Rebalance process system for automatically recovering capacity of flow battery on line

Abstract

The invention discloses a rebalancing process system for automatically recovering the capacity of a flow battery on line. The rebalancing process system comprises a rebalancing solution storage tank, a rebalancing electric pile, a rebalancing electric pile positive electrode circulating pump and a rebalancing electric pile negative electrode circulating pump, a first outlet of the rebalancing galvanic pile is connected with a rebalancing solution storage tank; a liquid outlet of the rebalance solution storage tank is connected with one end of the rebalance galvanic pile positive electrode circulating pump; the other end of the rebalancing galvanic pile positive electrode circulating pump is connected with a first inlet of the rebalancing galvanic pile through a first liquid phase pipeline; and one end of the rebalancing galvanic pile cathode circulating pump is connected with the second inlet of the rebalancing galvanic pile. The rebalance process system for automatically recovering the capacity of the flow battery on line is suitable for engineering application, after the system is started, only rebalance chemicals need to be supplemented into the chemical adding and dissolving tank in a fixed period, the operation process is simple, and long-period operation of the flow battery and efficient utilization of electrolyte can be achieved.

Description

Technical Field

[0001] The present invention belongs to the technical field of liquid flow batteries, and in particular relates to a rebalancing process system for automatically restoring the capacity of a liquid flow battery online. Background Art

[0002] Liquid flow battery is a new type of large-scale electrochemical energy storage device. It stores electrical energy in electrolyte solution during charging and converts the stored energy into electrical energy during discharge. The output power of the battery depends on the size and number of battery stacks, and the storage capacity depends on the concentration and volume of the electrolyte. During the battery charging and discharging process, only the ion valence state in the positive and negative electrolytes changes. The electrolyte can be recycled and reused, and the operation is safe.

[0003] According to the classification of different active materials, the existing flow batteries mainly include all-vanadium flow batteries, iron-chromium flow batteries, zinc-bromine flow batteries, etc. The potential of the redox pairs of the negative electrodes of these flow batteries (including V(II) / V(III), Cr(II) / Cr(III), Zn / Zn(II) pairs, etc.) is generally less than 0V vs. SHE (standard hydrogen electrode). When charging, hydrogen is released at the negative electrode. During the long-term operation of the battery, the state of charge of the positive electrode electrolyte will gradually increase, resulting in a mismatch between the state of charge of the positive electrode electrolyte and the negative electrode electrolyte, causing the battery capacity to decay; at the same time, the hydrogen released from the negative electrode causes the loss of hydrogen ions in the system.

[0004] Therefore, one of the key research and development technologies of iron-chromium flow battery is to restore the active ion concentration of positive and negative electrolytes to the initial state through some methods so that the battery system capacity can be restored. 3+ -H2 rebalances the battery to achieve capacity recovery, but its hydrogen electrode requires the use of Pt or W catalysts, and Pt will penetrate into the negative electrode electrolyte through the ion membrane, thereby contaminating the negative electrode electrolyte. In addition, Pt is relatively expensive and not suitable for industrial applications; W catalysts have poor stability and will deactivate after a period of use. The Chinese patent (publication number CN105702997A) uses a method of reducing Fe by electrolytic reduction through a rebalanced battery. 3+ The positive electrode solution of the rebalanced battery is a positive electrode electrolyte containing active cations, and the negative electrode solution is a positive electrode storage tank of the main system flow battery. However, the cost of the rebalanced solution in this method is high, and each rebalancing requires draining the waste liquid, filling with new liquid, and treating the waste liquid. The labor cost and waste liquid treatment cost are also high.

[0005] Therefore, researching and designing a system and method for realizing capacity recovery in an efficient, convenient and easy-to-operate manner is one of the focuses of researchers in this field. Summary of the invention

[0006] In view of the above problems, the present invention discloses a rebalancing process system for automatically restoring the capacity of a flow battery online, comprising: a rebalancing solution storage tank, a rebalancing stack, a rebalancing stack positive electrode circulation pump, and a rebalancing stack negative electrode circulation pump;

[0007] The first outlet of the rebalancing stack is connected to the rebalancing solution storage tank;

[0008] The liquid outlet of the rebalancing solution storage tank is connected to one end of the positive electrode circulation pump of the rebalancing stack;

[0009] The other end of the rebalanced stack positive electrode circulation pump is connected to the first inlet of the rebalanced stack through a first liquid phase pipeline;

[0010] One end of the rebalanced stack negative electrode circulation pump is connected to the second inlet of the rebalanced stack.

