A water-immersed energy storage battery box integrated system

Abstract

This invention discloses a water-immersed energy storage battery box integrated system, including a submersible energy storage battery box, a heat exchanger, an ultrapure water generator, and a storage tank. The coolant outlet of the water-immersed energy storage battery box is connected to the inlet of the storage tank, the outlet of the storage tank is connected to the inlet of the ultrapure water generator, the outlet of the ultrapure water generator is connected to the inlet of the heat exchanger, and the outlet of the heat exchanger is connected to the coolant inlet of the water-immersed energy storage battery box. The coolant inlet and coolant outlet are correspondingly located on opposite sides of the water-immersed energy storage battery box, with the coolant inlet higher than the coolant outlet to achieve partial immersion. Partial immersion enhances the battery's heat dissipation (heating) capacity, improves the battery's effective utilization efficiency, balances the temperature difference between battery cells, and enhances the fire resistance of the energy storage battery. Simultaneously, the use of the ultrapure water generator to prepare ultrapure water as a coolant significantly reduces the cost of the submersible energy storage system.

Description

Technical Field

[0001] This invention relates to the field of energy storage system technology, and specifically to a water-immersed energy storage battery box integrated system. Background Technology

[0002] Energy storage systems are a crucial component of modern power systems and smart grids, and a vital link in achieving effective grid integration of renewable energy and distributed generation. In recent years, with the continuous advancement of battery technology, electrochemical energy storage systems, primarily based on lithium batteries, have developed rapidly. Lithium-ion battery energy storage systems offer advantages such as high energy density, high conversion efficiency, low self-discharge rate, and long lifespan. However, the performance of lithium batteries is significantly affected by temperature; excessively high or low temperatures can impact battery performance and lifespan, and in severe cases, even lead to safety accidents. Therefore, efficient thermal management is essential in lithium-ion battery energy storage systems.

[0003] Currently, most energy storage battery boxes adopt a liquid-cooled plate structure, which offers improved cooling performance compared to air cooling. However, liquid-cooled plates can only cool one side of the battery, leading to uneven battery temperature and potential safety hazards over long-term operation. Immersion liquid cooling is gradually gaining attention, but it primarily uses oil or fluorinated liquids as the working fluid. These fluids have high viscosity, increasing power consumption, and their relatively high price also raises the overall cost of energy storage system integration, failing to achieve the goal of cost reduction and efficiency improvement. Summary of the Invention

[0004] The purpose of this invention is to overcome the shortcomings of the prior art and provide a low-cost, high-efficiency water-immersed energy storage battery box integrated system to ensure that the energy storage lithium battery operates within a suitable temperature range, improve the overall temperature uniformity of the energy storage battery system, optimize the internal flow channel structure of the energy storage battery box, facilitate the long-term stable and reliable operation of the energy storage system, reduce the cost of the energy storage system, achieve the goal of cost reduction and efficiency improvement under the same cooling method, enhance the safety of the energy storage system, and extend the service life of the energy storage system.

[0005] To achieve the above objectives, the technical solution of the present invention is as follows:

[0006] An integrated system for a water-immersed energy storage battery box is suitable for square batteries, wherein the positive and negative tabs of the square batteries are located on the same plane, and includes an immersed energy storage battery box, a heat exchanger, an ultrapure water preparation machine, and a liquid storage tank.

[0007] The coolant outlet of the water-immersed energy storage battery box is connected to the inlet of the storage tank, the outlet of the storage tank is connected to the inlet of the ultrapure water generator, the outlet of the ultrapure water generator is connected to the inlet of the heat exchanger, and the outlet of the heat exchanger is connected to the coolant inlet of the water-immersed energy storage battery box.

[0008] The coolant inlet and coolant outlet are respectively located on opposite sides of the submersible energy storage battery box, and the coolant inlet is higher than the coolant outlet to achieve partial immersion; the direction of the coolant inlet and coolant outlet is parallel to the line connecting the positive and negative tabs of the square battery in the submersible energy storage battery box, and the positive and negative tabs of the square battery are far away from the bottom of the submersible energy storage battery box.

[0009] Optionally, a self-priming circulating pump is also installed in the pipeline connecting the heat exchanger and the ultrapure water preparation machine.

