Self-sensing anticorrosion sealing structure of liquid flow battery underground energy storage chamber and construction method thereof

Abstract

The application relates to the technical field of underground energy storage engineering and corrosion prevention, and particularly discloses a liquid flow battery underground energy storage chamber self-sensing corrosion prevention sealing structure and a construction method thereof. A three-layer composite gradient structure composed of an insulating leveling bottom layer, a conductive reinforcing layer and a semi-conductive detection surface layer is arranged on the inner wall surface of a chamber concrete structure layer, and a pre-embedded electrode array is arranged between the semi-conductive detection surface layer and the conductive reinforcing layer. The microprocessor and the wireless transmission module in the ground data acquisition box are matched, the problems of insufficient bonding strength between the underground chamber corrosion prevention coating and the concrete, the formation of a primary battery loop between the conductive filler and the steel bars in a humid environment to accelerate corrosion, the lack of deformation coordination ability of the coating and the difficulty in real-time monitoring and positioning after the coating fails are solved, real-time sensing of the health state of the coating and accurate positioning of the damage area are realized, the corrosion prevention reliability and operation safety of the liquid flow battery underground energy storage chamber are improved, and the maintenance difficulty and the electrolyte leakage risk after the coating fails are reduced.

Description

Technical Field

[0001] This invention relates to the fields of underground energy storage engineering and corrosion prevention technology, and in particular to a self-sensing corrosion-resistant sealing structure for underground energy storage chambers of flow batteries and its construction method. Background Technology

[0002] Flow batteries, especially vanadium redox flow batteries, have become an important technology for large-scale, long-term energy storage due to their advantages such as long cycle life, high safety, and independent design of power and capacity. However, as energy storage scales expand to the megawatt and even gigawatt levels, existing ground-based storage tank solutions have revealed significant shortcomings. The volume of a single ground-based storage tank is typically no more than 50-100 m³. 3 A 300MW / 1200MWh system requires approximately 50,000 to 60,000 m³ / h. 3 The electrolyte requires hundreds of storage tanks connected in parallel, resulting in an extremely complex piping system. The potential difference and circulating current between these parallel tanks are difficult to suppress effectively. Furthermore, the above-ground storage tanks occupy a huge area; for example, a 100-megawatt power plant in a certain region has over 700 large storage tanks and over 300 containers occupying approximately 24,500 square meters. 2 In the land-scarce central and eastern regions and surrounding urban areas, there is a lack of available land. The circulating current caused by the potential difference between tanks can lead to a 2%–5% loss in system efficiency, and can also cause localized overheating of the electrolyte and accelerated electrode corrosion. Furthermore, surface storage tanks are exposed to the natural environment, with temperature control energy consumption accounting for 10%–15% of the system's operating costs. The electrolyte is also rich in sulfuric acid and heavy metal ions, posing a high risk of leakage. The large complex of hundreds of tanks can easily trigger NIMBY (Not In My Backyard) effects, increasing the difficulty of site selection and approval.

[0003] Utilizing artificially excavated or constructed underground chambers to store electrolytes is an effective way to achieve large-scale development of flow batteries. Artificial chambers can provide a single storage capacity of tens to hundreds of thousands of m³, simplifying hundreds of storage tanks into one or two underground chambers, fundamentally simplifying the piping system and eliminating parallel circulation interference. Underground storage encloses the electrolyte underground, leaving only a few equipment entrances and exits on the surface, occupying less than 10% of the land area of ​​surface-based solutions. The ground temperature at a depth of 20-50 meters remains stable at 15-20℃ year-round, almost unaffected by surface temperature changes, significantly reducing temperature control energy consumption by approximately 30%-50%, while avoiding the risks of high-temperature precipitation and low-temperature crystallization. The natural protective and isolation capabilities of underground space enable seamless construction of energy storage facilities, eliminating visual pollution and NIMBY (Not In My Backyard) effects from the outset.

[0004] However, underground liquid storage also presents technical challenges that surface solutions cannot address. Underground chambers are primarily lined with concrete or supported by shotcrete and anchors, with porous surfaces and high water content. Conventional anti-corrosion coatings typically have a bonding strength of less than 5 MPa with concrete, making them prone to peeling after long-term service. In underground environments, once the outer wall protection fails, groundwater seeps into the concrete, altering its ionic conductivity. If the anti-corrosion layer uses conductive fillers such as graphene, it may form a galvanic cell circuit with the reinforcing steel in the concrete, accelerating steel corrosion. During operation, underground chambers are subjected to minute deformations caused by surrounding rock creep, foundation settlement, and fluctuations in air and liquid levels, requiring the anti-corrosion layer to possess sufficient flexibility, with an elongation at break of 5%–10% to accommodate deformation. Furthermore, the limited space for maintenance within the chamber makes operations difficult, and the failure of the anti-corrosion layer is hard to detect and address. Therefore, real-time monitoring of the coating's health status and support for rapid localized repairs are essential. The total acidity of the electrolyte in a vanadium redox flow battery is about 4~5 mol / L, and it contains pentavalent vanadium ions with strong oxidizing properties. Conventional anti-corrosion coatings are prone to oxidation degradation and blistering and peeling under long-term immersion, making it difficult to meet the service life requirement of 20~30 years.

[0005] Currently available anti-corrosion coatings for underground tunnels, such as epoxy coal tar coatings, glass flake coatings, and polyurea elastomers, cannot systematically address the aforementioned complex challenges. Existing coatings are mostly single, homogeneous structures, making it difficult to simultaneously meet multiple requirements such as adhesion, insulation, conductive shielding, monitoring, and deformation coordination. While some research has incorporated graphene into coatings to improve anti-corrosion performance, the side effect of its conductivity accelerating steel corrosion in humid environments has not been considered. Current technologies lack intelligent monitoring capabilities, failing to detect the coating's health status in real time for early warning of leakage risks, and also neglecting maintainability, making repair difficult after overall coating failure. Furthermore, existing technologies have not been systematically optimized for the strong oxidizing characteristics of flow battery electrolytes, and their tolerance to pentavalent vanadium ions is insufficiently verified. Therefore, developing an anti-corrosion sealing system based on a systematic structural design rather than relying on specific material formulations, achieving integrated protection throughout the entire lifecycle (prevention, monitoring, and repair), is crucial for promoting the large-scale application of flow battery underground energy storage technology. Summary of the Invention

[0006] To address the aforementioned technical problems, this invention provides a self-sensing anti-corrosion sealing structure for underground energy storage chambers of flow batteries and its construction method.

[0007] In a first aspect, the present invention provides a self-sensing anti-corrosion sealing structure for underground energy storage chambers of flow batteries, the technical solution of which is as follows: Includes: a three-layer composite coating on the inner wall and a waterproof and anti-corrosion layer on the outer wall; The inner wall three-layer composite coating is applied to the inner wall surface of the chamber concrete structure layer; the outer wall waterproof and anti-corrosion layer is applied to the outer surface of the chamber concrete structure layer. The inner wall three-layer composite coating is a three-layer composite gradient structure. The three-layer composite gradient structure consists of an insulating leveling base layer, a conductive reinforcement layer, and a semi-conductive detection surface layer, which are arranged sequentially from the inner wall surface of the concrete structure layer of the chamber outwards. The insulating leveling bottom layer is an insulating coating without conductive filler, the conductive reinforcement layer is a conductive coating containing conductive filler, and the semi-conductive detection surface layer is a semi-conductive coating containing conductive filler. An embedded electrode array is pre-embedded between the semiconductive detection surface layer and the conductive reinforcement layer, and the embedded electrode array is led out to the ground data acquisition box through a corrosion-resistant wire; The ground data acquisition box has a built-in microprocessor and a wireless transmission module. The microprocessor is used to locate the damaged area of ​​the three-layer composite coating on the inner wall based on the resistance value change between each electrode in the pre-embedded electrode array. The wireless transmission module is used to send the information of the damaged area to the ground monitoring center.

[0008] The beneficial effects of the self-sensing anti-corrosion sealing structure for underground energy storage chambers of flow batteries according to the present invention are as follows: This invention solves several problems by setting a three-layer composite gradient structure on the inner wall surface of the concrete structure layer of the underground chamber, consisting of an insulating leveling layer, a conductive reinforcement layer, and a semi-conductive detection layer. An embedded electrode array is set between the semi-conductive detection layer and the conductive reinforcement layer. Combined with a microprocessor and wireless transmission module in the ground data acquisition box, this invention addresses the issues of insufficient bonding strength between the anti-corrosion coating and concrete in underground chambers, accelerated corrosion caused by conductive fillers forming a galvanic circuit with steel bars in humid environments, lack of deformation coordination ability of the coating, and difficulty in real-time monitoring and location after failure. It achieves real-time perception of the coating's health status and precise location of damaged areas, improving the anti-corrosion reliability and operation and maintenance safety of the flow battery underground energy storage chamber, and reducing the difficulty of repair and the risk of electrolyte leakage after coating failure.

[0009] Based on the above solution, the self-sensing anti-corrosion sealing structure for underground energy storage chambers of flow batteries of the present invention can be further improved as follows.

[0010] In one alternative embodiment, the concrete structure layer of the chamber is located in a soil-soft rock chamber. The concrete structure layer includes an initial support and a secondary lining. The initial support is located on the inner surface of the soil-soft rock surrounding rock and is a combination structure of shotcrete layer and steel arch frame. The secondary lining is a cast-in-place reinforced concrete lining located on the inner surface of the initial support. A three-layer composite coating is applied to the inner surface of the secondary lining. An outer waterproof and anti-corrosion layer is applied between the outer surface of the secondary lining and the inner surface of the initial support.

