Immersed liquid-cooled battery pack

Abstract

The embodiment of the invention provides an immersed liquid-cooled battery pack, which comprises a battery box shell, the battery box shell comprises a liquid-cooled bottom plate, a top plate, a side plate and a partition plate, a closed space is defined by the liquid-cooled bottom plate and the top plate, and the partition plate divides the closed space into a medium oil area and a functional dry area, the medium oil area is used for filling an immersion medium; the battery module is positioned in the medium oil area and is arranged on the liquid cooling bottom plate; the cooling pipe assembly is arranged on the side, away from the liquid cooling bottom plate, of the battery module, and the cooling pipe assembly and the liquid cooling bottom plate are both used for being filled with a cooling medium. And the immersion medium is sealed in the battery pack and is static, so that the leakage problem caused by the flowing of the immersion medium in a pipeline and the problems of local flowing dead zone, turbulence and inconsistent liquid pressure caused by the flowing of the medium are avoided, the heat dissipation area is increased, and the heat exchange capability of the battery is enhanced.

Description

Technical Field

[0001] The embodiments of the present invention relate to the technical field of liquid-cooled batteries, and in particular to an immersion liquid-cooled battery pack. Background Art

[0002] Lithium-ion battery energy storage, a major emerging energy storage technology, has seen rapid growth in installed capacity in recent years. To improve the cycle performance and number of lithium-ion batteries and avoid issues such as thermal runaway that could impact energy storage system safety, lithium-ion batteries must be kept within a reasonable temperature range during use. For lithium iron phosphate batteries, the operating temperature should be between 25°C and 45°C. All lithium-ion battery energy storage systems require thermal management devices.

[0003] Currently, the main thermal management solutions for lithium-ion batteries are air cooling and liquid cooling. The main issues with air cooling are large temperature variations between different batteries and high air conditioning energy consumption. Liquid cooling can reduce air conditioning energy consumption, but current liquid cooling solutions generally use a liquid cooling baseplate. The lithium-ion batteries are placed on top of the liquid cooling baseplate. Heat generated during battery charging and discharging is transferred from top to bottom to the liquid cooling baseplate. This results in a long vertical heat transfer path, a low heat transfer coefficient, and a large temperature gradient between the top and bottom of the battery.

[0004] As the capacity of energy storage cells increases and integration density continues to rise, immersion thermal management technology based on direct liquid cooling is gaining significant application value. Currently, many designs utilize dynamic immersion, where the immersion medium circulates within the battery pack or cluster under external driving force. This dynamic immersion approach presents the following challenges:

[0005] 1. A large number of pipelines for oily immersion media are required, which consumes a large amount of immersion media, is costly, and requires a large floor space. 2. Pipeline joints are prone to leakage, reducing system operational reliability. 3. Flow "dead zones" or localized turbulence are easily formed within the battery pack / cluster. 4. Dynamic flow pipelines connect the energy storage units in series, and leakage or contamination of a single pack can cause the entire cabin to shut down. Summary of the Invention

[0006] The embodiments of the present invention aim to solve at least one of the technical problems existing in the prior art and provide an immersion liquid-cooled battery pack.

[0007] An embodiment of the present invention provides an immersion liquid-cooled battery pack, comprising:

[0008] A battery box housing, the battery box housing comprising a liquid-cooled bottom plate, a top plate, a side plate forming a closed space with the liquid-cooled bottom plate and the top plate, and a partition plate dividing the closed space into a dielectric oil area and a functional dry area, the dielectric oil area being used to be filled with an immersion medium;

[0009] a battery module, the battery module being located in the dielectric oil area and disposed on the liquid-cooled base plate;

[0010] A cooling pipe assembly is provided on a side of the battery module away from the liquid-cooling base plate, and both the cooling pipe assembly and the liquid-cooling base plate are used to be filled with a cooling medium.

[0011] In some possible embodiments, the cooling pipe assembly includes a cooling pipe, a cooling liquid inlet, and a cooling liquid outlet;

[0012] The coolant inlet and the coolant outlet are both provided on the side panels corresponding to the functional dry areas;

[0013] The cooling pipe is arranged on a side of the battery module away from the liquid cooling base plate, the liquid inlet of the cooling pipe is communicated with the coolant inlet, and the liquid outlet of the cooling pipe is communicated with the coolant outlet.

