An apparatus for recovering vanadium cell capacity in real time online

Abstract

The utility model relates to a kind of device for recovering vanadium battery capacity on-line in real time, comprising: sampling system, connect with concentration detection system, negative electrode storage tank, positive electrode storage tank by pipeline, and with central controller electric connection;Liquid level meter, be located in negative electrode storage tank and positive electrode storage tank, with central controller electric connection;Recovery agent control system, connect with positive electrode storage tank and negative electrode storage tank by pipeline, with central controller electric connection;Concentration detection system, with central controller electric connection.The utility model has high degree of automation, without human intervention, while battery system does not need to stop under the condition, real-time recovery battery capacity, make battery capacity in high position operation, recovery agent raw material is simple and easy to obtain, low in cost, and effect is remarkable and the like advantages.

Description

Technical Field

[0001] This utility model relates to the field of flow battery applications and energy recovery, and in particular to a real-time capacity recovery device for vanadium redox flow batteries. Background Technology

[0002] Vanadium redox flow batteries are a novel type of energy storage system. Compared with traditional energy storage methods, they feature fast charge and discharge response, large and adjustable charging capacity, high battery efficiency, and simple battery structure, giving them significant advantages in energy storage, especially in the stationary storage of renewable energy. The positive and negative electrode electrolyte solutions of vanadium redox flow batteries contain solutions of V(V) / V(Ⅳ) and V(Ⅲ) / V(Ⅱ) vanadium compounds, respectively. These compounds are not only the active materials for energy storage but also the core of the energy storage and conversion process in vanadium redox flow batteries.

[0003] Due to the cross-reaction of vanadium ions and the continuous occurrence of side reactions, after long-term battery operation, the vanadium ions in the negative electrode electrolyte may mainly be V ions. 2+ The vanadium ions in the positive electrode electrolyte are mainly VO. 2+ Or, the vanadium ions in the negative electrode electrolyte may mainly be V. 3+ The vanadium ions in the positive electrode electrolyte are mainly VO2. + This imbalance in the electrolyte between the positive and negative electrodes renders the electrolyte unusable, making it difficult to maintain the flow battery's capacity and consequently affecting its lifespan. Therefore, there is an urgent need for a device capable of real-time detection of vanadium ion concentration and timely restoration of battery capacity. Utility Model Content

[0004] To address the aforementioned problems, the purpose of this invention is to provide an online real-time capacity recovery device for vanadium redox flow batteries, thereby solving the capacity decay problem and enabling long-term battery operation and efficient utilization of the electrolyte.

[0005] The technical solution adopted by this utility model to achieve the above-mentioned objective is: a device for online real-time recovery of vanadium battery capacity, comprising:

[0006] The sampling system is connected to the concentration detection system, the negative electrode storage tank, and the positive electrode storage tank via pipelines, and is electrically connected to the central controller.

[0007] The level gauge is installed outside the negative and positive storage tanks and is electrically connected to the central controller.

[0008] The restorer control system is connected to the positive and negative electrode storage tanks via pipelines and is electrically connected to the central controller.

[0009] The concentration detection system is electrically connected to the central controller.

[0010] The sampling system is an automatic sampler. The two inlets of the automatic sampler are respectively located on the pipeline between the outlet of the negative electrode storage tank and the inlet of the negative electrode of the fuel cell stack, and on the pipeline between the outlet of the positive electrode storage tank and the inlet of the positive electrode of the fuel cell stack. The two corresponding outlets are respectively connected to the two collection ports of the automatic sampler in the concentration detection system. The control port and signal output port of the automatic sampler are connected to the central controller.

[0011] The outer wall of the positive electrode tank is provided with a first U-shaped tube connected to it, and the outer wall of the negative electrode tank is provided with a second U-shaped tube connected to it; there are two level gauges, which are respectively installed at the lower end of the first U-shaped tube and the lower end of the second U-shaped tube, and are connected to the central controller via cables.

