Multi-stage solid hydrogen storage system and method based on photo-thermal regulation and control and temperature difference utilization

Abstract

The invention relates to the technical field of hydrogen storage, in particular to a multistage solid hydrogen storage system and method based on photo-thermal regulation and control and temperature difference utilization, and the system comprises a photo-thermal conversion cavity, at least one part of the photo-thermal conversion cavity is a light-transmitting window, the inner surface of the photo-thermal conversion cavity is provided with a solar energy absorption coating, and the solar energy absorption coating is used for receiving and converting solar radiation energy into heat energy; and the first-stage hydrogen storage container is arranged in the photo-thermal conversion cavity so as to directly or indirectly receive heat. According to the system, free solar energy is directly used as a primary heat source in the hydrogen desorption process, and the night low-temperature environment is used as a natural cold source in the hydrogen absorption process, so that the traditional electric heating and mechanical refrigeration modes are fundamentally abandoned, the operation energy consumption is greatly reduced and even eliminated, and the energy consumption is reduced. Meanwhile, the hydrogen desorption and heat absorption process of the system is coupled with solar heating in the daytime, the hydrogen absorption and heat release process is coupled with environment cooling at night, and intelligent switching between natural heating and natural cooling is achieved.

Description

Technical Field

[0001] This invention relates to the field of hydrogen storage technology, and in particular to a multi-stage solid-state hydrogen storage system and method based on photothermal regulation and temperature difference utilization. Background Technology

[0002] Hydrogen is a crucial carrier of future clean energy, and its efficient and safe storage is key to promoting hydrogen energy applications. Solid-state hydrogen storage technology has attracted much attention due to its advantages such as high volumetric hydrogen storage density and good safety. However, this technology faces a core bottleneck in its large-scale commercial application: excessively high energy consumption.

[0003] Currently, the hydrogen absorption and desorption processes of solid-state hydrogen storage materials are highly dependent on external energy input. The hydrogen desorption reaction is an endothermic process, requiring continuous heating to sustain the reaction. In existing technologies, this heat is typically provided by electric heaters or external heat transfer fluid circulation systems. This heating method, relying on high-quality external power or complex heat transfer fluid systems, results in persistently high energy consumption for the entire hydrogen storage system, significantly increasing operating costs and severely limiting its application in remote areas or mobile scenarios without stable power grid support.

[0004] Therefore, how to fundamentally innovate the energy supply method and significantly reduce or even eliminate external energy consumption in the solid hydrogen storage process has become a core technical problem that urgently needs to be solved in this field. Summary of the Invention

[0005] In view of this, the purpose of this invention is to propose a multi-stage solid-state hydrogen storage system and method based on photothermal regulation and temperature difference utilization, so as to solve the above-mentioned technical problems.

[0006] To achieve the above objectives, the present invention provides a multi-stage solid-state hydrogen storage system that utilizes photothermal regulation and temperature difference, comprising: A photothermal conversion cavity, at least a portion of which is a light-transmitting window, has a solar energy absorption coating on its inner surface for receiving and converting solar radiation energy into heat energy; The first-stage hydrogen storage container is located inside the photothermal conversion cavity to receive heat directly or indirectly; The second-stage hydrogen storage container is located outside the photothermal conversion cavity and is connected in series with the first-stage hydrogen storage container through a pipeline, so that the hydrogen released from the first-stage hydrogen storage container can enter and heat the second-stage hydrogen storage container. The temperature difference utilization and heat dissipation subsystem is used to utilize the ambient cold source to dissipate heat during the hydrogen absorption process of the second-stage hydrogen storage container; The intelligent control system controls the flow of the pipeline based on ambient temperature and system pressure to switch between hydrogen charging and discharging modes.

[0007] As a preferred embodiment of the present invention, the system further includes a heat insulation layer disposed on the outer surface of the photothermal conversion cavity.

[0008] As a preferred embodiment of the present invention, the photothermal conversion cavity is cylindrical, the first-stage hydrogen storage container is located on its central axis, and the second-stage hydrogen storage container is arranged around the outside of the photothermal conversion cavity.

[0009] As a preferred embodiment of the present invention, the first-stage hydrogen storage container is filled with a high-temperature hydrogen storage material, and the second-stage hydrogen storage container is filled with a low-temperature hydrogen storage material.

