Energy storage unit, energy storage device and energy supply and storage system

Abstract

The invention relates to the technical field of energy storage equipment, in particular to an energy storage unit, an energy storage device and an energy supply and storage system.The energy storage unit comprises a conductive structure, the conductive structure comprises a conductive layer and an insulating layer, and the insulating layer divides the conductive layer into two conductive parts; each conductive part comprises a conductive body and a GFRP (Glass Fiber Reinforced Plastic) rib material, and the GFRP rib material is configured in the conductive body; the conductive body is prepared by filling a biochar-ECC composite material with a conductive solution. The piezoelectric film is applied to the expansion joint connecting structure of the bridge floor or the road surface for energy generation, can be used for power generation and can also be used for improving the anti-seepage performance of the expansion joint connecting structure. And by combining the energy storage device, the durability and stability of the energy storage system are remarkably improved, the energy storage cost is greatly reduced, and the problems of high cost, low energy storage density and the like in the existing energy storage technology are solved.

Description

Technical Field

[0001] The present invention relates to the technical field of energy storage equipment, and in particular to an energy storage unit, an energy storage device and an energy supply and storage system. Background Art

[0002] Large-scale energy storage is an important prerequisite for the large-scale implementation of renewable energy systems. Unlike fossil fuel energy, renewable energy sources such as solar energy, wind energy and tidal energy all require supporting energy storage devices to adjust the imbalance between energy demand and energy production and achieve peak and valley regulation of energy demand. Therefore, the large-scale development from an economy based on fossil fuels to a sustainable development economy based on renewable energy depends on the research and development of highly applicable energy storage solutions.

[0003] However, according to existing energy storage research, for example, battery energy storage, supercapacitor energy storage, mechanical energy storage, electromagnetic energy storage, thermal energy storage, etc., all have corresponding defects, which seriously hinder the development of large-scale energy storage. For example, battery energy storage technology often requires the use of elements such as cobalt, lithium, nickel, and lanthanum, and these elements are all scarce mineral resources in the country, resulting in high costs for large-scale energy storage, which is not conducive to the development of large-scale energy storage. Moreover, although battery energy storage has the advantages of small size, light weight, and rechargeability, it is widely used in mobile devices, electric vehicles and other fields. However, the battery life is limited and needs to be replaced regularly. At the same time, its charging speed is relatively slow. Therefore, in order to improve the charging life and charging speed, supercapacitor energy storage came into being. However, supercapacitors still have the defect of relatively low energy storage density, which limits their application in large-scale energy storage. Other energy storage technologies often require the use of other conversion devices and storage media, resulting in an increase in energy storage costs.

[0004] Therefore, it is necessary to provide an energy storage system that can replace the original energy storage solution and is prepared using cheap and readily available materials. Summary of the invention

[0005] In order to solve the problems of high cost and low energy storage density in the existing energy storage technology, the purpose of the present invention is to provide an energy storage unit, an energy storage device and an energy supply and storage system.

[0006] The present invention utilizes GFRP reinforcement biochar-ECC composite materials to be applied to the integrated layer of the bridge deck or road surface for energy storage, which significantly improves the durability and stability of the energy storage device and greatly reduces the energy storage cost.

[0007] To achieve the above objectives, the technical solution of the present invention is as follows.

[0008] A first aspect of the present invention provides an energy storage unit, comprising: a conductive structure, comprising a conductive layer and an insulating layer, wherein the insulating layer separates the conductive layer into two conductive parts; each of the conductive parts comprises a conductive body and a GFRP reinforcement, wherein the GFRP reinforcement is arranged in the conductive body; the conductive body is prepared by filling a biochar-ECC composite material with a conductive solution, and is configured to form a conductive network path inside the conductive body, and to connect the conductive network path with the surface of the conductive body.

[0009] The present invention utilizes GFRP reinforcement to reinforce the biochar-ECC composite material to obtain a conductive structure and perform energy storage, which can significantly improve the durability and stability of the energy storage device and greatly reduce the energy storage cost, thereby solving the problems of high cost and low energy storage density in existing energy storage technologies.

