Hydrogen storage method and hydrogen storage device

Abstract

The application provides a hydrogen storage method and a hydrogen storage device. The hydrogen storage method comprises the following steps: adding a liquid into a liquid storage layer between an inner container and an outer container, and the liquid surface is lower than a plane where a first port of a first top pipe of the inner container is located; adding hydrogen into the inner container; sealing a second port of a second top pipe of the outer container which is located outside the first top pipe, so that the inner container is located in a sealed space of the outer container, and the first top pipe, the second top pipe and the liquid storage layer are connected. Therefore, the technical scheme of the application effectively solves the problem of poor hydrogen embrittlement resistance of the container of the hydrogen storage device in the related art.

Description

Technical Field

[0001] This invention relates to the field of hydrogen storage technology, and more specifically, to a hydrogen storage method and a hydrogen storage device. Background Technology

[0002] With the promotion of hydrogen fuel cell vehicles, the construction of supporting facilities for hydrogen fuel cell vehicles is accelerating, bringing development opportunities to hydrogen refueling stations. The market demand for large-capacity hydrogen storage containers is extremely strong in the future. As of the end of December 2020, my country had built a total of 118 hydrogen refueling stations; by the end of 2021, my country had built 218 hydrogen refueling stations, an increase of 100 over the previous year, and it is expected that by 2022, my country will have built 287 hydrogen refueling stations. In the future, with the promotion of hydrogen fuel cell vehicles, the industrial chain will be driven to develop, the construction of supporting facilities for hydrogen fuel cell vehicles will accelerate, and hydrogen refueling stations will usher in development opportunities. It is expected that by 2025, there will be 1,000 hydrogen refueling stations nationwide, and by 2035, my country will have 5,000 hydrogen refueling stations. According to GB50516—2010 "Technical Specifications for Hydrogen Refueling Stations," the maximum hydrogen storage capacity of a Class III hydrogen refueling station is 1000 kg. Calculated under the conditions of 20℃ and 45 MPa storage pressure, the total hydrogen storage volume is approximately 35 m³. 3 This means that at least 35 1000L hydrogen storage containers are needed. Therefore, the market demand for large-capacity hydrogen storage containers will be extremely strong in the future.

[0003] In a hydrogen energy system, hydrogen production is fundamental, while storage and transportation are prerequisites for large-scale application. While hydrogen production technology is now quite mature, the small size of hydrogen molecules allows them to permeate through the most common tank materials, leading to consistent hydrogen loss. Furthermore, hydrogen's flammability (especially upon contact with air) poses significant safety challenges during storage and transportation, limiting its application. With increasing global emphasis on hydrogen energy development and utilization, hydrogen storage is poised to become crucial for the hydrogen energy industry. High-pressure gaseous hydrogen storage, currently the only commercially viable technology, has seen substantial development since 1970. With advancements in fiber composite materials, polymer materials, and winding equipment and technologies, high-pressure hydrogen cylinders will undoubtedly expand their application scenarios further. It is expected to maintain its dominant position in hydrogen storage technology for a considerable period. However, while the performance of gas cylinders continues to improve, further research is needed on the hydrogen embrittlement phenomenon (hydrogen embrittlement occurs when hydrogen dissolved in steel polymerizes into hydrogen molecules, causing stress concentration that exceeds the steel's strength limit, leading to the formation of fine cracks within the steel) and failure mechanisms of high-pressure hydrogen storage cylinders. Standardization of cylinder production and testing is also crucial to continuously improve the safety performance of high-pressure hydrogen storage cylinders. Therefore, seeking safe, efficient, economical, and more energy-saving hydrogen storage technologies is the main direction for the development of hydrogen energy utilization.

[0004] Hydrogen can be produced from renewable energy sources such as wind, solar, and hydropower, and is known as "green hydrogen." This not only improves the utilization rate of renewable energy but also provides hydrogen energy with zero pollution throughout its entire lifecycle. Hydrogen exists in a gaseous state and is highly reactive, making its storage a key technological bottleneck restricting the development of the hydrogen energy industry. Currently commercialized hydrogen storage methods include high-pressure hydrogen storage, liquid hydrogen storage, and metal hydride hydrogen storage. High-pressure hydrogen storage is widely used in vehicle-mounted and hydrogen refueling station scenarios due to its relatively simple technology and high storage density. However, operating under high pressure (35MPa to 70MPa) and frequent pressure changes during hydrogen charging and discharging requires sophisticated processing techniques for container materials, significantly increasing costs and increasing the risk of fatigue damage, affecting service life and posing safety hazards. Furthermore, long-term exposure to high-pressure hydrogen environments causes hydrogen embrittlement in the storage devices, leading to decreased durability, a significantly accelerated fatigue crack propagation rate, and a substantial reduction in fatigue failure resistance. As the storage pressure increases, the material's hydrogen embrittlement sensitivity increases, resulting in poor resistance to hydrogen embrittlement. Summary of the Invention

[0005] The main objective of this invention is to provide a hydrogen storage method and a hydrogen storage device to solve the problem of poor hydrogen embrittlement resistance of containers in related technologies.

