Flow battery testing device and method

Abstract

The invention provides a flow battery testing device and method.The method comprises the steps that monitoring parameters and protection parameters of a flow battery to be tested are set, and the monitoring parameters and the protection parameters comprise at least one of voltage, current, power, temperature and SOC; based on the requirements of test items, the test process and test parameters of the flow battery are configured through a test configuration file or manual setting, and the test process comprises at least one of the following items: standing, single charging / discharging, multiple charging / discharging, and cyclic charging / discharging. The test parameters comprise at least one of a charging voltage, a discharging voltage, a charging current, a discharging current, a charging power, a discharging power, a charging time, a discharging time, a charging termination voltage, a discharging termination voltage, a charging termination voltage characteristic value and a discharging termination voltage characteristic value; and carrying out a charging and / or discharging test on the flow battery based on the configured test flow and test parameters.

Description

Technical Field

[0001] The present disclosure relates to the technical field of electrochemical energy storage, and in particular to a flow battery testing device and method. Background Art

[0002] In recent years, flow batteries have been increasingly used in the field of large-scale, long-duration power storage due to their long cycle life, high safety, and environmental friendliness. Summary of the invention

[0003] According to one aspect of the present disclosure, a flow battery testing method is proposed, which may include: setting monitoring parameters and protection parameters of the flow battery to be tested, wherein the monitoring parameters and protection parameters include at least one of the following: voltage, current, power, temperature, and SOC; configuring the test process and test parameters of the flow battery through a test configuration file or manual settings based on the requirements of the test item, wherein the test process includes at least one of the following: static, single charge / discharge, multiple charge / discharge, and cyclic charge / discharge, and the test parameters include at least one of the charging voltage, the discharging voltage, the charging current, the discharging current, the charging power, the discharging power, the charging time, the discharging time, the charging termination voltage, the discharging termination voltage, the charging termination voltage characteristic value, and the discharging termination voltage characteristic value; and performing charging and / or discharging tests on the flow battery based on the configured test process and test parameters.

[0004] Optionally, the above method may also include: switching between a first operating mode and a second operating mode, wherein in the first operating mode, electric energy from the AC power grid is provided to the flow battery to charge the flow battery, and in the second operating mode, electric energy from the flow battery is fed back to the AC power grid to discharge the flow battery; wherein at least one of the first operating mode and the second operating mode includes at least one of a constant current, a constant voltage or a constant power mode.

[0005] Optionally, the above method may also include: collecting and displaying in real time the operating parameters of at least one of the flow battery stack, electrolyte, circulation system, and temperature control system during the test; wherein the operating parameters include at least one of the following: the current and voltage of the flow battery stack, the temperature of the electrolyte flowing into the flow battery stack, the temperature of the electrolyte flowing out of the flow battery stack, the flow rate of the electrolyte flowing into the flow battery stack, the flow rate of the electrolyte flowing out of the flow battery stack, the pressure of the electrolyte flowing into the flow battery stack, the pressure of the electrolyte flowing out of the flow battery stack, the liquid level status of the storage tank for storing the electrolyte, the valve status of the pipeline for electrolyte circulation, and the valve status of the pipeline for electrolyte cooling.

[0006] Optionally, the above method may also include: based on the collected operating parameters of at least one of the flow battery stack, electrolyte, circulation system, and temperature control system, generating and outputting at least one of the following control signals: a control signal for the valve opening of the pipeline for electrolyte circulation, a control signal for the valve opening of the pipeline for electrolyte cooling, a control signal for starting and stopping the liquid pump of the pipeline for electrolyte circulation, a control signal for starting and stopping the pump of the pipeline for electrolyte cooling, and a sound / light alarm control signal.

[0007] Optionally, the above method may also include: generating an experimental test report based on the collected operating parameters of at least one of the flow battery stack, electrolyte, circulation system, and temperature control system; wherein the experimental test report includes at least one of the following data or charts: rated discharge energy, maximum discharge energy, rated charging power, rated discharge power, rated energy efficiency, energy retention rate, voltage efficiency, coulombic efficiency, charging characteristic curve, and discharge characteristic curve of the flow battery.

[0008] Optionally, the above method may also include: calculating the rated discharge energy, maximum discharge energy, rated charging power, rated discharge power, rated energy efficiency, energy retention rate, voltage efficiency, and coulombic efficiency of the liquid flow battery based on the current signal and voltage signal of the liquid flow battery collected during multiple cycles of charging / discharging in constant power mode.

[0009] Optionally, the utilization rate of the electrolyte and the utilization rate of the positive electrode active material may also be calculated based on relevant theoretical data of the battery stack.

[0010] According to another aspect of the present disclosure, a liquid flow battery testing device is also proposed, including: a control module for implementing the above method; and a bidirectional conversion module connected to the liquid flow battery and the AC power grid to charge and / or discharge the liquid flow battery.

[0011] Optionally, the above-mentioned liquid flow battery testing device may also include: an analog quantity input module, which includes at least one of the following analog quantity input interfaces: an input interface for the collected current signal of the liquid flow battery, an input interface for the collected voltage signal of the liquid flow battery, an input interface for the collected temperature signal of the electrolyte flowing into the liquid flow battery stack, an input interface for the collected temperature signal of the electrolyte flowing out of the liquid flow battery stack, an input interface for the collected flow signal of the electrolyte flowing into the liquid flow battery stack, an input interface for the collected flow signal of the electrolyte flowing out of the liquid flow battery stack, an input interface for the collected pressure signal of the electrolyte flowing into the liquid flow battery stack, and an input interface for the collected pressure signal of the electrolyte flowing out of the liquid flow battery stack.

[0012] Optionally, the above-mentioned liquid flow battery testing device may also include: an analog output module, which includes at least one of the following analog output interfaces: a control signal output interface for the valve opening of the pipeline for electrolyte circulation, and a control signal output interface for the valve opening of the pipeline for electrolyte cooling.

