Flow battery system

Abstract

The invention discloses a flow battery system. The flow battery system comprises a positive electrode electrolyte tank, a negative electrode electrolyte tank, a plurality of battery modules and a plurality of SOC sub-detection devices, a positive electrode electrolyte supply branch and a positive electrode electrolyte backflow branch are respectively connected between the positive electrode electrolyte tank and each battery module; a negative electrode electrolyte supply branch and a negative electrode electrolyte backflow branch are connected between the negative electrode electrolyte tank and each battery module, a first control valve is arranged on the positive electrode electrolyte supply branch, and a second control valve is arranged on the negative electrode electrolyte supply branch; each SOC sub-detection device is set to detect the SOC value of one battery module, and when the SOC sub-detection device detects that the SOC value of the corresponding battery module reaches a preset value, the first control valve and the second control valve corresponding to the battery module are closed. According to the scheme provided by the invention, the problem of over-charging or over-discharging of the battery module can be solved.

Description

Technical Field

[0001] The present invention relates to the field of battery technology, and in particular to a liquid flow battery system. Background Art

[0002] The liquid flow battery system includes multiple battery modules. The liquid flow battery system will only display full charge when all battery modules are fully charged. However, due to the different resistances of each battery module, the battery modules will not be fully charged at the same time, which will cause some battery modules to be overcharged. Similarly, the battery modules will not be fully discharged at the same time, which will cause some battery modules to be over-discharged.

[0003] Overcharging a battery may increase the internal pressure of the battery, causing the battery shell to rupture or even explode. Long-term overcharging will cause the active materials in the battery to fall off, resulting in a decrease in the actual available capacity of the battery. The battery will age faster when overcharged, thus shortening the battery life. When overcharged, excessive heat may be generated inside the battery, leading to thermal runaway and further damage to the battery. Overdischarging a battery will cause some active materials to lose their activity, resulting in permanent loss of battery capacity. Frequent overdischarging will accelerate battery aging and reduce the number of battery charge and discharge cycles. After a battery is overdischarged, its internal impedance will increase, causing the battery to generate more heat during discharge and reduce efficiency. The battery may experience voltage instability when overdischarged, affecting the normal use of the device.

[0004] Therefore, it is necessary to provide a solution to solve the problem of overcharging or over-discharging of some battery modules in the current liquid flow battery system. Summary of the invention

[0005] The embodiment of the present application provides a liquid flow battery system to solve the problem of overcharging or over-discharging of some battery modules in the current liquid flow battery system.

[0006] An embodiment of the present application provides a flow battery system, comprising: a positive electrode electrolyte tank, a negative electrode electrolyte tank, a plurality of battery modules, and a plurality of SOC sub-detection devices; A positive electrolyte supply branch and a positive electrolyte reflux branch are respectively connected between the positive electrolyte tank and each of the battery modules, the positive electrolyte supply branch is configured to supply positive electrolyte to the battery module, and the positive electrolyte of the battery module flows back to the positive electrolyte tank through the positive electrolyte reflux branch; a negative electrolyte supply branch and a negative electrolyte reflux branch are respectively connected between the negative electrolyte tank and each of the battery modules, the negative electrolyte supply branch is configured to supply negative electrolyte to the battery module, and the negative electrolyte of the battery module flows back to the negative electrolyte tank through the negative electrolyte reflux branch; wherein a first control valve for controlling the on-off of the pipeline is provided on the positive electrolyte supply branch, and a second control valve for controlling the on-off of the pipeline is provided on the negative electrolyte supply branch; Each of the SOC sub-detection devices is configured to detect the SOC value of one of the battery modules. When the SOC sub-detection device detects that the SOC value of the corresponding battery module reaches a preset value, the first control valve and the second control valve corresponding to the battery module are closed.

[0007] In one embodiment, a third control valve is provided on the positive electrode electrolyte reflux branch, and a fourth control valve is provided on the negative electrode electrolyte reflux branch; When the SOC sub-detection device detects that the SOC value of the corresponding battery module reaches a preset value, the third control valve and the fourth control valve corresponding to the battery module are disconnected.

