Multi-parameter online detection system and method for all-vanadium redox flow battery electrolyte

Abstract

The invention relates to a multi-parameter online detection system and method for an all-vanadium redox flow battery electrolyte. The system mainly comprises a sampling pipeline, an integrated detection module and a fluid control module, and the sampling pipeline is connected with a battery loop or a production line and used for obtaining samples; the integrated detection module comprises a micro-fluidic chip, the micro-fluidic chip is provided with a micro-fluidic detection channel and a shared micro detection pool connected with the micro-fluidic detection channel, and a plurality of micro electrodes for detecting different parameters are integrated in the shared micro detection pool; the fluid control module comprises a multi-path flow path selection valve, an inlet of the multi-path flow path selection valve is respectively connected with a sampling pipeline, a standard solution, a cleaning solution and at least two titrants, and an outlet of the multi-path flow path selection valve is connected with the microfluidic detection channel. The detection parameters are more comprehensive, the stability of long-term operation of the system is ensured, and the reliability of online detection is improved.

Description

Technical Field

[0001] This application relates to the field of vanadium redox flow battery technology, and in particular to a multi-parameter online detection system and method for electrolytes in all vanadium redox flow batteries. Background Technology

[0002] The performance of a vanadium redox flow battery (VRFB) is highly dependent on the valence distribution of vanadium ions in the positive and negative electrode electrolytes and the acidity of the electrolyte. Ideally, the battery capacity is maximized when the overall valence of the electrolyte is 3.5. However, during charge-discharge and long-term operation, due to ion transmembrane migration (permeation) and side reactions (such as V2O ... 5 Factors such as hydrolysis and precipitation of ⁺ can cause an imbalance in the concentration of vanadium ions and the total acidity of the positive and negative electrode electrolytes, which in turn can lead to battery capacity decay, efficiency reduction, and even safety issues.

[0003] Currently, the monitoring of electrolytes mainly faces the following challenges and difficulties: 1. Offline detection is used, but it has its own limitations in terms of latency and disruption. Specifically, offline detection relies on laboratory sampling and analysis, such as ultraviolet spectrophotometry and inductively coupled plasma mass spectrometry (ICP-MS). These methods are cumbersome and time-consuming, cannot reflect the real-time status of the battery during operation or production, and may introduce contamination and errors during sampling.

[0004] 2. Online detection is employed, but existing online detection methods lack reliability. Specifically, traditional online sensors are easily contaminated and prone to crystallization and blockage in complex vanadium electrolyte environments, leading to severe signal drift, extremely short lifespan, frequent manual maintenance and calibration, and difficulty in stable operation in industrial settings.

[0005] 3. Existing detection methods rely on single parameters and lack a systematic approach. Specifically, current technologies typically only measure a single parameter (such as total vanadium concentration or pH), and cannot simultaneously and homogeneously obtain V³⁺ and V⁻. 4 ⁺、V 5 Information on the concentration of ions with multiple valences, such as ⁺ and acidity, is insufficient to comprehensively assess the "health status" of the electrolyte.

[0006] Therefore, overcoming the problems of insufficient reliability and limited detection parameters in existing online detection technologies is a challenge to be solved in this technical field. Summary of the Invention

[0007] To address the aforementioned deficiencies or improvement needs of existing technologies, and to resolve the issues of insufficient reliability and limited detection parameters in current electrolyte monitoring online detection, this application provides a multi-parameter online detection system and method for vanadium redox flow battery electrolytes. By integrating detection modules, it achieves simultaneous online detection of the concentration and acidity of multivalent vanadium ions in the electrolyte, making the detection parameters more comprehensive. Furthermore, a fluid control module automatically handles high-concentration samples, effectively preventing blockage and contamination of pipelines and sensors, ensuring the long-term stability of the system, and improving the reliability of online detection.

[0008] The embodiments of this application adopt the following technical solutions: In a first aspect, this application provides a multi-parameter online detection system for electrolytes in vanadium redox flow batteries, including a sampling pipeline, an integrated detection module, and a fluid control module, wherein: The sampling pipeline is connected to the battery circuit or production line to obtain samples; The integrated detection module includes a microfluidic chip, on which a microfluidic detection channel is provided and a shared micro detection pool connected to the microfluidic detection channel is provided. The shared micro detection pool integrates multiple microelectrodes for detecting different parameters. The fluid control module includes a multi-path selection valve. The inlet of the multi-path selection valve is connected to a sampling pipeline, a standard solution, a cleaning solution, and at least two titrants, respectively. The outlet of the multi-path selection valve is connected to the microfluidic detection channel.

[0009] By adopting the above technical solution, based on multiple microelectrodes integrated within a shared micro-detection cell, the detection of different parameters of a sample can be achieved. The multi-path selection valve of the fluid control module can control the connection and closure between the sampling pipeline, standard solution, cleaning solution, at least two titrants, and the microfluidic detection channel. The standard solution can dilute the sample, the cleaning solution can clean each channel, and different titrants can be used in conjunction with the microelectrodes to detect different parameters of the sample. This solution achieves simultaneous online detection of the concentration and acidity of multivalent vanadium ions in the electrolyte through the integrated detection module, making the detection parameters more comprehensive. The fluid control module automatically handles high-concentration samples, effectively preventing blockage and contamination of pipelines and sensors, ensuring the long-term stability of the system, and improving the reliability of online detection.