[0011] Furthermore, it also includes: an alkali absorption storage tank;

[0012] The alkali absorption storage tank is connected to the top of the rebalance solution storage tank through a first gas phase pipeline;

[0013] An exhaust pipeline is arranged on the top of the alkali absorption storage tank.

[0014] Furthermore, it also includes: a dosing and dissolution box;

[0015] The top of the drug-adding and dissolving tank is connected to the first liquid phase pipeline through the second liquid phase pipeline;

[0016] The top of the drug-adding and dissolving tank is connected to the first gas phase pipeline through the second gas phase pipeline;

[0017] The bottom end of the dosing and dissolving box is connected to the bottom end of the rebalance solution storage tank.

[0018] Furthermore, it also includes: a flow control device;

[0019] One end of the flow control device is connected to the dosing and dissolution box, and the other end is connected to the rebalancing solution storage tank.

[0020] Furthermore, it also includes: a dosing and dissolving box and a gas cylinder;

[0021] The top of the drug-adding and dissolving tank is connected to the first liquid phase pipeline through the second liquid phase pipeline;

[0022] The top of the drug-adding and dissolving tank is connected to the first gas phase pipeline through the second gas phase pipeline;

[0023] The bottom end of the dosing and dissolution box is connected to the bottom end of the rebalance solution storage tank;

[0024] The gas cylinder is connected with the drug adding and dissolving box.

[0025] Furthermore, it also includes: a flow control device;

[0026] One end of the flow control device is connected to the dosing and dissolution tank, and the other end is connected to the rebalancing solution storage tank;

[0027] Another flow control device has one end connected to the gas cylinder and the other end connected to the dosing and dissolution box.

[0028] Furthermore, it also includes: a gas cylinder;

[0029] The gas cylinder is connected to the rebalance solution storage tank through a gas phase pipeline.

[0030] Furthermore, it also includes: a flow control device;

[0031] One end of the flow control device is connected to the gas cylinder, and the other end is connected to the rebalancing solution storage tank.

[0032] Furthermore, the rebalancing chemical used in the rebalancing process system for automatically restoring the capacity of the flow battery online is a reducing compound;

[0033] The compound contains one or more of hydrogen, carbon, nitrogen, oxygen and chlorine.

[0034] Furthermore, the chemical formula of the compound is H a C b O c N d Cl e ;

[0035] The compound is a solid, liquid or gas;

[0036] Among them, the value range of a~e is 0~4.

[0037] Compared with the prior art, the embodiments of the present invention have at least the following advantages:

[0038] The rebalancing process system for automatically restoring the capacity of a liquid flow battery online of the present invention is suitable for engineering applications. After the system is started, it is only necessary to add rebalancing chemicals to the chemical dissolution tank at a fixed period. The operation process is simple and can achieve long-term operation of the liquid flow battery and efficient use of the electrolyte.

[0039] Other features and advantages of the present invention will be described in the following description, and partly become apparent from the description, or be understood by implementing the present invention. The purpose and other advantages of the present invention can be realized and obtained by the structures pointed out in the description and the drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0040] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the following briefly introduces the drawings required for use in the embodiments or the description of the prior art. Obviously, the drawings described below are some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0041] Figure 1 A schematic diagram of a rebalancing process system for automatically recovering the capacity of a flow battery online according to Example 1 of the present invention is shown;

[0042] Figure 2 A schematic diagram of a rebalancing process system for automatically recovering the capacity of a flow battery online according to Example 2 of the present invention is shown;

[0043] Figure 3 A schematic diagram of a rebalancing process system for automatically restoring the capacity of a flow battery online according to Example 3 of the present invention is shown.