[0008] In one embodiment, the positive electrolyte supply branch is connected to a positive electrolyte bypass flow path between a position upstream of the first control valve and the positive electrolyte tank, and a fifth control valve for controlling the on-off of the pipeline is provided on the positive electrolyte bypass flow path; The negative electrolyte supply branch is connected with a negative electrolyte bypass flow path between the position upstream of the second control valve and the negative electrolyte tank, and a sixth control valve for controlling the on-off of the pipeline is arranged on the negative electrolyte bypass flow path; When the SOC sub-detection device detects that the SOC value of the corresponding battery module reaches a preset value, the fifth control valve and the sixth control valve corresponding to the battery module are opened.

[0009] In one embodiment, each of the SOC sub-detection devices has a positive electrode electrolyte inlet, a negative electrode electrolyte inlet, a positive electrode electrolyte outlet, and a negative electrode electrolyte outlet; A first detection flow path is connected between the positive electrode electrolyte inlet and the corresponding positive electrode electrolyte supply branch, a second detection flow path is connected between the negative electrode electrolyte inlet and the corresponding negative electrode electrolyte supply branch, a third detection flow path is connected between the positive electrode electrolyte outlet and the positive electrode electrolyte tank, and a fourth detection electrolyte flow path is connected between the negative electrode electrolyte outlet and the negative electrode electrolyte tank; A seventh control valve is arranged on the first detection flow path, and an eighth control valve is arranged on the second detection flow path; when the SOC sub-detection device detects that the SOC value of the corresponding battery module reaches a preset value, the seventh control valve and the eighth control valve corresponding to the battery module are disconnected.

[0010] In one embodiment, the liquid flow battery system further includes a total SOC detection device, and the total SOC detection device is configured to detect the SOC value of the liquid flow battery system.

[0011] In one embodiment, the positive electrode electrolyte tank is connected to a positive electrode electrolyte supply main flow path, and the negative electrode electrolyte tank is connected to a negative electrode electrolyte supply main flow path; a plurality of positive electrode electrolyte supply branches are connected to the positive electrode electrolyte supply main flow path, and a plurality of negative electrode electrolyte supply branches are connected to the negative electrode electrolyte supply main flow path; The SOC total detection device has a positive electrode electrolyte total inlet, a positive electrode electrolyte total outlet, a negative electrode electrolyte total inlet and a negative electrode electrolyte total outlet. The positive electrode electrolyte total inlet is connected to the positive electrode electrolyte supply total flow path, the negative electrode electrolyte total inlet is connected to the negative electrode electrolyte supply total flow path, a positive electrode electrolyte circuit is connected between the positive electrode electrolyte total outlet and the positive electrode electrolyte tank, and a negative electrode electrolyte circuit is connected between the negative electrode electrolyte outlet and the negative electrode electrolyte tank.

[0012] In one embodiment, a water pump and a control valve for controlling the on-off of the pipeline are provided on the main flow path for supplying the positive electrode electrolyte; and a water pump and a control valve for controlling the on-off of the pipeline are provided on the main flow path for supplying the negative electrode electrolyte.

[0013] In one embodiment, a positive electrode connection flow path is connected to the positive electrode electrolyte supply main flow path and between the water pump and the SOC main detection device, and a plurality of positive electrode electrolyte supply branches are connected to the positive electrode connection flow path; A negative electrode connection flow path is connected to the negative electrode electrolyte supply main flow path and between the water pump and the SOC main detection device, and the plurality of negative electrode electrolyte supply branches are all connected to the negative electrode connection flow path.

[0014] In one embodiment, there are two preset values, one of which is a first preset value indicating that the battery module is fully charged, and the other preset value is a second preset value indicating that the battery module is fully discharged.

[0015] The technical solution provided by the embodiments of the present application can effectively solve the problem of overcharging or over-discharging of some battery modules in the liquid flow battery system in the prior art, improve the consistency and balance of charging of each battery module, so that the liquid flow battery system has better stability, which is beneficial to improving the utilization efficiency of the battery and reducing the occurrence of battery failure.