[0010] As a preferred embodiment of the present invention, the high-temperature hydrogen storage material is a magnesium-based hydrogen storage alloy with a hydrogen release temperature higher than 250°C; the low-temperature hydrogen storage material is a rare-earth-based or titanium-iron-based hydrogen storage alloy with a hydrogen release temperature lower than 100°C.

[0011] As a preferred embodiment of the present invention, the temperature difference utilization and heat dissipation subsystem includes heat dissipation fins disposed outside the second-stage hydrogen storage container.

[0012] As a preferred embodiment of the present invention, the intelligent control system opens the hydrogen flow path from the first stage to the second stage under daylight conditions; at night or in low-temperature environments, the intelligent control system preferentially introduces hydrogen into the second stage, and opens the flow path to the first stage after the second stage is saturated.

[0013] To better address the aforementioned technical problems, the present invention also provides a hydrogen storage method based on the above system, the method comprising the following steps: Hydrogen release steps: During the day, sunlight shines through the light-transmitting window onto the absorption coating, generating heat energy to heat the first-stage hydrogen storage container and cause it to release hydrogen; the released high-temperature hydrogen gas enters the second-stage hydrogen storage container, serving as both a hydrogen source and a heat source to cause it to release hydrogen. Hydrogen absorption process: At night or when the ambient temperature is low, external hydrogen is first introduced into the second-stage hydrogen storage container, and the heat of hydrogen absorption reaction is removed by the temperature difference and heat dissipation subsystem. When the second stage is close to saturation, hydrogen is introduced into the first-stage hydrogen storage container to absorb hydrogen.

[0014] As a preferred embodiment of the present invention, the reaction heat generated when the second-stage hydrogen storage container absorbs hydrogen is dissipated through heat dissipation fins by natural convection or forced air cooling.

[0015] As a preferred embodiment of the present invention, the sensible heat of the high-temperature hydrogen gas released from the first-stage hydrogen storage container is used to heat the second-stage hydrogen storage container.

[0016] The beneficial effects of this invention are: 1. Extremely high energy efficiency and low operating cost: The system directly uses free solar energy as the primary heat source for the hydrogen release process and the low temperature environment at night as the natural cold source for the hydrogen absorption process. This fundamentally eliminates the traditional electric heating and mechanical refrigeration modes, significantly reducing or even eliminating operating energy consumption and achieving extremely low operating costs.

[0017] 2. Ingenious thermal management and simplified system structure: The system creatively couples the "hydrogen release and heat absorption" process with daytime solar heating and the "hydrogen absorption and heat release" process with nighttime environmental cooling, achieving intelligent switching between "natural heating" and "natural cooling." This not only eliminates the need for complex and energy-intensive active temperature control equipment but also greatly simplifies the system structure and improves reliability.

[0018] 3. Multi-stage synergistic effect and performance optimization: By connecting high-temperature and low-temperature hydrogen storage materials in series and optimizing their spatial layout (central high-temperature stage and surrounding low-temperature stage), the hydrogen pressure is gradually reduced and the heat is utilized in stages. The high-temperature hydrogen released in the first stage also serves as the hydrogen source and heat source for the second stage, ensuring full energy utilization, stable output pressure, and overall improvement in the system's hydrogen storage capacity and kinetic performance.

[0019] 4. Strong environmental adaptability and intelligent interaction: The system is particularly suitable for regions with significant diurnal temperature differences. It can intelligently exchange energy with the natural environment, realizing an all-weather, adaptive "light-heat-hydrogen" energy cycle, which broadens the application scenarios of solid-state hydrogen storage technology. Attached Figure Description

[0020] To more clearly illustrate the technical solutions in this invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only for this invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0021] Figure 1 This is a schematic diagram of the overall structure of the multi-stage solid-state hydrogen storage system described in this invention; Figure 2 This is a schematic diagram illustrating the working principle of the equipment in daytime hydrogen release mode. Figure 3 This is a schematic diagram illustrating the working principle of the equipment in nighttime hydrogen absorption mode.

