Submerged liquid-cooled energy storage battery system

Abstract

The application discloses an immersed liquid cooling energy storage battery system, which comprises a containing frame, a plurality of battery packs and a refrigerating device, the battery packs are installed on the containing frame, each battery pack comprises a box body, a plurality of battery modules and a gas permeable device, the box body is provided with a liquid inlet interface and a liquid return interface, the plurality of battery modules are arranged in the box body at intervals, and the gas permeable device is used for balancing the air pressure inside and outside the battery pack; the refrigerating device is provided with a plurality of first connecting pipes and second connecting pipes which are communicated with the liquid inlet interface and the liquid return interface, the refrigerating device delivers cooling liquid to each battery pack through the first connecting pipe and recovers the cooling liquid from each battery pack through the second connecting pipe, and the refrigerating device is used for controlling the temperature of the cooling liquid respectively. The immersed liquid cooling energy storage battery system can provide a single liquid cooling circulation loop for the plurality of battery packs, is favorable for the battery cells of the battery pack to meet the uniform temperature requirement and solves the problem of excessive air pressure of the battery pack, and further effectively inhibits the occurrence of the thermal runaway of the battery cells.

Description

Technical Field

[0001] This invention relates to the field of submerged liquid-cooled energy storage battery technology, and more particularly to a submerged liquid-cooled energy storage battery system. Background Technology

[0002] With the widespread application of energy storage battery systems, and the need for current energy storage battery systems to continuously improve energy density and power density to meet actual usage requirements, their safety is receiving increasing attention.

[0003] Increased power density in energy storage battery systems leads to greater heat generation and power consumption of the cells. If the cell temperature is not controlled in a timely and effective manner, it may cause thermal runaway of the cells, resulting in fire or even explosion of the energy storage battery system.

[0004] However, most existing energy storage battery systems use air cooling or cold plate liquid cooling for battery temperature control. Some energy storage battery systems use immersion liquid cooling, which involves placing multiple battery modules in the same enclosure and filling the enclosure with coolant, to achieve battery temperature control. However, neither of these temperature control methods can ensure that the battery cells of the battery modules meet the requirements for temperature uniformity or solve the problem of thermal runaway of the cells. Summary of the Invention

[0005] The purpose of this invention is to provide an immersion liquid-cooled energy storage battery system that can provide separate liquid-cooled circulation loops for multiple battery packs. This helps the battery cells in the battery pack achieve the required temperature uniformity and solves the problem of excessive pressure in the battery pack, thereby effectively suppressing the occurrence of thermal runaway of the cells and ensuring the safety of the energy storage battery system.

[0006] To achieve the above objectives, this invention discloses an immersion liquid-cooled energy storage battery system, comprising: a housing frame, multiple battery packs, and a cooling device. The housing frame is provided with multiple housing positions; the multiple battery packs are respectively installed in corresponding housing positions. Each battery pack includes a housing, multiple battery modules, and a venting device. The housing is provided with a liquid inlet and a liquid return port penetrating its wall. The multiple battery modules are arranged at intervals within the housing. The venting device is disposed on the wall of the housing and is used to balance the air pressure inside and outside the battery pack. The cooling device is provided with multiple first connecting pipes and multiple second connecting pipes. Each first connecting pipe and each second connecting pipe is respectively connected to the liquid inlet and the liquid return port of a battery pack. The cooling device delivers coolant to each battery pack through the first connecting pipes and recovers coolant from each battery pack through the second connecting pipes. The cooling device is used to control the temperature of the coolant flowing to each battery pack.

[0007] Optionally, the battery pack is provided with an inlet conduit communicating with the liquid inlet interface and a return conduit communicating with the liquid return interface. The inlet conduit and the return conduit are respectively located on the two inner sides of the housing along the lateral direction. The side of the inlet conduit and the return conduit close to the battery module is provided with a plurality of through holes spaced apart along the longitudinal direction.

