Online liquid blowing device for flow battery stack

Abstract

The utility model provides an online liquid blowing device for a redox flow battery stack. The online liquid blowing device comprises positive and negative electrode liquid storage tanks, a liquid return pipe, a liquid inlet pipe, a liquid blowing gas pipe and corresponding control valves, wherein one end of the liquid return pipe is connected with the top of the galvanic pile, and the other end is connected with the upper part of the side wall of the liquid storage tank and is provided with a liquid return ball valve for cutting off an electrolyte backflow path; the liquid inlet pipe is connected with the bottom of the liquid storage tank and a stack bottom interface; a magnetic pump and a liquid inlet valve are configured to realize electrolyte circulating conveying; one end of the liquid blowing gas pipe is connected with an external inert gas source, and the other end of the liquid blowing gas pipe is connected into the liquid return pipe close to the galvanic pile section through a gas pipe joint and is provided with a liquid return valve for controlling gas introduction; an exhaust valve is arranged at the top of the liquid storage tank. The utility model solves the problems of low efficiency and tedious process of the traditional electric pile liquid discharge process, has high efficiency, safety and environmental protection property, and is suitable for the automatic production requirements of flow battery manufacturing and testing links.

Description

Technical Field

[0001] This utility model belongs to the field of flow battery technology, and in particular relates to an online liquid blowing device for flow battery stacks. Background Technology

[0002] In the research and development and production of vanadium redox flow battery stacks, electrical performance testing is a crucial step to ensure that their performance meets standards. After testing, to prevent corrosion, crystallization blockage, and other problems caused by electrolyte residue, and to ensure stability and safety during subsequent large-scale applications, the electrolyte inside the battery stack must be completely drained. This operation not only helps protect the battery's performance and extend its lifespan, but also, considering the high value of the electrolyte itself, effectively recovers excess electrolyte to achieve resource recycling, thereby improving overall economic efficiency. Therefore, professional processing methods are essential for optimizing the application of vanadium redox flow batteries.

[0003] Existing electrolyte drainage technologies include gravity drainage, vacuum suction, and gas purging. Gravity drainage is suitable for small fuel cell stacks, such as laboratory-scale devices (power < 1 kW), but its drainage efficiency and thoroughness are insufficient for larger power stacks (e.g., a 32 kW stack weighing approximately 1.2 tons). Vacuum suction is more suitable for complete drainage operations requiring precise control in laboratory environments, but its complexity and cost make it unsuitable for large-scale production applications. In contrast, gas purging is suitable for medium to large-sized fuel cell stacks (power ≥ 10 kW) and enables rapid drainage. However, in practice, this process typically requires moving the tested stack to a specific location, manually introducing gas, and repeatedly controlling the gas flow to drain the electrolyte. This process is monotonous and repetitive, consuming significant time and manpower, increasing operating costs, and hindering efficient implementation in large-scale applications. Summary of the Invention

[0004] The purpose of this utility model embodiment is to provide an online electrolyte blowing device for flow battery stacks, which solves the problems of low efficiency, high dependence on manual labor, and unsuitability for large-scale production, and achieves rapid, automatic, and thorough electrolyte discharge and recycling.

[0005] To solve the above-mentioned technical problems, the technical solution adopted by this utility model is an online liquid blowing device for a flow battery stack, comprising:

[0006] Liquid storage tanks, including positive electrode storage tanks and negative electrode storage tanks;

[0007] The return pipe is connected at one end to the top of the fuel cell stack and at the other end to the upper side wall of the storage tank. The return pipe is equipped with a return ball valve.

[0008] The liquid inlet pipe is connected at one end to the bottom of the side wall of the liquid storage tank and at the other end to the bottom interface of the fuel cell stack. The liquid inlet pipe is equipped with a magnetic pump and a liquid inlet valve.

[0009] The liquid blowing gas pipe is connected to an external inert gas source at one end and to the section of the return liquid pipe near the fuel cell stack at the other end through a gas pipe connector.

[0010] A return valve is provided on the return pipe between the gas pipe connector and the fuel cell stack.

[0011] The top of the storage tank is equipped with an exhaust valve to release the gas generated during the liquid blowing process.

