Flow battery and electrode frame and electrolyte distribution method thereof

Abstract

The invention relates to a flow battery and an electrode frame and an electrolyte distribution method thereof, the electrode frame is applied to the flow battery comprising a plurality of single batteries connected in series, each single battery at least comprises a positive electrode, a negative electrode and a diaphragm, and the positive electrode and the negative electrode are respectively embedded in the corresponding electrode frame; the electrode frame specifically comprises a frame body, wherein the frame body comprises a liquid inlet flow channel and a liquid outlet flow channel which are used for circulating electrolyte; and the flow monitoring module is arranged in the frame body and is used for monitoring the electrolyte flow of the liquid inlet flow channel and regulating and controlling the electrolyte flow to be consistent with target flow, and the target flow is determined according to the charging and discharging working conditions of the flow battery. The electrolyte flow adjusting device is additionally arranged on the single battery, so that the opening degree of the internal liquid inlet flow channel is dynamically adjusted, the flow of the electrolyte entering each electrode frame is controlled and optimized, the uniform distribution of the electrolyte of each single battery in the whole flow battery is ensured, and the flow rate of the battery is improved. Therefore, the charge-discharge efficiency and the conversion performance of the whole flow battery are comprehensively improved.

Description

Technical Field

[0001] The present application relates to the technical field of energy storage, and particularly to a flow battery, an electrode frame thereof, and an electrolyte distribution method. Background Art

[0002] With the development of energy technologies, as a new type of battery energy storage technology, flow batteries have the advantages of high safety, long cycle life, easy adjustment of energy storage capacity, large freedom in site selection, good charge and discharge performance, environmental protection and low carbon, and play an increasingly important role in the energy market.

[0003] A flow battery is a high-performance battery technology that separates the positive and negative electrolytes and circulates them separately. It can achieve the mutual conversion of electrical energy and chemical energy through the reversible oxidation-reduction reaction of the active substances in the positive and negative electrolyte solutions. During charging, the oxidation reaction occurs at the positive electrode to increase the valence state of the active substance, and the reduction reaction occurs at the negative electrode to lower the valence state of the active substance; the opposite occurs during discharging. In the application of flow batteries, the uniform distribution and effective flow of the electrolyte are crucial for improving battery performance and extending battery life. How to achieve precise distribution of the electrolyte has also become a technical problem to be solved urgently. Summary of the Invention

[0004] Based on this, in view of the above technical problem of how to achieve precise distribution of the electrolyte, it is necessary to provide a flow battery, an electrode frame thereof, and an electrolyte distribution method.

[0005] An electrode frame of a flow battery is applied to a flow battery including a plurality of single-cell batteries connected in series. Each of the single-cell batteries includes at least a positive electrode, a negative electrode, and a separator. The positive electrode and the negative electrode are respectively embedded in corresponding electrode frames.

[0006] The electrode frame includes:

[0007] A frame body, which includes an inlet flow channel and an outlet flow channel for circulating the electrolyte.

[0008] A flow rate monitoring module is arranged on the frame body for monitoring the flow rate of the electrolyte in the inlet flow channel and regulating the flow rate of the electrolyte to be consistent with a target flow rate, where the target flow rate is determined according to the charge and discharge conditions of the flow battery.

[0009] In one embodiment, the flow rate monitoring module includes a flow rate acquisition unit, a data transmission unit, and a flow rate adjustment device. The flow rate acquisition unit is connected to the data transmission unit. The data transmission unit is connected to the control module of the flow battery, and the data transmission unit is also connected to the flow rate adjustment device.

[0010] The flow rate acquisition unit is configured to acquire the electrolyte flow rate of the liquid inlet channel and send the electrolyte flow rate to the control module through the data transmission unit;

[0011] The data transmission unit is further configured to receive the opening adjustment instruction sent by the control module and transmit the opening adjustment instruction to the flow rate adjustment device;

[0012] The flow rate adjustment device is configured to change the opening according to the opening adjustment instruction so that the electrolyte flow rate is consistent with the target flow rate.

[0013] In one embodiment, the number of the liquid inlet channels is two or more;

[0014] The flow rate acquisition unit is configured to acquire the electrolyte flow rates of the respective liquid inlet channels, aggregate the total electrolyte flow rate, and send it to the control module through the data transmission unit;

[0015] The flow rate adjustment device is configured to change the opening according to the opening adjustment instruction so that the total electrolyte flow rate is consistent with the target flow rate.

[0016] In one embodiment, the electrode frame further includes:

[0017] A pressure monitoring unit configured to acquire the electrolyte pressure of the liquid inlet channel and send the electrolyte pressure to the control module through the data transmission unit;

[0018] The data transmission unit is further configured to receive the shut-off instruction sent by the control module and transmit the shut-off instruction to the flow rate adjustment device;

[0019] The flow rate adjustment device is further configured to shut off the liquid inlet channel according to the shut-off instruction.

[0020] In one embodiment, the flow rate monitoring module is disposed on the side surface of the frame body.

[0021] In one embodiment, an electrolyte distribution area communicating with the liquid inlet channel is further included in the frame body, and the electrolyte distribution area is provided with a gradually widening flow guiding structure.

[0022] In one embodiment, a flow battery is provided, and the flow battery includes a flow battery body and a control module, and the control module is connected to the flow battery body;

[0023] The flow battery body includes a plurality of single cells connected in series, and each single cell includes at least a positive electrode, a negative electrode, and a separator, and the positive electrode and the negative electrode are respectively embedded in the electrode frame as described above;

[0024] The control module is used to determine a target flow rate according to the charge-discharge condition of the flow battery body, obtain the electrolyte flow rate of each inlet flow channel monitored by the electrode frame, and output an opening adjustment command according to the deviation analysis of the electrolyte flow rate and the target flow rate.