[0010] The energy storage unit of the present invention not only takes into account the properties of capacitance and load bearing, but also, due to the load bearing, the microcracks in the biochar-ECC composite material will continue to expand, causing the internal conductive network structure of the biochar-ECC composite material to continue to develop, forming a larger internal surface area, thereby forming a larger capacitance and energy storage effect.

[0011] In a preferred embodiment, the conductive solution is a sodium salt solution or a potassium salt solution; the mass percentage of sodium ions or potassium ions in the conductive solution is 5% to 30%; the biochar-ECC composite material is prepared by mixing a conductive biochar material with an ECC material at a doping amount of 1wt% to 3wt%, adding water under stirring, and hydrating and solidifying; and after hydration and solidification, the conductive biochar material and the conductive solution form a conductive network path inside the biochar-ECC composite material.

[0012] In a preferred embodiment, the material of the insulating layer is polyethylene film.

[0013] In a preferred embodiment, a biochar-ECC electrode is formed on the surface of the conductive body; the biochar-ECC electrode is obtained by solidifying a biochar-ECC composite material.

[0014] A second aspect of the present invention provides an energy storage device, comprising a plurality of energy storage units arranged in an array in sequence, wherein the energy storage units are the energy storage units described in the first aspect.

[0015] In a preferred embodiment, the plurality of energy storage units are staggeredly connected by GFRP reinforcements.

[0016] The present invention applies piezoelectric film to the expansion joint connection structure of the bridge deck or road surface to generate energy, which can not only be used for power generation, but also for improving the anti-seepage performance of the expansion joint connection structure. Combined with the energy storage device, the durability and stability of the energy storage system are significantly improved, and the energy storage cost is greatly reduced, solving the problems of high cost and low energy storage density in the existing energy storage technology.

[0017] The third aspect of the present invention provides an energy supply and storage system, which is applied to an expansion joint connection structure, wherein the energy supply and storage system includes an energy generating device and an energy storage device, and both are configured in the expansion joint connection structure; the energy storage device is the energy storage device described in the second aspect; the energy generating device includes a plurality of energy generating units, and are arranged in an array in sequence; each of the energy generating units includes: a piezoelectric film structure, which is used to convert the vibration energy of the expansion joint connection structure into electrical energy; surface electrodes, which are configured on both sides of the piezoelectric film structure; a rectifying and boosting module, which is connected to the surface electrodes, and is used to convert the electrical energy output by the piezoelectric film structure into constant direct current and boost it; the rectifying and boosting module is connected to the energy storage device and is configured to charge the energy storage device.

[0018] The energy supply and storage system of the present invention is applied to the expansion joint connection structure, and the vibration energy of the expansion joint connection structure is converted into electrical energy through the piezoelectric film structure, and then transmitted to the rectification and boosting module through the surface electrodes on both sides of the piezoelectric film structure, so as to convert the electrical energy output by the piezoelectric film structure into a constant direct current and boost the voltage, and charge the energy storage device. Therefore, the energy generation device provided in the present invention can realize the conversion of the vibration energy of the expansion joint connection structure into electrical energy and store it in the energy storage device, and combine the conductive network path in the energy storage device to form a larger capacity and energy storage effect.

[0019] The present invention applies piezoelectric film to the expansion joint connection structure of the bridge deck or road surface to generate energy, which can not only be used for power generation, but also for improving the anti-seepage performance of the expansion joint connection structure. Combined with the energy storage device, the durability and stability of the energy storage system are significantly improved, and the energy storage cost is greatly reduced.

[0020] In a preferred embodiment, the piezoelectric film structure includes multiple layers of piezoelectric films connected in parallel; the surface of each layer of the piezoelectric film has a packaging layer; the material of the packaging layer is polyethylene film; the piezoelectric film is a PVDF piezoelectric film.

[0021] In a preferred embodiment, the plurality of energy generation units are respectively connected to their corresponding energy storage units.