[0012] The restorer control system consists of two systems, which are respectively located above the positive electrode tank and the negative electrode tank, and are connected to the positive electrode tank and the negative electrode tank respectively through pipelines.

[0013] The inlet of the restorer control system is used to input the restorer raw material through a pipeline, and the outlet is connected to the positive or negative electrode storage tank through a pipeline. The restorer control system is one of a self-priming pump, a peristaltic pump, or an automatic solid feeder, and its control terminal is connected to a central controller.

[0014] The concentration detection system includes a vanadium ion concentration detection device and an automatic sampler connected thereto. The vanadium ion concentration detection device is one of a spectrophotometer, potentiometric titrator, spectrometer, or colorimeter. The control port and signal output terminal of the vanadium ion concentration detection device are connected to a central controller.

[0015] This utility model has the following beneficial effects and advantages:

[0016] 1. This utility model employs a sampling system and a concentration detection system. The sampling system directly samples the electrolyte in the negative or positive electrode storage tank, ensuring timely and accurate sampling. It can also automatically extract the electrolyte from the positive and negative electrode storage tanks at irregular intervals and provide timely feedback to the concentration detection device. After measuring the vanadium ion concentration, the addition measurement of the restoring agent is fed back to the central controller to control the operation of the restoring agent control system.

[0017] 2. The electrolyte in the positive and negative electrode tanks is automatically extracted by the sampling system, and the concentration of vanadium ions in each valence state is detected by the concentration detection system. The volume of the positive and negative electrode electrolyte is obtained according to the level gauge, and the amount of recovery agent required can be determined. The central controller controls the recovery agent control system to add the specified amount of recovery agent to the positive or negative electrode tank through the pipeline, so as to adjust the amount of vanadium ions in each valence state in real time, thereby achieving the purpose of restoring battery capacity.

[0018] 3. The online real-time vanadium redox flow battery capacity recovery device provided by this utility model can effectively solve the problem of battery capacity recovery after degradation. This utility model has the advantages of high automation, no need for human intervention, real-time recovery of battery capacity without stopping the battery system, keeping the battery capacity at a high level, simple and readily available raw materials for the recovery agent, low cost, and significant effect. Attached Figure Description

[0019] Figure 1 This is a schematic diagram illustrating the structural principle of the online real-time capacity recovery device described in this utility model. Detailed Implementation

[0020] The present invention will now be described in further detail with reference to the accompanying drawings and embodiments.

[0021] This invention relates to the application and energy recovery of flow batteries, specifically a real-time capacity recovery device for vanadium redox flow batteries, addressing the capacity decay problem in existing flow batteries. The device automatically detects the amount of vanadium ions in each valence state using a vanadium ion concentration detection device. Based on existing technology calculations, it sends a command to the recovery agent control system to add a specified amount of recovery agent, thus restoring battery capacity in real time. This invention enables online detection of vanadium ions and online addition of the recovery agent, solving the problem of pentavalent or divalent vanadium accumulation during battery operation, ultimately resolving capacity decay and achieving long-term battery operation and efficient electrolyte utilization.

[0022] like Figure 1 As shown, an online real-time capacity recovery device for vanadium redox flow batteries integrates a battery management system, a concentration detection system (vanadium ion concentration detection system), a sampling system, a level gauge, and a recovery agent control system into a central controller via cables. The sampling system, level gauge, and recovery agent control system are connected to the positive and negative electrode storage tanks via pipelines. The sampling system is connected to the concentration detection system via pipelines. The central controller instructs the sampling system to automatically extract electrolyte from the positive and negative electrode storage tanks at irregular intervals and instructs the vanadium ion concentration detection system to detect the concentration of vanadium ions in each valence state. Based on the electrolyte volume obtained from the level gauge, the amount of vanadium ions in each valence state is calculated. Then, based on the stoichiometric ratio of vanadium ions to the recovery agent, the required amount of recovery agent is finally calculated using the aforementioned prior art. Subsequently, the central controller sends instructions to the recovery agent control system via cables. The recovery agent control system adds the specified amount of recovery agent to the positive or negative electrode storage tank through pipelines, adjusting the amount of vanadium ions in each valence state in real time to achieve the purpose of restoring battery capacity.