[0016] Other features and advantages of the present application will be described in the following description, and partly become apparent from the description, or be understood by implementing the present application. Other advantages of the present application can be realized and obtained by the schemes described in the description and the drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] The accompanying drawings are used to provide an understanding of the technical solution of the present application and constitute a part of the specification. Together with the embodiments of the present application, they are used to explain the technical solution of the present application and do not constitute a limitation on the technical solution of the present application.

[0018] Figure 1 A schematic diagram of the structure of a liquid flow battery system according to an embodiment of the present application; Figure 2 The present invention is a flow chart of a charging or discharging process of a liquid flow battery system according to one embodiment of the present application.

[0019] Description of reference numerals: 1-positive electrolyte tank; 2-negative electrolyte tank; 3-water pump; 4-SOC total detection device; 5-battery module; 51-positive electrolyte supply branch; 52-negative electrolyte supply branch; 53-positive electrolyte return branch; 54-negative electrolyte return branch; 55-first control valve; 56-second control valve; 57-third control valve; 58-fourth control valve; 6-SOC sub-detection device; 61-first detection flow path; 62-second detection flow path Path; 63-third detection flow path; 64-fourth detection flow path; 65-seventh control valve; 66-eighth control valve; 7-total positive electrode electrolyte supply flow path; 8-total negative electrode electrolyte supply flow path; 9-positive electrode connection flow path; 10-negative electrode connection flow path; 11-positive electrode electrolyte loop; 12-negative electrode electrolyte loop; 13-positive electrode electrolyte side branch flow path; 14-fifth control valve; 15-negative electrode electrolyte side branch flow path; 16-sixth control valve; 17-control valve. DETAILED DESCRIPTION

[0020] The present application describes multiple embodiments, but the description is exemplary rather than restrictive, and it is obvious to those skilled in the art that there may be more embodiments and implementations within the scope of the embodiments described in the present application. Although many possible feature combinations are shown in the drawings and discussed in the specific embodiments, many other combinations of the disclosed features are also possible. Unless specifically limited, any feature or element of any embodiment may be used in combination with any other feature or element in any other embodiment, or may replace any other feature or element in any other embodiment.

[0021] The present application includes and contemplates combinations of features and elements known to those of ordinary skill in the art. The embodiments, features and elements disclosed in the present application may also be combined with any conventional features or elements to form a unique invention scheme. Any features or elements of any embodiment may also be combined with features or elements from other invention schemes to form another unique invention scheme. Therefore, it should be understood that any feature shown and / or discussed in the present application may be implemented individually or in any appropriate combination. Therefore, except for the limitations made according to the attached claims and their equivalents, the embodiments are not subject to other restrictions. In addition, various modifications and changes may be made within the scope of protection of the attached claims.

[0022] In addition, when describing representative embodiments, the specification may have presented the method and / or process as a specific sequence of steps. However, to the extent that the method or process does not rely on the specific order of the steps described herein, the method or process should not be limited to the steps of the specific order described. As will be understood by those of ordinary skill in the art, other sequences of steps are also possible. Therefore, the specific sequence of the steps set forth in the specification should not be interpreted as a limitation to the claims. In addition, the claims for the method and / or process should not be limited to the steps of performing them in the order written, and those skilled in the art can easily understand that these sequences can be changed and still remain within the spirit and scope of the embodiments of the present application.

[0023] The embodiment of the present application provides a flow battery system, such as Figure 1 As shown, it includes: a positive electrode electrolyte tank 1, a negative electrode electrolyte tank 2, a plurality of battery modules 5 and a plurality of SOC sub-detection devices 6.