[0022] In a preferred embodiment, the energy supply and storage system further includes an inverter module, and the output end of the energy storage device is connected to the inverter module for converting the direct current stored in the energy storage device into alternating current and outputting the alternating current.

[0023] The present invention is connected to the energy storage device through an inverter module, which is used to convert the DC power stored in the energy storage device into AC power and output it. The input voltage of the energy storage device is 36V DC power, and the inverter module is connected to the output end of the energy storage device, which can convert the 36V DC power into 220V AC power and output it.

[0024] Beneficial effects of the present invention:

[0025] 1. The present invention utilizes GFRP reinforcement to reinforce the biochar-ECC composite material to obtain a conductive structure and perform energy storage, which can significantly improve the durability and stability of the energy storage device and greatly reduce the energy storage cost, thereby solving the problems of high cost and low energy storage density in existing energy storage technologies.

[0026] 2. The energy storage unit of the present invention not only takes into account the properties of capacitance and load bearing, but also, due to the load bearing, the microcracks in the biochar-ECC composite material will continue to expand, causing the internal conductive network structure of the biochar-ECC composite material to continue to develop, forming a larger internal surface area, thereby forming a larger capacitance and energy storage effect.

[0027] 3. The energy storage device of the present invention is applied to the expansion joint connection structure. Due to its large area, it can maximize the heat dissipation area and reduce the heat caused by internal resistance. After being fully charged, it can be connected to the power grid to realize power supply of the power grid, and can also realize peak and valley regulation of wind power and solar power generation.

[0028] 4. The present invention applies piezoelectric film to the expansion joint connection structure of the bridge deck or road surface for energy generation, which can not only be used for power generation, but also for improving the anti-seepage performance of the expansion joint connection structure. Combined with the energy storage device, the durability and stability of the energy storage system are significantly improved, and the energy storage cost is greatly reduced. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] Figure 1 It is a schematic structural diagram of an energy storage unit provided in one embodiment of the present invention.

[0030] Figure 2 It is a schematic diagram of a physical cross-section of an energy storage unit provided in one embodiment of the present invention.

[0031] Figure 3 Schematic diagram of the internal conductive network of the conductive layer in one embodiment of the present invention.

[0032] Figure 4It is a schematic diagram of an energy supply and storage system provided in one embodiment of the present invention.

[0033] Figure 5 It is a structural schematic diagram of an energy supply and storage system applied to an expansion joint connection structure in one embodiment of the present invention.

[0034] Figure 6 It is a schematic diagram of the local structure of a piezoelectric film structure in an energy supply and storage system applied to an expansion joint connection structure in one embodiment of the present invention.

[0035] Figure 7 It is a module block diagram of an energy supply and storage system in one embodiment of the present invention.

[0036] Figure 8 Schematic diagram of the structure of a piezoelectric film in one embodiment of the present invention.

[0037] In the figure, 1. conductive structure; 11. conductive layer; 111. conductive body; 112. GFRP reinforcement; 113. biochar-ECC electrode; 12. insulating layer; 2. expansion joint connection structure; 3. energy generating device; 4. energy storage device; 5. piezoelectric film structure; 51. piezoelectric film; 52. packaging layer; 6. surface electrode; 7. rectifier boost module; 8. inverter module. DETAILED DESCRIPTION

[0038] In order to make the purpose, technical solution and advantages of the present invention more clearly understood, the present invention is further described in detail below in conjunction with the embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not used to limit the present invention.

[0039] Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in the field without making any creative work shall fall within the scope of protection of the present invention.

[0040] For simplicity, some numerical ranges are disclosed herein only by way of example. However, any lower limit can be combined with any other upper limit to form an unambiguous range; and any lower limit can be combined with other lower limits to form an unambiguous range, and any upper limit can be combined with any other upper limit to form an unambiguous range. In addition, although not explicitly stated, each point or single value between the range endpoints is included in the range. Therefore, each point or single value can be combined with any other point or single value as its own lower limit or upper limit, or with other lower limits or upper limits to form an unambiguous range. It should be understood that the enumeration of numerical values ​​is only for example and should not be interpreted as exhaustive.