[0008] Optionally, multiple battery modules extend longitudinally and are arranged side-by-side laterally. Multiple first flow channels are formed between two adjacent battery modules. Multiple second flow channels are formed between the inner sidewall of the housing and the battery modules. A third flow channel is formed between the top wall of the housing and the battery modules. The two sides of the first flow channels are respectively connected to two second flow channels arranged longitudinally, so that coolant flows through the first and second flow channels over the four outer sidewalls of each battery module. The third flow channel is connected to the first and second flow channels, so that coolant flows through the third flow channel over the upper surface of each battery module.

[0009] Optionally, the housing is provided with a pressure relief port penetrating its wall, and the venting device includes a venting valve, which is disposed at the pressure relief port and is used to control the unidirectional discharge of gas from the housing.

[0010] Optionally, each of the battery modules includes multiple cells arranged longitudinally and multiple connectors. The multiple cells of the multiple battery modules are connected in series through the multiple connectors. The casing wall is provided with a positive connector and a negative connector. The positive connector and the negative connector are electrically connected to the two ends of the series-connected battery modules, respectively.

[0011] Optionally, the refrigeration device includes multiple coolant circulation modules and multiple coolant cooling devices. Each coolant circulation module includes a heater and an electric water pump. The two ends of the heater are respectively connected to the first connecting pipe and the first output end of the corresponding coolant cooling device. The heater is used to heat the coolant output by the coolant cooling device to a set temperature and output it through the first connecting pipe. The two ends of the electric water pump are respectively connected to the second connecting pipe and the first input end of the corresponding coolant cooling device. The electric water pump is used to draw the coolant returning from the battery pack through the second connecting pipe.

[0012] Optionally, each of the battery packs is provided with a first temperature sensor for detecting the temperature of the battery module. The cooling device is provided with multiple second temperature sensors corresponding to the multiple second connecting pipes. The second temperature sensors are used to detect the temperature of the coolant flowing back through the second connecting pipes. The cooling device is used to adjust the temperature of the coolant flowing to the corresponding first connecting pipe according to the detection information of the first temperature sensor or the second temperature sensor.

[0013] Optionally, the refrigeration device includes multiple heat exchange modules and a refrigerant circulation module. Each heat exchange module includes a heat exchanger and an expansion valve. The heat exchanger is connected to the corresponding first connecting pipe and second connecting pipe. The refrigerant circulation module includes a compressor and a condenser. The input end of the compressor is connected to the second output end of each heat exchanger. The two ends of the condenser are respectively connected to the output end of the compressor and the input end of each expansion valve. The output end of each expansion valve is respectively connected to the second input end of the corresponding heat exchanger. The compressor is used to compress the refrigerant output from each heat exchanger into a high-temperature, high-pressure gaseous refrigerant. The condenser is used to condense the gaseous refrigerant into a liquid refrigerant. Each expansion valve is used to throttle the incoming liquid refrigerant into a low-temperature, low-pressure two-phase refrigerant. Each heat exchanger is used to allow the two-phase refrigerant to exchange heat with the coolant to absorb heat from the coolant.

[0014] This invention provides separate liquid-cooled circulation loops for multiple battery packs, each installed in a housing position on a housing frame. Multiple battery modules are spaced apart within the battery pack housing. The housing walls are equipped with through-hole liquid inlet and return ports, as well as a venting device to balance the internal and external air pressure of the battery pack, effectively solving the problem of excessive battery pack pressure and ensuring the safety of the energy storage battery system. The liquid inlet and return ports of each battery pack are connected to a cooling device via a first connecting pipe and a second connecting pipe, respectively. The cooling device supplies coolant to each battery pack through the first connecting pipe and recovers coolant from each battery pack through the second connecting pipe, controlling the temperature of the coolant flowing to each battery pack. This helps the battery cells achieve temperature uniformity and effectively suppresses thermal runaway of the cells. Attached Figure Description

[0015] Figure 1 This is a front view of an immersion liquid-cooled energy storage battery system according to an embodiment of the present invention.

[0016] Figure 2 This is a three-dimensional structural diagram of the battery pack in the submerged liquid-cooled energy storage battery system according to an embodiment of the present invention.

