Immersion liquid cooling device, energy storage system and thermal management method

Abstract

This application relates to the field of heat dissipation technology for energy storage systems, and discloses an immersion liquid cooling device, an energy storage system, and a thermal management method. The immersion liquid cooling device includes a housing, a fluid circulation structure, and a liquid level regulation structure. The housing has multiple liquid cooling spaces arranged sequentially and isolated from each other along a predetermined direction, each liquid cooling space accommodating a battery module. The fluid circulation structure is connected to the housing and includes an inlet pipe, a cross-flow pipe, and an outlet pipe. The inlet pipe supplies coolant, the cross-flow pipe transports coolant, and the outlet pipe discharges coolant. One of the two liquid cooling spaces furthest apart in the predetermined direction is connected to the inlet pipe, and the other is connected to the outlet pipe. Adjacent liquid cooling spaces are interconnected via the cross-flow pipe. The immersion liquid cooling device, energy storage system, and thermal management method provided in this application can effectively control the temperature of different battery modules in the energy storage system.

Description

Technical Field

[0001] The embodiments of the present application relate to the technical field of heat dissipation of energy storage systems, and in particular to an immersion liquid cooling device, an energy storage system, and a thermal management method. Background Art

[0002] With the continuous development of industrial technology, the demand for energy is increasing, and various new energy sources have been widely used in practice. The importance of energy storage is also gradually increasing. The energy storage system can store electrical energy through battery modules and output the stored electrical energy when needed. Since the energy storage system needs to be controlled at a suitable temperature during operation, it is necessary to dissipate heat from the energy storage system.

[0003] Energy storage systems usually contain a large number of battery modules. The temperature of these battery modules during operation affects the performance of the energy storage system. How to control the temperature of different battery modules in the energy storage system is an important issue. Summary of the invention

[0004] The purpose of the embodiments of the present application is to provide an immersion liquid cooling device, an energy storage system and a thermal management method, which can be helpful in controlling the temperature of different battery modules in the energy storage system.

[0005] In order to solve the above technical problems, an embodiment of the present application provides an immersion liquid cooling device. The immersion liquid cooling device includes a box, a fluid circulation structure and a liquid level adjustment structure. The box has a plurality of liquid cooling spaces arranged in sequence along a preset direction and isolated from each other, and each liquid cooling space is used to accommodate a battery module. The fluid circulation structure is connected to the box, and the fluid circulation structure includes a liquid inlet pipeline, a series flow pipeline and a liquid outlet pipeline. The liquid inlet pipeline is used to supply coolant, the series flow pipeline is used to transmit coolant, and the liquid outlet pipeline is used to discharge coolant. One of the two liquid cooling spaces farthest apart in the preset direction is connected to the liquid inlet pipeline, and the other is connected to the liquid outlet pipeline. The two adjacent liquid cooling spaces are connected to each other via the series flow pipeline. The liquid level adjustment structure is connected to the box, and the liquid level adjustment structure includes a shunt pipeline connecting each liquid cooling space, and also includes a fluid control unit and a plurality of fluid distribution units arranged on the shunt pipeline. The fluid distribution unit is arranged corresponding to the liquid cooling space, and is used to distribute cooling liquid to the liquid cooling space. The fluid control unit is used to control the amount of liquid distributed by the fluid distribution unit to the corresponding liquid cooling space to adjust the liquid level of the corresponding liquid cooling space.

[0006] The embodiment of the present application also provides an energy storage system, which includes a battery module and the above-mentioned immersion liquid cooling device. The battery module includes a plurality of battery cells arranged in sequence. Each liquid cooling space of the box of the immersion liquid cooling device accommodates at least one battery module.

[0007] The embodiment of the present application further provides a thermal management method applied to the above-mentioned immersion liquid cooling device, the thermal management method comprising:

[0008] The coolant enters each liquid cooling space of the box through the fluid circulation structure and is maintained at the initial liquid level;

[0009] Detect the temperature of the battery cells of the battery modules in each liquid cooling space;

[0010] If the temperature of the battery cells of the battery module in the liquid cooling space exceeds the threshold range, the coolant in the liquid cooling space is controlled by the fluid control unit to increase the liquid level under the distribution of the fluid distribution unit; if the temperature of the battery cells of the battery module in the liquid cooling space does not exceed the threshold range, the coolant in the liquid cooling space is maintained at the initial liquid level.

[0011] The immersion liquid cooling device, energy storage system and thermal management method provided by the embodiments of the present application are provided with a plurality of liquid cooling spaces in the box, and each liquid cooling space can accommodate different battery modules. Each liquid cooling space is connected to the coolant circulation system through a fluid circulation structure, and the coolant can enter the box through a liquid inlet pipeline, and continuously circulate in each liquid cooling space through a series flow pipeline to reach a certain immersion liquid level height. During the circulation process, the coolant takes away the heat of each battery cell of the battery module, thereby achieving sufficient heat dissipation of different battery modules. In addition, the liquid level height of the immersion coolant in the liquid cooling space where different battery modules are located can be adjusted by cooperating with the fluid control unit and the fluid distribution unit, thereby adjusting the heat dissipation capacity of the liquid cooling space where different battery modules are located. Then, the temperature of different battery modules in the energy storage system is controlled.

[0012] In some embodiments, the liquid inlet pipeline and the liquid outlet pipeline are arranged on one side or both sides of the box along the first direction, and the first direction is perpendicular to the arrangement direction of the multiple battery cells in the battery module. In this way, by arranging the liquid inlet pipeline and the liquid outlet pipeline on one side or both sides of the box along the first direction, the coolant can flow in and out along the arrangement direction of the multiple battery cells in the battery module, ensuring the heat dissipation effect of the multiple battery cells in the battery module.

[0013] In some embodiments, there are multiple series flow pipelines, each of which connects two adjacent liquid cooling spaces in a preset direction, and multiple series flow pipelines are alternately arranged on both sides of the box along the first direction along the preset direction. In this way, by alternately arranging multiple series flow pipelines on both sides of the box along the first direction, the coolant can flow in a serpentine unidirectional manner in multiple liquid cooling spaces, ensuring that the coolant sequentially takes away the heat of the battery modules in each liquid cooling space.

