Water-immersed energy storage battery box integrated system

Abstract

The invention discloses a water immersion type energy storage battery box integrated system which comprises an immersion type energy storage battery box, a heat exchanger, an ultrapure water preparation machine and a liquid storage tank, a cooling liquid outlet of the water immersion type energy storage battery box is connected with an inlet of the liquid storage tank, an outlet of the liquid storage tank is connected with an inlet of the ultrapure water preparation machine, an outlet of the ultrapure water preparation machine is connected with an inlet of the heat exchanger, and an outlet of the heat exchanger is connected with a cooling liquid inlet of the water immersion type energy storage battery box; the cooling liquid inlet and the cooling liquid outlet are correspondingly formed in the two opposite sides of the water-immersed energy storage battery box, and the cooling liquid inlet is higher than the cooling liquid outlet so that local immersion can be achieved. Through a local immersion mode, the heat dissipation (heating) capability of the battery can be enhanced, the effective utilization efficiency of the battery is improved, the temperature difference between the battery monomers is balanced, the fire-fighting property of the energy storage battery is enhanced, and meanwhile, the ultrapure water preparation machine is used for preparing ultrapure water as cooling liquid, so that the cost of the immersed energy storage system is greatly reduced.

Description

Technical Field

[0001] The present invention relates to the technical field of energy storage systems, and in particular to a water-immersed energy storage battery box integrated system. Background Art

[0002] Energy storage systems are an important part of modern power systems and smart grids, and are also an important part of achieving effective grid connection of renewable energy and distributed power generation. In recent years, with the continuous advancement of battery technology, electrochemical energy storage systems based on lithium batteries have developed rapidly. Lithium-ion energy storage systems have the advantages of high energy density, high conversion efficiency, low self-discharge rate, and long service life. However, the performance of lithium batteries is greatly affected by temperature. Too high or too low temperatures may affect the performance and service life of the battery, and even lead to safety accidents in severe cases. Therefore, it is necessary to perform efficient thermal management in lithium-ion energy storage systems.

[0003] At present, most energy storage battery boxes adopt liquid cooling plate structure. Compared with air cooling, the cooling performance is improved to a certain extent, but the liquid cooling plate can only cool one side of the battery, resulting in uneven temperature of the battery body, which is prone to safety hazards in long-term operation. At this time, immersion liquid cooling gradually came into people's view, but the working fluid used in immersion liquid cooling is mainly oil or fluorinated liquid, which has a large working fluid viscosity and correspondingly increases power consumption. At the same time, the working fluid price is relatively high, which also virtually increases the integration cost of the energy storage system and cannot achieve the purpose of reducing costs and increasing efficiency. . Summary of the invention

[0004] The purpose of the present invention is to overcome the deficiencies of the above-mentioned 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 in a suitable temperature range, improve the uniformity of the overall temperature of the energy storage battery system, optimize the internal flow channel structure of the energy storage battery box, which is conducive to the long-term stable and reliable operation of the energy storage system, reduces the cost of the energy storage system, and achieves the purpose of reducing costs and increasing efficiency under the same cooling method, enhances the safety of the energy storage system, and extends the service life of the energy storage system.

[0005] To achieve the above object, the technical solution of the present invention is:

[0006] A water-immersed energy storage battery box integrated system, suitable for square batteries, wherein the positive and negative tabs of the square batteries are located in the same plane, comprising 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 liquid storage tank, the outlet of the liquid storage tank is connected to the inlet of the ultrapure water preparation machine, the outlet of the ultrapure water preparation machine 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 the coolant outlet are correspondingly arranged on opposite sides of the water-immersed energy storage battery box, and the coolant inlet is higher than the coolant outlet to achieve partial immersion; the directions of the coolant inlet and the coolant outlet are parallel to the connecting lines of the positive and negative tabs of the square batteries in the immersion energy storage battery box, and the positive and negative tabs of the square batteries are away from the bottom of the immersion energy storage battery box.

