate is provided on each parallel branch 940. In some embodiments, as shown in Figure 2 shown, the liquid separation valve 850 is an electronic expansion valve. A port temperature sensor T6 is also provided on each parallel branch 940. Specifically, a port temperature sensor T6 is provided on each side of the heat transfer component 200. The electronic expansion valve is electrically connected or signal-connected to the port temperature sensor T6. In the cooling mode, the electronic expansion valve adjusts the opening degree according to the value of the port temperature sensor T6 near the second port 220 side; in the heating mode, in the cooling mode, the electronic expansion valve adjusts the opening degree according to the value of the port temperature sensor T6 near the first port 210 side. In other embodiments, as shown in Figure 3 shown, the liquid separation valve 850 is a throttler, and the throttler is used to control the refrigerant flow rate in each parallel branch and control the refrigerant flow rate flowing into each heat transfer component 200.

[0084] In some preferred embodiments, a filter is provided on the pipeline between the first fluid passage 610 of the regenerator 600 and the first pipe 910 for filtering the refrigerant to improve the safety of the system.

[0085] In some embodiments, multiple groups of heat transfer components 200 arranged in parallel form a heat transfer module, and multiple groups of heat transfer modules are arranged in parallel in the thermal management system, further increasing the number of energy storage components 100 that the thermal management system can heat or cool synchronously.

[0086] Embodiment 2

[0087] As Figure 10 shown, Embodiment 2 of the present utility model provides an energy storage direct cooling system, including a refrigeration control system and a defrosting system, wherein the temperature of the energy storage system is controlled and adjusted through the refrigeration control system, and the frost is removed through the defrosting system.

[0088] As Figure 11As shown in the figure, the process of cooling the energy storage system using the refrigeration control system is as follows: The refrigerant is passed into the oil separator 2 through the compressor 1. The oil in the refrigerant is separated by the oil separator 2. After flowing through the oil separator 2, the refrigerant enters the outdoor heat exchanger 3, and then enters the liquid receiver 4 through the heating throttle valve 31, and then enters the refrigeration throttle valve 6 through the regenerator 5.

[0089] After passing through the refrigeration throttle valve 6, it enters the refrigeration distributor 61. The refrigeration distributor 61 evenly distributes the refrigerant to each branch cold plate 62 where the energy storage battery is located, and at the same time controls the pressure drop of each refrigerant circuit so that the pressure drop forms a refrigerant temperature change < 0.5°C. Subsequently, the refrigerant passes through the heating distributor 7 and returns to the regenerator 8, and then returns to the gas-liquid separator 9 to complete one cycle, and undergoes secondary cycle refrigeration through the compressor 1. In the refrigeration control system, there are also a primary refrigerant circuit, a secondary refrigerant circuit, and a tertiary refrigerant circuit.

[0090] The devices passed through by the entire system are as follows:

[0091] Compressor → Oil separator → Outdoor heat exchanger + Outdoor heat exchanger → Heating throttle valve + Check valve → Liquid receiver → Regenerator → Refrigeration throttle valve → Refrigeration distributor → Cold plate → Heating distributor → Refrigeration valve → Regenerator → Gas-liquid separator → Compressor

[0092] Oil circuit: Compressor → Oil separator → Oil return capillary → Suction pipe → Compressor.

[0093] The heating throttle valve in the refrigeration control system is fully open. The refrigeration throttle valves in the secondary pipelines are automatically controlled according to requirements.

[0094] As Figure 13 shown, the temperature changes evenly at the inlet and outlet of the battery cold plate. This will not cause damage to the battery body due to large temperature changes in the battery that is not in direct contact with the cold plate, thus affecting the service life of the battery. During the refrigeration process, the throttled refrigerant is distributed through the refrigeration distributor to achieve uniform distribution of the refrigerant flow rate entering each branch of the cold plate.

