Immersed direct-cooling battery pack

Abstract

The invention discloses an immersed direct-cooling battery pack, and relates to the technical field of electrochemical energy storage, the immersed direct-cooling battery pack comprises a box body, a plurality of battery modules are accommodated in an inner cavity of the box body, a tray is fixed in the box body, a plurality of cooling pipes are uniformly distributed on the end surface of one side, deviating from the battery modules, of the tray, and a refrigerant circularly flows in the cooling pipes; a plurality of pressure relief valve holes are uniformly distributed in the tray, the chambers on the two sides of the tray are communicated through the pressure relief valve holes, an inner cavity of the box body is filled with heat conduction liquid, the cooling pipes are immersed in the heat conduction liquid, an upper cover is arranged at a port of the box body, and the inner cavity of the box body is sealed by the upper cover. The technical problems that a traditional air cooling mode and an indirect liquid cooling mode are low in heat dissipation efficiency and uneven in temperature, and heat generated by the battery cannot be dissipated in time under the high-load working condition, so that the thermal runaway risk is caused, and the reliability of a battery system is seriously affected are solved.

Description

Technical Field

[0001] This invention relates to the field of electrochemical energy storage technology, and in particular to an immersion-type direct-cooled battery pack. Background Technology

[0002] With the rapid development of electrochemical energy storage technology, thermal management has become a core technical challenge affecting the performance, safety, and lifespan of energy storage battery packs. Traditional air cooling and indirect liquid cooling methods have inherent defects such as low heat dissipation efficiency and uneven temperature distribution. Under high-load operating conditions, the heat generated by the cells is difficult to dissipate quickly, which can easily lead to thermal runaway risks and seriously reduce the reliability of system operation. Currently, most mainstream submerged battery packs adopt a bottom cooling combined with passive or active immersion. The cold plate is located below the cells, but the heat at the top of the cells needs to be transferred from top to bottom through the immersion liquid. The heat conduction path is long, which can easily lead to thermal stratification and large temperature differences between the top and bottom of the cells, affecting battery consistency. Active immersion also requires the configuration of pump sets and pipelines, increasing system costs and the requirements for enclosure sealing and strength. At the same time, the existing surrounding coil heat exchange solution does not match the heat exchange path of the upper part of the cells, resulting in a delayed response to the top hot spots. It also has problems such as complex structure, low space utilization, and high risk of cooling medium leakage.

[0003] In summary, developing a battery pack with a simple structure, adapted to the heating characteristics of batteries, and with stable heat dissipation is a problem that urgently needs to be solved by those skilled in the art. Summary of the Invention

[0004] The purpose of this invention is to provide an immersion-type direct-cooled battery pack, which solves the problems of low heat dissipation efficiency and uneven temperature in traditional air cooling and indirect liquid cooling methods. Furthermore, under high-load operating conditions, the heat generated by the battery cannot be dissipated in time, leading to the risk of thermal runaway and seriously affecting the reliability of the battery system.

[0005] To achieve the above objectives, the present invention provides an immersion-type direct-cooled battery pack, comprising:

[0006] The enclosure contains several battery modules. A tray is fixed inside the enclosure. Several cooling pipes are evenly distributed on the side of the tray away from the battery modules. Cooling medium circulates in the cooling pipes. Several flow holes are evenly distributed on the tray, and each flow hole connects the chambers on both sides of the tray. The inner cavity of the enclosure is filled with heat-conducting liquid, which immerses each cooling pipe. A top cover is provided at the port of the enclosure, which seals the inner cavity of the enclosure.

[0007] Preferably, each battery module is fixed with a temperature sensor at one end near the tray, and each temperature sensor is signal-connected to a temperature management component. The temperature management component is signal-connected to a communication component. When the temperature sensor detects that the temperature of the battery module exceeds the preset value, the communication component sends an operating signal to the direct cooling unit, which is used to deliver refrigerant to each cooling pipe.

[0008] Preferably, each cooling pipe is S-shaped and connected in series. A pipe groove is provided on the end face of the tray away from the battery module. Each cooling pipe is fitted into the pipe groove. Several pairs of cable tie holes are symmetrically provided on both sides of the pipe groove. Cable ties are inserted into the cable tie holes to fix the cooling pipe.

[0009] Preferably, the tray has a plurality of fixing grooves evenly distributed on the end face facing the top cover, each fixing groove being used to fix the cushioning pad, and the cushioning pad abutting against the top cover.

