Immersed liquid cooling energy storage system

Abstract

The embodiment of the invention relates to the technical field of electric energy storage, and discloses an immersed liquid cooling energy storage system. The liquid storage tank with the multiple liquid leakage holes is arranged above the battery cluster unit, the liquid outlet pipe outside the energy storage box conveys the cooling liquid into the liquid storage tank through the cooling pipe, and the cooling liquid in the liquid storage tank flows downwards from the liquid leakage holes under the action of gravity and cools the battery cluster unit. Therefore, the cooling liquid can accurately cool the battery cluster unit, reduce dead zones in the energy storage box, cool a heating concentrated area, and enhance the temperature equalization effect. Moreover, the cooling liquid flows and is attached to the surfaces of the battery cluster units under the action of gravity, so that an energy storage box does not need to be filled with the cooling liquid in a traditional immersion type liquid cooling manner, and the use amount of the cooling liquid can be reduced.

Description

[0001] CROSS-REFERENCE TO RELATED APPLICATIONS

[0002] This application is a divisional application of the Chinese invention patent application with the application date of November 18, 2024, application number 202411657482.8, and invention name “A submerged liquid-cooled energy storage system”. Technical Field

[0003] The embodiments of the present invention relate to the field of electric energy storage technology, and in particular to an immersion liquid-cooled energy storage system. Background Art

[0004] New energy technologies like wind and solar power are developing rapidly, and the accompanying battery energy storage systems are also evolving rapidly. Currently, to improve efficiency, battery energy storage systems are trending towards higher energy densities. This can increase heat generation and the risk of thermal runaway. Therefore, there is a need for a battery energy storage system with efficient cooling performance.

[0005] Immersion cooling technology involves directly immersing energy storage units, such as battery packs or cells, in an insulating coolant. This coolant absorbs the heat generated by the unit during operation, ensuring the battery operates within its optimal temperature range. Compared to traditional air cooling, immersion cooling offers greater cooling efficiency and safety.

[0006] Existing immersion-cooled energy storage systems typically use insulating coolant to fill the energy storage cabinet, submerging the battery cells within. However, existing immersion cooling methods suffer from insufficient heat exchange and poor temperature uniformity due to dead zones within the cabinet and varying flow rates in different areas. Summary of the Invention

[0007] The purpose of the embodiments of the present invention is to provide an immersion liquid-cooled energy storage system that can reduce dead zones inside the energy storage box, cool areas where heat is concentrated, reduce the amount of coolant used, and enhance the temperature equalization effect.

[0008] To solve the above technical problems, an embodiment of the present invention provides an immersion liquid-cooled energy storage system, comprising:

[0009] An energy storage box; a battery cluster unit, arranged in the energy storage box; an infusion pipe, arranged on the outside of the energy storage box, the infusion pipe being used to transport coolant; a liquid storage tank, arranged in the energy storage box, the liquid storage tank comprising a bottom plate and multiple side plates connected to the bottom plate, the bottom plate being fixed to the top of the battery cluster unit and provided with multiple leakage holes; multiple side plates are connected end to end along the edge of the bottom plate and extend in a direction away from the battery cluster unit; a cooling pipe, arranged on a side of the liquid storage tank away from the battery cluster unit, one end of the cooling pipe being connected to the infusion pipe, and the other end being arranged opposite to the liquid storage tank, the cooling pipe being used to transport coolant to the liquid storage tank, the coolant flowing downward through the leakage holes under the action of gravity and cooling the battery cluster unit.

[0010] The immersion-type liquid-cooled energy storage system of an embodiment of the present invention features a liquid storage tank with multiple leakage holes positioned above the battery cluster units. A liquid outlet pipe on the outside of the energy storage tank delivers coolant to the tank via a cooling pipe. The coolant in the tank flows downward through the leakage holes under the action of gravity, cooling the battery cluster units. This allows the coolant to accurately cool the battery cluster units, reducing dead zones within the energy storage tank and cooling concentrated heat areas to enhance temperature uniformity. Furthermore, because the coolant flows under the action of gravity and adheres to the surface of the battery cluster units, there is no need to fill the energy storage tank with coolant, as with traditional immersion liquid cooling, thus reducing coolant usage.

[0011] Optionally, it further includes a plurality of support members arranged at intervals along the vertical direction, wherein the plurality of support members are fixed in the energy storage box, and there are a plurality of battery cluster units, which are arranged one-to-one on the support members; there are a plurality of cooling pipes, which are arranged at intervals along the vertical direction, wherein one end of the plurality of cooling pipes is connected to the infusion pipe, and the other ends of the plurality of cooling pipes are arranged one-to-one opposite to the liquid storage tank.

[0012] Optionally, the battery cluster unit includes a plurality of battery cells, and a heat dissipation gap is provided between two adjacent battery cells. The coolant in the liquid storage tank enters the heat dissipation gap through the leakage hole to cool the battery cells.