[0041] In the description of this article, it should be noted that, unless otherwise specified, "above", "below", "≤", and "≥" all include the number itself, "at least one" means including one or more, and the "multiple" in "one or more" means two or more.

[0042] In the following embodiments, GFRP is the full name of Glass Fiber Reinforced Polymer in English and its Chinese name is Glass Fiber Reinforced Polymer.

[0043] GFRP bars are often called glass fiber bars. GFRP bars were purchased from Hebei Senren Composite Materials Co., Ltd., with diameters ranging from 16 mm to 28 mm.

[0044] The full English name of ECC is Engineered Cementitious Composite, and its Chinese name is Engineering Cement-based Composite Material.

[0045] ECC material is a high-ductility cement-based composite material with ultra-high ductility and toughness, which was purchased from Henan Aotaili New Material Technology Co., Ltd.

[0046] A first aspect of the present invention provides an energy storage unit, comprising a conductive structure 1. Figure 1 and Figure 2 The conductive structure 1 includes a conductive layer 11 and an insulating layer 12, wherein the insulating layer 12 separates the conductive layer 11 into two conductive parts; each conductive part includes a conductive body 111 and a GFRP reinforcement 112, wherein the GFRP reinforcement 112 is disposed in the conductive body 111; the conductive body 111 is prepared by filling a conductive solution in a biochar-ECC composite material.

[0047] The embodiment of the present invention utilizes GFRP reinforcement to reinforce the biochar-ECC composite material to obtain a conductive structure and perform energy storage, which can significantly improve the durability and stability of the energy storage device, and greatly reduce the energy storage cost, solving the problems of high cost and low energy storage density in existing energy storage technologies. The energy storage unit of the embodiment of the present invention can not only take into account the properties of capacitance and load bearing, but also, due to the load bearing, the microcracks in the biochar-ECC composite material will continue to expand, causing the internal conductive network structure of the biochar-ECC composite material to continue to develop, forming a larger internal surface area, thereby forming a larger capacitance and energy storage effect.

[0048] Specifically, the preparation method of the conductive body 111 is:

[0049] The biochar-ECC composite material is immersed in a conductive solution, such as a sodium chloride solution, and the conductive solution is filled in the pores of the biochar-ECC composite material.

[0050] The embodiment of the present invention is configured to form a conductive network path inside the conductive body 111 by filling the conductive solution into the biochar-ECC composite material, and can realize the conductive network path inside the conductive body 111 and the surface of the conductive body (111) to better improve the conductive performance of the conductive body 111. The GFRP reinforcement material used has the characteristics of high durability, high strength and good insulation. Therefore, using GFRP reinforcement material to reinforce the biochar-ECC composite material for energy storage can significantly improve the durability and stability of the energy storage device and greatly reduce the energy storage cost.

[0051] The embodiment of the present invention mainly uses a conductive solution to fill the biochar-ECC composite material to form a conductive body, and forms a conductive network path inside the conductive body, and the conductive network path is connected to the surface of the conductive body. At the same time, the GFRP reinforcement material is used to enhance the conductive body, thereby improving the durability and stability of the energy storage device.

[0052] like Figure 3 The energy storage unit provided by one embodiment of the present invention can not only take into account the properties of capacitance and load bearing, but also, due to the load bearing, the microcracks in the biochar-ECC composite material will continue to expand, causing the internal conductive network structure of the biochar-ECC composite material to continue to develop, forming a larger internal surface area, thereby forming a larger capacitance and energy storage effect.

[0053] In addition, the energy storage unit provided in one embodiment of the present invention can improve durability through the combination of biochar-ECC composite materials and GFRP reinforcement materials, and the service life can be basically the same as the design life of the bridge deck or road surface, reaching 50 to 100 years.