[0010] In some embodiments, the integrated detection module includes a potentiometric titration unit and an acid-base titration unit, wherein: The potentiometric titration unit performs potential detection via a microelectrode. During potential detection, the multi-path flow selection valve connects the sample to the first titrant and pumps it into the shared micro-detection cell. The acid-base titration unit performs acid-base detection via a microelectrode. During acid-base detection, the multi-path selection valve connects the sample to the second titrant and pumps it into the shared micro-detection cell. The first titrant is a redox titrant, and the second titrant is an acid-base titrant.

[0011] By adopting the above technical solution, the potentiometric titration unit uses a combination of microelectrodes and redox titrants to detect the potential of the sample, that is, to detect the concentration of vanadium ions in various valence states in the electrolyte; the acid-base titration unit uses a combination of microelectrodes and acid-base titrants to detect the acidity and alkali of the sample; the above solution realizes the simultaneous online detection of the concentration of multiple valence states and acidity in key chemical parameters of vanadium electrolyte, making the detection data more comprehensive and traceable.

[0012] In some embodiments, the fluid control module includes an automatic dilution unit and a self-cleaning unit, wherein: The automatic dilution unit is used to dilute high-concentration samples with standard solutions to adapt to the detection range; during dilution, the multi-path selection valve connects the sample and the standard solution. The self-cleaning unit is used to clean the sampling pipeline, microfluidic detection channel and shared micro detection cell with cleaning fluid; during cleaning, the multi-path selection valve connects the cleaning fluid to the microfluidic detection channel and the sampling pipeline.

[0013] By adopting the above technical solutions, the automatic dilution unit uses standard solution to dilute high-concentration samples, making the samples suitable for the detection range and improving detection accuracy; the self-cleaning unit uses cleaning solution to clean the sampling pipeline, microfluidic detection channel and shared micro detection cell, which can effectively prevent the pipeline and sensor from being blocked and contaminated, and ensure the long-term stability of the system.

[0014] In some embodiments, the system further includes an intelligent calibration module, which includes a standard solution reservoir and a control unit. The control unit periodically or according to triggering conditions controls the standard solution reservoir to inject standard solution into the detection flow path, and automatically corrects the measurement parameters of the integrated detection module by comparing the detection results of the standard solution with the predicted values ​​of the built-in algorithm model. The built-in algorithm model employs a transfer learning algorithm.

[0015] By adopting the above technical solution, the system can periodically or automatically correct the measurement parameters of the integrated detection module according to triggering conditions. The built-in transfer learning algorithm can quickly adapt to different electrolyte systems using a small amount of new data, realizing the leap from passive calibration to active correction, which greatly extends the maintenance cycle, improves the reliability and intelligence of the system, reduces the dependence on manpower, and lowers the operation and maintenance costs.

[0016] In some embodiments, the outlet of the shared micro detection cell is connected to a standard solution regeneration unit, and the outlet of the standard solution regeneration unit is connected to the standard solution storage device; the standard solution regeneration unit recovers vanadium ions from the waste liquid through electrolysis or crystallization, thereby realizing the recycling of the standard solution.

[0017] By adopting the above technical solution, vanadium ions in the waste liquid are recovered by the standard liquid regeneration unit in the multi-parameter online detection system of vanadium redox flow battery electrolyte, realizing the recycling of standard liquid, reducing operating costs, and supporting long-term maintenance-free operation of the system.

[0018] In some embodiments, a data interaction and control module is further included, which is electrically connected to the integrated detection module and the intelligent correction module, and is used for temperature compensation, data storage and remote transmission.

[0019] By adopting the above technical solutions, the data interaction and control module performs temperature compensation on the data from the integrated detection module and the intelligent correction module, which can improve the accuracy of the detection data; it stores the data, which facilitates the subsequent analysis and tracing of historical data; and it enables remote transmission, which can transmit the detection results to the host computer or cloud platform in real time, facilitating remote monitoring and management.

[0020] In some embodiments, the data interaction and control module further includes a fault prediction unit, which predicts sensor lifespan or pipeline blockage risk and issues an early warning based on the long-term drift trend of the detection signal, self-cleaning frequency and pump valve operating status.

[0021] By adopting the above technical solution, the fault prediction unit can predict the sensor lifespan or pipeline blockage risk based on various states of the detection signal, and issue early warnings, which helps to improve the reliability of system operation and reduce the impact of potential faults on detection work.

[0022] In some embodiments, the intelligent correction module is provided with a manual intervention interface, allowing manual correction of model prediction results via a local interface or remote commands.

[0023] By adopting the above technical solutions, the manual intervention interface can promptly address measurement deviations caused by factors such as sensor drift and abnormal samples, further improving the accuracy and reliability of the system's detection, reducing the impact of abnormal situations on the detection results, and enhancing the system's adaptability under complex working conditions.

[0024] Secondly, this application provides a multi-parameter online detection method for vanadium redox flow battery electrolytes, applied to the multi-parameter online detection system for vanadium redox flow battery electrolytes described in the first aspect, comprising: The fluid control module performs initial cleaning, backwashing the microfluidic chip and sampling tubing. Automatically extract electrolyte samples to be tested from battery circuits or production lines; High-concentration samples are quantitatively diluted using a fluid control module to accommodate different detection ranges. Potentiometric titration and acid-base titration can be performed in parallel or sequentially, and microfluidic chips can be used to simultaneously obtain vanadium ion concentration and acidity data for each valence state.

