Electrolyte storage tank and flow battery energy storage system

Abstract

The invention relates to an electrolyte storage tank and a flow battery energy storage system. The electrolyte storage tank comprises a tank body, a heat exchange pipeline, a liquid outlet and a liquid inlet, wherein the liquid outlet and the liquid inlet are formed in the tank body. The tank body comprises an inner container and an outer jacket arranged outside the inner container in a wrapping mode, and the inner container is used for storing electrolyte. The inner container is made of a metal material, the inner wall of the inner container is coated with a coating, the outer jacket is made of a non-metal material, and a gap is formed between the outer jacket and the inner container to form a mounting space. And the heat exchange pipeline is arranged in a mounting space between the outer jacket and the inner container and is used for circulating a heat exchange medium. The liquid outlet is formed in the bottom of the tank body. The liquid inlet is formed in the top of the tank body. The inner container is made of metal, so that the structural strength of the storage tank is improved, and the service life of the storage tank is prolonged. And as the inner container is completely arranged in the outer jacket, the electrolyte can be effectively prevented from leaking outwards. And by arranging the heat exchange pipeline, the electrolyte in the inner container can be subjected to heat exchange, the heat exchange effect is good, and the storage tank can be kept at a proper temperature.

Description

Technical Field

[0001] The present invention relates to the technical field of liquid flow batteries, and in particular to an electrolyte storage tank and a liquid flow battery energy storage system. Background Art

[0002] In a flow battery system, the storage tank is the main storage device for electrolyte. Existing electrolyte storage tanks are generally plastic storage tanks, which have insufficient structural strength and are prone to deformation, causing safety issues such as electrolyte leakage.

[0003] Moreover, when the temperature is high in summer, the long-term operation of the electrolyte can easily cause the electrolyte inside the tank to heat up. In traditional technology, heat is generally dissipated by adding a heat exchanger or extending the coil outside the tank. This method is not ideal in the summer in the south and cannot keep the tank in the appropriate temperature range. Summary of the invention

[0004] One purpose of the present invention is to solve the deficiencies in the prior art and provide an electrolyte storage tank. To solve the above technical problems, the present invention adopts the following technical solutions:

[0005] An electrolyte storage tank, comprising:

[0006] The tank body includes an inner container and an outer jacket wrapped around the inner container, the inner container is used to store electrolyte, the inner container is made of metal, the inner wall of the inner container is coated with a coating, the outer jacket is made of non-metallic material, and there is a gap between the outer jacket and the inner container to form an installation space;

[0007] A heat exchange pipeline is arranged in the installation space between the outer jacket and the inner container, and is used for circulating a heat exchange medium;

[0008] A liquid outlet, which is arranged at the bottom of the tank body, the liquid outlet is used to connect the liquid outlet pipe and the interior of the inner container, and the liquid outlet pipe is used to output the electrolyte in the inner container;

[0009] The liquid inlet is arranged on the top of the tank body, and is used to connect the liquid return pipe and the interior of the inner container, and the liquid return pipe is used to allow the electrolyte to flow back into the inner container.

[0010] In one embodiment, the electrolyte storage tank further includes a liquid mixing port, which is disposed on the side wall of the tank body and is used to connect to a liquid mixing tube, which is used to connect to an inner container storing electrolytes of different polarities.

[0011] In one embodiment, the electrolyte storage tank further includes a liquid level balance port, which is disposed on the side wall of the tank body, and is used to connect to a liquid level balance pipe, which is used to connect to an inner container storing electrolyte of the same polarity.

[0012] In one embodiment, the electrolyte storage tank further includes a liquid level meter, which is disposed on the tank body and is used to detect the liquid level in the inner container.

[0013] In one embodiment, the electrolyte storage tank further comprises:

[0014] A main pipe, which is arranged in the inner container and close to the bottom of the inner container, and the outlet end of the main pipe penetrates the side wall of the tank body and forms a liquid outlet;

[0015] Multiple branch pipelines are evenly arranged at the bottom of the inner container. The multiple branch pipelines are all open at one end. The open end of each branch pipeline is connected to the main pipeline. Multiple liquid inlet holes are opened on each branch pipeline.

[0016] In one of the embodiments, the electrolyte storage tank further includes a liquid leakage sensor, which is disposed at the bottom of the tank body and is located in the installation space between the outer jacket and the inner container.

[0017] In one of the embodiments, the electrolyte storage tank further includes a safety valve port, which is disposed at the top of the tank body and is used to connect the safety valve and / or waste gas collection pipeline.

[0018] In one embodiment, the electrolyte storage tank further includes a nitrogen filling port, which is arranged on the top of the tank body and is used to connect to a nitrogen filling pipeline;

[0019] A liquid infusion port, which is arranged on the top of the tank body and is used to connect to a liquid infusion pipeline;

[0020] Manhole: The manhole is arranged on the top of the tank body.

[0021] In one of the embodiments, the electrolyte storage tank further comprises a frame, and the frame is connected to the outside of the outer jacket.

[0022] Another object of the present invention is to provide a liquid flow battery energy storage system, comprising a battery stack unit and at least two electrolyte storage tanks, wherein the electrolyte storage tank is the electrolyte storage tank described in any one of the above items;

[0023] The stack unit is provided with a positive electrode inlet, a positive electrode outlet, a negative electrode inlet and a negative electrode outlet;

[0024] At least two electrolyte storage tanks include a first electrolyte storage tank for storing positive electrode electrolyte and a second electrolyte storage tank for storing negative electrode electrolyte;

[0025] The liquid outlet of the first electrolyte storage tank is connected to the positive electrode inlet, and the liquid inlet of the first electrolyte storage tank is connected to the positive electrode outlet;

[0026] The liquid outlet of the second electrolyte storage tank is communicated with the negative electrode inlet, and the liquid inlet of the second electrolyte storage tank is communicated with the negative electrode outlet.