[0013] Optionally, each of the cooling tubes has a plurality of branch tubes spaced apart in a horizontal direction, each of the branch tubes has a liquid outlet, and the plurality of branch tubes transport cooling liquid to the corresponding liquid storage tank through the corresponding liquid outlets.

[0014] Optionally, the liquid outlet is configured such that an inner dimension along the horizontal direction is larger than an inner dimension along the vertical direction.

[0015] Optionally, the plurality of leakage holes are arranged in an array, and some of the leakage holes are arranged along the extension direction of the heat dissipation gap and face the heat dissipation gap.

[0016] Optionally, the leakage hole facing the heat dissipation gap is arranged facing the liquid outlet.

[0017] Optionally, a drainage portion is provided on the edge of the leakage hole facing the heat dissipation gap on the side away from the side plate, one end of the drainage portion is connected to the edge of the leakage hole, and the other end is connected to the side wall of the battery cell, and the drainage portion is used to drain the coolant flowing out of the leakage hole to the side wall of the battery cell.

[0018] Optionally, an edge of the leakage hole facing the heat dissipation gap in the arrangement direction of the battery cells does not exceed an edge of a side wall of the battery cells.

[0019] Optionally, at least one of the side panels is provided with at least one overflow port. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] One or more embodiments are exemplarily illustrated by pictures in the corresponding drawings. These exemplifications do not constitute limitations on the embodiments. Elements with the same reference numerals in the drawings are represented as similar elements. Unless otherwise stated, the figures in the drawings do not constitute proportional limitations.

[0021] Figure 1 is a structural schematic diagram of an immersion liquid-cooled energy storage system according to a first embodiment of the present invention;

[0022] Figure 2 2. It is a schematic structural diagram of a layer battery cluster of an immersion liquid-cooled energy storage system according to a first embodiment of the present invention;

[0023] Figure 3 2 is a schematic structural diagram of a liquid storage tank of an immersion liquid-cooled energy storage system according to a first embodiment of the present invention;

[0024] Figure 4 yes Figure 2 Schematic top view of the layer battery cluster;

[0025] Figure 5 1. It is a schematic structural diagram of cooling pipes and branch pipes of an immersion liquid-cooled energy storage system according to a first embodiment of the present invention;

[0026] Figure 6 yes Figure 5 A bottom view schematic diagram of the cooling pipe and branch pipe;

[0027] Figure 7 yes Figure 4 Schematic cross-sectional view of the layer battery cluster along line AA';

[0028] Figure 8 2 is a schematic structural diagram of a housing of an immersion liquid-cooled energy storage system according to a second embodiment of the present invention;

[0029] Figure 9 yes Figure 8 A schematic top view of a housing;

[0030] Figure 10 2. It is a schematic exploded view of the structure of the housing and layer battery cluster of the immersion liquid-cooled energy storage system according to the second embodiment of the present invention;

[0031] Figure 11 This is a schematic structural diagram of another housing of an immersion liquid-cooled energy storage system according to a second embodiment of the present invention;

[0032] Figure 12 yes Figure 11 Schematic diagram of the top view of the shell. DETAILED DESCRIPTION

[0033] To make the objectives, technical solutions, and advantages of the embodiments of the present invention more apparent, various embodiments of the present invention will be described in detail below with reference to the accompanying drawings. However, those skilled in the art will appreciate that many technical details are provided in various embodiments of the present invention to help readers better understand the present invention. However, even without these technical details and various variations and modifications based on the following embodiments, the technical solutions claimed in the present invention can still be implemented.

[0034] In the embodiments of the present invention, terms such as "upper," "lower," "left," "right," "front," "back," "top," "bottom," "inner," "outer," "center," "vertical," "horizontal," "transverse," and "longitudinal" to indicate directions or positions are based on the directions or positions shown in the accompanying drawings. These terms are primarily intended to better describe the present invention and its embodiments and are not intended to limit the devices, elements, or components indicated to having a specific direction, or to being constructed or operated in a specific direction.

[0035] Furthermore, some of the above terms may be used to express other meanings besides indicating a position or location. For example, the term "on" may also be used to indicate a dependency or connection in certain circumstances. Those skilled in the art will understand the specific meanings of these terms in the present invention based on the specific circumstances.

[0036] Furthermore, the terms "installed," "set," "provided with," "opened," "connected," and "connected" should be interpreted broadly. For example, they can refer to fixed connections, removable connections, or integral structures; mechanical connections or electrical connections; direct connections or indirect connections through an intermediary; or internal communication between two devices, elements, or components. Those skilled in the art will understand the specific meanings of these terms in the present invention based on specific circumstances.

[0037] Furthermore, the terms "first," "second," etc., are primarily used to distinguish between different devices, elements, or components (which may or may not be of the same type and configuration), and are not intended to indicate or imply the relative importance or quantity of the devices, elements, or components indicated. Unless otherwise specified, "plurality" means two or more.