[0023] The output terminals of the concentration detection system (vanadium ion concentration detection system), sampling system, level gauge, and regenerating agent control system are connected to the input terminals of the central controller via cables. The central controller is also connected to the battery management system, the negative electrode pump (located between the battery and the negative electrode tank), and the positive electrode pump (located between the battery and the positive electrode tank). This connection enables control of the positive and negative electrode pumps, data acquisition, storage, and feedback from various flow, pressure, and temperature sensors within the battery system, ensuring the normal operation of the battery system.

[0024] A U-shaped tube communicating with the storage tank is installed on the outer side of the tank. The level gauge is located at the lower end of the U-shaped tube, which is open. The sensor of the level gauge is located at the opening and in contact with the liquid. The outlet of the restoring agent control system is located above the positive and negative electrode storage tanks and is connected to the storage tanks via pipelines. The level gauge is connected to the I / O port of the central controller via a cable to provide feedback on the liquid level information and thus obtain the electrolyte volume.

[0025] The sampling system is an automatic sampler, installed on the pipeline between the liquid outlet of the storage tank and the inlet of the fuel cell stack. The sampling system can automatically complete the sampling operation according to the instructions of the central controller and deliver the sample to the automatic sampler in the concentration detection system. In this embodiment, one sampler can be connected to both the positive and negative electrode pipelines simultaneously, collecting samples from both electrodes respectively. The sampling input terminal of the automatic sampler is connected to the pipeline via a T-junction. The automatic sampler has multiple outlets. The sample collected by the automatic sampler is transferred to the automatic sampler of the concentration monitoring system. The signal output port of the automatic sampler is connected to the I / O port of the central controller for feedback of sample information, including sampling time, positive and negative electrode information, and sample volume.

[0026] The central controller is responsible for controlling the operation of each system, processing data, and issuing commands.

[0027] The concentration detection system described is existing technology, comprising a vanadium ion concentration detection device and a matching autosampler. Typically, one detection device is configured with one autosampler, and each autosampler has multiple sample collection positions. The vanadium ion concentration detection device is one of a spectrophotometer, potentiometric titrator, spectrometer, or colorimeter. The vanadium ion concentration detection device receives instructions from the central controller via a control terminal to perform concentration detection and feeds back the detected vanadium ion concentration to the central controller through the central controller's I / O port.

[0028] The volumes of the positive and negative electrode electrolytes are monitored in real time using level gauges.

[0029] The restoring agent control system is located above the storage tank and connected to the tank via pipeline. The restoring agent control system is one of a self-priming pump, a peristaltic pump, or an automatic solid feeder. Its control terminal is connected to the I / O terminal of a central controller, and its opening and closing are controlled by the central controller. The inlet of the restoring agent control system is connected to the restoring agent raw material via pipeline, and its outlet is connected to the storage tank via pipeline.

[0030] Example 1

[0031] Taking a 10kW / 20kWh all-vanadium redox flow battery system as the research object, the battery management system, vanadium ion concentration detection system, sampling system, level gauge, and regenerator control system are integrated into the central controller via cables. The battery management system contains electrical components. Through integration, it can realize the control of positive and negative electrode pumps, data acquisition, storage, and feedback of various flow, pressure, temperature and other sensors arranged in the battery system, so as to ensure the normal operation of the battery system. The sampling system, level gauge, and restorer control system are connected to the positive and negative electrode storage tanks via pipelines. The sampling system is connected to the concentration detection system via pipelines. The central controller instructs the sampling system to automatically extract electrolyte from the positive and negative electrode storage tanks at irregular intervals, and instructs the vanadium ion concentration detection system to detect the concentration of vanadium ions in each valence state. Based on the volume of electrolyte in the positive and negative electrodes obtained from the level gauge, the amount of vanadium ions in each valence state is calculated. Then, based on the stoichiometric ratio of vanadium ions to restorer, the required amount of restorer is calculated. Subsequently, the central controller sends a command to the restorer control system via cable. The restorer control system adds the specified amount of restorer to the positive or negative electrode storage tank through pipelines, adjusting the amount of vanadium ions in each valence state in real time to achieve the purpose of restoring battery capacity.

