Cooling liquid flow self-adjusting spraying device for energy storage battery

Abstract

The utility model relates to the technical field of batteries, in particular to an energy storage battery cooling liquid flow self-adjusting spraying device which comprises a battery box, a battery module and a spraying structure. The spraying structure comprises a liquid accumulation tank which is fixed on the battery box and is positioned above the battery module; the outer spraying arms are fixed on the two sides of the liquid accumulation tank; the outer spraying arm is hollow and is downwards provided with a plurality of spraying openings; the inner spraying arm is arranged in the outer spraying arm, the density of the inner spraying arm is lower than that of the cooling liquid, and the inner spraying arm is hollow and is downwards connected with a variable-diameter spraying nozzle; the spray nozzles and the spray ports on the outer spray arm are inserted to form variable-diameter spray ports, the variable-diameter spray ports are uniformly distributed above the gaps of the battery cells, the closer the variable-diameter spray ports are to the liquid accumulation tank, the smaller the gaps between the spray nozzles and the spray ports are, and otherwise, the larger the gaps between the spray nozzles and the spray ports are. Through the design of the spraying structure, the flow self-regulation is realized, the problem of uneven temperature layering is avoided, and meanwhile, the thermal runaway of the battery cell can be effectively treated.

Description

Technical Field

[0001] The utility model relates to the technical field of batteries, in particular to a self-regulating spray device for cooling liquid flow of energy storage batteries. Background Art

[0002] New power generation methods, such as wind, solar, tidal, and geothermal energy, are being fully utilized according to their location, gradually replacing traditional coal-fired power and reducing atmospheric pollution. The rapid development of these new power generation methods has promoted the application of energy storage technology. However, battery energy storage is limited by its high energy density, resulting in increasing heat generation and a higher risk of thermal runaway. Therefore, it is crucial to more effectively control the temperature rise of battery cells and effectively prevent thermal runaway.

[0003] Immersion liquid cooling is a rapidly developing technology designed to address the aforementioned operating conditions. By directly immersing the battery in insulating coolant, the heat generated by the battery is transferred to the insulating coolant and then directed to the outside world for heat transfer, thereby controlling the battery's reasonable temperature rise. Compared to traditional air cooling and liquid cooling technologies, immersion liquid cooling offers advantages in cooling efficiency and safety. However, the insulating coolant used in immersion liquid cooling suffers from uneven temperature stratification in actual operation. This means that after absorbing the heat from the battery, the insulating coolant's density decreases and it gathers upward, resulting in a higher temperature, while the insulating coolant below is relatively cooler. Furthermore, there are issues such as high production cost and high density, which significantly increases the weight and cost of the entire battery module. Utility Model Content

[0004] The purpose of this utility model is to overcome the shortcomings of the existing technology and propose to design a self-regulating spray device for energy storage battery coolant flow, which uses less insulating coolant and has a simpler piping structure, so that the battery module can obtain good temperature uniformity with the shortest thermal conduction path, avoiding the problem of uneven temperature stratification.

[0005] The technical solution adopted by the utility model to solve its technical problems is:

[0006] A self-regulating spray device for cooling liquid of an energy storage battery, comprising:

[0007] A battery box, used to accommodate a plurality of the battery modules and the spray structure;

[0008] The battery module has cells arranged inside, and coolant flow channels are preset between adjacent cells so that the sprayed coolant can quickly conduct heat along the flow channel direction;

[0009] Spray structure, including:

[0010] The liquid storage tank is fixed on the battery box and located above the battery module;

[0011] The outer spray arm is fixed on both sides of the liquid sump, and the bottom height of the outer spray arm is higher than the inner wall of the bottom of the liquid sump; the outer spray arm is hollow inside and has a plurality of spray ports downwardly opened;

[0012] The inner spray arm, located inside the outer spray arm, has a lower density than the coolant. The inner spray arm is hollow and connected downward to a number of variable-diameter spray nozzles, the same number as the outer spray arm's spray outlets. The inner spray arm's spray nozzles extend from the outer spray arm's spray outlets, interlaced with the spray nozzles on the outer spray arm to form variable-diameter spray outlets. These variable-diameter spray outlets are evenly distributed above the gaps between the battery cells. The closer the variable-diameter spray outlets are to the liquid accumulation tank, the smaller the gap between them, and vice versa. When the coolant enters the outer spray arm and the liquid level continues to rise, the inner spray arm floats upward because the inner spray arm's density is lower than the coolant's density, adjusting the flow rate of the variable-diameter spray outlets to ensure a similar coolant flow rate at each outlet.