[0017] Figure 3This is a three-dimensional structural view of the battery pack in the submerged liquid-cooled energy storage battery system according to an embodiment of the present invention.

[0018] Figure 4 This is a schematic diagram of the structure of an immersed liquid-cooled energy storage battery system according to an embodiment of the present invention. Detailed Implementation

[0019] To illustrate the technical content, structural features, objectives, and effects of the present invention in detail, the following description is provided in conjunction with the embodiments and accompanying drawings.

[0020] Please see Figures 1 to 4 This invention discloses an immersion liquid-cooled energy storage battery system, comprising: a housing frame 1, multiple battery packs 2, and a cooling device 3. The housing frame 1 is provided with multiple housing positions 11; the multiple battery packs 2 are respectively installed in the corresponding housing positions 11. Each battery pack 2 includes a housing 21, multiple battery modules 22, and a venting device 23. The housing 21 is provided with a liquid inlet port 211 and a liquid return port 212 penetrating its wall. The multiple battery modules 22 are arranged at intervals inside the housing 21, and the venting device 23 is provided in the housing 21. The cooling device 3 is equipped with multiple first connecting pipes 31 and multiple second connecting pipes 32. Each first connecting pipe 31 and each second connecting pipe 32 is connected to the liquid inlet 211 and the liquid return 212 of a battery pack 2, respectively. The cooling device 3 delivers coolant to each battery pack 2 through the first connecting pipe 31 and recovers coolant from each battery pack 2 through the second connecting pipe 32. The cooling device 3 is used to control the temperature of the coolant flowing to each battery pack 2.

[0021] This invention provides separate liquid cooling circulation loops for multiple battery packs 2. The multiple battery packs 2 are respectively installed on the receiving positions 11 of the receiving frame 1. Multiple battery modules 22 are arranged at intervals inside the housing 21 of the battery pack 2. The housing 21 is provided with a through liquid inlet port 211 and a liquid return port 212, as well as a venting device 23 to balance the air pressure inside and outside the battery pack 2, so as to effectively solve the problem of excessive pressure in the battery pack 2 and ensure the safety of the energy storage battery system. The liquid inlet port 211 and the liquid return port 212 of each battery pack 2 are respectively connected to the cooling device 3 through the first connecting pipe 31 and the second connecting pipe 32. The cooling device 3 delivers coolant to each battery pack 2 through the first connecting pipe 31 and recovers coolant from each battery pack 2 through the second connecting pipe 32, and controls the temperature of the coolant flowing to each battery pack 2, which is conducive to the battery cells of the battery pack 2 achieving the temperature uniformity requirements and effectively suppressing the occurrence of thermal runaway of the battery cells.

[0022] See Figures 1 to 4The battery pack 2 is provided with an inlet conduit 241 connected to the inlet interface 211 and a return conduit 242 connected to the return interface 212. The inlet conduit 241 and the return conduit 242 are respectively located on the two inner sides of the housing 21 along the lateral direction. The side of the inlet conduit 241 and the return conduit 242 near the battery module 22 is provided with multiple through holes 243 at intervals along the longitudinal direction, which is conducive to the coolant quickly entering the housing 21 and timely removing the heat generated by the battery module 22, so as to avoid thermal runaway of the battery as much as possible.

[0023] Optionally, multiple battery modules 22 extend longitudinally and are arranged side by side laterally. Multiple first flow channels 213 are formed between two adjacent battery modules 22. Multiple second flow channels 214 are formed between the inner sidewall of the housing 21 and the battery modules 22. A third flow channel 210 is formed between the top wall of the housing 21 and the battery modules 22. The two sides of the first flow channels 213 are respectively connected to the two longitudinally arranged second flow channels 214, so that the coolant flows through the first flow channels 213 and the second flow channels 214 over the four outer sidewalls of each battery module 22. The third flow channel 210 is connected to the first flow channels 213 and the second flow channels 214, so that the coolant flows through the third flow channel 210 over the upper surface of each battery module 22, so that the battery module 22 is completely immersed in the coolant, thereby cooling the battery module 22 in all directions and improving the heat dissipation effect, heat dissipation efficiency and reliability of the energy storage battery system.