[0032] The vanadium ion concentration detection equipment is a potentiometric titrator, the system storage tank is equipped with an electronic level gauge, and the restoring agent control system is an automatic solid feeder. The restoring agent is citric acid.

[0033] The central controller controls the potentiometric titrator to automatically detect vanadium ion concentration every 10 days. The electronic level gauge records and provides feedback on the electrolyte volume in real time. The central processor calculates the amount of citric acid used as the restoring agent using the existing stoichiometric formula for vanadium ions and the restoring agent. The central processor then sends instructions to the automatic solid feeder, which adds the restoring agent to the positive electrode tank. Data from Example 1 are shown in Table 1.

[0034] Table 1

[0035] Test days / day Dosage of restorative agent / kg Before restoration capacity / kWh Restored capacity / kWh Volume retention rate after recovery / % 0 - 20.45 - - 10 0.7 18.93 19.82 96.9 20 0.84 18.6 19.77 96.7 30 0.875 18.32 19.75 96.6 40 0.98 18.01 19.69 96.3 50 1.12 17.62 19.63 96.0 60 1.05 17.47 19.72 96.4

[0036] Comparative Example 1

[0037] Taking a 10kW / 20kWh all-vanadium redox flow battery system as the research object, without using the device described in this utility model, and operating for the same amount of time, the data of Comparative Example 1 are shown in Table 2:

[0038] Table 2

[0039] Test days / day Capacity / Wh Capacity retention rate / % 0 20.07 - 10 18.91 94.2 20 18.07 90.0 30 17.31 86.2 40 16.59 82.7 50 15.97 79.6 60 15.48 77.1

[0040] By comparing Example 1 with Comparative Example 1, it was found that the battery system without the device of this utility model had a capacity retention rate of 77.1% after 60 days of operation, while the battery system using the device of this utility model had a capacity retention rate of 96.4% after 60 days of operation, showing significant effect and obvious capacity recovery.

[0041] Example 2

[0042] Taking a 1kW / 1kWh all-vanadium redox flow battery system as the research object, the battery management system, vanadium ion concentration detection system, sampling system, level gauge, and restorer control system are integrated into a central controller via cables. The sampling system, level gauge, and restorer control system are connected to the positive and negative electrode tanks via pipelines. The sampling system is connected to the concentration detection system via pipelines. The central controller instructs the sampling system to automatically extract electrolyte from the positive and negative electrode tanks at irregular intervals and instructs the vanadium ion concentration detection system to detect the concentration of vanadium ions of various valence states. Based on the electrolyte volume of the positive and negative electrodes obtained from the level gauge, the amount of vanadium ions of various valence states is calculated. Then, based on the stoichiometric ratio of vanadium ions to restorer, the required amount of restorer is calculated. Subsequently, the central controller sends instructions to the restorer control system via cables. The restorer control system adds the specified amount of restorer to the positive or negative electrode tank through pipelines, adjusting the amount of vanadium ions of various valence states in real time to achieve the purpose of restoring battery capacity.

[0043] The vanadium ion concentration detection equipment is a colorimeter, the system storage tank is equipped with an electronic level gauge, and the restoring agent control system is a peristaltic pump. The restoring agent is 30% hydrogen peroxide by mass.