[0013] In the above technical solution, the spray structure can ensure that each battery module in the battery box obtains a balanced spray volume, and when the battery cell suffers thermal runaway, the liquid accumulation tank of the spray structure will release all the coolant after being heated and melted, thereby achieving full immersion fire protection treatment of the battery module.

[0014] Furthermore, the several spray nozzles on the inner spray arm are arranged in sequence from the side away from the liquid accumulation tank to the side close to the liquid accumulation tank; during the floating process of the inner spray arm, the gap between the spray nozzle and the spray nozzle of the outer spray arm gradually decreases; the gap between the spray nozzle on the inner spray arm from the spray nozzle close to the liquid accumulation tank to the spray nozzle far from the liquid accumulation tank and the spray nozzle of the outer spray arm gradually increases. In the process of the coolant flowing to the end of the outer spray arm, the flow rate of the spray nozzle it passes through first is large and the gap is small, and the flow rate of the spray nozzle it passes through later is small and the gap is large, so that the flow rate of the coolant sprayed by each spray nozzle is similar, thereby realizing flow regulation and ensuring the temperature balance of the battery cell.

[0015] Furthermore, an eight-shaped variable diameter protrusion is provided on the spray nozzle of the inner spray arm, and the height of the variable diameter protrusion increases successively from the spray nozzle far away from the liquid accumulation tank to the spray nozzle close to the liquid accumulation tank, so that during the floating process of the inner spray arm, the gap between the spray nozzle of the inner spray arm from the spray nozzle close to the liquid accumulation tank to the spray nozzle far away from the liquid accumulation tank and the spray mouth of the outer spray arm gradually increases.

[0016] Furthermore, the battery box is provided with a coolant inlet on the top, a coolant accumulation pool and a coolant outlet located at the bottom of the accumulation pool at the bottom.

[0017] Furthermore, the diameter of the liquid inlet is larger than the diameter of the liquid outlet, ensuring that part of the coolant is stored in the liquid accumulation pool.

[0018] Furthermore, the outer spray arm is in the shape of a hollow tube, with one end away from the liquid accumulation tank being closed by an end cover, and the other end close to the liquid accumulation tank being fixed to the liquid accumulation tank.

[0019] Furthermore, the inner spray arm is in a hollow tubular shape with both ends being open.

[0020] Furthermore, the liquid accumulation groove is configured as a notch having a T-shaped, V-shaped, U-shaped or trapezoidal structure in longitudinal section.

[0021] Furthermore, the coolant is one of perfluorohexene, perfluorononene or perfluorocarbon compounds.

[0022] Furthermore, a plurality of the liquid inlets are connected in parallel and communicated with the main liquid inlet line, and the coolant is diverted from the main liquid inlet line to the liquid inlet of the battery box.

[0023] Technical effects of this utility model:

[0024] Compared with existing technologies, the spray structure design of this utility model achieves self-regulation of flow, avoids the problem of uneven temperature stratification, and can effectively deal with thermal runaway of battery cells. This utility model has a simpler piping structure, can reduce the use of insulating coolant, and save costs. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] Figure 1 This is a schematic diagram of the structure of the energy storage battery coolant flow self-regulating spray device of the utility model;

[0026] Figure 2 This is an isometric drawing of the spray structure of the utility model;

[0027] Figure 3 This is a cross-sectional view of the spray structure of the utility model along the spray arm;

[0028] Figure 4 This is a schematic diagram of the structure of the inner and outer spray arms of the spray structure of the utility model;

[0029] Figure 5 This is a schematic diagram of the structure of the outer spray arm spray port and the inner spray arm spray nozzle of the spray structure of the utility model, wherein Figure (a) is a schematic diagram of the structure of spray port one and spray nozzle one, Figure (b) is a schematic diagram of the structure of spray port two and spray nozzle two, and Figure (c) is a schematic diagram of the structure of spray port three and spray nozzle three.