[0011] The beneficial effects of adopting the above-mentioned optional method are as follows: In view of the geological characteristics of soil and soft rock chambers, a layered bearing system is formed by initial support and secondary lining. The outer wall waterproof and anti-corrosion layer is set between the outer surface of the secondary lining and the initial support, so that the inner wall three-layer composite coating and the outer wall waterproof and anti-corrosion layer act on different structural layers respectively, realizing internal and external layered protection and adapting to the deformation requirements of soft rock strata.

[0012] In one alternative embodiment, the concrete structure layer of the chamber is located in a hard rock chamber. The concrete structure layer is a shotcrete and anchor support structure, which is disposed on the inner surface of the hard rock surrounding rock. The shotcrete and anchor support structure is a combination of a shotcrete layer and a system of anchor bolts. The inner wall three-layer composite coating is disposed on the inner wall surface of the shotcrete and anchor support structure. The outer wall waterproof and anti-corrosion layer is a partial outer wall waterproof and anti-corrosion layer, which is disposed between the outer surface of the shotcrete and anchor support structure and the inner surface of the hard rock surrounding rock, and is only disposed in the groundwater-developed section.

[0013] The advantages of adopting the above-mentioned optional methods are as follows: for the surrounding rock conditions of hard rock chambers, the shotcrete and anchor support structure is used as the concrete structural layer, and the outer wall waterproof and anti-corrosion layer is only set in the groundwater development section, avoiding unnecessary construction in dry rock areas. While reducing material consumption and construction costs, the waterproof and anti-corrosion effect of key seepage parts is guaranteed.

[0014] In one alternative embodiment, the insulating leveling substrate is made of silicone-modified epoxy resin or phenolic epoxy resin, and contains insulating filler. The insulating leveling substrate is used to fill micro-cracks and pores on the surface of the chamber concrete structure layer to provide a smooth base surface. The insulating leveling substrate is used to isolate the electrical contact between the conductive reinforcement layer and the chamber concrete structure layer.

[0015] The beneficial effects of adopting the above-mentioned optional method are as follows: by using organosilicon-modified epoxy resin or phenolic epoxy resin as the insulating leveling substrate material and incorporating insulating fillers, an electrical insulating isolation layer is formed on the basis of filling micro-cracks and holes on the concrete surface to provide a flat base surface, thereby blocking the electrical contact between the conductive reinforcement layer and the steel bars in the concrete structural layer and preventing the occurrence of galvanic corrosion reaction.

[0016] In one alternative embodiment, the resin matrix of the conductive reinforcement layer is a phenolic epoxy vinyl ester resin, wherein a toughening modifier and surface-modified graphene filler are added to the phenolic epoxy vinyl ester resin, and the graphene filler forms a two-dimensional sheet barrier structure in the conductive reinforcement layer. The two-dimensional sheet barrier structure is used to block the penetration of corrosive media, and the conductive reinforcement layer has flexibility to coordinate the deformation of the surrounding rock.

[0017] The beneficial effects of adopting the above-mentioned optional method are as follows: further using phenolic epoxy vinyl ester resin as the conductive reinforcing layer matrix, combined with toughening modifier and surface modified graphene filler, so that graphene forms a two-dimensional sheet barrier structure in the layer, extending the penetration path of corrosive media, while giving the coating flexibility to coordinate the deformation of the surrounding rock and avoid the coating from cracking and peeling off due to deformation.

[0018] In one alternative embodiment, the embedded electrode array is embedded at the interface between the semiconductive detection surface layer and the conductive reinforcement layer, wherein the electrode material of the embedded electrode array is the same as that of the semiconductive detection surface layer, and the embedded electrode array is arranged at equal intervals.

[0019] The advantages of adopting the above-mentioned optional method are as follows: the pre-embedded electrode array is further set at the interface between the semi-conductive detection surface layer and the conductive reinforcement layer. The electrode material is the same as the semi-conductive detection surface layer material and is arranged at equal intervals to ensure the consistency of electrical contact between the electrode and the detection surface layer, providing uniformly distributed sampling nodes for resistance monitoring and improving the damage location accuracy.

[0020] In one optional embodiment, the microprocessor is used to acquire the real-time resistance value between each electrode in the pre-embedded electrode array. The microprocessor is used to compare the real-time resistance value with the initial resistance value to obtain the resistance change rate. When the semiconductive detection surface layer is damaged and electrolyte seeps in, the resistivity of the semiconductive detection surface layer decreases. When the microprocessor determines that the resistance change rate exceeds a preset threshold, it generates an alarm signal. The wireless transmission module sends the alarm signal and information about the damaged area to the ground monitoring center.

[0021] The advantages of adopting the above optional method are as follows: the resistance change rate is obtained by comparing the real-time resistance value with the initial resistance value through the microprocessor. When the semiconductive detection surface layer is damaged and electrolyte seeps in, the resistivity decreases and triggers an alarm. The alarm signal and the information of the damaged area are transmitted wirelessly to the ground monitoring center to realize remote real-time monitoring of the coating health status.

[0022] In one optional approach, the preset threshold is a resistance value decrease exceeding 15%. The microprocessor uses a resistivity tomography algorithm or a localization algorithm based on the time difference of the first decrease in resistance between electrodes to calculate the location coordinates of the damaged area. The localization algorithm based on the time difference of the first decrease in resistance between electrodes is as follows: the electrolyte diffuses from the damaged point to the surrounding area, and the diffusion front passes through the areas where different electrodes are located in sequence. The resistance value of each electrode decreases in time sequence, and the absolute time of the first decrease in resistance of each electrode is recorded. The location coordinates of the leakage source are calculated based on the diffusion rate of the electrolyte in the medium and the absolute time.

[0023] The advantages of using the above-mentioned optional methods are as follows: further setting the resistance value drop of more than 15% as the alarm threshold, and using a resistance tomography algorithm or a positioning algorithm based on the time difference of the first drop in resistance between electrodes to calculate the coordinates of the leakage source by using the electrolyte diffusion rate and the time difference of the first drop in resistance of each electrode, thereby improving the accuracy of the damage area positioning.

[0024] In one alternative embodiment, a detachable inspection port is provided at the pipe penetration points and valve connections of the concrete structural layer of the chamber, and a sealing flange is provided at the detachable inspection port. The surface of the sealing flange is coated with the same coating system as the three-layer composite coating of the inner wall.

[0025] The advantages of adopting the above-mentioned optional method are as follows: a detachable inspection port is further provided at the pipe penetration point and valve connection point, and the same coating system as the three-layer composite coating on the inner wall is applied to the surface of the sealing flange, so that the inspection port area has the same anti-corrosion performance as the main coating, which facilitates the later local maintenance and quick replacement, and reduces the difficulty of maintenance operations.

[0026] Secondly, the present invention provides a construction method for a self-sensing anti-corrosion sealing structure for an underground energy storage chamber of a flow battery, which is applied to the self-sensing anti-corrosion sealing structure for an underground energy storage chamber of a flow battery provided by the present invention. The technical solution of this method is as follows: The inner wall surface of the concrete structure layer of the chamber is treated to remove dust and oil stains, so that the inner wall surface is dry and flat. The outer wall waterproof and anti-corrosion layer is constructed on the outer surface of the concrete structure layer of the chamber; The insulating leveling base layer, the conductive reinforcement layer, and the semi-conductive detection surface layer are sequentially constructed on the inner wall surface of the concrete structure layer of the chamber, and each layer is cured after construction. During the construction of the semi-conductive detection surface layer, the embedded electrode array is pre-embedded simultaneously, and the embedded electrode array is led out to the ground data acquisition box through the corrosion-resistant wire; Debug the microprocessor and the wireless transmission module, and set the initial resistance baseline and alarm threshold; The three-layer composite coating on the inner wall and the waterproof and anti-corrosion layer on the outer wall, after construction, shall be subject to overall acceptance.

[0027] The beneficial effects of the construction method of the self-sensing anti-corrosion sealing structure for underground energy storage chambers of flow batteries according to the present invention are as follows: The construction method of this invention follows a sequence of steps: base surface treatment, construction of the outer wall waterproof and anti-corrosion layer, sequential construction of the three inner wall coatings, simultaneous installation of the pre-embedded electrode array, debugging of monitoring equipment, and overall acceptance. This method solves the problems of reduced coating adhesion quality and monitoring failure caused by inadequate base surface treatment, unreasonable construction sequence of functional layers, and disconnection between monitoring element installation and coating construction in the construction of anti-corrosion coatings for underground chambers. It achieves a match between the construction steps and the functional gradient design of the anti-corrosion sealing structure, ensuring the interface bonding quality and thickness uniformity of the insulating leveling layer, conductive reinforcement layer, and semi-conductive detection surface layer after sequential formation. At the same time, by simultaneously completing the pre-embedding of the pre-embedded electrode array and the lead-out of the wires during the surface layer construction stage, it avoids structural damage to the formed coating caused by secondary grooving or post-embedding operations, ensuring the electrical contact stability between the electrode array and the semi-conductive detection surface layer and the reliability of monitoring data, thus improving the construction quality and long-term service performance of the anti-corrosion sealing structure of underground energy storage chambers.

[0028] The above description is merely an overview of the technical solution of the present invention. In order to better understand the technical means of the present invention, it can be implemented according to the contents of the specification. In order to make the above and other objects, features and advantages of the present invention more obvious and understandable, specific embodiments of the present invention are given below. Attached Figure Description

[0029] The accompanying drawings are for illustrative purposes only and are not intended to limit the invention. Furthermore, the same reference numerals denote the same parts throughout the drawings. In the drawings: Figure 1 This is a schematic diagram of an embodiment of a self-sensing anti-corrosion sealing structure for an underground energy storage chamber of a flow battery according to the present invention; Figure 2 A schematic diagram of a soil-soft rock chamber structure; Figure 3 This is a schematic diagram of a hard rock chamber structure. Figure 4 This is an enlarged schematic diagram of the interlayer structure of the three-layer composite coating on the inner wall; Figure 5 This is a schematic flowchart illustrating an embodiment of the construction method for a self-sensing anti-corrosion sealing structure for an underground energy storage chamber of a flow battery according to the present invention. Detailed Implementation

[0030] Exemplary embodiments of the invention will now be described in more detail with reference to the accompanying drawings. Although exemplary embodiments of the invention are shown in the drawings, it should be understood that the invention may be implemented in various forms and should not be limited to the embodiments set forth herein.

