All-vanadium redox flow battery system with laminated structure

Abstract

The utility model belongs to the technical field of all-vanadium redox flow batteries, and discloses an all-vanadium redox flow battery system with a laminated structure. Comprising a power container, a capacity container, a refrigerating machine, a frequency conversion box and a confluence direct current box, an electric pile is located in the power container, an electrolyte storage tank and a circulating pump are located in the capacity container, the power container, the refrigerating machine and the frequency conversion box are installed and fixed above the capacity container, and the power container is connected with the capacity container through a pipeline. A confluence direct current box is arranged on the side face of the capacity container and connected with the power container through a cable. One set of battery module can comprise a plurality of capacity containers, so that the integration level of the battery module is improved, the power and capacity of a single battery module are improved, the cost of auxiliary equipment is reduced, and the application of a large-scale energy storage power station is facilitated.

Description

Technical Field

[0001] The utility model belongs to the technical field of all-vanadium liquid flow batteries, and in particular relates to an all-vanadium liquid flow battery system with a laminated structure. Background Art

[0002] All-vanadium liquid flow battery has the characteristics of long service life, high safety performance and fast response speed, which is very suitable for the needs of large-scale energy storage. In the all-vanadium liquid flow battery system, the electrolyte is stored in the positive and negative electrode storage tanks respectively, and the electrolyte circulates in the battery stack and the electrolyte storage tank through the circulation pump and connecting pipes.

[0003] The current common system structure is to horizontally integrate the power unit containing the battery stack and the capacity unit containing the storage tank in a container to achieve system modularization.

[0004] Compared with the most commonly used lithium-ion batteries, all-vanadium flow batteries have lower power density and energy density, so battery systems of the same size occupy a larger area. When the battery stack and the storage tank are at the same level, after shutdown, the amount of electrolyte in the battery stack will be continuously lost due to ion diffusion on both sides of the membrane and leakage current in the pipeline, affecting the operating efficiency of the battery. In addition, when the power part pipelines and equipment leak, all the residual liquid above the leakage will leak out, increasing the difficulty of preventing the system from leaking. The coils between the battery stacks to prevent leakage are generally installed near the battery stacks, which will take up a lot of space. Due to limited space, a large number of elbows are required to ensure the necessary length of the coils. The elbows will increase the flow resistance of the electrolyte, increase pump consumption, and reduce the efficiency of the battery system. Common flow battery storage tanks are cylindrical tanks. When installed in outdoor containers for use, the space utilization rate is low, while square welded tanks have a high risk of leakage. Due to the size of the container transportation, the capacity of each battery system is limited, that is, the scale of the single battery system is limited by the size of the container. Utility Model Content

[0005] In order to overcome the shortcomings of the prior art, the utility model provides an all-vanadium liquid flow battery system with a laminated structure, which eliminates the coil originally installed near the battery stack, reduces the number of elbows on the electrolyte circulation route, reduces flow resistance, that is, reduces pump consumption, improves system operation efficiency, and at the same time reduces the amount of piping materials used, and reduces the volume and design difficulty of the power part.

[0006] The above-mentioned purpose of the utility model is achieved through the following technical solutions: a laminated all-vanadium liquid flow battery system, including a power container, a capacity container, a refrigerator, a frequency converter, and a DC bus box. The battery stack is located in the power container, and the electrolyte storage tank and the circulation pump are located in the capacity container. The power container, the refrigerator, and the frequency converter are installed and fixed above the capacity container. The power container is connected to the capacity container through a pipeline. A DC bus box is provided on the side of the capacity container. The DC bus box is connected to the power container through a pipeline. A BMS is provided on the capacity container, and a DC box is provided on the power container.

[0007] Furthermore, the power container specifically includes a battery stack, an SOC, an HCL sensor, a smoke sensor, a leakage groove, a heater, and a pressure sensor. There are multiple battery stacks, each of which is equipped with a pressure sensor. A leakage groove is provided at the bottom of the battery stack, and the battery stack is connected to the SOC. An HCL sensor and a smoke sensor are installed on the top of the power container, and multiple heaters are provided on the lower side of the power container.