[0010] Optionally, the water-immersed energy storage battery box includes a battery box shell, spacer baffles, and a DEAN-like flow channel; the battery box shell is used to place battery modules, which are composed of several square batteries; the DEAN-like flow channel is located at the bottom of the battery box shell and serves as a bottom support for the battery modules; the spacer baffles are provided with mounting holes that match the battery modules for fitting onto them; the perimeter of the spacer baffles is sealed to the inner wall of the battery box shell; the coolant inlet and coolant outlet are both located below the spacer baffles; an overflow port is also provided below the spacer baffles in the battery box shell, and the overflow port is connected to the liquid storage tank.

[0011] Optionally, the battery box housing also includes positive and negative electrode outlets and a battery pack acquisition harness outlet.

[0012] Optionally, fixing holes and lifting holes are provided on the outside of the battery box housing.

[0013] Optionally, the DEAN diversion channel and the spacer baffle are both made of flame-retardant and insulating materials.

[0014] Optionally, the ultrapure water preparation machine is used to prepare ultrapure water with a resistivity greater than 18.2 MΩ·cm.

[0015] Optionally, the spacer baffle is fastened to the internal support of the battery box shell and sealed with waterproof sealant.

[0016] Optionally, the immersion energy storage battery box integrated system also includes a container shell, and the immersion energy storage battery box, heat exchanger, ultrapure water preparation machine, liquid storage tank and circulating self-priming pump are all installed inside the container shell.

[0017] Optionally, the coolant outlet of the water-immersed energy storage battery box is connected to the inlet of the storage tank via a waterproof connector; the outlet of the heat exchanger is connected to the coolant inlet of the water-immersed energy storage battery box via a waterproof connector.

[0018] Compared with the prior art, the advantages of this invention are as follows:

[0019] This invention enhances the heat dissipation (heating) capacity of the battery through partial immersion, improves the effective utilization efficiency of the battery, balances the temperature difference between battery cells, and enhances the fire resistance of the energy storage battery. At the same time, by using an ultrapure water preparation machine to prepare ultrapure water as a coolant, the cost of the immersion energy storage system can be significantly reduced and the service life of the immersion energy storage system equipment can be extended while improving the heat exchange effect. In addition, since the direction of the coolant inlet and outlet is parallel to the line connecting the positive and negative tabs of the battery, the flow path is shortened and the temperature uniformity is improved. Attached Figure Description

[0020] Figure 1 A schematic diagram of the integrated system of the water-immersed energy storage battery box provided in the embodiments of this application;

[0021] Figure 2 This is a schematic diagram of the internal components of a water-immersed energy storage battery box.

[0022] Figure 3 A schematic diagram of a DEAN-like flow channel structure inside a water-immersed energy storage battery box;

[0023] Figure 4 A schematic diagram of the internal partitions and batteries of a water-immersed energy storage battery box;

[0024] Figure 5 A schematic diagram of the internal assembly of a water-immersed energy storage battery box;

[0025] Figure 6 A schematic diagram of the internal assembly of a water-immersed energy storage battery box;

[0026] Figure 7 This is a schematic diagram of the external components of a water-immersed energy storage battery box.

[0027] Figure 8 This is a schematic diagram of the inlet and outlet methods for a water-immersed energy storage battery box.

[0028] In the diagram: 1. Container shell; 2. Water-immersed energy storage battery box; 2-1. Battery box cover; 2-11. Positive and negative electrode outlets; 2-12. Fixing holes; 2-13. Lifting holes; 2-14. Battery pack acquisition harness outlet; 2-2. Spacer baffle; 2-21. Waterproof sealant; 2-3. Battery; 2-4. DEAN-like flow channel; 2-5. Battery box shell; 2-6. Coolant outlet; 2-7. Overflow port; 2-8. Internal support; 2-9. Coolant inlet; 3. Energy storage high-pressure box; 4. Heat exchanger inlet; 5. Heat exchanger; 6. Circulating self-priming pump; 7. Ultrapure water preparation machine; 8. Storage tank; 9. Storage tank outlet; 10. Battery bracket. Detailed Implementation

[0029] Example:

[0030] To make the above-mentioned objectives, features, and advantages of this application more apparent and understandable, the specific embodiments of this application are described in detail below with reference to the accompanying drawings. Many specific details are set forth in the following description to provide a thorough understanding of this application. However, this application can be implemented in many other ways different from those described herein, and those skilled in the art can make similar modifications without departing from the spirit of this application. Therefore, this application is not limited to the specific embodiments disclosed below.