[0031] Figure 1This diagram illustrates a structural schematic of an embodiment of a self-sensing corrosion-resistant sealing structure for an underground energy storage chamber of a flow battery provided by the present invention. Figure 1 As shown, it includes: an inner wall three-layer composite coating 5 and an outer wall waterproof and anti-corrosion layer 4.

[0032] The inner wall three-layer composite coating 5 is applied to the inner wall surface of the chamber concrete structure layer; the outer wall waterproof and anti-corrosion layer 4 is applied to the outer surface of the chamber concrete structure layer.

[0033] The inner wall three-layer composite coating 5 refers to a multi-layer composite anti-corrosion structure installed on the inner wall surface of the concrete structure layer of the chamber. From the inner wall surface outward, it consists of an insulating leveling base layer 10, a conductive reinforcement layer 11, and a semi-conductive detection surface layer 12. The three layers together constitute a composite anti-corrosion sealing layer with gradient function. For example, in the underground energy storage project of vanadium redox flow battery in location A, the inner wall surface of the concrete structure layer of the chamber is coated with an inner wall three-layer composite coating 5. The total thickness of the coating is 3.0 mm, of which the insulating leveling base layer 10 has a thickness of 1.2 mm, the conductive reinforcement layer 11 has a thickness of 1.3 mm, and the semi-conductive detection surface layer 12 has a thickness of 0.5 mm. The three layers together resist the corrosion of the electrolyte. The concrete structure layer of the underground chamber refers to the load-bearing structural layer made of concrete material in the underground chamber, which serves as the inner wall support surface to withstand the pressure of the surrounding rock and provide storage space for electrolyte. For example, in the underground energy storage project of vanadium redox flow battery in location A, the concrete structure layer of the underground chamber is the shotcrete and anchor support structure 7 in the hard rock chamber. The structure is a combination of shotcrete layer and system anchor bolts, which is set on the inner surface of hard rock surrounding rock 6.

[0034] The outer wall waterproof and anti-corrosion layer 4 refers to a waterproof and anti-corrosion coating applied to the outer surface of the concrete structure layer of the chamber, used to prevent groundwater from seeping into the concrete structure layer and to block the risk of corrosion of the galvanic cell. For example, in the underground energy storage project of vanadium redox flow battery in area A, the outer surface of the concrete structure layer of the chamber is fully coated with the outer wall waterproof and anti-corrosion layer 4. The coating is an organosilicon modified waterproof and anti-corrosion coating with a thickness of 1.0 mm, which isolates the groundwater from the concrete structure layer of the chamber.

[0035] The inner wall three-layer composite coating 5 consists of an insulating leveling base layer 10, a conductive reinforcement layer 11, and a semi-conductive detection surface layer 12, arranged sequentially from the inner wall surface of the concrete structure layer of the chamber outwards.

[0036] Among them, the insulating leveling base layer 10 refers to the bottom layer structure of the three-layer composite coating 5 that is in direct contact with the inner wall surface of the concrete structure layer of the chamber. It is used to fill the micro-cracks and pores on the concrete surface to provide a flat base surface, and at the same time, it serves as an electrical insulation isolation layer to block the transmission path of electrons to the concrete and steel bars. For example, in the underground energy storage project of vanadium redox flow battery in location A, the insulating leveling base layer 10 is sprayed on the inner wall surface of the concrete structure layer of the chamber with a thickness of 1.2mm, which fills all the micro-cracks and pores on the concrete surface and makes it flat. The conductive reinforcement layer 11 refers to the middle layer structure in the three-layer composite coating 5 of the inner wall, which is set on the outer surface of the insulating leveling bottom layer 10. It contains conductive filler and has conductivity. It is used to block the penetration of corrosive media through the two-dimensional sheet barrier structure of the conductive filler and to provide mechanical reinforcement. For example, in the underground energy storage project of vanadium redox flow battery in location A, the conductive reinforcement layer 11 is sprayed on the outer surface of the insulating leveling bottom layer 10 with a thickness of 1.3 mm. The layer contains graphene filler. The sheet barrier structure formed by graphene blocks sulfuric acid molecules and pentavalent vanadium ions in the electrolyte of vanadium redox flow battery outside the coating. The semi-conductive detection layer 12 refers to the outermost structure of the three-layer composite coating 5 on the inner wall. It is set on the outer surface of the conductive reinforcement layer 11, contains conductive filler and has semi-conductivity, and is used to directly contact the electrolyte and act as a smart sensing layer to sense the health status of the coating. For example, in the underground energy storage project of vanadium redox flow battery in location A, the semi-conductive detection layer 12 is sprayed on the outer surface of the conductive reinforcement layer 11 with a thickness of 0.5 mm, and the layer is in direct contact with the electrolyte of vanadium redox flow battery.

[0037] The insulating leveling bottom layer 10 is an insulating coating without conductive filler, the conductive reinforcing layer 11 is a conductive coating containing conductive filler, and the semi-conductive detection surface layer 12 is a semi-conductive coating containing conductive filler.

[0038] The insulating coating refers to a coating without conductive fillers, possessing high volume resistivity, used to block current conduction paths; for example, in the vanadium redox flow battery underground energy storage project at location A, the insulating leveling layer 10 is the insulating coating, with a volume resistivity greater than 10. 12 Ω·cm, electrically isolating the conductive reinforcement layer 11 from the steel reinforcement in the concrete structure layer of the chamber.

[0039] The conductive filler refers to a filler material added to the coating to impart conductivity to it. For example, in the vanadium redox flow battery underground energy storage project at location A, 0.8% by mass of surface-modified graphene is added to the conductive reinforcement layer 11 as a conductive filler, resulting in a volume resistivity of 10⁻⁶. 3 Ω·cm~10 6Ω·cm. A conductive coating refers to a coating containing conductive fillers and possessing conductive properties; for example, in the vanadium redox flow battery underground energy storage project at location A, the conductive reinforcement layer 11 is a conductive coating with a volume resistivity of 10 Ω·cm. 5 Ω·cm. A semi-conductive coating refers to a coating containing conductive fillers and possessing semi-conductive properties, with a volume resistivity between that of an insulator and a conductor. For example, in the vanadium redox flow battery underground energy storage project at location A, the semi-conductive detection surface layer 12 is a semi-conductive coating with a volume resistivity of 10 Ω·cm. 8 Ω·cm.

[0040] An embedded electrode array 13 is provided between the semiconductive detection surface layer 12 and the conductive reinforcement layer 11. The embedded electrode array 13 is led out to the ground data acquisition box through a corrosion-resistant wire.

[0041] The pre-embedded electrode array 13 refers to an array structure composed of multiple electrodes pre-embedded at the interface between the semi-conductive detection surface layer 12 and the conductive reinforcement layer 11, used to collect resistance value signals in various areas of the coating. For example, in the underground energy storage project of vanadium redox flow battery in location A, the pre-embedded electrode array 13 consists of 36 flexible electrodes arranged at equal intervals in a grid structure of 6 rows by 6 columns, with a spacing of 1.0m between each electrode, and the electrode material is the same as that of the semi-conductive detection surface layer 12.

[0042] The corrosion-resistant wire refers to a wire with resistance to electrolyte corrosion, used to lead the electrical signals of each electrode in the pre-embedded electrode array 13 to the ground data acquisition box. For example, in the vanadium redox flow battery underground energy storage project at location A, each electrode is connected to a corrosion-resistant wire, and all 36 wires are led out from inside the chamber and connected to the ground data acquisition box. The ground data acquisition box refers to a data acquisition device installed on the ground, with a built-in microprocessor and wireless transmission module, used to receive the resistance value signals transmitted by the pre-embedded electrode array 13 and perform data processing. For example, in the vanadium redox flow battery underground energy storage project at location A, the ground data acquisition box is installed in the ground equipment room next to the chamber entrance, with a built-in microprocessor for calculating the resistance change rate between each electrode and a built-in wireless transmission module for sending alarm signals to the ground monitoring center.

[0043] The ground data acquisition box has a built-in microprocessor and a wireless transmission module. The microprocessor is used to locate the damaged area of ​​the inner wall three-layer composite coating 5 according to the resistance value change between each electrode in the pre-embedded electrode array 13. The wireless transmission module is used to send the information of the damaged area to the ground monitoring center.

[0044] The resistance change refers to the change in the resistance between each electrode in the pre-embedded electrode array 13 relative to the initial resistance value. For example, in the vanadium redox flow battery underground energy storage project at location A, when the semiconductive detection surface layer 12 is intact, the resistance between any two electrodes remains stable at 10. 8 Ω·cm (this value is within the volume resistivity range of 10 for the semiconductive detection surface layer 12) 6 Ω·cm to 10 9 Within Ω·cm, when the coating is damaged and electrolyte seeps in, the resistance between the two electrodes near the damage point drops to 8×10⁻⁶. 7 The resistance value changes by 20% (Ω·cm), triggering an alarm.

[0045] The damaged area refers to a localized area within the three-layer composite coating 5 of the inner wall that has been damaged, cracked, or peeled off, resulting in electrolyte seepage into the coating. For example, in the vanadium redox flow battery underground energy storage project at location A, a 0.4m × 0.6m damaged area at the bottom of the chamber was located by a microprocessor. Within this area, the semi-conductive detection layer 12 had lost its integrity, and electrolyte had seeped into the surface of the conductive reinforcement layer 11. The ground monitoring center refers to a remote monitoring facility located on the ground, used to receive, display, and record information about the damaged area sent by the ground data acquisition box. For example, in the vanadium redox flow battery underground energy storage project at location A, the ground monitoring center is located in the control building of the project plant. When the wireless transmission module sends an alarm signal and the coordinates of the damaged area, the ground monitoring center displays the alarm information and records the location and time of the damaged area.