[0014] In some embodiments, there are multiple inlet pipelines, multiple outlet pipelines, and multiple serial flow pipelines connecting the two liquid cooling spaces, and the multiple inlet pipelines, multiple outlet pipelines, and multiple serial flow pipelines connecting the two liquid cooling spaces are arranged at intervals along the first direction. In this way, by increasing the number of pipelines in the fluid circulation structure, the flow path of the coolant can be increased, ensuring the stable flow of the coolant.

[0015] In some embodiments, the box includes a bracket, a cavity wall is formed on the bracket to form a closed space, and a separator is formed in the closed space to form a plurality of liquid cooling spaces, and the bracket is provided with a plurality of platforms corresponding to the plurality of liquid cooling spaces, each platform has a hollow area, and each platform is used to support the battery module and separate the battery module from the separator. In this way, the bottom of the battery module can be in contact with the immersed coolant for heat exchange through the platform with the hollow area formed by the bracket, thereby improving the heat dissipation effect of the coolant.

[0016] In some embodiments, the bracket includes a plurality of pillars abutting against the cavity wall, a plurality of connecting rod assemblies arranged in sequence along a preset direction and connecting the plurality of pillars together, and an intermediate rod assembly arranged corresponding to the liquid cooling space and connected to the connecting rod assembly, each intermediate rod assembly includes a plurality of intermediate rods arranged at intervals and used to support the battery module, and the extension direction of the intermediate rod is parallel to the arrangement direction of the plurality of battery cells in the battery module. In this way, the bracket can be formed by adopting a frame structure to ensure that the bottom of the battery module can fully contact with the coolant for heat exchange, and the heat dissipation capacity of the battery module can be ensured while stably supporting the battery module.

[0017] In some embodiments, the bracket further includes a reinforcing rib assembly arranged corresponding to the liquid cooling space and connected to the middle rod assembly, each reinforcing rib assembly includes a plurality of reinforcing ribs arranged at intervals, and each reinforcing rib does not protrude from the middle rod in a preset direction. In this way, the structural strength of the bracket platform can be improved by the reinforcing ribs, and the placement of the battery module can be avoided from being affected.

[0018] In some embodiments, the fluid circulation structure further includes a liquid replenishing pipeline, and the liquid replenishing pipeline and the liquid inlet pipeline are connected to the same liquid cooling space. In this way, the coolant can be replenished and supplied through the liquid replenishing pipeline, effectively increasing the total capacity of the coolant circulating in the box to improve the heat dissipation capacity of the coolant. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] One or more embodiments are exemplarily described by pictures in the corresponding drawings, and these exemplified descriptions do not constitute limitations on the embodiments. Elements with the same reference numerals in the drawings represent similar elements, and unless otherwise stated, the figures in the drawings do not constitute proportional limitations.

[0020] Figure 1is a schematic diagram of the three-dimensional structure of an energy storage system provided in some embodiments of the present application;

[0021] Figure 2 is a right-side structural schematic diagram of an energy storage system provided in some embodiments of the present application;

[0022] Figure 3 is a schematic diagram of the internal structure of an energy storage system provided in some embodiments of the present application;

[0023] Figure 4 is a schematic diagram of the arrangement structure of battery modules in an energy storage system provided in some embodiments of the present application;

[0024] Figure 5 is a schematic diagram of a three-dimensional structure of a bracket in an energy storage system provided in some embodiments of the present application;

[0025] Figure 6 It is a flow chart of a thermal management method for an immersion liquid cooling device in an energy storage system provided in some embodiments of the present application. DETAILED DESCRIPTION

[0026] To make the purpose, technical scheme and advantages of the embodiments of the present application clearer, each embodiment of the present application will be described in detail below in conjunction with the accompanying drawings. However, it will be appreciated by those skilled in the art that in each embodiment of the present application, many technical details are proposed in order to enable the reader to better understand the present application. However, even without these technical details and various changes and modifications based on the following embodiments, the technical scheme claimed in the present application can also be implemented. The division of the following embodiments is for the convenience of description, and the specific implementation of the present application should not constitute any limitation, and the various embodiments can be combined with each other and referenced to each other without contradiction.

[0027] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by technicians in the technical field to which this application belongs; the terms used herein are only for the purpose of describing specific embodiments and are not intended to limit this application; the terms "including" and "having" in the specification and claims of this application and the above-mentioned figure descriptions and any variations thereof are intended to cover non-exclusive inclusions.

[0028] In the description of the embodiments of the present application, unless otherwise clearly specified and limited, technical terms such as "installed", "connected", "connected" and the like should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium, and it can be the internal connection of two elements or the interaction relationship between two elements. For ordinary technicians in this field, the specific meanings of the above terms in the embodiments of the present application can be understood according to the specific circumstances.

[0029] The effective use of energy is inseparable from the energy storage system, which can effectively store the electric energy converted by the power generation system and release the stored electric energy when the power consumption system needs it. The energy storage system can avoid the waste of electric energy converted by the power generation system during the low power consumption period, and avoid the power consumption system from insufficient power supply during the peak power consumption period. The battery module in the energy storage system contains a large number of battery cells. By connecting a large number of battery cells in series or in parallel, as much energy as possible can be stored.

[0030] At present, most energy storage systems use liquid cooling plates for cooling. However, due to the limitation of the heat dissipation capacity of the liquid cooling plates, the battery modules generally have problems such as uneven temperature distribution of the internal cells and excessive temperature rise of some cells. These problems greatly reduce the working efficiency of the energy storage system. Therefore, it is necessary to design a new heat dissipation form for the energy storage system.