[0054] The energy storage unit provided in one embodiment of the present invention is applied to the expansion joint connection structure. Due to its large area, it can maximize the heat dissipation area and reduce the heat caused by internal resistance. After the energy is fully charged, it can be connected to the power grid to realize power supply of the power grid, and can also realize peak and valley regulation of wind power and solar power generation.

[0055] On the basis of the above-mentioned embodiment, as a more preferred embodiment, the conductive solution is a sodium salt solution or a potassium salt solution; for example, a sodium chloride solution or a potassium chloride solution. The mass percentage of the sodium ions or potassium ions in the conductive solution is 5% to 30%. For example, 5%, 6%, 8%, 10%, 12%, 14%, 16%, 18%, 20%, 22%, 24%, 26%, 28%, 30%, etc. The embodiment of the present invention does not limit the specific type of the sodium salt solution or the potassium salt solution, and a suitable conductive solution can also be selected as needed.

[0056] Based on the above embodiment, as a more preferred embodiment, the preparation method of the biochar-ECC composite material is:

[0057] Under room temperature, the conductive biochar material is mixed into the ECC material at a dosage of 1wt% to 3wt%, and water is added under stirring conditions. After hydration and solidification, a biochar-ECC composite material is prepared; and after hydration and solidification, the conductive biochar material and the conductive solution form a conductive network pathway inside the biochar-ECC composite material.

[0058] Specifically, the preparation method of the biochar-ECC composite material is:

[0059] Under room temperature of 25℃±3℃, add conductive biochar material into ECC material in an amount of 1wt% to 3wt%, stir and mix to make the color uniform, then slowly add water under stirring conditions, stir evenly, pour into a mold, vibrate to remove bubbles and make the surface smooth. After curing for 24 hours, take the test block out of the mold, and then cure it at a temperature of 20℃±3℃ and a humidity of 85% to 95% for 28 days to prepare a biochar-ECC composite material.

[0060] In the embodiment of the present invention, the ECC material is an engineering cement-based composite material available on the market. For example, the ECC material in the embodiment of the present invention is purchased from Henan Aotaili New Material Technology Co., Ltd. In the embodiment of the present invention, conductive biochar particles are added to the ECC material to form a conductive network structure inside the ECC material during the hydration and solidification process. Due to the large microscopic internal surface area, the internal conductive network area of ​​the biochar-ECC composite material after hydration is very considerable.

[0061] Specifically, the conductive biochar material is obtained by crushing the plant material, placing it in a muffle furnace, and pyrolyzing it at 400-500° C. for 4 hours. The plant material can be straw materials such as wheat straw, rice straw, and corn straw.

[0062] Based on the above embodiment, as a more preferred embodiment, the material of the insulating layer 12 is polyethylene film. The polyethylene film is a polyethylene film available on the market. For example, the polyethylene film of the embodiment of the present invention is purchased from Lichen Plastic Products Factory, Lanshan District, Linyi City, and has a thickness of about 0.2 mm.

[0063] Based on the above embodiment, as a more preferred embodiment, a biochar-ECC electrode 113 is formed on the surface of the conductive body 111. The biochar-ECC electrode 113 is obtained by solidifying the biochar-ECC composite material. The biochar-ECC electrode 113 can be connected to the conductive network path formed inside the conductive body 111.

[0064] On the basis of the above-mentioned embodiments, the second aspect of the present invention provides an energy storage device, comprising a plurality of energy storage units arranged in an array in sequence, wherein the energy storage units are the energy storage units of the first aspect.

[0065] The energy storage unit of the embodiment of the present invention can not only take into account the properties of capacitance and load bearing, but also, due to the load bearing, the micro cracks in the biochar-ECC composite material will continue to expand, causing the internal conductive network structure of the biochar-ECC composite material to continue to develop, forming a larger internal surface area, thereby forming a larger capacitance and energy storage effect. Therefore, the energy storage device of the embodiment of the present invention is applied to the expansion joint connection structure. Due to its large area, it can maximize the heat dissipation area and reduce the heat caused by internal resistance; after the electric energy is fully charged, it can be connected to the power grid to realize power supply of the power grid, and it can also realize the peak and valley regulation of wind power and solar power generation.