[0046] The technical solution of this embodiment solves the problems of insufficient bonding strength between the anti-corrosion coating and concrete in underground chambers, the accelerated corrosion caused by conductive filler forming a galvanic circuit with the reinforcing steel in a humid environment, the lack of deformation coordination ability of the coating, and the difficulty in real-time monitoring and location after failure by setting a three-layer composite gradient structure on the inner wall surface of the concrete structure layer of the chamber, consisting of an insulating leveling bottom layer, a conductive reinforcement layer, and a semi-conductive detection surface layer. In conjunction with the microprocessor and wireless transmission module in the ground data acquisition box, this solution solves the problems of insufficient bonding strength between the anti-corrosion coating and concrete in underground chambers, the lack of conductive filler forming a galvanic circuit with the reinforcing steel in a humid environment, the lack of deformation coordination ability of the coating, and the difficulty in real-time monitoring and location after failure. It realizes real-time perception of the health status of the coating and accurate location of the damaged area, improves the anti-corrosion reliability and operation and maintenance safety of the underground energy storage chamber of the flow battery, and reduces the repair difficulty and electrolyte leakage risk after coating failure.

[0047] In one alternative embodiment, the concrete structure layer of the chamber is located in a soil-soft rock chamber. The concrete structure layer of the chamber includes an initial support 2 and a secondary lining 3. The initial support 2 is disposed on the inner surface of the soil-soft rock surrounding rock 1 and is a combination structure of a shotcrete layer and a steel arch frame. The secondary lining 3 is a cast-in-place reinforced concrete lining disposed on the inner surface of the initial support 2. A three-layer composite coating 5 is disposed on the inner surface of the secondary lining 3. An outer waterproof and anti-corrosion layer 4 is disposed between the outer surface of the secondary lining 3 and the inner surface of the initial support 2.

[0048] Among them, the soil-soft rock chamber refers to an underground chamber excavated in soil or soft rock strata, which maintains the stability of the chamber by using a combination of initial support 2 and secondary lining 3. For example, in the underground energy storage project of vanadium redox flow battery in area A, the chamber is located in soft rock strata. The initial support 2 is a combination structure of shotcrete layer and steel arch frame, and the secondary lining 3 is a cast-in-place reinforced concrete lining. The two together constitute the concrete structural layer of the chamber.

[0049] The initial support 2 refers to the first support structure constructed immediately after the excavation of the soft rock chamber, used to promptly seal the surface of the surrounding rock and withstand the initial pressure of the surrounding rock. For example, in the vanadium redox flow battery underground energy storage project at location A, the initial support 2 is constructed immediately after the chamber excavation is completed. The initial support 2 is a combination structure of shotcrete layer and steel arch frame. The shotcrete layer covers the inner surface of the soft rock surrounding rock, and the steel arch frame is erected along the longitudinal direction of the chamber at 1.0m intervals. The secondary lining 3 refers to the second lining 3 structure constructed after the initial support 2 is completed. It is a cast-in-place reinforced concrete lining, serving as the main load-bearing structure of the chamber's concrete structural layer. For example, in the vanadium redox flow battery underground energy storage project at location A, the secondary lining 3 is constructed inside the initial support 2. The secondary lining 3 is a cast-in-place reinforced concrete lining with a thickness of 350mm, and its inner wall surface is the inner wall surface of the chamber's concrete structural layer.

[0050] The shotcrete layer refers to a concrete layer constructed using the spraying method, used to seal the surface of the surrounding rock and provide support resistance. For example, in the vanadium redox flow battery underground energy storage project at location A, the shotcrete layer in the initial support 2 is 150mm thick, covering the inner surface of the soft surrounding rock, and a steel arch frame is installed inside the shotcrete layer. The steel arch frame refers to an arched support frame made of steel profiles, installed inside the shotcrete layer to improve the load-bearing capacity of the initial support 2. For example, in the vanadium redox flow battery underground energy storage project at location A, the steel arch frame is made of I-beams and erected along the longitudinal direction of the chamber at 1.0m intervals inside the shotcrete layer.

[0051] Among them, cast-in-place reinforced concrete lining refers to a reinforced concrete lining structure constructed using the formwork casting method, which serves as the secondary lining 3 of the chamber. For example, in the underground energy storage project of vanadium redox flow battery in area A, the cast-in-place reinforced concrete lining is constructed using the formwork casting method on the inner side of the initial support 2, with a thickness of 350mm, a concrete strength grade of C40, and internal steel mesh.

[0052] In the above-mentioned optional methods, further considering the geological characteristics of soil and soft rock chambers, a layered bearing system is formed by initial support and secondary lining. The outer wall waterproof and anti-corrosion layer is set between the outer surface of the secondary lining and the initial support, so that the inner wall three-layer composite coating and the outer wall waterproof and anti-corrosion layer act on different structural layers respectively, achieving internal and external layered protection and adapting to the deformation requirements of soft rock strata.

[0053] In one alternative embodiment, the concrete structure layer of the chamber is located in a hard rock chamber. The concrete structure layer of the chamber is a shotcrete and anchor support structure 7, which is disposed on the inner surface of the hard rock surrounding rock 6. The shotcrete and anchor support structure 7 is a combination structure of shotcrete layer and system anchor bolts. The inner wall three-layer composite coating 5 is disposed on the inner wall surface of the shotcrete and anchor support structure 7. The outer wall waterproof and anti-corrosion layer 4 is a partial outer wall waterproof and anti-corrosion layer 8, which is disposed between the outer surface of the shotcrete and anchor support structure 7 and the inner surface of the hard rock surrounding rock 6 and is only disposed in the groundwater development section.

[0054] The term "hard rock chamber" refers to an underground chamber excavated in hard rock strata, where a shotcrete and anchor support structure 7 serves as the concrete structural layer. For example, in the vanadium redox flow battery underground energy storage project at location A, the chamber is located in granite strata. After excavation, the shotcrete and anchor support structure 7 is directly constructed as the concrete structural layer, eliminating the need for secondary lining 3. The shotcrete and anchor support structure 7 refers to a support structure composed of a shotcrete layer and system anchor bolts, serving as the concrete structural layer of the hard rock chamber. For example, in the vanadium redox flow battery underground energy storage project at location A, the shotcrete layer in the shotcrete and anchor support structure 7 is 120mm thick, covering the inner surface of the hard rock surrounding rock 6. The system anchor bolts are arranged at 1.5m × 1.5m intervals, with a length of 3.0m.

[0055] The "partial external waterproof and anti-corrosion layer 8" refers to the external waterproof and anti-corrosion layer 4 installed only in the groundwater-developed section of the hard rock chamber, used to locally prevent groundwater from seeping into the sprayed anchor support structure 7. For example, in the vanadium redox flow battery underground energy storage project at location A, there is a 20m long groundwater-developed section at the top of the hard rock chamber. A partial external waterproof and anti-corrosion layer 8 is installed between the outer surface of the sprayed anchor support structure 7 and the inner surface of the hard rock surrounding rock 6 in this section, covering only the 20m section. The groundwater-developed section refers to a geological section in the surrounding rock of the underground chamber where groundwater seepage is active and the water volume is large. For example, in the vanadium redox flow battery underground energy storage project at location A, there is a 20m long section at the top of the hard rock chamber where rock fissures are developed and the groundwater seepage rate reaches 5m³ / day. 3 The section was identified as a groundwater-developed section.

[0056] Among the above-mentioned optional methods, for the surrounding rock conditions of hard rock chambers, a shotcrete and anchor support structure is adopted as the concrete structural layer, and the outer wall waterproof and anti-corrosion layer is only set in the groundwater development section, avoiding unnecessary construction in dry rock areas. While reducing material usage and construction costs, the waterproof and anti-corrosion effect of key seepage points is guaranteed.

[0057] In one alternative embodiment, the insulating leveling substrate 10 is made of silicone-modified epoxy resin or phenolic epoxy resin, and the insulating leveling substrate 10 contains insulating filler. The insulating leveling substrate 10 is used to fill micro-cracks and pores on the surface of the chamber concrete structure layer to provide a flat base surface. The insulating leveling substrate 10 is used to isolate the electrical contact between the conductive reinforcing layer 11 and the chamber concrete structure layer.

[0058] Organosilicon-modified epoxy resin refers to a resin material obtained by chemically modifying epoxy resin with organosilicon compounds, exhibiting excellent bonding performance and flexibility. For example, in the underground energy storage project for vanadium redox flow batteries in location A, the material of the insulating leveling layer 10 is organosilicon-modified epoxy resin, and the bonding strength between the resin and the inner wall surface of the concrete structure layer of the chamber is 9 MPa. Phenolic epoxy resin refers to a resin material obtained by blending or copolymerizing phenolic resin and epoxy resin, exhibiting excellent chemical corrosion resistance. For example, in the underground energy storage project for vanadium redox flow batteries in location A, the material of the insulating leveling layer 10 is phenolic epoxy resin, and the resin can withstand long-term immersion in the electrolyte of the vanadium redox flow battery.

[0059] The insulating filler refers to a non-conductive filler material added to the insulating coating to enhance its insulation performance. For example, in the vanadium redox flow battery underground energy storage project in location A, silica powder is added as an insulating filler to the insulating leveling layer 10, with a silica powder mass percentage of 15%. The smooth base surface refers to a smooth, flat coating surface formed after the insulating leveling layer 10 fills micro-cracks and holes, providing a uniform adhesion substrate for the conductive reinforcement layer 11. For example, in the vanadium redox flow battery underground energy storage project in location A, after the insulating leveling layer 10 is sprayed, all micro-cracks and holes on the original concrete inner wall surface are filled, forming a smooth base surface. The conductive reinforcement layer 11 is then sprayed onto the smooth base surface with uniform thickness.

