An immersed direct-cooling energy storage device

Abstract

The patent application belongs to the technical field of energy storage equipment, and particularly relates to an immersed direct cooling energy storage equipment, which comprises a side cooling structure, the side cooling structure is in contact with the side wall of a battery module, a plurality of liquid inlet flow channels and liquid outlet flow channels are arranged in the side cooling structure, each of the liquid inlet flow channels and the liquid outlet flow channels is arranged along the side wall of the battery module one by one; when the direct cooling unit works, the refrigerant flows into the plurality of liquid inlet flow channels through the liquid inlet pipe, and then flows into the plurality of liquid outlet flow channels after passing through the two sides of each battery module one by one, and then flows back along the two sides of each battery module; the box is filled with immersion liquid, and the immersion liquid immerses the side cooling structure and the battery module; the purpose is to provide an immersed direct cooling energy storage equipment which has good temperature uniformity, high heat dissipation efficiency and prevents heat spread.

Description

Technical Field

[0001] This invention relates to the field of energy storage equipment technology, and specifically to an immersion direct-cooling energy storage device. Background Technology

[0002] A submersible battery pack is an energy storage device that directly immerses battery modules (composed of multiple cells) in a immersion liquid. During normal operation, the chemical reaction inside the cells causes the central area of ​​the cells to generate a large amount of heat. The cell tabs are the main channels for current to enter and exit, and a large amount of heat is also generated when a large current passes through them. Therefore, the main heat-generating area of ​​the battery pack is located in the upper middle part of the cells. Through direct contact between the immersion liquid and the cells, the heat in the upper middle part of the cells is quickly transferred to the immersion liquid, thereby ensuring the temperature uniformity inside the battery pack.

[0003] During operation, the temperature of the immersion fluid in a submerged battery pack continuously rises. Generally, either "bottom liquid cooling + static immersion" or "flowing immersion" is used. In the "bottom liquid cooling + static immersion" scheme, a liquid cooling plate is installed at the bottom of the battery pack. The upper surface of the liquid cooling plate contacts the immersion fluid and the bottom of the battery modules for heat dissipation. However, the heat-generating parts of the battery modules are concentrated in the upper and middle sections. Although the immersion fluid helps to even out the temperature, the bottom surface of the battery modules occupies most of the liquid cooling plate area, leaving only a small portion of the plate in contact with the immersion fluid, resulting in poor heat dissipation. In the "flowing immersion" scheme, the immersion fluid circulates directly within the battery pack. While this scheme provides better heat dissipation, the flowing immersion fluid puts greater pressure on the battery pack casing, requiring higher structural strength and sealing performance, thus increasing the cost of the casing materials. Summary of the Invention

[0004] In order to overcome the shortcomings of the prior art, the purpose of this invention is to provide an immersion direct cooling energy storage device with good temperature uniformity, high heat dissipation efficiency and prevention of heat spread.

[0005] The technical solution adopted in this invention is as follows:

[0006] An immersion direct-cooling energy storage device includes a battery pack, the battery pack including a housing and multiple battery modules installed in the housing, and a side-cooling structure that contacts the side wall of the battery modules. The side-cooling structure is provided with multiple liquid inlet channels and liquid outlet channels, each of the liquid inlet channels and liquid outlet channels being arranged sequentially around the side wall of the battery cells in the battery module.

[0007] When the direct cooling unit is working, the refrigerant flows into multiple liquid inlet channels, passes through both sides of each battery module in sequence, and then flows into multiple liquid outlet channels and back along both sides of each battery module.

[0008] The enclosure is filled with an immersion liquid that submerges the side-cooling structure and the battery module.

[0009] Compared with the prior art, the beneficial effects of the present invention are as follows:

[0010] 1. Both the inlet and outlet channels are in contact with the side wall of the battery module. Compared with the "bottom liquid cooling" solution, it is closer to the heat-generating area of ​​the battery module (the upper middle part of the battery module), resulting in better heat dissipation. The initial temperature of the refrigerant entering the battery pack is low, and the temperature rises continuously as it passes through the battery modules. Therefore, the temperature of the refrigerant flowing out of the battery pack is high. In this solution, both the inlet channel (lower refrigerant temperature) and the outlet channel (higher refrigerant temperature) pass through each battery pack, which can ensure the temperature uniformity of each battery module in a single battery pack.