[0014] In some possible embodiments, the cooling pipe includes a first cooling sub-pipe, a second cooling sub-pipe spaced apart from the first cooling sub-pipe, and an arc-shaped cooling sub-pipe respectively connected to the first cooling sub-pipe and the second cooling sub-pipe;

[0015] The inlet of the first cooling sub-tube is communicated with the coolant inlet, and the outlet of the second cooling sub-tube is communicated with the coolant outlet.

[0016] In some possible embodiments, the cooling pipe is a serpentine cooling pipe.

[0017] In some possible embodiments, it further includes an oil filling and draining port;

[0018] The oil filling and draining ports are arranged on the side plate corresponding to the functional dry area, and the oil filling and draining ports are communicated with the medium oil area.

[0019] In some possible embodiments, a pressure relief hole is further included;

[0020] The pressure relief hole is provided on the side plate corresponding to the functional dry area, and the pressure relief hole is communicated with the medium oil area.

[0021] In some possible embodiments, an oil indicator port is further included;

[0022] The oil indicating port is arranged on the side plate corresponding to the functional dry area, and the height of the oil indicating port is flush with the preset immersion liquid level of the medium oil area.

[0023] In some possible embodiments, the height of the partition plate is higher than the immersion liquid level of the medium oil area and lower than the top plate, so that the functional dry area and the medium oil area are in air communication.

[0024] In some possible embodiments, an explosion-proof valve is further included;

[0025] The explosion-proof valve is arranged on a side plate corresponding to the functional dry area, and the explosion-proof valve is communicated with the functional dry area.

[0026] In some possible embodiments, a limiting beam is further included;

[0027] The limiting beam is arranged on the liquid cooling base plate to fix the battery module on the liquid cooling base plate.

[0028] In the immersed liquid-cooled battery pack of the embodiment of the present invention, the immersion medium is sealed and stationary inside the battery pack, thereby avoiding leakage problems caused by the flow of the immersion medium in the pipeline, and avoiding local flow "dead zone" problems, turbulence problems, and inconsistent liquid pressure problems at different heights caused by the flow of the medium. At the same time, there is no material exchange between battery packs, and the scope of pollution accidents can be controlled within a single battery pack.

[0029] Furthermore, the submerged liquid-cooled battery pack of the present invention, by immersing the battery module within the immersion medium within the dielectric oil zone, allows heat to be dissipated from all surfaces of each cell in the battery module. This increases the heat dissipation area, enhances the battery's heat exchange capacity, and improves the temperature consistency of the battery during charging and discharging. Furthermore, by providing a liquid-cooled baseplate and cooling tube assembly at the bottom and top of the battery module, respectively, the temperature difference between the top and bottom of the battery can be significantly balanced. Since all battery surfaces are in continuous contact with the immersion medium, the generated heat can be promptly dissipated. The heat from the immersion medium is then dissipated through the cooling tube assembly and liquid-cooled baseplate, resulting in high overall efficiency and good uniformity.

[0030] Furthermore, the immersed liquid-cooled battery pack of the embodiment of the present invention isolates oxygen by immersing all battery modules in an immersion medium (such as an insulating liquid). In extreme cases such as thermal runaway of the battery, combustion will not occur when flammable gases such as hydrogen and carbon monoxide are ejected. Moreover, when the flammable gas bubbles rise in the insulating liquid, they fully exchange heat with the insulating liquid, and the temperature is reduced when entering the gas space, and it is not easy to burn when entering the atmosphere. The safety of the battery energy storage system in extreme situations is effectively improved. At the same time, the dangerous factors are controlled within a single package, and there is no risk of proliferation.

[0031] Furthermore, the immersed liquid-cooled battery pack of the embodiment of the present invention separates the enclosed space inside the battery box shell into a dielectric oil area and a functional dry area through a partition plate, so that the dielectric oil area can store battery modules, and the remaining components are placed in the functional dry area to achieve "dry-wet separation", avoiding reliability problems caused by long-term immersion of non-heat-generating components, and at the same time facilitating maintenance. BRIEF DESCRIPTION OF THE DRAWINGS

[0032] In order to more clearly illustrate the specific embodiments of the present invention or the technical solutions in the prior art, the following briefly introduces the drawings required for use in the specific embodiments or the description of the prior art. Obviously, the drawings described below are some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0033] Figure 1 This is a schematic structural diagram of an immersion liquid-cooled battery pack according to an embodiment of the present invention;

[0034] Figure 2 for Figure 1 A top view of the immersed liquid-cooled battery pack shown in;

[0035] Figure 3 for Figure 1 Front view of the immersion liquid-cooled battery pack shown in. DETAILED DESCRIPTION

[0036] To enable those skilled in the art to better understand the technical solutions of the present invention, the present invention is further described below in conjunction with the accompanying drawings and specific embodiments. It is apparent that the described embodiments are only a portion of the embodiments of the present invention, rather than all of them. Based on the described embodiments of the present invention, all other embodiments obtained by those skilled in the art without requiring creative effort are within the scope of protection of the present invention.