[0013] Optionally, the above-mentioned liquid flow battery testing device may also include: a switch quantity input module, which includes at least one of the following switch quantity input interfaces: an input interface for collecting liquid level status signals of a liquid storage tank for storing electrolyte, an input interface for collecting valve status signals of pipelines for electrolyte circulation, and an input interface for collecting valve status signals of pipelines for electrolyte cooling.

[0014] Optionally, the above-mentioned liquid flow battery testing device may also include: a switch output module, which includes at least one of the following switch output interfaces: a start / stop control signal output interface of a liquid pump in a pipeline for electrolyte circulation, a start / stop control signal output interface of a pump in a pipeline for electrolyte cooling, and an audio / visual alarm control signal output interface.

[0015] Optionally, the above-mentioned flow battery testing device may further include a human-machine interface module, wherein the human-machine interface module includes at least one of the following: a display / touch screen, a keyboard, and a mouse. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] In order to more clearly illustrate the technical solutions in the embodiments of the present disclosure, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present disclosure. For ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work.

[0017] Figure 1A-1B The main structure of the liquid flow battery system according to the embodiment of the present disclosure is schematically shown;

[0018] Figure 2A-2B The overall architecture and specific structure of the flow battery energy storage system according to the embodiment of the present disclosure are schematically shown respectively;

[0019] Figure 3 is a block diagram schematically showing a flow battery testing device according to an embodiment of the present disclosure;

[0020] Figure 4 It is a schematic assembly structure diagram of a flow battery testing device according to an embodiment of the present disclosure.

[0021] Figure 5-Figure 8 The flowchart of the flow battery testing method according to the embodiment of the present disclosure is schematically shown.

[0022] Fig. 9 The display screen of the human-machine interface of the flow battery testing device according to the embodiment of the present disclosure is shown.

[0023] Figures 10A-10F The relevant waveform curves obtained during the testing of a flow battery by the flow battery testing device and method according to the embodiments of the present disclosure are shown. DETAILED DESCRIPTION

[0024] The detailed description set forth below in conjunction with the accompanying drawings is intended as a description of various configurations and is not intended to represent the only configurations in which the concepts described herein may be practiced. The detailed description includes specific details in order to provide a thorough understanding of the various concepts. However, it will be apparent to those skilled in the art that these concepts may be practiced without these specific details.

[0025] Furthermore, in the drawings, for clarity of illustration, dimensions may be exaggerated and not drawn to scale. Throughout the drawings, like reference numerals generally refer to like elements.

[0026] Liquid flow batteries are generally composed of multiple battery cells stacked together. A single stack or multiple stacks are equipped with electrolyte, circulation system, temperature control system, energy storage inverter, battery management system, power distribution device, fire protection device and other components to form a liquid flow battery energy storage system. The stack is the key core component of the liquid flow battery energy storage system. When the electrolyte flows through the stack, the electrochemical reaction of charging and discharging is realized. The parameters of the circulation system such as flow, pressure, and temperature have an important influence on the performance of the stack.

[0027] Figure 1A The main structure of a flow battery system according to an embodiment of the present disclosure is schematically shown. Figure 1A As shown in FIG. 1 , the flow battery system includes a positive electrode 4 and a negative electrode 6 disposed in a housing 3 of a flow battery stack, and a separator 5 between the positive electrode 4 and the negative electrode 6. As described above, an electrolyte for electrochemical reaction needs to be provided to the stack to realize the charge and discharge of the flow battery. Figure 1A , a circulation system for providing electrolyte circulation for the positive electrode 4 and the negative electrode 6 of the battery stack is shown. Figure 1A As shown, the electrolyte circulation system of the positive electrode 4 includes a positive electrode electrolyte storage device 1, a pipeline 2 and a positive electrode liquid pump 9, while the electrolyte circulation system of the negative electrode 6 includes a negative electrode electrolyte storage device 7, a pipeline 8 and a negative electrode liquid pump 10.

[0028] Figure 1B Another main structure of a flow battery system according to an embodiment of the present disclosure is schematically shown; Figure 1BIn the structure shown, the positive electrode 4 and the negative electrode 6 can share a set of electrolyte circulation system, and the electrolyte circulation system includes: an electrolyte storage device 1, a pipeline 2 and a liquid pump 7.

[0029] Despite the combination Figure 1A and 1B The main structure of the flow battery system according to the embodiment of the present disclosure is described, however, it should be understood that the above structure is only an example for describing the principle of the present disclosure.

[0030] Figure 2A Schematically shows the overall architecture of the flow battery energy storage system according to an embodiment of the present disclosure. As an example, Figure 2A As shown, the system includes a flow battery stack 200, an electrolyte circulation system 210, an electrolyte temperature control system 220, and a signal monitoring system 230. Among them, the electrolyte circulation system 210 can provide electrolyte to the flow battery stack 200 so as to perform electrochemical reactions at the positive / negative electrodes of the stack, thereby realizing the conversion between electrical energy and chemical energy, and completing the charging and / or discharging of the flow battery. Since the flow battery generates a certain amount of heat during the charging and discharging process, this heat mainly comes from the inherent internal resistance and polarization effect, and high temperature will cause the battery performance to decline and even cause safety problems; for example, high temperature will cause the battery performance to decline, such as high temperature will increase the internal resistance of the battery and reduce the charging and discharging efficiency of the battery; and high temperature will also cause material deformation and aging, such as high temperature will accelerate the corrosion and aging of the electrode material and shorten the service life of the battery. To this end, the liquid flow battery energy storage system according to the embodiment of the present disclosure also includes an electrolyte temperature control system 220, which is used to cool the electrolyte so as to control the battery to be at an optimal operating temperature and ensure charging and discharging efficiency and operational safety; in addition, the liquid flow battery energy storage system according to the present disclosure also includes a signal monitoring system 230, which can collect in real time various parameters of the liquid flow battery stack 200, the electrolyte circulation system 210, and the electrolyte temperature control system 220, such as the voltage and current of the liquid flow battery, the temperature, pressure, flow rate of the electrolyte in the electrolyte circulation system, the liquid level of the liquid storage device, the valve state of the pipeline in the electrolyte circulation system 210, the valve state of the pipeline in the electrolyte temperature control system 220, etc., so as to control the liquid flow battery stack 200, the electrolyte circulation system 210 and the electrolyte temperature control system 220, and realize safe and efficient operation of the liquid flow battery energy storage system.