[0030] In the figure, 1. battery box; 2. battery module; 3. spray structure; 4. coolant; 5. liquid inlet; 6. liquid outlet; 7. liquid accumulation pool;

[0031] 31. Liquid accumulation tank; 32. External spray arm; 33. Internal spray arm; 34. End cover; 35. Variable diameter protrusion;

[0032] 321, spray port 1; 322, spray port 2; 323, spray port 3;

[0033] 331. Spray nozzle one; 332. Spray nozzle two; 333. Spray nozzle three. DETAILED DESCRIPTION

[0034] In order to make the purpose, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention are clearly and completely described below in conjunction with the accompanying drawings.

[0035] Example 1:

[0036] like Figure 1 As shown, this embodiment involves a self-regulating spray device for cooling liquid 4 of an energy storage battery, comprising: a battery box 1, a battery module 2, a spray structure 3, cooling liquid 4, a liquid inlet 5, a liquid outlet 6 and a liquid accumulation pool 7.

[0037] like Figure 1 As shown, the battery box 1 is used to accommodate several of the battery modules 2 and the spray structure 3. A coolant inlet 5 is provided on the top, a coolant accumulation pool 7 and a coolant outlet 6 located at the bottom of the accumulation pool 7 are provided on the bottom. The diameter of the inlet 5 is larger than the diameter of the outlet 6 to ensure that part of the coolant 4 is stored in the accumulation pool 7.

[0038] Coolant flow channels are preset between the battery cells in the battery module 2, so that the sprayed coolant 4 can quickly conduct heat along the flow channel direction.

[0039] like Figure 2-5As shown, the spray structure 3 includes a liquid collection tank 31, an outer spray arm 32, an inner spray arm 33 and an end cover 34; the liquid collection tank 31 is fixed on the battery box 1 and is located above the battery module 2; the outer spray arm 32 is fixed on both sides of the liquid collection tank 31, and the bottom height of the outer spray arm 32 is higher than the bottom inner wall of the liquid collection tank 31. For example, in this embodiment, the liquid collection tank 31 is set to a notch with a T-shaped longitudinal section. The utility model is not limited to this structure, and the liquid collection tank 31 can also be set to a notch with a V-shaped, U-shaped, trapezoidal or other structures in the longitudinal section. The outer spray arm 32 is hollow inside and has several spray ports downwardly: spray port 1 321, spray port 2 322, and spray port 3 323; the inner spray arm 33 is placed inside the outer spray arm 32, the inner spray arm 33 is hollow inside, and is connected downwardly to variable-diameter spray nozzles with the same number as the spray ports of the outer spray arm 32: spray nozzle 1 331, spray nozzle 2 332, and spray nozzle 3 333; the spray nozzles of the inner spray arm 33 extend from the spray ports of the outer spray arm 32, and the spray nozzles on the outer spray arm 32 are interlaced with the spray ports to form variable-diameter spray ports. The closer the variable-diameter spray ports are to the liquid accumulation tank 31, the smaller the gap, and vice versa. The variable-diameter spray ports are evenly distributed above the gap between the battery cells; the density of the inner spray arm 33 is lower than the density of the coolant 4. When the coolant 4 enters the outer spray arm 32, as the liquid level continues to rise, the inner spray arm 33 also floats up. Both the outer spray arm 32 and the inner spray arm 33 are hollow tubular. The outer spray arm 32 is sealed at the end away from the liquid sump 31 by an end cap 34, while the end closer to the liquid sump 31 is fixed to the sump 31. Both ends of the inner spray arm 33 are open. The spray structure 3 not only directly cools the battery's larger thermally conductive surfaces by spraying, but also ensures a balanced spray volume for each battery module 2 within the battery box 1. Furthermore, it allows for full immersion of all battery modules 2 within the battery box 1 in the event of thermal runaway.