[0027] In one embodiment, the liquid flow battery energy storage system also includes a mixing pipe and a control valve, one end of the mixing pipe is connected to the first electrolyte storage tank, and the other end is connected to the second electrolyte storage tank. The control valve is arranged on the mixing pipe to control the conduction and cutoff of the mixing pipe.

[0028] In one embodiment, the liquid flow battery energy storage system further includes a liquid level balance pipe, and both ends of the liquid level balance pipe are respectively connected to the two first electrolyte storage tanks; and / or

[0029] Both ends of the liquid level balance pipe are respectively connected to the two second electrolyte storage tanks.

[0030] It can be seen from the above technical solution that the present invention has at least the following advantages and positive effects:

[0031] In the present invention, the electrolyte storage tank includes a tank body, a heat exchange pipeline, and a liquid outlet and a liquid inlet opened on the tank body. Among them, the tank body includes an inner container and an outer jacket wrapped and arranged outside the inner container, the inner container is made of metal and is used to store electrolyte, and the inner wall of the inner container is coated with a coating. The outer jacket is made of non-metallic material and is spaced from the inner container to form an installation space. The use of metal material for the inner container can improve the structural strength of the storage tank and extend the service life of the storage tank. Since the inner container is completely placed inside the outer jacket, the risk of direct collision of the inner container is avoided, making the storage tank safer. Since the outer jacket is wrapped and arranged outside the inner container, it can effectively prevent the electrolyte from leaking out.

[0032] By setting up a heat exchange pipeline, the electrolyte in the inner container can be heat exchanged, and the heat exchange effect is good, so that the temperature of the electrolyte in the inner container can be maintained at a suitable temperature, which is beneficial to improving the battery energy storage efficiency. BRIEF DESCRIPTION OF THE DRAWINGS

[0033] Figure 1 It is a schematic structural diagram of an electrolyte storage tank according to one embodiment of the present invention.

[0034] Figure 2 It is a schematic diagram of the tank structure of an electrolyte storage tank according to one embodiment of the present invention.

[0035] Figure 3 yes Figure 2 Schematic diagram of the structure shown when viewed along the direction of arrow A.

[0036] Figure 4 yes Figure 2 BB cross-sectional schematic diagram of the structure shown.

[0037] Figure 5 yes Figure 4 An enlarged schematic diagram of point C of the structure shown.

[0038] Figure 6It is a schematic diagram of the tank structure of an electrolyte storage tank according to another embodiment of the present invention.

[0039] Figure 7 yes Figure 6 An enlarged schematic diagram of point D of the structure shown.

[0040] Figure 8 yes Figure 6 Schematic diagram of the structure of the bottom of the inner container in the tank body shown.

[0041] Fig. 9 It is a schematic diagram of the tank structure of an electrolyte storage tank according to another embodiment of the present invention.

[0042] Fig.10 yes Fig. 9 Schematic diagram of the structure of the bottom of the inner container in the tank body shown.

[0043] Fig.11 Schematic diagram of the principle of a temperature control unit according to one embodiment of the present invention.

[0044] Fig.12 Schematic diagram of a liquid flow battery energy storage system according to one embodiment of the present invention.

[0045] Fig.13 It is a schematic diagram of a liquid flow battery energy storage system according to another embodiment of the present invention.

[0046] The following are the descriptions of the reference numerals:

[0047] 10-electrolyte storage tank; 11-first electrolyte storage tank; 12-second electrolyte storage tank; 13-safety valve; 14-liquid level gauge;

[0048] 20-cell stack unit; 30-liquid outlet pipe; 31-liquid suction pump; 40-liquid return pipe; 50-liquid mixing pipe; 51-control valve; 60-liquid level balance pipe; 70-liquid replenishment pipeline; 80-waste gas collection pipeline; 90-waste gas treatment device;

[0049] 100-tank body; 110-inner container; 111-outer jacket; 112-coating; 113-installation space; 114-heat exchange pipeline; 115-liquid outlet; 116-liquid inlet; 117-liquid mixing port; 118-liquid level balance port; 119-liquid leakage sensor; 120-safety valve port; 121-nitrogen filling port; 122-liquid replenishing port; 123-manhole; 124-main pipeline; 125-branch pipeline; 126-liquid suction hole; 127-temperature sensor;

[0050] 200-frame; 210-end frame; 220-side beam;

[0051] 300-temperature control unit; 310-temperature controller; 320-heat exchange medium container; 330-circulation pump; 340-electric heater; 350-compressor; 360-condenser; 370-expansion valve; 380-evaporator; 390-electromagnetic four-way valve. DETAILED DESCRIPTION

[0052] Typical embodiments that embody the features and advantages of the present invention will be described in detail in the following description. It should be understood that the present invention can have various changes in different embodiments without departing from the scope of the present invention, and the descriptions and illustrations therein are essentially used for illustration purposes rather than for limiting the present invention.

[0053] In the description of the present application, it should be understood that in the embodiments shown in the drawings, the indications of directions or positional relationships (such as up, down, left, right, front and back, etc.) are only for the convenience of describing the present application and simplifying the description, rather than indicating or implying that the devices or elements referred to must have a specific orientation, be constructed and operate in a specific orientation. These descriptions are appropriate when these elements are in the positions shown in the drawings. If the descriptions of the positions of these elements change, the indications of these directions also change accordingly.

[0054] In addition, the terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Thus, the features defined as "first" and "second" may explicitly or implicitly include one or more of the features. In the description of this application, the meaning of "plurality" is two or more, unless otherwise clearly and specifically defined.

[0055] See also Figures 1 to 5 As shown, the electrolyte storage tank 10 according to the embodiment of the present invention includes a tank body 100 , a heat exchange pipeline 114 , and a plurality of functional ports opened on the tank body 100 .

[0056] The tank body 100 is a vertically arranged tank structure. Figure 4 and Figure 5 As shown, the tank 100 includes an inner container 110 and an outer jacket 111. The inner container 110 is used to store electrolyte. For example, the inner container 110 may include a cylinder and two heads arranged at both ends of the cylinder.