[0031] Figure 2B The specific structure of the liquid flow battery energy storage system according to the embodiment of the present disclosure is schematically shown. Figure 2BAs shown, the electrolyte circulation system mainly includes a liquid storage device 2110 (such as a liquid storage tank), a liquid pump 2120, a valve 2130 and a circulation pipeline 2140; wherein the liquid pump 2120 pumps the electrolyte from the liquid storage device 2110 to the battery stack via the circulation pipeline 2140 to perform an electrochemical reaction with the positive electrode / negative electrode of the battery stack, and allows the electrolyte to circulate between the liquid storage device and the battery stack; by controlling the opening of the valve 2130 on the circulation pipeline 2140, the flow rate of the electrolyte provided to the battery stack can be controlled; the electrolyte temperature control system mainly includes a refrigerator 2210, a heat exchanger (such as a heat exchange plate) 2 220, valve 2230 and circulation pipeline 2240; wherein, the electrolyte can be cooled by heat exchanger 2220 to reduce the temperature of the electrolyte, and a liquid for cooling, such as cooling water, is generated by refrigerator 2210, and the cooling water is transported to heat exchanger 2220 via circulation pipeline 2240, thereby exchanging heat with the hot fluid (such as electrolyte) in the electrolyte circulation system, and then the heat is taken away to achieve cooling of the electrolyte; by controlling the opening of valve 2230 on circulation pipeline 2240, the flow rate of cooling liquid provided to the heat exchanger can be controlled, thereby controlling the heat exchange rate.

[0032] As described above, various operating parameters in the flow battery energy storage system can be collected / monitored in real time or periodically to control the battery stack, electrolyte circulation system and electrolyte temperature control system to achieve safe and efficient operation of the flow battery energy storage system. Figure 2B It is further shown that, for example, the liquid level of the liquid storage device, the temperature, pressure, flow rate and other parameters of the electrolyte in the electrolyte circulation pipeline, including the temperature, pressure, flow rate and other parameters of the electrolyte flowing into the liquid flow battery stack, and the temperature, pressure, flow rate and other parameters of the electrolyte flowing out of the liquid flow battery stack can be collected; the operating parameters of the relevant battery stack can also be collected, for example, the voltage, current, temperature and other parameters of the battery stack.

[0033] By analyzing the various operating parameters in the collected / monitored flow battery energy storage system, corresponding control can be performed, for example, increasing the opening of the valve on the circulation pipeline of the electrolyte circulation system, increasing the power of the liquid pump on the circulation pipeline, so as to increase the circulation volume of the electrolyte; for example, the opening of the valve on the circulation pipeline of the electrolyte temperature control system can be increased, and / or the refrigeration power of the refrigerator can be increased, so as to increase the heat exchange rate of the coolant used for heat exchange.

[0034] In the development and production of battery stacks and supporting circulation systems, suitable testing equipment is needed to test and verify their performance. At present, general instruments and equipment are generally used to test the performance parameters of flow batteries separately. There is still a lack of complete sets of testing equipment for flow batteries. When the complete sets of testing equipment used for traditional batteries such as lithium batteries, lead-acid batteries, and lead-carbon batteries are used for flow battery testing, there are problems such as difficulty in adapting electrical parameters, inability to synchronously complete the detection of circulation system signals, and low testing efficiency.

[0035] Therefore, the embodiments of the present disclosure propose a liquid flow battery testing device and method, which can realize efficient and accurate testing of various parameters and performances of liquid flow battery stacks and their supporting circulation systems, and provide data support for improving the research and development and production quality of liquid flow battery stacks and their supporting circulation systems.

[0036] Figure 3 A flow battery testing device 300 according to an embodiment of the present disclosure is schematically shown.

[0037] like Figure 3 As shown, the liquid flow battery testing device 300 proposed in the present disclosure includes: a bidirectional conversion module 310, connected to the liquid flow battery and the AC power grid, to charge and / or discharge the liquid flow battery, wherein in a first operating mode, the liquid flow battery is charged with electric energy from the AC power grid, and in a second operating mode, the liquid flow battery is discharged to feed the electric energy from the liquid flow battery back to the AC power grid; and a control module 320, connected to the bidirectional conversion module, to control the bidirectional conversion module to operate in the first operating mode and / or the second operating mode, wherein the first operating mode includes at least one of the following: constant current charging, constant voltage charging, and constant power charging; the second operating mode includes at least one of the following: constant current discharging, constant voltage discharging, and constant power discharging.

[0038] Alternatively, if Figure 3 As shown, in the above-mentioned liquid flow battery testing device, it also includes an analog quantity input module 330, and the analog quantity input module includes at least one of the following analog quantity input interfaces: an input interface for the collected current signal of the liquid flow battery, an input interface for the collected voltage signal of the liquid flow battery, an input interface for the collected temperature signal of the electrolyte flowing into the liquid flow battery stack, an input interface for the collected temperature signal of the electrolyte flowing out of the liquid flow battery stack, an input interface for the collected flow signal of the electrolyte flowing into the liquid flow battery stack, an input interface for the collected flow signal of the electrolyte flowing out of the liquid flow battery stack, an input interface for the collected pressure signal of the electrolyte flowing into the liquid flow battery stack, and an input interface for the collected pressure signal of the electrolyte flowing out of the liquid flow battery stack.

[0039] Alternatively, if Figure 3As shown, in the above-mentioned liquid flow battery testing device 300, it also includes a switch input module 340, and the switch input module includes at least one of the following switch input interfaces: an input interface for collecting a liquid level status signal of a liquid storage tank for storing electrolyte, an input interface for collecting a valve status signal of a pipeline for electrolyte circulation, and an input interface for collecting a valve status signal of a pipeline for electrolyte cooling.