[0095] As Figure 14 shown, at the same time, the pressure drop at the inlet and outlet of each cold plate is controlled so that the pressure drop forms a refrigerant temperature change < 0.5°C, thereby controlling the saturated evaporation temperature range of the refrigerant inside the cold plate < 0.5°C, ensuring that the maximum temperature difference of each part of the cold plate < 0.5°C. This makes the temperature difference at each point on the contact surface of the battery cells smaller, which is beneficial to the control of the temperature consistency of the battery cells. When measuring the inlet and outlet temperatures of the traditional liquid-cooled cold plate, the temperature difference can reach 2.5°C. Such a large temperature difference is likely to cause chemical changes inside the battery cells, affecting the service life of the battery.

[0096] In the refrigeration control system, the inside of the cold plate is in a two-phase zone evaporation state, and the outlet is still in a liquid-carrying state. The temperature inside the cold plate is uniform. After the liquid-carrying gas at the outlet passes through the regenerator, it is in a saturated superheated state, which protects the stable operation of the compressor. At the same time, it exchanges heat with the high-temperature condensed liquid in front of the valve to reduce the liquid temperature.

[0097] As Figure 12 shown, the energy storage direct cooling system also includes a defrosting system, and the specific operation is as follows:

[0098] The oil separator 2 separates oil and gas. The refrigerant enters the outdoor heat exchanger 3, then enters the liquid storage tank 4 through the heating throttle 31, and then returns to the gas-liquid separator 9 through the hot gas defrosting valve 10, and then undergoes a secondary cycle defrosting through the compressor 1.

[0099] In the refrigeration control system and the defrosting system, the oil return path is separated by the oil separator 2 after being released by the compressor 1, recovered through the oil return capillary 21, and then returned to the compressor 1 through the suction pipe as a cyclic action.

[0100] At the same time, this application can also achieve efficiency improvement (reduce intermediate heat exchange).

[0101] Improvement of heat exchange efficiency in the refrigeration mode: The traditional method is: the liquid cooling heat exchange process is: battery cell → cold plate (water-cooled heat exchanger) → secondary coolant → plate heat exchanger (evaporator) → refrigerant.

[0102] As Figure 15 shown, the method adopted by the present utility model is: direct cooling heat exchange process: battery cell → cold plate (evaporator) → refrigerant.

[0103] In summary, the beneficial effects of the present utility model are:

[0104] 1. The multi-group outdoor heat exchangers adopted by this device for heat exchange operations have a heat efficiency 30% higher than that of a single refrigeration machine, and at the same time achieve energy-saving efficiency.

[0105] 2. This device uses a distributor to distribute the refrigerant more evenly, making the temperature difference between each circuit close, achieving energy saving while ensuring the stable operation of the device system.

[0106] 3. This device uses most of the pipe fittings to connect for refrigeration, so the connection points between components are significantly reduced, and the possibility of refrigerant overflow in the refrigeration process is also reduced, improving the stability of the overall device system operation.

[0107] 4. During the refrigeration process of this device, the inside of the cold plate uses two-phase zone heat transfer. The pressure in each branch is the same, the temperature of the cold plate is the same, and the temperature difference between the inlet and outlet of the cold plate is small, which can limit the deviation of the saturated evaporation temperature in the cold plate to within 0.5°C, so that the temperature difference at each point on the contact surface of the battery cell is smaller, which is beneficial to the control of the temperature consistency of the battery cell.

[0108] 5. The first-stage refrigerant used in this device is distributed to the second-stage refrigerant circuit and regulated by an electronic expansion valve, which can achieve multi-loop control and the average distribution of refrigerant between loops, so as to achieve the temperature management of multiple clusters of battery packs.