[0040] like Figure 2-5 As shown, the spray nozzle 1 331, the spray nozzle 2 332, and the spray nozzle 3 333 are arranged in sequence from the side away from the liquid accumulating tank 31 to the side close to the liquid accumulating tank 31. During the floating process of the inner spray arm 33, the gaps between the spray nozzle 2 332, the spray nozzle 3 333 and the spray port of the outer spray arm 32 gradually decrease, and the gap between the spray nozzle 1 331 and the spray port of the outer spray arm 32 remains unchanged; the gap between the spray nozzle of the inner spray arm 33 and the spray port of the outer spray arm 32 gradually increases from the side close to the liquid accumulating tank 31 to the side away from the liquid accumulating tank 31. In the process of the coolant 4 flowing to the end of the outer spray arm 32, the flow rate of the spray port through which it passes first is large and the gap is small, and the flow rate of the spray port through which it passes later is small and the gap is large, so that the flow rate of the coolant 4 sprayed by each spray port is similar, thereby realizing flow regulation and ensuring the temperature balance of the battery core. As a feasible implementation method, as Figure 5As shown, in this embodiment, both the second spray nozzle 332 and the third spray nozzle 333 are provided with a variable diameter protrusion 35 in an "eight" shape, and the heights of the variable diameter protrusions 35 on the second spray nozzle 332 and the third spray nozzle 333 are successively increased. The present invention is not limited to the above embodiment, and the variable diameter protrusions 35 in an "eight" shape can also be provided on the first spray nozzle 331, the second spray nozzle 332, and the third spray nozzle 333, and the heights of the variable diameter protrusions 35 on the first spray nozzle 331, the second spray nozzle 332, and the third spray nozzle 333 are successively increased, so that during the floating process of the inner spray arm 33, the gaps between the spray nozzles 1 331, the second spray nozzle 332, and the third spray nozzle 333 and the outer spray arm 32 are gradually reduced.

[0041] The coolant 4 of this embodiment has excellent flame retardancy and insulation properties, enabling cooling, heat preservation, preheating, insulation, and fire protection for the battery module 2. It also maintains good compatibility with other auxiliary materials within the battery box 1. The coolant 4 exhibits gas-liquid phase transition properties, absorbing heat upon vaporization in a liquid state. The coolant 4 can be selected from perfluorohexene, perfluorononene, or a perfluorocarbon compound.

[0042] The outer spray arm 32 , the inner spray arm 33 and the number of spray ports of the spray structure of the present invention can be adjusted according to the number of battery modules 2 inside the battery box 1 and the heating power.