[0006] To achieve the above objectives, according to one aspect of the present invention, a hydrogen storage method is provided, comprising the following steps: adding liquid into a liquid storage interlayer between an inner container and an outer container, wherein the liquid level is lower than the plane of the first opening of the first top tube of the inner container; adding hydrogen gas into the inner container; sealing the second opening of the second top tube of the outer container located outside the first top tube, so that the inner container is located within the sealed space of the outer container, thereby connecting the first top tube, the second top tube, and the liquid storage interlayer.

[0007] Further, the step of adding liquid into the liquid storage interlayer between the inner container and the outer container, and the liquid level being lower than the plane of the first opening of the first top tube of the inner container, includes: adding liquid into the liquid storage interlayer between the inner container and the outer container through an inlet branch pipe provided on the top of the outer container.

[0008] Furthermore, the step of adding liquid into the liquid storage interlayer between the inner container and the outer container, and ensuring that the liquid level is lower than the plane of the first opening of the first top tube of the inner container, further includes: detecting the liquid level height, and stopping the liquid injection when the liquid level height reaches a preset value.

[0009] According to another aspect of the present invention, a hydrogen storage device is provided, wherein the above-described hydrogen storage method is implemented by the hydrogen storage device, the hydrogen storage device comprising: an inner container, the inner container comprising an inner container body and a first top tube disposed on the top of the inner container body, the inner container body having a hydrogen storage space, and the top of the first top tube being provided with a first opening communicating with the hydrogen storage space; an outer container, enclosing the inner container, the outer container comprising an outer container body and a second top tube disposed on the top of the outer container body, a liquid storage interlayer being formed between the inner container body and the outer container body, and the top of the second top tube being provided with a second opening communicating with the first opening and the liquid storage interlayer; the second opening being higher than the first opening; and a sealing cap, closably disposed on the second opening, wherein when the sealing cap is disposed on the second opening, a sealed space is formed inside the outer container, and there is a gap between the first opening and the sealing cap.

[0010] Furthermore, the hydrogen storage device also includes a partition connecting the outer wall of the inner container and the inner wall of the outer container, the partition separating the inner container and the outer container to form a liquid storage jacket between the inner container body and the outer container body.

[0011] Furthermore, the partition includes a first partition ring sleeved on the outer side wall of the inner container body, the first partition ring having a first flow hole penetrating the upper and lower sides of the first partition ring; and / or, the partition also includes a second partition ring supported on the outer bottom wall of the inner container body, the second partition ring having a second flow hole penetrating the inner and outer sides of the second partition ring.

[0012] Furthermore, the projection of the first spacer ring onto the horizontal plane forms a first ring, and the projection of the second spacer ring onto the horizontal plane forms a second ring. The centers of the first and second rings coincide, and the outer diameter of the second ring is smaller than the inner diameter of the first ring; and / or, the cross-sectional shape of the first spacer ring perpendicular to its axial direction is a first circle, and the cross-sectional shape of the second spacer ring perpendicular to its axial direction is a second circle.

[0013] Furthermore, the wall thickness of the inner container is in the range of 1 mm to 5 mm; and / or, the distance between the inner container and the outer container is in the range of 5 mm to 10 mm.

[0014] Furthermore, the top of the outer container body is also provided with an inlet branch pipe that communicates with the liquid storage jacket. The inlet of the inlet branch pipe is higher than the first inlet. The hydrogen storage device also includes a sealing valve that can be opened and closed at the inlet of the inlet branch pipe.

[0015] Furthermore, the inlet branch pipe includes a first pipe section connected to the outer top wall of the outer container body and a second pipe section connected to and communicating with the first pipe section. The axis of the second pipe section is vertically arranged, and the axis of the second pipe section forms an obtuse angle with the axis of the first pipe section. A sealing valve is closable at the inlet of the second pipe section. And / or, the hydrogen storage device also includes a liquid detector installed inside the inner container, which is located below the sealing valve.

[0016] According to the technical solution of this invention, the hydrogen storage method includes the following steps: adding liquid into the storage jacket between the inner container and the outer container, such that the liquid level is lower than the plane of the first opening of the first top tube of the inner container. Adding hydrogen gas into the inner container. Sealing the second opening of the second top tube of the outer container, located outside the first top tube, so that the inner container is located within the sealed space of the outer container. Connecting the first top tube, the second top tube, and the storage jacket. Thus, utilizing Pascal's principle, the liquid in the storage jacket is pressurized by the hydrogen gas, and the liquid in the storage jacket transmits the hydrogen pressure to the outer wall of the inner container and the inner wall of the outer container; the liquid in the storage jacket is the medium for transmitting hydrogen pressure. The inner wall of the inner container is pressurized by the hydrogen gas, and the outer wall of the inner container is pressurized by the liquid in the storage jacket. The inner and outer walls of the inner container experience pressures in opposite directions and at similar magnitudes. Therefore, the inner container in the liquid storage jacket only bears the constant pressure difference between the liquid and hydrogen within the jacket. This constant pressure difference is determined by the depth of the liquid in the jacket, and it is much smaller than the pressure of the hydrogen entering the second top tube. Thus, the inner container experiences a relatively small pressure difference. Furthermore, because the liquid in the jacket separates the inner and outer containers, the inner container is exposed to hydrogen but not pressurized. This decouples the hydrogen exposure from the pressure of the hydrogen storage container, reducing the risk of hydrogen embrittlement and ensuring its hydrogen storage performance, thereby improving the safety of the hydrogen storage device. Additionally, the liquid in the jacket, separating the inner and outer containers, with the inner wall of the inner container in the jacket in contact with hydrogen while the inner wall of the outer container is not, enhances the hydrogen embrittlement resistance of the outer container, resulting in good overall hydrogen embrittlement resistance and reliable safety of the hydrogen storage device. Therefore, the technical solution of the present invention effectively solves the problem of poor hydrogen embrittlement resistance of containers in related technologies. Attached Figure Description