[0031] In the description of this application, it should be understood that if the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", "axial", "radial", "circumferential", etc. appear, these terms indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, and are only for the convenience of describing this application and simplifying the description, and do not indicate or imply that the device or element 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.

[0032] Furthermore, where the terms "first" and "second" appear, these terms are for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include at least one of that feature. In the description of this application, where the term "multiple" appears, "multiple" means at least two, such as two, three, etc., unless otherwise explicitly specified.

[0033] In this application, unless otherwise expressly specified and limited, the terms "installation," "connection," "joining," and "fixing," etc., should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can be a mechanical connection or an electrical connection; they can be a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components, unless otherwise expressly limited. Those skilled in the art can understand the specific meaning of the above terms in this application according to the specific circumstances.

[0034] In this application, unless otherwise expressly specified and limited, the use of descriptions such as "above" or "below" the second feature indicates that the first and second features are in direct contact, or indirect contact via an intermediate medium. Furthermore, "above," "on top of," and "over" the second feature can mean that the first feature is directly above or diagonally above the second feature, or simply that the first feature is at a higher horizontal level than the second feature. Similarly, "below," "below," and "under" the second feature can mean that the first feature is directly below or diagonally below the second feature, or simply that the first feature is at a lower horizontal level than the second feature.

[0035] It should be noted that if an element is referred to as being "fixed to" or "set on" another element, it can be directly on the other element or there may be an intervening element. If an element is considered to be "connected to" another element, it can be directly connected to the other element or there may be an intervening element. If so, the terms "vertical," "horizontal," "upper," "lower," "left," "right," and similar expressions used in this application are for illustrative purposes only and do not represent the only possible implementation.

[0036] See Figure 1-8 As shown, the water-immersed energy storage battery box integrated system provided in this embodiment is suitable for prismatic batteries, wherein the positive and negative tabs of the prismatic battery are located on the same plane, and mainly includes a water-immersed energy storage battery box 2, a heat exchanger 5, an ultrapure water generator 7, and a liquid storage tank 8.

[0037] The water-immersed energy storage battery box 2, heat exchanger 5, ultrapure water generator 7, and storage tank 8 are sequentially connected to form the heat dissipation section. Specifically, the coolant outlet 2-6 of the water-immersed energy storage battery box 2 is connected to the inlet of the storage tank 8 via a waterproof connector. The outlet of the storage tank 8 is connected to the inlet of the ultrapure water generator 7. The outlet of the ultrapure water generator is connected to the inlet of the heat exchanger. The outlet of the heat exchanger is connected to the coolant inlet 2-9 of the water-immersed energy storage battery box via a waterproof connector. In this way, the ultrapure water prepared by the ultrapure water generator through multiple filtrations can be used as a cooling liquid to enter the water-immersed energy storage battery box. This reduces the cost of using the immersion liquid and, on the other hand, the high heat transfer performance of ultrapure water also makes it a good fire suppression medium, especially prominent in the control of lithium battery thermal runaway. While existing technologies disclose methods that involve immersing the coolant in a pump and deionizer, using a pump to drive the coolant into the deionizer to adsorb ions and improve its insulation, this requires extremely stringent sealing to prevent water contamination. Otherwise, deionization may not be achieved. Furthermore, the pump's own pressure makes it difficult to drive the coolant into the deionizer. In this application, however, the ultrapure water generator 7 is positioned between the heat exchanger 5 and the storage tank 8. The coolant is first stored in the storage tank 8, then filtered multiple times by the water generator before entering the heat exchanger 5 for cooling. This effectively solves the problem of needing to immerse both the pump and deionizer in the coolant.

[0038] The coolant inlet 2-9 and coolant outlet 2-6 are respectively located on opposite sides of the water-immersed energy storage battery box 2, with the coolant inlet 2-9 higher than the coolant outlet 2-6. In other words, the coolant inlet and outlet of the water-immersed energy storage battery box 2 is a side-mounted, top-inlet, bottom-outlet configuration, thus achieving partial immersion. Figure 8 As shown, the directions of the coolant inlet 2-9 and coolant outlet 2-6 are parallel to the lines connecting the positive and negative terminals of the batteries inside the submerged energy storage battery box. This shortens the coolant flow path and further improves the temperature uniformity of the battery modules. Simultaneously, because the coolant in the submerged energy storage battery box is partially submerged, it effectively improves the overall temperature uniformity within the battery box, reduces the amount of working fluid used, lowers the possibility of rising water vapor eroding the battery terminals, and effectively prevents short circuits. The ultrapure water exiting from coolant outlet 2-6 flows back to the storage tank. The ultrapure water generator 7 then filters the water in the storage tank again, cools it through heat exchanger 5, and then enters the submerged energy storage battery box 2, thus allowing for the recycling of cooling water. This ultrapure water generator can be placed in the equipment compartment of the energy storage system, depending on the water supply volume, or on the outside of the energy storage system, depending on the scale of the energy storage power station.