[0040] Alternatively, if Figure 3 As shown, in the above-mentioned liquid flow battery testing device 300, it also includes an analog output module 350, and the analog output module includes at least one of the following analog output interfaces: a control signal output interface for the valve opening of the pipeline for electrolyte circulation, and a control signal output interface for the valve opening of the pipeline for electrolyte cooling.

[0041] Alternatively, if Figure 3 As shown, in the above-mentioned liquid flow battery testing device 300, it also includes a switch output module 360, and the switch output module includes at least one of the following switch output interfaces: a start / stop control signal output interface of a liquid pump in a pipeline for electrolyte circulation, a start / stop control signal output interface of a pump in a pipeline for electrolyte cooling, and a sound / light alarm control signal output interface.

[0042] Alternatively, if Figure 3 As shown, in the above-mentioned flow battery testing device 300, a human-machine interface module 370 is also included, and the human-machine interface module includes at least one of the following: a display / touch screen, a keyboard, and a mouse.

[0043] Alternatively, if Figure 3 As shown, in the above-mentioned flow battery testing device 300, a communication module 380 is also included, and the communication module communicates with a host computer, a server and / or other terminals using at least one of the following communication protocols: Modbus, CAN, Ethernet / IP, USB.

[0044] As an example, in the above-mentioned liquid flow battery testing device 300, the control module 320 controls the bidirectional converter module 310 to charge and / or discharge the liquid flow battery with predetermined parameters based on preset working conditions.

[0045] As an example, in the above-mentioned liquid flow battery testing device 300, the control module 320 calculates at least one of the voltage efficiency, coulombic efficiency, energy efficiency, discharge energy, rated charging power, rated discharge power, and energy retention rate of the liquid flow battery based on the collected current and voltage data of the liquid flow battery energy storage system, and generates a test / test report according to the report template, wherein the test / test report includes at least one of the collected data, the numerical value of the calculation results and / or the graphical presentation.

[0046] Optionally, the utilization rate of the electrolyte and the utilization rate of the positive electrode active material may also be calculated based on relevant theoretical data of the battery stack.

[0047] Figure 4 The schematic diagram shows an assembly structure of a flow battery testing device using a compact frame according to an embodiment of the present disclosure. Figure 4 As shown, the liquid flow battery testing device may include a rack 410, which can accommodate and integrate various modules of the liquid flow battery testing device, and a ventilation and heat dissipation device can be configured in the rack shell so that various modules installed in the rack can operate in a suitable environment.

[0048] like Figure 4 As further shown, the flow battery testing device may also include a power distribution switch 420, a contactor 430 and a power supply 440, so as to supply power to each module in the flow battery testing device.

[0049] like Figure 4 As shown, the flow battery test device may further include a bidirectional converter module 470. As an example, the bidirectional converter module 470 is a multi-level module composed of a bidirectional converter and a DC-DC converter, which realizes bidirectional energy flow between batteries of different voltage levels and the industrial frequency AC power grid, and has functions such as charging, discharging, low-voltage charging, soft start, and voltage maintenance. As an example, the bidirectional converter module 470 can perform constant current, constant power, constant voltage, or other customized operating mode charging, discharging, operating condition simulation operation, etc. on the flow battery according to the set charging and discharging mode and charging and discharging parameters.

[0050] As an example, the bidirectional converter module 470 has the characteristics of high conversion efficiency and wide voltage input range, and also has protection functions such as over-voltage, under-voltage, overload, over-current, short circuit, and over-temperature.

[0051] As an example, by selecting bidirectional conversion modules with different parameters, higher voltage, larger current and higher power charging and discharging can be achieved.

[0052] As an example, the bidirectional converter module 470 can be connected to the control module and the host computer through Modbus protocol, CAN, Ethernet / IP, USB and other protocols to achieve functions such as control, monitoring and management of charging and discharging.

[0053] like Figure 4As shown, the flow battery testing device may further include a control module 500. The control module 500 may be a CPU module with an integrated connection function, which may be connected to a human-machine interface module such as an HMI touch screen through a wired or wireless network such as Ethernet or WiFi, thereby realizing functions such as operation and display. As an example, the control module 500 may be installed on a rack, or may be used as an independent control terminal; and may also be connected to a host computer through a wired or wireless network such as Ethernet or WiFi.

[0054] As an example, the control module 500 controls the entire test device and can complete sub-module control, parameter setting, action output, data collection, data processing, data storage, data calculation, report generation and other functions, and can export various stored data and reports.

[0055] The liquid flow battery testing device proposed according to the embodiment of the present disclosure can have a perfect battery protection function, which can be set according to the set values ​​of voltage, current, power, temperature, SOC (State of Charge), the change characteristics of voltage, current, power, temperature, SOC (State of Charge) (for example, integration, differentiation, such as first-order derivative, second-order derivative, and / or other calculated values, etc.) and / or their combined characteristics. Optionally, as an example, the control module 470 can calculate the set values, change characteristics, and combined characteristics of voltage, current, power, temperature, SOC (State of Charge) according to various functions set by the user, so as to provide perfect protection for the liquid flow battery during the test and experiment.

[0056] In addition, as an example, the control module 500 may also have a reporting function. For example, it may generate a test report containing data and charts such as rated discharge energy, maximum discharge energy, rated charging power, rated discharge power, rated energy efficiency, energy retention rate, voltage efficiency, coulomb efficiency, charging characteristic curve, and discharge characteristic curve according to the selected report template and standard.

[0057] like Figure 4 As shown, the flow battery test device may further include an analog quantity input module 510. As an example, the analog quantity input module 510 may provide an interface for voltage signals, current signals, current loop signals, thermocouple signals, thermal resistance signals, etc., and may be externally connected to sensors such as Hall, voltage, current, flow, temperature, pressure, liquid level, etc., and pre-process the collected signals related to various operating parameters of the battery stack, circulation system and / or temperature control system according to the set conversion formula, so as to be input into the control module for analysis, calculation and / or storage.