[0025] In one embodiment, an electrolyte distribution method is provided, and the method includes:

[0026] Obtain the charge-discharge condition of the flow battery body and the electrolyte flow rate of each inlet flow channel;

[0027] Determine a target flow rate according to the charge-discharge condition of the flow battery body;

[0028] Perform deviation analysis based on the electrolyte flow rate and the target flow rate, and output an opening adjustment command.

[0029] In one embodiment, the determining the target flow rate according to the charge-discharge condition of the flow battery body includes:

[0030] Obtain the battery voltage of the flow battery body;

[0031] Determine the target charge-discharge stage in which the flow battery body is located based on the battery voltage;

[0032] Determine the target flow rate corresponding to the target charge-discharge stage.

[0033] In one embodiment, the method further includes:

[0034] Obtain the electrolyte pressure of each inlet flow channel;

[0035] Output a shutdown command when the electrolyte pressure exceeds the pressure protection threshold.

[0036] The above-mentioned flow battery, its electrode frame, and electrolyte distribution method. The electrode frame is applied to a flow battery including a plurality of single-cell batteries connected in series. Each single-cell battery includes at least a positive electrode, a negative electrode, and a separator. The positive electrode and the negative electrode are respectively embedded in the corresponding electrode frames. The electrode frame specifically includes: a frame body, the frame body includes an inlet flow channel and an outlet flow channel for circulating electrolyte; a flow rate monitoring module, arranged on the frame body, for monitoring the electrolyte flow rate of the inlet flow channel and regulating the electrolyte flow rate to be consistent with the target flow rate, wherein the target flow rate is determined according to the charge-discharge condition of the flow battery. By adding an electrolyte flow rate adjustment device to the single-cell battery, the dynamic adjustment of the opening degree of the internal inlet flow channel is realized, so as to control and optimize the electrolyte flow rate entering each electrode frame, ensure the uniform distribution of the electrolyte in each single-cell battery of the entire flow battery, and thus comprehensively improve the charge-discharge efficiency and conversion performance of the entire flow battery. Description of the Drawings

[0037] To more clearly illustrate the technical solutions in the embodiments of the present application or related technologies, the following will briefly introduce the drawings required for the description of the embodiments of the present application or related technologies. Obviously, the drawings in the following description are only some embodiments of the present application. For those of ordinary skill in the art, without creative efforts, other related drawings can also be obtained based on these drawings.

[0038] Figure 1 It is a partial structural schematic diagram of an electrode frame in an embodiment;

[0039] Figure 2 It is a schematic block diagram of a flow battery system in an embodiment;

[0040] Figure 3 It is a structural schematic diagram of a flow monitoring module in an embodiment;

[0041] Figure 4 It is a structural schematic diagram of multiple liquid inlet channels in an embodiment;

[0042] Figure 5 It is a side view structural schematic diagram of multiple liquid inlet channels in an embodiment;

[0043] Figure 6 It is a structural schematic diagram between a flow monitoring module and a frame body in an embodiment;

[0044] Figure 7 It is a schematic flowchart of an electrolyte distribution method in an embodiment;

[0045] Figure 8 It is a schematic flowchart of an electrolyte distribution method in another embodiment;

[0046] Figure 9 It is a schematic flowchart of an electrolyte distribution method in yet another embodiment. Detailed implementation manners

[0047] In order to make the purpose, technical solutions and advantages of the present application clearer, the following further details the present application in combination with the drawings and embodiments. Embodiments of the present application are given in the drawings, but the present application can be implemented in many different forms and is not limited to the embodiments described herein. On the contrary, the purpose of providing these embodiments is to make the disclosure of the present application more thorough and comprehensive. It should be understood that the specific embodiments described herein are only used to explain the present application and are not used to limit the present application.

[0048] It will be understood that the terms "first", "second", etc. used in this application may be used herein to describe various elements, but these elements are not limited by these terms. These terms are only used to distinguish a first element from another element. For example, without departing from the scope of this application, a first resistor may be referred to as a second resistor, and similarly, a second resistor may be referred to as a first resistor. Both the first resistor and the second resistor are resistors, but they are not the same resistor.

[0049] It will be understood that for "connection" in the following embodiments, if there is transmission of electrical signals or data between the connected circuits, modules, units, etc., it should be understood as "electrical connection", "communication connection", etc.

[0050] It will be understood that "at least one" means one or more, and "a plurality" means two or more. "At least a part of an element" means part or all of the element.

[0051] As used herein, the singular forms "a", "an" and "the" may also include the plural forms unless the context clearly dictates otherwise. It should also be understood that the terms "comprise / include" or "have" etc. specify the presence of the stated features, wholes, steps, operations, components, parts or combinations thereof, but do not preclude the presence or addition of one or more other features, wholes, steps, operations, components, parts or combinations thereof. At the same time, the term "and / or" used in this specification includes any and all combinations of the related listed items.

[0052] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the technical field to which this application belongs. The terms used in the specification of this application are only for the purpose of describing specific embodiments and are not intended to limit this application.

[0053] Exemplarily, this application provides a flow battery, including a flow battery body. Wherein, the flow battery body includes a plurality of single cells connected in series, and each single cell includes at least a positive electrode, a negative electrode and a separator, and the positive electrode and the negative electrode are respectively embedded in corresponding electrode frames.