[0044] The central controller controls the colorimeter to automatically detect vanadium ion concentration every 5 days, the electronic level gauge records and provides feedback on the electrolyte volume in real time, the central processor calculates the dosage of the restoring agent hydrogen peroxide using a formula, and the central processor sends instructions to the peristaltic pump, which completes the addition of the restoring agent in the negative electrode tank. Data from Example 2 are shown in Table 3:

[0045] Table 3

[0046] Test days / day Dosage of restorative agent / g Before restoration capacity / Wh Restored capacity / Wh Volume retention rate after recovery / % 0 - 1017 - - 5 160 963 983 96.7 10 198 942 986 97.0 15 265 911 985 96.9 20 260 915 980 96.4 25 252 931 977 96.1 30 263 933 979 96.3

[0047] Comparative Example 2

[0048] Taking a 1kW / 1kWh all-vanadium redox flow battery system as the research object, without using the device described in this utility model, the data of Comparative Example 2, which operates for the same amount of time, are shown in Table 4:

[0049] Table 4

[0050] Test days / day Capacity / Wh Capacity retention rate / % 0 1022 - 5 961 94.0 10 898 87.9 15 844 82.6 20 796 77.9 25 749 73.3 30 701 68.6

[0051] By comparing Example 2 with Comparative Example 2, it was found that the battery system without the device described in this utility model had a capacity retention rate of 68.6% after 30 days of operation, while the battery system using the device described in this utility model had a capacity retention rate of 96.3% after 30 days of operation, showing significant effect and obvious capacity recovery.

[0052] The central controller and other structures involved in this utility model are conventional choices, and this utility model has no innovation in software and programming. It only protects the structural technical features such as hardware connection relationships and positional relationships. Those skilled in the art can realize the functions of this utility model and solve the technical problems of this utility model by using the structural features described in this utility model and combining them with conventional programming logic.

Claims

1. A device for online real-time capacity recovery of vanadium batteries, characterized in that, include: The sampling system is connected to the concentration detection system, the negative electrode storage tank, and the positive electrode storage tank via pipelines, and is electrically connected to the central controller. The level gauge is installed outside the negative and positive storage tanks and is electrically connected to the central controller. The restorer control system is connected to the positive and negative electrode storage tanks via pipelines and is electrically connected to the central controller. The concentration detection system is electrically connected to the central controller.

2. The device for online real-time recovery of vanadium battery capacity according to claim 1, characterized in that, The sampling system is an automatic sampler. The two inlets of the automatic sampler are respectively located on the pipeline between the outlet of the negative electrode storage tank and the inlet of the negative electrode of the fuel cell stack, and on the pipeline between the outlet of the positive electrode storage tank and the inlet of the positive electrode of the fuel cell stack. The two corresponding outlets are respectively connected to the two collection ports of the automatic sampler in the concentration detection system. The control port and signal output port of the automatic sampler are connected to the central controller.

3. The device for online real-time recovery of vanadium battery capacity according to claim 1, characterized in that, The outer wall of the positive electrode tank is provided with a first U-shaped tube connected to it, and the outer wall of the negative electrode tank is provided with a second U-shaped tube connected to it; there are two level gauges, which are respectively installed at the lower end of the first U-shaped tube and the lower end of the second U-shaped tube, and are connected to the central controller via cables.

4. The device for online real-time recovery of vanadium battery capacity according to claim 1, characterized in that, The restorer control system consists of two systems, which are respectively located above the positive electrode tank and the negative electrode tank, and are connected to the positive electrode tank and the negative electrode tank respectively through pipelines.

5. The device for online real-time recovery of vanadium battery capacity according to claim 4, characterized in that, The inlet of the recovery agent control system is used to input the recovery agent raw material through a pipeline, and the outlet is connected to the positive electrode storage tank or the negative electrode storage tank through a pipeline.

6. The device for online real-time recovery of vanadium battery capacity according to claim 1 or 5, characterized in that, The restorer control system is one of a self-priming pump, a peristaltic pump, or an automatic solid feeder, and the control terminal is connected to the central controller.

7. The device for online real-time recovery of vanadium battery capacity according to claim 1, characterized in that, The concentration detection system includes a vanadium ion concentration detection device and an automatic sampler connected thereto. The vanadium ion concentration detection device is one of a spectrophotometer, potentiometric titrator, spectrometer, or colorimeter. The control port and signal output terminal of the vanadium ion concentration detection device are connected to a central controller.

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