[0024] A positive electrolyte supply branch 51 and a positive electrolyte return branch 53 are respectively connected between the positive electrolyte tank 1 and each battery module 5. The positive electrolyte supply branch 51 is configured to supply positive electrolyte to the battery module 5, and the positive electrolyte of the battery module 5 flows back to the positive electrolyte tank 1 through the positive electrolyte return branch 53; a negative electrolyte supply branch 52 and a negative electrolyte return branch 54 are respectively connected between the negative electrolyte tank 2 and each battery module 5. The negative electrolyte supply branch 52 is configured to supply negative electrolyte to the battery module 5, and the negative electrolyte of the battery module 5 flows back to the negative electrolyte tank 2 through the negative electrolyte return branch 54. A first control valve 55 for controlling the on-off of the pipeline is provided on the positive electrolyte supply branch 51, and a second control valve 56 for controlling the on-off of the pipeline is provided on the negative electrolyte supply branch 52; Each SOC sub-detection device 6 is configured to detect the SOC value of a battery module 5. When the SOC sub-detection device 6 detects that the SOC value of the corresponding battery module 5 reaches a preset value, the first control valve 55 and the second control valve 56 corresponding to the battery module 5 are closed.

[0025] The preset value may be a first preset value indicating that the battery module 5 is fully charged, or a second preset value indicating that the battery module 5 is fully discharged. The first preset value is usually 100%, and the second preset value is usually 0%. Of course, the preset value may also be set to other values ​​indicating full charge or discharge.

[0026] Figure 1 Two battery modules 5 are shown in the figure, and more battery modules 5 can be set. When a battery module 5 is fully charged, the SOC sub-detection device 6 corresponding to the battery module 5 detects that the SOC value reaches 100%, then the first control valve 55 and the second control valve 56 corresponding to the battery module 5 are closed, the positive electrolyte supply branch 51 stops supplying positive electrolyte to the battery module 5, and the negative electrolyte supply branch 52 stops supplying negative electrolyte to the battery module 5, and the battery module 5 stops charging, thereby preventing the battery module 5 from being overcharged.

[0027] Similarly, when a battery module 5 is fully discharged, the SOC sub-detection device 6 corresponding to the battery module 5 detects that the SOC value reaches 0%, then the first control valve 55 and the second control valve 56 corresponding to the battery module 5 are closed, the positive electrolyte supply branch 51 stops supplying positive electrolyte to the battery module 5, and the negative electrolyte supply branch 52 stops supplying negative electrolyte to the battery module 5, and the battery module 5 stops discharging, thereby preventing the battery module from being over-discharged.

[0028] It is understandable that two preset values ​​can be set, one of which is a first preset value indicating that the battery module 5 is fully charged, and the other is a second preset value indicating that the battery module 5 is fully discharged. Thus, charging can be stopped when the SOC value reaches the first preset value, and discharging can be stopped when the SOC value reaches the second preset value.

[0029] Therefore, the technical solution provided in the present application can effectively solve the problem of overcharging or over-discharging of some battery modules in the liquid flow battery system in the prior art, improve the consistency and balance of charging of each battery module, so that the liquid flow battery system can have better stability, which is beneficial to improving the utilization efficiency of the battery and reducing the occurrence of battery failure.

[0030] In one embodiment, Figure 1 As shown, a third control valve 57 is provided on the positive electrolyte return branch 53, and a fourth control valve 58 is provided on the negative electrolyte return branch 54; when each SOC sub-detection device 6 detects that the SOC value of the corresponding battery module 5 reaches a preset value, the third control valve 57 and the fourth control valve 58 corresponding to the battery module 5 are disconnected.

[0031] In one embodiment, Figure 1 As shown, the positive electrolyte supply branch 51 is connected to a positive electrolyte bypass flow path 13 between a position upstream of the first control valve 55 and the positive electrolyte tank 1, and a fifth control valve 14 for controlling the on-off of the pipeline is arranged on the positive electrolyte bypass flow path 13; the negative electrolyte supply branch 52 is connected to a negative electrolyte bypass flow path 15 between a position upstream of the second control valve 56 and the negative electrolyte tank 2, and a sixth control valve 16 for controlling the on-off of the pipeline is arranged on the negative electrolyte bypass flow path 15.

[0032] When the SOC sub-detection device 6 detects that the SOC value of the corresponding battery module 5 reaches a preset value, the fifth control valve 14 and the sixth control valve 16 corresponding to the battery module 5 are opened, so that the positive electrolyte bypass flow path 13 and the negative electrolyte bypass flow path 15 are opened. In this way, when the connection between the positive electrolyte supply branch 51 and the battery module 5 is disconnected and the connection between the negative electrolyte supply branch 52 and the battery module 5 is disconnected, the electrolyte flowing to the positive electrolyte supply branch 51 will flow back from the positive electrolyte bypass flow path 13 to the positive electrolyte tank 1, and the electrolyte flowing to the negative electrolyte supply branch 52 will flow back from the negative electrolyte bypass flow path 15 to the negative electrolyte tank 2.