[0060] In the above-mentioned optional methods, silicone-modified epoxy resin or phenolic epoxy resin is further used as the insulating leveling substrate material, and insulating filler is added. On the basis of filling the micro-cracks and holes on the concrete surface to provide a flat base surface, an electrically insulating isolation layer is formed, which blocks the electrical contact between the conductive reinforcement layer and the steel bars in the concrete structural layer and prevents the occurrence of galvanic corrosion reaction.

[0061] In one alternative embodiment, the resin matrix of the conductive reinforcing layer 11 is a phenolic epoxy vinyl ester resin, wherein a toughening modifier and surface-modified graphene filler are added to the phenolic epoxy vinyl ester resin, and the graphene filler forms a two-dimensional sheet barrier structure in the conductive reinforcing layer 11. The two-dimensional sheet barrier structure is used to block the penetration of corrosive media, and the conductive reinforcing layer 11 has flexibility to coordinate the deformation of the surrounding rock.

[0062] Among them, phenolic epoxy vinyl ester resin refers to a resin material prepared by reacting phenolic epoxy resin with vinyl ester monomer, which has low ester bond content and high crosslinking density, and excellent acid resistance and oxidation resistance. For example, in the underground energy storage project of vanadium redox flow battery in location A, the resin matrix of conductive reinforcement layer 11 is phenolic epoxy vinyl ester resin, which did not show degradation or bubbling after being soaked in 10% sulfuric acid solution for 4 months.

[0063] Among them, toughening modifier refers to an additive added to the resin matrix to improve the flexibility and elongation at break of the coating; for example, in the underground energy storage project of vanadium redox flow battery in location A, organosilicon resin is added to the phenolic epoxy vinyl ester resin of conductive reinforcement layer 11 as a toughening modifier, so that the elongation at break of conductive reinforcement layer 11 reaches 12%. Graphene filler refers to a two-dimensional sheet-like carbon material filler composed of a single layer of carbon atoms, used to improve the physical shielding performance and mechanical properties of the coating; for example, in the underground energy storage project of vanadium redox flow battery in location A, surface-modified graphene filler is added to conductive reinforcement layer 11, with a graphene mass percentage of 0.8%. The graphene sheets form a maze effect in the coating, extending the penetration path of corrosive media.

[0064] The two-dimensional sheet barrier structure refers to a barrier network formed by overlapping two-dimensional sheets of graphene filler in the coating, which is used to extend the penetration path of corrosive media. For example, in the underground energy storage project of vanadium redox flow battery in location A, the graphene filler in the conductive reinforcement layer 11 is dispersed in the resin matrix, and each graphene sheet overlaps to form a two-dimensional sheet barrier structure, which reduces the penetration rate of sulfate ions and pentavalent vanadium ions in the electrolyte of vanadium redox flow battery in the structure.

[0065] In the above-mentioned optional methods, phenolic epoxy vinyl ester resin is further used as the conductive reinforcing layer matrix, combined with toughening modifier and surface-modified graphene filler, so that graphene forms a two-dimensional sheet barrier structure in the layer, which prolongs the penetration path of corrosive media, while giving the coating flexibility to coordinate the deformation of the surrounding rock and prevent the coating from cracking and peeling off due to deformation.

[0066] In one alternative embodiment, the embedded electrode array 13 is embedded at the interface between the semiconductive detection surface layer 12 and the conductive reinforcement layer 11. The electrode material of the embedded electrode array 13 is the same as that of the semiconductive detection surface layer 12, and the embedded electrode array 13 is arranged at equal intervals.

[0067] The term "equal spacing" refers to the consistent spacing between the electrodes in the pre-embedded electrode array 13. For example, in the underground energy storage project of vanadium redox flow battery in location A, the 36 electrodes of the pre-embedded electrode array 13 are arranged in a grid of 6 rows by 6 columns with an equal spacing of 1.0m, and the spatial distance between any two adjacent electrodes is 1.0m.

[0068] In the above-mentioned optional method, the pre-embedded electrode array is further set at the interface between the semi-conductive detection surface layer and the conductive reinforcement layer. The electrode material is the same as the semi-conductive detection surface layer material and is arranged at equal intervals to ensure the consistency of electrical contact between the electrode and the detection surface layer, providing uniformly distributed sampling nodes for resistance monitoring and improving the damage location accuracy.

[0069] In one optional embodiment, the microprocessor is used to acquire the real-time resistance value between each electrode in the pre-embedded electrode array 13. The microprocessor is used to compare the real-time resistance value with the initial resistance value to obtain the resistance change rate. When the semiconductive detection surface layer 12 is damaged and electrolyte seeps in, the resistivity of the semiconductive detection surface layer 12 decreases. When the microprocessor determines that the resistance change rate exceeds a preset threshold, it generates an alarm signal. The wireless transmission module sends the alarm signal and information about the damaged area to the ground monitoring center.

[0070] The real-time resistance value refers to the resistance value measured between each electrode in the pre-embedded electrode array 13 at the current moment. For example, in the vanadium redox flow battery underground energy storage project at location A, the microprocessor in the ground data acquisition box collects the real-time resistance value between all 36 electrodes every 10 seconds. When the coating is intact, the real-time resistance value is stable at 10. 8 Ω·cm. The initial resistance value refers to the reference resistance value measured between each electrode in the pre-embedded electrode array 13 when the coating is intact and without any damage. For example, in the vanadium redox flow battery underground energy storage project in location A, before the semiconductive detection surface layer 12 is constructed and the electrolyte is injected, the microprocessor collects the resistance values ​​between all 36 electrodes as the initial resistance value, which is 10 Ω·cm. 8 Ω·cm.

[0071] The resistance change rate refers to the ratio of the change in real-time resistance value relative to the initial resistance value to the initial resistance value. For example, in the vanadium redox flow battery underground energy storage project at location A, when the coating is damaged, causing electrolyte seepage, the real-time resistance value between the two electrodes near the damage point decreases to 8 × 10⁻⁶. 7 Ω·cm, initial resistance value is 10 8 The resistance change rate is 20% (Ω·cm). The alarm signal is a signal generated when the microprocessor determines that the resistance change rate exceeds a preset threshold, indicating that the coating has been damaged. For example, in the vanadium redox flow battery underground energy storage project in location A, when the microprocessor calculates that the resistance change rate has decreased by 20%, exceeding the preset threshold of 15%, the microprocessor generates an alarm signal, which includes the location coordinates of the damaged area.

[0072] In the above-mentioned optional methods, the resistance change rate is further obtained by comparing the real-time resistance value with the initial resistance value through a microprocessor. When the semiconductive detection surface is damaged, causing electrolyte to seep in, the resistivity decreases and triggers an alarm. The alarm signal and information on the damaged area are wirelessly transmitted to the ground monitoring center to realize remote real-time monitoring of the coating health status.

[0073] In one optional approach, the preset threshold is a resistance value decrease exceeding 15%. The microprocessor uses a resistivity tomography algorithm or a localization algorithm based on the time difference of the first decrease in resistance between electrodes to calculate the location coordinates of the damaged area. The localization algorithm based on the time difference of the first decrease in resistance between electrodes is as follows: the electrolyte diffuses from the damaged point to the surrounding area, and the diffusion front passes through the areas where different electrodes are located in sequence. The resistance value of each electrode decreases in time sequence, and the absolute time of the first decrease in resistance of each electrode is recorded. The location coordinates of the leakage source are calculated based on the diffusion rate of the electrolyte in the medium and the absolute time.

[0074] Among them, the resistivity tomography algorithm refers to a localization algorithm that uses the resistance measurement values ​​between each electrode of the pre-embedded electrode array 13 to reconstruct the resistivity distribution image of the coating through inversion calculation. For example, in the underground energy storage project of vanadium redox flow battery in location A, after the microprocessor collects the resistance measurement values ​​between all 36 electrodes, the resistivity tomography algorithm is used to reconstruct the resistivity distribution image of the semiconductive detection surface layer 12, and the area with abnormally low resistivity is identified as the damaged area.

[0075] The positioning algorithm based on the time difference of the first decrease in resistance between electrodes refers to a positioning algorithm that uses the time difference of electrolyte diffusion from the damage point to different electrodes to calculate the location of the leakage source. For example, in the underground energy storage project of vanadium redox flow battery in location A, when the coating is damaged, the electrolyte diffuses from the damage point to the surrounding area. When the diffusion front passes through electrode B, the resistance of electrode B decreases for the first time. One hour later, when the diffusion front passes through electrode C, the resistance of electrode C decreases for the first time. The microprocessor records the absolute time of the first decrease in resistance of electrode B and electrode C. Based on the diffusion rate of electrolyte in the semiconductive detection surface layer 12 and the absolute time difference between the two electrodes, the coordinates of the leakage source location are calculated.

[0076] The location coordinates of the leakage source refer to the coordinates of the starting point of the electrolyte leakage from the damaged part of the inner wall three-layer composite coating 5 in the chamber space. For example, in the underground energy storage project of vanadium redox flow battery in area A, the microprocessor uses a positioning algorithm based on the time difference of the first drop in resistance between electrodes to calculate the location coordinates of the leakage source as 120m from the bottom plate of the chamber to the inlet and 3.5m from the left side wall.

[0077] In the above-mentioned optional methods, an alarm threshold is set for the resistance value drop exceeding 15%, and a resistance tomography algorithm or a positioning algorithm based on the time difference of the first drop in resistance between electrodes is used to calculate the coordinates of the leakage source by utilizing the electrolyte diffusion rate and the time difference of the first drop in resistance of each electrode, thereby improving the accuracy of the damage area positioning.