[0058] As an example, the analog input module 510 can be a module including 16-channel analog inputs, and the number of modules can be expanded as needed. It can receive inputs such as voltage signals and current loops. As an example, the input analog quantity may include 1 voltage, 1 current, 2 flow rates, 2 temperatures, and 2 pressure sensors, for example, 1 voltage and 1 current signal about the battery stack, 2 flow signals about the electrolyte flowing into and out of the battery stack, 2 temperature signals about the electrolyte flowing into and out of the battery stack, and 2 pressure signals about the electrolyte flowing into and out of the battery stack. As an example, the signal channel, signal name, etc. that need to be collected can be selected through the human-machine interface according to user needs.

[0059] like Figure 4 As shown, the flow battery test device may further include a switch input module 530. As an example, the switch input module 530 provides an interface for receiving signals such as contacts and levels. It can receive voltage feedback signals, control contact signals, liquid level contact signals, temperature contact signals, etc., so as to complete the input of the collected signals such as the start and stop status of the liquid pump of the circulation system and / or the temperature control system, the start and close status of the valve, the power supply and failure status, the liquid level exceeding the limit, the temperature exceeding the limit, etc. to the control module 500.

[0060] As an example, the switch input module 530 can be a DI module with 16 channels, and the number of modules can be expanded as needed, which can provide an interface for receiving switch contacts and status feedback signals. As an example, the status feedback signal can include 1 liquid circuit valve status, 1 water cooling valve status, and 1 liquid storage tank low liquid level alarm signal, which can be a passive dry contact signal. Optionally, according to user needs, the signal channel, signal name, etc. to be monitored can be selected through the human-machine interface.

[0061] like Figure 4 As shown, the flow battery test device may further include an analog output module 520. As an example, the analog output module 520 provides an output of a voltage signal, and may be externally connected to an electric control valve controller, a power amplifier, and other modules, and control the flow rate, temperature, and other quantities of a circulation system (e.g., an electrolyte circulation system) and a temperature control system (electrolyte temperature control system) according to the control curve / control value calculated by the control module 500.

[0062] As an example, the analog output module 520 can be a module including 8-channel analog output, and the number of modules can be expanded as needed; it can provide continuous analog voltage output; as an example, it can be externally connected to the control end of the electrolyte circulation pipeline valve (such as the liquid circuit valve) and the control end of the electrolyte temperature control system pipeline valve (such as the water cooling valve), and can realize the control of the opening of the liquid circuit valve and the water cooling valve under the control of the control module 500 based on the corresponding control algorithm.

[0063] like Figure 4 As shown, the flow battery test device may further include a switch output module 540. As an example, the switch output module 540 may output signals of control types such as contacts and levels, and may control components such as liquid pumps, power switches, status indicators, and sound and light alarms of the circulation system and temperature control system through external relays, signal lights, and the like.

[0064] As an example, the switch output module 540 can be an 8-channel DO module, and the number of modules can be expanded as needed. As an example, the switch output module 540 can provide a 24VDC voltage output, and through Figure 4 The relay 450 installed on the frame of the liquid flow battery testing device shown is connected to the contactor, display light, etc. to realize the functions of starting and stopping the liquid pump and alarm indication.

[0065] Optionally, in the above-mentioned flow battery testing device, a human-machine interface module is further included, and the human-machine interface module is connected to at least one of the following: a display / touch screen, a keyboard, and a mouse. Optionally, the keyboard, mouse, display / touch screen and other human-machine interface modules provide users with functions such as parameter setting, data display, and graphic display.

[0066] As an example, Figure 4 A touch screen 480 is further shown as an example of a human-machine interface module. For example, through the touch screen 480, the user can complete operations such as parameter setting of the flow battery, start and stop control of the liquid pump, data collection, data calculation, data storage, report generation, etc., and can display various test data, characteristic curves, test reports, etc.

[0067] As an example, Figure 4 As shown, the flow battery testing device may further include a communication module 490 .

[0068] As an example, the communication module 490 provides data communication functions such as field bus, Ethernet, WiFi, USB, etc., and can complete data exchange with inverters, temperature control devices, pressure transmitters, insulation monitoring devices, sealing detection devices, printers and other equipment and sensors with communication functions. It can also be networked with other network-supported devices or devices to complete complex multi-level collaborative testing tasks.

[0069] As an example, the communication module 490 can be a communication module that supports one or more protocols such as Modbus, CAN, Ethernet / IP, USB, WiFi, etc.; it can complete data exchange with bidirectional converter modules, insulation monitoring devices and other equipment with wired and / or wireless communication functions such as Modbus, CAN, Ethernet / IP, USB, WiFi, etc.

[0070] In addition, as an example, connection components such as a socket 460 and a connection terminal 550 may be installed on the rack 410 for connecting with other external devices.

[0071] Figure 5 The flow chart of the flow battery testing method proposed in the present disclosure is shown schematically. Figure 5 The flow battery testing method proposed in the present disclosure is described in detail.

[0072] like Figure 5 As shown, the liquid flow battery testing method according to the present disclosure may include: S510, setting monitoring parameters and protection parameters of the liquid flow battery to be tested; S520, configuring the test process and test parameters of the liquid flow battery; and S530, based on the configured test process and test parameters, performing charging and / or discharging tests on the liquid flow battery.

[0073] As an example, the above monitoring parameters and protection parameters include but are not limited to at least one of the following: voltage, current, power, temperature, and SOC of the flow battery.

[0074] By configuring the above monitoring parameters and protection parameters, the operation of the flow battery can be monitored and recorded in real time, abnormal situations during the test can be discovered and prevented, and the safety of the test can be improved.

[0075] As an example, the above monitoring parameters and protection parameters can be configured by calling a configuration file or manually setting. In addition, the above monitoring parameters and protection parameters may include calculated values ​​of monitoring parameters and / or protection parameters, such as the first-order derivative, second-order derivative, etc. of the monitoring value / protection value of the flow battery voltage, current, temperature, SOC and / or power; by setting the calculated values ​​of the relevant monitoring parameters and / or protection parameters, any abnormalities that may occur during the test can be discovered as early as possible based on the changing trends of the relevant monitoring parameters and / or protection parameters, so as to perform various alarms and protection actions, such as adjusting the valve opening on the electrolyte circulation system pipeline, adjusting the valve opening on the electrolyte temperature control system pipeline, etc.