[0031] In order to control the temperature of different battery modules in the energy storage system, some embodiments of the present application provide an immersion liquid cooling device. The immersion liquid cooling device adopts a cluster-level immersion liquid cooling form, and different battery modules are immersed in the coolant. The battery cells of the battery modules can fully contact with the coolant to exchange heat and achieve heat dissipation. In addition, the liquid level height of the immersion coolant corresponding to the battery module can be adjusted, so as to adjust the heat dissipation capacity by adjusting the liquid level height of the immersion coolant of different battery modules to control the temperature of different battery modules.

[0032] Combine the following Figures 1 to 5 The structure of an immersion liquid cooling device in an energy storage system provided in some embodiments of the present application is described.

[0033] like Figures 1 to 5 As shown, the immersion liquid cooling device provided in some embodiments of the present application includes a box 11, a fluid circulation structure 12 and a liquid level adjustment structure 13. The box 11 has a predetermined direction ( Figure 1A plurality of liquid cooling spaces 101 are sequentially arranged and isolated from each other (in the direction indicated by the arrow Z in the middle), and each liquid cooling space 101 is used to accommodate a battery module 21. The fluid circulation structure 12 is connected to the housing 11, and the fluid circulation structure 12 includes a liquid inlet pipeline 121, a series flow pipeline 122, and a liquid outlet pipeline 123. The liquid inlet pipeline 121 is used to supply the coolant, the series flow pipeline 122 is used to transmit the coolant, and the liquid outlet pipeline 123 is used to discharge the coolant. One of the two liquid cooling spaces 101 farthest apart in the preset direction is connected to the liquid inlet pipeline 121, and the other is connected to the liquid outlet pipeline 123. The two adjacent liquid cooling spaces 101 are connected to each other via the series flow pipeline 122. The liquid level adjustment structure 13 is connected to the housing 11, and the liquid level adjustment structure 13 includes a shunt pipeline 131 connecting each liquid cooling space 101, and also includes a fluid control unit 132 and a plurality of fluid distribution units 133 arranged on the shunt pipeline 131. The fluid distribution unit 133 is arranged corresponding to the liquid cooling space 101. The fluid distribution unit 133 is used to distribute cooling liquid to the liquid cooling space 101. The fluid control unit 132 is used to control the amount of liquid distributed by the fluid distribution unit 133 to the corresponding liquid cooling space 101 to adjust the liquid level of the corresponding liquid cooling space 101.

[0034] The box 11 provides a storage space for the energy storage system, and different battery modules 21 can be fixed at different positions inside the box 11. In order to form immersion liquid cooling for different battery modules 21, a plurality of liquid cooling spaces 101 are provided inside the box 11, and each liquid cooling space 101 is in a relatively closed state. After the coolant enters the liquid cooling space 101, it can partially or completely immerse the battery module 21. In the immersed state of the coolant, the battery cell 211 of the battery module 21 can be in full contact with the coolant to achieve heat dissipation. Each liquid cooling space 101 can accommodate one or more battery modules 21, and the plurality of liquid cooling spaces 101 are arranged in sequence along a preset direction, and the preset direction can be a vertical direction or a horizontal direction, or other directions having an angle with the vertical direction. In actual situations, the plurality of liquid cooling spaces 101 can be arranged in layers, or separated. The overall shape of the box 11 can be set to a regular shape such as a cube, a cuboid or a cylinder, or to an irregular shape of a special shape. The liquid cooling space 101 in the box 11 can be in a regular shape such as a cube, a cuboid or a column, or in an irregular shape.

[0035] The fluid circulation structure 12 is used to facilitate the access of the internal space of the housing 11 to the coolant circulation system. The fluid circulation structure 12 includes an inlet pipeline 121 for inputting coolant into the liquid cooling space 101 of the housing 11, a series flow pipeline 122 for transmitting coolant between two adjacent liquid cooling spaces 101, and an outlet pipeline 123 for discharging coolant. The end of the inlet pipeline 121 exposed from the housing 11 can be connected to a pipeline for supplying coolant, and the other end of the inlet pipeline 121 is connected to one of the two liquid cooling spaces 101 farthest apart in a preset direction. The end of the outlet pipeline 123 exposed from the housing 11 can be connected to a pipeline for recovering coolant, and the other end of the outlet pipeline 123 is connected to the other of the two liquid cooling spaces 101 farthest apart in a preset direction. The two ends of the series flow pipeline 122 are connected to two adjacent liquid cooling spaces 101 respectively, and the multiple liquid cooling spaces 101 are connected to each other via the series flow pipeline 122, so that each liquid cooling space 101 of the box body 11 is connected to the circulating coolant. In actual situations, multiple liquid cooling spaces 101 can be connected in sequence via the series flow pipeline 122, so that the coolant flows in multiple liquid cooling spaces 101 in sequence. Or when the number of liquid cooling spaces 101 is large, some liquid cooling spaces 101 can be connected to more than two other liquid cooling spaces 101 at the same time, so that the coolant is distributed to more than two liquid cooling spaces 101 at the same time during the flow process. The connection position of each pipeline of the fluid circulation structure 12 on the box body 11 can be set according to actual needs. In order to ensure the flow effect of the coolant in each liquid cooling space 101, the connection position of each pipeline can be close to the bottom position of the corresponding liquid cooling space 101.

[0036] The liquid level regulating structure 13 is used to adjust the liquid level height of the coolant immersed in each liquid cooling space 101 of the housing 11. The liquid level regulating structure 13 includes a shunt pipeline 131 that is simultaneously connected to each liquid cooling space 101, and a fluid control unit 132 is provided on the shunt pipeline 131, and a fluid distribution unit 133 corresponding to the multiple liquid cooling spaces 101. The fluid distribution unit 133 can control the flow rate of the coolant circulating at the location, and the fluid control unit 132 can control the active flow of the coolant. The fluid distribution unit 133 can be a solenoid valve, a throttle valve or a flow control valve that can adjust the opening size, and the fluid control unit 132 can be various types of water pumps, such as a volumetric pump, a vane pump or a centrifugal pump.