[0038] In practice, existing immersion-cooled energy storage systems experience temperature stratification within the tank, with the upper layer being hotter and the lower layer being colder, due to the lower density of the heated liquid. Coolant flow rates vary at different locations, and the heat exchange rate between the battery cells and the coolant is uneven. These deficiencies lead to dead zones within the tank, as well as insufficient heat exchange caused by varying flow rates in different areas, resulting in poor temperature uniformity.

[0039] In one embodiment of the present invention, an immersion-type liquid-cooled energy storage system features a liquid storage tank with multiple leakage holes positioned above the battery cluster units. A liquid outlet pipe on the outside of the energy storage tank delivers coolant to the tank via a cooling pipe. Under the influence of gravity, the coolant in the tank flows downward through the leakage holes, cooling the battery cluster units. This allows the coolant to accurately cool the battery cluster units, reducing dead zones within the energy storage tank and cooling concentrated heat areas to enhance temperature uniformity. Furthermore, because the coolant flows under the influence of gravity and adheres to the surface of the battery cluster units, there is no need to fill the energy storage tank with coolant, as with traditional immersion liquid cooling, thus reducing coolant usage.

[0040] It should be noted that the "immersion liquid-cooled energy storage system" referred to in this embodiment can be either an industrial and commercial energy storage system (referred to as "IC storage") or a large-scale energy storage system (referred to as "large storage"). IC storage typically serves industrial and commercial users and is relatively small in scale, with capacities generally ranging from a few kilowatts to several megawatts. Large-scale storage, on the other hand, serves a wider range of power grids and energy markets and is larger in scale, with capacities typically in the tens of megawatts or even greater.

[0041] The following is a detailed description of the implementation details of the immersion liquid-cooled energy storage system of the first embodiment of the present invention. The following content is only provided for easy understanding of the implementation details and is not necessary for the implementation of this solution.

[0042] See also Figures 1 to 3 The submerged energy storage system 100 of this embodiment includes: an energy storage box 110, a battery cluster unit 120 disposed in the energy storage box 110, a liquid infusion pipe 130 disposed outside the energy storage box 110, the liquid infusion pipe 130 being used to transport coolant, a liquid storage tank 140 disposed in the energy storage box 110, and a cooling pipe 150 disposed on a side of the liquid storage tank 140 facing away from the battery cluster unit 120.

[0043] The liquid reservoir 140 includes a bottom plate 141 and multiple side plates 142 connected to the bottom plate 141. The bottom plate 141 is fixed to the top of the battery cluster unit 120 and is provided with multiple leakage holes 141a. The multiple side plates 142 are connected end to end along the edge of the bottom plate 141 and extend away from the battery cluster unit 120.

[0044] One end of the cooling pipe 150 is connected to the liquid delivery pipe 130 , and the other end is arranged opposite to the liquid storage tank 140 . The cooling pipe 150 is used to deliver coolant to the liquid storage tank 140 . The coolant flows downward through the leakage hole 141 a under the action of gravity and cools the battery cluster unit 120 .

[0045] During operation of the battery cluster unit 120, the coolant is delivered by the liquid delivery tube 130 to the cooling tube 150. The coolant then flows through the cooling tube 150 into the liquid reservoir 140, where it is dispersed through the leakage holes 141a in the liquid reservoir 140. The coolant then flows downward under the action of gravity, cooling the battery cluster unit 120. This allows the coolant to precisely cool the battery cluster unit 120, reducing dead zones within the energy storage box 110 and cooling concentrated heat areas, thereby enhancing temperature uniformity and reducing coolant usage.

[0046] It will be appreciated that the coolant can flow from the leakage hole 141a in the form of drops or a continuous "stream." When dripping, the dripping rate can be controlled by controlling the flow rate per unit time of the cooling tube 150. Furthermore, due to the configuration of this embodiment, the coolant can cover the surface of the battery cluster unit 120, which can also be considered as immersion liquid cooling for the battery cluster unit 120.

[0047] At least one side panel 142 of the liquid storage tank 140 may be provided with at least one overflow port 142a. This overflow port 142a prevents coolant accumulation in the liquid storage tank 140. In this embodiment, the overflow port 142a also serves as a wiring harness outlet for the battery cluster unit 120, thereby simplifying the overall structure of the immersion-cooled energy storage system 100.

[0048] The overflow port 142a can be a notch provided at the top edge of the side plate 142, or a through hole provided in the middle or lower part of the side plate 142. In some embodiments, the overflow port 142a can be set in the vertical direction, and its diameter gradually decreases from top to bottom. For example, it can be set to an inverted triangle, an inverted trapezoid, a semicircle, a semi-ellipse or other similar shapes. In this way, when the coolant accumulation in the liquid storage tank 140 is more serious, the liquid level is higher, and the diameter of the overflow port 142a is larger, so the coolant can be discharged faster to alleviate the coolant accumulation. When the coolant accumulation is alleviated, the liquid level is lowered, and the position corresponding to the smaller diameter of the overflow port 142a can reduce the flow rate of the coolant outflowing from the overflow port 142a. While alleviating the coolant accumulation, it ensures that more coolant can flow downward from the leakage hole 141a to cool the battery cluster unit 120, so that the coolant has a higher utilization rate.