[0076] As an example, based on the requirements of the test items, the test process and test parameters of the flow battery are configured through a test configuration file or manual settings, wherein the test process includes at least one of the following: static, single charge / discharge, multiple charge / discharge, cyclic charge / discharge, and the test parameters include charging voltage, discharge voltage, charging current, discharge current, charging power, discharge power, charging time, discharge time, charging termination voltage, discharge termination voltage, charging termination voltage characteristic value, and discharge termination voltage characteristic value. According to an embodiment of the present disclosure, the condition for charging termination may include that the charging voltage reaches the termination voltage or the calculated value of the charging voltage reaches the charging termination voltage characteristic value. As an example, the charging termination voltage characteristic value may include the first derivative of the charging voltage, the second derivative of the charging voltage, or other calculated values, such as the value obtained by integration, differentiation, derivation, or other calculations of the voltage. Similarly, according to an embodiment of the present disclosure, the condition for discharging termination may include that the discharge voltage reaches the termination voltage or the calculated value of the discharge voltage reaches the discharge termination voltage characteristic value. As an example, the discharge termination voltage characteristic value may include a first derivative of the discharge voltage, a second derivative of the discharge voltage, or other calculated values, such as a value obtained by integrating, differentiating, derivatizing, or otherwise calculating the voltage.

[0077] Figure 6 The detailed process of the flow battery testing method according to the embodiment of the present disclosure is schematically shown. Figure 6 As shown, the method includes, at S620, configuring monitoring parameters and protection parameters, and setting calculation parameters; as described above, the monitoring parameters and protection parameters may include various parameters of the flow battery, such as voltage, current, power, temperature, and SOC; in addition, the monitoring parameters and protection parameters may also include various parameters in the electrolyte circulation system and the electrolyte temperature control system, for example, the electrolyte flow rate, temperature, and pressure in the electrolyte circulation system, the opening of the valve in the circulation pipeline and other parameters; the flow rate, temperature, and pressure of the coolant in the electrolyte temperature control system, the opening of the valve in the cooling pipeline and other parameters, the liquid level of the electrolyte storage device, etc.; wherein, the calculation parameters may include the integration, differentiation, derivation, and other calculated values ​​of the above parameters.

[0078] like Figure 6 As shown, the monitoring parameters, protection parameters, and calculation parameters can be set by calling pre-stored monitoring parameter configuration files and protection parameter configuration files, or the monitoring parameters, protection parameters, and calculation parameters can be set and modified manually.

[0079] As an example, the method further includes, at S630, selecting a battery type, configuring battery parameters, and calculating parameter configuration; wherein, according to an embodiment, the flow battery test method disclosed herein can be applied to flow batteries such as all-vanadium flow batteries, zinc-bromine flow batteries, zinc-nickel flow batteries, zinc-iron flow batteries, iron-chromium flow batteries, and all-iron flow batteries; battery parameters can include, for example, rated charging voltage, rated charging current, maximum charging voltage, maximum charging current, rated discharge voltage, rated discharge current, maximum discharge voltage, and maximum discharge current. Similarly, the calculated parameters refer to the integral, differential, and other calculated values ​​of the above-mentioned battery parameters.

[0080] like Figure 6 As shown, the battery parameters can be set by calling a pre-stored battery parameter file, or the battery parameters can be set and modified manually.

[0081] As an example, the method further includes, at S640, setting a report template, which can be used to automatically generate a relevant test report at the end of the test. For example, the report template can be called to associate relevant test data, and a customized test report can be generated after the test is completed; some parameters or data can be calculated by integration, differentiation, derivation or other combinations to obtain calculated values, and these calculated values ​​can be associated in the report template.

[0082] As an example, the method further includes, at S650, performing test procedures and parameter configuration. For different test items, the test procedures and test parameters can be configured by manually setting or calling the test configuration file. Among them, test configuration files that meet the requirements of standards and specifications can be preset for different types of batteries for selection. As an example, the test process can include static, single charge / discharge under different parameters and conditions, multiple charge / discharge, cyclic charge / discharge and other test processes.

[0083] As an example, the method also includes, after all preparations are completed, in S660, starting the test, executing the charge and discharge test according to the test process and parameter configuration, and monitoring each monitoring point and each monitoring data of the test process according to the set monitoring parameters.

[0084] After each test process is completed in S660, the test is automatically ended in S670, and the test report can be automatically output according to the set report template in S680. As an example, the test report can include data, graphics, charts, etc.; the monitored data is recorded in real time in the storage medium, and after the test is completed, the stored data and graphics can be exported to a variety of file formats for subsequent use.

[0085] As an example, during the test, if an abnormal condition such as exceeding the system protection parameters is detected, an alarm will be issued, and the test can be interrupted and resumed at any time by operating the human-machine interface or setting the corresponding exception handling function.

[0086] Figure 7 FIG. 2 shows another process of a flow battery testing method according to an embodiment of the present disclosure. Figure 7 As shown, the method includes, after starting the test at S710, at S720, based on the test process, controlling the charge and discharge of the flow battery; for example, the flow battery can be charged and discharged once, multiple times, and cyclically charged and discharged through the bidirectional converter module. As an example, the bidirectional converter module is connected to the flow battery and the AC power grid to charge and / or discharge the flow battery, and it can be switched between a first operating mode and a second operating mode, wherein in the first operating mode, the flow battery is charged with electric energy from the AC power grid, and in the second operating mode, the flow battery is discharged to feed the electric energy from the flow battery back to the AC power grid.