[0057] The outer jacket 111 is wrapped around the outer portion of the inner container 110. There is a gap between the outer jacket 111 and the inner container 110 to form an installation space 113. For example, the outer jacket 111 may include a cylinder and two heads disposed at both ends of the cylinder. In addition, the outer jacket 111 and the inner container 110 are preferably coaxially disposed.

[0058] In other embodiments, the tank body 100 may also be in other three-dimensional shapes such as a sphere, a spherical kettle, or a column.

[0059] The inner container 110 may be made of metal, which can improve the structural strength of the storage tank and extend the service life of the storage tank.

[0060] Since the inner container 110 is used to store electrolyte, when the inner container 110 is made of metal material, a coating 112 may be applied to the inner wall of the inner container 110. The coating 112 may be made of a known coating material that is resistant to acid and alkali corrosion, is insulating, and has high thermal conductivity. The thermal conductivity of the coating 112 may be greater than 1 W / (m·k), and the thickness of the coating 112 may be greater than 100 μm.

[0061] Furthermore, the outer jacket 111 may be made of non-metallic materials, for example, the outer jacket 111 may be made of insulating materials such as glass fiber reinforced plastics (GRP), polyethylene (PE), homopolymer polypropylene (PPH), and polytetrafluoroethylene (PTFE).

[0062] In the present application, the inner container 110 is used to store electrolyte, and because the inner container 110 is completely placed inside the outer jacket 111, the risk of direct collision of the inner container 110 is avoided, and safety is higher.

[0063] Since the outer jacket 111 is wrapped and arranged outside the inner container 110, it can effectively prevent the electrolyte from leaking outward. Specifically, there is a gap between the outer jacket 111 and the inner container 110. When the inner container 110 leaks, the electrolyte flows down along the outer wall of the inner container 110, and the leaked liquid exists in the gap between the outer jacket 111 and the inner container 110. That is, the outer jacket 111 can well protect the electrolyte from secondary leakage.

[0064] See also Figure 6 and Figure 7 In one embodiment, the electrolyte storage tank 10 further includes a leakage sensor 119, which is disposed at the bottom of the tank body 100 and is located in the installation space 113 between the outer jacket 111 and the inner container 110. By providing the leakage sensor 119, it is possible to detect in real time whether the inner container 110 is leaking. When electrolyte leakage occurs, the electrolyte flows down along the outer wall of the inner container 110 to the bottom of the tank body 100, so that the leakage sensor 119 can quickly detect the leakage. In addition, the leakage sensor 119 can send an alarm signal to the external control system to remind the operator to handle it in time to ensure the safety of personnel and equipment.

[0065] See also Figure 1 In one embodiment, the electrolyte storage tank 10 further includes a frame 200, and the frame 200 is connected to the outside of the outer jacket 111. For example, the structure of the frame 200 can be: the frame 200 includes two end frames 210, and four side beams 220 connected between the two end frames 210. Among them, the two end frames 210 are respectively arranged at the two ends of the tank body 100. The two end frames 210 and the four side beams 220 can roughly form a box-type frame structure, and the outer jacket 111 is accommodated in the frame structure. Therefore, the frame 200 can effectively protect the outer jacket 111 and the inner container 110, ensuring the safety of the electrolyte storage tank 10.

[0066] In one embodiment, a hoisting hole may be provided on the frame 200. By providing the hoisting hole, the electrolyte storage tank 10 can be hoisted by a special hoisting device, which facilitates the use and transportation of the electrolyte storage tank 10.

[0067] By setting the frame 200, the frame 200 can provide protection for the inner container 110 and the outer jacket 111. Compared with traditional pure non-metallic storage tanks, the electrolyte storage tank 10 of the present application has higher safety and is easy to move and transport.

[0068] like Figure 5 As shown, in the embodiment of the present application, the heat exchange pipeline 114 is arranged in the installation space 113 between the outer jacket 111 and the inner container 110, and the heat exchange pipeline 114 is used to circulate the heat exchange medium. The heat exchange medium can be a liquid with a low boiling point and a high specific heat, such as ethylene glycol, butane, etc. In this embodiment, the electrolyte in the inner container 110 can be heat exchanged through the heat exchange pipeline 114, so that the temperature of the electrolyte in the inner container 110 is maintained at a suitable temperature, which is conducive to improving the battery energy storage efficiency.

[0069] Preferably, the heat exchange pipe 114 may be disposed on the outer wall of the inner container 110. Since the heat exchange pipe 114 is directly disposed on the outer wall of the inner container 110, the heat exchange pipe 114 can directly contact the inner container 110 for heat exchange, so that the heat exchange effect is good, which is conducive to accurately controlling the temperature of the electrolyte in the tank.

[0070] In the present application, the heat exchange pipeline 114 can directly contact the inner container 110, and cooperate with the coating 112 with high thermal conductivity on the inner wall of the inner container 110 to quickly exchange heat for the electrolyte in the inner container 110. The heat exchange effect is good and the heat exchange efficiency is high, which is beneficial to maintain the electrolyte at the optimal operating temperature and thus improve the power storage efficiency.

[0071] The heat exchange pipeline 114 may be arranged in a circuitous manner or a serpentine manner outside the inner container 110, thereby greatly increasing the pipeline length, increasing the heat exchange area, and optimizing the temperature control effect.

[0072] In one embodiment, a temperature sensor 127 may be provided on the outer wall of the inner container 110, and the temperature sensor 127 is used to detect the temperature of the liquid in the inner container 110. The temperature sensor 127 may be connected to the temperature control unit 300. The temperature control unit 300 may control the heat exchange pipeline 114 to exchange heat with the electrolyte in the inner container 110 according to the temperature change of the liquid in the inner container 110 detected by the temperature sensor 127. In this embodiment, the temperature of the electrolyte in the inner container 110 can be accurately controlled by the temperature sensor 127, the temperature control unit 300 and the heat exchange pipeline 114, so that the temperature of the electrolyte in the tank is maintained at an appropriate temperature, so as to improve the battery energy storage efficiency.