[0037] Unless otherwise specified, the technical terms or scientific terms used in the embodiments of the present invention should be understood by people with ordinary skills in the field to which the present invention belongs. The terms "including" or "comprising" used in the embodiments of the present invention neither limit the shapes, numbers, steps, actions, operations, components, originals and / or their groups mentioned, nor exclude the appearance or addition of one or more other different shapes, numbers, steps, actions, operations, components, originals and / or their groups, or the addition of these. In addition, the terms "first" and "second" are only used for descriptive purposes and cannot be understood as indicating or implying relative importance or implicitly indicating the number and order of the indicated technical features. Thus, the features defined as "first" and "second" may explicitly or implicitly include one or more of the features. In the description of the embodiments of the present invention, the meaning of "multiple" is two or more, unless otherwise clearly and specifically defined.

[0038] Unless otherwise specifically stated, the relative arrangements of the components and steps, numerical expressions, and numerical values set forth in these embodiments do not limit the scope of the present invention. At the same time, it should be understood that, for ease of description, the dimensions of the various parts shown in the drawings are not drawn in accordance with actual proportional relationships, and that the techniques, methods, and devices known to those of ordinary skill in the relevant art may not be discussed in detail, but where appropriate, the techniques, methods, and devices shown should be considered part of the authorized specification. In all examples shown and discussed herein, any specific other examples may have different values. It should be noted that similar symbols and letters represent similar items in the following figures, and therefore, once an item is defined in one figure, it does not need to be further discussed in subsequent figures.

[0039] In the description of the embodiments of the present invention, the description with reference to the terms "one embodiment", "some embodiments", "example", "specific example", or "some examples" means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present invention. In the embodiments of the present invention, the schematic representations of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described may be combined in any one or more embodiments or examples in a suitable manner. In addition, those skilled in the art may combine and combine different embodiments or examples described in the embodiments of the present invention and the features of different embodiments or examples, unless they are mutually inconsistent.

[0040] Below, the exemplary embodiments according to the present invention will be described in detail with reference to the accompanying drawings. Obviously, the described embodiments are only part of the embodiments of the present invention, rather than all the embodiments of the present invention, and it should be understood that the present invention is not limited to the exemplary embodiments described herein.

[0041] Figure 1 This is a schematic structural diagram of an immersion liquid-cooled battery pack according to an embodiment of the present invention; Figure 2 for Figure 1 A top view of the immersed liquid-cooled battery pack shown in; Figure 3 for Figure 1 Front view of the immersion liquid-cooled battery pack shown in.

[0042] like Figures 1 to 3As shown, an embodiment of the present invention relates to an immersion-type liquid-cooled battery pack, comprising: a battery module 1, a battery box shell 2, and a cooling pipe assembly. The battery box shell 2 comprises a liquid-cooled bottom plate (not marked in the figure), a top plate (not marked in the figure), a side plate (not marked in the figure) that forms a closed space with the liquid-cooled bottom plate and the top plate, and a partition plate 10 that divides the closed space into a dielectric oil area 11 and a functional dry area 12, wherein the dielectric oil area 11 is used to fill the immersion medium. The battery module 1 is located in the dielectric oil area 11 and is arranged on the liquid-cooled bottom plate. In some preferred embodiments, the battery modules are grouped in a manner of large-surface close contact, and no flow channels are arranged between the battery cells. This manner is conducive to providing the pre-tightening force required for the battery cell grouping. The cooling pipe assembly is arranged on the side of the battery module 1 away from the liquid-cooled bottom plate, and the cooling pipe assembly and the liquid-cooled bottom plate are both used to fill the cooling medium.

[0043] In the immersed liquid-cooled battery pack of the embodiment of the present invention, the immersion medium is sealed and stationary inside the battery pack, thereby avoiding leakage problems caused by the flow of the immersion medium in the pipeline, and avoiding local flow "dead zone" problems, turbulence problems, and inconsistent liquid pressure problems at different heights caused by the flow of the medium. At the same time, there is no material exchange between battery packs, and the scope of pollution accidents can be controlled within a single battery pack.

