Solid hydrogen storage tank filled with phase change heat storage unit and heat management and control method of solid hydrogen storage tank

Abstract

The invention discloses a solid hydrogen storage tank filled with a phase change heat storage unit and a heat management and control method of the solid hydrogen storage tank, and belongs to the technical field of solid hydrogen storage. The phase-change heat storage assembly comprises a plurality of phase-change heat storage units buried in a hydrogen storage material, and small phase-change heat storage units are filled in wall surface gaps; the control auxiliary assembly comprises a temperature sensor, a pressure sensor, a valve, a filter screen and a porous pressing plate; the thermal management and control method comprises the following steps of: introducing hydrogen with adaptive pressure during hydrogen storage, and absorbing heat and storing by a phase change unit; during hydrogen desorption, the pressure in the tank is regulated to an adaptive range, the phase change unit releases heat for dehydrogenation, and a proper temperature is maintained in the whole process. The phase change heat storage unit is in direct contact with the hydrogen storage material to strengthen heat exchange, so that hydrogen storage and release heat self-driving is realized, and the reaction rate and stability are improved; the structure is simplified, the maintenance difficulty and energy consumption are reduced, and multi-scene application is adapted.

Description

Technical Field

[0001] This invention relates to the field of solid-state hydrogen storage technology, and in particular to a solid-state hydrogen storage tank filled with a phase change thermal storage unit and its thermal management and control method. Background Technology

[0002] Solid-state hydrogen storage technology has become an important development direction in the field of hydrogen energy storage due to its advantages such as high hydrogen storage density and good safety. Its core is to use hydrogen storage materials such as metal hydrides and coordination hydrides to achieve efficient storage and release of hydrogen through reversible reactions of hydrogen absorption and release. However, the thermal management problem in the solid-state hydrogen storage process has always been the core bottleneck restricting the large-scale application of this technology: In the hydrogen absorption stage, the reaction between metal hydrides and hydrogen is a strongly exothermic reaction. If the heat generated by the reaction cannot be dissipated in time, the temperature of the hydrogen storage material bed will rise rapidly, the reaction kinetics will be sluggish, the hydrogen storage efficiency will be reduced, and even the hydrogen storage material will be pulverized and fail due to local overheating. In the hydrogen release stage, the decomposition of hydrogen storage materials to release hydrogen requires the absorption of a large amount of heat. If the environment cannot supply enough heat in time, the hydrogen release kinetics will be hindered, the hydrogen pressure will drop sharply, and the hydrogen release rate will be significantly reduced.

[0003] Currently, existing thermal management solutions for solid-state hydrogen storage tanks have significant shortcomings: some application scenarios lack effective thermal management systems, resulting in low hydrogen storage and release efficiency and failing to meet actual usage needs; other solutions employ additional heat transfer fluids for thermal management, which can alleviate temperature fluctuations to some extent, but requires additional energy consumption, significantly increasing the system's operating energy consumption. Phase change materials (PCMs), with their large latent heat of phase change and stable temperature during heat absorption and release, can serve as ideal thermal management media, enabling the recovery and reuse of heat during hydrogen storage and release, effectively reducing additional energy consumption, improving system energy utilization efficiency, and providing a feasible path to solve the problem of self-generated and self-used heat from hydrogen storage tanks.

[0004] However, existing coupling technologies between phase change materials and hydrogen storage tanks still have many problems: In the mainstream partitioned layout structure, the phase change material and hydrogen storage material are set up separately, resulting in a longer heat transfer path, a larger total thermal resistance, and low heat transfer efficiency; at the same time, uneven distribution of phase change materials is likely to occur, resulting in poor temperature control accuracy and uneven temperature distribution inside the hydrogen storage tank, and even the risk of local thermal runaway; in addition, the supporting components required for partitioned layout will occupy the effective space inside the hydrogen storage tank, reduce the hydrogen storage density, and make subsequent maintenance more difficult.