[0073] For example, Fig.11 As shown, the temperature control unit 300 may include a temperature controller 310, a heat exchange medium container 320, a circulation pump 330, an electric heater 340, and a compressor 350, a condenser 360, an expansion valve 370 and an evaporator 380 connected in sequence, and an electromagnetic four-way valve 390 arranged between the compressor 350, the condenser 360 and the evaporator 380. Among them, the function of the electromagnetic four-way valve 390 is to control the compressor 350 to connect the condenser 360 or the evaporator 380. The evaporator 380 contacts the heat exchange medium container 320 to perform heat exchange on the heat exchange medium in the heat exchange medium container 320. The temperature controller 310 is electrically connected to the temperature sensor 127. The heat exchange medium container 320 is connected to the heat exchange pipeline 114 through the circulation pump 330. The electric heater 340 can be an electric heating plate, which is used to heat the heat exchange medium in the heat exchange medium container 320.

[0074] When the temperature control unit 300 is working, the temperature value of the temperature controller 310 can be set in advance, and the temperature controller 310 can obtain the temperature value detected by the temperature sensor 127 in real time, and compare the temperature value detected by the temperature sensor 127 with the set temperature value of the temperature controller 310 to determine whether the temperature control unit 300 enters the cooling mode or the heating mode.

[0075] In the cooling mode, the compressor 350 compresses the refrigerant to increase its temperature and pressure. The temperature controller 310 adjusts the electromagnetic four-way valve 390 to connect the compressor 350 with the condenser 360. After the compressor 350 is turned on, the high-temperature and high-pressure refrigerant is sent to the condenser 360, where the refrigerant releases heat and becomes a high-pressure liquid. Next, the high-pressure liquid passes through the expansion valve 370, and the pressure and temperature are reduced. After that, the low-temperature and low-pressure refrigerant enters the evaporator 380, where the low-temperature and low-pressure refrigerant absorbs the heat of the heat exchange medium in the heat exchange medium container 320, so the temperature of the heat exchange medium in the heat exchange medium container 320 decreases, and can be sent to the heat exchange pipeline 114 for circulation through the circulation pump 330. Therefore, the heat exchange pipeline 114 can exchange heat with the electrolyte in the inner container 110, so that the temperature of the electrolyte in the inner container 110 is reduced. The low-temperature and low-pressure refrigerant in the evaporator 380 absorbs heat and evaporates into a low-temperature and low-pressure gas. The low-temperature and low-pressure gas is sucked into the compressor 350 again to start the next refrigeration cycle until the temperature value detected by the temperature sensor 127 is consistent with the set temperature value of the temperature controller 310.

[0076] In the heating mode, the compressor 350 compresses the refrigerant to increase its temperature and pressure. The temperature controller 310 adjusts the electromagnetic four-way valve 390 to connect the compressor 350 with the evaporator 380. The temperature controller 310 controls the electric heater 340 to energize and heat the heat exchange medium in the heat exchange medium container 320. The compressor 350 is turned on, and the high-temperature and high-pressure refrigerant is sent to the evaporator 380, where the high-temperature and high-pressure refrigerant releases heat to increase the temperature of the heat exchange medium in the heat exchange medium container 320. The circulating pump 330 sends the heated heat exchange medium into the heat exchange pipeline 114 for circulation, so that the heat exchange pipeline 114 can exchange heat with the electrolyte in the inner container 110, so that the temperature of the electrolyte in the inner container 110 increases. At the same time, the refrigerant in the evaporator 380 becomes a high-pressure liquid. Next, the high-pressure liquid passes through the expansion valve 370, and the pressure and temperature are reduced. The low-temperature and low-pressure refrigerant enters the condenser 360, where the low-temperature and low-pressure refrigerant absorbs heat from the external environment and becomes a low-temperature and low-pressure gas. Finally, the low-temperature and low-pressure gas is sucked into the compressor 350 again, and the next heating cycle begins until the temperature value detected by the temperature sensor 127 is consistent with the set temperature value of the temperature controller 310.

[0077] In an embodiment of the present application, the several functional ports on the tank body 100 may include but are not limited to a liquid outlet 115 , a liquid inlet 116 , a liquid mixing port 117 , a liquid level balance port 118 , a safety valve port 120 , a nitrogen charging port 121 , a liquid replenishing port 122 and a manhole 123 .

[0078] See also Figure 6In one embodiment, the liquid outlet 115 is disposed at the bottom of the tank body 100. Preferably, the liquid outlet 115 may be provided on the side wall of the tank body 100 near the bottom. The liquid outlet 115 is used to connect the liquid outlet pipe 30 and the interior of the inner container 110, and the liquid outlet pipe 30 is used to output the electrolyte in the inner container 110. For example, a liquid suction pump 31 may be provided on the liquid outlet pipe 30, and the electrolyte in the inner container 110 can be more effectively pumped into the stack unit 20 through the liquid suction pump 31.

[0079] Since the volume of the entire tank 100 is relatively large, the problem of electrolyte deposition is likely to occur. Figure 6 and Figure 8 In one embodiment, the electrolyte storage tank 10 further includes a main pipeline 124 and a plurality of branch pipelines 125 disposed in the inner container 110. The main pipeline 124 is disposed in the inner container 110 and close to the bottom of the inner container 110, and the outlet end of the main pipeline 124 penetrates the side wall of the tank body 100 and forms a liquid outlet 115. The plurality of branch pipelines 125 are evenly arranged at the bottom of the inner container 110. The plurality of branch pipelines 125 are all structures with one end open, and the open end of each branch pipeline 125 is connected to the main pipeline 124, and each branch pipeline 125 is provided with a plurality of liquid suction holes 126.

[0080] like Figure 6 and Figure 8 As shown, in one embodiment, the main pipeline 124 can be an annular pipe. The annular pipe is arranged to extend along the circumference of the inner container 110. The annular pipe has an outlet end that penetrates the side wall of the tank body 100. Each branch pipeline 125 can be a curved pipe that matches the bottom shape of the inner container 110. The open end of each branch pipeline 125 is connected to the annular pipe. The length extension directions of multiple branch pipelines 125 can intersect at one point.