[0054] Specifically, the liquid flow battery body is the core part of the liquid flow battery and can also be called a stack, which includes multiple single cells connected in series. Each single cell includes at least a positive electrode, a negative electrode, and a separator. Among them, the positive electrode and the negative electrode are electrodes connected to voltages of different polarities and are the places where electrochemical reactions occur in the liquid flow battery. Since the electrodes need to have good electrical conductivity, chemical stability, and catalytic activity, graphite felt is often used as the electrode material in some embodiments. The separator is used to prevent the mixing of the positive and negative electrode electrolytes and at the same time allow ions to pass through. The selection of its material has an important impact on the internal resistance and safety performance of the liquid flow battery. Commonly used separator materials include ion exchange membranes, microporous membranes, etc.

[0055] Furthermore, both the positive electrode and the negative electrode can be embedded in their corresponding electrode frames, and the electrode frames can play the roles of organizing the flow, distribution, and supporting the electrodes of the electrolyte. It can be understood that the electrolyte is the medium for storing energy in the liquid flow battery and contains active substances that can support redox reactions. Exemplarily, the liquid flow battery may further include components such as a liquid storage tank and a pump element. The liquid storage tank is used to store the electrolyte, and the pump element is used to transport the electrolyte from the liquid storage tank to the electrode frame of the liquid flow battery body for reaction and then send it back to the liquid storage tank after the reaction. When the liquid flow battery starts to work, the electrolyte can circulate in the liquid flow battery under the action of the pump element. Among them, the electrolyte used in the liquid flow battery provided by the embodiments of the present application is not fixed, and different types of liquid flow batteries use different active substances. For example, all-vanadium liquid flow batteries use different valence states of vanadium ions as active substances, while zinc-based liquid flow batteries use zinc ions. It can also be types such as iron-chromium liquid flow batteries, all-iron liquid flow batteries, polysulfide sodium / bromine liquid flow batteries, etc.

[0056] In an exemplary embodiment, an electrode frame of a liquid flow battery is provided, as Figure 1 shown, the electrode frame includes: a frame body 100, the frame body 100 includes an inlet flow channel 110 for circulating the electrolyte and an outlet flow channel (not shown in the figure); a flow monitoring module 120, disposed on the frame body 100, for monitoring the electrolyte flow rate of the inlet flow channel 110 and regulating the electrolyte flow rate to be consistent with the target flow rate, where the target flow rate is determined according to the charge and discharge conditions of the liquid flow battery.

[0057] It can be understood that the electrode frame with the flow monitoring module 120 provided in this embodiment can be used to fit the positive electrode and / or negative electrode in a single cell to form a flow battery with controllable electrolyte flow. Specifically, the application of the electrode frame provided in this embodiment within the overall flow battery is not limited. It can be that the positive and negative electrodes of all single cells are embedded in the electrode frame provided in this embodiment, or the positive and negative electrodes of some single cells are embedded in the electrode frame provided in this embodiment, and the other single cells are fitted with ordinary electrode frames. It can also be that the positive / negative electrodes of all single cells are embedded in the electrode frame provided in this embodiment, while the negative / positive electrodes are fitted with ordinary electrode frames. It can also be that some of the positive and negative electrodes of all single cells are selected according to technical requirements and embedded in the electrode frame provided in this embodiment, and the others are fitted with ordinary electrode frames.

[0058] Among them, the frame body 100 can be understood as the support base structure of the electrode frame, which is made of materials with excellent chemical stability and mechanical strength. For example, it can be made of polyvinylidene fluoride or reinforced composite materials. The shape and size of the frame body 100 are not fixed and can be designed according to actual technical requirements.

[0059] The inlet flow channel 110 is the electrolyte flow channel for the electrolyte to flow into the frame body 100 from the outside. The inlet of the inlet flow channel 110 can be connected to the pump element and the liquid storage tank through a common inlet flow channel, and the outlet of the inlet flow channel 110 is connected to the electrode placement area. The outlet flow channel is the electrolyte flow channel for the electrolyte to flow out of the frame body 100 from the electrode placement area. The inlet of the outlet flow channel is connected to the electrode placement area, and the outlet of the outlet flow channel is connected to the liquid storage tank through a common outlet flow channel. It can be understood that the electrolyte flows into the electrode placement area within the frame body 100 through the inlet flow channel 110 and flows back to the liquid storage tank through the outlet flow channel after the reaction.

[0060] Specifically, the flow monitoring module 120 is a module for controlling the opening degree of the inlet flow channel 110 to achieve the adjustment and distribution of the electrolyte flow required for this single cell. The flow monitoring module 120 is arranged on the frame body 100. It can first monitor the electrolyte flow in the inlet flow channel 110, and when it is determined that there is a deviation between the electrolyte flow and the target flow, adjust the opening degree of the inlet flow channel 110 to control the electrolyte flow to be consistent with the target flow. Among them, the process of adjusting the opening degree of the inlet flow channel 110 according to the flow deviation between the electrolyte flow and the target flow can be realized by the controller and the flow regulating device set in the flow monitoring module 120 itself, or the flow monitoring module 120 communicates with an external controller, and the external controller performs PID automatic adjustment on the opening degree of the inlet flow channel 110.

[0061] Among them, the target flow rate is the target value to which the electrolyte flow rate in the liquid inlet channel 110 needs to be adjusted, and it can be determined according to the charge and discharge conditions of the flow battery. As the charge and discharge of the flow battery proceed, the reaction of the electrolyte between the positive and negative electrodes gradually changes, which also leads to changes in the demand for the electrolyte. For example, as the charging process of the flow battery proceeds, the electrolyte fully reacts, which also causes the demand for the electrolyte to increase. Furthermore, it is necessary to adjust the opening degree of the liquid inlet channel 110 so that a larger electrolyte flow rate can be obtained for a single cell, thereby achieving the purpose of improving the charge and discharge efficiency of the flow battery. Exemplarily, the process of determining the target flow rate according to the charge and discharge conditions of the flow battery may be to first obtain the battery voltage of the flow battery body, then determine the target charge and discharge stage in which the flow battery body is located based on the battery voltage, and finally determine the target flow rate corresponding to the target charge and discharge stage.