[0066] Based on the above implementation, as a more preferred implementation, multiple energy storage units are staggeredly connected by GFRP reinforcements 112. The energy storage device of the embodiment of the present invention is connected by GFRP reinforcements, thereby achieving synergistic performance between the energy storage units.

[0067] Based on the above implementation, Figure 4 The third aspect of the present invention provides an energy supply and storage system, which is applied to the expansion joint connection structure. The energy supply and storage system includes an energy generating device 3 and an energy storage device 4, and both are configured in the expansion joint connection structure 2; the energy storage device 4 is the energy storage device of the second aspect; the energy generating device 3 includes a plurality of energy generating units, which are arranged in an array in sequence. Each energy generating unit includes: a piezoelectric film structure 5, a surface electrode 6, and a rectifying and boosting module 7.

[0068] Specifically, the piezoelectric film structure 5 is used to convert the vibration energy of the expansion joint connection structure 2 into electrical energy; the piezoelectric film structure 5 is an existing piezoelectric film structure available on the market.

[0069] The surface electrodes 6 are arranged on both sides of the piezoelectric film structure 5; wherein, the multilayer piezoelectric film structure needs to be polarized on the upper and lower surfaces, and polarization is usually performed by a metal deposition coating method, for example, the deposition materials used are copper, tungsten copper, aluminum, silver, etc.

[0070] The rectifying and boosting module 7 is connected to the surface electrode 6 and is used to convert the electric energy output by the piezoelectric film structure 5 into a constant direct current and boost the voltage; the rectifying and boosting module 7 is connected to the energy storage device 4 and is configured to charge the energy storage device.

[0071] In the embodiment of the present invention, the energy supply and energy storage system is applied to the expansion joint connection structure, and the vibration energy of the expansion joint connection structure is converted into electrical energy through the piezoelectric film structure, and then transmitted to the rectification and boosting module through the surface electrodes on both sides of the piezoelectric film structure, so as to convert the electrical energy output by the piezoelectric film structure into a constant direct current and boost the voltage, and charge the energy storage device. Therefore, the embodiment of the present invention can realize the conversion of the vibration energy of the expansion joint connection structure into electrical energy and store it in the energy storage device through the energy generation device set, and combine with the conductive network path in the energy storage device to form a larger capacity and energy storage effect.

[0072] In the embodiment of the present invention, the rectifier and boost module 7 includes a rectifier bridge and a boost circuit. The output end of the piezoelectric film structure 5 requires a rectifier bridge to rectify the current direction, and a boost circuit is installed to boost the output voltage. The boost voltage is 36V, which can ensure safety and improve output efficiency. This is mainly because the internal resistance of the multilayer PVDF piezoelectric film is relatively high compared to the battery, so high voltage and low current can improve output efficiency. The PVDF piezoelectric film 3 provided in the embodiment of the present invention has the characteristics of high piezoelectric coefficient, good flexibility, good durability, etc.

[0073] The full English name of PVDF is Polyvinylidene Fluoride, and its Chinese name is polyvinylidene fluoride.

[0074] During the application of the energy supply and storage system provided by the embodiment of the present invention, when a vehicle passes through the bridge deck and the expansion joint connection structure, it will cause the bridge deck expansion joint connection structure to vibrate, axially deform, bend, etc., thereby causing the multi-layer PVDF piezoelectric film to generate electricity; the PVDF piezoelectric film generates electricity through a rectifier and a boost circuit to output 36V DC power; the output 36V DC power charges the energy storage device, and after charging, it passes through an inverter to form 220V AC power, which is discharged to the outside to perform work.

[0075] The energy supply and storage system provided by the embodiment of the present invention can achieve peak and valley regulation of wind power and solar power generation. For example, when the wind is strong and the sun is bright, the electricity generated by windmills and solar panels cannot be used up and can be temporarily stored in the invention, and then output when the wind is low or electricity is needed at night.