[0049] The edge of the side panel 142 that encloses the overflow vent 142a can be provided with a flow-guiding structure. This can prevent the coolant flow from being blocked by the edge of the overflow vent 142a due to machining errors during the product manufacturing process. For example, a chamfer can be provided at the edge of the side panel 142 that encloses the overflow vent 142a, so that the thickness of the side panel 142 in this area gradually decreases from the inner edge of the side panel 142 toward the outer edge of the side panel 142. Optionally, the chamfer can be an oblique chamfer or a rounded chamfer.

[0050] The immersion liquid-cooled energy storage system 100 also includes a liquid outlet pipe (not shown) disposed at the bottom of the energy storage tank 110. One end of the liquid outlet pipe is connected to the energy storage tank 110 and communicates with the interior of the energy storage tank 110, while the other end is located outside the energy storage tank 110. The liquid outlet pipe is used to discharge coolant accumulated inside the energy storage tank 110, thereby achieving coolant circulation.

[0051] Outside the energy storage tank 110, the immersion liquid-cooled energy storage system 100 may be equipped with a circulation device (not shown), such as a pump, and a cooling device, such as a condensing device. The pump provides power to drive the coolant out of the outlet pipe and re-enter the energy storage tank 110 for cooling. It is understood that before the coolant re-enters the energy storage tank 110 for cooling, it is cooled by the cooling device so that the coolant can efficiently cool the battery cluster units 120.

[0052] It should be noted that energy storage tank 110 is the submerged housing of immersion-cooled energy storage system 100, used to house the battery cluster and coolant. Immersion-cooled energy storage system 100 also has a packaging housing (not shown) for housing energy storage tank 110, the aforementioned circulation device, and the cooling device. Furthermore, the circuitry within immersion-cooled energy storage system 100, including control devices such as the power control board and inverter, is also housed within the packaging housing.

[0053] A valve can be installed at the outlet pipe. By controlling the flow rate of the valve and the flow rate of the liquid infusion pipe 130, the circulation speed of the coolant can be controlled. In addition, if thermal runaway of the battery occurs within the immersion-type liquid-cooled energy storage system 100, the valve flow rate can be reduced or closed, while the flow rate of the liquid infusion pipe 130 can be increased to completely fill the internal space of the energy storage tank 110 with coolant, achieving full immersion and effectively controlling thermal runaway.

[0054] See again Figure 1 The immersion liquid-cooled energy storage system 100 further includes a support member 160 fixed in the energy storage box 110. There is at least one support member 160, which divides the internal space of the energy storage box 110 into at least two spaces distributed in the vertical direction for accommodating the battery cluster units 120.

[0055] In some embodiments, there are multiple support members 160, which are spaced apart in the vertical direction, dividing the internal space of the energy storage box 110 into multiple vertically distributed spaces for accommodating the battery cluster units 120. Accordingly, a corresponding liquid storage tank 140 is provided on the top of each battery cluster unit 120. In this case, there are also multiple cooling pipes 150, which are spaced apart in the vertical direction. Each cooling pipe 150 has one end connected to the infusion pipe 130, and the other end of each cooling pipe 150 is arranged above the corresponding liquid storage tank 140 for supplying coolant to the corresponding liquid storage tank 140. The support members 160 are used to support the battery cluster units 120. It is understood that the support members 160 can be support plates, brackets, etc., and the multiple support members 160 can be an integrated structure or independent structures.

[0056] When support member 160 is a support plate, it can be configured as a liquid cooling plate. The plate has internally provided liquid cooling channels for delivering coolant. The liquid cooling plate is provided with a liquid inlet and a first liquid outlet. The liquid inlet can be connected to cooling pipe 150, while the first liquid outlet can remain open or connected to a pipeline that delivers coolant flowing from the liquid cooling plate to the bottom of energy storage tank 110. In this way, support member 160, acting as a liquid cooling plate, can cool the bottom of battery cluster unit 120, further improving the cooling effect on battery cluster unit 120 and the overall temperature uniformity of the energy storage system.

[0057] When a liquid cooling channel is provided inside the support member 160, the liquid cooling channel can be provided as a serpentine channel to improve the cooling effect. In addition, to facilitate connection between the first liquid outlet and the cooling pipe 150, the first liquid outlet can be provided on a side of the support member 160 close to the cooling pipe 150.

[0058] When the support member 160 is a bracket, such as a grid-shaped bracket, it is convenient for the coolant flowing out of the liquid storage tank 140 to flow downward, which is beneficial to the circulation of the coolant.