[0025] By adopting the above technical solutions, the fluid control module can perform initial cleaning to backwash the microfluidic chip and sampling pipeline, effectively preventing blockage and contamination of pipelines and sensors, and ensuring the long-term stability of the system. Automatic extraction of electrolyte samples from the battery circuit or production line enables in-situ, real-time, and continuous monitoring of the electrolyte. Quantitative dilution of high-concentration samples by the fluid control module allows the samples to adapt to the detection range, ensuring smooth detection. Parallel or sequential execution of potentiometric titration and acid-base titration, utilizing the microfluidic chip to simultaneously obtain vanadium ion concentration and acidity data at various valence states, enables synchronous online detection of key chemical parameters of vanadium electrolyte, resulting in more comprehensive data and stronger traceability.

[0026] In some embodiments, during potentiometric titration, the superimposed potential signals of multivalent ions are decoupled by analyzing multiple potential inflection points during the titration process, thereby calculating the concentration of multivalent ions.

[0027] By employing the above technical solution, multiple potential inflection points can be analyzed during potentiometric titration, thus decoupling V³⁺ and V. 4 ⁺、V 5 The superimposed potential signal of ⁺ is used to accurately calculate the concentration of multivalent ions in the electrolyte of the vanadium redox flow battery, enabling simultaneous online detection of key chemical parameters of the electrolyte, making the detection data more comprehensive and traceable.

[0028] In summary, this application includes at least the following beneficial technical effects: 1. The microfluidic chip with integrated detection module and shared micro detection cell, together with potentiometric titration unit and acid-base titration unit, realize the synchronous online detection of multivalent ion concentration and acidity of vanadium redox flow battery electrolyte, which solves the problem of single detection parameters in the existing technology and provides more comprehensive data; 2. The automatic dilution unit and self-cleaning unit of the fluid control module can automatically handle high-concentration samples and clean the sampling pipeline and detection cell with cleaning solution to prevent the pipeline and sensor from being blocked and contaminated. This solves the problem of traditional online sensors being easily contaminated and blocked by crystals, and ensures the stability of the system in long-term operation. 3. The intelligent correction module adopts a transfer learning algorithm to periodically or automatically correct the measurement parameters of the integrated detection module according to trigger conditions, which reduces the reliance on manpower, lowers the operation and maintenance costs, and improves the accuracy and reliability of detection. Attached Figure Description

[0029] To more clearly illustrate the technical solutions of the embodiments of this application, the drawings used in the embodiments of this application will be briefly described below. Obviously, the drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0030] Figure 1 A structural block diagram of a multi-parameter online detection system for vanadium redox flow battery electrolyte provided in this application embodiment; Figure 2 The module connection frames provided in the embodiments of this application; Figure 3 A structural block diagram of the standard solution regeneration unit provided in the embodiments of this application; Figure 4 This is a flowchart illustrating a multi-parameter online detection method for electrolyte in a vanadium redox flow battery, provided as an embodiment of this application. Detailed Implementation

[0031] To make the objectives, technical solutions, and advantages of this application clearer, the following detailed description is provided in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative and not intended to limit the scope of this application. Furthermore, the technical features involved in the various embodiments described below can be combined with each other as long as they do not conflict with each other. The application will now be described in detail with reference to the accompanying drawings and embodiments. Example 1

[0032] like Figure 1As shown in Embodiment 1 of this application, a multi-parameter online detection system for vanadium redox flow battery electrolyte is provided, including a sampling pipeline, an integrated detection module, and a fluid control module. The sampling pipeline is connected to the battery circuit or production line for acquiring samples. The integrated detection module includes a microfluidic chip with a microfluidic detection channel and a shared micro-detection cell connected to the microfluidic detection channel. The shared micro-detection cell integrates multiple microelectrodes for detecting different parameters. The fluid control module includes a multi-path selection valve. The inlet of the multi-path selection valve is connected to the sampling pipeline, a standard solution, a cleaning solution, and at least two titrants, respectively. The outlet of the multi-path selection valve is connected to the microfluidic detection channel. The above technical solution, based on multiple microelectrodes integrated within a shared micro-detection cell, enables the detection of different parameters of a sample. The multi-path selection valve of the fluid control module controls the connection and closure between the sampling pipeline, standard solution, cleaning solution, at least two titrants, and the microfluidic detection channel. The standard solution dilutes the sample, the cleaning solution cleans each channel, and different titrants, in conjunction with the microelectrodes, enable the detection of different sample parameters. This solution achieves simultaneous online detection of the concentration and acidity of multivalent vanadium ions in the electrolyte through the integrated detection module, resulting in more comprehensive detection parameters. The fluid control module automatically handles high-concentration samples, effectively preventing blockage and contamination of pipelines and sensors, ensuring the long-term stability of the system, and improving the reliability of online detection. It should be noted that the integrated detection module is not directly installed inside the positive or negative electrode tank, but rather serves as an independent external analysis unit, connected to the battery circuit or production line via the sampling pipeline.

[0033] refer to Figure 2 As shown, in some embodiments, the integrated detection module includes a potentiometric titration unit and an acid-base titration unit, wherein: the potentiometric titration unit performs potential detection via a microelectrode; during potential detection, the multi-path selection valve connects the sample to a first titrant and pumps it into the shared micro-detection cell; the acid-base titration unit performs acid-base detection via a microelectrode; during acid-base detection, the multi-path selection valve connects the sample to a second titrant and pumps it into the shared micro-detection cell; the first titrant is a redox titrant, and the second titrant is an acid-base titrant. Through the above technical solution, the potentiometric titration unit uses a microelectrode and a redox titrant to perform potential detection on the sample, i.e., to detect the concentration of vanadium ions in various valence states in the electrolyte; the acid-base titration unit uses a microelectrode and an acid-base titrant to perform acid-base detection on the sample; the above solution achieves simultaneous online detection of the concentration of multiple valence states and acidity in key chemical parameters of the vanadium electrolyte, making the detection data more comprehensive and traceable.