[0044] Figure numerals: 1. Dosing dissolution box; 2. Rebalancing solution storage tank; 3. Rebalancing stack; 4. Alkali absorption tank; 5. Rebalancing stack positive electrode circulation pump; 6. Rebalancing stack negative electrode circulation pump; 7. Flow control device; 8. Gas cylinder. DETAILED DESCRIPTION

[0045] In order to make the purpose, technical solution and advantages of the embodiments of the present invention clearer, the technical solution in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0046] The object of the present invention is to provide a rebalancing process system suitable for engineering applications and capable of automatically restoring the capacity of a flow battery online, and its application.

[0047] This rebalancing process system is composed of a liquid flow battery (main system) positive / negative electrolyte storage tank, a rebalancing solution storage tank 2, a dosing dissolution box 1 and / or a gas cylinder 8, an alkali absorption storage tank 4, a rebalancing stack 3, a rebalancing stack positive electrode circulation pump 5, a rebalancing stack negative electrode circulation pump 6, a flow control device 7, measuring instruments, valves, pipes and pipe fittings. Among them, the liquid flow battery (main system) positive / negative electrolyte storage tank, the rebalancing solution storage tank 2 and the rebalancing stack 3 constitute a set of liquid flow battery system, the rebalancing solution storage tank 2 is the rebalancing stack positive / negative electrolyte storage tank, and the liquid flow battery (main system) positive / negative electrolyte storage tank is the rebalancing stack negative electrolyte storage tank.

[0048] The capacity recovery process is as follows:

[0049] (1) Add a certain amount of rebalancing chemicals to the rebalancing process system to make it react chemically with the high-valent ions in the positive / negative electrolyte storage tanks of the flow battery (main system), such as Fe in the iron-chromium flow battery. 3+ / Cr 3+ , V in all-vanadium liquid flow batteries 3+ / V 5+ , or use the battery stack to cause electrochemical reactions to achieve battery capacity recovery. The rebalancing drug is a compound containing one or more elements of hydrogen, carbon, nitrogen, oxygen, and chlorine that can be reduced (i.e., the element valence state can be increased and has reducing properties) (chemical formula: H a C b O c N d Cl e , wherein a-e is 0-4), the compound can be solid, liquid or gas. The rebalancing drug can also be a mixture of the above substances.

[0050] If the rebalancing chemical is a liquid, it can be directly added to the chemical dissolution tank 1; if the compound is a gas or solid, it needs to be mixed with another liquid substance to form a solution, and then added to the chemical dissolution tank 1. The mixing process can also be carried out in the chemical dissolution tank 1. The above-mentioned liquid substance can be a rebalancing chemical that is liquid itself, or it can be water. In addition, acid can be further added to the chemical dissolution tank 1, and when it is used as a rebalancing system for an iron-chromium liquid flow battery, a compound or mixture containing iron ions and chromium ions can also be added, and when it is used as a rebalancing system for an all-vanadium liquid flow battery, a compound or mixture containing vanadium ions can also be added.

[0051] The reducing compounds lose electrons during the reaction, which enables the cations in the flow battery to gain electrons and change from a high-valent state to a low-valent state, thereby restoring the capacity of the flow battery and replenishing the hydrogen ions lost in the main system.

[0052] (2) The dosing dissolution tank 1 is connected to the rebalancing solution storage tank 2 through a pipeline via a flow control device 7. The rebalancing solution in the dosing dissolution tank 1 automatically flows continuously or intermittently into the rebalancing solution storage tank 2 through the pipeline according to the flow rate set by the flow control device 7.

[0053] (3) When the rebalancing chemical is only gas, the rebalancing process system may also not use the chemical dissolution tank 1, and directly use a pressure gas cylinder or a liquefied gas tank, which is connected to the rebalancing solution storage tank 2 through a pipeline via a flow control device 7. The gas in the gas cylinder 8 automatically flows into the rebalancing solution storage tank 2 through the pipeline continuously or intermittently according to the flow rate set by the flow control device 7.