[0010] Preferably, the enclosure includes a frame and a base plate. An installation beam is fixedly connected to the inner cavity of the frame. The installation beam is used to fix each battery module. The temperature management component is fixed to the inner wall of the frame. The two ends of the series-connected cooling pipes are connected to the input and output ports of the direct cooling unit through compression fittings.

[0011] Preferably, the base plate is used to support each battery module, and several grooves are evenly distributed on the side end face of the base plate near the battery module, and each groove is arranged parallel to the mounting beam.

[0012] Preferably, an oil level indicator is provided on the side wall of the enclosure, which is used to detect the liquid level of the heat transfer fluid inside the box.

[0013] Preferably, a ball valve is provided on the side edge of the frame wall near the bottom plate. The ball valve is used for liquid injection or drainage of the tank. The ball valve, communication components, various compression fittings and oil level indicator are all located on the same side wall of the frame.

[0014] Preferably, the top cover has an exhaust port and a pressure relief valve on the side facing away from the battery module, and both the pressure relief valve and the exhaust port are connected to the inner cavity of the box.

[0015] Preferably, the port edge of the housing has a connecting plate extending outward, and each connecting plate has a number of fixing holes evenly distributed. Each connecting plate is used to support the top cover, and each fixing hole is fitted with a fastening screw, which fixes the top cover to the housing. A sealing strip is sandwiched between the top cover and the connecting plate.

[0016] Compared with the above-mentioned background technology, the immersion direct-cooling battery pack provided by the present invention includes: a box body, a plurality of battery modules are accommodated in the inner cavity of the box body, a tray is provided in the inner cavity of the box body, the tray is horizontally arranged and located above each battery module, the tray divides the inner cavity of the box body into two parts, a plurality of cooling pipes are evenly distributed on the end face of the tray away from each battery module, a plurality of flow holes are also evenly distributed on the end face of the tray, each flow hole connects the chambers on both sides of the tray, a certain volume of heat-conducting liquid is injected into the inner cavity of the box body, so that the liquid level of the heat-conducting liquid is higher than each cooling pipe, and a top cover is fixed at the port of the box body, the top cover seals the inner cavity of the box body. During the charging and discharging process of the battery module, the main heat-generating area is located on the side near the tray. Refrigerant circulates in each cooling pipe. The heat-conducting liquid in the heat-generating area absorbs the heat of the battery module. After heating up, the density of the heat-conducting liquid decreases, and the heat-conducting liquid floats upward and passes through the flow hole. The refrigerant in the cooling pipe circulates to the outside of the box after absorbing the heat of the heat-conducting liquid, thus completing the heat dissipation of the battery module. After cooling down, the density of the heat-conducting liquid increases, and the heat-conducting liquid flows to the side away from the top cover, causing the heat-conducting liquid at the lower end of the electromagnetic module to flow upward. The heat-conducting liquid forms convection in the box, achieving uniform heat dissipation of the battery module.

[0017] This application places the cooling pipe at the top of the battery module where the main heat is generated. The top direct cooling method causes the low-temperature heat transfer fluid after cooling at the top to sink and drive the high-temperature heat transfer fluid at the bottom to rise. Through convection, the heat transfer fluid circulates, which improves the heat exchange efficiency between the battery module and the cooling pipe, as well as the temperature uniformity of the battery module. Attached Figure Description

[0018] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on the provided drawings without creative effort.

[0019] Figure 1 This is an exploded view of an immersion-cooled battery pack provided in an embodiment of the present invention;

[0020] Figure 2 This is a structural diagram of the box provided in an embodiment of the present invention;

[0021] Figure 3 This is a structural diagram of the box and pallet assembly provided in an embodiment of the present invention;

[0022] Figure 4 This is a cross-sectional view of an immersion-cooled battery pack provided in an embodiment of the present invention;

[0023] Figure 5 This is a diagram of the tray structure provided in an embodiment of the present invention.

[0024] The components are as follows: 1-box body; 11-mounting beam; 12-groove; 13-compression fitting; 2-top cover; 21-exhaust port; 22-pressure relief valve; 3-tray; 31-pipe groove; 32-fixing groove; 33-buffer pad; 34-flow hole; 35-cable tie hole; 4-battery module; 5-cooling pipe; 6-temperature management component; 7-oil indicator; 8-communication component; 9-temperature sensor; 10-ball valve. Detailed Implementation

[0025] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0026] To enable those skilled in the art to better understand the present invention, the present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments.