[0078] In one alternative embodiment, a detachable inspection port is provided at the pipe penetration points and valve connections of the concrete structural layer of the chamber, and a sealing flange is provided at the detachable inspection port. The surface of the sealing flange is coated with the same coating system as the three-layer composite coating of the inner wall.

[0079] Among them, the detachable inspection port refers to an inspection passage that can be opened and closed, located at the pipe penetration point and valve connection point of the concrete structure layer of the chamber. For example, in the underground energy storage project of vanadium redox flow battery in area A, a detachable inspection port with a diameter of 0.9m is set at the wall penetration point of the liquid inlet pipe of the chamber. When the three-layer composite coating 5 of the inner wall is damaged in the area, maintenance personnel open the inspection port to enter the chamber for local repair.

[0080] Among them, the sealing flange refers to the flange sealing structure installed at the detachable maintenance port, which is used to ensure the sealing performance of the chamber when the maintenance port is closed; for example, in the underground energy storage project of vanadium redox flow battery in area A, a sealing flange is installed at the detachable maintenance port, and the flange surface is coated with the same coating system as the three-layer composite coating 5 of the inner wall.

[0081] The coating system refers to a composite coating structure consisting of three layers: an insulating leveling base layer 10, a conductive reinforcement layer 11, and a semi-conductive detection surface layer 12. For example, in the underground energy storage project of vanadium redox flow battery in location A, when repairing the surface coating of the sealing flange, the same coating system as the three-layer composite coating 5 of the inner wall is adopted, that is, the insulating leveling base layer 10, the conductive reinforcement layer 11, and the semi-conductive detection surface layer 12 are applied in sequence, and the thickness of each layer is consistent with the main coating.

[0082] In the above-mentioned optional methods, a detachable inspection port is further provided at the pipe penetration point and valve connection point, and the same coating system as the three-layer composite coating of the inner wall is applied to the surface of the sealing flange, so that the inspection port area has the same anti-corrosion performance as the main coating, which facilitates local maintenance and quick replacement in the later stage and reduces the difficulty of maintenance operations.

[0083] In another embodiment of the self-sensing anti-corrosion sealing structure for the underground energy storage chamber of the flow battery of the present invention, it specifically includes: The self-sensing anti-corrosion sealing structure of the underground energy storage chamber for flow batteries incorporates a dual protection system for both inner and outer walls, specifically designed for the unique environment of underground chambers. The inner wall anti-corrosion sealing layer serves as the primary protection system, located on the inner surface of the chamber's concrete structure. This layer is a three-layer composite gradient structure, consisting of an insulating leveling layer 10, a conductive reinforcement layer 11, and a semi-conductive detection layer 12, with a total thickness controlled between 2.5mm and 3.5mm. The outer wall waterproof and anti-corrosion layer 4 serves as a redundant defense, located on the outer surface of the chamber's concrete structure. In areas with well-developed groundwater, it is partially installed. This outer wall waterproof and anti-corrosion layer 4 utilizes an organosilicon-modified waterproof and anti-corrosion coating with a thickness of 0.5mm to 1.5mm and a volume resistivity greater than [missing value]. It is used to prevent groundwater from seeping into the concrete and to block the risk of galvanic corrosion, while also serving as an emergency redundancy for inner wall protection.

[0084] Underground liquid storage offers significant advantages over surface tank solutions. Artificial chambers can provide single-tank capacities ranging from tens of thousands to hundreds of thousands of cubic meters, simplifying hundreds of tanks into one or two underground chambers, fundamentally simplifying the piping system and eliminating parallel circulation interference. At depths of 20 to 50 meters, the ground temperature remains stable at 15°C to 20°C year-round, significantly reducing temperature control energy consumption by approximately 30% to 50%, while avoiding the risks of high-temperature precipitation and low-temperature crystallization. The protective and isolation capabilities of underground spaces enable seamless construction of energy storage facilities, eliminating visual pollution and NIMBY (Not In My Backyard) effects at the source. However, underground liquid storage also presents technical challenges not present at surface solutions. Underground chambers are primarily constructed with concrete lining or shotcrete support, resulting in porous surfaces with high water content. The bonding strength between conventional anti-corrosion coatings and concrete is typically below 5 MPa, making them prone to peeling off over long-term service. Groundwater infiltration into concrete alters its ionic conductivity; if conductive fillers such as graphene are used in the anti-corrosion layer, they may form galvanic circuits with the reinforcing steel in the concrete, accelerating steel corrosion. Underground chambers, during operation, are subject to minute deformations caused by surrounding rock creep, foundation settlement, and fluctuations in gas pressure and liquid level. This necessitates that the anti-corrosion coating possess sufficient flexibility, with an elongation at break of 5% to 10% to accommodate these deformations. Limited maintenance space within the chamber makes it difficult to detect and address coating failures; therefore, real-time monitoring of the coating's health status and support for rapid, localized repairs are essential. The total acidity of the vanadium redox flow battery electrolyte is approximately 4 mol / L to 5 mol / L, and it contains highly oxidizing pentavalent vanadium ions. Conventional anti-corrosion coatings are prone to oxidative degradation and blistering under prolonged immersion, making it difficult to meet the 20- to 30-year service life requirement.

[0085] The insulating leveling layer 10 uses an organosilicon-modified epoxy resin or phenolic epoxy resin system without conductive fillers, and adds insulating fillers such as silica powder, with a volume resistivity greater than [missing value]. It has electrical insulation properties and a bonding strength with concrete or steel of not less than 8 MPa. The insulating leveling base layer 10 is used to fill micro-cracks and pores on the surface of the concrete substrate and provide a flat base surface, while completely blocking the transmission path of electrons from inside the chamber or leaked electrolyte to the concrete and steel bars, avoiding the risk of galvanic corrosion caused by groundwater infiltration.

[0086] The volume resistivity of the insulating leveling layer 10 is at least six orders of magnitude higher than that of the conductive reinforcement layer 11. This resistivity gradient ensures that even when the conductive reinforcement layer 11 and the semi-conductive detection surface layer 12 are in a conductive state, the insulating leveling layer 10 can still block the current outside the concrete structure layer of the chamber, thus preventing the graphene in the conductive reinforcement layer 11 from forming an electrochemical corrosion circuit with the steel reinforcement in the concrete.

[0087] The conductive reinforcement layer 11 uses phenolic epoxy vinyl ester resin as a matrix, and adds silicone resin toughening modifier and surface-modified graphene filler. The graphene filler accounts for 0.5% to 1.0% of the total mass of the phenolic epoxy vinyl ester resin matrix, and has a volume resistivity of [missing value]. to It possesses electrical conductivity, an elongation at break greater than 5% to 10%, and good toughness. The conductive reinforcement layer 11 utilizes the labyrinth effect of graphene sheets to form a dense physical shielding layer, blocking the penetration of corrosive media such as hydrogen ions, sulfate ions, vanadium oxide ions, and pentavalent vanadium ions, while also exhibiting resistance to strong oxidation of pentavalent vanadium. High conductivity is a structural requirement for the conductive reinforcement layer 11 to perform its shielding function. The two-dimensional sheet structure of graphene extends the penetration path of corrosive media through the labyrinth effect, and the mechanical reinforcement allows the coating to adapt to the micro-deformation of the surrounding rock.

[0088] The semiconductive detection layer 12 and the conductive reinforcement layer 11 use the same resin system, with graphene filler accounting for 0.2% to 0.5% of the total mass of the resin matrix, and a volume resistivity of [missing value]. to The semi-conductive detection layer 12 exhibits semi-conductivity and an elongation at break greater than 5% to 10%. It is abrasion-resistant, designed to withstand the erosion caused by electrolyte flow. As an integrated smart sensor, the semi-conductive detection layer 12 maintains a stable conductive network and constant resistance when the coating is intact; however, when the coating is damaged and electrolyte seeps in, the conductive network is disrupted, and the resistance drops by more than 15%. By monitoring the resistance changes of the semi-conductive detection layer 12, the health status of the coating can be inferred. The semi-conductivity ensures monitoring sensitivity without creating a strong conductive path that could pose a risk to the galvanic cell.

[0089] When the semiconductive detection layer 12 is damaged, the infiltrated electrolyte will form a low-resistance conductive path near the damage point. Experiments show that the resistivity of this area usually decreases by more than 15% after electrolyte infiltration. Therefore, setting 15% as the alarm threshold can effectively distinguish between the weak resistance fluctuations caused by normal coating aging and electrolyte leakage caused by coating damage.

[0090] An embedded electrode array 13 is disposed between the semiconductive detection surface layer 12 and the conductive reinforcement layer 11, and is embedded at the interface between the semiconductive detection surface layer 12 and the conductive reinforcement layer 11. The electrode material of the embedded electrode array 13 is the same as that of the semiconductive detection surface layer 12, and they are arranged at equal intervals, with an electrode spacing of 0.5m to 1.0m. The embedded electrode array 13 is led out to a ground data acquisition box through corrosion-resistant wires. The ground data acquisition box contains a microprocessor and a wireless transmission module. The microprocessor is used to locate the damaged area of ​​the inner wall three-layer composite coating 5 based on the resistance value changes between the electrodes in the embedded electrode array 13. When the semiconductive detection surface layer 12 is damaged and electrolyte seeps in, the seeping electrolyte will locally reduce the resistivity of the semiconductive detection surface layer 12, forming a low-resistance abnormal area. The electrolyte diffuses from the damage point outwards, and the diffusion front passes through the areas where different electrodes are located in sequence, with the resistance value between each electrode decreasing sequentially over time. By recording the absolute time of the first drop in resistance at each electrode and utilizing the diffusion rate of the electrolyte in the medium, the location of the leakage source can be calculated. The microprocessor employs a localization algorithm based on the time difference of the first drop in resistance between electrodes or a resistivity tomography algorithm, detecting damaged areas as small as 0.3m × 0.5m with a localization accuracy of ±0.5m. The wireless transmission module sends the location coordinates of the damaged area to a ground monitoring center, enabling remote real-time monitoring of the coating's health status.