[0017] The accompanying drawings, which form part of this application, are used to provide a further understanding of the invention. The illustrative embodiments of the invention and their descriptions are used to explain the invention and do not constitute an undue limitation of the invention. In the drawings:

[0018] Figure 1 A schematic flowchart of an embodiment of the hydrogen storage method according to the present invention is shown;

[0019] Figure 2 A cross-sectional schematic diagram of an embodiment of a hydrogen storage device according to the present invention is shown;

[0020] Figure 3 It shows Figure 2 A schematic diagram of the projection of the first spacer ring of the hydrogen storage device onto a horizontal plane;

[0021] Figure 4 It shows Figure 2 A schematic diagram of the projection of the second spacer ring of the hydrogen storage device onto a horizontal plane.

[0022] The above figures include the following reference numerals:

[0023] 10. Inner container; 11. Inner container body; 111. Hydrogen storage space; 12. First top tube; 13. First inlet; 20. Outer container; 21. Outer container body; 22. Second top tube; 23. Second inlet; 24. Liquid inlet branch pipe; 241. First pipe section; 242. Second pipe section; 31. Sealing cap; 32. Sealing valve; 33. Liquid detector; 41. Liquid storage jacket; 51. Spacer; 511. First spacer ring; 512. Second spacer ring; 52. First flow hole; 53. Second flow hole. Detailed Implementation

[0024] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. The following description of at least one exemplary embodiment is merely illustrative and is in no way intended to limit the present invention or its application or use. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0025] It should be noted that the terminology used herein is for the purpose of describing particular embodiments only and is not intended to limit the exemplary embodiments according to this application. As used herein, the singular form is intended to include the plural form as well, unless the context clearly indicates otherwise. Furthermore, it should be understood that when the terms "comprising" and / or "including" are used in this specification, they indicate the presence of features, steps, operations, devices, components, and / or combinations thereof.

[0026] Unless otherwise specifically stated, the relative arrangement, numerical expressions, and values ​​of the components and steps set forth in these embodiments do not limit the scope of the invention. It should also be understood that, for ease of description, the dimensions of the various parts shown in the drawings are not drawn to actual scale. Techniques, methods, and devices known to those skilled in the art may not be discussed in detail, but where appropriate, such techniques, methods, and devices should be considered part of the specification. In all examples shown and discussed herein, any specific values ​​should be interpreted as merely exemplary and not as limitations. Therefore, other examples of exemplary embodiments may have different values. It should be noted that similar reference numerals and letters in the following figures denote similar items; therefore, once an item is defined in one figure, it need not be further discussed in subsequent figures.

[0027] like Figure 1 and Figure 2 As shown, the hydrogen storage method in this embodiment includes the following steps:

[0028] The liquid is added into the liquid storage jacket 41 between the inner container 10 and the outer container 20, and the liquid level is lower than the plane where the first opening 13 of the first top tube 12 of the inner container 10 is located.

[0029] Add hydrogen gas into the inner container 10;

[0030] The second opening 23 of the second top tube 22 located outside the first top tube 12 of the outer container 20 is sealed so that the inner container 10 is located in the sealed space of the outer container 20, and the first top tube 12, the second top tube 22 and the liquid storage jacket 41 are connected.

[0031] Applying the technical solution of this embodiment, the hydrogen storage method includes: adding liquid into the liquid storage jacket 41 between the inner container 10 and the outer container 20, such that the liquid level is lower than the plane where the first opening 13 of the first top tube 12 of the inner container 10 is located. Adding hydrogen gas into the inner container 10. Sealing the second opening 23 of the second top tube 22 of the outer container 20, located outside the first top tube 12, so that the inner container 10 is located within the sealed space of the outer container 20, connecting the first top tube 12, the second top tube 22, and the liquid storage jacket 41. Thus, utilizing Pascal's principle, the liquid in the liquid storage jacket 41 is pressurized by the hydrogen gas, and the liquid in the liquid storage jacket 41 transmits the hydrogen pressure to the outer wall of the inner container 10 and the inner wall of the outer container 20. The liquid in the liquid storage jacket 41 serves as the medium for transmitting hydrogen pressure. The inner wall of the inner container 10 located in the portion of the liquid storage jacket 41 is pressurized by the hydrogen gas, and the outer wall of the inner container 10 is pressurized by the liquid in the liquid storage jacket 41. The inner wall and outer wall of the inner container 10 experience pressures in opposite directions and at similar magnitudes. Therefore, the portion of the inner container 10 located in the liquid storage jacket 41 only bears the constant pressure difference between the liquid and hydrogen within the jacket. This constant pressure difference is determined by the depth of the liquid within the jacket and is much smaller than the pressure of the hydrogen entering the second top tube 22. The inner container 10 experiences relatively low pressure. Furthermore, because the liquid storage jacket 41 separates the inner container 10 from the outer container 20, the pressure-bearing and hydrogen-exposed portions of the inner container 10 located in the jacket 41 are separated, reducing the likelihood of hydrogen embrittlement. Hydrogen embrittlement occurs when hydrogen dissolved in steel polymerizes into hydrogen molecules, causing stress concentration that exceeds the steel's strength limit, potentially leading to the formation of fine cracks within the steel. This ensures the hydrogen storage performance of the inner container 10 and improves the safety of the hydrogen storage device. The outer container 20, located on the inner wall of the liquid storage jacket 41, does not come into contact with hydrogen gas, which helps improve the hydrogen embrittlement resistance of the outer container 20, making the overall hydrogen storage device have good hydrogen embrittlement resistance and be safe and reliable. Therefore, the technical solution of this embodiment effectively solves the problem of poor hydrogen embrittlement resistance of the container in related technologies.