[0005] Another existing technology involves combining phase change materials (PCMs) with hydrogen storage materials to form composite blocks. The PCMs store and recover the heat released during the hydrogen absorption process of the hydrogen storage materials, which is then directly used for the dehydrogenation reaction. This technology replaces traditional heat exchangers or heat pipes with a mechanism of phase change heat storage and reaction heat recovery, eliminating the need for additional heating or heat exchange devices. However, this technology has a limited contact area between the PCMs and the hydrogen storage materials, resulting in insufficient heat transfer efficiency. Furthermore, the flexibility of the material combination is poor, making it difficult to adapt to different hydrogen storage scenarios.

[0006] Therefore, there is an urgent need to develop a solid hydrogen storage tank thermal management system that can achieve energy self-sufficiency, has a simple structure, a large heat exchange area, and high flexibility. Summary of the Invention

[0007] To address the aforementioned issues, this invention provides a solid-state hydrogen storage tank filled with phase change thermal storage units and its thermal management and control method. By employing a composite structure filled with phase change thermal storage units, coupled with a heat matching design and a temperature-pressure linkage control strategy, the invention achieves thermal self-driving of hydrogen storage and release, thereby improving hydrogen storage and release efficiency and safety. At the same time, the structure is simplified to adapt to various application scenarios.

[0008] The technical solution adopted by the present invention to solve its technical problem is: a solid hydrogen storage tank filled with a phase change thermal storage unit, comprising a hydrogen storage tank body, hydrogen storage material, phase change thermal storage component and control auxiliary component; The main body of the hydrogen storage tank includes an outer insulation area and a hydrogen storage tank shell. The outer insulation area wraps around the sides and top and bottom surfaces of the hydrogen storage tank shell. The hydrogen storage material is filled inside the hydrogen storage tank shell. The phase change thermal energy storage component includes several phase change thermal energy storage units, which are embedded in hydrogen storage material and densely distributed, and the phase change thermal energy storage units are in direct contact with the hydrogen storage material. The control auxiliary components include a temperature sensor, a pressure sensor, inlet and outlet valves, a safety valve, a filter screen, and a porous pressure plate. The top of the hydrogen storage tank shell is provided with a hydrogen inlet and outlet, the inlet and outlet valves are installed at the hydrogen inlet and outlet, and the filter screen is fixed at the top of the hydrogen storage tank shell near the hydrogen inlet and outlet; the pressure sensor and safety valve are both located on the top of the hydrogen storage tank shell, and the temperature sensor is located on the circumferential side of the hydrogen storage tank shell; the porous pressure plate is located above the hydrogen storage material and in close contact with the hydrogen storage material, and the edge of the porous pressure plate is in close contact with the inner wall of the hydrogen storage tank shell.

[0009] Furthermore, a number of springs are provided between the upper surface of the porous pressure plate and the inner top wall of the hydrogen storage tank shell. A number of grooves for limiting each spring are opened on the upper surface of the porous plate. The top end of the spring is welded and fixed to the inner wall of the hydrogen storage tank shell, and the bottom end abuts against the bottom surface of the corresponding groove.

[0010] Furthermore, the number of phase change thermal storage units satisfies the following condition: the total heat generated and absorbed during the hydrogen absorption and desorption process of the hydrogen storage material matches the total latent heat of phase change that the phase change thermal storage unit can absorb and release, and the heat matching follows the energy conservation relationship. In the formula, The total heat released / absorbed during the hydrogen storage and release process is expressed in kJ. This represents the amount of hydrogen gas, expressed in moles (mol). The heat of hydrogen absorption and desorption per unit mass of hydrogen storage material is expressed in kJ / mol. The mass of the phase change material is expressed in kg. The latent heat per unit mass of the phase change material is expressed in kJ / kg. The total latent heat that the phase change material can absorb / release is expressed in kJ.

[0011] Furthermore, the phase change thermal storage unit is encapsulated with phase change material, and the actual amount of phase change material used is the theoretical calculation value or 1-1.1 times the theoretical calculation value; the amount of hydrogen storage material used is more than 1.1 times the calculated value, which is determined according to the designed hydrogen storage capacity.