[0059] In some other embodiments, a single support member 160 may have multiple battery cluster units 120 arranged horizontally, forming a layered battery cluster. Each battery cluster unit 120 has a corresponding liquid reservoir 140, and each liquid reservoir 140 also has a corresponding cooling tube 150. In this case, the liquid delivery tube 130 may be vertically connected to multiple liquid distribution tubes (not shown), each of which is connected to multiple cooling tubes 150 corresponding to the multiple battery cluster units 120 arranged on a single support member 160.

[0060] Or, see Figures 2 to 4 Each cooling tube 150 can be connected to multiple branch tubes 151, which are arranged horizontally, for example, along the arrangement of the battery cluster units 120. Each branch tube 151 has a second liquid outlet 151a. The multiple branch tubes 151 on a cooling tube 150 are used to deliver coolant to the corresponding liquid reservoir 140. This allows coolant to be delivered to different liquid reservoirs 140 simultaneously, with the coolant flowing downward through the multiple leakage holes 141a to cool the battery cells 121, improving cooling efficiency.

[0061] join Figure 5 and Figure 6 In some embodiments, the second liquid outlet 151a is configured such that its horizontal inner dimension is larger than its vertical inner dimension. Alternatively, the branch pipe 151 can be configured such that its horizontal dimension is larger than its vertical dimension. In other words, by configuring the branch pipe 151 in a flat shape, the vertical dimension of the branch pipe 151 can be reduced, thereby reducing the height of the immersion liquid-cooled energy storage system 100. Furthermore, the cooling pipe 150 can also be configured in a flat shape.

[0062] Correspondingly, the second liquid outlet 151a can be set to a triangle, a prism, a rectangle, a waisted circle, an ellipse, a wavy line, etc., which can not only reduce the volume occupied by the flow channel in the vertical direction, but also increase the contact area between the coolant flowing out of the second liquid outlet 151a and the bottom plate 141, further accelerating the speed at which the coolant spreads across the bottom plate 141 and improving the cooling efficiency.

[0063] The portion of the side plate 142 near the second liquid outlet 151a can be bent or tilted toward the interior of the liquid reservoir 140; alternatively, a plate-like structure extending toward the second liquid outlet 151a can be provided at the top of the portion of the side plate 142 near the second liquid outlet 151a; alternatively, the distance between the second liquid outlet 151a and the bottom plate 141 can be reduced to reduce or avoid impact between the coolant and the bottom plate 141. This configuration can prevent splashing of the coolant when it flows out of the second liquid outlet 151a.

[0064] It is understood that the size of the second liquid outlet 151a can be set to different sizes according to the actual size of the immersion liquid-cooled energy storage system 100, which can also reduce or avoid coolant splashing. For example, the diameter of the liquid outlet 151a can be set to 10mm-50mm.

[0065] Due to the large size of commercial or large-scale energy storage, existing liquid cooling channel designs cannot guarantee consistent cooling efficiency across different areas within the energy storage system. For example, there are areas within the energy storage system that cannot be reached or immersed by the coolant, or the coolant flow rates in different areas of the energy storage system vary, resulting in significant differences in heat exchange efficiency. Some areas have low heat exchange efficiency. Areas that cannot be immersed by the coolant and areas with low heat exchange efficiency are generally referred to as dead zones. The gaps between adjacent batteries in an energy storage system are typical locations for dead zones. Therefore, ensuring that the coolant immerses the gaps between batteries and improving the coolant flow efficiency in the gaps between batteries is an important means of reducing dead zones.

[0066] See also Figure 7 The battery cluster unit 120 generally includes a plurality of battery cells 121, with a heat dissipation gap 122 between two adjacent battery cells 121. Specifically, the coolant flowing out of the leakage hole 141a of the liquid reservoir 140 enters the heat dissipation gap 122 and contacts the sidewalls of the battery cells 121 to achieve heat exchange.

[0067] Corresponding to the multiple heat dissipation gaps 122 formed by the multiple battery cells 121, at least part of the multiple leakage holes 141a arranged in an array are arranged along the extension direction of the heat dissipation gap 122 and are directly opposite to the heat dissipation gap 122. Specifically, each heat dissipation gap 122 extends along a straight line, and there are multiple leakage holes 141a directly opposite to the heat dissipation gap 122, and are arranged along the extension direction of the heat dissipation gap 122. Moreover, each heat dissipation gap 122 has multiple leakage holes 141a corresponding to it. Such an arrangement allows the coolant to accurately enter the heat dissipation gap 122 between adjacent battery cells 121. At the same time, the coolant at different positions flows downward under the action of gravity, and the fluidity tends to be consistent, which can reduce the cooling dead zone of the immersion liquid-cooled energy storage system 100 and improve the overall temperature uniformity effect.