[0008] Further, the capacity container specifically includes a positive electrode storage tank, a negative electrode storage tank, a positive electrode liquid inlet pipe bundle, a positive electrode liquid return pipe bundle, a positive electrode secondary storage tank, a positive electrode heat exchanger, a positive electrode filter, a positive electrode pump, a positive electrode leakage sensor, a positive electrode temperature sensor, a heater, a negative electrode liquid inlet pipe bundle, a negative electrode liquid return pipe bundle, a negative electrode secondary storage tank, a negative electrode filter, a negative electrode pump, and a negative electrode leakage sensor. The positive electrode storage tank is connected to a positive electrode liquid inlet pipe bundle and a positive electrode liquid return pipe bundle. The positive electrode liquid return pipe bundle is provided with a positive electrode heat exchanger, a positive electrode filter, and a positive electrode temperature sensor from top to bottom. , a positive electrode pump, a positive electrode secondary storage tank is installed outside the positive electrode storage tank, a positive electrode leakage sensor is installed in the bottom space between the positive electrode secondary storage tank and the positive electrode storage tank, and a heater is installed at the bottom of the positive electrode secondary storage tank; the negative electrode storage tank is connected to a negative electrode liquid inlet pipe bundle and a negative electrode liquid return pipe bundle, and a negative electrode heat exchanger, a negative electrode filter, a negative electrode temperature sensor, and a negative electrode pump are arranged on the negative electrode return pipe bundle from top to bottom, a negative electrode secondary storage tank is installed outside the negative electrode storage tank, a negative electrode leakage sensor is installed in the bottom space between the negative electrode secondary storage tank and the negative electrode storage tank, and a heater is installed at the bottom of the negative electrode secondary storage tank.

[0009] Furthermore, there are multiple capacity containers and only one power container.

[0010] Furthermore, the upper edges of the positive electrode secondary storage tank and the negative electrode secondary storage tank are higher than the liquid level in the storage tanks.

[0011] Furthermore, the material of the leakage tank includes but is not limited to PP, PE, PVC, PVDF, PTFE, TPO, rubber, and metal with an anti-corrosion coating.

[0012] Furthermore, there are multiple positive electrode leakage sensors and multiple negative electrode leakage sensors.

[0013] Furthermore, the number of the positive electrode heat exchanger and the negative electrode heat exchanger is 0 or 1.

[0014] The beneficial effects of the utility model compared with the prior art are:

[0015] 1. The height of the power unit is higher than that of the capacity unit. When the liquid flow battery system is shut down, the electrolyte inside the power unit can quickly flow back to the capacity unit, solving the problem of electrolyte power loss in the shutdown state and effectively improving the energy efficiency of the liquid flow battery system. When the battery stack leaks, the leakage alarm in the leakage collection tank under the battery stack will detect the leakage fault, and the BMS control system will shut down. After the shutdown, all the electrolyte will flow back to the storage tank, minimizing the scale of the leakage accident.

[0016] 2. The stacked system structure in which the power unit is placed above the capacity unit is compared to the flat-layer structure. At the same time, the use of square roto-molded storage tanks in the capacity container improves space utilization and greatly saves space.

[0017] 3. A set of battery modules can contain multiple capacity containers, which improves the integration of battery modules, increases the power and capacity of single battery modules, reduces the cost of auxiliary equipment, and is more suitable for large-scale energy storage power station applications.

[0018] 4. The power unit is placed on the stacked system structure above the capacity unit. The container cover of the capacity unit can be used as an operating platform for daily maintenance of the power unit. The operating space is larger without taking up more space, which is convenient for maintenance;

[0019] 5. Since the branch pipeline from the pump outlet to the stack interface simultaneously serves the function of connecting the pump / heat exchanger and the stack to transport electrolyte and the anti-leakage coil, the coil originally installed near the stack is cancelled, the number of elbows on the electrolyte circulation route is reduced, the flow resistance is reduced, that is, the pump consumption is reduced, the system operation efficiency is improved, and the amount of pipeline materials is reduced, and the volume and design difficulty of the power part are reduced. This part of the pipeline can use a hose, which is more convenient for construction and on-site connection.

[0020] 6. Tank leakage collection tank can ensure that when a tank or its upper equipment pipeline leaks, all leaks can be collected to prevent the leaked liquid from entering the container and corroding the box material before leaking to the outside of the battery module

[0021] Multiple storage tanks with the same polarity share one circulation pump to ensure the uniformity of the electrolyte in the battery stack, reduce the difficulty of controlling the circulation system, and reduce the number of equipment. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] The present invention will be further described below in conjunction with the accompanying drawings and specific implementations.