[0012] Furthermore, the phase change thermal storage units are arranged in a hexagonal close-packed, cubic close-packed, or cube-centered stacked manner, and adjacent phase change thermal storage units are in contact with each other and form a fixed structure.

[0013] Furthermore, the gap between the inner wall of the hydrogen storage tank shell and the phase change thermal storage unit is filled with a small phase change thermal storage unit with a diameter smaller than that of the phase change thermal storage unit.

[0014] Furthermore, the phase change thermal storage unit can be any one or more combinations of spherical, hexahedral, cylindrical, or capsule-shaped.

[0015] Furthermore, there are two temperature sensors, with the measurement points of the two sensors located at 1 / 4 and 3 / 4 of the height from the top of the hydrogen storage material, respectively; the filter screen is located away from the reaction area where the hydrogen storage material is located.

[0016] This invention also provides a thermal management and control method for a solid hydrogen storage tank filled with a phase change thermal storage unit. Based on the aforementioned solid hydrogen storage tank filled with a phase change thermal storage unit, the thermal management and control method includes a hydrogen storage process and a hydrogen release process; the hydrogen storage process includes the following steps: S11. Check whether the parameters of the temperature sensor and pressure sensor are within normal values; S12. If the parameters are normal, open the inlet valve in the inlet and outlet valves and introduce hydrogen into the hydrogen storage tank body according to the design pressure. S13. When the amount of hydrogen introduced reaches the theoretical design hydrogen filling capacity, close the inlet valve to complete the hydrogen storage. The hydrogen release process includes the following steps: S21. Open the outlet valve in the inlet and outlet valves to control the pressure inside the hydrogen storage tank to drop to the pressure required for hydrogen release; S22. Start the hydrogen release reaction and monitor the temperature of the hydrogen storage material bed in real time using a temperature sensor; S23. When the hydrogen release reaches the required level, close the outlet valve to complete the hydrogen release.

[0017] Furthermore, during hydrogen storage, the hydrogen storage material reacts with hydrogen to release heat, causing the temperature of the hydrogen storage material bed to rise. When the bed temperature exceeds the melting point of the phase change material, the phase change material melts and absorbs latent heat to lower the bed temperature. During hydrogen release, the hydrogen storage material undergoes a decomposition reaction and absorbs heat, causing the temperature of the hydrogen storage material bed to drop. When the bed temperature is lower than the freezing point of the phase change material, the phase change material solidifies and releases latent heat to supply the decomposition reaction.

[0018] The beneficial effects of this invention are: 1. This invention achieves heat recovery and reuse during the hydrogen storage and release process through thermal coupling between the phase change thermal storage unit and the hydrogen storage material, eliminating the need for additional heat sources. Combined with heat matching design and dense stacking arrangement, it eliminates reaction dead zones, stably controls bed temperature, and reduces reaction kinetic lag caused by overheating and overcooling. The direct contact between the phase change thermal storage unit and the hydrogen storage material shortens the heat transfer path, enhances heat exchange efficiency, and increases the rate of hydrogen storage and release reactions, making the reaction process more stable and smooth.

[0019] 2. This invention uses an integrated structure to replace an additional heat exchange device, simplifying the system complexity; the combination of porous pressure plate and spring adapts to the volume change of hydrogen storage material, continuously ensuring the effectiveness of material contact; the phase change heat storage unit is easy to fill and replace, and the filter screen can block pulverized particles, greatly reducing the maintenance difficulty and cost of the device.

[0020] 3. This invention reduces thermal interference between the inside and outside of the tank through the outer insulation zone, and the configuration of temperature and pressure sensors for real-time monitoring and emergency pressure relief valves prevents risks such as overheating and abnormal pressure. The encapsulation structure of the phase change thermal storage unit avoids leakage of phase change materials and corrosion of the tank, effectively extending the cycle life of the device.

[0021] 4. This invention is a thermally self-driven mode that requires no additional energy consumption, and the simplified structure reduces manufacturing costs; it can be adapted to different hydrogen storage materials, phase change materials and hydrogen absorption and desorption conditions, and its compact structure makes it suitable for various application scenarios such as mobile and portable applications. Attached Figure Description

[0022] Figure 1 This is a schematic diagram illustrating the arrangement of two consecutive phase change thermal storage units in the hydrogen storage tank in this invention.