[0044] Furthermore, the submerged liquid-cooled battery pack of the present invention, by immersing the battery module within the immersion medium within the dielectric oil zone, allows heat to be dissipated from all surfaces of each cell in the battery module. This increases the heat dissipation area, enhances the battery's heat exchange capacity, and improves the temperature consistency of the battery during charging and discharging. Furthermore, by providing a liquid-cooled baseplate and cooling tube assembly at the bottom and top of the battery module, respectively, the temperature difference between the top and bottom of the battery can be significantly balanced. Since all battery surfaces are in continuous contact with the immersion medium, the generated heat can be promptly dissipated. The heat from the immersion medium is then dissipated through the cooling tube assembly and liquid-cooled baseplate, resulting in high overall efficiency and good uniformity.

[0045] Furthermore, the immersed liquid-cooled battery pack of the embodiment of the present invention isolates oxygen by immersing all battery modules in an immersion medium (such as an insulating liquid). In extreme cases such as thermal runaway of the battery, combustion will not occur when flammable gases such as hydrogen and carbon monoxide are ejected. Moreover, when the flammable gas bubbles rise in the insulating liquid, they fully exchange heat with the insulating liquid, and the temperature is reduced when entering the gas space, and it is not easy to burn when entering the atmosphere. The safety of the battery energy storage system in extreme situations is effectively improved. At the same time, the dangerous factors are controlled within a single package, and there is no risk of proliferation.

[0046] Furthermore, the immersed liquid-cooled battery pack of the embodiment of the present invention separates the enclosed space inside the battery box shell into a dielectric oil area and a functional dry area through a partition plate, so that the dielectric oil area can store battery modules, and the remaining components are placed in the functional dry area to achieve "dry-wet separation", avoiding reliability problems caused by long-term immersion of non-heat-generating components, and at the same time facilitating maintenance.

[0047] For example, Figures 1 to 3 As shown, the cooling pipe assembly includes a coolant inlet 3, a coolant outlet 4, and a cooling pipe 5. The coolant inlet 3 and the coolant outlet 4 are both located on the side panel corresponding to the functional dry area 12. The cooling pipe 5 is located on the side of the battery module 1 facing away from the liquid-cooled base plate. The liquid inlet of the cooling pipe 5 is connected to the coolant inlet 3, and the liquid outlet of the cooling pipe 5 is connected to the coolant outlet 4.

[0048] Specifically, in order to improve the heat exchange efficiency between the cooling tube assembly and the immersion medium, as Figures 1 to 3 As shown, the cooling tube 5 includes a first cooling sub-tube (not labeled in the figure), a second cooling sub-tube (not labeled in the figure) spaced apart from the first cooling sub-tube, and an arcuate cooling sub-tube (not labeled in the figure) connected to the first and second cooling sub-tubes, respectively. The inlet of the first cooling sub-tube is connected to the coolant inlet 3, and the outlet of the second cooling sub-tube is connected to the coolant outlet 4. In some preferred embodiments, the cooling tube 5 can be a serpentine cooling tube.

[0049] For example, in order to facilitate the filling and draining of the immersion medium into the medium oil area 11, as shown in FIG. Figures 1 to 3 As shown, the immersed liquid-cooled battery pack of the embodiment of the present invention further includes an oil filling and draining port 9 , which is arranged on a side panel corresponding to the functional dry area 12 , and the oil filling and draining port 9 is connected to the medium oil area 11 .

[0050] For example, in order to balance the pressure inside and outside the medium oil area during oil injection, Figures 1 to 3 As shown, the immersed liquid-cooled battery pack of the embodiment of the present invention further includes a pressure relief hole 7. The pressure relief hole 7 is provided on the side plate corresponding to the functional dry area 12, and the pressure relief hole 7 is connected to the medium oil area 11.

[0051] For example, in order to facilitate observation of the oil filling level in the medium oil area 11, as shown in FIG. Figures 1 to 3 As shown, the immersed liquid-cooled battery pack of the embodiment of the present invention further includes an oil indicator port 6; the oil indicator port 6 is arranged on the side panel corresponding to the functional dry area 12, and the height of the oil indicator port 6 is flush with the preset immersion liquid level of the medium oil area 11, so that when the oil is filled to the preset height, the oil indicator port 6 can see the corresponding liquid level.

[0052] Exemplarily, in order to facilitate air communication between the functional dry area 12 and the medium oil area 11, the height of the partition plate 10 is higher than the immersion liquid level of the medium oil area 11 and lower than the top plate, so that the functional dry area 12 and the medium oil area 11 form air communication.