[0062] Meanwhile, for the liquid inlet channels 110 of different electrode frames, as the usage time increases, the electrolyte flow rate values corresponding to the same opening degree may change. Furthermore, it is necessary to monitor the electrolyte flow rate in the liquid inlet channel 110 in real time, and when it is determined that there is a deviation between the electrolyte flow rate and the target flow rate, adjust the opening degree of the liquid inlet channel 110 to meet the target flow rate, which can also make the electrolyte of each single cell in the entire flow battery evenly distributed.

[0063] The electrode frame of the above-mentioned flow battery includes a frame body, and the frame body includes a liquid inlet channel and a liquid outlet channel for circulating the electrolyte; a flow rate monitoring module is arranged on the frame body for monitoring the electrolyte flow rate in the liquid inlet channel and regulating the electrolyte flow rate to be consistent with the target flow rate, wherein the target flow rate is determined according to the charge and discharge conditions of the flow battery. By adding an electrolyte flow rate regulating device to a single cell, the dynamic adjustment of the opening degree of the internal liquid inlet channel is realized, thereby controlling and optimizing the electrolyte flow rate entering each electrode frame, ensuring the uniform distribution of the electrolyte of each single cell in the entire flow battery, and thus comprehensively improving the charge and discharge efficiency and conversion performance of the entire flow battery.

[0064] In the following embodiments, the example in which the flow rate monitoring module 120 communicates with an external controller to control the opening degree of the liquid inlet channel 110 will be used for illustration.

[0065] Correspondingly, in an exemplary embodiment, such as Figure 2As shown in the figure, a flow battery is provided. The flow battery includes a flow battery body 210 and a control module 220. The control module 220 is connected to the flow battery body 210. The flow battery body 210 includes a plurality of single cells connected in series. Each single cell includes at least a positive electrode, a negative electrode, and a separator. The positive electrode and the negative electrode are respectively embedded in the electrode frames. The control module 220 is used to determine a target flow rate according to the charge and discharge conditions of the flow battery body 210, obtain the electrolyte flow rates of the respective inlet channels monitored by the electrode frames, and output an opening adjustment command based on the deviation analysis of the electrolyte flow rates and the target flow rate.

[0066] Among them, the control module 220 is the external controller relative to the relative flow rate monitoring module 120 and is also the control center of the flow battery, used to control the operating state during the use of the flow battery. In addition to the opening control of the above-mentioned respective inlet channels, the functions of the control module 220 may also include the monitoring of parameters such as voltage, current, and temperature, as well as the equalization, fault diagnosis, and protection of the flow battery, etc., to maintain it in the best working state and ensure the safe and efficient operation of the flow battery.

[0067] Specifically, for the flow rate monitoring module 120 on the electrode frame, after the flow rate monitoring module 120 monitors the electrolyte flow rate of the inlet channel 110, the control module 220 can determine the target flow rate according to the charge and discharge conditions of the flow battery, and then output an opening adjustment command to adjust the opening of the inlet channel 110 based on the deviation analysis of the electrolyte flow rates of the respective inlet channels 110 and the target flow rate.

[0068] Among them, when the control module 220 obtains the target flow rate, it can first obtain the battery voltage of the flow battery body 210, then determine the target charge and discharge stage in which the flow battery body 210 is located based on the battery voltage, and finally determine the target flow rate corresponding to the target charge and discharge stage. Specifically, according to the charge and discharge characteristics of the flow battery, the battery voltage can be divided into multiple charge and discharge stages from low to high in advance. Among them, the charge stage and the discharge stage corresponding to the same battery voltage can be the same or different, which is determined according to the parameters of the actual flow battery. Furthermore, during the actual adjustment process, after obtaining the actual battery voltage of the flow battery body 210, the target charge and discharge stage in which the flow battery body 210 is located can be determined based on the battery voltage, and then the flow target value corresponding to the target charge and discharge stage is determined as the target flow rate.

[0069] It can be understood that during the early product testing phase, the division of the charge and discharge phases and their corresponding flow target values can be determined in advance based on pre-test data. Taking the charging phase as an example, according to the pre-test, the battery voltage can be divided into three charging phases from low to high: a-b, b-c, and c-d. And according to the pre-test, the flow target value corresponding to the a-b charging phase is set to value A, the flow target value corresponding to the b-c charging phase is set to value B, and the flow target value corresponding to the c-d charging phase is set to value C. Furthermore, during the actual adjustment process, if the actual battery voltage is in the a-b charging phase, the target flow can be determined as value A, and so on.

[0070] For the embodiments of the present application, to ensure that the electrolyte of each single battery reacts fully, the above-determined target flows are all the target flows required for the full reaction of the single battery, and are used to control the opening degree of the liquid inlet flow channel on the electrode frame of the single battery. In addition, to achieve the dynamic balance of the electrolyte flow in all single batteries in the flow battery, the target flows determined for the same target charge and discharge phase of all single batteries in the present application embodiment are the same. Of course, in some embodiments, for the operation requirements of the flow battery, the target flows determined for the same target charge and discharge phase of multiple single batteries can also be set to different flow values.