[0091] To address the issue of limited maintenance space in underground chambers, this embodiment adopts a modular and maintainable design. The chamber is designed to be 100m². 2 Up to 200m 2 The system is divided into multiple independent maintenance zones, each with a relatively independent coating. Corrosion-resistant wires for the pre-embedded electrode array 13 are individually led to the ground data acquisition box. If a zone fails, only that zone needs repair, without affecting the normal operation of other zones. Removable access ports are provided at pipe penetrations and valve connections in the concrete structure layer of the chamber. These ports have a diameter of at least 0.8m to facilitate access for maintenance personnel. Sealing flanges are installed at these access ports, and their surfaces are coated with the same coating system as the three-layer composite coating 5 on the inner wall. During maintenance, the same coating system as the initial coating is used, including an insulating leveling underlayer 10, a conductive reinforcing layer 11, and a semi-conductive detection surface layer 12. After locally grinding away the failed coating, a new three-layer structure (underlayer, middle layer, and top layer) is applied. Coupling hybridization technology ensures chemical compatibility between the old and new coatings, preventing interface peeling. The maintenance area is controlled within 2m. 2 up to 5m 2 Within this timeframe, the repair cycle is 3 to 5 days, which is less than the several weeks required for a standard overall evacuation and repair plan.

[0092] Figure 2A schematic diagram of the structure of a soil-soft rock chamber is shown. In the soil-soft rock chamber, the concrete structure includes an initial support 2 and a secondary lining 3. The initial support 2 is located on the inner surface of the surrounding soil-soft rock 1 and is a combination of shotcrete and steel arches. The secondary lining 3 is a cast-in-place reinforced concrete lining located on the inner surface of the initial support 2. A three-layer composite coating 5 is applied to the inner surface of the secondary lining 3. An outer waterproof and anti-corrosion layer 4 is applied between the outer surface of the secondary lining 3 and the inner surface of the initial support 2, achieving layered protection and adapting to the deformation requirements of the soft rock strata.

[0093] Figure 3 A schematic diagram of the hard rock chamber structure is shown. In the hard rock chamber, the concrete structural layer is a shotcrete and anchor support structure 7. The shotcrete and anchor support structure 7 is installed on the inner surface of the hard rock surrounding rock 6, and is a combination of a shotcrete layer and a system of anchor bolts. A three-layer composite coating 5 is applied to the inner wall surface of the shotcrete and anchor support structure 7. The outer wall waterproof and anti-corrosion layer 4 is a partial outer wall waterproof and anti-corrosion layer 8, located between the outer surface of the shotcrete and anchor support structure 7 and the inner surface of the hard rock surrounding rock 6. This partial outer wall waterproof and anti-corrosion layer 8 is only installed in areas with well-developed groundwater to avoid unnecessary construction in dry rock areas.

[0094] Figure 4 An enlarged schematic diagram of the interlayer structure of the three-layer composite coating 5 on the inner wall is shown. An insulating leveling substrate 10 is disposed on the surface of a concrete or steel substrate 9. A conductive reinforcement layer 11 is disposed on the outer surface of the insulating leveling substrate 10. A semi-conductive detection surface layer 12 is disposed on the outer surface of the conductive reinforcement layer 11. A pre-embedded electrode array 13 is disposed at the interface between the semi-conductive detection surface layer 12 and the conductive reinforcement layer 11, ensuring consistent electrical contact between the electrodes and the detection surface layer, and providing uniformly distributed sampling nodes for resistance monitoring.

[0095] The technical solution of this embodiment will be described below through specific examples.

[0096] Example 1 is a verification of the basic coating performance. A graphene-free nano-silicate organosilicon-modified epoxy resin coating was sprayed onto the surface of a concrete sample. Tests showed that the coating's elongation at break was greater than 10%, and its bond strength to concrete was 5 MPa to 8 MPa. After 6000 hours of neutral salt spray testing with copper acceleration, the coating showed no blistering or peeling. After immersion in a 10% sulfuric acid solution for 4 months, the coating remained intact, while the concrete substrate was corroded and damaged.

[0097] Example 2 illustrates a three-layer gradient coating application scheme containing graphene, suitable for vanadium redox flow batteries. The concrete substrate of the chamber wall is ground and cleaned to remove dust and oil, ensuring a dry and smooth surface with a moisture content below 8%. An external waterproof and anti-corrosion layer 4 is sprayed or brushed onto the outer surface of the chamber's concrete structure and cured for 24 to 48 hours. A graphene-free nano-silicate coating, 1.0 mm thick, is sprayed as the insulating leveling underlayer 10 and cured for 24 hours. A graphene-modified coating, 0.5% to 1.0% graphene content, 1.2 mm thick, is sprayed onto the insulating leveling underlayer 10 as the conductive reinforcement layer 11 and cured for 24 hours. Finally, a graphene-containing coating, 0.2% to 0.5% graphene content, 0.3 mm thick, is sprayed onto the conductive reinforcement layer 11 as the semi-conductive detection surface layer 12 and cured for 24 hours. During the construction of the semi-conductive detection surface layer, a flexible electrode array is pre-embedded synchronously at 12 o'clock. The electrode spacing is 0.5m to 1.0m, and the electrode leads are led out to the ground data acquisition box. The microprocessor and wireless transmission module are debugged, and the initial resistance baseline and alarm threshold are set. The initial resistance baseline is a set value within the volume resistivity range of the semi-conductive detection surface layer, for example... An alarm is triggered when the resistance drops by more than 15%. A comprehensive acceptance inspection is conducted on the completed inner wall three-layer composite coating 5 and outer wall waterproof and anti-corrosion layer 4. The spraying process parameters are: pressure 0.4MPa to 0.7MPa, nozzle distance from the substrate 200mm to 300mm, 2 to 3 coats per layer, and a single coat thickness of 0.3mm to 0.5mm. Curing conditions are: temperature 15℃ to 30℃, relative humidity less than 80%, and curing time for each layer not less than 24 hours. The spacing of the pre-embedded flexible electrode array is 0.5m to 1.0m, and the electrode material is the same system as the semi-conductive detection surface layer 12.

[0098] Example 3 illustrates the application of a three-layer gradient structure in an aqueous flow battery. Aqueous flow batteries include zinc-bromine, iron-chromium, and zinc-iron flow batteries. The electrolyte corrosivity of aqueous flow batteries is lower than that of vanadium redox flow batteries, and they do not contain strongly oxidizing pentavalent vanadium ions. For the aqueous flow battery system, the three-layer gradient coating construction scheme from Example 2 is directly adopted, without further strengthening of the middle layer ratio. When the monitoring system issues an alarm, the damaged area is determined based on the location information. Access to this area is made through a pre-set removable inspection port, and the failed coating is locally ground away. The same system coating is then reapplied according to the steps, and the monitoring system is re-tested after repair. This scheme is used to resist the acidity and salt spray corrosion of the aqueous electrolyte, meeting the long-term service requirements of underground chambers.

[0099] The technical solution of this embodiment achieves the following beneficial effects through the above-described structural design and construction method: By employing a three-layer gradient structure, multiple challenges related to bonding, insulation, heavy-duty corrosion protection, monitoring, and deformation coordination are simultaneously addressed. Furthermore, intelligent monitoring and maintainable design are integrated, upgrading the corrosion protection layer of underground chambers from a passive covering to a proactive, repairable structure. The volume resistivity of the insulating leveling layer 10 is greater than... This design completely blocks the transmission path of electrons from the interior of the chamber to the concrete and reinforcing steel, preventing the graphene conductive layer from forming a galvanic cell circuit with the reinforcing steel in a humid underground environment. The outer waterproof and anti-corrosion layer 4 further isolates groundwater, ensuring the long-term safety of the chamber structure. The semi-conductive detection surface layer 12 is used as an integrated sensor to monitor the coating's health status in real time and promptly locate damaged areas, eliminating the need for external sensors. The modular zoning design and homogeneous repair process allow for the repair of localized failures within 3 to 5 days, without the need for complete electrolyte draining. Repair costs are reduced to 10% to 20% of traditional solutions, and downtime is reduced by more than 80%. Graphene is added to the middle and surface layers to achieve toughening, resulting in an elongation at break of over 10%, which helps to mitigate minor deformations caused by surrounding rock creep and foundation settlement. The electrolyte is stored in the underground chamber, with only necessary equipment entrances and exits remaining on the surface. The total footprint is controlled to within several hundred square meters, representing only 1% to 2% of the area required for surface storage tanks, achieving seamless construction of energy storage facilities and avoiding the NIMBY (Not In My Backyard) effect. It adopts a spraying process, adapts to the complex surface of underground chambers, and is suitable for two typical geological conditions: soft rock and hard rock, without relying on a specific material formula.

[0100] Figure 5 This diagram illustrates a construction method for a self-sensing anti-corrosion sealing structure for an underground energy storage chamber of a flow battery, provided by the present invention. The method is applied to the self-sensing anti-corrosion sealing structure for an underground energy storage chamber of a flow battery provided by the present invention. Figure 5 As shown, the construction method of the self-sensing anti-corrosion sealing structure of the underground energy storage chamber for the flow battery includes the following steps: S1. Perform base surface treatment on the inner wall surface of the concrete structure layer of the chamber to remove floating dust and oil stains from the inner wall surface, so that the inner wall surface is dry and flat. S2. Construct the outer wall waterproof and anti-corrosion layer 4 on the outer surface of the concrete structure layer of the chamber; S3. The insulating leveling base layer 10, the conductive reinforcement layer 11 and the semi-conductive detection surface layer 12 are sequentially constructed on the inner wall surface of the concrete structure layer of the chamber, and each layer is cured after construction. S4. When constructing the semi-conductive detection surface layer 12, the embedded electrode array 13 is simultaneously pre-embedded, and the embedded electrode array 13 is led out to the ground data acquisition box through the corrosion-resistant wire. S5. Debug the microprocessor and the wireless transmission module, and set the initial resistance value baseline and alarm threshold; S6. Conduct an overall acceptance inspection of the completed inner wall three-layer composite coating 5 and the outer wall waterproof and anti-corrosion layer 4.