[0023] Figure 1This is a cross-sectional view of the all-vanadium liquid flow battery system of the utility model with a laminated structure;

[0024] Figure 2 This is a side view of the all-vanadium liquid flow battery system of the utility model with a laminated structure;

[0025] Figure 3 This is the front view of the all-vanadium liquid flow battery system of the utility model with a laminated structure;

[0026] Figure 4 This is a top view of the all-vanadium liquid flow battery system with a laminated structure of the utility model.

[0027] In the figure, 1. power container; 2. capacity container; 3. refrigerator; 4. frequency converter; 5. converging DC box; 6. battery stack; 7. leakage tank; 8. heater; 9. pressure sensor; 10. HCL sensor; 11. SOC; 12. smoke sensor; 13. positive electrode inlet pipe bundle; 14. positive electrode return pipe bundle; 15. positive electrode secondary storage tank; 16. positive electrode heat exchanger; 17. positive electrode filter; 18. positive electrode pump; 19. positive electrode leakage sensor; 20. positive electrode temperature sensor; 21. negative electrode leakage sensor; 22. negative electrode pump; 23. negative electrode filter; 24. negative electrode secondary storage tank; 25. negative electrode return pipe bundle; 26. negative electrode inlet pipe bundle; 27. BMS; 28. DC box; 29. ​​positive electrode storage tank; 30. negative electrode storage tank; 31. negative electrode heat exchanger; 32. negative electrode temperature sensor; DETAILED DESCRIPTION

[0028] The present invention is described in detail below through specific examples, but the protection scope of the present invention is not limited. Unless otherwise specified, the experimental methods used in the present invention are all conventional methods, and the experimental equipment, materials, reagents, etc. used can be obtained from commercial channels.

[0029] Example 1

[0030] A laminated all-vanadium liquid flow battery system comprises a power container 1, a capacity container 2, a refrigerator 3, a frequency converter 4, and a DC bus box 5. A battery stack 6 is located in the power container 1, an electrolyte storage tank and a circulation pump are located in the capacity container 2, the power container 1, the refrigerator 3, and the frequency converter 4 are installed and fixed above the capacity container 2, the power container 1 is connected to the capacity container 2 through a pipeline, a DC bus box 5 is provided on the side of the capacity container 2, and the DC bus box 5 is connected to the power container 1 through a pipeline, a BMS 27 is provided on the capacity container 2, and a DC box 28 is provided on the power container 1.

[0031] The power container 1 specifically includes a battery stack 6, a SOC 11, an HCL sensor 10, a smoke sensor 12, a leakage tank 7, a heater 8, and a pressure sensor 9. The battery stack 6 is provided with multiple, each battery stack 6 is equipped with a pressure sensor 9, a leakage tank 7 is provided at the bottom of the battery stack 6, the battery stack 6 is connected to the SOC 11, an HCL sensor 10 and a smoke sensor 12 are installed on the top of the power container 1, and multiple heaters 8 are provided on the lower side of the power container 1.

[0032] The capacity container 2 specifically includes a positive electrode storage tank 29, a negative electrode storage tank 30, a positive electrode liquid inlet pipe bundle 13, a positive electrode liquid return pipe bundle 14, a positive electrode secondary storage tank 15, a positive electrode heat exchanger 16, a positive electrode filter 17, a positive electrode pump 18, a positive electrode leakage sensor 19, a positive electrode temperature sensor 20, a heater 8, a negative electrode liquid inlet pipe bundle 26, a negative electrode liquid return pipe bundle 25, a negative electrode secondary storage tank 24, a negative electrode filter 23, a negative electrode pump 22, and a negative electrode leakage sensor 21. The positive electrode storage tank 29 is connected to the positive electrode liquid inlet pipe bundle 13 and the positive electrode liquid return pipe bundle 14. The positive electrode liquid return pipe bundle 14 is provided with a positive electrode heat exchanger 16, a positive electrode filter 17, a positive electrode temperature sensor 20 in sequence from top to bottom. , a positive electrode pump 18, a positive electrode secondary storage tank 15 is installed outside the positive electrode storage tank 29, a positive electrode leakage sensor 19 is installed in the bottom space between the positive electrode secondary storage tank 15 and the positive electrode storage tank 29, and a heater 8 is installed at the bottom of the positive electrode secondary storage tank 15; the negative electrode storage tank 30 is connected to the negative electrode liquid inlet pipe bundle 26 and the negative electrode liquid return pipe bundle 25, and the negative electrode return pipe bundle 25 is provided with a negative electrode heat exchanger 31, a negative electrode filter 23, a negative electrode temperature sensor 32, and a negative electrode pump 22 from top to bottom, the negative electrode storage tank 30 is equipped with a negative electrode secondary storage tank 24, a negative electrode leakage sensor 21 is installed in the bottom space between the negative electrode secondary storage tank 24 and the negative electrode storage tank 30, and a heater 8 is installed at the bottom of the negative electrode secondary storage tank 24.