[0011] 2. The tabs at the top of the battery module generate a lot of heat, but the immersion liquid submerges the battery module, and the heat near the tabs will be quickly transferred to the immersion liquid, achieving uniform temperature inside the battery pack. Since the immersion liquid submerges the entire side cooling structure, compared to the method of cooling only through the side cooling structure, the surfaces of the side cooling structure that are not in contact with the battery module will be in contact with the immersion liquid, which increases the heat exchange surface of the side cooling structure and improves the heat exchange efficiency.

[0012] 3. When the temperature of the battery module does not reach a certain value, the direct cooling unit will not work. At this time, the battery module is still heating up, which will cause a large temperature difference between the top and bottom of the battery module. In this solution, the immersion liquid can still achieve the effect of temperature equalization when the direct cooling unit is not working.

[0013] 4. Due to the flame-retardant and insulating properties of the immersion liquid, combined with the side-cooling structure for cooling, the temperature around the battery module in case of thermal runaway can be rapidly reduced, preventing thermal runaway from being triggered. If the battery module accidentally short-circuits, the surrounding insulating and flame-retardant immersion liquid isolates the oxygen required for combustion, extinguishing the localized combustion and thermal runaway that may be caused by the short circuit, thereby preventing the spread of heat. Therefore, the immersion liquid can play a role in fire protection.

[0014] 5. When the battery pack malfunctions and overheats, the internal pressure of the battery pack increases. In order to prevent the battery pack from exploding, the pressure relief valve on the battery pack will open and the electrolyte will flow out. In the "flow immersion" solution, the electrolyte will be mixed in the immersion liquid. Subsequent maintenance requires the replacement of all the immersion liquid in the circulation, which is costly. In this solution, only the immersion liquid in a single battery pack needs to be replaced.

[0015] 6. Compared to the "flow immersion" solution, the immersion liquid in this solution is static inside the battery pack, which reduces the requirements for the structural strength and sealing of the enclosure, saving material costs. In addition, this solution achieves better heat dissipation through the combination of immersion liquid and side cooling structure, which can also meet the heat dissipation requirements.

[0016] 7. Because the battery pack is filled with immersion fluid, condensation cannot be generated inside, thus solving the condensation problem caused by localized low temperatures in conventional battery packs;

[0017] 8. In the "bottom liquid cooling + static immersion" scheme, it is often half-immersion, and there is still a risk of heat spread due to the presence of oxygen inside. This scheme adopts "full immersion", which serves as an insulating and oxygen-barrier heat dissipation medium to reduce the temperature rise rate of a single cell when thermal runaway occurs. This suppresses the degree and time of thermal and boiling reactions inside the single cell, thereby suppressing the thermal runaway of the single cell and the heat spread between cells.

[0018] 9. In this solution, with "direct cooling + full immersion," even if the refrigerant leaks into the battery pack, the refrigerant in the direct cooling unit will not affect the conductivity of the immersion fluid. Compared to liquid cooling units (where leakage of the coolant would affect the conductivity of the immersion fluid and cause a short circuit between cells), there is no risk of a short circuit. Therefore, if "liquid cooling + full immersion" is used, the liquid cooling plate can only be placed on the outside of the battery pack housing to avoid short circuits caused by leakage. However, this solution can place the corresponding side cooling structure inside the battery pack and close to the cells, improving heat dissipation efficiency.

[0019] In a preferred embodiment of the present invention, the side cooling structure includes a side cooling plate, which is arranged around both sides of the battery module one by one, and multiple liquid inlet channels and liquid outlet channels are arranged inside the side cooling plate and arranged along the height direction of the side cooling plate.

[0020] The side cooling structure also includes an internal adapter, and the liquid outlet ends of the multiple liquid inlet channels and the liquid inlet ends of the liquid outlet channels are all interconnected through the internal adapter.

[0021] Beneficial effects:

[0022] 1. If multiple pipes are used as inlet and outlet channels, the pipes need to be inserted and fixed multiple times during installation. When welding pipes and joints, the position of each pipe and joint needs to be ensured, which is quite troublesome. However, the side cooling plate in this solution can be integrated into the side cooling plate by one-piece molding. During installation, only the side cooling plate and the inner adapter need to be installed, making the installation simpler and more convenient.

[0023] 2. Since both the inlet and outlet channels are located inside the side cooling plate, the inlet and outlet channels can exchange heat through the side cooling plate itself, resulting in a small temperature difference between the inlet and outlet of the refrigerant, thus ensuring the temperature uniformity of each battery module.