[0076] In the embodiment of the present invention, the piezoelectric film structure 5 is applied to the expansion joint connection structure of the bridge deck or road surface to generate energy, which can not only be used for power generation, but also for improving the anti-seepage performance of the expansion joint connection structure. Combined with the energy storage device, the durability and stability of the energy storage system are significantly improved, and the energy storage cost is greatly reduced.

[0077] Based on the above embodiment, as a more preferred embodiment, the piezoelectric film structure 5 includes multiple layers of piezoelectric films 51, which are connected in parallel; the surface of each layer of piezoelectric film 51 has a packaging layer 52; the material of the packaging layer 52 is polyethylene film; the piezoelectric film 51 is a PVDF piezoelectric film.

[0078] Specifically, the built-in PVDF piezoelectric film adopts a multi-layer structure, for example, 3 to 5 layers. Of course, it can also be set according to actual needs. The embodiment of the present invention does not limit the specific number of layers. The expansion joint connection structure has cracks under normal working conditions. The embodiment of the present invention significantly improves the power output of the PVDF piezoelectric film through a multi-layer structure. The multi-layer piezoelectric film 52 is installed inside the expansion joint connection structure in an embedded manner, which can generate electricity and improve the anti-seepage performance of the expansion joint connection structure.

[0079] In addition, since the internal resistance of the piezoelectric film is relatively large, the multilayer piezoelectric film is connected in parallel, which significantly increases the output current, reduces the internal resistance of the piezoelectric film, and improves the efficiency of external work.

[0080] In a preferred embodiment, multiple energy generation units are connected to their corresponding energy storage units. In this embodiment, the energy storage device is distributed in the bridge deck integration layer in a staggered manner. This arrangement can fully utilize the bridge deck area to form a larger capacity energy storage layer, and can also disperse the internal stress of the integration layer to avoid stress concentration and improve the synergy performance of the integration layer; after being fully charged, it can be connected to the power grid to realize power supply.

[0081] In a preferred embodiment, the energy supply and storage system further includes an inverter module 8, and the output end of the energy storage device 4 is connected to the inverter module 8, which is used to convert the DC power stored in the energy storage device 4 into AC power and output it. The input voltage of the energy storage device 4 is 36V DC power, and the inverter module 8 is connected to the output end of the energy storage device 4, which can convert the 36V DC power into 220V AC power and output it.

[0082] In the embodiment of the present invention, the energy storage device is connected via an inverter module to convert the DC power stored in the energy storage device into AC power and output it. The input voltage of the energy storage device is 36V DC power, and the inverter module is connected to the output end of the energy storage device, which can convert the 36V DC power into 220V AC power and output it.

[0083] In a preferred embodiment, the expansion joint connection structure is an important component of a bridge or road infrastructure. It undergoes high-frequency axial, bending, and shear deformations in a working state and has relatively rich vibration and deformation energy. The energy of the expansion joint connection structure is collected by means of an internal PVDF piezoelectric film.

[0084] In summary, the embodiments of the present invention utilize GFRP reinforcement to reinforce the biochar-ECC composite material to obtain a conductive structure and perform energy storage, which can significantly improve the durability and stability of the energy storage device and greatly reduce the energy storage cost. Moreover, the energy storage unit can not only take into account the properties of capacitance and load bearing, but also, due to the load bearing, the microcracks in the biochar-ECC composite material will continue to expand, causing the internal conductive network structure of the biochar-ECC composite material to continue to develop, forming a larger internal surface area, thereby forming a larger capacitance and energy storage effect.