[0054] (4) The liquid flow battery system composed of the rebalancing solution storage tank 2, the positive / negative electrolyte storage tank of the liquid flow battery (main system), and the rebalancing stack 3 can be automatically charged continuously or intermittently according to the demand settings to reduce the high-valent ions in the positive / negative electrolyte of the liquid flow battery (main system) to chemical reactions, such as Fe in the iron-chromium liquid flow battery. 3+ / Cr 3+ , V in all-vanadium liquid flow batteries 3+ / V 5+ , thereby realizing the recovery of the electrolyte capacity of the main system of the flow battery, extending the battery life and ensuring the battery performance.

[0055] (5) When the rebalancing stack 3 produces tail gas such as chlorine that needs to be absorbed, it can be absorbed by the alkaline absorption tank 4; when the rebalancing stack 3 produces tail gas such as oxygen, nitrogen, carbon dioxide that does not need to be absorbed, it can be directly discharged.

[0056] Example 1

[0057] Figure 1 The schematic diagram of the rebalancing process system for automatically recovering the capacity of a flow battery online according to Example 1 of the present invention is shown (the solid line in the figure is the liquid phase pipeline, and the dotted line is the gas phase pipeline). Figure 1 As shown, the present invention proposes a rebalancing process system for automatically restoring the capacity of a flow battery online, comprising: a rebalancing solution storage tank 2, a rebalancing stack 3, a rebalancing stack positive electrode circulation pump 5 and a rebalancing stack negative electrode circulation pump 6;

[0058] The first outlet of the rebalancing stack 3 is connected to the rebalancing solution storage tank 2 through a liquid phase pipeline, and one end of the liquid phase pipeline is located above the liquid level of the rebalancing solution storage tank 2;

[0059] The liquid outlet of the rebalancing solution storage tank 2 is connected to one end of the rebalancing stack positive electrode circulation pump 5 through a liquid phase pipeline;

[0060] The other end of the rebalancing stack positive electrode circulation pump 5 is connected to the first inlet of the rebalancing stack 3 through a first liquid phase pipeline;

[0061] One end of the rebalancing stack negative electrode circulation pump 6 is connected to the second inlet of the rebalancing stack 3, and the other end is connected to the liquid outlet of the positive / negative electrolyte storage tank of the flow battery (main system);

[0062] The second outlet of the rebalancing stack 3 is connected to the liquid return port of the positive / negative electrolyte storage tank of the liquid flow battery (main system).

[0063] A rebalancing solution storage tank 2, used for storing a rebalancing solution for a rebalancing stack 3 reaction;

[0064] The rebalancing stack 3 is used to provide a reaction site and conditions for the rebalancing solution and the positive / negative electrolyte of the flow battery (main system);

[0065] A rebalancing stack positive electrode circulation pump 5 is used to supply the solution of the rebalancing solution storage tank 2 required in the rebalancing stack 3;

[0066] The rebalancing stack negative electrode circulation pump 6 is used to supply the solution of the positive electrode / negative electrode electrolyte storage tank of the liquid flow battery (main system) required in the rebalancing stack 3.

[0067] The rebalancing process system for automatically restoring the capacity of the flow battery online in this embodiment requires a dosing dissolution tank 1, but does not require a gas cylinder 8, that is, the rebalancing drug is a liquid or a solid that needs to be dissolved. The rebalancing solution storage tank 2, the positive / negative electrolyte storage tank of the flow battery (main system), and the rebalancing stack 3 form a flow battery system that can be automatically charged continuously or intermittently according to the demand setting to restore the Fe in the positive / negative electrolyte of the flow battery (main system). 3+ / Cr 3+ , thereby realizing the recovery of the electrolyte capacity of the main system, extending the battery life and ensuring the battery performance.

[0068] In some embodiments, a rebalancing process system for automatically restoring the capacity of a flow battery online further includes: an alkali absorption storage tank 4;

[0069] The alkali absorption storage tank 4 is connected to the top of the rebalance solution storage tank 2 through a first gas phase pipeline, and one end of the first gas phase pipeline extends below the liquid level of the alkali absorption storage tank 4;

[0070] The top of the alkali absorption tank 4 is provided with an exhaust pipeline.

[0071] The alkali absorption tank 4 is used to absorb the tail gas such as chlorine generated by the rebalancing stack 3 to prevent air pollution.