[0071] Furthermore, the way for the control module 220 to output the opening degree adjustment instruction is not unique. It can be to calculate the flow deviation value between the electrolyte flow and the target flow, and then output the opening degree adjustment instruction according to the corresponding relationship between the flow deviation value and the opening degree of the liquid inlet flow channel, so as to use fewer adjustment times to make the electrolyte flow reach the same as the target flow. It can also be to determine the opening degree adjustment direction of the liquid inlet flow channel based on the deviation analysis of the electrolyte flow and the target flow, and then output a directional instruction for adjustment with a preset fixed step length until the electrolyte flow reaches the same as the target flow. For example, when it is analyzed that the electrolyte flow is greater than the target flow, an instruction to reduce the opening degree of the liquid inlet flow channel with a preset fixed step length is output, and when it is analyzed that the electrolyte flow is less than the target flow, an instruction to increase the opening degree of the liquid inlet flow channel with a preset fixed step length is output. Of course, when it is determined based on the deviation analysis of the electrolyte flow and the target flow that the electrolyte flow has reached the same as the target flow, it can be not to output the opening degree adjustment instruction, or to output an opening degree adjustment instruction to keep the opening degree unchanged.

[0072] In this embodiment, by determining the target flow based on the charge and discharge conditions of the flow battery body, the opening degree control of the liquid inlet flow channel is realized, providing high flexibility for the electrolyte flow control of the flow battery under different working states.

[0073] In an exemplary embodiment, such as Figure 3As shown in the figure, the flow monitoring module 120 includes a flow collection unit 121, a data transmission unit 122, and a flow regulating device 123. The flow collection unit 121 is connected to the data transmission unit 122, the data transmission unit 122 is connected to the control module of the flow battery, and the data transmission unit 122 is also connected to the flow regulating device 123. The flow collection unit 121 is configured to collect the electrolyte flow rate of the inlet flow channel 110 and send the electrolyte flow rate to the control module through the data transmission unit 122. The data transmission unit 123 is further configured to receive the opening degree adjustment instruction sent by the control module and transmit the opening degree adjustment instruction to the flow regulating device 123. The flow regulating device 123 is configured to change the opening degree according to the opening degree adjustment instruction so that the electrolyte flow rate is consistent with the target flow rate.

[0074] Specifically, the flow collection unit 121 is a unit for collecting the electrolyte flow rate of the inlet flow channel, which can be realized by setting a flow meter on the inlet flow channel. The type of the flow meter adopted in the flow collection unit 121 is not limited, and different flow collection principles can be selected according to the actual electrolyte characteristics. For example, an electromagnetic flow meter can be used, or an ultrasonic flow meter can be used, or a positive displacement flow meter and a differential pressure flow meter can be used, etc.

[0075] Further, the data transmission unit 122 can transmit the electrolyte flow rate of the inlet flow channel 110 collected by the flow collection unit 121 to the control module of the flow battery, so that the control module performs deviation analysis based on the electrolyte flow rate and the target flow rate and outputs an opening degree adjustment instruction. The data transmission unit 122 can also receive the opening degree adjustment instruction output by the control module and send the opening degree adjustment instruction to the flow regulating device. In the embodiments of the present application, the data transmission unit 122 can be implemented based on wireless transmission technology. For example, wireless modules such as Bluetooth, WiFi, Zigbee, and LoRa can be used.

[0076] Furthermore, the flow rate regulating device 123 can achieve a change in the opening degree according to the opening degree regulating instruction, so that the electrolyte flow rate in the liquid inlet channel is consistent with the target flow rate. Among them, the flow rate regulating device 123 can be arranged in the liquid inlet channel and realized by using a flow rate regulating valve. It can be understood that the flow rate regulating valve mainly controls the constant flow rate based on controlling the constant pressure difference in the regulating section, that is, when the rated stroke of the valve changes from 0 to 100%, the flow rate through the valve will change correspondingly with the percentage rated stroke. Based on different flow rate regulating requirements, the flow rate regulating device 123 in the embodiment of the present application can be realized by using different flow rate regulating valves. For example, the flow rate regulating valve can be an electric regulating valve to automatically change the opening degree according to the opening degree regulating instruction. In some application scenarios, such as the product R & D test stage or when the product fails, the flow rate regulating valve can also include a manual balancing valve for manually adjusting the valve opening degree during use and recording the opening degree and the detected electrolyte flow rate to obtain the law of the valve opening degree and the electrolyte flow rate under different charge and discharge conditions.

[0077] In this embodiment, by setting a flow rate monitoring module on the electrode frame of a single cell, continuously monitoring the electrolyte flow rate of each single cell, and when an abnormal flow rate deviation is detected, the automatic regulating device responds and adjusts the opening degree of the liquid inlet channel to keep the flow rate of the single cells of the entire flow battery stable at the target flow rate.

[0078] In an exemplary embodiment, the number of liquid inlet channels is two or more. Specifically, the electrolyte flow channels flowing into the frame from the outside can be designed to distribute the flow rate in multiple stages, that is, the number of liquid inlet channels is set to be multiple to deliver the electrolyte to different parts of the electrode placement area, as much as possible to ensure that the electrolyte flows evenly in the electrode placement area, and then ensure that the electrolyte reacts fully. Among them, the number of liquid inlet channels can be set to two with reference to Figure 4 And 5 shown, or can be designed to be multiple according to actual technical requirements.

[0079] Correspondingly, in an exemplary embodiment, continue to refer to Figure 3 , the flow rate acquisition unit 121 is used to acquire the electrolyte flow rate of each liquid inlet channel, and after summarizing the total electrolyte flow rate, send it to the control module through the data transmission unit 122; the flow rate regulating device 123 is used to achieve a change in the opening degree according to the opening degree regulating instruction, so that the total electrolyte flow rate is consistent with the target flow rate.