[0022] The following are marked in the diagram: 1. Thermal insulation layer; 2. Light-transmitting window; 3. Absorbing coating; 4. First-stage hydrogen storage tank; 5. Second-stage hydrogen storage tank; 6. Heat dissipation fins; 7. Sunlight; 8. Hydrogen; 9. Hydrogen at suitable pressure; 10. External hydrogen source; 11. Cold air. Detailed Implementation

[0023] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail below with reference to specific embodiments.

[0024] It should be noted that, unless otherwise defined, the technical or scientific terms used in this invention should have the ordinary meaning understood by one of ordinary skill in the art to which this invention pertains. The terms "first," "second," and similar terms used in this invention do not indicate any order, quantity, or importance, but are merely used to distinguish different components. Terms such as "comprising" or "including" mean that the element or object preceding the word encompasses the elements or objects listed following the word and their equivalents, without excluding other elements or objects. Terms such as "connected" or "linked" are not limited to physical or mechanical connections, but can include electrical connections, whether direct or indirect. Terms such as "upper," "lower," "left," and "right" are used only to indicate relative positional relationships; when the absolute position of the described object changes, the relative positional relationship may also change accordingly.

[0025] like Figure 1 , Figure 2 and Figure 3 As shown, a multi-stage solid-state hydrogen storage system based on photothermal regulation and temperature difference utilization includes: a photothermal conversion cavity, at least a portion of which is a light-transmitting window 2, and a solar energy absorption coating 3 disposed on the inner surface of the photothermal conversion cavity for receiving and converting solar radiation energy into heat energy; a first-stage hydrogen storage container disposed inside the photothermal conversion cavity to directly or indirectly receive heat; a second-stage hydrogen storage container disposed outside the photothermal conversion cavity and connected in series with the first-stage hydrogen storage container through a pipeline, so that hydrogen gas 8 released from the first-stage hydrogen storage container can enter and heat the second-stage hydrogen storage container; a temperature difference utilization and heat dissipation subsystem for using an ambient cold source to dissipate heat during the hydrogen absorption process of the second-stage hydrogen storage container; and an intelligent control system for controlling the on / off of the pipeline according to the ambient temperature and system pressure to switch between hydrogen charging mode and hydrogen discharging mode. The above technical solution can solve the problem of high energy consumption caused by the reliance on external electric heating in traditional hydrogen storage systems. Specifically, during use, the system converts solar energy into heat energy through the light-transmitting window 2 and the absorption coating 3 of the photothermal conversion cavity, directly heating the first-stage hydrogen storage container inside and triggering its hydrogen release. The released high-temperature and high-pressure hydrogen gas 8 then flows into the external second-stage hydrogen storage container, serving as both a gas source and a heat source to trigger the second-stage hydrogen release. During hydrogen absorption, the intelligent control system switches the flow path, allowing the external hydrogen gas 8 to preferentially enter the second-stage hydrogen storage container, and utilizes the temperature difference utilization and heat dissipation subsystem to dissipate the reaction heat to the environment. It directly utilizes free solar energy to drive hydrogen release and utilizes the ambient cold source to assist in hydrogen absorption, resulting in significant energy savings.

[0026] like Figure 1As shown, in this embodiment, the system also includes a thermal insulation layer 1 disposed on the outer surface of the photothermal conversion cavity; The above technical solution can solve the problem of low thermal efficiency caused by heat dissipation to the environment. Specifically, its working principle is as follows: the thermal insulation layer 1 is wrapped around the photothermal conversion cavity. During the hydrogen release process in the daytime, it can effectively reduce the heat loss from the cavity to the outside, allowing solar energy to be more concentrated on heating the first-stage hydrogen storage container. This improves the efficiency of solar energy utilization and ensures that the first-stage hydrogen storage material can quickly reach and maintain the required hydrogen release temperature.

[0027] like Figure 1 As shown, in this embodiment, the photothermal conversion cavity is cylindrical, the first-stage hydrogen storage container is located on its central axis, and the second-stage hydrogen storage container is arranged around the outside of the photothermal conversion cavity. The above technical solution can solve the problems of uneven heat distribution and complex hydrogen and heat transfer paths between stages. Specifically, its working principle is as follows: the layout allows sunlight 7 to evenly irradiate the cylindrical cavity, and the central first-stage hydrogen storage container is evenly heated; after the released hydrogen 8 flows out from the center, it can be evenly distributed to each of the surrounding second-stage hydrogen storage containers. The system has a compact structure, reasonable heat and hydrogen flow paths, and high overall thermal management and mass transfer efficiency.