[0072] In some embodiments, a rebalancing process system for automatically restoring the capacity of a flow battery online further includes: a dosing dissolution tank 1;

[0073] The top of the dosing and dissolving tank 1 is connected to the first liquid phase pipeline through a second liquid phase pipeline, and one end of the second liquid phase pipeline is located above the liquid level of the dosing and dissolving tank 1;

[0074] The top of the dosing and dissolving tank 1 is connected to the first gas phase pipeline through the second gas phase pipeline;

[0075] The bottom end of the dosing and dissolving box 1 is connected to the bottom end of the rebalancing solution storage tank 2 .

[0076] The dosing dissolution box 1 is used to supply the required rebalancing solution in the rebalancing solution storage tank 2 in a timely and quantitative manner; it reduces manual operations and can complete the dissolution during the idle period of the system.

[0077] In some embodiments, a rebalancing process system for automatically restoring the capacity of a flow battery online further includes: a flow control device 7;

[0078] One end of the flow control device 7 is connected to the dosing and dissolution tank 1 , and the other end is connected to the rebalancing solution storage tank 2 .

[0079] Exemplarily, the flow control device 7 may be a metering pump, or a combination of a centrifugal pump and a flow meter.

[0080] The flow control device 7 is used to set the flow rate to automatically and continuously or intermittently transport the rebalancing solution in the dosing and dissolution box 1 to the rebalancing solution storage tank 2, and can timely restore the high-valent ions in the positive / negative electrolyte of the main system according to the setting, thereby realizing rapid recovery of the electrolyte capacity of the main system.

[0081] The rebalancing process system provided by the present invention is suitable for engineering applications and can automatically restore the capacity of a flow battery online. After the system is started, it is only necessary to add rebalancing chemicals to the chemical dissolution tank 1 at a fixed period. The operation process is simple and can achieve long-term operation of the battery and efficient use of the electrolyte.

[0082] Example 2

[0083] Figure 2 FIG. 2 shows a schematic diagram of a rebalancing process system for automatically recovering the capacity of a flow battery online according to Example 2 of the present invention. Figure 2 As shown, the present invention also discloses a rebalancing process system for automatically restoring the capacity of a liquid flow battery online, which is similar to Example 1, except that the system of this embodiment requires a chemical dissolution box 1 and a gas cylinder 8, and the added rebalancing chemical is a gas that needs to be dissolved.

[0084] In some embodiments, a rebalancing process system for automatically restoring the capacity of a flow battery online further includes: a dosing dissolution tank 1 and a gas cylinder 8;

[0085] The top of the dosing and dissolving tank 1 is connected to the first liquid phase pipeline through a second liquid phase pipeline, and one end of the second liquid phase pipeline is located above the liquid level of the dosing and dissolving tank 1;

[0086] The top of the dosing and dissolving tank 1 is connected to the first gas phase pipeline through the second gas phase pipeline;

[0087] The bottom end of the dosing and dissolution tank 1 is connected to the bottom end of the rebalancing solution storage tank 2;

[0088] The gas cylinder 8 is connected to the dosing and dissolving tank 1 through a gas phase pipeline, and the gas phase pipeline extends below the liquid level of the dosing and dissolving tank 1.

[0089] The gas cylinder 8 is used to store gaseous rebalance drugs.

[0090] In some embodiments, a rebalancing process system for automatically restoring the capacity of a flow battery online further includes: a flow control device 7;

[0091] One end of the flow control device 7 is connected to the dosing and dissolution tank 1, and the other end is connected to the rebalancing solution storage tank 2;

[0092] Another flow control device 7 has one end connected to the gas cylinder 8 and the other end connected to the dosing and dissolution box 1 .

[0093] The gas cylinder 8 is connected to the re-dosing dissolution tank 1 through a pipeline via a flow control device 7. The gas in the gas cylinder 8 automatically, continuously or intermittently flows through the pipeline into the dosing dissolution tank 1 according to the flow rate set by the flow control device 7, and is dissolved in the dosing dissolution tank 1. After dissolution, the gas automatically, continuously or intermittently flows through the pipeline into the re-balancing solution storage tank 2 according to the set flow rate through the flow control device 7.