[0085] The embodiment of the present invention converts the vibration energy of the expansion joint connection structure into electrical energy through a piezoelectric film structure, and then transmits it to the rectifier and boost module through the surface electrodes on both sides of the piezoelectric film structure, so as to convert the electrical energy output by the piezoelectric film structure into a constant direct current and boost it, and charge the energy storage device. Due to its large area, it can maximize the heat dissipation area and reduce the heat caused by internal resistance; after the electric energy is fully charged, it can be connected to the power grid to realize power supply of the power grid, and it can also realize the peak and valley regulation of wind power and solar power generation. In addition, the embodiment of the present invention can realize the conversion of the vibration energy of the expansion joint connection structure into electrical energy and store it in the energy storage device through the energy generating device set up, and combine with the conductive network path in the energy storage device to form a larger capacity and energy storage effect.

[0086] The above are only preferred embodiments of the present invention and are not intended to limit the present invention. Any modifications, equivalent substitutions and improvements made within the spirit and principles of the present invention should be included in the protection scope of the present invention.

Claims

1. An energy storage unit, characterized in that: include: A conductive structure (1) comprising a conductive layer (11) and an insulating layer (12), wherein the insulating layer (12) separates the conductive layer (11) into two conductive parts; Each of the conductive parts comprises a conductive body (111) and a GFRP reinforcement (112), wherein the GFRP reinforcement (112) is arranged inside the conductive body (111); The conductive body (111) is prepared by filling a biochar-ECC composite material with a conductive solution, and is configured to form a conductive network path inside the conductive body (111), and to connect the conductive network path with the surface of the conductive body (111).

2. The energy storage unit according to claim 1, characterized in that: The conductive solution is a sodium salt solution or a potassium salt solution; the mass percentage of the sodium ions or potassium ions in the conductive solution is 5% to 30%; The biochar-ECC composite material is prepared by mixing a conductive biochar material in an amount of 1wt% to 3wt% into an ECC material, adding water under stirring, and hydrating and solidifying the mixture; and after hydration and solidification, the conductive biochar material and the conductive solution form a conductive network path inside the biochar-ECC composite material.

3. The energy storage unit according to claim 1, characterized in that: The material of the insulating layer (12) is a polyethylene film.

4. The energy storage unit according to claim 1, characterized in that: A biochar-ECC electrode (113) is formed on the surface of the conductive body (111); the biochar-ECC electrode (113) is obtained by solidifying a biochar-ECC composite material.

5. An energy storage device, characterized in that: It comprises a plurality of energy storage units which are arranged in an array in sequence, and the energy storage units are the energy storage units as claimed in claim 1.

6. The energy storage device according to claim 5, characterized in that: The plurality of energy storage units are connected in an interlaced manner via GFRP reinforcements (112).

7. An energy supply and storage system, applied to an expansion joint connection structure, characterized in that: The energy supply and storage system comprises an energy generating device (3) and an energy storage device (4), and both are arranged in the expansion joint connection structure (2); the energy storage device (4) is the energy storage device according to claim 5; The energy generating device (3) comprises a plurality of energy generating units arranged in an array in sequence; each of the energy generating units comprises: A piezoelectric film structure (5) for converting the vibration energy of the expansion joint connection structure (2) into electrical energy; Surface electrodes (6) are arranged on both sides of the piezoelectric film structure (5); A rectifying and boosting module (7) is connected to the surface electrode (6) and is used to convert the electric energy output by the piezoelectric film structure (5) into constant direct current and boost the voltage; the rectifying and boosting module (7) is connected to the energy storage device (4) and is configured to charge the energy storage device.

8. The energy supply and storage system according to claim 7, characterized in that: The piezoelectric film structure (5) comprises multiple layers of piezoelectric films (51) which are connected in parallel; the surface of each layer of the piezoelectric film (51) has a packaging layer (52); the material of the packaging layer (52) is a polyethylene film; and the piezoelectric film (51) is a PVDF piezoelectric film.

9. The energy supply and storage system according to claim 7, characterized in that: The plurality of energy generating units are respectively connected to their corresponding energy storage units.

10. The energy supply and storage system according to claim 7, characterized in that: The energy supply and storage system further comprises an inverter module (8), and the output end of the energy storage device (4) is connected to the inverter module (8), which is used to convert the direct current stored in the energy storage device (4) into alternating current and output it.

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