[0027] This invention provides an immersion-type direct-cooled battery pack; please refer to the attached instruction manual. Figure 1 This application includes a housing 1 for accommodating various battery modules 4. A tray 3 is horizontally arranged inside the housing 1, dividing the housing 1 into two areas. Each battery module 4 is located below the tray 3. Several cooling pipes 5 are fixed on the side of the tray 3 opposite to each battery module 4. A refrigerant circulates within the cooling pipes 5. The refrigerant can absorb the heat generated by the battery modules 4 through phase change heat absorption and transfer the absorbed heat to the outside of the housing 1 through circulation. In one step, a certain volume of heat-conducting liquid is filled into the inner cavity of the housing 1. In addition, several flow holes 34 are evenly distributed on the end face of the tray 3 so that the filled heat-conducting liquid can overflow to the top of the tray 3 through the flow holes 34 after the battery module 4 is completely submerged, until each cooling pipe 5 is submerged. The battery module 4 located below the tray 3 achieves heat transfer with the cooling pipe 5 through the heat-conducting liquid. A top cover 2 is fixed at the port of the housing 1, and the top cover 2 seals the port of the housing 1 to ensure the airtightness of the cooling environment.

[0028] It should be noted that the main heat-generating area of ​​the battery module 4 during charging and discharging is the upper end, that is, the end close to the top cover 2. The lower end of the battery module 4 also generates heat, but the heat generation is relatively small. During the cooling process, after the upper end of the battery module 4 generates heat, the temperature of the heat-conducting liquid in this area rises after absorbing the heat, and the density of the heat-conducting liquid decreases. The heat-absorbing heat-conducting liquid floats up in the housing 1 and passes through the flow hole 34. At this time, the heat-absorbing heat-conducting liquid is located on one side of the cooling pipe 5. The refrigerant in the cooling pipe 5 absorbs heat and vaporizes, carrying the heat away from the housing 1 during the circulation process. After cooling, the density of the heat transfer fluid decreases, causing it to flow downwards. Since some heat is also generated below the battery module 4, the density of the heat transfer fluid in the lower area decreases to a certain extent. As the heat transfer fluid flows downwards, it drives the heat transfer fluid at the lower end of the battery module 4 to form convection, creating a circulation inside the housing 1. This ensures that the heat generated in each area of ​​the battery module 4 can be transported to the cooling pipe 5 by the heat transfer fluid, achieving temperature uniformity of the battery module 4. Furthermore, the circulating heat transfer fluid accelerates heat transfer and improves the cooling efficiency of this application.

[0029] Please refer to the instruction manual appendix. Figures 2 to 4 A temperature sensor 9 is installed between each battery module 4 and the tray 3. The temperature sensor 9 is used to collect the temperature of the upper part of each battery module 4. A temperature management component 6 is installed on the outer wall of the housing 1. The temperature management component 6 is signal connected to each battery module 4. The temperature management component 6 is used to receive the electrical signals sent by each temperature sensor 9. Furthermore, the temperature management component 6 is also signal connected to a communication component 8. The temperature management component 6 is adapted to send an electrical signal to the communication component 8 when the detected temperature of the battery module 4 is greater than a preset value. The communication component 8 then sends an operating signal to the direct cooling unit, and the direct cooling unit delivers refrigerant into the cooling pipe 5.

[0030] It should be noted that each cooling pipe 5 consists of two vertical pipes and three horizontal pipes. Each horizontal pipe is positioned along the width of the housing 1, and each vertical pipe is perpendicular to each horizontal pipe. A vertical pipe is positioned between each pair of adjacent horizontal pipes, with each vertical pipe located at one end of the length of a horizontal pipe, making each cooling pipe 5 S-shaped. Each cooling pipe 5 is made of copper, a material with excellent thermal conductivity. Connecting the cooling pipes end-to-end creates a serpentine cooling pipe assembly, ensuring that the heat absorption range of each cooling pipe 5 completely covers the tray 3. The separate arrangement of each cooling pipe 5 allows operators to adapt it according to the number and distribution of the battery modules 4 to be cooled, ensuring a good cooling environment for each battery module 4 while avoiding unnecessary cost losses. Furthermore, an L-shaped bend is connected to the end of the cooling pipe assembly, placing the end of the cooling pipe assembly on the same side of the tray 3 as the beginning, facilitating connection between the direct cooling unit and the inlet and outlet of the cooling pipe assembly.

[0031] Preferably, the spacing between the horizontal cooling pipes 5 is 72mm, the outer diameter of the horizontal and vertical pipes ranges from 6 to 8mm, and the pipe wall thickness ranges from 0.5 to 1mm.