[0024] 3. In existing side-cooling structures, side-cooling plates are installed on the sides of each battery module. Each side-cooling plate has an inlet and an outlet at both ends. Multiple branch pipes of the liquid cooling pipeline are welded to each inlet to form multiple side-cooling plates in parallel. Although the above-mentioned parallel side-cooling structure can concentrate heat dissipation on the side walls of the battery modules compared to the "bottom liquid cooling" method, the parallel pipes cause internal coolant to be divided, which may lead to uneven flow and uneven heating and cooling of each battery module inside the battery pack. In contrast, although the side-cooling structure in this solution is also a parallel structure, each branch channel needs to pass through all battery modules. Even if the flow is uneven in each branch channel, it will not affect the temperature uniformity inside the battery pack.

[0025] In a preferred embodiment of the present invention, the plurality of liquid inlet channels are located on the upper part of the side wall of the battery module, and the plurality of liquid outlet channels are located on the lower part of the side wall of the battery module.

[0026] Beneficial effects: The heat-generating area of ​​the battery module is mainly in the upper middle part. The coolant temperature in the liquid inlet channel is relatively low, which makes it close to the upper middle part of the side wall of the battery module. Combined with the temperature uniformity effect of the immersion liquid, the temperature uniformity inside the battery pack is further guaranteed.

[0027] In a preferred embodiment of the present invention, the side-cooling structure further includes an external adapter, which is installed on the front side of the housing. The external adapter is provided with a liquid inlet and a liquid outlet. The liquid inlet is connected to the liquid inlet pipe of the direct-cooling unit, and the liquid outlet is connected to the liquid outlet pipe of the direct-cooling unit. The liquid inlet ends of the multiple liquid inlet channels are all connected to the liquid inlet, and the liquid outlet ends of the multiple liquid outlet channels are all connected to the liquid outlet.

[0028] In a preferred embodiment of the present invention, the side cold plate is made of aluminum extrusion metal plate.

[0029] Beneficial effects: Existing parallel side-cooling structures, which use plastic pipes, can only be used for water cooling. Compared with plastic pipes, aluminum extrusion metal plates have higher structural strength and can therefore adapt to the pressure during refrigerant flow.

[0030] Beneficial effects: In existing parallel side-cooling structures, the inlet and outlet pipes are located on the front and rear sides of the enclosure, and the outlet pipe needs to be routed around to the back of the battery pack to connect to the outlet, making the pipeline layout more complex and increasing the required pipe length. During maintenance, it may also be necessary to open the back panel of the battery cabinet. In this solution, by setting up an external adapter, the inlet and outlet ends of the side-cooling structure are in the same position, making it easier to connect to the direct-cooling unit without increasing the pipeline length, and making maintenance more convenient. Existing parallel side-cooling structures require two through holes in the enclosure to install the inlet and outlet pipes. In this solution, only a single through hole is needed in the enclosure to install the external adapter. Fewer through holes result in higher structural strength of the enclosure and make it less prone to deformation.

[0031] In a preferred embodiment of the present invention, the external adapter includes an inner plate, an outer plate, and two sealing sleeves. The inner plate is installed on the inner wall of the housing, and the outer plate is installed on the outer wall of the housing. The inner plate has two conical holes opened laterally, and the two conical holes are respectively connected to multiple liquid inlet channels and liquid outlet channels. The outer plate has two first mounting holes opened laterally, corresponding to the two conical holes. The sealing sleeves pass through the corresponding first mounting holes, the outer wall of the housing, and the conical holes in sequence.

[0032] The inlet or outlet pipe of the direct cooling unit is fixedly connected to the corresponding sealing sleeve.

[0033] Beneficial effects: By setting a conical hole, the refrigerant in the inlet and outlet channels can be collected and then flow into or out through the inlet pipe. In addition, the sealing sleeve itself is elastic and can be tightened in the conical hole. Therefore, it can be quickly inserted and removed during installation and disassembly.

[0034] In a preferred embodiment of the present invention, the housing includes a bottom plate and a top cover. The top cover is detachably mounted on the bottom plate. Both the outer plate and the inner plate are provided with a second mounting hole, and a screw passing through the side wall of the top cover is provided in the second mounting hole.

[0035] Beneficial effects: During installation, the outer panel, top cover, and inner panel are secured with screws, facilitating easy assembly and disassembly. Furthermore, the inner and outer panels seal the through holes for screws and sealing sleeves, ensuring the enclosure's airtightness.

[0036] As a preferred embodiment of the present invention, it further includes a cabinet and a direct cooling unit. The direct cooling unit is connected to an inlet pipe and an outlet pipe. The inlet pipe and the outlet pipe are both located on the same side of the cabinet. The external adapter is located on the side of the battery pack near the inlet pipe and the outlet pipe. The inlet pipe and the outlet pipe are each provided with multiple branch pipes that communicate with the corresponding external adapter.