[0028] Furthermore, in this embodiment, the first-stage hydrogen storage container is filled with a high-temperature hydrogen storage material, and the second-stage hydrogen storage container is filled with a low-temperature hydrogen storage material. The above technical solution resolves the contradiction between high capacity and suitable operating temperature that cannot be achieved simultaneously with a single material. Specifically, its working principle is as follows: high-temperature materials require higher temperatures to release hydrogen and have a large capacity; low-temperature materials can rapidly absorb and release hydrogen at lower temperatures. The system utilizes the former as a high-pressure hydrogen generator and the latter as a stable pressure output and rapid response unit. Through the complementary properties of the materials, a synergistic effect is achieved in providing the system with high overall capacity, rapid kinetics, and stable output pressure.

[0029] Preferably, in this embodiment, the high-temperature hydrogen storage material is a magnesium-based hydrogen storage alloy, such as high-temperature hydrogen storage materials (e.g., MgH2, Mg2NiH4, etc.), which has a high hydrogen release temperature (typically >250℃) but a large hydrogen storage capacity; the low-temperature hydrogen storage material is a rare earth-based or titanium-iron-based hydrogen storage alloy, such as TiFeH3, LaNi5H6, V-based solid solution, etc., which can rapidly absorb and release hydrogen at near room temperature or lower temperatures (0-80℃), but has a relatively low capacity; The above technical solution addresses the lack of specific and efficient material combinations to achieve effective thermal coupling and pressure connection. Specifically, its working principle is as follows: magnesium-based alloys, under solar heating, can reach their high-temperature hydrogen release conditions, releasing a large amount of hydrogen gas; while rare-earth-based or titanium-iron-based alloys can be effectively heated by the high-temperature hydrogen gas from the preceding stage, rapidly releasing hydrogen at a lower temperature. This is a proven and preferred material pairing scheme that enables efficient utilization of heat and pressure gradients.

[0030] like Figure 1 As shown, in this embodiment, the temperature difference utilization and heat dissipation subsystem includes heat dissipation fins 6 disposed outside the second-stage hydrogen storage container; The above technical solution can solve the problem of material temperature rise, hydrogen absorption rate decrease and capacity reduction caused by the inability to dissipate the heat of hydrogen absorption reaction in time. Specifically, its working principle is as follows: when absorbing hydrogen at night, the material in the second-stage hydrogen storage container undergoes an exothermic reaction. The heat dissipation fins 6 greatly increase the contact area with the low-temperature air. The heat of reaction is quickly dissipated to the atmosphere through natural convection or forced air cooling, maintaining the second-stage hydrogen storage container to absorb hydrogen efficiently and quickly at near-ambient temperature.

[0031] like Figure 2 and Figure 3 As shown, in this embodiment, the intelligent control system includes a temperature sensor, a pressure sensor, and a control valve. Based on the light intensity, ambient temperature, and internal system pressure, it intelligently controls the opening and closing of valves between different levels of hydrogen storage units, as well as the start and stop of the cooling fan, to achieve fully automatic operation. Specifically, under daylight conditions, the intelligent control system opens the hydrogen flow path from the first stage to the second stage; at night or in low-temperature environments, the intelligent control system prioritizes the introduction of hydrogen gas into the second stage, and opens the flow path to the first stage after the second stage is saturated. The above technical solution solves the problem of the system's inability to automatically switch operating modes according to environmental conditions, requiring manual intervention. Specifically, the working principle is as follows: the intelligent control system automatically opens the corresponding valves during the day based on signals from light intensity and temperature sensors, forming a hydrogen release path from the first stage to the second stage; at night, it controls hydrogen gas to first enter the second stage, and only opens the valve leading to the first stage after its pressure rises to the set value. This achieves unattended, intelligent, and efficient operation around the clock, and ensures that the hydrogen filling process proceeds in the optimal sequence.