[0033] In one embodiment, each SOC sub-detection device 6 has a positive electrolyte inlet, a negative electrolyte inlet, a positive electrolyte outlet and a negative electrolyte outlet; a first detection flow path 61 is connected between the positive electrolyte inlet and the positive electrolyte supply branch 51, a second detection flow path 62 is connected between the negative electrolyte inlet and the corresponding negative electrolyte supply branch 52, a third detection flow path 63 is connected between the positive electrolyte outlet and the positive electrolyte tank 1, and a fourth detection flow path 64 is connected between the negative electrolyte outlet and the negative electrolyte tank 2.

[0034] That is, a reference battery is provided in the SOC sub-detection device 6, and the electrolyte is circulated between the reference battery and the electrolyte tank through the first detection flow path 61, the second detection flow path 62, the third detection flow path 63 and the fourth detection flow path 64 to detect the SOC value, and the SOC value of the corresponding battery module 5 is obtained through the reference battery of the SOC sub-detection device 6. The specific working principle is known to those skilled in the art and will not be described in detail here. It is understandable that the SOC value can also be detected in other ways.

[0035] A seventh control valve 65 is provided on the first detection flow path 61, and an eighth control valve 66 is provided on the second detection flow path 62; when the SOC sub-detection device 6 detects that the SOC value of the corresponding battery module 5 reaches a preset value, the seventh control valve 65 and the eighth control valve 66 corresponding to the battery module 5 are disconnected, that is, the electrolyte will not continue to flow in the SOC sub-detection device 6.

[0036] In addition, control valves may also be provided on the third detection flow path 63 and the fourth detection flow path 64 to facilitate disconnection of the pipelines when the SOC sub-detection device 6 is replaced.

[0037] In one embodiment, the liquid flow battery system further includes a total SOC detection device 4, and the total SOC detection device 4 is configured to detect the SOC value of the liquid flow battery system.

[0038] like Figure 1 As shown, the positive electrode electrolyte tank 1 is connected to the positive electrode electrolyte supply main flow path 7, and the negative electrode electrolyte tank 2 is connected to the negative electrode electrolyte supply main flow path 8; multiple positive electrode electrolyte supply branches 51 are connected to the positive electrode electrolyte supply main flow path 7, and multiple negative electrode electrolyte supply branches 52 are connected to the negative electrode electrolyte supply main flow path 8.

[0039] The SOC total detection device 4 has a total positive electrolyte inlet, a total positive electrolyte outlet, a total negative electrolyte inlet and a total negative electrolyte outlet. The total positive electrolyte inlet is connected to the total positive electrolyte supply flow path 7, the total negative electrolyte inlet is connected to the total negative electrolyte supply flow path 8, a positive electrolyte loop 11 is connected between the total positive electrolyte outlet and the positive electrolyte tank 1, and a negative electrolyte loop 12 is connected between the total negative electrolyte outlet and the negative electrolyte tank 2.

[0040] The principle of obtaining the SOC value by the SOC total detection device 4 and the SOC sub-detection device 6 is the same, and the detection of the SOC value of the flow battery system is also achieved by circulating the electrolyte between the SOC total detection device 4 and the electrolyte tank.

[0041] When each battery module 5 is fully charged, that is, when the SOC value of each battery module reaches, for example, 100%, the SOC value detected by the total SOC detection device 4 can reach 100%. At this time, the liquid flow battery system is fully charged. Since some battery modules 5 in this application will be in a disconnected state after being fully charged and charging will stop, overcharging of some battery modules 5 will not occur.