[0053] For example, Figures 1 to 3 As shown, the submerged liquid-cooled battery pack according to the embodiment of the present invention further includes an explosion-proof valve 8. The explosion-proof valve 8 is disposed on a side panel corresponding to the functional dry area 12 and is in communication with the functional dry area 12. In this way, in the event of thermal runaway, pressure relief can be fully achieved through the explosion-proof valve 8 in the functional dry area 12.

[0054] For example, in order to facilitate the fixing of the battery module 1, Figures 1 to 3 As shown, the submerged liquid-cooled battery pack of the embodiment of the present invention further includes a limiting beam (not shown in the figure). The limiting beam is provided on the liquid-cooled base plate to secure the battery module 1 to the liquid-cooled base plate. The limiting beam secures the battery module 1, and the battery box housing 2 can be enlarged to accommodate battery modules 1 in different groupings as required.

[0055] It will be understood that the above embodiments are merely exemplary embodiments for illustrating the principles of the present invention, and the present invention is not limited thereto. Those skilled in the art will appreciate that various modifications and improvements can be made without departing from the spirit and substance of the present invention, and such modifications and improvements are also considered to be within the scope of protection of the present invention.

Claims

1. An immersion liquid-cooled battery pack, characterized in that: include: A battery box housing, the battery box housing comprising a liquid-cooled bottom plate, a top plate, a side plate forming a closed space with the liquid-cooled bottom plate and the top plate, and a partition plate dividing the closed space into a dielectric oil area and a functional dry area, the dielectric oil area being used to be filled with an immersion medium; a battery module, the battery module being located in the dielectric oil area and disposed on the liquid-cooled base plate; A cooling pipe assembly is provided on a side of the battery module away from the liquid-cooling base plate, and both the cooling pipe assembly and the liquid-cooling base plate are used to be filled with a cooling medium.

2. The immersion liquid-cooled battery pack according to claim 1, characterized in that: The cooling pipe assembly includes a cooling pipe, a coolant inlet and a coolant outlet; The coolant inlet and the coolant outlet are both provided on the side panels corresponding to the functional dry areas; The cooling pipe is arranged on a side of the battery module away from the liquid cooling base plate, the liquid inlet of the cooling pipe is communicated with the coolant inlet, and the liquid outlet of the cooling pipe is communicated with the coolant outlet.

3. The immersion liquid-cooled battery pack according to claim 2, characterized in that: The cooling pipe includes a first cooling sub-pipe, a second cooling sub-pipe spaced apart from the first cooling sub-pipe, and an arc-shaped cooling sub-pipe respectively connected to the first cooling sub-pipe and the second cooling sub-pipe; The inlet of the first cooling sub-tube is communicated with the coolant inlet, and the outlet of the second cooling sub-tube is communicated with the coolant outlet.

4. The immersion liquid-cooled battery pack according to claim 3, characterized in that: The cooling pipe is a serpentine cooling pipe.

5. The immersion liquid-cooled battery pack according to any one of claims 1 to 4, characterized in that: Also includes oil filling and drain ports; The oil filling and draining ports are arranged on the side plate corresponding to the functional dry area, and the oil filling and draining ports are communicated with the medium oil area.

6. The immersion liquid-cooled battery pack according to claim 5, characterized in that: Also includes a pressure relief hole; The pressure relief hole is provided on the side plate corresponding to the functional dry area, and the pressure relief hole is communicated with the medium oil area.

7. The immersion liquid-cooled battery pack according to claim 6, characterized in that: Also includes oil indicator port; The oil indicating port is arranged on the side plate corresponding to the functional dry area, and the height of the oil indicating port is flush with the preset immersion liquid level of the medium oil area.

8. The immersion liquid-cooled battery pack according to any one of claims 1 to 4, characterized in that: The height of the partition plate is higher than the immersion liquid level of the medium oil area and lower than the top plate, so that the functional dry area and the medium oil area are in air communication.

9. The immersion liquid-cooled battery pack according to claim 8, characterized in that: Also includes explosion-proof valves; The explosion-proof valve is arranged on a side plate corresponding to the functional dry area, and the explosion-proof valve is communicated with the functional dry area.

10. The immersion liquid-cooled battery pack according to any one of claims 1 to 4, characterized in that: Also included are limit beams; The limiting beam is arranged on the liquid cooling base plate to fix the battery module on the liquid cooling base plate.

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