[0081] like Fig. 9 and Fig.10 As shown, in one embodiment, the main pipeline 124 can be a roughly L-shaped curved pipe. One end thereof penetrates the side wall of the tank body 100 and forms a liquid outlet 115, and the other end extends downward to the bottom wall of the inner container 110. Each branch pipeline 125 can be an arc-shaped pipe that matches the shape of the bottom end cap of the inner container 110. The open end of each branch pipeline 125 is connected to one end of the main pipeline 124 extending to the bottom wall of the inner container 110. The length extension directions of multiple branch pipelines 125 can intersect at one point.

[0082] The plurality of liquid suction holes 126 on each branch pipeline 125 can be evenly arranged along the length direction of the branch pipeline 125. The plurality of liquid suction holes 126 can achieve uniform liquid suction and play a stirring role at the same time. Thus, the electrolyte at the bottom of the inner container 110 can be evenly mixed through the main pipeline 124 and the plurality of branch pipelines 125 to avoid electrolyte deposition.

[0083] In the embodiment of the present application, the liquid outlet 115 is arranged on the side wall of the tank body 100 and cooperates with the main pipeline 124 and multiple branch pipelines 125 to ensure that all the electrolyte at the bottom of the inner container 110 participates in the circulation process, reducing the risk of electrolyte deposition.

[0084] In other embodiments, the liquid outlet 115 may also be opened at the bottom of the tank body 100 to facilitate the electrolyte in the inner container 110 to be discharged outward as completely as possible.

[0085] See also Figure 3 In one embodiment, the liquid inlet 116 is disposed on the top of the tank body 100 . There may be multiple liquid inlets 116 , which are evenly spaced on the top of the tank body 100 .

[0086] The liquid inlet 116 is used to connect the liquid return pipe 40 and the interior of the inner container 110, and the liquid return pipe 40 is used to return the electrolyte to the inner container 110. For example, one end of the liquid return pipe 40 can be connected to a diverter, and the liquid return pipe 40 can be connected to multiple liquid inlets 116 through the diverter, so that the electrolyte can be uniformly returned to the inner container 110.

[0087] like Figure 3 As shown, in one embodiment, a safety valve port 120 is further provided on the top of the tank body 100. The safety valve port 120 is used to connect to the safety valve. By opening the safety valve port 120 on the tank body 100 and connecting to the safety valve, the pressure inside the inner container 110 can be adjusted to ensure that the pressure inside the inner container 110 is within a preset pressure value range, thereby preventing the pressure inside the inner container 110 from being too high or too low, causing electrolyte leakage.

[0088] In some other embodiments, the safety valve port 120 may also serve as a backup port.

[0089] In some other implementations, see Fig.12 As shown, a safety valve 13 can be provided on the liquid return pipe 40. When the battery system runs to a certain extent, the liquid in the inner container 110 decreases and the gas increases, and the excess gas can overflow from the safety valve 13 along the liquid return pipe 40 to adjust the internal pressure of the inner container 110.

[0090] In one embodiment, the electrolyte storage tank 10 further includes an exhaust gas collection pipeline 80, one end of which is connected to the safety valve port 120, and the other end of the exhaust gas collection pipeline 80 is used to connect to the exhaust gas treatment device 90. By providing the exhaust gas collection pipeline 80 and connecting it to the exhaust gas treatment device 90, the harmful gas formed in the inner container 110 can be collected and treated to avoid direct discharge into the atmosphere to cause environmental damage.

[0091] In other embodiments, see Fig.12As shown, the waste gas collecting pipeline 80 may also be connected to the safety valve 13 disposed on the liquid return pipe 40 to collect the waste gas overflowing from the safety valve 13 .

[0092] See also Figure 3 In one embodiment, a nitrogen filling port 121 is provided at the top of the tank body 100, and the nitrogen filling port 121 is used to connect the nitrogen filling pipeline. By providing the nitrogen filling port 121, an inert gas such as nitrogen can be introduced into the inner container 110 to achieve isolation of the electrolyte from the air, and at the same time, the pressure inside the inner container 110 can be regulated. It can be understood that the pipeline connected to the nitrogen filling port 121 includes but is not limited to being filled with inert gases such as nitrogen, and it can be filled with other types of gases as needed.

[0093] See also Figure 3 In one embodiment, a liquid replenishing port 122 is provided on the top of the tank body 100, and the liquid replenishing port 122 is used to connect the liquid replenishing pipeline 70. By providing the liquid replenishing port 122, the liquid replenishing pipeline 70 can be connected to replenish the electrolyte stock solution, such as hydrochloric acid, into the inner container 110.

[0094] An automatic refilling valve may be provided at the refilling port 122. The automatic refilling valve is provided with a pressure sensor, which can detect the pressure change in the inner container 110. When the pressure in the inner container 110 reaches a set value, the automatic refilling valve automatically opens to allow hydrochloric acid to enter the inner container 110 to complete the refilling.

[0095] In other embodiments, the automatic refilling valve may also be provided on the refilling pipeline 70 .

[0096] See also Figure 3 In one embodiment, a manhole 123 is provided at the top of the tank body 100. By providing the manhole 123, the manhole 123 can be used as an entrance and exit for maintenance of the electrolyte storage tank 10, and maintenance personnel can enter and exit the interior of the electrolyte storage tank 10 through the manhole 123. It can be understood that a detachable or flip-openable manhole cover can be provided at the manhole 123 on the top of the tank body 100.

[0097] See also Fig.12 In one embodiment, a mixing port 117 is provided on the side wall of the tank body 100. The mixing port 117 can be provided at the middle and upper part of the side wall of the tank body 100. The mixing port 117 is used to connect the mixing pipe 50, and the mixing pipe 50 is used to connect the inner container 110 storing electrolytes of different polarities. In this embodiment, by providing the mixing port 117 on the tank body 100, it can be used to connect the mixing pipe 50 to achieve the mixing of the positive electrode electrolyte and the negative electrode electrolyte, and balance the liquid level in the storage tank storing electrolytes of different polarities, which is beneficial to the long-term efficient and stable operation of the battery system.