[0042] Similarly, when each battery module is in a fully discharged state, that is, when the SOC value of each battery module 5 reaches, for example, 0%, the SOC value detected by the total detection device 4 can reach 0%. At this time, the liquid flow battery system is fully discharged. Since some battery modules 5 in the present application will be in a disconnected state and stop discharging after the discharge is completed, over-discharge of some battery modules 5 will not occur.

[0043] In one embodiment, in order to make the positive electrolyte supply main flow path 7 supply positive electrolyte to each battery module 5, and the negative electrolyte supply main flow path 8 supply negative electrolyte to each battery module 5, a water pump 3 is respectively provided on the positive electrolyte supply main flow path 7 and the negative electrolyte supply main flow path 8, and the electrolyte circulation power is provided by the water pump 3. The positive electrolyte supply main flow path 7 and the negative electrolyte supply main flow path 8 can also be respectively provided with a control valve 17 for controlling the on-off of the pipeline.

[0044] In order to facilitate the connection between the positive electrode electrolyte supply main flow path 7 and each positive electrode electrolyte supply branch 51, a positive electrode connection flow path 9 is connected to the positive electrode electrolyte supply main flow path 7 and between the water pump 3 and the SOC total detection device 4. Multiple positive electrode electrolyte supply branches 51 are all connected to the positive electrode connection flow path 9, and the positive electrode electrolyte is supplied to each positive electrode electrolyte supply branch 51 through the positive electrode connection flow path 9.

[0045] A negative electrode connection flow path 10 is connected to the negative electrode electrolyte supply main flow path 8 and between the water pump 3 and the SOC total detection device 4. A plurality of negative electrode electrolyte supply branches 52 are all connected to the negative electrode connection flow path 10, and the negative electrode electrolyte is supplied to each negative electrode electrolyte supply branch 52 through the negative electrode connection flow path 10.

[0046] According to the following Figure 1 The flow battery system shown in the figure describes the specific process of charging and discharging.

[0047] When the liquid flow battery system starts charging each battery module 5 (it can also be discharging, charging is taken as an example here), the fifth control valve 14 and the sixth control valve 16 corresponding to each battery module 5 are closed, the first control valve 55, the second control valve 56, the third control valve 57, the fourth control valve 58 are opened, and the control valve 17 on the positive electrode electrolyte supply main flow path 7 and the negative electrode electrolyte supply main flow path 8 is opened, the water pump 3 is turned on, and the positive electrode electrolyte in the positive electrode electrolyte tank 1 is discharged through the positive electrode electrolyte supply main flow path 7, the positive electrode connection flow path 9 and each positive electrode electrolyte supply. The supply branch 51 flows to the positive electrode chamber of each battery module 5, and the positive electrode electrolyte in the battery module 5 is then refluxed to the positive electrode electrolyte tank 1 through the positive electrode electrolyte reflux branch 53; similarly, the negative electrode electrolyte in the negative electrode electrolytic tank 2 flows to the negative electrode chamber of each battery module 5 through the negative electrode electrolyte supply total flow path 8, the negative electrode connection flow path 10 and each negative electrode electrolyte supply branch 52, and the negative electrode electrolyte in the battery module 5 is then refluxed to the negative electrode electrolyte tank 2 through the negative electrode electrolyte reflux branch 54, and the electrolyte circulates, thereby realizing the charging of each battery module 5.

[0048] References Figure 2 Each SOC sub-detection device 6 detects the SOC value of each corresponding battery module 5, and the SOC total detection device 4 detects the SOC value of the entire liquid flow battery system.

[0049] During the operation of the liquid flow battery system, if the SOC values ​​detected by each SOC sub-detection device 6 are the same, the electrolyte of each battery module 5 circulates normally until the SOC value of the SOC total detection device 4 shows that it is full.

[0050] If the SOC values ​​detected by the various SOC sub-detection devices 6 are different during the operation of the liquid flow battery system, then after the system has been running for a period of time, when the SOC values ​​of some battery modules 5 are shown to be full (for example, the SOC reaches 100%), while the SOC values ​​of other battery modules 5 are not shown to be full, at this time, the first control valve 55, the second control valve 56, the third control valve 57 and the fourth control valve 58 corresponding to the battery module 5 that has been charged are closed, and the battery module 5 stops charging, while the fifth control valve 14 and the sixth control valve 16 corresponding to the battery module 5 are opened, so that the positive electrode electrolyte flowing to the battery module 5 flows back from the positive electrode electrolyte bypass flow path 13 to the positive electrode electrolyte tank 1, and the negative electrode electrolyte flowing to the battery module 5 flows back from the negative electrode electrolyte bypass flow path 15 to the negative electrode electrolyte tank 2.