[0087] As an example, the method also includes, during the test, S730, monitoring various parameters of the flow battery stack; S740, monitoring various parameters of the flow battery electrolyte circulation system; S750, monitoring various parameters of the flow battery electrolyte temperature control system; and when abnormal conditions such as exceeding system protection parameters are detected, as shown in S760, entering the system protection and abnormality handling process. For example, when it is detected that the electrolyte storage temperature exceeds the limit, the flow rate of the coolant of the electrolyte temperature control system will be increased.

[0088] During the test, the method further includes, at S770, detecting and recording various data of the flow battery during the test, and analyzing the recorded data at S780 to thereby determine the performance index of the flow battery. As an example, during the test, various data of the flow battery stack may be recorded, such as charging current, charging voltage, discharge current, discharge voltage, etc., thereby calculating the actual charging power, actual discharge power, and actual capacity, charging energy, discharge energy, and other performance indexes of the flow battery.

[0089] like Figure 7 As shown, after completing each test process at S785, the method may include, S790, automatically generating a test report.

[0090] Figure 8 FIG. 2 shows a flow battery testing method as an example of the present disclosure. Figure 8As shown, to ensure the accuracy of the test of the flow battery, before the flow battery stack is charged and discharged, as shown in S810, it can be left (stationary) in the test environment for a period of time, for example, 5 hours; then, in S820, the stack is discharged to the discharge termination voltage at the rated discharge power, and is stationary for a first period of time; as an example, the first period of time can be 30 minutes; in S830, the stack is charged to the charge termination voltage at the rated charging power, and is stationary for a second period of time; as an example, the second period of time can be the same as the first period of time, for example, 30 minutes. It should be noted that the time period can be changed depending on the actual situation of the stack and the test requirements. Figure 8 The order of S820 and S830 is not limited here.

[0091] In order to obtain the voltage efficiency, energy efficiency, coulombic efficiency, energy retention rate and other indicators of the flow battery, the voltage and current of the flow battery can be detected by cyclically charging and discharging the flow battery, and the corresponding indicators can be obtained by calculation. Figure 8 As further shown, at S840, the flow battery stack is discharged at a constant power to a discharge termination voltage; at S850, the flow battery stack is charged at a constant power to a charge termination voltage; it should be noted that the voltage may be changed depending on the actual situation of the stack and the test requirements. Figure 8 The order of S840 and S850 is not limited here.

[0092] At S860, after determining that the battery stack has been subjected to constant power charge and discharge cycles N times, various performance indicators of the battery can be calculated at S870. For example, the average charging voltage V of N constant power charge and discharge cycles can be calculated. c , average discharge voltage V d , thus obtaining the battery voltage efficiency η v :

[0093]

[0094] Calculate the average charging energy E of N constant power charge and discharge cycles c , average discharge energy E d , thereby obtaining the energy efficiency η of the battery E :

[0095]

[0096] Calculate the average discharge ampere-hour capacity A of N constant power charge and discharge cycles d , average charging ampere-hour capacity A c , thus obtaining the coulombic efficiency η of the battery c :

[0097]

[0098] As an example, N may be equal to 3. Of course, N may also take other values ​​according to test requirements.

[0099] As an example, after S840 and S850 are cycled K times, the net discharge energy E of K constant power charge and discharge cycles can be calculated. d’ , Rated discharge energy E r , thereby obtaining the battery energy retention rate R:

[0100]

[0101] As an example, K = 99. Of course, K may also take other values ​​according to test requirements.

[0102] Fig. 9 FIG. 2 shows a display screen of a human-machine interface of a flow battery testing device according to an embodiment of the present disclosure. Fig. 9 As shown, through the human-machine interface, various parameters and states of the flow battery stack, electrolyte circulation system, and electrolyte temperature control system can be monitored, and parameters can be set accordingly and reports can be generated.

[0103] Figures 10A-10F The relevant data curves obtained during the test of the flow battery according to the embodiment of the present disclosure are respectively shown; wherein, Fig. 10A A curve showing the constant current charge and discharge voltage of a flow battery; Fig. 10B shows the curve of constant current charge and discharge of flow battery; Fig. 10C The flow rate curve in the electrolyte circulation pipeline (the flow rate of the two liquid inlet pipes at the inlet) is shown; Fig. 10D The temperature curve (inlet and outlet temperature) in the electrolyte circulation pipeline is shown; Fig. 10E The pressure curve in the electrolyte circulation pipeline is shown (the inlet or outlet pressure can be selected according to the test requirements); Fig.10F The voltage and current curves of the flow battery during three constant power cycle charge and discharge are shown.

[0104] As an example, based on Fig.10F The voltage and current test waveforms of the flow battery in the three constant power charge and discharge cycles shown in the figure can be used to calculate the battery voltage efficiency η v The battery energy efficiency η is 87.8%. E It is 85.2%.

[0105] According to the liquid flow battery testing device and method of the embodiments of the present disclosure, various modules for testing, debugging, controlling and monitoring various functions of the battery stack and the supporting circulation and temperature control systems in various stages of research and development and production are integrated, which is easy to implement parameter adaptation, and is convenient for collecting, storing, analyzing and displaying various parameter data. It can realize functions such as status monitoring and operation protection of the battery stack and its supporting circulation and temperature control systems, thereby improving work efficiency and reducing testing costs.

[0106] Thus, several aspects of the present disclosure are presented above with reference to various devices and methods. These devices and methods are illustrated in the accompanying drawings by various modules, components, circuits, processes, algorithms, etc. (collectively referred to as "elements"). These elements can be implemented using electronic hardware, computer software, or any combination thereof. Whether these elements are implemented as hardware or software depends on the specific application and the design constraints on the overall system.

[0107] In the present disclosure, unless otherwise clearly specified and limited, the terms "installed", "set", "connected", "connected", "fixed", "coupled" and the like should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection, an electrical connection, or a communication connection with each other; it can be a direct connection, or an indirect connection through an intermediate medium, it can be the internal connection of two elements or the interaction relationship between two elements, unless otherwise clearly defined. For ordinary technicians in this field, the specific meanings of the above terms in the present disclosure can be understood according to specific circumstances.