[0024] Specifically, in this embodiment, coolant flows into the housing 21 from the through hole 243 of the inlet conduit 241, and quickly flows into the first flow channel 213, and then into the second flow channel 214 through the first flow channel 213, and into the third flow channel 210 through the first flow channel 213 and the second flow channel 214, so that the sides and top surface of each battery module 22 are filled with coolant, which is beneficial for the battery module 22 to have full contact with the coolant and achieve the effect of rapid heat exchange. Then the coolant flows out from the through hole 243 of the return conduit 242 in the first flow channel 213.

[0025] See Figures 1 to 4 The housing 21 is provided with a pressure relief port 215 penetrating its wall. The venting device 23 includes a venting valve 231, which is located at the pressure relief port 215. The venting valve 231 is used to control the gas inside the housing 21 to be discharged from the housing 21 in one direction, so as to effectively balance the pressure difference between the inside and outside of the housing 21.

[0026] Specifically, in this embodiment, the pressure relief port 215 is located at a height higher than the coolant level in the housing 21. When the cell 221 experiences thermal runaway due to a short circuit or other reasons, it will generate a large amount of gas. The vent valve 231 can promptly discharge the gas generated by the cell 221 through the pressure relief port 215, which, together with the coolant, quickly cools down the thermally runaway cell 221, effectively ensuring that no explosion or fire will occur inside the battery pack 2, and improving the overall safety performance of the energy storage battery system.

[0027] See Figures 1 to 4 Each battery module 22 includes multiple cells 221 arranged longitudinally and multiple connectors 222. The multiple cells 221 of the multiple battery modules 22 are connected in series through multiple connectors 222. The casing wall of the housing 21 is provided with a positive connector 216 and a negative connector 217. The positive connector 216 and the negative connector 217 are electrically connected to the two ends of the series-connected battery modules 22, respectively.

[0028] Specifically, in this embodiment, the housing 21 includes a frame portion 218 with a placement slot 2181 and a detachable cover portion 219 sealed and assembled on the top of the frame portion 218. Multiple battery modules 22 are arranged laterally at intervals in the placement slot 2181 of the frame portion 218. The two ends of the connector 222 are electrically connected to the positive electrode of one of the two adjacent battery cells 221 and the negative electrode of the other battery cell 221, respectively. The front side wall of the frame portion 218 is provided with an inlet port 211, a return port 212, a pressure relief port 215, a positive connector 216, and a negative connector 217. The inlet port 211 and the return port 212 are respectively provided with bent pipes 201 that communicate with the inlet conduit 241 and the return conduit 242. The positive connector 216 and the negative connector 217 are respectively provided with bent electrical connectors 202 that are electrically connected to the connectors 222 at both ends of the series-connected battery modules 22, but are not limited thereto.

[0029] See Figures 1 to 4 The cooling device 3 includes multiple coolant circulation modules 31 and coolant cooling devices 32. Each coolant circulation module 31 includes a heater 311 and an electric water pump 312. The two ends of the heater 311 are connected to the first connecting pipe 31 and the first output end of the coolant cooling device 32, respectively. The heater 311 is used to heat the coolant output from the coolant cooling device 32 to a set temperature and output it through the first connecting pipe 31. The two ends of the electric water pump 312 are connected to the second connecting pipe 32 and the first input end of the coolant cooling device 32, respectively. The electric water pump 312 is used to draw the coolant returning from the battery pack 2 through the second connecting pipe 32. In the entire energy storage battery system, the cooling device 3 is equipped with an independent coolant circulation system for each battery pack 2. With the liquid cooling circuit set for each battery pack 2, the coolant between each battery pack 2 does not affect each other, effectively solving the problem of excessive pressure in the battery pack 2.