[0080] Specifically, the flow rate acquisition unit 121 may include flow meters provided on multiple liquid inlet channels to acquire the electrolyte flow rates of the respective liquid inlet channels. It can be understood that the total electrolyte flow rate is the total amount of electrolyte flow rate flowing into the entire electrode frame, which can be obtained by summing up the electrolyte flow rates of the respective liquid inlet channels. The aggregated total electrolyte flow rate can be transmitted to the control module through the data transmission unit 122. Of course, the process of aggregating the total electrolyte flow rate based on the electrolyte flow rates of the respective liquid inlet channels may also be completed by the control module, and the data transmission unit 122 only needs to receive the electrolyte flow rates acquired by multiple flow meters and send them to the control module.

[0081] Further, when the number of liquid inlet channels provided in the electrode frame is two or more, the flow rate regulating device 123 may include flow rate regulating valves provided corresponding to each liquid inlet channel. Thus, the opening degree regulating instruction described in the embodiments of the present application can be understood as an opening degree regulating instruction for regulating the opening degree of each flow rate regulating valve.

[0082] It can be understood that after receiving the total electrolyte flow rate, the control module can perform deviation analysis between it and the target flow rate to obtain an opening degree regulating instruction. Taking the target regulating instruction as a directional instruction for regulating in a preset fixed step as an example, if the total electrolyte flow rate is greater than the target flow rate, then correspondingly, an opening degree regulating instruction for reducing the opening degree by a preset fixed step needs to be output for each flow rate regulating valve. If the total electrolyte flow rate is less than the target flow rate, then correspondingly, an opening degree regulating instruction for increasing the opening degree by a preset fixed step needs to be output for each flow rate regulating valve. In some other embodiments, if the total electrolyte flow rate is greater than the target flow rate and there are differences between the electrolyte flow rates of the respective liquid inlet channels, then correspondingly, an opening degree regulating instruction for reducing the opening degree by a preset fixed step can be output for the flow rate regulating valves corresponding to the top preset number of electrolyte flow rates sorted from large to small.

[0083] Even further, after the opening degree regulating instruction is sent to the corresponding flow rate regulating valve, the flow rate regulating valve can change the opening degree according to the opening degree regulating instruction, so that the total electrolyte flow rate flowing into the electrode frame is consistent with the target flow rate. Thereby ensuring the dynamic balance of the electrolyte flow rates of all single cells in the flow battery to improve the overall charge and discharge efficiency.

[0084] In an exemplary embodiment, continue to refer to Figure 3 as shown, the electrode frame further includes: a pressure monitoring unit 130 for acquiring the electrolyte pressure of the liquid inlet channel and sending the electrolyte pressure to the control module through the data transmission unit 122; the data transmission unit 122 is further configured to receive a shut-off instruction sent by the control module and transmit the shut-off instruction to the flow rate regulating device 123; the flow rate regulating device 123 is further configured to shut off the liquid inlet channel according to the shut-off instruction.

[0085] Specifically, the pressure monitoring unit 130 is a sensing component that collects the electrolyte pressure in the liquid inlet channel, capable of real-time sensing of changes in the electrolyte pressure and converting it into an electrical signal or other forms of signals for transmission and processing. The pressure monitoring unit 130 may specifically be a strain gauge sensor, a piezoelectric sensor, a piezoresistive sensor, an optical sensor, or the like.

[0086] Further, during the process of the control module outputting an opening adjustment instruction to adjust the electrolyte flow rate in the liquid inlet channel, the control module can also perform a pressure overlimit warning based on the electrolyte pressure in the liquid inlet channel sent by the data transmission unit 122. When the received electrolyte pressure exceeds the pressure protection threshold, the control module will output a shutdown instruction through the data transmission unit 122, causing the valve opening of the flow rate adjustment device 123 to change to 0%, controlling the shutdown of the liquid inlet channel, preventing the electrolyte with ultra-high pressure from flushing into the electrode frame, and preventing damage to the flow battery.

[0087] In an exemplary embodiment, please refer to Figure 6 , the flow rate monitoring module 120 is disposed on the side of the housing 100. It can be understood that the flow rate adjustment device 123 in the flow rate monitoring module 120 can be disposed on the side of the housing 100, and a knob-type manual balance valve is set by means of protruding installation, so as to facilitate the artificial adjustment of the valve opening during the product R & D test stage or when the product fails. And other parts can be communicatively disposed inside the housing 100, near the position of the liquid inlet channel.

[0088] In an exemplary embodiment, the housing further includes an electrolyte distribution area communicating with the liquid inlet channel, and the electrolyte distribution area is provided with a gradually widening flow guiding structure.

[0089] Specifically, as shown in Figure 1 , a multi-stage distribution channel can be set in the electrolyte distribution area AA. Distribution channel baffles can be set in each stage of the distribution channel to form a plurality of distribution ports for communicating the upper and lower stage distribution channels. Among them, along the flow direction of the electrolyte, the width of the distribution channel baffles on each stage of the distribution channel gradually decreases, and the number of distribution ports gradually increases, finally forming a gradually widening flow guiding structure.

[0090] In an exemplary embodiment, an electrolyte distribution method is provided, which is applied to the flow battery described in any of the above embodiments, and specifically can be applied to its control device. As shown in Figure 7 , the electrolyte distribution method includes the following steps 202 to step 206, where:

[0091] Step 202: Obtain the charge and discharge working conditions of the flow battery body and the electrolyte flow rates of each liquid inlet channel;

[0092] Step 204: Determine the target flow rate according to the charge and discharge working conditions of the flow battery body;

[0093] Step 206: Conduct deviation analysis based on the electrolyte flow rate and the target flow rate, and output an opening adjustment command.