[0009] Optionally, a circulating self-priming 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, a spacer baffle and a DEAN-like shunt flow channel; the battery box shell is used to place a battery module, and the battery module is composed of a number of the square batteries; the DEAN-like shunt flow channel is arranged at the bottom of the battery box shell and serves as the bottom support of the battery module; the spacer baffle is distributed with mounting holes matching the battery module so as to be sleeved on the battery module; the spacer baffle is sealed and connected to the inner wall of the battery box shell on all sides; the coolant inlet and the coolant outlet are both arranged below the spacer baffle; an overflow port is also arranged below the spacer baffle and in the battery box shell, and the overflow port is connected to the liquid storage tank.

[0011] Optionally, the battery box housing is also provided with positive and negative terminal lug outlets for the battery box and a battery pack wiring harness outlet.

[0012] Optionally, fixing holes and lifting holes are provided on the outer side of the battery box shell.

[0013] Optionally, the DEAN diversion channel and the spacing 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 and assembled with a waterproof sealant.

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

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

[0018] Compared with the prior art, the present invention has the following beneficial effects:

[0019] The present invention can enhance the heat dissipation (heating) capacity of the battery through partial immersion, improve the effective utilization efficiency of the battery, balance the temperature difference between battery cells, and enhance the fire-fighting properties of the energy storage battery. At the same time, ultrapure water is prepared by an ultrapure water preparation machine as a coolant, which can greatly reduce the cost of the immersion energy storage system while enhancing the heat exchange effect and extend the service life of the immersion energy storage system equipment. At the same time, since the inlet and outlet directions of the coolant are parallel to the connection lines of the positive and negative ears of the battery, the flow path is shortened and the temperature consistency is improved. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Figure 1 A schematic diagram of the composition of the water-immersed energy storage battery box integrated system provided in an embodiment of the present application;

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

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

[0023] Figure 4 This is a schematic diagram of the internal partition baffle and battery of the water-immersed energy storage battery box;

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

[0025] Figure 6 This is 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 Schematic diagram of the import and export methods of the water-immersed energy storage battery box.

[0028] In the figure: 1. Container shell; 2. Water-immersed energy storage battery box; 2-1. Battery box cover; 2-11. Positive and negative ear outlet; 2-12. Fixing hole; 2-13. Lifting hole; 2-14. Battery pack collection harness outlet; 2-2. Spacer baffle; 2-21. Waterproof sealant; 2-3. Battery; 2-4. DEAN-like shunt 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. Liquid storage tank; 9. Liquid storage tank outlet; 10. Battery bracket. DETAILED DESCRIPTION

[0029] Example:

[0030] In order to make the above-mentioned purposes, features and advantages of the present application more obvious and easy to understand, the specific implementation methods of the present application are described in detail below in conjunction with the accompanying drawings. In the following description, many specific details are set forth to facilitate a full understanding of the present application. However, the present application can be implemented in many other ways different from those described herein, and those skilled in the art can make similar improvements without violating the connotation of the present application, so the present application is not limited by the specific embodiments disclosed below.

[0031] In the description of the present application, it should be understood that if the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", "clockwise", "counterclockwise", "axial", "radial", "circumferential", etc. appear, the orientation or position relationship indicated by these terms is based on the orientation or position relationship shown in the drawings, which is only for the convenience of describing the present application and simplifying the description, and does not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the present application.

[0032] In addition, if the terms "first" or "second" appear, these terms are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Therefore, the features defined as "first" or "second" may explicitly or implicitly include at least one of the features. In the description of this application, if the term "plurality" appears, "plurality" means at least two, such as two, three, etc., unless otherwise clearly and specifically defined.

[0033] In this application, unless otherwise clearly specified and limited, if the terms "install", "connect", "connect", "fix" and the like appear, these terms should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or an integral one; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium; it can be the internal connection of two elements or the interaction relationship between two elements, unless otherwise clearly defined. For ordinary technicians in this field, the above terms can be understood in their specific meanings in this application according to the specific circumstances.