[0030] Specifically, in this embodiment, the housing frame 1 is provided with multiple housing positions 11 along the vertical direction, and a cooling device 3 is installed on one side of the housing position 11. The cooling device 3 is connected to multiple first connecting pipes 31 and multiple second connecting pipes 32 along the vertical direction. Each coolant circulation module 31 is connected to the inlet port 211 and return port 212 of a corresponding battery pack 2 through the first connecting pipe 31 and the second connecting pipe 32. Then, the high-temperature coolant is drawn back by the electronic water pump 312, and the coolant is cooled by the coolant cooling device 32 before being transported back to the battery pack 2 to form multiple independent coolant circulation loops, but not limited to this.

[0031] Optionally, each battery pack 2 is provided with a first temperature sensor 223, which is used to detect the temperature of the battery module 22. The cooling device 3 is provided with a plurality of second temperature sensors 313 corresponding to a plurality of second connecting pipes 32. The second temperature sensors 313 are used to detect the temperature of the coolant flowing back through the second connecting pipes 32. The cooling device 3 is used to adjust the temperature of the coolant flowing to the corresponding first connecting pipe 31 according to the detection information of the first temperature sensor 223 or the second temperature sensor 313.

[0032] Specifically, in this embodiment, the cooling device 3 is equipped with a controller 33, which is communicatively connected to the heaters 311 of each coolant circulation module 31, and communicatively connected to each first temperature sensor 223 and each second temperature sensor 313 to obtain their temperature detection information. Based on this information, the controller adjusts the set temperature of the heaters 311 in the corresponding coolant circulation module 31 so that the heaters 311 heat the coolant at a lower temperature to a suitable temperature. The coolant at a suitable temperature enters the corresponding battery pack 2 to exchange heat with the battery module, which is beneficial to keep the cells 221 of the battery module 22 at the optimal temperature for charging and discharging, but is not limited to this.

[0033] Optionally, the refrigeration device 3 includes multiple heat exchange modules 34 and multiple refrigerant circulation modules 35. Each heat exchange module 34 includes a heat exchanger 341 and an expansion valve 342. The heat exchanger 341 is connected to a corresponding first connecting pipe 31 and a second connecting pipe 32. The refrigerant circulation module 35 includes a compressor 351 and a condenser 352. The input end of the compressor 351 is connected to the second output end of each heat exchanger 341, and the two ends of the condenser 352 are respectively connected to the output end of the compressor 351 and each expansion valve 341. The input terminal of 2 is connected, and the output terminal of each expansion valve 342 is connected to the second input terminal of the corresponding heat exchanger 341. The compressor 351 is used to compress the refrigerant output from each heat exchanger 341 into a high-temperature and high-pressure gaseous refrigerant. The condenser 352 is used to condense the gaseous refrigerant into a liquid refrigerant. Each expansion valve 342 is used to throttle the incoming liquid refrigerant into a low-temperature and low-pressure two-phase refrigerant. Each heat exchanger 341 is used to allow the two-phase refrigerant to exchange heat with the coolant in order to absorb the heat of the coolant.

[0034] Specifically, in this embodiment, after the refrigerant passes through the compressor 351, condenser 352 and expansion valve 342 in the refrigeration process, it enters the heat exchanger 341 of the corresponding heat exchange module 34 and exchanges heat with the coolant to absorb the heat of the coolant. Then, the refrigerant in each heat exchanger 341 is drawn back into the compressor 351, thus completing one refrigeration cycle and starting a new refrigeration cycle, but not limited to this.

[0035] The above-disclosed embodiments are merely preferred embodiments of the present invention and should not be construed as limiting the scope of the present invention. Therefore, any equivalent variations made in accordance with the claims of the present invention are still within the scope of the present invention.