[0032] Please refer to the instruction manual appendix. Figure 5 A plurality of flow holes 34 are provided on the end face of the tray 3. The flow holes 34 are evenly distributed on the tray 3 and are located between each horizontal pipe. The positions of the flow holes 34 and the cooling pipes 5 do not overlap, so as to avoid the cooling pipes 5 affecting the flow of the heat transfer fluid. In addition, a pipe groove 31 is provided on the tray 3. The extension shape of the pipe groove 31 is adapted to the cooling pipes 5, and the width of the pipe groove 31 is 1 to 1.5 mm, which makes the docking process between the cooling pipes 5 and the pipe groove 31 easier. Preferably, a plurality of pairs of cable tie holes 35 are provided on the tray 3. Each pair of cable tie holes 35 is symmetrically arranged on both sides of the pipe groove 31, and each pair of cable tie holes 35 is evenly distributed along the extension direction of the pipe groove 31. After the docking of the pipe groove 31 and the cooling pipes 5 is completed, cable ties are inserted into each pair of cable tie holes 35, and each cable tie is used to bind and fix the cooling pipes 5.

[0033] In addition, several fixing grooves 32 are provided between each cooling pipe 5. Each fixing groove 32 is used to set a buffer pad 33. The upper end of the buffer pad 33 extends out of the fixing groove 32 and abuts against the upper cover 2. The buffer pad 33 is used to absorb the vibration and impact that this application is subjected to during transportation.

[0034] An exhaust port 21 and a pressure relief valve 22 are provided on the side of the top cover 2 facing away from the battery module 4. Both the exhaust port 21 and the pressure relief valve 22 are connected to the inner cavity of the housing 1. When the heat-conducting liquid is injected into the housing 1, the exhaust port 21 is opened to balance the air pressure inside and outside the housing 1. The pressure relief valve 22 is opened periodically to release the air pressure caused by the heating of the battery module 4, and to prevent the battery module 4 from bulging due to charging and discharging.

[0035] Please continue to refer to the instruction manual appendix. Figure 2 The housing 1 includes a frame and a base plate. Two mounting beams 11 are fixedly connected inside the frame and are arranged along the width of the housing 1. The mounting beams 11 are used to fix each battery module 4. In addition, the temperature management component 6 is fixed to the inner wall of the frame. Two clamping connectors 13 are vertically inserted into the side wall of the frame. The clamping connector 13 includes a connector body, a front clamping sleeve, a rear clamping sleeve, and a nut. It should be noted that the beginning and end of the cooling pipe group extend to the outside of the housing 1. The beginning and end of the cooling pipe group are fitted with the connector body. Then, the front clamping sleeve, the rear clamping sleeve, and the nut are fitted in sequence at the port of the connector body. Then, the input and output ports of the direct cooling unit are inserted into the nut and the nut is tightened. The nut compresses and deforms the front and rear clamping sleeves to achieve a sealed connection of the input and output ports of the direct cooling unit to ensure that the refrigerant does not leak.

[0036] In addition, an oil level indicator 7 is provided on the side wall of the housing 1 where the compression fitting 13 is located. The oil level indicator 7 is used to observe the liquid level of the heat transfer fluid inside the housing 1. Correspondingly, a ball valve 10 is provided in the area of ​​the side wall of the housing 1 near the bottom plate. The ball valve 10 is connected to the inner cavity of the housing 1. The operator can inject or discharge the heat transfer fluid into the housing 1 through the ball valve 10. It should be noted that the ball valve 10, the communication component 8, each compression fitting 13 and the oil level indicator 7 are all located on the same end face of the frame.

[0037] Preferably, the frame is formed by bending and welding sheet metal or by integral stretching. The frame is welded and fixed to the base plate. The base plate is used to support each battery module 4, and a number of grooves 12 are provided on the side of the base plate facing the battery module 4. Each groove 12 is parallel to the mounting beam 11. During the cooling process of the battery module 4, the cooled heat transfer fluid flows downward and the heat transfer fluid flows upward through convection. In this cycle, each groove 12 serves as a channel for natural convection of the heat transfer fluid. At the same time, each groove 12 accelerates the flow of the high-temperature heat transfer fluid from the bottom to the top. In addition, the grooves 12 also increase the structural strength of the box 1 by changing the structure of the base plate, preventing the base plate from deforming due to the excessive weight of each battery module 4.

[0038] Preferably, the port edge of the housing 1 extends outward with a connecting plate, and each connecting plate is evenly provided with a number of fixing holes. Each connecting plate is used to support the upper cover 2, and fastening screws are inserted into each fixing hole to fix the upper cover 2 to the housing 1. A sealing strip is sandwiched between the upper cover 2 and the connecting plate, and the sealing strip further improves the sealing performance of this application.