[0034] In this application, unless otherwise clearly specified and limited, if there is a description such as "above" or "below" a second feature, it may mean that the first and second features are in direct contact, or that the first and second features are in indirect contact through an intermediate medium. Moreover, "above", "above" and "above" a first feature may mean that the first feature is directly above or obliquely above the second feature, or simply means that the first feature is higher in level than the second feature. "Below", "below" and "below" a first feature may mean that the first feature is directly below or obliquely below the second feature, or simply means that the first feature is lower in level than the second feature.

[0035] It should be noted that if an element is referred to as being "fixed to" or "disposed on" another element, it may be directly on the other element or there may be a central element. If an element is considered to be "connected to" another element, it may be directly connected to the other element or there may be a central element at the same time. If any, 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 implementation method.

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

[0037] The water-immersed energy storage battery box 2, the heat exchanger 5, the ultrapure water preparation machine 7 and the liquid storage tank 8 are connected in sequence to form a heat dissipation part. Specifically, the coolant outlet 2-6 of the water-immersed energy storage battery box 2 is connected to the inlet of the liquid storage tank 8 through a waterproof joint, the outlet of the liquid storage tank 8 is connected to the inlet of the ultrapure water preparation machine 7, the outlet of the ultrapure water preparation machine is connected to the inlet of the heat exchanger, and the outlet of the heat exchanger is connected to the coolant inlet 2-9 of the water-immersed energy storage battery box through a waterproof joint. In this way, the ultrapure water prepared by multiple filtrations of the ultrapure water preparation machine can be used as a cooling liquid to enter the water-immersed energy storage battery box. On the one hand, it reduces the use cost of the immersion liquid, and on the other hand, the ultrapure water has efficient heat transfer performance and is also a good fire-fighting medium, especially for the thermal runaway control of lithium batteries. Although the prior art discloses immersing a water pump and a deionizer in the coolant, and driving the coolant into the deionizer through the water pump, so as to utilize the deionizer to absorb the ions in the coolant and increase the insulation performance of the coolant, since both the water pump and the deionizer are immersed in the coolant, extremely strict sealing is required to achieve the goal of not polluting the water source itself, otherwise it may lead to failure to achieve the purpose of deionization, and since the water pump is immersed in the coolant, under the pressure of the liquid itself, it is difficult for the water pump to drive the coolant into the deionizer. In the scheme of the present application, by arranging the ultrapure water preparation machine 7 between the heat exchanger 5 and the liquid storage tank 8, the coolant is first stored in the liquid storage tank 8, and then enters the heat exchanger 5 for cooling after being filtered multiple times by the ion water preparation machine, thereby effectively solving the problem of needing to immerse both the water pump and the deionizer in the coolant.

[0038] The coolant inlet 2-9 and the coolant outlet 2-6 are correspondingly arranged on opposite sides of the water-immersed energy storage battery box 2, and the coolant inlet 2-9 is higher than the coolant outlet 2-6. That is to say, the coolant inlet and outlet of the water-immersed energy storage battery box 2 are inlet from the top and outlet from the bottom, thereby realizing partial immersion. Figure 8 As shown, the directions of the coolant inlet 2-9 and the coolant outlet 2-6 are parallel to the connection lines of the positive and negative tabs of the battery in the submerged energy storage battery box. This shortens the coolant flow path and further improves the temperature consistency of the battery module. At the same time, since the water-immersed energy storage battery box coolant adopts a local immersion method, it can effectively improve the overall temperature uniformity in the battery box, while reducing the amount of working fluid used, reducing the possibility of rising water vapor eroding the battery tab part, and effectively preventing the occurrence of short circuits. The ultrapure water coming out of the coolant outlet 2-6 flows back to the liquid storage tank, and the ultrapure water preparation machine 7 filters the water in the liquid storage tank again, and then enters the water-immersed energy storage battery box 2 ultrapure water after cooling through the heat exchanger 5, so that the cooling water can be recycled. The ultrapure water preparation machine can be placed in the equipment compartment of the energy storage system according to the amount of water supply, or placed on the outside of the energy storage system according to the scale of the energy storage power station.