[0023] Figure 2This is a structural cross-sectional view of the present invention.

[0024] Figure 3 This is a schematic diagram of the shapes of different phase change thermal storage units in this invention.

[0025] Figure 4 This is a schematic diagram of the porous pressure plate in this invention.

[0026] Figure 5 This is a flowchart of the thermal management and control method in this invention.

[0027] In the diagram: 1. Inlet / outlet valve; 2. Pressure sensor; 3. Safety valve; 4. Filter screen; 5. Spring; 6. Phase change thermal energy storage unit; 7. Small phase change thermal energy storage unit; 8. Hydrogen storage material; 9. Temperature sensor; 10. Hydrogen storage tank shell; 11. Porous pressure plate; 12. Outer insulation area; 13. Phase change sphere; 14. Phase change cube; 15. Phase change cylinder; 16. Phase change capsule and other shapes of phase change energy storage units; 17. Groove; 18. Hole. Detailed Implementation

[0028] The present invention will be further described in detail below with reference to the accompanying drawings.

[0029] This invention discloses a solid hydrogen storage tank filled with phase change thermal storage units, aiming to solve the technical pain points of existing solid hydrogen storage tanks, such as large temperature fluctuations in the bed, low thermal management efficiency, complex structure, and short cycle life. Through the synergistic design of micro-unitized phase change materials and solid hydrogen storage materials, the heat self-sufficiency and efficient thermal coupling of the hydrogen storage and release process are achieved, thereby improving the thermal stability, hydrogen storage and release rate, and safety of the hydrogen storage tank.

[0030] Reference Figure 1 and Figure 2 A solid hydrogen storage tank filled with a phase change thermal storage unit includes a hydrogen storage tank body, a hydrogen storage material 8, a phase change thermal storage component, and control auxiliary components. The hydrogen tank body includes an outer insulation zone 12 and a hydrogen storage tank shell 10. The outer insulation zone 12 completely covers the sides and top and bottom surfaces of the hydrogen storage tank shell 10. Its core function is to block heat exchange between the inside and outside of the tank, preventing the loss of reaction heat during hydrogen storage and release, and reducing the interference of external ambient temperature changes on the internal temperature distribution of the tank, thus providing an insulating environment for the efficient thermal coupling of the hydrogen storage material 8 and the phase change thermal storage unit 6.

[0031] The hydrogen storage material 8 is a metal hydride or coordination hydride, which is filled inside the outer shell 10 of the hydrogen storage tank. Its amount is set to be more than 1.1 times the value calculated according to the designed hydrogen storage capacity. This is because the hydrogen storage efficiency of the hydrogen storage material 8 is about 90% in the actual hydrogen storage and release process. By appropriately increasing the amount, the device can be guaranteed to meet the preset hydrogen storage and release capacity requirements.

[0032] The phase change thermal energy storage component includes several phase change thermal energy storage units 6, which are embedded in hydrogen storage material 8 and densely stacked, and are in direct contact with hydrogen storage material 8. This integrated structure does not require an additional heat exchanger, which can significantly shorten the heat transfer path, reduce the total thermal resistance, and avoid the heat transfer dead zone problem caused by traditional zoning.

[0033] The phase change thermal storage unit 6 is encapsulated with phase change material. The selection of phase change material is matched with the operating temperature of hydrogen storage material 8. It is suitable for hydrogen absorption and release conditions ranging from room temperature to 500°C. Materials with high latent heat of phase change are preferred to improve heat storage and release efficiency.