[0068] See again Figure 4 and Figure 7In some embodiments, the leakage holes 141a can also be staggered. Specifically, considering the series connection requirements of multiple adjacent battery cells 121, the electrodes of adjacent battery cells 121 need to be electrically connected through the staggered metal sheets 124. Since the metal sheets 124 need to occupy part of the space of the bottom plate 141, the leakage holes 141a are set at the positions of the bottom plate 141 where the metal sheets 124 are not set, while the leakage holes 141a may not be set in the areas where the metal sheets 124 are set. Therefore, the leakage holes 141a are staggered as a whole. At this time, one heat dissipation gap 122 may correspond to one larger leakage hole 141a, or to multiple smaller leakage holes 141a.

[0069] In some other embodiments, the middle portion of the metal sheet 124 of two adjacent battery cells 121 connected in series may be bent and convex in a direction away from the battery cells 121, leaving space below this portion of the metal sheet 124. Linear leakage holes 141a may be provided in the area of ​​the bottom plate 141 of this portion of the metal sheet 124, so that the coolant can pass through these linear leakage holes 141a into the heat dissipation gap 122 between the corresponding adjacent battery cells 121.

[0070] Optionally, the specific shape of the leakage hole 141a can be a circular hole, an elliptical hole, a straight hole, a waisted circular hole, a curved hole, a broken line hole or a through hole of other shapes. When the leakage hole 141a is in the shape of a linear hole, its extension direction is roughly the same as the extension direction of the heat dissipation gap 122. In this way, the contact area between the coolant flowing out of the leakage hole 141a and the side wall of the battery cell 121 can be increased, thereby improving the cooling efficiency. It can be understood that circular through holes generally have higher flow efficiency than square through holes, and when the diameter of the circular hole is the same as the short axis of the elliptical hole and the diameter of the semicircular part of the waisted circular hole, since the elliptical hole and the waisted circular hole have a larger area, their flow rate is also greater. When the leakage hole 141a is set as a square hole, the flow efficiency of the coolant passing through the leakage hole 141a can be improved by setting the hole as a square hole with rounded corners, and / or setting the edge of the hole as a chamfer.

[0071] In some other embodiments, the length of the branch tube 151 can be extended, and multiple second liquid outlets 151a can be arranged at intervals on the branch tube 151, so that the branch tube 151 can simultaneously transport coolant to different positions of the liquid storage tank 140, so that the coolant can quickly fill the liquid storage tank 140, thereby improving the cooling efficiency.

[0072] The leakage hole 141a facing the heat dissipation gap 122 is arranged opposite the second liquid outlet 151a. With this arrangement, the coolant flowing out of the second liquid outlet 151a can flow directly to the location of the corresponding leakage hole 141a, and then enter the heat dissipation gap 122 through the leakage hole 141a at that location, achieving accurate and rapid heat dissipation.

[0073] In some embodiments, a drainage portion (not shown) is provided on the edge of the leakage hole 141a facing the heat dissipation gap 122 on the side facing away from the side plate 142. One end of the drainage portion is connected to the edge of the leakage hole 141a, and the other end is connected to the side wall of the battery cell 121. The drainage portion is used to drain the coolant flowing out of the leakage hole 141a to the side wall of the battery cell 121. For example, an inclined wall can be provided on a side of the bottom plate 141 facing away from the side plate 142 and corresponding to the edge of the leakage hole 141a. One end of the inclined wall is connected to the edge of the leakage hole 141a, and the other end is in contact with the side wall of the battery cell 121. When the coolant flows out of the leakage hole 141a, the coolant is affected by the inclined wall and flows along the inclined wall, and then flows from the inclined wall to the side wall of the battery cell 121.

[0074] Optionally, the position where the inclined wall meets the edge of the leakage hole 141 a can be set as an inclined chamfer or a rounded chamfer, which can better achieve the drainage effect and drain the coolant to the side wall of the battery cell 121.

[0075] In other embodiments, the edge of the leakage hole 141a, which faces the heat dissipation gap 122, in the arrangement direction of the battery cells 121, does not extend beyond the edge of the sidewall of the battery cells 121. For example, the edge of the leakage hole 141a may coincide with the edge of the sidewall of the battery cells 121, so that the coolant flowing out of the leakage hole 141a can flow directly onto the sidewall of the battery cells 121. Alternatively, the edge of the leakage hole 141a may partially expose the edge of the sidewall of the battery cells 121, so that the coolant can also flow directly onto the sidewall of the battery cells 121.

[0076] It is understandable that the position of the bottom plate 141 of each battery cell 121 that is opposite to the two side walls parallel to the arrangement direction of the multiple battery cells 121 can also be provided with the above-mentioned leakage hole 141a. In this way, the four side walls of the battery cell 121 that are perpendicular to the bottom plate 141 can all be cooled by the coolant.

[0077] The bottom plate 141 may be provided with a diversion structure in the area near the leakage hole 141a. This prevents errors during the product manufacturing process from causing the bottom plate 141 near the leakage hole 141a to block the coolant from flowing downward through the leakage hole 141a. For example, the thickness of the bottom plate 141 near the leakage hole 141a may be gradually reduced. Specifically, the edge of the leakage hole 141a may be provided with an oblique chamfer or a rounded chamfer. Alternatively, a diversion groove connected to the leakage hole 141a may be provided in the area near the leakage hole 141a. After entering the diversion groove, the coolant can flow through the diversion groove to the leakage hole 141a.