[0098] See also Fig.12In one embodiment, the electrolyte storage tank 10 further includes a liquid level gauge 14, which is disposed on the tank body 100 and is used to detect the liquid level in the inner container 110. The liquid level gauge 14 can be various types of liquid level gauges, such as a tube liquid level gauge, a differential pressure liquid level gauge, or a float liquid level gauge.

[0099] See also Figure 6 As shown, in one embodiment, a liquid level balance port 118 is provided on the side wall of the tank body 100. There may be multiple liquid level balance ports 118. The multiple liquid level balance ports 118 may be respectively opened at the upper position and the lower position of the tank body 100. The liquid level balance port 118 is used to connect to the liquid level balance pipe 60, and the liquid level balance pipe 60 is used to connect to the inner container 110 storing electrolytes of the same polarity.

[0100] In this embodiment, by providing a liquid level balance port 118 on the tank body 100, it can be used to connect the liquid level balance pipe 60 to achieve mutual circulation of positive electrolytes in different storage tanks and mutual circulation of negative electrolytes in different storage tanks. In this way, multiple storage tanks can be connected in parallel to supply positive electrolytes or negative electrolytes, which is conducive to the long-term efficient and stable operation of the battery system.

[0101] See also Fig.12 and Fig.13 As shown, in one embodiment of the present invention, a flow battery energy storage system is also provided, comprising a battery stack unit 20 and at least two electrolyte storage tanks 10. The electrolyte storage tank 10 is the electrolyte storage tank 10 of any of the above embodiments.

[0102] The stack unit 20 is provided with a positive electrode inlet, a positive electrode outlet, a negative electrode inlet and a negative electrode outlet. The at least two electrolyte storage tanks 10 include a first electrolyte storage tank 11 for storing positive electrode electrolyte and a second electrolyte storage tank 12 for storing negative electrode electrolyte.

[0103] like Fig.12 As shown, in one embodiment of the present application, the flow battery energy storage system includes a battery stack unit 20 , a first electrolyte storage tank 11 and a second electrolyte storage tank 12 .

[0104] The liquid outlet 115 of the first electrolyte storage tank 11 is connected to the positive electrode inlet, and the liquid inlet 116 of the first electrolyte storage tank 11 is connected to the positive electrode outlet. The liquid outlet 115 of the second electrolyte storage tank 12 is connected to the negative electrode inlet, and the liquid inlet 116 of the second electrolyte storage tank 12 is connected to the negative electrode outlet.

[0105] In this embodiment, the charge and discharge reaction of the flow battery system is realized by continuously allowing the positive electrode electrolyte in the first electrolyte storage tank 11 and the negative electrode electrolyte in the second electrolyte storage tank 12 to enter the stack unit 20. The stack unit 20 may be a conventional structure in which the positive electrode and the negative electrode are separated by a diaphragm.

[0106] like Fig.12 As shown, in one embodiment, the liquid flow battery energy storage system further includes a mixing pipe 50, one end of which is connected to the first electrolyte storage tank 11, and the other end is connected to the second electrolyte storage tank 12. In this embodiment, by providing the mixing pipe 50 to connect the first electrolyte storage tank 11 and the second electrolyte storage tank 12, the positive electrode electrolyte and the negative electrode electrolyte can be mixed, and the liquid levels of the first electrolyte storage tank 11 and the second electrolyte storage tank 12 can be balanced, which is conducive to the long-term, efficient and stable operation of the energy storage system.

[0107] Furthermore, the liquid flow battery energy storage system also includes a control valve 51, which is arranged on the mixing pipe 50 and is used to control the conduction and cutoff of the mixing pipe 50. In this embodiment, the conduction of the mixing pipe 50 can be controlled by the control valve 51. When the liquid level difference between the first electrolyte storage tank 11 and the second electrolyte storage tank 12 is large, the mixing pipe 50 can be turned on by the control valve 51, so that the positive electrolyte in the first electrolyte storage tank 11 and the negative electrolyte in the second electrolyte storage tank 12 can flow to each other until the liquid levels of the first electrolyte storage tank 11 and the second electrolyte storage tank 12 are the same. At this time, the mixing pipe 50 can be cut off by the control valve 51.

[0108] like Fig.13 As shown, in another embodiment of the present application, the liquid flow battery energy storage system includes a battery stack unit 20, two first electrolyte storage tanks 11 and two second electrolyte storage tanks 12.

[0109] The liquid outlets 115 of the two first electrolyte storage tanks 11 are respectively connected to the positive electrode inlet, and the liquid inlets 116 of the two first electrolyte storage tanks 11 are respectively connected to the positive electrode outlet. The liquid outlets 115 of the two second electrolyte storage tanks 12 are respectively connected to the negative electrode inlet, and the liquid inlets 116 of the two second electrolyte storage tanks 12 are respectively connected to the negative electrode outlet.

[0110] In this embodiment, two first electrolyte storage tanks 11 are arranged in parallel. The two first electrolyte storage tanks 11 can simultaneously circulate and supply positive electrode electrolyte to the stack unit 20. Alternatively, each first electrolyte storage tank 11 can circulate and supply positive electrode electrolyte to the stack unit 20 separately.

[0111] The two second electrolyte storage tanks 12 are arranged in parallel. The two second electrolyte storage tanks 12 can simultaneously circulate and supply the negative electrode electrolyte to the stack unit 20. Alternatively, each second electrolyte storage tank 12 can circulate and supply the negative electrode electrolyte to the stack unit 20 separately.