[0032] like Figure 2 and Figure 3As shown, in order to better solve the above-mentioned technical problems, the present invention also provides a hydrogen storage method based on the above system. The method includes the following steps: Hydrogen release step: During the day, sunlight 7 shines through the light-transmitting window 2 onto the absorption coating 3 to generate heat energy, heating the first-stage hydrogen storage container to release hydrogen; the released high-temperature hydrogen gas 8 enters the second-stage hydrogen storage container, serving as a hydrogen gas 8 source and heat source to release hydrogen; Hydrogen absorption step: At night or when the ambient temperature is low, external hydrogen gas 8 is first introduced into the second-stage hydrogen storage container, and the heat of hydrogen absorption reaction is carried away by the temperature difference and the heat dissipation subsystem. When the second stage is close to saturation, hydrogen gas 8 is introduced into the first-stage hydrogen storage container to absorb hydrogen. The above-mentioned technical solution can solve the core problem of high energy consumption in the hydrogen storage process. Specifically, its working principle is as follows: the method binds the hydrogen release process with the solar irradiation period, and uses photothermal energy to start the two-stage coordinated hydrogen release; it binds the hydrogen absorption process with the low temperature period of the environment, and uses natural cold source to dissipate heat for the two-stage sequential hydrogen absorption, forming a zero-energy cycle of "photothermal-driven hydrogen release and environmental cold-driven hydrogen absorption" that is synchronized with the natural day-night rhythm, which greatly reduces the operating cost.

[0033] like Figure 3 As shown, in this embodiment, the reaction heat generated when the second-stage hydrogen storage container absorbs hydrogen is dissipated through the heat dissipation fins 6 by natural convection or forced air cooling. The above technical solution can solve the problem of insufficient or unstable heat dissipation capacity under different environmental conditions. Specifically, its working principle is as follows: In the hydrogen absorption step, the reaction heat of the second-stage hydrogen storage container is conducted to the heat dissipation fins 6. In the low-temperature environment at night, the heat dissipation is mainly achieved through natural convection. If there is no wind or the temperature is not low enough, the fan can be activated for forced air cooling to enhance heat dissipation, ensuring that the low-temperature hydrogen absorption conditions can be effectively maintained under various nighttime environments, and guaranteeing the hydrogen absorption speed and capacity.

[0034] like Figure 2 As shown, in this embodiment, the sensible heat of the high-temperature hydrogen gas 8 released from the first-stage hydrogen storage container is used to heat the second-stage hydrogen storage container. The above technical solution solves the problem of wasted sensible heat from high-temperature hydrogen gas (8) and the need for additional energy to heat the second-stage material. Specifically, its working principle is as follows: During the hydrogen release step, the hydrogen gas (8) released in the first stage carries a large amount of sensible heat. When it flows into the second-stage hydrogen storage container, it directly transfers the heat to the low-temperature hydrogen storage material through the container wall. This achieves efficient heat recovery and cascade utilization within the system, further improving the overall energy utilization efficiency of the system.

[0035] Working principle: like Figure 2As shown, during the day, sunlight 7 passes through the light-transmitting window 2 and heats the absorption coating 3. The heat is conducted to the first-stage hydrogen storage tank 4, where Mg2NiH4 decomposes to release hydrogen gas 8. The high-temperature, high-pressure hydrogen gas 8 enters the second-stage hydrogen storage tank 5, where LaNi5H6 is heated to release hydrogen while being cooled. Finally, hydrogen gas 9 at a suitable pressure is output. like Figure 3 As shown, at night, external hydrogen source 8 10 fills the second-stage hydrogen storage tank 5 with hydrogen 8, and LaNi5 undergoes an exothermic reaction, with the heat being carried away by cold air 11 through the heat dissipation fins 6. When the second stage is saturated, hydrogen 8 enters the first-stage hydrogen storage tank 4, where Mg2Ni undergoes a hydrogen absorption reaction at a lower ambient temperature, and the heat of reaction is also dissipated. The control system (not shown) automatically manages valve switching and fan operation based on sensor data.

[0036] Those skilled in the art should understand that the discussion of any of the above embodiments is merely exemplary and is not intended to imply that the scope of the invention is limited to these examples; within the framework of the invention, the technical features of the above embodiments or different embodiments can also be combined, the steps can be implemented in any order, and there are many other variations of the different aspects of the invention as described above, which are not provided in detail for the sake of brevity.