[0051] The other battery modules 5 that are not fully charged continue to charge until the SOC values ​​of all the SOC sub-detection devices 6 show that they are fully charged. At this time, the SOC value of the SOC total detection device 4 also shows that it is fully charged. Therefore, the liquid flow battery system is fully charged.

[0052] Similarly, the discharge process of the liquid flow battery system is similar to the charging process, which will not be described here.

[0053] In the description of the present application, it should be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", "clockwise", "counterclockwise", "axial", "radial", "circumferential" and the like indicate orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present application and simplifying the description, and do not indicate or imply that the referred device or element must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as a limitation on the present application.

[0054] In addition, the terms "first", "second", etc. are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Thus, a feature defined as "first", "second", etc. may explicitly or implicitly include at least one of the features.

[0055] In the description of the present application, “plurality” means at least two, such as two, three, etc., unless otherwise clearly and specifically defined.

[0056] In this application, unless otherwise clearly specified and limited, the terms "installed", "connected", "connected", "fixed", etc. should be understood in a broad sense. For example, "connected" can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; 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 this application can be understood according to specific circumstances.

[0057] In the present application, unless otherwise clearly specified and limited, a first feature being “above” or “below” a second feature may mean that the first and second features are in direct contact, or the first and second features are in indirect contact through an intermediate medium. Moreover, a first feature being “above”, “above”, and “above” a second feature may mean that the first feature is directly above or obliquely above the second feature, or simply means that the first feature is higher in level than the second feature. A first feature being “below”, “below”, and “below” a second feature may mean that the first feature is directly below or obliquely below the second feature, or simply means that the first feature is lower in level than the second feature.

[0058] In the description of this specification, the description with reference to the terms "one embodiment", "some embodiments", "example", "specific example" or "some examples" etc. means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present application. In this specification, the schematic representations of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described may be combined in any one or more embodiments or examples in a suitable manner. In addition, those skilled in the art may combine and combine the different embodiments or examples described in this specification and the features of the different embodiments or examples, without contradiction.

[0059] Although the embodiments of the present application have been shown and described above, it can be understood that the above embodiments are exemplary and cannot be understood as limitations on the present application. Ordinary technicians in this field can change, modify, replace and modify the above embodiments within the scope of the present application.

Claims

1. A liquid flow battery system, characterized in that: include: A positive electrode electrolyte tank, a negative electrode electrolyte tank, a plurality of battery modules, and a plurality of SOC sub-detection devices; A positive electrolyte supply branch and a positive electrolyte reflux branch are respectively connected between the positive electrolyte tank and each of the battery modules, the positive electrolyte supply branch is configured to supply positive electrolyte to the battery module, and the positive electrolyte of the battery module flows back to the positive electrolyte tank through the positive electrolyte reflux branch; a negative electrolyte supply branch and a negative electrolyte reflux branch are respectively connected between the negative electrolyte tank and each of the battery modules, the negative electrolyte supply branch is configured to supply negative electrolyte to the battery module, and the negative electrolyte of the battery module flows back to the negative electrolyte tank through the negative electrolyte reflux branch; wherein a first control valve for controlling the on-off of the pipeline is provided on the positive electrolyte supply branch, and a second control valve for controlling the on-off of the pipeline is provided on the negative electrolyte supply branch; Each of the SOC sub-detection devices is configured to detect the SOC value of one of the battery modules. When the SOC sub-detection device detects that the SOC value of the corresponding battery module reaches a preset value, the first control valve and the second control valve corresponding to the battery module are closed.