[0012] Furthermore, the return ball valve is located on the return pipe between the side wall of the storage tank and the gas pipe connector, and is used to block the flow of electrolyte and gas into the storage tank.

[0013] Furthermore, the magnetic pump installed on the inlet pipe is located near the bottom of the side wall of the storage tank, and the inlet valve is located near the bottom interface of the fuel cell stack.

[0014] Furthermore, the exhaust valve is a gas flow control valve with a scale display.

[0015] Furthermore, an independent air valve is provided at the connection between the blowing air pipe and the air pipe connector, and the air pipe valve is a two-position three-way valve.

[0016] Furthermore, the vent valve at the top of the storage tank is connected to a gas recovery device or a gas treatment device.

[0017] Compared with existing technologies, the beneficial effects of this utility model are as follows: This utility model achieves rapid discharge and efficient recovery of electrolyte through the synergistic effect of inert gas purging and gravity drainage, improving resource utilization; without disassembling or transferring the fuel cell stack, charge and discharge testing and liquid purging and drainage operations can be completed at the testing station, forming an integrated process and significantly improving production efficiency; a gas flow control valve with a scale display is used in conjunction with an independent gas source to achieve precise control of gas pressure and flow, and environmental impact is reduced by connecting a gas recovery device; the system is equipped with multiple control components such as a magnetic pump, return ball valve, inlet valve, and return valve to ensure pipeline sealing and operational safety, preventing gas backflow and contamination of the storage tank; it also has the ability to selectively drain the left and right cavities of the fuel cell stack, enhancing its applicability and flexibility; in addition, this device is highly integrated with existing production lines, and the fuel cell stack automatically flows through the logistics line, realizing full-process automation from positioning and testing to liquid drainage, reducing manual intervention and handling risks, and effectively improving equipment utilization and the overall intelligence level of the production line. Attached Figure Description

[0018] To more clearly illustrate the technical solutions in the embodiments of this utility model or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this utility model. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0019] Figure 1 This is a perspective view of the liquid blowing device in this embodiment;

[0020] Figure 2 This is a side view of the liquid blowing device in this embodiment;

[0021] In the diagram, 1 is the liquid storage tank; 2 is the fuel cell stack; 3 is the liquid blowing pipe; 4 is the return ball valve; 5 is the return pipe; 6 is the inlet pipe; 7 is the air valve; 8 is the air connector; 9 is the exhaust valve; 10 is the inlet valve; 11 is the return valve; and 12 is the magnetic pump. Detailed Implementation

[0022] The technical solutions of the present utility model will be clearly and completely described below with reference to the accompanying drawings of the embodiments. Obviously, the described embodiments are only some embodiments of the present utility model, and not all embodiments. Based on the embodiments of the present utility model, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the protection scope of the present utility model.

[0023] like Figure 1 , Figure 2 This embodiment provides an online liquid blowing device for a flow battery stack, a device that combines gas blowing and gravity drainage, including a liquid storage tank 1, a blowing air pipe 3, a return ball valve 4, an inlet pipe 6, a return pipe 5, an air pipe valve 7, an air pipe connector 8, and an exhaust valve 9.

[0024] In some specific embodiments, the liquid storage tank 1 system includes a positive electrode liquid storage tank and a negative electrode liquid storage tank; a return pipe 5 and an inlet pipe 6 are provided between the liquid storage tank 1 and the fuel cell stack 2. Specifically, one end of the return pipe 5 is connected to the top of the fuel cell stack 2, and the other end is connected to the upper area of ​​the side wall of the liquid storage tank 1, which is used to realize fluid communication between the fuel cell stack 2 and the liquid storage tank 1, so that after the electrolyte completes the charging and discharging reaction in the fuel cell stack 2, it can return to the corresponding liquid storage tank 1 through the return pipe 5. A return ball valve 4 is provided on the return pipe 5. The return ball valve 4 is used to cut off the flow path of the electrolyte under specific operating conditions, thereby guiding the inert gas directly into the interior of the fuel cell stack 2, rather than flowing into the liquid storage tank 1 through the return pipe 5. This design can ensure that the inert gas is accurately introduced into the fuel cell stack 2, while avoiding the problem of reduced liquid blowing efficiency caused by its simultaneous entry into the liquid storage tank 1. On the side near the fuel cell stack 2, specifically on the pipe section between the return ball valve 4 and the fuel cell stack 2, a gas pipe connector 8 and a return valve 11 are sequentially arranged. The return valve 11 is used to control the on / off state of the electrolyte in the return pipe 5. Furthermore, the gas pipe connector 8 is also connected to the liquid blowing pipe 3, and an exhaust valve 9 is provided at the connection point between the liquid blowing pipe 3 and the gas pipe connector 8 to regulate and control the gas emission process.