[0043] The working principle of the structure described in this embodiment is as follows Figure 1As shown, after the coolant 4 is diverted from the main liquid inlet line to the liquid inlet 5 of the battery box 1, it is first injected into the liquid sump 31. As the liquid level of the liquid sump 31 gradually rises and reaches the bottom of the outer spray arm 32, the coolant 4 will flow in from the liquid inlet end of the outer spray arm 32. The coolant 4 that enters first will be sprayed from the gap between the spray port of the outer spray arm 32 and the spray nozzle of the inner spray arm 33. The spray volume is less than the flow of the coolant 4 entering the inner part of the outer spray arm 32, and the coolant 4 level continues to rise. At this time, the lower end of the outer part of the inner spray arm 33 contacts the lower end of the inner part of the outer spray arm 32. When the coolant 4 level gradually exceeds the bottom of the inner spray arm 33, part of the coolant 4 flows along the liquid inlet of the inner spray arm 33. In the process of flowing from the side close to the liquid sump 31 to the side away from the liquid sump 31, part of the coolant 4 is sprayed from the spray nozzle of the inner spray arm 33 to the battery cells in the battery module 2. The coolant 4 level continues to rise, and the coolant 4 in the outer spray arm 32 also increases. Since the structural density of the inner spray arm 33 is less than the density of the coolant 4, the inner spray arm 33 begins to float upward with the rise of the coolant 4 level in the outer spray arm 32. Finally, the outer upper end of the inner spray arm 33 is tangent to the inner upper end of the outer spray arm 32 and no longer floats up. The coolant 4 in the inner spray arm 33 continues to spray to the battery cell through the spray nozzle. Since the outer diameters of the several spray nozzles on the inner spray arm 33 are different, during the floating process, the spray nozzles of the inner spray arm 33 and the outer spray nozzles of the outer spray arm 32 are tangent to each other. The gap between the spray ports of the outer spray arm 32 gradually decreases, and the gap gradually increases from the side close to the liquid accumulation tank 31 to the side far from the liquid accumulation tank 31. In the process of flowing to the end of the outer spray arm 32, the coolant 4 will pass through the smaller gap first. The coolant 4 will be sprayed from this spray port first, and then gradually sprayed from other spray ports. In this process, the flow rate of the coolant 4 sprayed from each spray port is similar, and the gap sizes are different. The spray port that passes through first has a large flow rate and a small gap, and the spray port that passes through later has a small flow rate and a large gap. In this way, flow regulation is achieved to ensure the temperature balance of the battery cell.

[0044] As the coolant 4 continues to flow into the liquid inlet 5 of the battery box 1, but the amount of coolant sprayed by the spray structure 3 is far less than the amount of liquid inlet, the coolant 4 in the liquid accumulation tank 31 of the spray structure 3 is filled, and the liquid inlet main line can no longer distribute liquid to the spray structure 3, and the coolant flow rate of the liquid inlet main line to the next battery box 1 begins to increase. The coolant 4 collected in the liquid accumulation pool 7 at the bottom of the battery box 1 gradually flows from the liquid outlet 6 to the liquid outlet main line. Among them, the diameter of the liquid outlet 6 is smaller than the diameter of the liquid inlet 5, which can ensure that there is a certain amount of coolant 4 at the bottom of the battery box 1, ensuring that when the battery cell suffers thermal runaway, the liquid accumulation tank 31 of the spray structure 3 will be heated and melted to release all the coolant 4 to immerse the battery cell.

[0045] When the liquid level of the coolant 4 in the liquid storage tank 31 of the spray structure 3 drops, the inner spray arm 33 also sinks, and the main liquid inlet line starts to distribute liquid to the liquid inlet 5 of the battery box 1, and so on, realizing self-regulation of flow and effectively controlling the temperature of the battery cell.

[0046] The utility model realizes automatic adjustment of the spray volume in the battery box according to the coolant level in the liquid accumulation tank of the spray structure through the designed energy storage battery coolant flow self-regulating spray device and the size of the coolant inlet and outlet pipes, thereby solving the problems of cumbersome piping in traditional spray liquid-cooled battery boxes and power consumption of flow detection and control sensors.

[0047] This utility model is based on the design concept of directional spraying, recycling and phase change heat absorption. Compared with the traditional fully immersed energy storage battery system, it can circulate cooling or preheating of the insulating coolant according to the cooling capacity or preheating requirements of the energy storage battery system, and the flow self-regulating spray structure design for the larger heat conductive surface of the battery cell has the beneficial effect of significantly reducing the amount of insulating coolant used.

[0048] The above-mentioned specific implementation methods are only specific cases of the present utility model. The patent protection scope of the present utility model includes but is not limited to the above-mentioned specific implementation methods. Any appropriate changes or modifications made to them by ordinary technicians in the relevant technical field that comply with the claims of the present utility model shall fall within the patent protection scope of the present utility model.