[0037] When the energy storage system detects that the temperature of the battery cell 211 of a certain battery module 21 is too high, the liquid level of the immersion coolant in the liquid cooling space 101 where the battery module 21 is located can be actively adjusted through the liquid level adjustment structure 13, so that the liquid level of the coolant in the liquid cooling space 101 where the battery module 21 is located rises. This improves the heat dissipation capacity in the liquid cooling space 101 and controls the temperature of the battery cell 211 of the battery module 21 to remain within a reasonable range.

[0038] The immersion liquid cooling device provided in some embodiments of the present application has multiple liquid cooling spaces 101 arranged in the box 11, and each liquid cooling space 101 can accommodate different battery modules 21. Each liquid cooling space 101 is connected to the cooling liquid circulation system through the fluid circulation structure 12, and the cooling liquid can enter the box 11 through the liquid inlet pipeline 121, and continuously circulate in each liquid cooling space 101 through the series flow pipeline 122 to reach a certain immersion liquid level height. During the circulation process, the cooling liquid takes away the heat of each battery cell 211 of the battery module 21, thereby achieving sufficient heat dissipation of different battery modules 21. In addition, the liquid level height of the immersion cooling liquid in the liquid cooling space 101 where different battery modules 21 are located can be adjusted by cooperating with the fluid control unit 132 and the fluid distribution unit 133, thereby adjusting the heat dissipation capacity of the liquid cooling space 101 where different battery modules 21 are located. Then the temperature of different battery modules 21 in the energy storage system is controlled.

[0039] In some embodiments, the liquid inlet pipeline 121 and the liquid outlet pipeline 123 can be arranged on the housing 11 along the first direction ( Figure 1 The first direction is perpendicular to the arrangement direction of the plurality of battery cells 211 in the battery module 21 ( Figure 1 direction indicated by arrow X).

[0040] The liquid inlet pipeline 121 controls the flow of the cooling liquid into the liquid cooling space 101 in the box 11, and the liquid outlet pipeline 123 controls the discharge of the cooling liquid from the liquid cooling space 101 in the box 11. By locating the liquid inlet pipeline 121 and the liquid outlet pipeline 123 on one side or both sides of the box 11 along the first direction, the flow direction of the cooling liquid when entering and discharging can be made consistent with the arrangement direction of the multiple battery cells 211 in the battery module 21, thereby controlling the cooling liquid to flow in the box 11 along the arrangement direction of the multiple battery cells 211 in the battery module 21. This ensures the heat dissipation effect of each battery cell 211 in the battery module 21.

[0041] When the number of liquid cooling spaces 101 is an even number, the liquid inlet pipeline 121 and the liquid outlet pipeline 123 can be arranged on the same side of the housing 11. When the number of liquid cooling spaces 101 is an odd number, the liquid inlet pipeline 121 and the liquid outlet pipeline 123 can be arranged on both sides of the housing 11. Figure 3 As shown, the box body 11 is provided with four liquid cooling spaces 101, the liquid inlet pipeline 121 and the liquid outlet pipeline 123 are arranged on the same side of the box body 11, and the liquid inlet pipeline 121 and the liquid outlet pipeline 123 are connected to one end of the liquid cooling space 101 facing two larger surfaces of the battery cells 211 in the battery module 21, that is, towards the arrangement direction of the multiple battery cells 211.

[0042] In actual situations, when two adjacent liquid cooling spaces 101 are connected, in order to make the coolant fully contact with each battery cell 211 in the battery module 21 and flow smoothly in each liquid cooling space 101, the end of the series flow pipeline 122 receiving the coolant can be set at the tail of the coolant flow in the liquid cooling space 101, and the end of the series flow pipeline 122 outputting the coolant can be set at the head of the coolant flow in the liquid cooling space 101. In addition, when each liquid cooling space 101 is arranged in layers, the liquid inlet pipeline 121 can be connected to the top position of the box body 11, and the liquid outlet pipeline 123 can be connected to the bottom position of the box body 11, so that the coolant can flow smoothly through each liquid cooling space 101 of the box body 11 under the action of gravity.

[0043] In addition, there may be multiple serial flow pipelines 122, each serial flow pipeline 122 connects two adjacent liquid cooling spaces 101 in a preset direction, and multiple serial flow pipelines 122 are alternately arranged on both sides of the box 11 along the first direction along the preset direction.

[0044] When the number of liquid cooling spaces 101 provided in the housing 11 exceeds two, the multiple liquid cooling spaces 101 can be interconnected through more than two series flow pipes 122. Every two adjacent liquid cooling spaces 101 can be connected through a series flow pipe 122, and the multiple series flow pipes 122 are alternately arranged on both sides of the housing 11 along the first direction in a preset direction. In this way, the multiple liquid cooling spaces 101 are connected end to end, and after the coolant enters the housing 11, it can flow in the housing 11 in the form of a serpentine flow channel, thereby achieving full contact with each battery module 21, and effectively taking away the heat of the battery cell 211 in each battery module 21.

[0045] In some embodiments, there are multiple liquid inlet pipelines 121, multiple liquid outlet pipelines 123, and multiple serial flow pipelines 122 connecting the two liquid cooling spaces 101, and the multiple liquid inlet pipelines 121, multiple liquid outlet pipelines 123, and multiple serial flow pipelines 122 connecting the two liquid cooling spaces 101 are all arranged at intervals along the first direction.