[0078] The base plate 141 may be provided with multiple positioning grooves (not shown). The contours of the positioning grooves match the contours of the electrodes of the battery cells 121. The positioning grooves are used to align and position the electrodes of the battery cells 121. When assembling the battery cluster unit 120, the electrodes of the battery cells 121 can be aligned with the positioning grooves and inserted into the positioning grooves. This facilitates faster assembly of the battery cluster unit 120 and maintains consistency in the heat dissipation gaps 122.

[0079] See again Figure 3 and Figure 4 Furthermore, the bottom plate 141 may be provided with a plurality of pressure relief holes 141b, which are used to expose the explosion-proof valve 121a on the top of the battery cell 121. In this way, the safety performance of the immersion liquid-cooled energy storage system 100 can be guaranteed.

[0080] In this embodiment, the liquid reservoir 140 can be made of transparent structural plastic, and then cured by UV (Ultraviolet) to bond and fix the multiple battery cells 121 to the liquid reservoir 140 to form a whole. In this way, the liquid reservoir 140 can also fix the multiple battery cells.

[0081] In some embodiments, a liquid collection tank (not shown) can be provided below each battery cluster unit 120. The battery cluster unit 120 is placed in the liquid collection tank, and the depth of the liquid collection tank is less than the height of the battery cells 121. This allows the liquid collection tank to temporarily collect the coolant as it flows downward through the heat dissipation gap 122, providing immersion cooling for the bottom surface of the battery cells 121. When the coolant is high, it can overflow from the liquid collection tank and flow to the bottom of the energy storage tank 110.

[0082] The second embodiment of the submerged liquid-cooled energy storage system is substantially similar to the first embodiment, differing primarily in that the multiple battery cluster units 120 supported by the support member 160 are mounted within a housing 210. Specifically, the battery clusters are mounted within the housing 210 and can be considered to form a battery pack. In this case, a liquid collection tank is not required beneath the battery cluster units 120.

[0083] See also Figures 8 to 10 The housing 210 includes a second bottom plate 211 and a top plate 212, which are arranged opposite each other, and a plurality of second side plates 213, which are connected end-to-end to form a cylindrical side wall. The second bottom plate 211 and the top plate 212 are respectively connected to the edges of the cylindrical side wall formed by the plurality of second side plates 213. This arrangement allows the coolant delivered by the cooling pipes 150 to fill the entire interior space of the housing 210 when necessary, achieving full immersion cooling of the multiple battery cluster units 120. This not only improves cooling efficiency but also prevents the spread of thermal runaway in the event that some battery cluster units 120 experience thermal runaway.

[0084] See also Figure 8 and Figure 9 In some embodiments, the second bottom plate 211 supporting the multiple battery cluster units 120 can be configured as a liquid cooling plate, having cooling channels disposed therein for the flow of coolant. The portion of the second bottom plate 211 protruding from the second side plate 213 can be provided with a liquid inlet 211a and a third liquid outlet 211b to facilitate circulation of the coolant within the second bottom plate 211. Configuring the second bottom plate 211 as a liquid cooling plate can cool the bottom of the battery cluster units 120. It is understood that the cooling channels within the second bottom plate 211 can be configured as serpentine channels to enhance cooling efficiency.

[0085] See also Figure 9 、 Figure 11 and Figure 12 It is understood that, since the overall flow direction of the coolant is from top to bottom, a fourth liquid outlet 213a can be provided at a lower position of the second side plate 213. The fourth liquid outlet 213a can discharge the coolant inside the housing 210, thereby achieving coolant circulation. Alternatively, the fourth liquid outlet 213a can also be provided on the second bottom plate 211. Compared to providing the fourth liquid outlet 213a on the lower side of the second side plate 213, providing the fourth liquid outlet 213a on the second bottom plate 211 has a lower horizontal height, which is more conducive to discharging the coolant accumulated in the housing 210, thereby achieving circulation.

[0086] See again Figure 10 In this embodiment, a cover plate 220 can be installed on the side of the liquid storage tank 140 facing away from the battery cluster unit 120. This cover plate 220 can restrict the location of the battery cluster unit 120's wiring harness, ensuring more regular wiring within the immersion liquid-cooled energy storage system. Furthermore, the cover plate 220 can be marked with the positive and negative terminals of the battery cluster unit 120, making it easier for operators to accurately connect the system's internal circuits during assembly.

[0087] The above is a detailed introduction to the immersion liquid-cooled energy storage system provided by the embodiment of the present invention. Specific examples are used herein to illustrate the principles and implementation methods of the present invention. The description of the above implementation methods is only used to help understand the ideas of the present invention. There may be changes in the specific implementation methods and application scope. In summary, the contents of this specification should not be understood as limiting the present invention.