[0037] This invention aims to cover all such substitutions, modifications, and variations that fall within the scope of protection. Therefore, any omissions, modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of this invention should be included within the scope of protection of this invention.

Claims

1. A multi-stage solid-state hydrogen storage system that utilizes photothermal regulation and temperature difference, characterized in that, include: A photothermal conversion cavity, at least a portion of which is a light-transmitting window (2), and the inner surface of the photothermal conversion cavity is provided with a solar energy absorption coating (3) for receiving and converting solar radiation energy into heat energy; The first-stage hydrogen storage container is located inside the photothermal conversion cavity to receive heat directly or indirectly; The second-stage hydrogen storage container is located outside the photothermal conversion cavity and connected in series with the first-stage hydrogen storage container through a pipeline, so that the hydrogen gas (8) released by the first-stage hydrogen storage container can enter and heat the second-stage hydrogen storage container. The temperature difference utilization and heat dissipation subsystem is used to utilize the ambient cold source to dissipate heat during the hydrogen absorption process of the second-stage hydrogen storage container; The intelligent control system controls the flow of the pipeline based on ambient temperature and system pressure to switch between hydrogen charging and discharging modes.

2. The multi-stage solid-state hydrogen storage system based on photothermal regulation and temperature difference utilization according to claim 1, characterized in that, The system also includes a thermal insulation layer (1) disposed on the outer surface of the photothermal conversion cavity.

3. The multi-stage solid-state hydrogen storage system based on photothermal regulation and temperature difference utilization according to claim 1, characterized in that, The photothermal conversion cavity is cylindrical, with the first-stage hydrogen storage container located on its central axis and the second-stage hydrogen storage container arranged around the outside of the photothermal conversion cavity.

4. The multi-stage solid-state hydrogen storage system based on photothermal regulation and temperature difference utilization according to claim 1, characterized in that, The first-stage hydrogen storage container is filled with high-temperature hydrogen storage material, and the second-stage hydrogen storage container is filled with low-temperature hydrogen storage material.

5. The multi-stage solid-state hydrogen storage system based on photothermal regulation and temperature difference utilization according to claim 4, characterized in that, The high-temperature hydrogen storage material is a magnesium-based hydrogen storage alloy with a hydrogen release temperature higher than 250°C; the low-temperature hydrogen storage material is a rare-earth-based or titanium-iron-based hydrogen storage alloy with a hydrogen release temperature lower than 100°C.

6. The multi-stage solid-state hydrogen storage system based on photothermal regulation and temperature difference utilization according to claim 1, characterized in that, The temperature difference utilization and heat dissipation subsystem includes heat dissipation fins (6) disposed outside the second-stage hydrogen storage container.

7. The multi-stage solid-state hydrogen storage system based on photothermal regulation and temperature difference utilization according to claim 1, characterized in that, The intelligent control system opens the hydrogen flow path from the first stage to the second stage under daylight conditions; at night or in low temperature environments, the intelligent control system prioritizes the introduction of hydrogen (8) into the second stage, and opens the flow path to the first stage after the second stage is saturated.

8. A method for storing hydrogen based on the system described in any one of claims 1-7, characterized in that, The method includes the following steps: Hydrogen release steps: During the day, sunlight (7) shines through the light-transmitting window (2) onto the absorption coating (3) to generate heat energy, which heats the first-stage hydrogen storage container to release hydrogen; the released high-temperature hydrogen gas (8) enters the second-stage hydrogen storage container, serving as a source of hydrogen gas (8) and a heat source to release hydrogen. Hydrogen absorption steps: At night or when the ambient temperature is low, external hydrogen (8) is first introduced into the second-stage hydrogen storage container, and the heat of hydrogen absorption reaction is carried away by the temperature difference and heat dissipation subsystem. When the second stage is close to saturation, hydrogen (8) is introduced into the first-stage hydrogen storage container to absorb hydrogen.

9. The method according to claim 8, characterized in that, The reaction heat generated when the second-stage hydrogen storage container absorbs hydrogen is dissipated through the heat dissipation fins (6) by natural convection or forced air cooling.

10. The method according to claim 8, characterized in that, During the hydrogen release process, the sensible heat of the high-temperature hydrogen gas (8) released from the first-stage hydrogen storage container is used to heat the second-stage hydrogen storage container.

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