[0032] In this embodiment, the step of adding liquid into the liquid storage interlayer 41 between the inner container 10 and the outer container 20 is performed before the step of adding hydrogen into the inner container 10. The liquid can first support the outer wall of the inner container 10 located in the liquid storage interlayer 41 so that it can withstand pressure in real time during the subsequent process of adding hydrogen into the inner container 10.

[0033] It should be noted that the hydrogen pressure in this embodiment is in the range of 35 MPa to 70 MPa. The inner container 10 located in the liquid storage jacket 41 is the inner container body 11 referred to below, and the outer container 20 located in the liquid storage jacket 41 is the outer container body 21 referred to below.

[0034] like Figure 1 and Figure 2 As shown, the step of adding liquid into the liquid storage jacket 41 between the inner container 10 and the outer container 20, with the liquid level below the plane of the first opening 13 of the first top tube 12 of the inner container 10, includes: adding liquid into the liquid storage jacket 41 between the inner container 10 and the outer container 20 through the liquid inlet branch pipe 24 provided on the top of the outer container 20. The liquid level in the liquid storage jacket 41 being below the first opening 13 of the first top tube 12 of the inner container 10 makes it difficult for the liquid in the liquid storage jacket 41 to enter the inner container 10 through the first opening 13 of the first top tube 12. The inlet branch pipe 24 facilitates the individual injection of liquid into the liquid storage jacket 41, and the liquid in the inlet branch pipe 24 is connected to the liquid in the liquid storage jacket 41. According to the principle of communicating vessels, when the acceleration due to gravity is not zero and its value is equal relative to all parts of the communicating vessel, the same liquid with uniform density is injected into the communicating vessel. When the liquid is stationary relative to the communicating vessel, the liquid levels in each container of the communicating vessel remain level, and the liquid level in the inlet branch pipe 24 is level with the liquid level in the second top tube 22.

[0035] like Figure 1 and Figure 2 As shown, the step of adding liquid into the liquid storage jacket 41 between the inner container 10 and the outer container 20, with the liquid level below the plane of the first opening 13 of the first top tube 12 of the inner container 10, further includes: detecting the liquid level height, and stopping the filling when the liquid level height reaches a preset value. By detecting the liquid level height, the liquid level in the second top tube 22 is kept below the plane of the first opening 13 of the first top tube 12, thereby reducing the possibility of liquid flowing into the inner container 10 from the liquid storage jacket 41. The filling stops when the liquid level height reaches the preset value. The preset value can be the height of the first opening 13 of the first top tube 12, or it can be slightly lower than the height of the first opening 13 of the first top tube 12. Specifically, the liquid level height is detected using a liquid detector.

[0036] like Figure 2As shown, this application also provides a hydrogen storage device. The above-mentioned hydrogen storage method is implemented through the hydrogen storage device, which includes: an inner container 10, an outer container 20, and a sealing cap 31. The inner container 10 includes an inner container body 11 and a first top tube 12 disposed on the top of the inner container body 11. The inner container body 11 has a hydrogen storage space 111 inside. The top of the first top tube 12 is provided with a first opening 13 communicating with the hydrogen storage space 111. The outer container 20 is wrapped around the inner container 10. The outer container 20 includes an outer container body 21 and a second top tube 22 disposed on the top of the outer container body 21. A liquid storage interlayer 41 is formed between the inner container body 11 and the outer container body 21. The top of the second top tube 22 is provided with a second opening 23 communicating with the first opening 13 and the liquid storage interlayer 41. The second opening 23 is higher than the first opening 13. A sealing cap 31 is closable and can be placed over the second opening 23. When the sealing cap 31 is placed over the second opening 23, a sealed space is formed inside the outer container 20, and there is a gap between the first opening 13 and the sealing cap 31. Since the above-described hydrogen storage method can solve the problem of poor hydrogen embrittlement resistance of containers in related technologies, the technical solution implemented through a hydrogen storage device can also solve the same technical problem. Of course, the above-described hydrogen storage device can also be implemented independently without relying on the above-described hydrogen storage method. The above-described liquid storage jacket 41 is used to hold liquid. After the liquid storage jacket 41 holds liquid, the inner container body 11 and the first top tube 12 are used to store hydrogen gas. Hydrogen gas is introduced into the hydrogen storage device through the second port 23 of the outer container 20. Since the first port 13, the second port 23, and the liquid storage jacket 41 are connected, the hydrogen gas entering from the second port 23 of the outer container 20 applies pressure to the liquid in the liquid storage jacket 41, and the hydrogen gas can smoothly enter the inner container 10 from the first port 13. Opening the sealing cap 31 allows hydrogen gas to be introduced into the first port 13 through the second port 23, and conversely, hydrogen gas is released through both the first port 13 and the second port 23. The sealing cap 31 seals the second port 23 of the second top tube 22 of the outer container 20, so that the inner container 10 is located within the sealed space of the outer container 20. This ensures that the pressure of the hydrogen gas on the inner wall of the inner container 10 is equal to the pressure of the hydrogen gas on the liquid in the liquid storage jacket 41, and provides good sealing performance for the hydrogen storage device.