[0034] It should be noted that the potentiometric titration unit and the acid-base titration unit are functional units. These functions can be integrated using a microfluidic chip for online detection of vanadium ion concentrations and acidity at various valence states in the electrolyte. Specifically, this "integration" is achieved primarily through a "shared flow path + shared detection cell + multifunctional sensor." The core component for the shared fluid path and time-sharing control is a multi-path selection valve (such as a miniature rotary valve or an array of solenoid valves). This valve is part of the fluid control module, but its control logic directly serves the integrated detection module. It has multiple inlets (connecting to samples, standard solutions, first titrant, second titrant, cleaning solution, etc.) and a common outlet connected to a single, shared microfluidic detection channel and detection cell.

[0035] Workflow: Step 1 (Potential Titration): The flow path selection valve connects the "sample" and the "first titrant (e.g., redox titrant)" and pumps them into the shared detection cell in proportion. At this time, the system performs potentiometric titration, and the integrated electrode monitors the change in solution potential.

[0036] Step 2 (rinsing): After completing the potentiometric titration, switch the valve to the "cleaning fluid" inlet to rinse the shared detection cell and flow path.

[0037] Step 3 (Acid-Base Titration): The flow path selection valve connects the "sample" and the "acid-base titrant (e.g., NaOH solution)" and pumps them into the same shared detection cell. At this point, the system performs an acid-base titration. Acidity can be detected in two ways: Method A (potential method): The same set of integrated electrodes is used to monitor the potential transition caused by the change in H⁺ ion concentration during titration (pH potential method), without the need for an additional pH sensor; Method B (integrated pH sensor): A miniature solid-state pH sensor (such as ISFET) is integrated into the shared detection cell to directly read the pH value during acid-base titration.

[0038] Step 4 (Flush Again): Prepare for the next testing cycle.

[0039] For shared detection cells and integrated sensors, the core components are a shared micro-detection cell and integrated multifunctional electrodes. Specifically, a microliter or even nanoliter-sized cavity is fabricated on a microfluidic chip to serve as the detection cell. Microelectrodes are integrated into the bottom or sidewalls of this detection cell using microfabrication techniques (such as photolithography and sputtering).

[0040] Electrode configurations may include: Working electrode (e.g., Pt): used to sense redox couples (e.g., V). 4 ⁺ / V 5 The potential of (V²⁺ / V³⁺); Reference electrode (e.g., Ag / AgCl): provides a stable potential reference; (Optional) Counter electrode: Used if current needs to be applied; (Optional) pH sensing electrode (such as ISFET): Used if acidity detection is performed using method B.

[0041] The ultimate manifestation of the aforementioned "integration": Spatial integration: Two titration reactions occur sequentially within the same physical space (detection cell); Sensor integration: Sensors (potential electrode pairs and / or pH sensors) used to monitor two different chemical reactions are miniaturized and integrated into the same detection cell.

[0042] Integrated flow path: Samples and different reagents are delivered to the detection cell through the same set of microfluidic channels.

[0043] The principles of potentiometric titration and acid-base titration will be further explained below.

[0044] Potentiometric titration: Used to detect the concentration of vanadium ions in various valence states. Principle: A redox titrant of known concentration, such as cerium persulfate (Ce(SO4)2), is continuously added to the electrolyte to be tested. This titrant reacts with vanadium ions in different valence states (V²⁺, V³⁺, V...). 4 ⁺, V 5 (⁺) A sequential redox reaction occurs. Key method: During the reaction, changes in solution potential are monitored in real time using microelectrodes integrated on a microfluidic chip. How to determine the concentration: When vanadium ions of different valence states are titrated and oxidized, characteristic potential inflection points are generated on the titration curve. The amount of titrant consumed at each inflection point is directly proportional to the concentration of vanadium ions of that valence state. Example: Titration of a positive electrode electrolyte (containing V...) 4 ⁺ and V 5 When ⁺), the titration curve will show two inflection points, the first being V. 4 ⁺ is oxidized to V 5 ⁺, The second is the inflection point caused by excess titrant. By calculating the volume of titrant between the two inflection points, V can be calculated. 4 The concentration of ⁺.

[0045] Specifically, the online detection process includes the following steps: Step 1: Automatic Sampling and Preprocessing. Method: The system extracts a trace amount (microliter) of the electrolyte to be tested from the battery circuit using a micropump and valve; Purpose: To obtain a representative sample. If the concentration is too high, the automatic dilution unit will accurately dilute it to the detection linear range.

[0046] Step 2: "Miniaturized Titration" within the Microfluidic Chip. Method: The diluted sample and redox titrant are pumped into the shared detection cell of the microfluidic chip at a precisely controlled flow rate and mixed; simultaneously, monitoring is conducted: within the detection cell, integrated microelectrode pairs (such as platinum electrodes vs. a reference electrode) begin to measure the solution's potential value in real time and at high frequency.

[0047] Step 3: Obtain the "potential-titer volume" curve. Process: As the titrant is continuously added, different vanadium ions are oxidized sequentially, and the potential of the solution changes accordingly; Key data: The system records a complete "potential vs. volume of added titrant (or time)" curve, i.e., the titration curve.