[0037] Beneficial effects:

[0038] 1. The inlet and outlet pipes are both located on the same side of the cabinet and close to the external adapter, which reduces the required branch pipe length, lowers equipment costs, and makes the cabinet wiring distribution simpler. When it is necessary to disassemble the battery pack and corresponding pipes for maintenance, only the single external adapter of the corresponding battery pack needs to be disassembled to open the top cover.

[0039] 2. Both the inlet and outlet pipes are located on the same side of the cabinet. A single through hole can be opened on the cabinet to simultaneously install the inlet and outlet pipes, making installation simpler, reducing the number of openings in the cabinet, and simplifying the cabinet processing steps. Attached Figure Description

[0040] Figure 1 This is a schematic diagram of the structure of Embodiment 1 of the immersion direct-cooling energy storage device of the present invention;

[0041] Figure 2 This is a schematic diagram of the side-cooling structure in Embodiment 1 of the immersion direct-cooling energy storage device of the present invention;

[0042] Figure 3 This is a schematic diagram of the internal structure of the side-cooling structure in Embodiment 1 of the immersion direct-cooling energy storage device of the present invention.

[0043] The reference numerals in the attached drawings include: cabinet 1, direct cooling unit 11, liquid inlet pipe 12, liquid outlet pipe 13, box 14, side cooling plate 21, liquid inlet channel 211, liquid outlet channel 212, inner adapter 22, outer adapter 23, inner plate 231, outer plate 232, sealing sleeve 233, conical hole 234, first mounting hole 235, and second mounting hole 236. Detailed Implementation

[0044] Typical embodiments embodying the features and advantages of the present invention will be specifically described in the following description. It should be understood that the present invention can have various variations in different embodiments without departing from the scope of the present invention, and the descriptions and illustrations herein are for illustrative purposes only and not intended to limit the present invention.

[0045] In the description of this application, the terms "first", "second", etc. are used only for the convenience of describing this application and simplifying the description, and are not intended to indicate or imply that the structure referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of this application.

[0046] Example 1:

[0047] See Figure 1As shown, the submersible direct-cooling energy storage device of this embodiment includes a cabinet 1. The lower part of the cabinet 1 is an electrical compartment, and the upper part is a battery compartment. A direct-cooling unit 11 is installed in the electrical compartment, and multiple battery packs are vertically installed in the electrical compartment. Each battery pack is equipped with a side-cooling structure. The direct-cooling unit 11 is connected to an inlet pipe 12 and an outlet pipe 13 for circulating refrigerant. The inlet pipe 12 and the outlet pipe 13 are located on the same side of the cabinet 1. Multiple branch pipes connected to the corresponding side-cooling structures are provided on the inlet pipe 12 and the outlet pipe 13. The battery pack includes a housing 14 and multiple battery modules installed in the housing 14. The housing 14 includes a top cover and a bottom plate. The top cover is detachably installed on the bottom plate.

[0048] Among them, see Figure 2 As shown, the side-cooling structure includes a side-cooling plate 21, an inner adapter 22, and an outer adapter 23. The side-cooling plate 21 is integrally formed and is arranged around both sides of the battery module. Multiple liquid inlet channels 211 and liquid outlet channels 212 are disposed within the side-cooling plate 21 and arranged along the height direction of the side-cooling plate 21. The multiple liquid inlet channels 211 are located at the upper part of the side wall of the battery module, and the multiple liquid outlet channels 212 are located at the lower part of the side wall of the battery module. The liquid outlet end of liquid flow channel 211 and the liquid inlet end of liquid flow channel 212 are interconnected through internal adapter 22; the external adapter 23 is installed on the front side of the housing 14, and the external adapter 23 is provided with a liquid inlet and a liquid outlet. The liquid inlet is connected to the liquid inlet pipe 12 of the direct cooling unit 11, and the liquid outlet is connected to the liquid outlet pipe 13 of the direct cooling unit 11. The liquid inlet ends of multiple liquid flow channels 211 are all connected to the liquid inlet, and the liquid outlet ends of multiple liquid flow channels 212 are all connected to the liquid outlet.