[0033] Each set of battery modules includes one power container 1 and an unlimited number of capacity containers 2.

[0034] The electrolyte storage tank uses a square storage tank that is formed by rotational molding. Its shape is highly consistent with the internal dimensions of the container, as well as the installation and maintenance space of pumps and other equipment, maximizing the use of the volume of the capacity container 2.

[0035] The capacity container 2 and the power container 1 are connected by a pipeline, and a circulation pump is installed in the capacity container 2 to pump the electrolyte from the storage tank into the battery stack to form an electrolyte circulation.

[0036] The positive electrode heat exchanger is installed at the positive electrode pump outlet. The positive electrode exits from the positive electrode heat exchanger. This part of the branch pipeline also serves the function of connecting the pump / heat exchanger and the battery stack to transport electrolyte and the anti-leakage coil. The corresponding main pipeline from the battery stack outlet to the storage tank is also replaced by a branch pipeline, which also serves the function of transporting electrolyte and the anti-leakage coil. The same is true for the negative electrode.

[0037] Each branch pipe can be connected to a stack interface, and can also supply liquid to multiple stacks at the same potential point at the same time (secondary branching is performed at the stack interface and is no longer directly connected to the stack structure through an extended coil)

[0038] A leakage collection tank made of waterproof and electrolyte corrosion resistant material is installed between each roto-molded storage tank and the inner wall of the container. The upper edge of the collection tank is higher than the liquid level in the tank, ensuring that when the tank or the equipment pipeline above it leaks, all the leakage can be collected to prevent the leakage from entering the container and corroding the box material and leaking to the outside of the battery module. One or more leakage alarms are installed between the leakage collection tank and the roto-molded storage tank to detect leakage failures in the first place. The materials of the leakage tank include but are not limited to PP, PE, PVC, PVDF, PTFE, TPO, rubber, metal with anti-corrosion coating, etc.

[0039] When a capacity container contains multiple roto-molded electrolyte tanks, there are metal partitions between the tanks to provide support and fixation for the tanks. When the tanks installed in the same container share a circulation pump, a connecting pipe is installed between the two tanks to ensure that the electrolyte height in the two tanks is level. In addition to the liquid connecting pipe, the gas phase of the tanks sharing the circulation pump is connected to ensure the balance of air pressure inside the tank.

[0040] The positive and negative electrolytes can be evenly distributed in multiple capacity containers, or can be filled in different capacity containers respectively.

[0041] There are corresponding openings at the connection between the power container and the capacity container as pipeline and cable passages. The upper and lower containers can be directly connected using hoses to offset the position deviation caused by pipeline installation and on-site construction connection.

[0042] There is an open door on the side of the power container as a maintenance surface, and the top of the first-layer capacity container is used as an operating platform for operation and maintenance personnel to walk. Safety fences are installed around the capacity container to prevent personnel and equipment from falling. Stairs are installed on the side of the capacity container. When multiple battery modules are placed close to each other, multiple battery modules can share the stairs.

[0043] The bottom, side walls and top of capacity containers and power containers can be installed with thermal insulation materials according to the use environment conditions, and heating equipment such as heating tapes, electric heating plates, heaters and air conditioners can be installed in the box when necessary.

[0044] There are several maintenance ports on the top of the capacity container, corresponding to the circulating pump, heat exchanger, tank manhole and other parts that require maintenance.

[0045] Each battery module is equipped with a battery management system (BMS) installed at the end or side of the capacity container, close to the operation and maintenance channel to facilitate daily inspection.

[0046] The radiator of the heat exchange system is also installed on the top of the capacity container in a position that does not affect other operation and maintenance openings.

[0047] A leakage collection tank is installed under each battery stack in the power container, and a leakage detector is installed in the tank.

[0048] The heat exchanger in the capacity container can be selected according to actual usage.

[0049] The above-mentioned embodiments are only preferred embodiments of the present invention, but not all feasible embodiments of the present invention. For those skilled in the art, any obvious changes made to the present invention without departing from the principle and spirit of the present invention should be considered to be included in the scope of protection of the claims of the present invention.