[0094] Example 3

[0095] Figure 3 FIG. 2 shows a schematic diagram of a rebalancing process system for automatically recovering the capacity of a flow battery online according to Example 3 of the present invention. Figure 3 As shown, the present invention also discloses a rebalancing process system for automatically restoring the capacity of a liquid flow battery online, which is similar to Example 1, except that the system of this embodiment requires a gas cylinder 8 but does not require a drug dissolution box 1, that is, the added rebalancing drug is a gas that does not need to be dissolved in advance.

[0096] In some embodiments, a rebalancing process system for automatically restoring the capacity of a flow battery online further includes: a gas cylinder 8;

[0097] The gas cylinder 8 is connected to the rebalancing solution storage tank 2 via a gas phase pipeline, and one end of the gas phase pipeline extends below the liquid level of the rebalancing solution storage tank 2 .

[0098] In some embodiments, a rebalancing process system for automatically restoring the capacity of a flow battery online further includes: a flow control device 7;

[0099] One end of the flow control device 7 is connected to the gas cylinder 8 , and the other end is connected to the rebalancing solution storage tank 2 .

[0100] The gas cylinder 8 is connected to the rebalancing solution storage tank 2 through a pipeline via a flow control device 7. The gas (rebalancing drug) in the gas cylinder 8 automatically, continuously or intermittently flows through the pipeline into the rebalancing solution storage tank 2 according to the flow rate set by the flow control device 7, and the gas quickly dissolves in the rebalancing solution storage tank 2.

[0101] The present invention uses different rebalancing chemicals to verify the rebalancing process system for automatically recovering the capacity of the flow battery online in the above embodiment, and the capacity recovery rate is as follows:

[0102] Verification Example 1

[0103] When a=4, b=0, c=0, d=1, e=1, that is, the drug is ammonium chloride (NH4Cl), a certain amount of ammonium chloride solid is added to the dosing and dissolving tank 1 containing the acidic solution of iron ions and chromium ions. The system flow chart is as above. Figure 1 As shown, the capacity is restored according to the implementation steps, and the overall reaction is:

[0104] 2NH4Cl+8Fe 3+ =N2+Cl2+8Fe 2+ +8H +

[0105] The specific test results are shown in Table 1.

[0106] Table 1 Capacity recovery data after adding ammonium chloride

[0107] Capacity recovery rate / % Before rebalancing 100 Rebalance - 1 95.30 Rebalance - 2 96.84 Rebalance - 3 95.28

[0108] Verification Example 2

[0109] When a=2, b=1, c=1, d=0, e=0, that is, the drug is formaldehyde (HCHO), formaldehyde is directly introduced into the dosing and dissolving tank 1 filled with water as a rebalancing drug to form a formaldehyde aqueous solution. The system flow chart is as shown above. Figure 2 or Figure 3 As shown, the capacity is restored according to the implementation steps, and the overall reaction is:

[0110] HCHO+4Fe 3+ +H2O=CO2+4Fe 2+ +4H +

[0111] The specific test results are shown in Table 2.

[0112] Table 2 Capacity recovery data after adding formaldehyde

[0113] Capacity recovery rate / % Before rebalancing 100 Rebalance - 1 93.10 Rebalance - 2 97.63 Rebalance - 3 94.39

[0114] Verification Example 3

[0115] When a=4, b=1, c=1, d=0, e=0, that is, the drug is methanol (CH3OH), a methanol solution of a certain concentration is directly introduced into the rebalancing solution storage tank 2 as the rebalancing drug. The system flow chart is as shown in the above attached Figure 1 As shown, the capacity is restored according to the implementation steps, and the overall reaction is:

[0116] CH3OH+6Fe 3+ +H2O=CO2+6Fe 2+ +6H +

[0117] The specific test results are shown in Table 3.

[0118] Table 3 Capacity recovery data after adding methanol

[0119] Capacity recovery rate / % Before rebalancing 100 Rebalance - 1 98.50 Rebalance - 2 97.63 Rebalance - 3 98.39

[0120] The present invention is applicable to commercial liquid flow battery systems and has a prospect for large-scale promotion and application in the fields of electrochemical energy storage technology research, engineering application of energy storage technology, etc.