[0109] In summary, the thermal management systems of all the above embodiments can control and manage the temperature of the high-energy density energy storage box, and can effectively and reliably control the temperature uniformity of the energy storage system. The thermal management system passes the refrigerant into the heat transfer component 200 and directly exchanges heat with the energy storage component 100, with higher heat transfer efficiency. The thermal management system includes a cooling circulation path and a defrosting circulation path, with rich functions. By opening and closing the control valve to control the opening and closing of the pipeline, it can drive the conversion between the cooling circulation path and the defrosting circulation path, without the need to additionally set up a defrosting mechanism, which simplifies the setting cost of the system. At the same time, the setting of the fluid channel 230 of the heat transfer component 200 can control the magnitude of the pressure difference between the first port 210 and the second port 220, so as to control the pressure drop between the first port 210 and the second port 220. When the refrigerant is in a gas-liquid two-phase equilibrium state respectively, the temperature in the fluid channel 230 is uniform and the heat transfer effect is better.

[0110] The above embodiments are only used to illustrate the technical concept and features of the present invention. The purpose is to enable those who are familiar with this technology to understand the content of the present invention and implement it, and it cannot be used to limit the protection scope of the present invention. Any equivalent changes or modifications made according to the spirit and essence of the present invention should be covered within the protection scope of the present invention.

Claims

1. A direct cooling device of an energy storage system, the energy storage system comprising an energy storage component and a heat transfer component, the heat transfer component having a first port, a second port and a fluid channel connecting the first port and the second port, the first port and the second port being connectable to the direct cooling device through a first pipe and a second pipe, the direct cooling device comprising a heat supply module, a valve assembly, and a detection control module, characterized in that: The heat supply module includes a gas compressor, a gas-liquid separator, a first heat exchanger, a regenerator, and a fluid storage tank. The regenerator has a first fluid passage and a second fluid passage that are independent of each other but can exchange heat with each other. The outlet of the gas compressor, the first heat exchanger, the fluid storage tank, the first fluid passage of the regenerator, and the first pipeline are connected in sequence through pipelines to form a cooling passage for supplying a refrigerant with a preset temperature to the heat transfer component, wherein a first electronic expansion valve is provided on the pipeline between the first fluid passage of the regenerator and the first pipeline; the second pipeline, the second fluid passage of the regenerator, the gas-liquid separator, and the inlet of the gas compressor are connected in sequence through pipelines to form a cooling reflux passage for recovering the refrigerant, and the cooling passage, the fluid channel in the heat transfer component, and the cooling reflux passage constitute a cooling circulation passage; The direct cooling device may also optionally include a refrigerant in a gas-liquid two-phase equilibrium state at the preset temperature; The detection control module includes a controller and a pressure sensor disposed in a pipeline included in the heat supply module and electrically or signal-connected to the controller. The heat supply module is connected to the controller and is controlled by the controller.

2. The direct cooling device of the energy storage system according to claim 1, characterized in that: The pressure sensor includes a first pressure sensor arranged at the inlet of the gas compressor and a second pressure sensor arranged at the outlet of the gas compressor; and / or, the controller is electrically or communicatively connected to the gas compressor, and the controller is configured to adjust the rotation speed of the gas compressor according to the detection value of the pressure sensor; and / or, the controller is electrically or communicatively connected to the valve assembly, and the controller is configured to control the opening and closing and / or opening degree of the valve according to a preset program.

3. The direct cooling device of the energy storage system according to claim 1, characterized in that: The preset temperature is above 15 degrees Celsius and below 25 degrees Celsius; and / or the refrigerant is R134a, R1234yf, R410A, R513A, R513B or R454B.

4. The direct cooling device of the energy storage system according to claim 1, characterized in that: The fluid channel includes a plurality of first channels arranged in parallel along a first direction, and a second channel connected between the first channels, so that a pressure difference when the fluid flows from the first port through the fluid channel to the second port is less than a preset value; And / or, a projection of the energy storage component on the heat transfer component falls within the distribution range of the fluid channel.