[0025] In some possible implementations, the exhaust valve 9 is specifically a graduated gas flow control valve. In this implementation, the exhaust valve 9 is specifically an ARX20-02 control valve manufactured by SMC Corporation of Japan. Any gas flow control valve that can realize gas flow regulation and display functions is within the scope of this implementation.

[0026] In some specific embodiments, the other end of the blowing gas pipe 3 is connected to an independent gas source, which may include a nitrogen generator or a high-pressure nitrogen cylinder.

[0027] One end of the inlet pipe 6 is connected to the bottom area of ​​the side wall of the storage tank 1, and the other end is connected to the bottom interface of the fuel cell stack 2. The inlet pipe 6 is used to transport the electrolyte in the storage tank 1 to the interior of the fuel cell stack 2. A magnetic pump 12 is installed on a section of the inlet pipe 6 near the storage tank 1. The magnetic pump 12 is used to provide power for the transport of electrolyte from the storage tank 1 to the fuel cell stack 2. In this embodiment, the magnetic pump 12 can be an AMX-86JFGACV-1X model pump body manufactured by Xieci Company; in addition, any drive device that can achieve the same or similar transport function is within the technical scope covered by this embodiment.

[0028] In some specific embodiments, an inlet valve 10 is installed on the section of the inlet pipe 6 near the fuel cell stack 2. The inlet valve 10 is used to control the flow of electrolyte and maintain the airtightness of the fuel cell stack 2. An exhaust valve 9 is provided at the top of the storage tank 1. The exhaust valve 9 is used to release the purging gas during the liquid blowing process. Optionally, the exhaust valve 9 can be connected to a gas recovery device or a gas treatment device to prevent the gas generated during the liquid blowing process from being directly discharged into the atmosphere, thereby achieving environmentally friendly emissions and effective resource recovery and utilization.

[0029] The working process of the online electrolyte blowing device described in this embodiment is as follows: First, the corresponding electrolytes are injected into the positive and negative electrode storage tanks 1 respectively. The magnetic pump 12 installed on the inlet pipe 6 is started. Under the pumping action, the electrolyte is transported from the bottom of the side wall of the storage tank 1 to the bottom interface of the battery stack 2 through the inlet pipe 6, thereby completing the electrolyte filling operation of the battery stack 2 and providing the necessary operating conditions for subsequent battery performance testing. After the charge and discharge performance test of the battery stack 2 is completed, there is no need to disassemble or transfer the battery stack 2, and it can directly enter the electrolyte blowing and draining stage, realizing the continuous execution of testing and electrolyte blowing functions at the same station. Specifically, firstly, the return ball valve 4 on the return pipe 5 is closed to prevent the electrolyte and inert gas from returning to the storage tank 1 via the return path. Then, the vent valve 7 at the vent connector 8 and the exhaust valve 9 at the top of the storage tank 1 are opened, and an external inert gas source (such as a nitrogen cylinder) is connected to the vent connector 8 via the vent pipe 3, forming a complete gas introduction path. The vent valve 7 is a two-position three-way valve used to control the on / off state and flow direction of the inert gas. After nitrogen is introduced, the pressure and flow rate of the input gas are adjusted to allow nitrogen to enter the fuel cell stack 2 from the return interface at the top of the stack. The gas pressure then pushes the electrolyte remaining in the fuel cell stack 2 cavity to flow in the reverse direction along the inlet pipe 6, ultimately returning to the corresponding storage tank 1, achieving effective electrolyte recovery. During this process, the positive pressure generated inside the storage tank 1 due to gas accumulation can be released through the exhaust valve 9, ensuring the safety and stability of the system operation. The gas emitted after liquid blowing is recovered or treated by a gas recovery device or gas treatment device installed at the outlet of exhaust valve 9 to prevent nitrogen or other inert gases emitted during the liquid blowing process from directly escaping into the atmosphere, thereby avoiding potential environmental impact. The entire liquid blowing process has a reasonable structure, closed-loop flow, and precise control, enabling safe, efficient, and controllable electrolyte purging and recovery operations without introducing additional manual intervention. It is suitable for integrated applications in automated production lines.