[0049] Among them, see Figure 3 As shown, the external adapter 23 includes an inner plate 231, an outer plate 232, and two sealing sleeves 233. The inner plate 231 is installed on the inner wall of the housing 14, and the outer plate 232 is installed on the outer wall of the housing 14. The inner plate 231 has two conical holes 234 opened laterally, which are respectively connected to multiple liquid inlet channels 211 and liquid outlet channels 212. The outer plate 232 has two first mounting holes 235 corresponding to the two conical holes 234. The sealing sleeves 233 pass through the corresponding first mounting holes 235, the outer wall of the housing 14, and the conical holes 234 in sequence. The liquid inlet pipe 12 or liquid outlet pipe 13 of the direct cooling unit 11 is fixedly connected to the corresponding sealing sleeves 233. Both the outer plate 232 and the inner plate 231 are provided with second mounting holes 236, and screws that pass through the side wall of the upper cover are provided in the second mounting holes 236.

[0050] Example 2:

[0051] Based on Embodiment 1, there is a gap between each cell in a single battery module, the sidewall between cells is a large surface, a vertical row of cells constitutes a battery module, the side cooling plate 21 can pass vertically through the side of a single cell, and then be horizontally wrapped around the large surface of a single or multiple cells, and then be vertically wrapped around a single cell, and then continue to be horizontally wrapped until it passes through all cells.

[0052] The above embodiments are merely preferred embodiments of the present invention and should not be construed as limiting the scope of protection of the present invention. Any non-substantial changes and substitutions made by those skilled in the art based on the present invention shall fall within the scope of protection claimed by the present invention.

Claims

1. A submersible direct-cooling energy storage device, comprising a battery pack, the battery pack including a housing and a plurality of battery modules installed inside the housing, characterized in that: It also includes a side cooling structure, which is in contact with the side wall of the battery module. The side cooling structure is provided with multiple liquid inlet channels and liquid outlet channels, and each of the liquid inlet channels and liquid outlet channels is arranged around the side wall of the battery cell in the battery module. When the direct cooling unit is working, the refrigerant flows into multiple inlet channels through the inlet pipe, passes through both sides of each battery module in sequence, and then flows into multiple outlet channels and back along both sides of each battery module. The enclosure is filled with an immersion liquid that submerges the side-cooling structure and the battery module. The side cooling structure includes a side cooling plate, which is arranged around both sides of the battery module. Multiple liquid inlet channels and liquid outlet channels are arranged inside the side cooling plate and along the height direction of the side cooling plate. The side cooling structure also includes an internal adapter, and the liquid outlet ends of the multiple liquid inlet channels and the liquid inlet ends of the liquid outlet channels are all interconnected through the internal adapter. The side-cooling structure also includes an external adapter, which is installed on the front side of the housing. The external adapter is provided with a liquid inlet and a liquid outlet. The liquid inlet is connected to the liquid inlet pipe of the direct cooling unit, and the liquid outlet is connected to the liquid outlet pipe of the direct cooling unit. The liquid inlet ends of multiple liquid inlet channels are all connected to the liquid inlet, and the liquid outlet ends of multiple liquid outlet channels are all connected to the liquid outlet. The external adapter includes an inner plate, an outer plate, and two sealing sleeves. The inner plate is installed on the inner wall of the housing, and the outer plate is installed on the outer wall of the housing. The inner plate has two conical holes opened laterally, which are respectively connected to multiple liquid inlet channels and liquid outlet channels. The outer plate has two first mounting holes opened laterally, which correspond to the two conical holes. The sealing sleeves pass through the corresponding first mounting holes, the outer wall of the housing, and the conical holes in sequence. The inlet or outlet pipe of the direct cooling unit is fixedly connected to the corresponding sealing sleeve.

2. The submersible direct-cooling energy storage device according to claim 1, characterized in that: The plurality of liquid inlet channels are located on the upper part of the side wall of the battery module, and the plurality of liquid outlet channels are located on the lower part of the side wall of the battery module.

3. The submersible direct-cooling energy storage device according to claim 1, characterized in that: The side cooling plate is made of aluminum extrusion metal sheet.

4. The submersible direct-cooling energy storage device according to claim 1, characterized in that: The housing includes a bottom plate and a top cover. The top cover is detachably mounted on the bottom plate. Both the outer and inner plates are provided with a second mounting hole, and a screw passing through the side wall of the top cover is provided in the second mounting hole.

5. The submersible direct-cooling energy storage device according to claim 1, characterized in that: It also includes a cabinet and a direct cooling unit. The direct cooling unit is connected to an inlet pipe and an outlet pipe. The inlet pipe and the outlet pipe are both located on the same side of the cabinet. The external adapter is located on the side of the battery pack near the inlet pipe and the outlet pipe. The inlet pipe and the outlet pipe are each provided with multiple branch pipes that communicate with the corresponding external adapter.

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