[0048] Curve Interpretation and Concentration Calculation: 1. Identify inflection points: The curve does not rise smoothly, but rather shows obvious "steps" or "inflection points" at specific locations. Each inflection point represents the completion of the reaction of one vanadium ion valence state, and the start of the next reaction.

[0049] 2. Quantitative calculation: The volume of titrant consumed between the two inflection points (ΔV) is directly proportional to the concentration of vanadium ions in the corresponding valence state in the solution.

[0050] Example: In the positive electrode electrolyte (mainly containing V) 4 ⁺ and V 5 In (⁺), the first inflection point corresponds to V. 4 ⁺ is completely oxidized to V 5 ⁺. Therefore, the volume of titrant consumed from the start of titration to the first inflection point can be used to calculate V. 4 The concentration of ⁺. Generally speaking, after the oxidant is added, the order of oxidation states is usually: V²⁺, V³⁺, V 4 ⁺, V 5 ⁺, the concentration of each valence state can be calculated according to this order.

[0051] Acid-base titration: Used to determine total acidity. Principle: A standard alkaline solution of known concentration (e.g., NaOH) is added to another sample of the electrolyte to be tested. Key methods: Integrated electrodes are used to monitor changes in solution potential (because changes in H⁺ ion concentration cause significant potential transitions), or an integrated miniature pH sensor is used to directly measure the pH value until the endpoint is reached. How to determine acidity: A clear acidity titration endpoint will appear on the potential-pH titration curve. The total acid concentration of the electrolyte can be calculated based on the volume of alkaline solution consumed to reach this endpoint.

[0052] Through the above design, a multifunctional integrated detection module was realized, integrating concentration detection based on potentiometric titration and acidity detection based on acid-base titration into one unit, sharing a microfluidic cell and control system, achieving the detection of V³⁺ and V... 4 ⁺、V5 Simultaneous measurement of ⁺, total vanadium and acidity.

[0053] refer to Figure 2 As shown, in some embodiments, the fluid control module includes an automatic dilution unit and a self-cleaning unit, wherein: the automatic dilution unit is used to dilute high-concentration samples with standard solutions to adapt to the detection range; during dilution, the multi-path selection valve connects the sample to the standard solution; the self-cleaning unit is used to clean the sampling pipeline, microfluidic detection channel, and shared micro-detection cell with cleaning solution; during cleaning, the multi-path selection valve connects the cleaning solution to the microfluidic detection channel and the sampling pipeline. Through the above technical solution, the automatic dilution unit uses standard solutions to dilute high-concentration samples, adapting the samples to the detection range and improving detection accuracy; the self-cleaning unit uses cleaning solution to clean the sampling pipeline, microfluidic detection channel, and shared micro-detection cell, effectively preventing blockage and contamination of pipelines and sensors, ensuring the long-term stability of the system. It should be noted that the self-cleaning unit can include both cleaning and backwashing methods, enabling one-button automatic cleaning of the sampling pipeline and detection cell according to a preset program or command.

[0054] Through the above design, an active self-maintaining fluid system was realized. A fluid control module was designed that includes automatic dilution, backwashing, and programmed self-cleaning. The system can automatically handle high-concentration samples and effectively prevent blockage and contamination of pipelines and sensors through regular backwashing and chemical cleaning, thus ensuring long-term operational stability.

[0055] refer to Figure 2As shown, in some embodiments, an intelligent calibration module is also included. This module comprises a standard solution reservoir and a control unit. The control unit is configured to periodically or according to triggering conditions inject standard solution into the detection flow path from the standard solution reservoir, and automatically correct the measurement parameters of the integrated detection module by comparing the detection results of the standard solution with the predicted values ​​of the built-in algorithm model. The built-in algorithm model employs a transfer learning algorithm, enabling rapid adaptation to different electrolyte systems using a small amount of new data. Through this technical solution, the system can periodically or automatically correct the measurement parameters of the integrated detection module according to triggering conditions. The built-in transfer learning algorithm can rapidly adapt to different electrolyte systems using a small amount of new data, achieving a leap from passive calibration to active calibration, greatly extending the maintenance cycle, improving the system's reliability and intelligence, reducing reliance on manpower, and lowering operation and maintenance costs. Furthermore, the intelligent calibration module is equipped with a manual intervention interface, allowing manual correction of the model's predicted results via a local interface or remote commands to address abnormal operating conditions. The manual intervention interface can promptly address measurement deviations caused by factors such as sensor drift and abnormal samples, further improving the accuracy and reliability of the system's detection, reducing the impact of abnormal situations on the detection results, and enhancing the system's adaptability under complex working conditions.

[0056] In the above process, the triggering conditions for the control unit include: Signal drift exceeding threshold: The control unit monitors the output signal of the integrated detection module (such as baseline potential and sensor internal resistance) in real time. When the signal drift exceeds the preset threshold, correction is triggered immediately. Sudden data changes or deviations from reasonable range: A drastic and illogical jump in a single measurement result compared to historical data or theoretical values ​​may indicate a sensor malfunction or severe contamination, triggering calibration for verification and correction.