Claims

1. An immersion liquid-cooled energy storage system, characterized in that: include: Energy storage tank; A battery cluster unit is provided in the energy storage box; A liquid infusion pipe is provided on the outside of the energy storage box and is used to transport the coolant; A liquid storage tank is provided in the energy storage box, the liquid storage tank comprising a bottom plate and a plurality of side plates connected to the bottom plate, the bottom plate being fixed to the top of the battery cluster unit and having a plurality of leakage holes; the plurality of side plates are sequentially connected end to end along the edge of the bottom plate and extend in a direction away from the battery cluster unit; a cooling pipe, disposed on a side of the liquid reservoir facing away from the battery cluster unit, one end of the cooling pipe being connected to the liquid delivery pipe and the other end being disposed opposite the liquid reservoir, the cooling pipe being used to deliver coolant to the liquid reservoir, the coolant flowing downward through the leakage hole under the action of gravity to cover the surface of the battery cluster unit and cool the battery cluster unit; The immersion liquid-cooled energy storage system further includes a liquid outlet pipe provided at the bottom of the energy storage box, one end of the liquid outlet pipe being connected to the energy storage box and communicating with the interior space of the energy storage box, and the other end being located outside the energy storage box; a valve is provided at the liquid outlet pipe, and the circulation speed of the coolant is controlled by controlling the flow rate of the valve and the flow rate of the liquid infusion pipe; If thermal runaway of the battery occurs inside the immersion liquid-cooled energy storage system, the valve flow rate is reduced or closed, and the flow rate of the liquid infusion tube is increased at the same time, so that the internal space of the energy storage tank is completely filled with coolant.

2. The immersion liquid-cooled energy storage system according to claim 1, characterized in that: It also includes a plurality of support members spaced apart in the vertical direction, wherein the plurality of support members are fixed in the energy storage box, and the plurality of battery cluster units are arranged in a one-to-one correspondence on the support members; There are multiple cooling tubes, which are spaced apart in the vertical direction. One end of each cooling tube is connected to the liquid infusion tube, and the other ends of each cooling tube are arranged opposite to the liquid storage tank in a one-to-one correspondence.

3. The immersion liquid-cooled energy storage system according to claim 1, characterized in that: The battery cluster unit includes a plurality of battery cells, and a heat dissipation gap is provided between two adjacent battery cells. The coolant in the liquid storage tank enters the heat dissipation gap through the leakage hole to cool the battery cells.

4. The immersion liquid-cooled energy storage system according to claim 3, characterized in that: Each of the cooling tubes has a plurality of branch tubes spaced apart in a horizontal direction, each of the branch tubes has a liquid outlet, and the plurality of branch tubes transport cooling liquid to the corresponding liquid storage tank through the corresponding liquid outlets.

5. The immersion liquid-cooled energy storage system according to claim 4, characterized in that: The liquid outlet is configured such that an inner dimension along the horizontal direction is larger than an inner dimension along the vertical direction.

6. The immersion liquid-cooled energy storage system according to claim 4, characterized in that: The plurality of leakage holes are arranged in an array, and some of the leakage holes are arranged along the extension direction of the heat dissipation gap and face the heat dissipation gap.

7. The immersion liquid-cooled energy storage system according to claim 6, characterized in that: The liquid leakage hole facing the heat dissipation gap is arranged facing the liquid outlet.

8. The immersion liquid-cooled energy storage system according to claim 6, characterized in that: A drainage portion is provided on the edge of the leakage hole facing the heat dissipation gap on the side away from the side plate, one end of the drainage portion is connected to the edge of the leakage hole, and the other end is connected to the side wall of the battery cell. The drainage portion is used to drain the coolant flowing out of the leakage hole to the side wall of the battery cell.

9. The immersion liquid-cooled energy storage system according to claim 6, characterized in that: The edge of the leakage hole facing the heat dissipation gap in the arrangement direction of the battery cells does not exceed the edge of the side wall of the battery cells.

10. The immersion liquid-cooled energy storage system according to any one of claims 1 to 9, characterized in that: At least one of the side panels is provided with at least one overflow opening.

11. The immersion liquid-cooled energy storage system according to claim 10, characterized in that: The overflow port also serves as a harness outlet for the battery cluster unit.

12. The immersion liquid-cooled energy storage system according to any one of claims 1 to 9, characterized in that: The liquid storage tank is bonded and fixed to the plurality of battery cells.

13. The immersion liquid-cooled energy storage system according to any one of claims 1 to 9, characterized in that: The bottom plate is provided with a plurality of positioning grooves, the contours of the positioning grooves match the contours of the electrodes of the battery core, and the positioning grooves are used to cooperate with and position the electrodes of the battery core.

14. The immersion liquid-cooled energy storage system according to any one of claims 1 to 9, characterized in that: The bottom plate is provided with a plurality of pressure relief holes, and the pressure relief holes are used to expose the explosion-proof valve on the top of the battery cell.

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