[0039] In a preferred embodiment, a circulating self-priming pump 6 is also installed in the pipeline connecting the heat exchanger 5 and the ultrapure water preparation machine 7 to ensure the flow and circulation of the coolant. In addition, in order to ensure that the resistivity of the ultrapure water prepared by the ultrapure water preparation machine 7 is greater than 18.2MΩ·cm, the ultrapure water prepared by the ultrapure water preparation machine 7 needs to be tested by a sensor, and only after passing the test can it enter the circulating self-priming pump 6. If the test fails, it will re-enter the ion water preparation machine 7 for re-preparation.

[0040] In a 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 flow channel 2-4; the battery box shell 2-5 is used to place a battery module, which is composed of a number of square batteries 2-3 connected in series, and the positive and negative poles of the battery correspond to each other and are far away from the bottom of the battery box shell 2-5. Figure 4 As shown, this can ensure that the battery tabs are not corroded by high-temperature water vapor, effectively preventing the occurrence of short circuits. It should be noted that the number of batteries in the battery box housing 2-5 can be freely increased or decreased according to demand.

[0041] The DEAN-like shunt flow channel 2-4 is arranged at the bottom of the battery box shell 2-5 and serves as the bottom support of the battery module; thus, by placing the DEAN-like shunt flow channel 2-4 at the bottom 2-5 of the battery box shell, the uniformity of the bottom fluid distribution is increased on the one hand, and on the other hand, it can serve as the bottom support of the battery module to increase the bottom fluidity of the battery. The spacer baffle 2-2 is provided with mounting holes matching the battery module so as to be sleeved on the battery module to enhance the applicability of the submerged energy storage box; the four sides of the spacer baffle 2-2 are sealed and connected to the inner wall of the battery box shell 2-5, so that the erosion of the rising water vapor on the battery pole ears and the electronic components of the data acquisition and communication part can be reduced, which is conducive to the safe, accurate and stable transmission of the data of the energy storage management system. The coolant inlet 2-9 and the coolant outlet 2-6 are both arranged below the spacer baffle 2-2; an overflow port 2-7 is also arranged below the spacer baffle 2-2 and in the battery box shell 2-5, which can help the battery module to reduce the pressure of the water flow on the spacer baffle 2-2 when the coolant flow rate is too fast, thereby ensuring the stability of the total amount of immersion liquid. The overflow port 2-7 is connected to the liquid storage tank 2, that is, the water coming out of the overflow port 2-7 will enter the liquid storage tank 2 again to achieve recycling.

[0042] In a specific embodiment, the water-immersed energy storage battery box 2 also includes a battery box positive and negative terminal ear outlet 2-11 and a battery pack collection harness outlet 2-14 for electrical and communication connections, and the positive and negative terminal outlets can be interchanged according to the series connection form of the battery module. The electrical and communication interfaces of the energy storage battery box can directly adopt the existing battery module without the need for special modification, which is beneficial to reduce the assembly cost of the battery module. The outer bottom of the water-immersed energy storage battery box 2 has a fixing hole 2-12 for the battery bracket and a battery box shell hoisting hole 2-13 used when assembling the energy storage system. The fixing hole 2-12 and the hoisting hole 2-13 can be increased or decreased according to the weight of the energy storage battery box, but their applicability must be guaranteed, which improves the transportation efficiency and assembly stability of the entire system.