[0037] like Figure 2 As shown, the hydrogen storage device also includes a partition 51 connected to the outer wall of the inner container 10 and the inner wall of the outer container 20. The partition 51 separates the inner container 10 and the outer container 20, so that a liquid storage interlayer 41 is formed between the inner container body 11 and the outer container body 21. The partition 51 serves to isolate the inner container 10 from the outer container 20 and support the inner container 10. The partition 51 prevents the inner container 10 from directly contacting the outer container 20, allowing the liquid storage interlayer 41 to be directly formed between the inner container 10 and the outer container 20, thus providing space for liquid storage. The partition 51 is preferably made of plastic.

[0038] Of course, in embodiments not shown in the figure, the material of the spacer can also be nylon, rubber, ABS (acrylonitrile-butadiene-propylene copolymer), which do not chemically react with the liquid in the liquid storage jacket, the inner and outer containers and hydrogen.

[0039] like Figures 2 to 4 As shown, the partition 51 includes a first partition ring 511 sleeved on the outer wall of the inner container body 11. The first partition ring 511 has a first flow hole 52 penetrating its upper and lower sides. The partition 51 also includes a second partition ring 512 supported on the outer bottom wall of the inner container body 11. The second partition ring 512 has a second flow hole 53 penetrating its inner and outer sides. The first flow hole 52 and the second flow hole 53 allow the liquid in the liquid storage jacket 41 to flow, thereby transmitting the pressure applied by hydrogen. The liquid in the liquid storage jacket 41 transmits the pressure applied by hydrogen to the outer wall of the inner container 10.

[0040] In this embodiment, the outer container body 21 does not directly contact hydrogen gas and uses a conventional high-pressure vessel. The outer container body 21 includes a cylindrical body fitted outside the inner container and upper and lower hemispherical end caps located at both ends of the cylindrical body. This significantly reduces costs, including material usage costs, material quality costs, manufacturing costs, and safety assurance measures costs. It also reduces the need for more demanding non-destructive testing of welds due to hydrogen gas contact during construction, thus lowering construction costs. The outer container 20 is a conventional high-pressure vessel, and its wall thickness is determined based on the hydrogen storage pressure level. Since the outer container does not contact hydrogen gas and only needs to withstand pressure, it can be made of high-strength steel, preferably carbon steel or stainless steel, which are pressure-bearing materials.

[0041] In this embodiment, the manufacturing process of the hydrogen storage device is as follows: Two first spacer rings 511, spaced apart along the axial direction of the first top tube 12, are fitted onto the outer wall of the integrally formed inner container 10. Two second spacer rings 512 are fixed to the outer bottom wall of the inner container body 11. The spacer rings 51 and the inner container 10 are placed on the inner bottom wall of the unwelded upper hemispherical head of the outer container body 21. The cylinder of the outer container body 21 is fitted over the first spacer rings 511. The lower end of the cylinder is welded to the lower hemispherical head, and the upper end of the cylinder is welded to the upper hemispherical head, so that the outer container 20 is wrapped around the inner container 10.

[0042] Of course, in embodiments not shown in the figures, the inner container can also be welded, and the first spacer rings spaced at intervals along the axial direction of the first top tube on the outer wall of the inner container can be one, three, four, five, or more. The second spacer rings can also be directly fixed to the inner bottom wall of the outer container body of the unwelded lower hemispherical head.

[0043] In an embodiment not shown in the figure, the partition includes a first partition ring sleeved on the outer side wall of the inner container body, the first partition ring having a first flow hole penetrating the upper and lower sides of the first partition ring; or the partition further includes a second partition ring supported on the outer bottom wall of the inner container body, the second partition ring having a second flow hole penetrating the inner and outer sides of the second partition ring.

[0044] like Figures 2 to 4 As shown, the projection of the first spacer 511 onto the horizontal plane forms a first ring, and the projection of the second spacer 512 onto the horizontal plane forms a second ring. The centers of the first and second rings coincide, and the outer diameter of the second ring is smaller than the inner diameter of the first ring. The outer diameter of the second ring is smaller than the outer diameter of the inner container 10. The second spacer 512 supports the bottom of the inner container 10, isolating the outer wall of the bottom of the inner container 10 from the inner wall of the bottom of the outer container 20. It also supports the inner container 10, fixing it inside the outer container 20, preventing direct contact between the inner and outer containers, thus forming a liquid storage jacket 41. For ease of processing and forming, the cross-sectional shape of the first spacer 511 perpendicular to its axis is a first circle, and the cross-sectional shape of the second spacer 512 perpendicular to its axis is a second circle. Furthermore, the outer surfaces of the first and second spacer 511 are smooth, facilitating welding operations. In this embodiment, the second spacer 512 consists of two concentric second rings with different diameters disposed on the outer bottom wall of the inner container 10.