[0034] To more clearly illustrate the compatibility logic between phase change materials and hydrogen storage materials 8, we now select Hydrogen storage alloy is a hydrogen storage material. 8. Encapsulation Taking the storage of hydrogen in phase change thermal storage unit 6 as an example, the reaction formula is as follows: From this reaction equation, it can be seen that... The heat released or absorbed by the hydrogen storage alloy during the hydrogenation / dehydrogenation reaction reaches 30.1. Hydrogen absorption reactions can proceed spontaneously at room temperature, releasing a large amount of heat, while dehydrogenation reactions often require temperatures above 40°C to proceed efficiently, necessitating continuous heating to overcome the reaction energy barrier. Based on this... Hydrogen storage alloys' hydrogen absorption and desorption properties allow for targeted selection of encapsulation materials. The phase change thermal storage unit 6 of the medium has a phase change temperature of about 30℃ and a latent heat of phase change of 296kJ / kg. The heat released by the hydrogen absorption reaction of the hydrogen storage alloy at room temperature can be... The phase change material rapidly absorbs the heat, causing a phase change to occur when its temperature rises to 30°C, transforming it from a solid to a liquid state, and stably storing the heat of reaction as latent heat; during the hydrogen release phase, when... When the hydrogen storage alloy decomposes and requires heat, the phase change material undergoes another phase change, transforming from a liquid to a solid state and releasing the stored latent heat. This provides a continuous and stable heat supply for the dehydrogenation reaction, thereby achieving self-driven heating without the need for an external heat source.

[0035] The number of phase change thermal storage units 6 must meet the heat matching requirement: that is, the total heat generated and absorbed by the hydrogen storage material 8 during hydrogen absorption and desorption must be completely matched with the total latent heat of phase change that the phase change thermal storage units 6 can absorb and release; this matching relationship follows the law of conservation of energy. In the formula, The total heat released / absorbed during the hydrogen storage and release process is expressed in kJ. This represents the amount of hydrogen gas, expressed in moles (mol). The heat of hydrogen absorption and desorption per unit mass of hydrogen storage material is expressed in kJ / mol. The mass of the phase change material is expressed in kg. The latent heat per unit mass of the phase change material is expressed in kJ / kg. The total latent heat that the phase change material can absorb / release is expressed in kJ.

[0036] The calculation of this energy conservation relationship is derived based on the ideal assumptions of adiabatic hydrogen storage tank, neglecting sensible heat changes, and 100% hydrogen absorption / desorption efficiency. In practical applications, the amount of phase change material used is 1-1.1 times the theoretical calculation value mentioned above. This is to take into account the heat loss that occurs during the actual hydrogen storage and desorption process, as the heat generated by the hydrogen storage reaction cannot be completely absorbed by the phase change material. The additional 0-10% can be used as a safety margin to ensure the reliability of temperature control.

[0037] The phase change thermal storage units 6 are arranged in a hexagonal close-packed, cubic close-packed, or cubic core-packed manner. Adjacent units are in contact with each other and form a stable fixed structure, which maximizes the filling density and ensures the continuity of heat transfer. At the same time, in view of the problem that the gap between the inner wall of the hydrogen storage tank shell 10 and the phase change thermal storage unit 6 is prone to forming a reaction dead zone, that is, a region where the hydrogen absorption and desorption reaction of the hydrogen storage material 8 is almost stagnant within a certain temperature and pressure range, a small phase change thermal storage unit 7 with a diameter smaller than the main phase change thermal storage unit 6 is filled in the gap to eliminate the reaction dead zone and ensure that the reaction kinetics of each region of the hydrogen storage material 8 in the tank are consistent.

[0038] Reference Figure 3 The shape of the phase change thermal storage unit 6 can be flexibly selected, and can be any of the phase change thermal storage units 16 in other shapes such as phase change sphere 13, phase change cube 14, phase change cylinder 15 or phase change capsule. The internal space volume of a single phase change thermal storage unit 6 is equal to or slightly larger than the volume of the phase change material it encapsulates when it melts, so as to cope with the volume expansion during the melting process of the phase change material and avoid the thermal storage unit shell from cracking due to expansion stress. At the same time, the encapsulation structure can also effectively prevent the leakage of phase change material and corrosion of the tank, and improve the overall mechanical strength and durability.