Claims

1. A self-regulating spray device for cooling liquid of energy storage battery, characterized in that: include: A battery box (1) for accommodating a plurality of battery modules (2) and a spray structure (3); A battery module (2) is provided with battery cells therein, and coolant (4) flow channels are preset between adjacent battery cells; Spray structure (3), including: A liquid storage tank (31) is fixed to the battery box (1) and is located above the battery module (2); The outer spray arm (32) is fixed on both sides of the liquid accumulation tank (31), and the bottom height of the outer spray arm (32) is higher than the bottom inner wall of the liquid accumulation tank (31); the outer spray arm (32) is hollow inside and has a plurality of spray ports opened downward; The inner spray arm (33) is placed inside the outer spray arm (32) and has a density lower than that of the coolant (4). The inner spray arm (33) is hollow and is connected downward to variable-diameter spray nozzles having the same number as the spray nozzles of the outer spray arm (32). The spray nozzles of the inner spray arm (33) extend from the spray nozzles of the outer spray arm (32). The spray nozzles on the outer spray arm (32) are interlaced with the spray nozzles to form variable-diameter spray nozzles. The variable-diameter spray nozzles are evenly distributed above the gap between the battery cells. The closer the variable-diameter spray nozzles are to the liquid accumulation tank (31), the smaller the gap between the spray nozzles and the spray nozzles, and vice versa.

2. The energy storage battery coolant flow self-regulating spray device according to claim 1, characterized in that: The plurality of spray nozzles on the inner spray arm (33) are sequentially arranged from the side away from the liquid accumulation tank (31) to the side close to the liquid accumulation tank (31); during the floating process of the inner spray arm (33), the gap between the spray nozzle and the spray port of the outer spray arm (32) gradually decreases; the gap between the spray nozzle on the inner spray arm (33) from the spray nozzle close to the liquid accumulation tank (31) to the spray nozzle away from the liquid accumulation tank (31) and the spray port of the outer spray arm (32) gradually increases.

3. The energy storage battery coolant flow self-regulating spray device according to claim 2, characterized in that: The spray nozzles of the inner spray arm (33) are all provided with a variable diameter protrusion (35) of an eight-shaped structure, and the height of the variable diameter protrusion (35) on the spray nozzle far from the liquid accumulation groove (31) to the spray nozzle close to the liquid accumulation groove (31) is gradually increased, so that when the inner spray arm (33) floats up, the gap between the spray nozzle of the inner spray arm (33) from the spray nozzle close to the liquid accumulation groove (31) to the spray nozzle far from the liquid accumulation groove (31) and the spray nozzle of the outer spray arm (32) gradually increases.

4. The energy storage battery coolant flow self-regulating spray device according to claim 1, characterized in that: The battery box (1) is provided with a liquid inlet (5) at the top, and a coolant (4) liquid accumulation pool (7) and a coolant (4) liquid outlet (6) located at the bottom of the liquid accumulation pool (7) at the bottom.

5. The energy storage battery coolant flow self-regulating spray device according to claim 4, characterized in that: The diameter of the liquid inlet (5) is larger than the diameter of the liquid outlet (6).

6. The energy storage battery coolant flow self-regulating spray device according to claim 1, characterized in that: The outer spray arm (32) is in the shape of a hollow tube, with one end away from the liquid accumulating tank (31) being closed by an end cover (34), and the other end close to the liquid accumulating tank (31) being fixed to the liquid accumulating tank (31).

7. The energy storage battery coolant flow self-regulating spray device according to claim 1, characterized in that: The inner spray arm (33) is in a hollow tubular shape, with both ends being open.

8. The energy storage battery coolant flow self-regulating spray device according to claim 1, characterized in that: The liquid accumulation groove (31) is configured as a notch with a longitudinal cross-section having a T-shaped, V-shaped, U-shaped or trapezoidal structure.

9. The energy storage battery coolant flow self-regulating spray device according to claim 1, characterized in that: The coolant (4) is one of perfluorohexene, perfluorononene or perfluorocarbon compounds.

10. The energy storage battery coolant flow self-regulating spray device according to claim 4 or 5, characterized in that: Several of the liquid inlets (5) are connected in parallel and communicated with the main liquid inlet line.

Images