[0045] Of course, in embodiments not shown in the figure, the second spacer ring can be one, three, four, five or more concentrically arranged on the outer bottom wall of the inner container.

[0046] In an embodiment not shown in the figure, the projection of the first spacer ring on the horizontal plane forms a first ring, and the projection of the second spacer ring on the horizontal plane forms a second ring. The centers of the first ring and the second ring are coincident, and the outer diameter of the second ring is smaller than the inner diameter of the first ring. Alternatively, the cross-sectional shape of the first spacer ring perpendicular to its axis is a first circle, and the cross-sectional shape of the second spacer ring perpendicular to its axis is a second circle.

[0047] like Figure 2As shown, the wall thickness of the inner container 10 is in the range of 1 mm to 5 mm; and / or, the distance between the inner container 10 and the outer container 20 is in the range of 5 mm to 10 mm. The wall thickness of the inner container 10 is preferably 1 mm, 1.5 mm, 3 mm, 3.5 mm, or 5 mm. The distance between the inner container 10 and the outer container 20 is selected as 5 mm, 6.5 mm, 8 mm, 9.5 mm, or 10 mm. The liquid in the storage jacket 41 is pressurized by hydrogen gas, and the liquid in the storage jacket 41 transmits the hydrogen pressure to the outer wall of the inner container 10 and the inner wall of the outer container 20. During hydrogen filling and discharging, the pressure on the liquid in the storage jacket 41 increases or decreases simultaneously with the hydrogen pressure, without the need for pressure control. The inner wall of the inner container 10 is pressurized by hydrogen gas, and the outer wall of the inner container 10 is pressurized by the liquid in the storage jacket 41. The inner wall and outer wall of the inner container 10 experience pressures in opposite directions and at similar magnitudes. Therefore, the main body 11 of the inner container only bears the pressure generated by the depth of the liquid within the liquid storage jacket 41. Thus, the calculation of the wall thickness of the inner container 10 only needs to consider the pressure generated by the depth of the liquid within the liquid storage jacket 41. In other words, the wall thickness of the inner container 10 is determined by the pressure generated by the liquid in the liquid storage jacket 41 at the bottom of the inner container 10, which is related to the depth and density of the liquid within the liquid storage jacket 41, specifically the height of the inner container 10, i.e., P = ρgh, where P is the liquid pressure, ρ is the liquid density, g is the acceleration due to free fall, and h is the depth of the liquid. Taking water as an example, if the inner container 10 is 10 meters high, a pressure of 1 atmosphere will be generated at the bottom of the inner container 10. Therefore, the pressure-bearing capacity of the inner container 10's wall thickness design should not be less than 1 atmosphere. Furthermore, the liquid depth of the liquid surface in the liquid storage jacket 41 is 0, so the pressure on the liquid surface of the liquid storage jacket 41 is equal to the pressure of the hydrogen gas inside the hydrogen storage container. Since the pressure difference between the inner wall and the outer wall of the inner container is the pressure of the liquid in the liquid storage jacket 41 due to its depth, which is much smaller than the pressure of the hydrogen gas inside the hydrogen storage container, the inner container body 11 can be made thin-walled, resulting in a large effective hydrogen storage volume, good resistance to hydrogen embrittlement, and safety and reliability. It can realize large-scale, high-capacity hydrogen storage and is mainly used in fixed high-pressure hydrogen storage sites, such as hydrogen refueling stations and power generation hydrogen production stations.

[0048] In this embodiment, the first opening 13 of the inner container 10 is open and is a thin-walled, large-capacity gas cylinder for storing more hydrogen. The inner container 10 is made of a material with good hydrogen compatibility, which is not prone to hydrogen embrittlement. Preferably, it is made of austenitic stainless steel, high-density polyethylene, or high-strength nylon, which are polymer-based composite materials. The liquid medium stored in the liquid storage jacket 41 should not corrode the inner container 10 and the outer container 20, should not react with hydrogen, and should not volatilize, such as water or hydraulic oil.

[0049] The inventors discovered that if nitrogen is filled into the liquid storage jacket 41 as a gas to balance the hydrogen pressure in the inner container 10, the liquid storage jacket 41 and the inner container 10 need to be sealed and isolated. However, compared to liquids such as water and hydraulic oil, nitrogen has a lower pressure-bearing capacity, making it difficult to adjust the balancing gas. Pressurizing nitrogen requires the installation of a pressure regulating device and additional sealing, resulting in higher costs and more complex operation.