Claims

1. A stacked all-vanadium liquid flow battery system, characterized in that: The invention comprises a power container (1), a capacity container (2), a refrigerator (3), a frequency converter (4), and a DC bus box (5); a battery stack (6) is located in the power container (1); an electrolyte storage tank and a circulation pump are located in the capacity container (2); the power container (1), the refrigerator (3), and the frequency converter (4) are installed and fixed above the capacity container (2); the power container (1) and the capacity container (2) are connected via a pipeline; a DC bus box (5) is provided on the side of the capacity container (2); the DC bus box (5) and the power container (1) are connected via a pipeline; a BMS (27) is provided on the capacity container (2); and a DC bus box (28) is provided on the power container (1).

2. The all-vanadium liquid flow battery system of the stacked structure according to claim 1 is characterized in that: The power container (1) specifically comprises a battery stack (6), a SOC (11), an HCL sensor (10), a smoke sensor (12), a liquid leakage groove (7), a heater (8), and a pressure sensor (9). The battery stack (6) is provided with a plurality of them, each of which is equipped with a pressure sensor (9). The bottom of the battery stack (6) is provided with a liquid leakage groove (7). The battery stack (6) is connected to the SOC (11). The top of the power container (1) is provided with an HCL sensor (10) and a smoke sensor (12), and the lower side of the power container (1) is provided with a plurality of heaters (8).

3. The all-vanadium liquid flow battery system of the stacked structure according to claim 1 is characterized in that: The capacity container (2) specifically comprises a positive electrode storage tank (29), a negative electrode storage tank (30), a positive electrode liquid inlet pipe bundle (13), a positive electrode liquid return pipe bundle (14), a positive electrode secondary storage tank (15), a positive electrode heat exchanger (16), a positive electrode filter (17), a positive electrode pump (18), a positive electrode liquid leakage sensor (19), a positive electrode temperature sensor (20), a heater (8), a negative electrode liquid inlet pipe bundle (26), a negative electrode liquid return pipe bundle (25), a negative electrode secondary storage tank (24), a negative electrode filter (23), a negative electrode pump (22), and a negative electrode liquid leakage sensor (21). The positive electrode storage tank (29) is connected to the positive electrode liquid inlet pipe bundle (13) and the positive electrode liquid return pipe bundle (14). The positive electrode liquid return pipe bundle (14) is provided with a positive electrode heat exchanger (16), a positive electrode filter (17), a positive electrode temperature sensor (21) in order from top to bottom. 0), a positive electrode pump (18), a positive electrode secondary storage tank (15) is installed outside the positive electrode storage tank (29), a positive electrode leakage sensor (19) is installed in the bottom space between the positive electrode secondary storage tank (15) and the positive electrode storage tank (29), and a heater (8) is installed at the bottom of the positive electrode secondary storage tank (15); a negative electrode storage tank (30) is connected to a negative electrode liquid inlet pipe bundle (26) and a negative electrode liquid return pipe bundle (25), and a negative electrode heat exchanger (31), a negative electrode filter (23), a negative electrode temperature sensor (32), and a negative electrode pump (22) are arranged on the negative electrode liquid return pipe bundle (25) from top to bottom; a negative electrode secondary storage tank (24) is installed outside the negative electrode storage tank (30), a negative electrode leakage sensor (21) is installed in the bottom space between the negative electrode secondary storage tank (24) and the negative electrode storage tank (30), and a heater (8) is installed at the bottom of the negative electrode secondary storage tank (24).

4. The all-vanadium liquid flow battery system of the stacked structure according to claim 1, characterized in that: There are multiple capacity containers (2) and only one power container (1).

5. The all-vanadium liquid flow battery system of the stacked structure according to claim 3 is characterized in that: The upper edges of the positive electrode secondary storage tank (15) and the negative electrode secondary storage tank (24) are higher than the liquid level in the storage tanks.

6. The all-vanadium liquid flow battery system of the stacked structure according to claim 2, characterized in that: The material of the leakage trough (7) includes PP, PE, PVC, PVDF, PTFE, TPO, rubber, and metal with an anti-corrosion coating.

7. The all-vanadium liquid flow battery system of the stacked structure according to claim 3 is characterized in that: A plurality of the positive electrode liquid leakage sensors (19) and the negative electrode liquid leakage sensors (21) are provided.

8. The all-vanadium liquid flow battery system of the stacked structure according to claim 3 is characterized in that: The positive electrode heat exchanger (16) and the negative electrode heat exchanger (31) are provided in 0 or 1 number.

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