[0094] Specifically, for the flow rate monitoring module on the electrode frame, after the flow rate monitoring module monitors the electrolyte flow rate of the liquid inlet channel, the control module can determine the target flow rate according to the charge and discharge conditions of the flow battery, and then, based on the deviation analysis of the electrolyte flow rate and the target flow rate of each liquid inlet channel obtained, output an opening adjustment command to adjust the opening of the liquid inlet channel.

[0095] Among them, when the control module obtains the target flow rate, it can first obtain the battery voltage of the flow battery body, then determine the target charge and discharge stage where the flow battery body is located based on the battery voltage, and finally determine the target flow rate corresponding to the target charge and discharge stage. For the embodiments of the present application, to ensure that the electrolyte of each single cell reacts sufficiently, the above-determined target flow rate is the target flow rate required for the sufficient reaction of the single cell, and is used to control the opening of the liquid inlet channel on the electrode frame of the single cell. In addition, to achieve the dynamic balance of the electrolyte flow rate in all single cells in the flow battery, the target flow rates determined for the same target charge and discharge stage of all single cells in the present application embodiments are the same. Of course, in some embodiments, for the operation requirements of the flow battery, the target flow rates determined for the same target charge and discharge stage of multiple single cells can also be set to different flow rate values.

[0096] Furthermore, the manner in which the control module outputs the opening adjustment command is not unique. It can be to calculate the flow rate deviation value between the electrolyte flow rate and the target flow rate, and then output the opening adjustment command according to the corresponding relationship between the flow rate deviation value and the opening of the liquid inlet channel, so as to use fewer adjustment times to make the electrolyte flow rate reach the same as the target flow rate. It can also be to determine the opening adjustment direction of the liquid inlet channel based on the deviation analysis of the electrolyte flow rate and the target flow rate, and then output a directional command for adjustment with a preset fixed step length until the electrolyte flow rate reaches the same as the target flow rate. For example, when it is analyzed that the electrolyte flow rate is greater than the target flow rate, output a command to reduce the opening of the liquid inlet channel with a preset fixed step length; when it is analyzed that the electrolyte flow rate is less than the target flow rate, output a command to increase the opening of the liquid inlet channel with a preset fixed step length. Of course, when it is determined based on the deviation analysis of the electrolyte flow rate and the target flow rate that the electrolyte flow rate has reached the same as the target flow rate, it can be not to output the opening adjustment command, or to output an opening adjustment command to keep the opening unchanged.

[0097] In this embodiment, by determining the target flow rate based on the charge and discharge conditions of the flow battery body, the opening control of the liquid inlet channel is realized, providing high flexibility for the control of the electrolyte flow rate of the flow battery under different working states.

[0098] In an exemplary embodiment, as Figure 8 shown, determining the target flow rate according to the charge and discharge conditions of the flow battery body in step 202 includes the following steps 302 to 306, where:

[0099] Step 302: Obtain the battery voltage of the flow battery body;

[0100] Step 304: Determine the target charge and discharge stage in which the flow battery body is located based on the battery voltage;

[0101] Step 306: Determine the target flow rate corresponding to the target charge and discharge stage.

[0102] Specifically, according to the charge and discharge characteristics of the flow battery, the battery voltage can be divided into multiple charge and discharge stages from low to high in advance. Among them, the charge stage and the discharge stage corresponding to the same battery voltage can be the same or different, which is determined according to the parameters of the actual flow battery. Furthermore, in the actual adjustment process, after obtaining the actual battery voltage of the flow battery body, the target charge and discharge stage in which the flow battery body is located can be determined based on the battery voltage, and then the flow target value corresponding to the target charge and discharge stage is determined as the target flow rate.

[0103] It can be understood that the division of the charge and discharge stages and their corresponding flow target values can be determined in advance according to the pre-test data in the early product test stage. Taking the charge stage as an example, the battery voltage can be divided into three charge stages from low to high according to the pre-test: a-b, b-c, c-d. And according to the pre-test, the flow target value corresponding to the a-b charge stage is set as value A, the flow target value corresponding to the b-c charge stage is set as value B, and the flow target value corresponding to the c-d charge stage is set as value C. Furthermore, in the actual adjustment process, if the actual battery voltage is in the a-b charge stage, the target flow rate can be determined as value A, and so on.

[0104] In an exemplary embodiment, as Figure 9 shown, the above electrolyte distribution method further includes the following steps 402 to 404, where:

[0105] Step 402: Obtain the electrolyte pressure of each inlet flow channel;

[0106] Step 404: Output a shutdown instruction when the electrolyte pressure exceeds the pressure protection threshold.

[0107] Specifically, the pressure monitoring unit is a sensing component that collects the electrolyte pressure in the liquid inlet flow channel, capable of real-time sensing of changes in the electrolyte pressure and converting it into an electrical signal or other form of signal for transmission and processing. The pressure monitoring unit can specifically be a strain gauge sensor, a piezoelectric sensor, a piezoresistive sensor, an optical sensor, etc.

[0108] Further, during the process of the control module outputting an opening adjustment instruction to adjust the electrolyte flow rate in the liquid inlet flow channel, the control module can also perform a pressure overlimit warning based on the electrolyte pressure in the liquid inlet flow channel sent by the data transmission unit. When the received electrolyte pressure exceeds the pressure protection threshold, the control module will output a shutdown instruction through the data transmission unit, causing the valve opening of the flow rate adjustment device to change to 0%, controlling the shutdown of the liquid inlet flow channel, preventing the electrolyte with ultra-high pressure from flushing into the electrode frame, and preventing damage to the flow battery.