[0121] Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or make equivalent substitutions for some of the technical features therein; and these modifications or substitutions do not make the essence of the corresponding technical solutions deviate from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A rebalancing process system for automatically restoring the capacity of a flow battery online, characterized in that: include: A rebalancing solution storage tank (2), a rebalancing stack (3), a rebalancing stack positive electrode circulation pump (5) and a rebalancing stack negative electrode circulation pump (6); The first outlet of the rebalancing stack (3) is connected to the rebalancing solution storage tank (2); The liquid outlet of the rebalancing solution storage tank (2) is connected to one end of the rebalancing stack positive electrode circulation pump (5); The other end of the rebalanced stack positive electrode circulation pump (5) is connected to the first inlet of the rebalanced stack (3) via a first liquid phase pipeline; One end of the rebalanced stack negative electrode circulation pump (6) is connected to the second inlet of the rebalanced stack (3).

2. The rebalancing process system for automatically restoring the capacity of a flow battery online according to claim 1, characterized in that: Also includes: Alkali absorption storage tank (4); The alkali absorption storage tank (4) is connected to the top of the rebalance solution storage tank (2) via a first gas phase pipeline; An exhaust pipeline is arranged at the top of the alkali absorption storage tank (4).

3. The rebalancing process system for automatically restoring the capacity of a flow battery online according to claim 2, characterized in that: Also includes: Dosing and dissolving box (1); The top of the drug-adding and dissolving box (1) is connected to the first liquid phase pipeline via a second liquid phase pipeline; The top of the drug-adding and dissolving box (1) is connected to the first gas phase pipeline via a second gas phase pipeline; The bottom end of the drug addition and dissolution box (1) is connected to the bottom end of the rebalancing solution storage tank (2).

4. The rebalancing process system for automatically restoring the capacity of a flow battery online according to claim 3, characterized in that: Also includes: Flow control device (7); One end of the flow control device (7) is connected to the dosing and dissolution tank (1), and the other end is connected to the rebalancing solution storage tank (2).

5. The rebalancing process system for automatically restoring the capacity of a flow battery online according to claim 2, characterized in that: Also includes: A dosing and dissolving box (1) and a gas cylinder (8); The top of the drug-adding and dissolving box (1) is connected to the first liquid phase pipeline via a second liquid phase pipeline; The top of the drug-adding and dissolving box (1) is connected to the first gas phase pipeline via a second gas phase pipeline; The bottom end of the drug addition and dissolution box (1) is connected to the bottom end of the rebalancing solution storage tank (2); The gas cylinder (8) is connected to the drug-adding and dissolving box (1).

6. The rebalancing process system for automatically restoring the capacity of a flow battery online according to claim 5, characterized in that: Also includes: Flow control device (7); One end of the flow control device (7) is connected to the dosing and dissolution tank (1), and the other end is connected to the rebalancing solution storage tank (2); Another flow control device (7) has one end connected to the gas cylinder (8) and the other end connected to the dosing and dissolution box (1).

7. The rebalancing process system for automatically restoring the capacity of a flow battery online according to claim 2, characterized in that: Also includes: Gas cylinders (8); The gas cylinder (8) is connected to the rebalance solution storage tank (2) via a gas phase pipeline.

8. The rebalancing process system for automatically restoring the capacity of a flow battery online according to claim 7, characterized in that: Also includes: Flow control device (7); One end of the flow control device (7) is connected to the gas cylinder (8), and the other end is connected to the rebalancing solution storage tank (2).

9. The rebalancing process system for automatically restoring the capacity of a flow battery online according to any one of claims 4, 6 or 8, characterized in that: The rebalancing chemical used in the rebalancing process system for automatically restoring the capacity of a flow battery online is a reducing compound; The compound contains one or more of hydrogen, carbon, nitrogen, oxygen and chlorine.

10. The rebalancing process system for automatically restoring the capacity of a flow battery online according to claim 9, characterized in that: The chemical formula of the compound is H a C b O c N d Cl e ; The compound is a solid, liquid or gas; Among them, the value range of a~e is 0~4.

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