[0050] To address the aforementioned issues, the first top tube 12, the second top tube 22, and the liquid storage jacket 41 are connected. The liquid within the liquid storage jacket 41 is pressurized by hydrogen gas, and this pressure is transmitted to the outer wall of the inner container 10 and the inner wall of the outer container 20. When the sealing cap 31 is opened, during the hydrogen filling and discharging process through the second port 23, the pressure on the liquid within the liquid storage jacket 41 increases or decreases simultaneously with the hydrogen pressure. This eliminates the need for an additional pressure control system to manage the pressure of the jacket medium, thus reducing costs. The hydrogen filling and discharging process can directly utilize existing technologies, making it simple and easy to use.

[0051] like Figure 2 As shown, the top of the outer container body 21 is also provided with a liquid inlet branch pipe 24 communicating with the liquid storage jacket 41. The inlet of the liquid inlet branch pipe 24 is higher than the first opening 13. The hydrogen storage device also includes a sealing valve 32 that is openable and closable at the inlet of the liquid inlet branch pipe 24. The liquid inlet branch pipe 24 allows liquid to be injected into the liquid storage jacket 41. When adding liquid into the liquid storage jacket 41, the liquid in the liquid storage jacket 41 is slightly lower than or level with the plane where the first opening 13 of the first top tube 12 of the inner container 10 is located, making it difficult for the liquid in the liquid storage jacket 41 to flow into the inner container 10, and allowing the outer wall of the first top tube 12 of the inner container 10 to be subjected to the pressure of the liquid in the liquid storage jacket 41. Because the inner wall of the first top tube 12 of the inner container 10 is subjected to hydrogen pressure, the pressure on the inner wall and the outer wall of the first top tube 12 of the inner container 10 is in opposite directions but similar in magnitude. Therefore, most of the pressure on the first top tube 12 of the inner container 10 is generated only by the depth of the liquid in the liquid storage jacket 41. The inlet of the liquid inlet branch pipe 24 is higher than the first inlet 13 to facilitate the detection of the liquid in the liquid storage jacket 41. The sealing valve 32 at the inlet of the liquid inlet branch pipe 24 seals the hydrogen storage device, forming a closed space inside the hydrogen storage device.

[0052] like Figure 2As shown, the inlet branch pipe 24 includes a first pipe section 241 connected to the outer top wall of the outer container body 21 and a second pipe section 242 connected to and communicating with the first pipe section 241. The axis of the second pipe section 242 is vertically arranged, and the axis of the second pipe section 242 forms an obtuse angle with the axis of the first pipe section 241. The outer top wall of the outer container body 21 is the outer top wall of an upper hemispherical head. The axis of the second pipe section 242 forms an obtuse angle with the axis of the first pipe section 241. The axis of the first pipe section 241 is perpendicular to the tangent of the outer top wall of the upper hemispherical head, which facilitates welding the inlet branch pipe 24 to the outer top wall of the upper hemispherical head. A sealing valve 32 is closable at the inlet of the second pipe section 242 to seal the hydrogen storage device and form a closed space inside the outer container 20. The hydrogen storage device also includes a liquid detector 33 installed inside the inner container 10, which is located below the sealing valve 32. The liquid detector 33 can detect the liquid level in the storage jacket 41. Before the hydrogen storage device is put into use, liquid is added to the storage jacket 41, and the liquid detector 33 determines whether the addition is complete. During normal use of the hydrogen storage device, the liquid detector 33 periodically checks the inner container 10 for damage. When the liquid detector 33 detects a drop in the liquid level in the storage jacket 41, the inner container 10 may have ruptured. If the inner container 10 ruptures, hydrogen gas will enter the storage jacket 41 and come into direct contact with the inner wall of the outer container 20. This will not affect use in the short term. Regularly checking the liquid level in the storage jacket 41 using the liquid detector 33 can detect damage to the inner container 10, greatly reducing the possibility of safety accidents.

[0053] In an embodiment not shown in the figure, the inlet branch pipe includes a first pipe section connected to the outer top wall of the outer container body and a second pipe section communicating with and connected to the first pipe section. The axis of the second pipe section is vertically arranged, and the axis of the second pipe section forms an obtuse angle with the axis of the first pipe section. A sealing valve is closable at the inlet of the second pipe section. Alternatively, the hydrogen storage device may also include a liquid detector disposed within the inner container, located below the sealing valve. Of course, in an embodiment not shown in the figure, the liquid detector may also be portable.

[0054] In the description of this invention, it should be understood that the orientation or positional relationship indicated by directional terms such as "front, back, up, down, left, right", "horizontal, vertical, horizontal" and "top, bottom" is generally based on the orientation or positional relationship shown in the accompanying drawings, and is only for the convenience of describing this invention and simplifying the description. Unless otherwise stated, these directional terms do not indicate or imply that the device or element referred to must have a specific orientation or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation on the scope of protection of this invention; the directional terms "inner" and "outer" refer to the inner and outer contours relative to the outline of each component itself.

[0055] For ease of description, spatial relative terms such as "above," "on top of," "on the upper surface of," "above," etc., are used herein to describe the spatial positional relationship of a device or feature as shown in the figures to other devices or features. It should be understood that spatial relative terms are intended to encompass different orientations in use or operation beyond the orientation of the device as described in the figures. For example, if the device in the figures were inverted, a device described as "above" or "on top of" other devices or structures would subsequently be positioned as "below" or "under" other devices or structures. Thus, the exemplary term "above" can include both "above" and "below." The device may also be positioned in other different ways (rotated 90 degrees or in other orientations), and the spatial relative descriptions used herein will be interpreted accordingly.