[0057] In the above process, the input to the transfer learning algorithm is the entire titration curve. It is mainly used to compensate for potential drift caused by electrode aging, or to correct titration endpoint identification errors caused by the presence of unknown impurity ions (such as iron and chromium) in new batches of electrolyte. Through the transfer learning algorithm, the basic model trained on the standard solution is fine-tuned using a small amount of data from the new batch of electrolyte collected on-site, allowing it to quickly adapt to the matrix effects of the new electrolyte, without requiring a complete remodeling that would take several days, as is done with traditional methods.

[0058] Through the above design, model-based intelligent calibration technology was realized. An intelligent calibration module was introduced, which not only performs routine calibration with standard solutions periodically, but more importantly, its built-in adaptive algorithm model can learn the drift characteristics of the sensor and combine historical data to predict and compensate for future measurements. This realizes the leap from "passive calibration" to "active calibration" and greatly extends the maintenance cycle.

[0059] refer to Figure 2 As shown, in some embodiments, the outlet of the shared micro-detection cell is connected to a standard solution regeneration unit, and the outlet of the standard solution regeneration unit is connected to the standard solution storage tank. The standard solution regeneration unit recovers vanadium ions from the waste liquid through electrolysis or crystallization, realizing the recycling of the standard solution and reducing consumable costs. Through the above technical solution, in the multi-parameter online detection system of vanadium redox flow battery electrolyte, the standard solution regeneration unit is used to recover vanadium ions from the waste liquid, realizing the recycling of the standard solution, reducing operating costs, and supporting long-term maintenance-free operation of the system.

[0060] refer to Figure 3 As shown, in some embodiments, the standard solution regeneration unit includes a core processing module, a post-processing module, and a regenerated standard solution storage tank. The core processing module includes an electrolytic cell or crystallizer for recovering vanadium ions from the waste liquid through electrolysis or crystallization. The post-processing module purifies, concentrates, and redissolves the waste liquid processed by the core processing module to form a regenerated standard solution. The regenerated standard solution storage tank is used to temporarily store the regenerated standard solution and is connected to a standard solution storage device to transfer the regenerated standard solution to the standard solution storage device when needed. The core processing module can be connected to the outlet of a shared micro-detection cell through a waste liquid pool to collect all waste liquid and transfer it to the core processing module for processing when needed.

[0061] refer to Figure 2 As shown, in some embodiments, a data interaction and control module is also included. This module is electrically connected to the integrated detection module and the intelligent correction module, and is used to receive detection data and perform temperature compensation, data storage, and remote transmission. Through the above technical solution, the data interaction and control module performs temperature compensation on the data from the integrated detection module and the intelligent correction module, which can improve the accuracy of the detection data; it stores the data, facilitating subsequent analysis and tracing of historical data; and it enables remote transmission, allowing the detection results to be transmitted to a host computer or cloud platform in real time, facilitating remote monitoring and management.

[0062] Furthermore, the data interaction and control module also includes a fault prediction unit. This unit predicts sensor lifespan or pipeline blockage risk and issues early warnings based on the long-term drift trend of the detection signal, self-cleaning frequency, and pump / valve operating status. The fault prediction unit can predict sensor lifespan or pipeline blockage risk based on various states of the detection signal, issuing early warnings in advance, which helps improve the reliability of system operation and reduce the impact of potential faults on detection work.

[0063] Specifically, for the long-term drift trend of the detection signal, the data source is the integrated detection module (such as the baseline potential of the electrode and the baseline light intensity of the optical unit); the acquisition method is to record the "correction amount" or "offset amount" required to achieve the same concentration reading each time a standard solution is used for calibration; for example, record the slow change value of the electrode potential over time. For the self-cleaning frequency and effect, the data source is the execution record of the fluid control module; the acquisition method is to record the trigger frequency of the self-cleaning operation. If the system needs to be cleaned more and more frequently to maintain stability, this is itself a strong degradation signal; record the degree of signal recovery after cleaning. If the signal cannot be restored to the initial cleanliness level after cleaning, it indicates permanent contamination or sensor aging. For the pump and valve operating status, the data source is: the built-in sensors or drive circuits of the pump and valve; the acquisition method is: operating current / power consumption, monitoring the operating current of the micro pump. An increase in current may mean increased mechanical friction (such as bearing wear) or increased fluid resistance (pipeline blockage); an abnormal decrease in current may mean internal leakage of the pump; response time / sealing, recording the time from receiving the command to the valve being fully opened / closed. A longer time may mean that the valve core is stuck. By monitoring the pressure change downstream in the closed state, it can be determined whether there is internal leakage of the valve.

[0064] Through the above design, an integrated hardware and software data engine was realized. The data interaction and control module is not only a data relay station, but also has edge computing capabilities. It integrates a real-time temperature compensation algorithm and can decouple the contribution of vanadium ions of various valence states from complex potential titration curves through advanced signal processing technology (such as chemometrics algorithms), thereby improving the accuracy of analysis and anti-interference ability. At the same time, it has a fault early warning function, which can report potential risks of the system in advance.

[0065] In some implementations, the system supports replaceable titration kits, allowing for the expansion of the detection targets to include other metal ions, including iron, chromium, or manganese ions, by replacing different kits. Specifically, the titration kit can be located at the bottom of the device or anywhere else, as long as it can connect to a multi-path rotary valve. The kit is removable and replaceable, and the specific titration reagents can be prepared and calibrated in the laboratory or purchased as standard titration solutions.

[0066] In some implementations, the system's sampling pipeline is connected in parallel or in series with the stack pipeline of the vanadium redox flow battery or the reaction pipeline of the electrolyte production line. The sampling tube extends into the pipeline (the electrolyte production line's electrolyte conveying pipeline or any pipeline with electrolyte flow) through a 1 / 4-28 UNF threaded connector to achieve in-situ online sampling.