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

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

[0045] In addition, the 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 up several water-submerged energy storage battery boxes 2, and the coolant outlet of each water-submerged energy storage battery box 2 is individually connected to the heat exchanger. The energy storage high-voltage box serves as an electrical partition between the PCS and the battery. The submerged energy storage battery box 2, the heat exchanger 5, the ultrapure water preparation machine 7, the energy storage high-voltage box 3, the battery bracket 10, the liquid storage tank 9 and the circulating self-priming pump 6 are all arranged in the container shell. In addition, the complete energy storage system should also include a battery management system, an energy storage controller, a battery management system, a fire alarm system, a chiller and other common supporting structures of lithium battery energy storage systems. These can be placed in other spaces of the energy storage container. In order to facilitate the actual design and application of the system, it will not be elaborated in detail here, and it will be determined according to the actual application situation.

[0046] The above embodiments are only for illustrating the technical concept and features of the present invention, and their purpose is to enable ordinary technicians in the field to understand the content of the present invention and implement it accordingly, and they cannot be used to limit the protection scope of the present invention. Any equivalent changes or modifications made based on the essence of the content of the present invention should be included in the protection scope of the present invention.

Claims

1. A water-immersed energy storage battery box integrated system, suitable for square batteries, the positive and negative terminals of the square batteries are located in the same plane, characterized in that: Including immersion energy storage battery box, heat exchanger, ultrapure water preparation machine and liquid storage tank; The coolant outlet of the water-immersed energy storage battery box is connected to the inlet of the liquid storage tank, the outlet of the liquid storage tank is connected to the inlet of the ultrapure water preparation machine, the outlet of the ultrapure water preparation machine 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 the coolant outlet are correspondingly arranged on opposite sides of the water-immersed energy storage battery box, and the coolant inlet is higher than the coolant outlet to achieve partial immersion; the directions of the coolant inlet and the coolant outlet are parallel to the connecting lines of the positive and negative tabs of the square batteries in the immersion energy storage battery box; the positive and negative tabs of the square batteries are away from the bottom of the immersion energy storage battery box.

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

3. The submerged energy storage battery box integrated system according to claim 1, characterized in that: The water-immersed energy storage battery box includes a battery box shell, a spacer baffle and a DEAN-like shunt flow channel; the battery box shell is used to place a battery module, and the battery module is composed of a number of square batteries; the DEAN-like shunt flow channel is arranged at the bottom of the battery box shell and serves as the bottom support of the battery module; the spacer baffle is distributed with mounting holes matching the battery module so as to be sleeved on the battery module; the four sides of the spacer baffle are sealed and connected to the inner wall of the battery box shell; the coolant inlet and the coolant outlet are both arranged below the spacer baffle; an overflow port is also arranged below the spacer baffle and in the battery box shell, and the overflow port is connected to the liquid storage tank.

4. The submerged energy storage battery box integrated system according to claim 1, characterized in that: The battery box housing is also provided with positive and negative terminal lug outlets of the battery box and a battery pack collection harness outlet.

5. The submerged energy storage battery box integrated system according to claim 1 or 4, characterized in that: A fixing hole and a lifting hole are arranged on the outer side of the battery box shell.

6. The submerged energy storage battery box integrated system according to claim 3, characterized in that: The DEAN flow diversion channel and the spacing baffle are both made of flame-retardant and insulating materials.

7. The submerged energy storage battery box integrated system according to 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.

8. The submerged energy storage battery box integrated system according to claim 6, characterized in that: The spacer baffle is fastened to the internal support of the battery box shell and is sealed and assembled with a waterproof sealant.

9. The submerged energy storage battery box integrated system according to claim 2, characterized in that: It also includes a container shell, in which the submerged energy storage battery box, the heat exchanger, the ultrapure water preparation machine, the liquid storage tank and the circulating self-priming pump are all arranged.

10. The submerged energy storage battery box integrated system according to claim 3, characterized in that: The coolant outlet of the water-immersed energy storage battery box is connected to the inlet of the liquid storage tank through a waterproof joint; the outlet of the heat exchanger is connected to the coolant inlet of the water-immersed energy storage battery box through a waterproof joint.

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