[0112] like Fig.13 As shown, in one embodiment, the liquid flow battery energy storage system further includes a liquid level balance tube 60. Both ends of the liquid level balance tube 60 are respectively connected to the two first electrolyte storage tanks 11 to balance the liquid levels of the two first electrolyte storage tanks 11. The liquid level balance tube 60 can keep the liquid level in each first electrolyte storage tank 11 balanced, which is beneficial to improve the energy storage efficiency.

[0113] like Fig.13 As shown, both ends of the liquid level balance tube 60 are respectively connected to the two second electrolyte storage tanks 12 to balance the liquid levels of the two second electrolyte storage tanks 12. The liquid level balance tube 60 can keep the liquid level in each second electrolyte storage tank 12 balanced, which is beneficial to improve the energy storage efficiency.

[0114] It can be understood that in other embodiments, the liquid flow battery energy storage system may include a battery stack unit 20, a first electrolyte storage tank 11, and a plurality of second electrolyte storage tanks 12. Alternatively, the liquid flow battery energy storage system may include a battery stack unit 20, a plurality of first electrolyte storage tanks 11, and a second electrolyte storage tank 12. Alternatively, the liquid flow battery energy storage system may include a battery stack unit 20, a plurality of first electrolyte storage tanks 11, and a plurality of second electrolyte storage tanks 12. That is, the liquid flow battery energy storage system of the present application can combine any number of positive electrode electrolyte storage tanks 10 with any number of negative electrode electrolyte storage tanks 10 to achieve a variety of combinations of one-to-one, one-to-many, and many-to-many.

[0115] like Fig.12 As shown, in one embodiment, the liquid flow battery energy storage system further includes a refilling pipeline 70. The refilling pipeline 70 can be connected to the first electrolyte storage tank 11 and the second electrolyte storage tank 12 respectively. The refilling pipeline 70 is used to replenish the electrolyte stock solution, such as hydrochloric acid, into the first electrolyte storage tank 11 and the second electrolyte storage tank 12.

[0116] like Fig.12 As shown, in one embodiment, the liquid flow battery energy storage system further includes an exhaust gas collection pipeline 80. The exhaust gas collection pipeline 80 can be connected to the first electrolyte storage tank 11 and the second electrolyte storage tank 12 respectively. Specifically, one end of the exhaust gas collection pipeline 80 is connected to the safety valve 13 provided on the return pipe 40 of the first electrolyte storage tank 11 and the second electrolyte storage tank 12 respectively to collect the exhaust gas overflowing from the safety valve 13. The other end of the exhaust gas collection pipeline 80 is connected to the exhaust gas treatment device 90. Among them, the first electrolyte storage tank 11 and the second electrolyte storage tank 12 can share a set of exhaust gas treatment devices 90.

[0117] like Fig.11 and Fig.12 As shown, in one embodiment of the present application, the flow battery energy storage system may include a temperature control unit 300. The temperature control unit 300 can enter different working modes according to the difference between the set temperature value of the temperature controller 310 and the temperature value detected by the temperature sensor 127, thereby controlling the heat exchange pipeline 114 to exchange heat with the electrolyte in the inner container 110 to achieve precise temperature control. The detailed process can be found in the relevant description above, which will not be repeated here.

[0118] See also Fig.12 and Fig.13 As shown, the operation mode of the flow battery energy storage system of the embodiment of the present application can be:

[0119] During the operation of the system, the control temperature of the temperature controller 310 can be set at 40° C. The temperature control unit 300 , the temperature sensor 127 and the heat exchange pipeline 114 can accurately control the electrolyte in the inner container 110 to maintain the set temperature, so as to maintain the highest battery efficiency.

[0120] When the system is running, the positive electrode electrolyte in the first electrolyte storage tank 11 is output to the battery stack unit 20 through the liquid outlet pipe 30 and under the action of the liquid suction pump 31, and the negative electrode electrolyte in the second electrolyte storage tank 12 is output to the battery stack unit 20 through the liquid outlet pipe 30 and under the action of the liquid suction pump 31, and the positive electrode electrolyte and the negative electrode electrolyte undergo an electrochemical reaction in the battery stack unit 20.

[0121] The positive electrode electrolyte after the reaction is evenly distributed through the return pipe 40 and returned to the first electrolyte storage tank 11 from the various liquid inlets 116 on the top of the tank body 100. The negative electrode electrolyte after the reaction is evenly distributed through the return pipe 40 and returned to the second electrolyte storage tank 12 from the various liquid inlets 116 on the top of the tank body 100, thereby forming a closed circulation liquid flow loop.

[0122] During the liquid circulation process, the liquid level can be observed by the liquid level gauge 14 in the first electrolyte storage tank 11 and the second electrolyte storage tank 12. When the liquid levels of the first electrolyte storage tank 11 and the second electrolyte storage tank 12 are unbalanced, the energy storage efficiency will be seriously affected, causing electrolyte short-circuiting. At this time, the control valve 51 is opened to make the mixing pipe 50 conductive, so that the liquid level of the first electrolyte storage tank 11 and the second electrolyte storage tank 12 can be balanced, ensuring the long-term and efficient operation of the system. After the liquid levels of the two are balanced, the control valve 51 is closed.

[0123] like Fig.13As shown, when there are multiple first electrolyte storage tanks 11, each first electrolyte storage tank 11 can achieve liquid level balance under the connection of the liquid level balance pipe 60, which is conducive to improving energy storage efficiency and ensuring long-term efficient operation of the system. When there are multiple second electrolyte storage tanks 12, each second electrolyte storage tank 12 can achieve liquid level balance under the connection of the liquid level balance pipe 60, which is conducive to improving energy storage efficiency and ensuring long-term efficient operation of the system.

[0124] like Fig.12 As shown, the return pipes 40 of the first electrolyte storage tank 11 and the second electrolyte storage tank 12 may be provided with safety valves 13, respectively. One end of the waste gas collection pipeline 90 is wrapped and arranged outside the safety valve 13. When the hydrochloric acid volatilizes more and the pressure in the return pipe 40 is higher, the safety valve 13 will be opened to allow the gas to overflow. The overflowed hydrochloric acid waste gas flows through the waste gas collection pipeline 90 to the waste gas treatment device 91 for neutralization treatment, so that the hydrochloric acid waste gas can be well collected to reduce environmental damage.