[0067] In some implementations, the detection data transmitted by the data interaction and control module directly interlocks and controls the raw material injection valve in the electrolyte production process or the circulation pump speed in the battery operation process, forming a closed-loop control system.

[0068] In summary, the multi-parameter online detection system for vanadium redox flow battery electrolytes provided in this application includes: an integrated detection module that integrates a potentiometric titration unit and an acid-base titration unit using microfluidic chip technology for online detection of the concentration and acidity of vanadium ions in various valence states in the electrolyte; a fluid control module that includes an automatic dilution unit and a self-cleaning unit, and employs an energy-saving micro-pump valve to reduce power consumption; an intelligent correction module that incorporates a transfer learning algorithm to quickly adapt to different electrolyte systems using a small amount of new data, and adds a manual intervention interface to allow users to manually correct abnormal model predictions; and a data interaction and control module that integrates temperature compensation, data storage, and remote transmission. This application achieves full-parameter, high-precision, adaptive intelligent sensing and control of the electrolyte state, improving reliability, economy, and industrial field adaptability. Example 2

[0069] Based on the multi-parameter online detection system for vanadium redox flow battery electrolyte provided in Example 1, this Example 2 provides a multi-parameter online detection method for vanadium redox flow battery electrolyte, applied to the multi-parameter online detection system for vanadium redox flow battery electrolyte described in Example 1. The method includes: Step 101: The fluid control module performs initial cleaning, backwashing the microfluidic chip and sampling tubing. In this step, after the system starts up, the self-cleaning unit of the fluid control module performs initial cleaning, backwashing the microfluidic chip and sampling tubing.

[0070] Step 102: Automatically extract the electrolyte sample to be tested from the battery circuit or production line.

[0071] Step 103: Quantitatively dilute the high-concentration sample using the fluid control module to adapt to the detection range. In this step, the dilution operation is performed using the automatic dilution unit of the fluid control module.

[0072] Step 104: Perform potentiometric titration and acid-base titration in parallel or sequentially, and use a microfluidic chip to simultaneously obtain vanadium ion concentration and acidity data for each valence state.

[0073] Through the above technical solutions, the fluid control module performs initial cleaning to backwash the microfluidic chip and sampling pipeline, effectively preventing blockage and contamination of pipelines and sensors, and ensuring the long-term stability of the system. It automatically extracts electrolyte samples from the battery circuit or production line, enabling in-situ, real-time, and continuous monitoring of the electrolyte. Quantitative dilution of high-concentration samples by the fluid control module allows the samples to adapt to the detection range, ensuring smooth detection. Parallel or sequential potentiometric titration and acid-base titration are performed, simultaneously obtaining vanadium ion concentration and acidity data at various valence states using the microfluidic chip. This enables synchronous online detection of key chemical parameters of the vanadium electrolyte, resulting in more comprehensive data and stronger traceability.

[0074] Furthermore, based on steps 101-104, subsequent steps can be performed through the data interaction and control module and the intelligent correction module. For example: Step 105: The data interaction and control module receives the raw data, integrates the temperature sensor signal for compensation calculation, and obtains the final detection result.

[0075] Step 106: Display, store, and upload the final results locally in real time.

[0076] Step 107: The intelligent calibration module executes an automatic calibration process according to a preset cycle, updating model parameters using a transfer learning algorithm. Specifically, the intelligent calibration module uses a transfer learning algorithm to quickly adapt to different electrolyte systems based on a small amount of new data, including electrolytes with different vanadium concentrations, acidities, or additive formulations.

[0077] Step 108: Based on the final result, generate control commands to interlock and adjust electrolyte production or battery operating parameters.

[0078] In some implementations, during the potentiometric titration in step 104, V³⁺ and V are decoupled by analyzing multiple potential inflection points during the titration process. 4 ⁺、V 5 The superimposed potential signal of ⁺ is used to calculate the concentration of multivalent ions. This method accurately calculates the concentration of multivalent ions in the electrolyte of a vanadium redox flow battery, enabling simultaneous online detection of key chemical parameters of the electrolyte, resulting in more comprehensive and traceable data.

[0079] In some implementations, the method provided in this embodiment is applied to the continuous production process of vanadium electrolyte, replacing the traditional batch reactor production mode, and realizing "just-in-time" production by controlling the addition of raw materials and the reaction process in real time based on online detection results.

[0080] In some implementations, the system also includes receiving manual correction commands from users via a human intervention interface to adjust model predictions and correct measurement biases caused by sensor drift or abnormal samples.

[0081] In some implementations, the system also includes changing the titration reagent pack to suit different detection targets, including using EDTA titrant to detect iron ions, thus expanding the application of the system to hybrid flow battery systems.

[0082] In some embodiments, the waste liquid is further subjected to electrolysis or crystallization treatment through a standard solution regeneration unit to recover vanadium ions and regenerate the standard solution, thereby reducing the consumption of external standard solutions and the cost of waste liquid treatment.

[0083] In summary, compared with the prior art, this application has the following significant advantages: 1. Comprehensive and accurate: For the first time, multiple key chemical parameters (multi-valence concentration + acidity) of vanadium electrolyte are simultaneously detected online on a single device, resulting in more comprehensive data and stronger traceability.