[0046] The liquid cooling space 101 in the box 11 usually has a large volume to accommodate one or more battery modules 21. The battery modules 21 can be arranged in parallel or in succession in the liquid cooling space 101, or arranged in an array. In order to adapt to the size of the space in the box 11, the number of each pipeline in the fluid circulation structure 12 can be increased, and the liquid inlet pipeline 121, the liquid outlet pipeline 123, and the series flow pipeline 122 connecting the two liquid cooling spaces 101 are all set to multiple. In addition, the multiple liquid inlet pipelines 121, the multiple liquid outlet pipelines 123, and the multiple series flow pipelines 122 connecting the two liquid cooling spaces 101 in the fluid circulation structure 12 are arranged at intervals along the first direction, that is, arranged along the side-by-side direction of the multiple battery modules 21. Thereby, the coolant circulating in the liquid cooling space 101 can fully immerse the area where the different battery modules 21 are located, and achieve uniform heat dissipation of each battery module 21 located in the same liquid cooling space 101. At the same time, it is ensured that sufficient cooling liquid can continuously flow into the liquid cooling space 101 of the box 11. In actual situations, the number of pipelines in the fluid circulation structure 12 can be consistent with the number of battery modules 21 arranged side by side in each liquid cooling space 101. For example, Figure 3 and Figure 4 Each liquid cooling space 101 of the box 11 shown in the figure can accommodate four battery modules 21 placed side by side, and the fluid circulation structure 12 can be provided with four corresponding liquid inlet pipelines 121, four liquid outlet pipelines 123, and four series flow pipelines 122 connecting the two liquid cooling spaces 101. There is a gap between two adjacent battery modules 21, and the coolant can flow along the side of each battery module 21 to take away the heat of each battery module 21.

[0047] In addition, when the battery module 21 is arranged in the liquid cooling space 101 in the box 11, a certain space can be reserved at the bottom of the battery module 21. After the coolant enters the liquid cooling space 101, it can contact the bottom of the battery module 21, thereby ensuring the contact area between the coolant and each battery cell 211 in the battery module 21, and realizing effective heat transfer. That is, the battery module 21 can be placed by providing a platform 102 with a hollow area.

[0048] In some embodiments, the housing 11 may include a bracket 111, a cavity wall 112 is arranged on the bracket 111 to form a closed space, and an isolation member 113 is provided to separate the closed space into a plurality of liquid cooling spaces 101. The bracket 111 is provided with a plurality of platforms 102 corresponding to the plurality of liquid cooling spaces 101, each platform 102 having a hollow area, and each platform 102 is used to support the battery module 21 and separate the battery module 21 from the isolation member 113.

[0049] The bracket 111 is used to form a platform 102 in the box body 11 for placing the battery module 21. The bracket 111 as a whole can be a frame-type component, which is made in the form of splicing and assembly. In order to ensure the structural strength of the bracket 111, the bracket 111 can be made of metal material. The cavity wall 112 is set on the outer contour of the bracket 111. The cavity wall 112 can be used to enclose the internal accommodating space of the box body 11, so that the battery module 21 is in a relatively closed environment relative to the outside world. The isolation member 113 divides the closed space surrounded by the cavity wall 112 into a plurality of liquid-cooling spaces 101. The isolation member 113 can be in the form of a flat plate. The isolation member 113 can be connected and fixed to the cavity wall 112 or the bracket 111. The isolation member 113 is used to keep each liquid-cooling space 101 in a relatively closed state, such as Figure 5 As shown, isolation members 113 are provided on the second platform 102, the third platform 102 and the fourth platform 102 from top to bottom of the bracket 111. The three isolation members 113 cooperate with the cavity wall 112 to form four relatively closed liquid cooling spaces 101. The relatively closed liquid cooling spaces 101 are connected through the series flow pipeline 122 to form a complete cooling liquid flow channel.

[0050] The platform 102 provided on the bracket 111 corresponds to the liquid cooling space 101, and each platform 102 has a hollow area. When the battery module 21 is fixed on the platform 102, the bottom of the battery module 21 can be kept in a spaced state with the spacer 113. In this way, the coolant can enter the hollow area of ​​the platform 102 so as to fully contact the bottom of the battery module 21. At the same time, the coolant can keep in contact with the battery module 21 on the side of the battery module 21. Thus, the bottom and both sides of the battery module 21 can be in contact with the immersed coolant for heat exchange. In actual situations, when the battery module 21 is fixed, it can be connected to the bracket 111 by a long bolt. The long bolt can pass through the outermost end plate 212 of the battery module 21 and be fixed on the bracket 111, thereby completing the fixation of the battery module 21. There can be a gap between two adjacent cells 211 of the battery module 21 so that the coolant can be in contact with the cell 211 around the cell 211 for heat exchange.

[0051] In some embodiments, a channel for cooling liquid to flow may be provided inside the cavity wall 112 of the box body 11, so that the cavity wall 112 surrounding the entire bracket 111 also has heat absorption capability. Figure 3The six cavity walls 112 of the box body 11 shown in the figure facing different directions can all be provided with hollow channels, and coolant can be input into the channels so that the coolant can circulate inside the cavity wall 112 to take away the heat transferred to the cavity wall 112. In order to extend the flow path of the coolant and achieve sufficient heat absorption of the coolant, the channel can be set to a curved shape. In actual situations, efficient heat dissipation components such as heat pipes can also be embedded on the surface or inside of the cavity wall 112, so that the heat transferred from the coolant in the liquid-cooled space 101 to the cavity wall 112 can be promptly conducted to the outside world, thereby improving the heat dissipation capacity of the battery module 21. The heat pipe can be in contact with the cavity wall 112 and the outside world as a whole in the length direction, or one end passes through the cavity wall 112 to contact the coolant in the liquid-cooled space 101, and the other end is in contact with the outside world.

[0052] In addition, a channel for the flow of coolant can be provided on the side surface of the separator 113 that carries the coolant. For example, an inwardly recessed groove can be provided on the surface of the separator 113, and the groove can have a cross-sectional shape such as a triangle, a square or a rectangle. The coolant can flow along the groove to reach a specific position in the liquid cooling space 101. This is conducive to ensuring the flow effect of the coolant at the bottom of the battery module 21. At the same time, in order to enhance the heat exchange effect of the coolant, the groove can be set to extend in a curved path. Thereby extending the flow path of the coolant and fully absorbing the heat of the battery module 21.

[0053] In addition, if Figure 4 and Figure 5 As shown, the bracket 111 may include a plurality of pillars 1111 abutting against the cavity wall 112, a plurality of connecting rod assemblies 1112 arranged in sequence along a preset direction and connecting the plurality of pillars together, and an intermediate rod assembly 1113 arranged corresponding to the liquid cooling space 101 and connected to the connecting rod assembly 1112, each intermediate rod assembly 1113 includes a plurality of intermediate rods arranged at intervals for supporting the battery module 21, and an extension direction of the intermediate rods is parallel to an arrangement direction of the plurality of battery cells 211 in the battery module 21.