[0039] It should be noted that in this specification, relational terms such as first and second are used only to distinguish one entity from several other entities, and do not necessarily require or imply any such actual relationship or order between these entities.

[0040] This article uses specific examples to illustrate the principles and implementation methods of the present invention. The descriptions of the above embodiments are only for the purpose of helping to understand the method and core ideas of the present invention. It should be noted that those skilled in the art can make several improvements and modifications to the present invention without departing from the principles of the present invention, and these improvements and modifications also fall within the protection scope of the present invention.

Claims

1. An immersion-type direct-cooled battery pack, characterized in that, include: The box (1) contains a number of battery modules (4) in its inner cavity. A tray (3) is fixed inside the box (1). A number of cooling pipes (5) are evenly distributed on the side of the tray (3) away from the battery modules (4). Cooling medium circulates in the cooling pipes (5). A number of flow holes (34) are evenly distributed on the tray (3). Each flow hole (34) connects the chambers on both sides of the tray (3). The inner cavity of the box (1) is filled with heat-conducting liquid. The heat-conducting liquid immerses each of the cooling pipes (5). A top cover (2) is provided at the port of the box (1). The top cover (2) seals the inner cavity of the box (1).

2. The immersion-type direct-cooled battery pack according to claim 1, characterized in that, Each of the battery modules (4) has a temperature sensor (9) fixed at one end near the tray (3). Each of the temperature sensors (9) is connected to a temperature management component (6). The temperature management component (6) is connected to a communication component (8). When the temperature sensor (9) detects that the temperature of the battery module (4) exceeds the preset value, the communication component (8) sends an operation signal to the direct cooling unit. The direct cooling unit is used to deliver the refrigerant into each of the cooling pipes (5).

3. The immersion-type direct-cooled battery pack according to claim 2, characterized in that, Each of the cooling pipes (5) is S-shaped and connected in series. The tray (3) has a groove (31) on the end face away from the battery module (4). Each of the cooling pipes (5) is fitted into the groove (31). Several pairs of cable tie holes (35) are symmetrically provided on both sides of the groove (31). Cable ties are inserted into the cable tie holes (35) to fix the cooling pipes (5).

4. The immersion-type direct-cooled battery pack according to claim 2, characterized in that, The tray (3) has a plurality of fixing grooves (32) evenly distributed on the end face facing the upper cover (2). Each fixing groove (32) is used to fix the buffer pad (33), and the buffer pad (33) abuts against the upper cover (2).

5. The immersion-type direct-cooled battery pack according to claim 2, characterized in that, The housing (1) includes a frame and a base plate. The inner cavity of the frame is fixedly connected to an installation beam (11). The installation beam (11) is used to fix each of the battery modules (4). The temperature management component (6) is fixed on the inner wall of the frame. The two ends of the series-connected cooling pipes (5) are connected to the input and output ports of the direct cooling unit through a compression fitting (13).

6. The immersion-type direct-cooled battery pack according to claim 5, characterized in that, The base plate is used to support each of the battery modules (4). Several grooves (12) are evenly distributed on the side end face of the base plate near the battery module (4). Each groove (12) is arranged parallel to the mounting beam (11).

7. The immersion-type direct-cooled battery pack according to claim 6, characterized in that, An oil level gauge (7) is provided on the side wall of the enclosure. The oil level gauge (7) is used to detect the liquid level of the heat-conducting liquid inside the box (1).

8. The immersion-type direct-cooled battery pack according to claim 7, characterized in that, A ball valve (10) is provided on the side edge of the frame near the bottom plate. The ball valve (10) is used for injecting or draining liquid into the tank (1). The ball valve (10), the communication component (8), each of the compression fittings (13) and the oil level indicator (7) are all located on the same side wall of the frame.

9. The immersion-type direct-cooled battery pack according to claim 1, characterized in that, The top cover (2) is provided with an exhaust port (21) and a pressure relief valve (22) on the side face away from the battery module (4). The pressure relief valve (22) and the exhaust port (21) are both connected to the inner cavity of the box body (1).

10. The immersion-type direct-cooled battery pack according to claim 2, characterized in that, The port edge of the box (1) extends outward with a connecting plate. Several fixing holes are evenly distributed on each connecting plate. Each connecting plate is used to support the top cover (2). Fastening screws are inserted in each fixing hole. Each fastening screw fixes the top cover (2) to the box (1). A sealing strip is sandwiched between the top cover (2) and the connecting plate.

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