[0084] 2. High reliability and long lifespan: The unique self-cleaning and backwashing design, combined with intelligent calibration algorithms, completely solves the problem of the sensor's "delicacy" under harsh working conditions, increasing the mean time between failures (MTBF) to thousands of hours and extending the maintenance cycle from weeks to months.

[0085] 3. True intelligence: It has self-correction, self-diagnosis and even adaptive learning capabilities, reducing reliance on human resources and lowering operation and maintenance costs.

[0086] 4. Plug and play and easy integration: The modular and compact design facilitates installation and integration into existing battery systems or production lines, supports remote data transmission and closed-loop control, and provides a key technological foundation for building smart energy storage power stations and smart factories.

[0087] 5. Promote the innovation of production mode: The application of this application can realize the continuous production of electrolyte, which helps to reduce the equipment footprint, improve production efficiency, reduce energy consumption and product batch differences.

[0088] The above description is merely a preferred embodiment of this application and is not intended to limit this application. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of this application should be included within the protection scope of this application.

Claims

1. A multi-parameter online detection system for electrolyte in vanadium redox flow batteries, characterized in that, This includes sampling pipelines, an integrated detection module, and a fluid control module, among which: The sampling pipeline is connected to the battery circuit or production line to obtain samples; The integrated detection module includes a microfluidic chip, on which a microfluidic detection channel is provided and a shared micro detection pool connected to the microfluidic detection channel is provided. The shared micro detection pool integrates multiple microelectrodes for detecting different parameters. The fluid control module includes a multi-path selection valve. The inlet of the multi-path selection valve is connected to a sampling pipeline, a standard solution, a cleaning solution, and at least two titrants, respectively. The outlet of the multi-path selection valve is connected to the microfluidic detection channel.

2. The multi-parameter online detection system for vanadium redox flow battery electrolyte according to claim 1, characterized in that, The integrated detection module includes a potentiometric titration unit and an acid-base titration unit, wherein: The potentiometric titration unit performs potential detection via a microelectrode. During potential detection, the multi-path flow selection valve connects the sample to the first titrant and pumps it into the shared micro-detection cell. The acid-base titration unit performs acid-base detection via a microelectrode. During acid-base detection, the multi-path selection valve connects the sample to the second titrant and pumps it into the shared micro-detection cell. The first titrant is a redox titrant, and the second titrant is an acid-base titrant.

3. The multi-parameter online detection system for vanadium redox flow battery electrolyte according to claim 1, characterized in that, The fluid control module includes an automatic dilution unit and a self-cleaning unit, wherein: The automatic dilution unit is used to dilute high-concentration samples with standard solutions to adapt to the detection range; during dilution, the multi-path selection valve connects the sample and the standard solution. The self-cleaning unit is used to clean the sampling pipeline, microfluidic detection channel and shared micro detection cell with cleaning fluid; during cleaning, the multi-path selection valve connects the cleaning fluid to the microfluidic detection channel and the sampling pipeline.

4. The multi-parameter online detection system for vanadium redox flow battery electrolyte according to claim 1, characterized in that, It also includes an intelligent calibration module, which includes a standard solution storage unit and a control unit. The control unit periodically or according to triggering conditions controls the standard solution storage unit to inject standard solution into the detection flow path, and automatically corrects the measurement parameters of the integrated detection module based on the detection results of the standard solution and the predicted values ​​of the built-in algorithm model. The built-in algorithm model adopts a transfer learning algorithm.

5. The multi-parameter online detection system for vanadium redox flow battery electrolyte according to claim 4, characterized in that, The common micro detection cell outlet is connected to a standard solution regeneration unit, and the outlet of the standard solution regeneration unit is connected to the standard solution storage container; the standard solution regeneration unit recovers vanadium ions from the waste liquid through electrolysis or crystallization, thereby realizing the recycling of the standard solution.

6. The multi-parameter online detection system for vanadium redox flow battery electrolyte according to claim 4, characterized in that, It also includes a data interaction and control module, which is electrically connected to the integrated detection module and the intelligent correction module, and is used for temperature compensation, data storage and remote transmission.

7. The multi-parameter online detection system for vanadium redox flow battery electrolyte according to claim 6, characterized in that, The data interaction and control module also includes a fault prediction unit, which predicts the sensor lifespan or pipeline blockage risk and issues an early warning based on the long-term drift trend of the detection signal, the self-cleaning frequency, and the pump and valve operating status.

8. The multi-parameter online detection system for vanadium redox flow battery electrolyte according to claim 4, characterized in that, The intelligent correction module is equipped with a manual intervention interface, allowing manual correction of model prediction results via a local interface or remote commands.

9. A method for online detection of multiple parameters for vanadium redox flow battery electrolyte, applied to the online detection system for multiple parameters for vanadium redox flow battery electrolyte as described in any one of claims 1-8, characterized in that, include: The fluid control module performs initial cleaning, backwashing the microfluidic chip and sampling tubing. Automatically extract electrolyte samples to be tested from battery circuits or production lines; High-concentration samples are quantitatively diluted using a fluid control module to accommodate different detection ranges. Potentiometric titration and acid-base titration can be performed in parallel or sequentially, and microfluidic chips can be used to simultaneously obtain vanadium ion concentration and acidity data for each valence state.

10. The method for online detection of multiple parameters of electrolyte in a vanadium redox flow battery according to claim 9, characterized in that, When performing potentiometric titration, the superimposed potential signals of multivalent ions are decoupled by analyzing multiple potential inflection points during the titration process, and then the concentration of multivalent ions is calculated.

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