[0056] Furthermore, it should be noted that the use of terms such as "first" and "second" to define components is merely for the purpose of distinguishing the corresponding components. Unless otherwise stated, the above terms have no special meaning and therefore should not be construed as limiting the scope of protection of this invention.

[0057] The above description is merely a preferred embodiment of the present invention and is not intended to limit the invention. Various modifications and variations can be made to the present invention by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

Claims

1. A hydrogen storage device, characterized in that, The hydrogen storage device includes: The inner container (10) includes an inner container body (11) and a first top tube (12) disposed on the top of the inner container body (11). The inner container body (11) has a hydrogen storage space (111) inside, and the top of the first top tube (12) is provided with a first opening (13) communicating with the hydrogen storage space (111). An outer container (20) is wrapped around the inner container (10). The outer container (20) includes an outer container body (21) and a second top tube (22) disposed on the top of the outer container body (21). A liquid storage jacket (41) is formed between the inner container body (11) and the outer container body (21). The top of the second top tube (22) is provided with a second opening (23) that communicates with the first opening (13) and the liquid storage jacket (41). The second opening (23) is higher than the first opening (13). A sealing cap (31) is closable and can be placed on the second opening (23). When the sealing cap (31) is placed on the second opening (23), a sealed space is formed inside the outer container (20). There is a gap between the first opening (13) and the sealing cap (31). The hydrogen storage device further includes a partition (51) connected to the outer wall of the inner container (10) and the inner wall of the outer container (20), the partition (51) separating the inner container (10) and the outer container (20) to form the liquid storage interlayer (41) between the inner container body (11) and the outer container body (21). The partition (51) includes a first partition ring (511) sleeved on the outer side wall of the inner container body (11), and the first partition ring (511) is provided with a first flow hole (52) penetrating the upper and lower sides of the first partition ring (511); and / or, the partition (51) further includes a second partition ring (512) supported on the outer bottom wall of the inner container body (11), and the second partition ring (512) is provided with a second flow hole (53) penetrating the inner and outer sides of the second partition ring (512).

2. The hydrogen storage device according to claim 1, characterized in that, The projection of the first spacer (511) onto the horizontal plane forms a first ring, and the projection of the second spacer (512) onto the horizontal plane forms a second ring. The centers of the first ring and the second ring coincide, and the outer diameter of the second ring is smaller than the inner diameter of the first ring; and / or, the cross-sectional shape of the first spacer (511) perpendicular to its axial direction is a first circle, and the cross-sectional shape of the second spacer (512) perpendicular to its axial direction is a second circle.

3. The hydrogen storage device according to claim 1, characterized in that, The wall thickness of the inner container (10) is in the range of 1 mm to 5 mm; and / or the distance between the inner container (10) and the outer container (20) is in the range of 5 mm to 10 mm.

4. The hydrogen storage device according to claim 1, characterized in that, The top of the outer container body (21) is also provided with an inlet branch pipe (24) that communicates with the liquid storage jacket (41). The inlet of the inlet branch pipe (24) is higher than the first inlet (13). The hydrogen storage device also includes a sealing valve (32) that is openable and closable at the inlet of the inlet branch pipe (24).

5. The hydrogen storage device according to claim 4, characterized in that, The inlet branch pipe (24) includes a first pipe section (241) connected to the outer top wall of the outer container body (21) and a second pipe section (242) connected to and communicating with the first pipe section (241). The axis of the second pipe section (242) is set vertically, and the axis of the second pipe section (242) forms an obtuse angle with the axis of the first pipe section (241). The sealing valve (32) is set at the inlet of the second pipe section (242) in an openable and closable manner. And / or, the hydrogen storage device further includes a liquid detector (33) disposed within the inner container (10), the liquid detector (33) being disposed below the sealing valve (32).

6. A method for storing hydrogen, characterized in that, Using the hydrogen storage device according to any one of claims 1 to 5, the following steps are included: The liquid is added into the liquid storage jacket (41) between the inner container (10) and the outer container (20), and the liquid level is lower than the plane of the first opening (13) of the first top tube (12) of the inner container (10); Hydrogen gas is added into the inner container (10); The second opening (23) of the second top tube (22) located outside the first top tube (12) of the outer container (20) is sealed so that the inner container (10) is located in the sealed space of the outer container (20), and the first top tube (12), the second top tube (22) and the liquid storage jacket (41) are connected.

7. The hydrogen storage method according to claim 6, characterized in that, The step of adding liquid into the liquid storage jacket (41) between the inner container (10) and the outer container (20), and wherein the liquid level is lower than the plane of the first opening (13) of the first top tube (12) of the inner container (10), includes: The liquid is added into the liquid storage jacket (41) between the inner container (10) and the outer container (20) by means of an inlet branch pipe (24) provided on the top of the outer container (20).

8. The hydrogen storage method according to claim 6, characterized in that, The step of adding liquid into the liquid storage interlayer (41) between the inner container (10) and the outer container (20), and wherein the liquid level is lower than the plane of the first opening (13) of the first top tube (12) of the inner container (10), further includes: The liquid level is detected, and the injection is stopped when the liquid level reaches a preset value.

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