[0125] like Fig.12 As shown, the refilling ports 122 at the top of the tank bodies 100 of the first electrolyte storage tank 11 and the second electrolyte storage tank 12 may be respectively provided with automatic refilling valves, and the automatic refilling valves are connected to the refilling pipeline 70. A pressure sensor is provided inside the automatic refilling valve, and the non-nitrogen filling time pressure sensor can detect the pressure change in the inner container 110. When the pressure change fluctuates greatly, it means that the hydrochloric acid vapor is continuously discharged at this time, and the automatic refilling valve will automatically open to quantitatively replenish hydrochloric acid into the inner container 110. At the same time, the nitrogen filling port 121 can be appropriately pressurized to promote uniform mixing of the electrolyte in the inner container 110.

[0126] The above embodiments are merely exemplary descriptions of the structures. The structures in the embodiments are not fixed combination structures. In the absence of structural conflicts, the structures in multiple embodiments can be used in any combination.

[0127] Although the present invention has been described with reference to several typical embodiments, it should be understood that the terms used are illustrative and exemplary, rather than restrictive. Since the present invention can be embodied in a variety of forms without departing from the spirit or essence of the invention, it should be understood that the above embodiments are not limited to any of the foregoing details, but should be interpreted broadly within the spirit and scope defined by the appended claims, so all changes and modifications falling within the scope of the claims or their equivalents should be covered by the appended claims.

Claims

1. An electrolyte storage tank, characterized in that: include: A tank body, comprising an inner container and an outer jacket wrapped around the inner container, wherein the inner container is used to store electrolyte, the inner container is made of metal, the inner wall of the inner container is coated with a coating, the outer jacket is made of non-metallic material, and there is a gap between the outer jacket and the inner container to form an installation space; a heat exchange pipeline, which is arranged in the installation space between the outer jacket and the inner container, and is used for circulating a heat exchange medium; a liquid outlet, which is arranged at the bottom of the tank body, the liquid outlet is used to connect a liquid outlet pipe with the interior of the inner container, and the liquid outlet pipe is used to output the electrolyte in the inner container; A liquid inlet is arranged at the top of the tank body, and the liquid inlet is used to connect the liquid return pipe and the interior of the inner container, and the liquid return pipe is used to allow the electrolyte to flow back into the inner container.

2. The electrolyte storage tank according to claim 1, characterized in that: It also includes a liquid mixing port, which is arranged on the side wall of the tank body. The liquid mixing port is used to connect to a liquid mixing pipe, and the liquid mixing pipe is used to connect to the inner container storing electrolytes of different polarities.

3. The electrolyte storage tank according to claim 1, characterized in that: It also includes a liquid level balance port, which is arranged on the side wall of the tank body. The liquid level balance port is used to connect to a liquid level balance pipe, and the liquid level balance pipe is used to connect to the inner container storing electrolytes of the same polarity.

4. The electrolyte storage tank according to claim 1, characterized in that: It also includes a liquid level meter, which is arranged on the tank body and is used to detect the liquid level in the inner container.

5. The electrolyte storage tank according to claim 1, characterized in that: Also includes: A main pipe, the main pipe is arranged in the inner container and close to the bottom of the inner container, and the outlet end of the main pipe penetrates the side wall of the tank body and forms the liquid outlet; A plurality of branch pipelines are evenly arranged at the bottom of the inner container, each of the branch pipelines is open at one end, the open end of each branch pipeline is connected to the main pipeline, and each branch pipeline is provided with a plurality of liquid inlet holes.

6. The electrolyte storage tank according to claim 1, characterized in that: It also includes a liquid leakage sensor, which is arranged at the bottom of the tank body and located in the installation space between the outer jacket and the inner container.

7. The electrolyte storage tank according to claim 1, characterized in that: It also includes a safety valve port, which is arranged on the top of the tank body and is used to connect to a safety valve and / or an exhaust gas collection pipeline.

8. The electrolyte storage tank according to claim 1, characterized in that: It also includes a nitrogen filling port, which is arranged on the top of the tank body and is used to connect to a nitrogen filling pipeline; A liquid infusion port, the liquid infusion port is arranged on the top of the tank body, and the liquid infusion port is used to connect to the liquid infusion pipeline; A manhole is arranged on the top of the tank body.

9. The electrolyte storage tank according to claim 1, characterized in that: Also included is a frame, which is connected to the outside of the outer jacket.

10. A liquid flow battery energy storage system, comprising a battery stack unit and at least two electrolyte storage tanks, characterized in that: The electrolyte storage tank is the electrolyte storage tank according to any one of claims 1 to 9; The stack unit is provided with a positive electrode inlet, a positive electrode outlet, a negative electrode inlet and a negative electrode outlet; The at least two electrolyte storage tanks include a first electrolyte storage tank for storing positive electrode electrolyte and a second electrolyte storage tank for storing negative electrode electrolyte; The liquid outlet of the first electrolyte storage tank is communicated with the positive electrode inlet, and the liquid inlet of the first electrolyte storage tank is communicated with the positive electrode outlet; The liquid outlet of the second electrolyte storage tank is communicated with the negative electrode inlet, and the liquid inlet of the second electrolyte storage tank is communicated with the negative electrode outlet.

11. The liquid flow battery energy storage system according to claim 10, characterized in that: It also includes a mixing pipe and a control valve, one end of the mixing pipe is connected to the first electrolyte storage tank, and the other end is connected to the second electrolyte storage tank. The control valve is arranged on the mixing pipe to control the conduction and cutoff of the mixing pipe.

12. The liquid flow battery energy storage system according to claim 10, characterized in that: It also includes a liquid level balance pipe, both ends of which are connected to the two first electrolyte storage tanks respectively; and / or Both ends of the liquid level balance tube are respectively connected to the two second electrolyte storage tanks.

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