2. The liquid flow battery system according to claim 1, characterized in that: A third control valve is provided on the positive electrode electrolyte reflux branch, and a fourth control valve is provided on the negative electrode electrolyte reflux branch; When the SOC sub-detection device detects that the SOC value of the corresponding battery module reaches a preset value, the third control valve and the fourth control valve corresponding to the battery module are disconnected.

3. The liquid flow battery system according to claim 1, characterized in that: The positive electrolyte supply branch is connected with a positive electrolyte bypass flow path between the position upstream of the first control valve and the positive electrolyte tank, and a fifth control valve for controlling the on-off of the pipeline is arranged on the positive electrolyte bypass flow path; The negative electrolyte supply branch is connected with a negative electrolyte bypass flow path between the position upstream of the second control valve and the negative electrolyte tank, and a sixth control valve for controlling the on-off of the pipeline is arranged on the negative electrolyte bypass flow path; When the SOC sub-detection device detects that the SOC value of the corresponding battery module reaches a preset value, the fifth control valve and the sixth control valve corresponding to the battery module are opened.

4. The liquid flow battery system according to claim 1, characterized in that: Each of the SOC sub-detection devices has a positive electrode electrolyte inlet, a negative electrode electrolyte inlet, a positive electrode electrolyte outlet and a negative electrode electrolyte outlet; A first detection flow path is connected between the positive electrode electrolyte inlet and the corresponding positive electrode electrolyte supply branch, a second detection flow path is connected between the negative electrode electrolyte inlet and the corresponding negative electrode electrolyte supply branch, a third detection flow path is connected between the positive electrode electrolyte outlet and the positive electrode electrolyte tank, and a fourth detection electrolyte flow path is connected between the negative electrode electrolyte outlet and the negative electrode electrolyte tank; A seventh control valve is arranged on the first detection flow path, and an eighth control valve is arranged on the second detection flow path; when the SOC sub-detection device detects that the SOC value of the corresponding battery module reaches a preset value, the seventh control valve and the eighth control valve corresponding to the battery module are disconnected.

5. The liquid flow battery system according to claim 1, characterized in that: It also includes an SOC total detection device, which is configured to detect the SOC value of the liquid flow battery system.

6. The liquid flow battery system according to claim 5, characterized in that: The positive electrode electrolyte tank is connected to a positive electrode electrolyte supply main flow path, and the negative electrode electrolyte tank is connected to a negative electrode electrolyte supply main flow path; a plurality of positive electrode electrolyte supply branches are connected to the positive electrode electrolyte supply main flow path, and a plurality of negative electrode electrolyte supply branches are connected to the negative electrode electrolyte supply main flow path; The SOC total detection device has a positive electrode electrolyte total inlet, a positive electrode electrolyte total outlet, a negative electrode electrolyte total inlet and a negative electrode electrolyte total outlet. The positive electrode electrolyte total inlet is connected to the positive electrode electrolyte supply total flow path, the negative electrode electrolyte total inlet is connected to the negative electrode electrolyte supply total flow path, a positive electrode electrolyte circuit is connected between the positive electrode electrolyte total outlet and the positive electrode electrolyte tank, and a negative electrode electrolyte circuit is connected between the negative electrode electrolyte outlet and the negative electrode electrolyte tank.

7. The liquid flow battery system according to claim 6, characterized in that: The main flow path for supplying positive electrolyte is provided with a water pump and a control valve for controlling the on-off of the pipeline; and the main flow path for supplying negative electrolyte is provided with a water pump and a control valve for controlling the on-off of the pipeline.

8. The liquid flow battery system according to claim 7, characterized in that: A positive electrode connection flow path is connected to the positive electrode electrolyte supply main flow path and between the water pump and the SOC main detection device, and the plurality of positive electrode electrolyte supply branches are all connected to the positive electrode connection flow path; A negative electrode connection flow path is connected to the negative electrode electrolyte supply main flow path and between the water pump and the SOC main detection device, and the plurality of negative electrode electrolyte supply branches are all connected to the negative electrode connection flow path.

9. The liquid flow battery system according to any one of claims 1 to 7, characterized in that: There are two preset values, one of which is a first preset value indicating that the battery module is fully charged, and the other preset value is a second preset value indicating that the battery module is fully discharged.

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