[0030] This embodiment combines gas purging and gravity drainage mechanisms, effectively improving drainage efficiency and allowing online drainage to be completed in approximately ten minutes. Furthermore, by controlling the on / off states of the return valve 11 and the inlet valve 10, independent drainage operations can be performed on the left and right cavities of the fuel cell stack 2, providing good controllability and applicability.

[0031] During the testing of fuel cell stack 2, the fuel cell stack 2 under test is transported to a designated location on the testing platform via a logistics line, where the corresponding performance testing operations are completed. After the test, there is no need to transfer the fuel cell stack 2 to other equipment or workstations; the device provided in this embodiment can be used directly to purge and drain the residual electrolyte inside the fuel cell stack 2. This process achieves integrated flow control from the positioning of the fuel cell stack 2, testing, and draining operations, significantly improving the continuity and efficiency of the overall testing and draining operations. Through integrated system design, the testing platform and the liquid blowing device are arranged on the same production line, avoiding the process complexity, increased time costs, and potential handling risks associated with transferring the fuel cell stack 2 to a dedicated liquid blowing device for draining in traditional processes. Thus, without changing the production line layout of the fuel cell stack 2, seamless connection and automated flow from testing to liquid blowing are achieved, further improving production cycle time and system operation stability. In addition, after purging and draining, the fuel cell stack 2 can be automatically transferred to the subsequent process section or the next workstation via the logistics line, providing technical support and equipment assurance for realizing the intelligent and continuous operation of the entire manufacturing or testing process. This method not only optimizes the production process but also reduces the degree of manual intervention, and has good prospects for engineering application and promotion value.

[0032] The above description is merely a preferred embodiment of this utility model and is not intended to limit the scope of protection of this utility model. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of this utility model are included within the scope of protection of this utility model.

Claims

1. An online liquid blowing device for a flow battery stack, characterized in that, include: The liquid storage tank (1) includes a positive electrode liquid storage tank and a negative electrode liquid storage tank; The return pipe (5) is connected to the top of the fuel cell stack (2) at one end and to the upper side wall of the storage tank (1) at the other end. The return pipe (5) is equipped with a return ball valve (4). The liquid inlet pipe (6) is connected at one end to the bottom of the side wall of the liquid storage tank (1) and at the other end to the bottom interface of the fuel cell stack (2). The liquid inlet pipe (6) is equipped with a magnetic pump (12) and a liquid inlet valve (10). The blowing gas pipe (3) is connected to an external inert gas source at one end and to the section of the return pipe (5) near the fuel cell stack (2) via a gas pipe connector (8); A return valve (11) is provided on the return pipe (5) between the gas pipe connector (8) and the fuel cell stack (2). The top of the liquid storage tank (1) is equipped with an exhaust valve (9) for discharging the gas generated during the liquid blowing process.

2. The online liquid blowing device for a flow battery stack according to claim 1, characterized in that: The return ball valve (4) is located on the return pipe (5) between the side wall of the storage tank (1) and the gas pipe connector (8), and is used to block the flow of electrolyte and gas to the storage tank (1).

3. The online liquid blowing device for a flow battery stack according to claim 1, characterized in that: The magnetic pump (12) installed on the inlet pipe (6) is located near the bottom of the side wall of the storage tank (1), and the inlet valve (10) is located near the bottom interface of the fuel cell stack (2).

4. The online liquid blowing device for a flow battery stack according to claim 1, characterized in that: The exhaust valve (9) is a gas flow control valve with a scale display.

5. The online liquid blowing device for a flow battery stack according to claim 1, characterized in that: An independent air pipe valve (7) is provided at the connection between the blowing air pipe (3) and the air pipe connector (8). The air pipe valve (7) is a two-position three-way valve.

6. The online liquid blowing device for a flow battery stack according to claim 1, characterized in that: The exhaust valve (9) at the top of the storage tank (1) is connected to a gas recovery device or a gas processing device.

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