[0054] The pillars 1111 form the outer contour of the bracket 111, are supported on the inner side of the cavity wall 112 close to the closed space, and are kept in contact with the cavity wall 112. Each pillar 1111 extends along a preset direction, and multiple pillars 1111 are connected together by a connecting rod assembly 1112. The connecting rod assembly 1112 in the middle position in the preset direction is located on the top of the isolation member 113. The multiple connecting rods of the connecting rod assembly 1112 can be connected end to end to connect and fix the multiple pillars 1111 in a circle. This ensures the strength of the formed frame-type structure.

[0055] The intermediate rod assembly 1113 is arranged corresponding to the liquid cooling space 101, and both ends of each intermediate rod of the intermediate rod assembly 1113 are connected to different connecting rods in the connecting rod assembly 1112. In addition, the multiple intermediate rods of the intermediate rod assembly 1113 are arranged at intervals, and when supporting the battery module 21, they only contact part of the battery module 21. Thus, a large hollow area is formed at the bottom of the battery module 21, which facilitates the cooling liquid to be filled at the bottom of the battery module 21 as much as possible.

[0056] In some embodiments, a heat transfer component may be provided on the middle rod assembly 1113 of the bracket 111, and the heat transfer component is made of a heat conductive material. The heat transfer component may be provided in a regular shape such as a cylinder, a cube or a cuboid, or in an irregular shape. The heat transfer component may be provided in an island shape on each platform 102, and extend through the isolation member 113 to the liquid cooling space 101 corresponding to another platform 102. In order to achieve heat transfer in different liquid cooling spaces 101 through the heat conduction of the heat transfer component, the heat dissipation balance of the coolant in different liquid cooling spaces 101 is ensured.

[0057] like Figure 5 As shown, the bracket 111 may also include a reinforcing rib assembly 1114 arranged corresponding to the liquid cooling space 101 and connected to the middle rod assembly 1113, each reinforcing rib assembly 1114 includes a plurality of reinforcing ribs arranged at intervals, and each reinforcing rib does not protrude from the middle rod in a preset direction.

[0058] The reinforcing rib assembly 1114 can reinforce the structural strength of each platform 102 of the bracket 111, and improve the supporting capacity of each platform 102 for the battery module 21. Each reinforcing rib of the reinforcing rib assembly 1114 can connect two adjacent middle bars of the middle bar assembly 1113, and connect multiple middle bars in the middle bar assembly 1113 to form a whole. The extension direction of the reinforcing rib can be perpendicular to the extension direction of the middle bar.

[0059] Each reinforcing rib is flush with the middle rod or lower than the middle rod. By making the reinforcing rib not protrude from the middle rod, it is possible to avoid affecting the fixation of the battery module 21 on the platform 102. In addition, when the structural strength of the reinforcing rib is sufficient, a gap can be left between the reinforcing rib and the battery module 21 to facilitate the immersion coolant to enter the bottom of the battery module 21 and contact with the battery module 21 for heat exchange.

[0060] In addition, the reinforcing rib assembly 1114 may include a first reinforcing rib and a second reinforcing rib, and the first reinforcing rib and the second reinforcing rib may extend in different directions. By providing reinforcing ribs extending in different directions, the structural strength of each platform 102 can be strengthened from different directions. In actual situations, the first reinforcing rib and the second reinforcing rib may remain separated, or they may be connected to each other to form a whole. Moreover, the distance between the reinforcing ribs may be varied to adapt to the amount of coolant filling in different areas of the same liquid-cooled space 101, and to optimize the heat dissipation capacity in different areas of the same liquid-cooled space 101. For example, in the tail area where the coolant flows in the liquid-cooled space 101, the number of reinforcing ribs arranged may be reduced, and a larger filling space may be provided for the coolant. So that there is sufficient coolant filled at the bottom of the battery module 21 to ensure the heat dissipation capacity of the coolant at the end of the flow path.

[0061] In some embodiments, Figure 1 As shown, the fluid circulation structure 12 may further include a liquid replenishing pipeline 124 , and the liquid replenishing pipeline 124 and the liquid inlet pipeline 121 are connected to the same liquid cooling space 101 .

[0062] The refill line 124 can also be connected to the line for supplying coolant in the coolant circulation system, so as to introduce coolant into the liquid cooling space 101. The refill line 124 provides an independent channel for the coolant to enter the liquid cooling space 101 in the housing 11. The refill line 124 can be used to replenish coolant into the liquid cooling space 101, thereby increasing the amount of coolant entering the liquid cooling space 101. For example, when the temperature of the battery cell 211 of the battery module 21 contained in the housing 11 exceeds the threshold range to a certain value, the coolant can be replenished through the refill line 124. Thus, on the basis of the total capacity of the coolant currently circulating in the housing 11, a certain amount of coolant is additionally introduced to improve the heat dissipation capacity. In addition, the flow rate of the coolant can be increased by increasing the rate of fluid circulation to timely remove higher heat.

[0063] like Figure 1 As shown, the flow-dividing pipeline 131 and the flow-sequential pipeline 122 may be located at different sides of the housing 11 .

[0064] The flow distribution pipeline 131 and the flow series pipeline 122 are arranged on different sides of the housing 11, which can reduce the mutual interference between the fluid circulation structure 12 and the liquid level adjustment structure 13 and avoid the influence of the liquid level fluctuation in each liquid cooling space 101. Figure 1 and Figure 2As shown, the shunt pipeline 131 is connected to the surface of the box 11 with a larger area. The shunt pipeline includes a main pipeline and a plurality of branch pipelines. The main pipeline is arranged on one side of the box 11 along a preset direction. One end of the plurality of branch pipelines is connected to the main pipeline, and the other end of the plurality of branch pipelines is connected to the corresponding liquid cooling space 101. A fluid distribution unit 133 is arranged on each branch pipeline. The fluid control unit 132 is arranged on the main pipeline. The series flow pipeline 122 is connected to the surface of the box 11 with a smaller area. In actual situations, the shunt pipeline 131 and the series flow pipeline 122 can be placed away from each other to ensure the accuracy of the liquid level adjustment.