Claims

1. An immersion liquid-cooled energy storage battery system, characterized in that, include: A receiving frame, wherein the receiving frame is provided with multiple receiving positions; Multiple battery packs are installed in corresponding receiving positions. Each battery pack includes a housing, multiple battery modules, and a venting device. The housing is provided with a liquid inlet and a liquid return port that penetrate its housing wall. The multiple battery modules are arranged at intervals in the housing. The venting device is provided on the housing wall and is used to balance the air pressure inside and outside the battery pack. The refrigeration device includes multiple first connecting pipes and multiple second connecting pipes. Each first connecting pipe and each second connecting pipe is respectively connected to the liquid inlet and liquid return interface of a battery pack. The refrigeration device supplies coolant to each battery pack through the first connecting pipes and recovers coolant from each battery pack through the second connecting pipes. The refrigeration device is used to control the temperature of the coolant flowing to each battery pack. The battery pack is provided with an inlet conduit communicating with the liquid inlet interface and a return conduit communicating with the liquid return interface. The inlet conduit and the return conduit are respectively located on the two inner sides of the housing along the lateral direction. The side of the inlet conduit and the return conduit near the battery module is provided with multiple through holes spaced apart along the longitudinal direction. Multiple battery modules extend longitudinally and are arranged side-by-side laterally. Multiple first flow channels are formed between two adjacent battery modules. Multiple second flow channels are formed between the inner sidewall of the housing and the battery modules. A third flow channel is formed between the top wall of the housing and the battery modules. The two sides of the first flow channels are respectively connected to two second flow channels arranged longitudinally, so that coolant flows through the first and second flow channels over the four outer sidewalls of each battery module. The third flow channel is connected to the first and second flow channels, so that coolant flows through the third flow channel over the upper surface of each battery module.

2. The immersion liquid-cooled energy storage battery system according to claim 1, characterized in that, The enclosure is provided with a pressure relief port that penetrates its wall. The venting device includes a venting valve, which is located at the pressure relief port and is used to control the unidirectional discharge of gas from the enclosure.

3. The immersion liquid-cooled energy storage battery system according to claim 1, characterized in that, Each battery module includes multiple cells arranged longitudinally and multiple connectors. The multiple cells of multiple battery modules are connected in series through the multiple connectors. The casing wall is provided with a positive connector and a negative connector. The positive connector and the negative connector are electrically connected to the two ends of the series-connected battery modules, respectively.

4. The immersion liquid-cooled energy storage battery system according to claim 1, characterized in that, The refrigeration device includes multiple coolant circulation modules and multiple coolant cooling devices. Each coolant circulation module includes a heater and an electric water pump. The two ends of the heater are respectively connected to the first connecting pipe and the first output end of the corresponding coolant cooling device. The heater is used to heat the coolant output by the coolant cooling device to a set temperature and output it through the first connecting pipe. The two ends of the electric water pump are respectively connected to the second connecting pipe and the first input end of the corresponding coolant cooling device. The electric water pump is used to draw the coolant returning from the battery pack through the second connecting pipe.

5. The immersion liquid-cooled energy storage battery system according to claim 1, characterized in that, Each of the battery packs is provided with a first temperature sensor, which is used to detect the temperature of the battery module. The cooling device is provided with a plurality of second temperature sensors corresponding to the plurality of second connecting pipes. The second temperature sensors are used to detect the temperature of the coolant flowing back through the second connecting pipes. The cooling device is used to adjust the temperature of the coolant flowing to the corresponding first connecting pipe according to the detection information of the first temperature sensor or the second temperature sensor.

6. The immersion liquid-cooled energy storage battery system according to claim 1, characterized in that, The refrigeration device includes multiple heat exchange modules and a refrigerant circulation module. Each heat exchange module includes a heat exchanger and an expansion valve. The heat exchanger is connected to the corresponding first connecting pipe and second connecting pipe. The refrigerant circulation module includes a compressor and a condenser. The input end of the compressor is connected to the second output end of each heat exchanger. The two ends of the condenser are respectively connected to the output end of the compressor and the input end of each expansion valve. The output end of each expansion valve is respectively connected to the second input end of the corresponding heat exchanger. The compressor is used to compress the refrigerant output from each heat exchanger into a high-temperature, high-pressure gaseous refrigerant. The condenser is used to condense the gaseous refrigerant into a liquid refrigerant. Each expansion valve is used to throttle the incoming liquid refrigerant into a low-temperature, low-pressure two-phase refrigerant. Each heat exchanger is used to allow the two-phase refrigerant to exchange heat with the coolant to absorb heat from the coolant.

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