5. The direct cooling device of the energy storage system according to claim 4, characterized in that: Along a second direction perpendicular to the first direction, the first port and the second port are respectively arranged on different sides of the heat transfer component, and along the second direction, the fluid channel extends from the first port to the second port along an S-shaped extension trajectory; Alternatively, along a second direction perpendicular to the first direction, the first port and the second port are arranged on the same side of the heat transfer component, the fluid channel extends along the second direction from the first port along an S-shaped extension trajectory to the other side of the heat transfer component, and extends in the second direction from the side away from the first port along the S-shaped extension trajectory in the opposite direction to the second port; Alternatively, along a second direction perpendicular to the first direction, the outermost first channel is connected to the first port, and any other first channel is connected to the second port, and two second channels are provided, and along the first direction, they are located on the side away from the first port, one of the second channels connects the ends of all the first channels together and is located on the side close to the first port, and the other second channel connects the ends of all the first channels except the first channel connected to the first port together; Alternatively, along a second direction perpendicular to the first direction, the first channel is connected to the second channel to form a plurality of rectangular loops distributed at intervals, the fluid channel further comprises a third channel connecting the plurality of rectangular loops in series, a free end of the third channel is connected to the first port, and the other free end of the third channel is connected to the second port; Alternatively, along a second direction perpendicular to the first direction, the first channel is connected to the second channel to form a plurality of rectangular loops distributed at intervals, the fluid channel includes a fourth channel connected between the two outermost rectangular loops in the second direction, the first port is arranged on the fourth channel, two adjacent rectangular loops are connected by a fifth channel, and along the second direction, the fifth channels are alternately distributed on different sides of the rectangular loops along the first direction, and the second port is arranged on the fifth channel; Alternatively, the fluid channel is spiral.

6. The direct cooling device of the energy storage system according to claim 1, characterized in that: The outlet of the gas compressor, the first heat exchanger, the fluid storage tank, the first fluid passage of the regenerator, the first electronic expansion valve, the gas-liquid separator, and the inlet of the gas compressor are connected in sequence through pipelines to form a defrost circulation passage.

7. The direct cooling device of the energy storage system according to claim 6, characterized in that: The valve assembly includes a first solenoid valve arranged on the pipeline between the gas compressor and the first heat exchanger, a second solenoid valve arranged on the pipeline between the second pipeline and the second fluid passage of the regenerator, a third solenoid valve arranged on the pipeline between the first electronic expansion valve and the gas-liquid separator, and a stop valve arranged on the first pipeline and the second pipeline. The controller is electrically connected to the valve assembly, and the controller is configured to control the opening or closing of the solenoid valve; the first solenoid valve and the second solenoid valve are opened, the third solenoid valve is closed, and the cooling circulation passage is opened; the first solenoid valve and the third solenoid valve are opened, the second solenoid valve is closed, and the defrost circulation passage is opened.

8. The direct cooling device of the energy storage system according to claim 1, characterized in that: The direct cooling device includes a temperature sensor, wherein the temperature sensor includes a first temperature sensor arranged on a pipeline between the first fluid passage of the regenerator and the first electronic expansion valve, a second temperature sensor arranged on a pipeline between the first fluid passage of the regenerator and the fluid storage tank, a third temperature sensor arranged on a pipeline between the second fluid passage of the regenerator and the second pipeline, and a fourth temperature sensor arranged at the inlet of the gas compressor. The controller is electrically connected or communicatively connected to the temperature sensor, and the controller is electrically connected to the first electronic expansion valve. The controller is configured to acquire data from the temperature sensor and adjust the opening of the first electronic expansion valve according to the acquired data.

9. A thermal management system for an energy storage system, characterized in that: It comprises a direct cooling device of an energy storage system as claimed in any one of claims 1 to 8 and a plurality of groups of heat transfer components, each of the heat transfer components being the same as the heat transfer component described in any one of claims 1 to 8.

10. The thermal management system of the energy storage system according to claim 9, characterized in that: The multiple groups of heat transfer components are arranged in parallel, and a liquid distributor is provided on the first pipe and the second pipe, and the liquid distributor is used to evenly distribute the refrigerant to the multiple groups of heat transfer components; Alternatively, a plurality of parallel branches arranged in parallel are formed between the first pipeline and the second pipeline, each parallel branch is provided with a group of the heat transfer components, and each parallel branch is provided with a liquid separation valve for controlling the refrigerant flow rate.

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