[0065] Some embodiments of the present application also provide an energy storage system, which includes a battery module 21 and the above-mentioned immersion liquid cooling device. The battery module 21 includes a plurality of battery cells 211 arranged in sequence. Each liquid cooling space 101 of the box 11 of the immersion liquid cooling device accommodates at least one battery module 21.

[0066] A plurality of battery modules 21 are fixed in the box 11 to form an energy storage system, and each liquid cooling space 101 of the box 11 can accommodate at least one battery module 21. The temperature of each battery cell 211 of the battery module 21 can be monitored by setting a thermocouple at the pole, and the temperature of each battery cell 211 can be controlled by immersing the battery cell 211 in the coolant. The immersion coolant can fully contact each battery cell 211 to exchange heat, and timely remove the heat generated during the operation of the battery cell 211, so as to achieve effective heat dissipation of the battery module 21.

[0067] In addition, if Figure 4 As shown, a heat insulating material 213 may be disposed between two adjacent battery cells 211 of the battery module 21 .

[0068] The heat insulating material 213 may be filled between two adjacent battery cells 211 to prevent the two adjacent battery cells 211 from influencing each other due to contact with each other, and to prevent heat from being transferred between the two adjacent battery cells 211, thereby preventing the temperature control of each battery cell 211 from being affected.

[0069] like Figure 6 As shown, some embodiments of the present application also provide a thermal management method applied to the above-mentioned immersion liquid cooling device, and the thermal management method includes the following steps:

[0070] Step S100 , coolant enters each liquid cooling space 101 of the box body 11 through the fluid circulation structure 12 and is maintained at an initial liquid level.

[0071] The initial liquid level may be 50% of the maximum height in the liquid cooling space 101 , that is, the liquid cooling space 101 is semi-immersed, so that the liquid level of the coolant can be adjusted later according to the temperature of the battery cell 211 .

[0072] Step S200 , detecting the temperature of the battery cell 211 of the battery module 21 in each liquid cooling space 101 .

[0073] The temperature of the battery cell 211 can be detected by a temperature monitoring element on the battery cell 211. For example, a thermocouple can be set at the pole of the battery cell 211 to obtain the temperature of the battery cell 211 through the thermocouple, so as to perform subsequent liquid level adjustment.

[0074] Step S300: If the temperature of the battery cell 211 of the battery module 21 in the liquid cooling space 101 exceeds the threshold range, the coolant in the liquid cooling space 101 is controlled by the fluid control unit 132 to increase the liquid level under the distribution of the fluid distribution unit 133; if the temperature of the battery cell 211 of the battery module 21 in the liquid cooling space 101 does not exceed the threshold range, the coolant in the liquid cooling space 101 is maintained at the initial liquid level.

[0075] That is, when the temperature of the battery cell 211 exceeds the threshold range, the liquid level of the immersion coolant in the liquid cooling space 101 where the battery module 21 is located can be increased to improve the heat dissipation capacity in the liquid cooling space 101 and promptly remove the heat of the battery cell 211. When the temperature of the battery cell 211 does not exceed the threshold range, that is, is within a reasonable range, the coolant in the liquid cooling space 101 can be maintained at the initial liquid level.

[0076] In actual situations, Figure 1 Taking the immersion liquid cooling device in the energy storage system shown in as an example, the liquid level height of the coolant immersed in each liquid cooling space 101 in the box 11 is set to half immersion, that is, 50% of the maximum height of the liquid cooling space 101. After the battery module 21 starts charging and discharging, the coolant flows into the box 11 from the liquid inlet pipeline 121, and the one-way flow heat exchange of the coolant in each liquid cooling space 101 is realized through the series flow pipeline 122. Based on the fact that the heat dissipation capacity of the coolant gradually decreases as the coolant continuously absorbs heat during the flow, the following control strategy can be executed according to the temperature monitoring data of the battery cell 211:

[0077] (1) When the maximum temperature difference between the battery cells 211 of the two battery modules 21 in the box body 11 is less than 2°C (degrees Celsius), the fluid control unit 132 and the multiple fluid distribution units 133 of the liquid level adjustment structure 13 do not distribute the fluid, and the cooling liquid immersion height in the multiple liquid cooling spaces 101 remains unchanged.

[0078] (2) When the maximum temperature difference between the battery cells 211 of the two battery modules 21 in the box body 11 is greater than 2°C and less than 3°C, the fluid control unit 132 and the multiple fluid distribution units 133 of the liquid level adjustment structure 13 are opened, and the opening sizes of the multiple fluid distribution units 133 are adjusted so that the liquid level of the coolant in the first layer of liquid cooling space 101 from top to bottom is reduced by 15%, the liquid level of the coolant in the second layer of liquid cooling space 101 remains unchanged, and the liquid levels of the coolant in the third layer of liquid cooling space 101 and the fourth layer of liquid cooling space 101 are increased by 5% and 10%, respectively.

[0079] (3) When the maximum temperature difference between the battery cells 211 of the two battery modules 21 in the box body 11 is greater than 3°C, the fluid control unit 132 and the multiple fluid distribution units 133 of the liquid level adjustment structure 13 are opened, and the opening sizes of the multiple fluid distribution units 133 are adjusted so that the liquid level of the coolant in the first layer of liquid cooling space 101 from top to bottom is reduced by 30%, the liquid level of the coolant in the second layer of liquid cooling space 101 remains unchanged, and the liquid levels of the coolant in the third layer of liquid cooling space 101 and the fourth layer of liquid cooling space 101 are increased by 10% and 20% respectively.