[0108] Obviously, the embodiments described above are only some embodiments of the present application, rather than all embodiments. The preferred embodiments of the present application are given in the accompanying drawings, but they do not limit the patent scope of the present application. The present application can be implemented in many different forms. On the contrary, the purpose of providing these embodiments is to make the understanding of the disclosure of the present application more thorough and comprehensive. Although the present application is described in detail with reference to the aforementioned embodiments, for those skilled in the art, it is still possible to modify the technical solutions recorded in the aforementioned specific implementation methods, or to perform equivalent replacement of some of the technical features therein. All equivalent structures made using the contents of the present application specification and the accompanying drawings, directly or indirectly used in other related technical fields, are within the scope of patent protection of the present application.

Claims

1. A flow battery testing method, comprising: Setting monitoring parameters and protection parameters of the flow battery to be tested, wherein the monitoring parameters and protection parameters include at least one of the following: voltage, current, power, temperature, SOC; Based on the requirements of the test items, the test process and test parameters of the flow battery are configured through the test configuration file or manual settings, wherein the test process includes at least one of the following: static, single charge / discharge, multiple charge / discharge, and cyclic charge / discharge, and the test parameters include at least one of the following: charging voltage, discharging voltage, charging current, discharging current, charging power, discharging power, charging time, discharging time, charging termination voltage, discharging termination voltage, charging termination voltage characteristic value, and discharging termination voltage characteristic value; as well as Based on the configured test procedure and test parameters, the flow battery is charged and / or discharged.

2. The method according to claim 1, further comprising: Switchable between a first operation mode and a second operation mode, wherein in the first operation mode, electric energy from the AC grid is provided to the flow battery to charge the flow battery, and in the second operation mode, electric energy from the flow battery is fed back to the AC grid to discharge the flow battery; At least one of the first operation mode and the second operation mode includes at least one of a constant current mode, a constant voltage mode or a constant power mode.

3. The method according to claim 1 or 2, further comprising: Collect at least one operating parameter of the flow battery stack, electrolyte, circulation system, and temperature control system during the test for real-time display; wherein the operating parameter includes at least one of the following: The current and voltage of the liquid flow battery stack, the temperature of the electrolyte flowing into the liquid flow battery stack, the temperature of the electrolyte flowing out of the liquid flow battery stack, the flow rate of the electrolyte flowing into the liquid flow battery stack, the flow rate of the electrolyte flowing out of the liquid flow battery stack, the pressure of the electrolyte flowing into the liquid flow battery stack, the pressure of the electrolyte flowing out of the liquid flow battery stack, the liquid level status of the storage tank for storing the electrolyte, the valve status of the pipeline used for electrolyte circulation, and the valve status of the pipeline used for electrolyte cooling.

4. The method according to claim 3, further comprising: Based on the collected operating parameters of at least one of the flow battery stack, electrolyte, circulation system, and temperature control system, at least one of the following control signals can be generated and output: a control signal for the valve opening of the pipeline for electrolyte circulation, a control signal for the valve opening of the pipeline for electrolyte cooling, a control signal for starting and stopping the liquid pump of the pipeline for electrolyte circulation, a control signal for starting and stopping the pump of the pipeline for electrolyte cooling, and an audio / visual alarm control signal.

5. The method according to claim 3, further comprising: Generate a test report based on the collected operating parameters of at least one of the flow battery stack, electrolyte, circulation system, and temperature control system; The test report includes at least one of the following data or charts: rated discharge energy, maximum discharge energy, rated charging power, rated discharge power, rated energy efficiency, energy retention rate, voltage efficiency, and coulombic efficiency of the flow battery.

6. The method according to claim 3, further comprising: Based on the current signal and voltage signal of the flow battery collected during multiple cycles of charge / discharge in constant power mode, the rated discharge energy, maximum discharge energy, rated charging power, rated discharge power, rated energy efficiency, energy retention rate, voltage efficiency, and coulombic efficiency of the flow battery are calculated.

7. A flow battery testing device, comprising: A control module, used to implement the method described in any one of claims 1 to 6; as well as The bidirectional conversion module is connected to the liquid flow battery and the AC power grid to charge and / or discharge the liquid flow battery.

8. The flow battery testing device according to claim 7, further comprising: An analog quantity input module, the analog quantity input module comprising at least one of the following analog quantity input interfaces: an input interface for a collected current signal of a liquid flow battery, an input interface for a collected voltage signal of a liquid flow battery, an input interface for a collected temperature signal of an electrolyte flowing into a liquid flow battery stack, an input interface for a collected temperature signal of an electrolyte flowing out of a liquid flow battery stack, an input interface for a collected flow signal of an electrolyte flowing into a liquid flow battery stack, an input interface for a collected flow signal of an electrolyte flowing out of a liquid flow battery stack, an input interface for a collected pressure signal of an electrolyte flowing into a liquid flow battery stack, and an input interface for a collected pressure signal of an electrolyte flowing out of a liquid flow battery stack; and / or The analog output module includes at least one of the following analog output interfaces: a control signal output interface for the valve opening of a pipeline for electrolyte circulation, and a control signal output interface for the valve opening of a pipeline for electrolyte cooling.

9. The flow battery testing device according to claim 7 or 8, further comprising: A switch quantity input module, the switch quantity input module comprising at least one of the following switch quantity input interfaces: an input interface for collecting a liquid level status signal of a liquid storage tank for storing electrolyte, an input interface for collecting a valve status signal of a pipeline for electrolyte circulation, an input interface for collecting a valve status signal of a pipeline for electrolyte cooling; and / or A switch quantity output module, the switch quantity output module includes at least one of the following switch quantity output interfaces: a start / stop control signal output interface of a liquid pump in a pipeline for electrolyte circulation, a start / stop control signal output interface of a pump in a pipeline for electrolyte cooling, and an audio / visual alarm control signal output interface.

10. The flow battery testing device according to claim 7 or 8, further comprising a human-machine interface module, wherein: The human-machine interface module includes at least one of the following: a display / touch screen, a keyboard, and a mouse.

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