[0039] In a preferred embodiment, a self-priming circulating pump 6 is installed in the pipeline connecting the heat exchanger 5 and the ultrapure water generator 7 to ensure the circulation of the coolant. Furthermore, to ensure that the resistivity of the ultrapure water produced by the ultrapure water generator 7 is greater than 18.2 MΩ·cm, the ultrapure water produced by the ultrapure water generator 7 must be detected by a sensor. Only after passing the detection does it enter the self-priming circulating pump 6; if it fails the detection, it re-enters the ion water generator 7 for re-processing.

[0040] In one specific embodiment, the water-immersed energy storage battery box 2 includes a battery box cover 2-1, a battery box shell 2-5, a spacer baffle 2-2, and a DEAN-like shunt channel 2-4; the battery box shell 2-5 is used to house battery modules, which are composed of several square batteries 2-3 connected in series, with the positive and negative terminals of the batteries corresponding and far away from the bottom of the battery box shell 2-5, thus... Figure 4 As shown, this design ensures that the battery tabs are not corroded by high-temperature moisture, effectively preventing short circuits. It should be noted that the number of batteries inside the battery case (2-5) can be freely increased or decreased according to needs.

[0041] The DEAN-like flow channel 2-4 is located at the bottom of the battery box shell 2-5 and serves as a bottom support for the battery module. By placing the DEAN-like flow channel 2-4 at the bottom of the battery box shell 2-5, the uniformity of fluid distribution at the bottom is increased, and it also serves as a bottom support for the battery module, enhancing bottom fluidity. The spacer baffle 2-2 has mounting holes that match the battery module, allowing it to be fitted onto the battery module and enhancing the applicability of the immersion energy storage box. The spacer baffle 2-2 is sealed to the inner wall of the battery box shell 2-5, thus reducing the corrosion of battery tabs and electronic components in the data acquisition and communication section by rising moisture, which is beneficial for the safe, accurate, and stable transmission of data in the energy storage management system. The coolant inlet 2-9 and coolant outlet 2-6 are both located below the baffle 2-2. Below the baffle 2-2 and inside the battery box casing 2-5, there is also an overflow port 2-7. This helps to reduce the pressure of the water flow on the baffle 2-2 when the coolant flow rate is too fast, thus ensuring the stability of the total amount of submerged liquid. The overflow port 2-7 is connected to the storage tank 2, meaning that the water coming out of the overflow port 2-7 will also re-enter the storage tank 2, achieving recycling.

[0042] In one specific embodiment, the water-immersed energy storage battery box 2 further includes battery box positive and negative electrode outlets 2-11 and battery pack acquisition harness outlets 2-14 for electrical and communication connections. The positive and negative electrode outlets can be interchanged depending on the series connection configuration of the battery modules. The electrical and communication interfaces of the energy storage battery box can directly utilize existing battery modules without special modifications, which helps reduce battery module assembly costs. The bottom outer side of the water-immersed energy storage battery box 2 has fixing holes 2-12 for battery brackets and battery box shell lifting holes 2-13 used during energy storage system assembly. The fixing holes 2-12 and lifting holes 2-13 can be added or removed according to the weight of the energy storage battery box, but their applicability must be ensured, improving the overall system's transportation efficiency and assembly stability.

[0043] In one specific embodiment, both the DEAN diversion channel 2-4 and the spacer baffle 2-2 are made of flame-retardant and insulating materials. Both structures are detachable, which improves the flexibility of battery box assembly and enhances battery box safety.

[0044] In one specific embodiment, the ultrapure water 18.2 is fastened to the internal support 2-8 of the battery box shell 2-5 and sealed with waterproof sealant 2-21.