[0080] (4) When the maximum temperature difference between the cells 211 of the two battery modules 21 in the housing 11 exceeds 10°C, the coolant is replenished through the replenishment pipeline 124. On the basis of the total volume of the coolant currently circulating in the housing 11, another 10% of the coolant is introduced, and the supply flow rate of the coolant at the inlet pipeline 121 is increased accordingly.

[0081] It should be noted that the above control strategy is only an example of an actual control situation. If the temperature of the battery cell 211 of the battery module 21 in the partial liquid cooling space 101 is abnormal, the liquid level height or the coolant flow rate of the immersion coolant in the liquid cooling space 101 can also be controlled separately to improve the heat dissipation capacity of the coolant in the liquid cooling space 101. For example, in order to control the coolant flow rate in each liquid cooling space 101, a flow control valve can be designed in each pipeline of the fluid circulation structure 12, that is, a flow control valve can be set in the liquid inlet pipeline 121, the series flow pipeline 122 or the liquid outlet pipeline 123. So that when it is necessary to adjust the flow rate of the coolant in part of the liquid cooling space 101 separately, precise control can be achieved.

[0082] Those skilled in the art will appreciate that the above-mentioned embodiments are specific examples for implementing the present application, and in actual applications, various changes may be made thereto in form and detail without departing from the spirit and scope of the present application.

Claims

1. An immersion liquid cooling device, characterized in that: include: A box body having a plurality of liquid cooling spaces arranged in sequence along a preset direction and isolated from each other, the box body comprising a cavity wall surrounding a closed space, and an isolating member separating the closed space into a plurality of liquid cooling spaces, each of the liquid cooling spaces being used to accommodate a battery module; a fluid circulation structure connected to the cavity wall of the box body, the fluid circulation structure comprising a liquid inlet pipeline, a series flow pipeline and a liquid outlet pipeline, the liquid inlet pipeline is used to supply coolant, the series flow pipeline is used to transmit coolant, and the liquid outlet pipeline is used to discharge coolant, one of the two liquid cooling spaces farthest apart in the preset direction is connected to the liquid inlet pipeline, and the other is connected to the liquid outlet pipeline, and two adjacent liquid cooling spaces are connected to each other via the series flow pipeline; A liquid level regulating structure is connected to the cavity wall of the box body, and the liquid level regulating structure includes a bypass pipeline connecting each of the liquid cooling spaces, and also includes a fluid control unit and a plurality of fluid distribution units arranged on the bypass pipeline. The fluid distribution unit is arranged corresponding to the liquid cooling space, and the fluid distribution unit is used to distribute cooling liquid to the liquid cooling space. The fluid control unit is used to control the amount of liquid distributed by the fluid distribution unit to the corresponding liquid cooling space to adjust the liquid level of the corresponding liquid cooling space.

2. The immersion liquid cooling device according to claim 1, characterized in that: The liquid inlet pipeline and the liquid outlet pipeline are arranged on one side or both sides of the box along a first direction, and the first direction is perpendicular to the arrangement direction of the multiple battery cells in the battery module.

3. The immersion liquid cooling device according to claim 2, characterized in that: There are multiple series flow pipelines, each of which is connected to two adjacent liquid cooling spaces in the preset direction, and multiple series flow pipelines are alternately arranged on both sides of the box along the first direction along the preset direction.

4. The immersion liquid cooling device according to claim 2, characterized in that: There are multiple liquid inlet pipelines, multiple liquid outlet pipelines, and multiple series flow pipelines connecting the two liquid cooling spaces, and the multiple liquid inlet pipelines, multiple liquid outlet pipelines, and multiple series flow pipelines connecting the two liquid cooling spaces are all arranged at intervals along the first direction.

5. The immersion liquid cooling device according to claim 1, characterized in that: The box body includes a bracket, the cavity wall is arranged on the bracket to form a closed space, the bracket is provided with a plurality of platforms corresponding to the plurality of liquid cooling spaces, each of the platforms has a hollow area, and each of the platforms is used to support the battery module and separate the battery module from the isolation member.

6. The immersion liquid cooling device according to claim 5, characterized in that: The bracket includes a plurality of pillars abutting the cavity wall, a plurality of connecting rod assemblies arranged in sequence along the preset direction and connecting the plurality of the pillars together, and an intermediate rod assembly arranged corresponding to the liquid cooling space and connected to the connecting rod assembly, each of the intermediate rod assemblies includes a plurality of intermediate rods arranged at intervals and used to support the battery module, and the extension direction of the intermediate rods is parallel to the arrangement direction of the plurality of battery cells in the battery module.

7. The immersion liquid cooling device according to claim 6, characterized in that: The bracket also includes a reinforcing rib assembly arranged corresponding to the liquid cooling space and connected to the intermediate rod assembly, each of the reinforcing rib assemblies includes a plurality of reinforcing ribs arranged at intervals, and each of the reinforcing ribs does not protrude from the intermediate rod in the preset direction.

8. The immersion liquid cooling device according to claim 1, characterized in that: The fluid circulation structure further includes a liquid replenishing pipeline, and the liquid replenishing pipeline and the liquid inlet pipeline are connected to the same liquid cooling space.

9. An energy storage system, characterized in that: include: A battery module, comprising a plurality of battery cells arranged in sequence; The immersion liquid cooling device according to any one of claims 1 to 8, wherein each liquid cooling space of the housing of the immersion liquid cooling device accommodates at least one of the battery modules.

10. A thermal management method applied to the immersion liquid cooling device according to any one of claims 1 to 8, characterized in that: include: The coolant enters each liquid cooling space of the box through the fluid circulation structure and is maintained at the initial liquid level; Detecting the temperature of the battery cells of each battery module in the liquid cooling space; If the temperature of the battery cells of the battery module in the liquid cooling space exceeds the threshold range, the coolant in the liquid cooling space is controlled by the fluid control unit to increase the liquid level under the distribution of the fluid distribution unit; if the temperature of the battery cells of the battery module in the liquid cooling space does not exceed the threshold range, the coolant in the liquid cooling space is maintained at the initial liquid level.

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