[0109] It can be understood that the implementation solutions for solving problems provided by this electrolyte distribution method are similar to the implementation solutions described in the above flow battery and its electrode frame. Therefore, the specific limitations in one or more of the above electrolyte distribution method embodiments can refer to the limitations on the flow battery and its electrode frame in the foregoing text, and will not be elaborated here.

[0110] It should be understood that although the steps in the flowcharts involved in the above-described embodiments are shown in sequence according to the arrows, these steps are not necessarily executed in the order indicated by the arrows. Unless there is a clear description in this article, the execution of these steps has no strict order limitation, and these steps can be executed in other orders. Moreover, at least a part of the steps in the flowcharts involved in the above-described embodiments may include multiple steps or multiple stages. These steps or stages are not necessarily executed at the same moment, but can be executed at different moments. The execution order of these steps or stages is not necessarily sequential either, but can be executed alternately or in turn with at least a part of the steps or stages in other steps or other steps.

[0111] The technical features of the above embodiments can be combined arbitrarily. For the sake of concise description, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, it should be considered as within the scope recorded in this application.

[0112] The above-described embodiments merely represent several implementation manners of the present application. The description thereof is relatively specific and detailed, but it should not be construed as a limitation to the patent scope of the present application. It should be noted that for those of ordinary skill in the art, without departing from the concept of the present application, several modifications and improvements can still be made, and these all fall within the protection scope of the present application. Therefore, the protection scope of the present application shall be subject to the appended claims.

Claims

1. An electrode frame of a liquid flow battery, applied to a liquid flow battery comprising a plurality of single-chip batteries connected in series, each of the single-chip batteries comprising at least a positive electrode, a negative electrode and a separator, the positive electrode and the negative electrode are respectively embedded in the corresponding electrode frame; It is characterized in that The electrode frame comprises: A frame, the frame comprising an inlet channel and an outlet channel for circulating electrolyte; A flow monitoring module is provided in the frame, and is used to monitor the electrolyte flow in the liquid inlet channel and regulate the electrolyte flow to be consistent with a target flow, wherein the target flow is determined according to the charge and discharge conditions of the liquid flow battery.

2. The electrode frame according to claim 1, characterized in that: The flow monitoring module includes a flow collection unit, a data transmission unit and a flow regulating device, the flow collection unit is connected to the data transmission unit, the data transmission unit is connected to the control module of the flow battery, and the data transmission unit is also connected to the flow regulating device; The flow collection unit is used to collect the electrolyte flow of the liquid inlet channel and send the electrolyte flow to the control module through the data transmission unit; The data transmission unit is further used to receive the opening adjustment instruction sent by the control module, and transmit the opening adjustment instruction to the flow regulating device; The flow regulating device is used to change the opening according to the opening regulating instruction so as to make the electrolyte flow rate consistent with the target flow rate.

3. The electrode frame according to claim 2, characterized in that: The number of the liquid inlet flow channels is two or more; The flow collection unit is used to collect the electrolyte flow of each inlet flow channel, summarize the total electrolyte flow, and then send it to the control module through the data transmission unit; The flow regulating device is used to change the opening according to the opening regulating instruction so as to make the total electrolyte flow consistent with the target flow.

4. The electrode frame according to claim 2, characterized in that: The electrode frame also includes: A pressure monitoring unit, used for collecting and obtaining the electrolyte pressure of the liquid inlet channel, and sending the electrolyte pressure to the control module through the data transmission unit; The data transmission unit is further used to receive a shut-down instruction sent by the control module, and transmit the shut-down instruction to the flow regulating device; The flow regulating device is also used to shut off the liquid inlet channel according to the shut-off instruction.

5. The electrode frame according to claim 1, characterized in that: The flow monitoring module is arranged on the side of the frame.

6. The electrode frame according to any one of claims 1 to 5, characterized in that: The frame also includes an electrolyte distribution area connected to the liquid inlet channel, and the electrolyte distribution area is provided with a gradually widening flow guide structure.

7. A liquid flow battery, characterized in that: The liquid flow battery comprises a liquid flow battery body and a control module, wherein the control module is connected to the liquid flow battery body; The flow battery body comprises a plurality of single-chip batteries connected in series, each of the single-chip batteries comprises at least a positive electrode, a negative electrode and a separator, and the positive electrode and the negative electrode are respectively embedded in the electrode frame according to any one of claims 1 to 6; The control module is used to determine the target flow rate according to the charge and discharge conditions of the liquid flow battery body, and obtain the electrolyte flow rate of each liquid inlet channel monitored by the electrode frame, and output the opening adjustment instruction according to the deviation analysis between the electrolyte flow rate and the target flow rate.

8. An electrolyte distribution method, characterized in that: The method comprises: Obtaining the charge and discharge conditions of the flow battery body and the electrolyte flow rate of each liquid inlet flow channel; Determining a target flow rate according to the charge and discharge conditions of the flow battery body; Deviation analysis is performed based on the electrolyte flow rate and the target flow rate, and an opening adjustment instruction is output.

9. The electrolyte distribution method according to claim 8, characterized in that: The step of determining the target flow rate according to the charging and discharging conditions of the flow battery body comprises: Obtaining the battery voltage of the flow battery body; Determining a target charge and discharge stage of the flow battery body based on the battery voltage; Determine the target flow rate corresponding to the target charging and discharging stage.

10. The electrolyte distribution method according to claim 8, characterized in that: The method further comprises: Obtaining the electrolyte pressure of each liquid inlet flow channel; When the electrolyte pressure exceeds the pressure protection threshold, a shutdown command is output.

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