[0045] Furthermore, the aforementioned submerged energy storage battery box integrated system also includes a container shell 1, an energy storage high-voltage box 3, and a battery bracket 10. The battery bracket 10 stacks several submerged energy storage battery boxes 2, with the coolant outlet of each submerged energy storage battery box 2 individually connected to a heat exchanger. The energy storage high-voltage box serves as an electrical isolation between the PCS and the batteries. The submerged energy storage battery boxes 2, heat exchanger 5, ultrapure water generator 7, energy storage high-voltage box 3, battery bracket 10, liquid storage tank 9, and circulating self-priming pump 6 are all housed within the container shell. Additionally, a complete energy storage system should also include common supporting structures for lithium battery energy storage systems, such as a battery management system, energy storage controller, fire alarm system, and chiller. These can be placed in other spaces within the energy storage container. For ease of practical design and application, these will not be elaborated upon here and will be determined based on actual application conditions.

[0046] The above embodiments are merely illustrative of the technical concept and features of the present invention, and are intended to enable those skilled in the art to understand the content of the present invention and implement it accordingly. They should not be construed as limiting the scope of protection of the present invention. All equivalent changes or modifications made based on the essence of the content of the present invention should be covered within the scope of protection of the present invention.

Claims

1. A water-immersed energy storage battery box integrated system, suitable for prismatic batteries, wherein the positive and negative tabs of the prismatic battery are located on the same plane, characterized in that, This includes submersible energy storage battery boxes, heat exchangers, ultrapure water preparation machines, and liquid storage tanks; The coolant outlet of the water-immersed energy storage battery box is connected to the inlet of the storage tank, the outlet of the storage tank is connected to the inlet of the ultrapure water generator, the outlet of the ultrapure water generator is connected to the inlet of the heat exchanger, and the outlet of the heat exchanger is connected to the coolant inlet of the water-immersed energy storage battery box. The coolant inlet and coolant outlet are respectively located on opposite sides of the submersible energy storage battery box, with the coolant inlet higher than the coolant outlet to achieve partial immersion; the direction of the coolant inlet and coolant outlet is parallel to the line connecting the positive and negative tabs of the square battery inside the submersible energy storage battery box; the positive and negative tabs of the square battery are far away from the bottom of the submersible energy storage battery box. The water-immersed energy storage battery box includes a battery box shell, spacer baffles, and a DEAN-like shunt channel. The battery box shell is used to house battery modules, which are composed of several square batteries. The DEAN-like shunt channel is located at the bottom of the battery box shell and serves as a bottom support for the battery modules. The spacer baffles have mounting holes that match the battery modules for mounting, with positive and negative tabs located above the spacer baffles. The spacer baffles are sealed to the inner wall of the battery box shell. The coolant inlet and coolant outlet are both located below the spacer baffles. An overflow port is also provided below the spacer baffles and inside the battery box shell, and the overflow port is connected to the storage tank. The spacer baffle is fastened to the internal support of the battery box shell and sealed with waterproof sealant.

2. The immersion energy storage battery box integrated system as described in claim 1, characterized in that, A self-priming circulating pump is also installed in the pipeline connecting the heat exchanger and the ultrapure water preparation machine.

3. The immersion energy storage battery box integrated system as described in claim 1, characterized in that, The battery box casing also includes positive and negative electrode outlets and a battery pack acquisition harness outlet.

4. The immersion energy storage battery box integrated system as described in claim 1 or 3, characterized in that, Fixing holes and lifting holes are provided on the outside of the battery box casing.

5. The immersion energy storage battery box integrated system as described in claim 1, characterized in that, The DEAN diversion channel and the partition baffle are both made of flame-retardant and insulating materials.

6. The immersion energy storage battery box integrated system as described in claim 1, characterized in that, The ultrapure water preparation machine is used to prepare ultrapure water with a resistivity greater than 18.2 MΩ·cm.

7. The immersion energy storage battery box integrated system as described in claim 2, characterized in that, It also includes the container shell, and the submersible energy storage battery box, heat exchanger, ultrapure water preparation machine, liquid storage tank and circulating self-priming pump are all installed inside the container shell.

8. The immersion energy storage battery box integrated system as described in claim 1, characterized in that, The coolant outlet of the water-immersed energy storage battery box is connected to the inlet of the storage tank via a waterproof connector; the outlet of the heat exchanger is connected to the coolant inlet of the water-immersed energy storage battery box via a waterproof connector.

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