[0101] The technical solution of this embodiment follows the construction process in the following order: base surface treatment, construction of the outer wall waterproof and anti-corrosion layer, construction of the three inner wall coatings in sequence, simultaneous installation of the pre-embedded electrode array, debugging of monitoring equipment, and overall acceptance. This solves the problems of reduced coating adhesion quality and monitoring failure caused by inadequate base surface treatment, unreasonable construction sequence of each functional layer, and disconnection between the installation of monitoring elements and coating construction in the construction of anti-corrosion coatings in underground chambers. It achieves the matching between the construction steps and the functional gradient design of the anti-corrosion sealing structure, ensuring the interface bonding quality and thickness uniformity after the insulating leveling base layer, conductive reinforcement layer, and semi-conductive detection surface layer are formed in sequence. At the same time, by completing the pre-embedding of the pre-embedded electrode array and the lead-out of the wires simultaneously during the surface layer construction stage, it avoids structural damage to the formed coating caused by secondary grooving or post-embedding operations, ensuring the electrical contact stability between the electrode array and the semi-conductive detection surface layer and the reliability of monitoring data, thus improving the construction quality and long-term service performance of the anti-corrosion sealing structure of underground energy storage chambers.

[0102] The above description is merely a preferred embodiment of the present invention and an explanation of the technical principles employed. Those skilled in the art should understand that the scope of disclosure in this invention is not limited to technical solutions formed by specific combinations of the above-described technical features, but should also cover other technical solutions formed by arbitrary combinations of the above-described technical features or their equivalents without departing from the above-disclosed concept. For example, technical solutions formed by substituting the above features with (but not limited to) technical features with similar functions disclosed in this invention.

[0103] It should be noted that the terms "first," "second," etc., used in the specification and claims of this application are used to distinguish similar objects and represent a limitation on a specific order or sequence. Where appropriate, the order of use for similar objects can be interchanged so that the embodiments of this application described herein can be implemented in an order other than that shown or described.

[0104] Although embodiments of the present invention have been shown and described above, it is understood that the above embodiments are exemplary and should not be construed as limiting the present invention. Those skilled in the art can make changes, modifications, substitutions and variations to the above embodiments within the scope of the present invention.

Claims

1. A self-sensing anti-corrosion sealing structure for an underground energy storage chamber of a flow battery, characterized in that, Includes: a three-layer composite coating on the inner wall and a waterproof and anti-corrosion layer on the outer wall; The inner wall three-layer composite coating is applied to the inner wall surface of the chamber concrete structure layer; the outer wall waterproof and anti-corrosion layer is applied to the outer surface of the chamber concrete structure layer. The three-layer composite coating on the inner wall consists of an insulating leveling base layer, a conductive reinforcement layer, and a semi-conductive detection surface layer, arranged sequentially from the inner wall surface of the concrete structure layer of the chamber outwards. The insulating leveling bottom layer is an insulating coating without conductive filler, the conductive reinforcement layer is a conductive coating containing conductive filler, and the semi-conductive detection surface layer is a semi-conductive coating containing conductive filler. An embedded electrode array is provided between the semiconductive detection surface layer and the conductive reinforcement layer, and the embedded electrode array is led out to the ground data acquisition box through a corrosion-resistant wire. The ground data acquisition box has a built-in microprocessor and a wireless transmission module. The microprocessor is used to locate the damaged area of ​​the three-layer composite coating on the inner wall based on the resistance value change between each electrode in the pre-embedded electrode array. The wireless transmission module is used to send the information of the damaged area to the ground monitoring center.

2. The self-sensing anti-corrosion sealing structure for the underground energy storage chamber of a flow battery according to claim 1, characterized in that, The concrete structure layer of the chamber is located in a soil-soft rock chamber. The concrete structure layer of the chamber includes an initial support and a secondary lining. The initial support is set on the inner surface of the soil-soft rock surrounding rock and is a combination structure of shotcrete layer and steel arch frame. The secondary lining is a cast-in-place reinforced concrete lining and is set on the inner surface of the initial support. The inner wall three-layer composite coating is set on the inner wall surface of the secondary lining. The outer wall waterproof and anti-corrosion layer is set between the outer surface of the secondary lining and the inner surface of the initial support.

3. The self-sensing anti-corrosion sealing structure for the underground energy storage chamber of a flow battery according to claim 1, characterized in that, The concrete structure layer of the chamber is located in a hard rock chamber. The concrete structure layer of the chamber is a shotcrete and anchor support structure. The shotcrete and anchor support structure is set on the inner surface of the hard rock surrounding rock. The shotcrete and anchor support structure is a combination structure of shotcrete layer and system anchor bolts. The inner wall three-layer composite coating is set on the inner wall surface of the shotcrete and anchor support structure. The outer wall waterproof and anti-corrosion layer is a partial outer wall waterproof and anti-corrosion layer. The partial outer wall waterproof and anti-corrosion layer is set between the outer surface of the shotcrete and anchor support structure and the inner surface of the hard rock surrounding rock and is only set in the groundwater developed section.

4. The self-sensing anti-corrosion sealing structure for underground energy storage chambers of flow batteries according to claim 2, characterized in that, The insulating leveling underlayer is made of silicone-modified epoxy resin or phenolic epoxy resin. The insulating leveling underlayer contains insulating filler. The insulating leveling underlayer is used to fill the micro-cracks and holes on the surface of the concrete structure layer of the chamber to provide a flat base surface. The insulating leveling underlayer is used to isolate the electrical contact between the conductive reinforcement layer and the concrete structure layer of the chamber.

5. The self-sensing anti-corrosion sealing structure for underground energy storage chambers of flow batteries according to claim 3, characterized in that, The resin matrix of the conductive reinforcement layer is phenolic epoxy vinyl ester resin. Toughening modifiers and surface-modified graphene fillers are added to the phenolic epoxy vinyl ester resin. The graphene fillers form a two-dimensional sheet barrier structure in the conductive reinforcement layer. The two-dimensional sheet barrier structure is used to block the penetration of corrosive media. The conductive reinforcement layer has flexibility to coordinate the deformation of the surrounding rock.

6. The self-sensing anti-corrosion sealing structure for underground energy storage chambers of flow batteries according to claim 1, characterized in that, The embedded electrode array is disposed at the interface between the semiconductive detection surface layer and the conductive reinforcement layer. The electrode material of the embedded electrode array is the same as that of the semiconductive detection surface layer, and the embedded electrode array is arranged at equal intervals.

7. The self-sensing anti-corrosion sealing structure for underground energy storage chambers of flow batteries according to claim 6, characterized in that, The microprocessor is used to obtain the real-time resistance value between each electrode in the pre-embedded electrode array. The microprocessor is used to compare the real-time resistance value with the initial resistance value to obtain the resistance change rate. When the semiconductive detection surface is damaged and electrolyte seeps in, the resistivity of the semiconductive detection surface decreases. When the microprocessor determines that the resistance change rate exceeds a preset threshold, it generates an alarm signal. The wireless transmission module sends the alarm signal and the information of the damaged area to the ground monitoring center.

8. The self-sensing anti-corrosion sealing structure for underground energy storage chambers of flow batteries according to claim 7, characterized in that, The preset threshold is when the resistance value decreases by more than 15%. The microprocessor uses a resistance tomography algorithm or a localization algorithm based on the time difference of the first decrease in resistance between electrodes to calculate the location coordinates of the damaged area. The localization algorithm based on the time difference of the first decrease in resistance between electrodes is as follows: the electrolyte diffuses from the damaged point to the surrounding area, and the diffusion front passes through the areas where different electrodes are located in sequence. The resistance value of each electrode decreases in time sequence, and the absolute time of the first decrease in resistance of each electrode is recorded. The location coordinates of the leakage source are calculated based on the diffusion rate of the electrolyte in the medium and the absolute time.

9. The self-sensing anti-corrosion sealing structure for underground energy storage chambers of flow batteries according to claim 1, characterized in that, The pipe penetrations and valve connections in the concrete structure layer of the chamber are provided with detachable inspection ports, and the detachable inspection ports are provided with sealing flanges. The surface of the sealing flanges is coated with the same coating system as the three-layer composite coating of the inner wall.

10. A construction method for a self-sensing anti-corrosion sealing structure for an underground energy storage chamber of a flow battery, characterized in that, The method, applied to the self-sensing corrosion-resistant sealing structure of the underground energy storage chamber for flow batteries as described in any one of claims 1 to 9, comprises: The inner wall surface of the concrete structure layer of the chamber is treated to remove dust and oil stains, so that the inner wall surface is dry and flat. The outer wall waterproof and anti-corrosion layer is constructed on the outer surface of the concrete structure layer of the chamber; The insulating leveling base layer, the conductive reinforcement layer, and the semi-conductive detection surface layer are sequentially constructed on the inner wall surface of the concrete structure layer of the chamber, and each layer is cured after construction. During the construction of the semi-conductive detection surface layer, the embedded electrode array is pre-embedded simultaneously, and the embedded electrode array is led out to the ground data acquisition box through the corrosion-resistant wire; Debug the microprocessor and the wireless transmission module, and set the initial resistance baseline and alarm threshold; The three-layer composite coating on the inner wall and the waterproof and anti-corrosion layer on the outer wall, after construction, shall be subject to overall acceptance.

Images