[0039] The control auxiliary components include a temperature sensor 9, a pressure sensor 2, an inlet / outlet valve 1, a safety valve 3, a filter screen 4, and a porous pressure plate 11. The top of the hydrogen storage tank shell 10 is equipped with a hydrogen inlet / outlet. The inlet / outlet valve 1 is installed at the hydrogen inlet / outlet to regulate the flow of hydrogen. The diameter of the hydrogen inlet / outlet is at least larger than the diameter of the phase change thermal storage unit 6 to facilitate the filling and replacement of the phase change thermal storage unit 6.

[0040] The filter screen 4 is fixed at the top of the outer shell 10 of the hydrogen storage tank, near the hydrogen inlet and outlet, and far away from the reaction area where the hydrogen storage material 8 is located. Its function is to prevent the particles generated by the pulverization of the hydrogen storage material 8 during the hydrogen absorption and desorption cycle from entering the pipeline with the gas flow, thus avoiding material loss and pipeline blockage. At the same time, being far away from the reaction area can avoid the thermal effects of hydrogenation and dehydrogenation reactions that could cause the filter screen 4 to deform or be damaged, thus ensuring its long-term stability.

[0041] Pressure sensor 2 and safety valve 3 are both located on the top of the hydrogen storage tank shell 10. Pressure sensor 2 is used to monitor the hydrogen pressure inside the tank in real time, and safety valve 3 is connected to the outdoor environment, allowing for emergency pressure relief in case of abnormal pressure inside the tank, thus preventing safety risks caused by the flammability and explosiveness of hydrogen. Temperature sensors 9 are located on the circumferential side of the hydrogen storage tank shell 10, with two sensors at measurement points located at 1 / 4 and 3 / 4 of the height from the top of the hydrogen storage material 8, respectively. This arrangement allows for more comprehensive monitoring of the temperature distribution of the hydrogen storage material 8 bed, ensuring timely capture of temperature changes in different areas of the bed and providing data support for thermal management control.

[0042] Reference Figure 4 A porous pressure plate 11 is positioned above the hydrogen storage material 8 and in close contact with it, with its edges tightly abutting the inner wall of the hydrogen storage tank shell 10. The upper surface of the porous pressure plate 11 is densely covered with several holes 18 and has four centrally symmetrical grooves 17 for limiting and fixing several springs 5. The top of the springs 5 ​​is welded and fixed to the inner wall of the hydrogen storage tank shell 10, and the bottom end abuts against the bottom surface of the corresponding groove 17. The welding process adopts argon arc welding or laser welding to ensure the strength and sealing of the welded joint. Spring 5 is a high-temperature resistant and fatigue-resistant metal compression spring. Initially, it is in a slightly compressed state, ensuring that the porous pressure plate 11 always applies a preset pressure to the hydrogen storage material 8. Since the hydrogen storage material 8 undergoes a 10%-30% volume change during the hydrogen absorption and desorption reaction, when the hydrogen storage material 8 expands, it pushes the porous pressure plate 11 to compress the spring 5. The spring 5 absorbs the expansion thrust through elastic deformation, preventing abnormal pressure increases inside the tank. When the hydrogen storage material 8 contracts, the spring 5, under the action of elastic restoring force, pushes the porous pressure plate 11 downwards, ensuring that the pressure plate remains in close contact with the hydrogen storage material 8, preventing material loosening and the formation of voids, ensuring effective contact between the hydrogen storage material 8 and the phase change thermal storage unit 6, and maintaining uniform heat transfer. Furthermore, the porous structure of the porous pressure plate 11 reduces its own weight and provides a channel for hydrogen diffusion, without affecting the normal progress of the hydrogen storage and desorption reaction.

[0043] This invention also discloses a thermal management and control method for a solid hydrogen storage tank filled with a phase change thermal storage unit, including a hydrogen storage process and a hydrogen release process. Its core is to utilize the latent heat of phase change of the phase change material to achieve the recovery and reuse of the reaction heat, forming a passive thermal management system that requires no additional energy consumption. The following... Hydrogen storage alloy is a hydrogen storage material. 8. Encapsulation Taking the phase change thermal storage unit 6 as an example, the thermal management and control methods are explained: The hydrogen storage process includes the following steps: S11. First, check whether the parameters of temperature sensor 9 and pressure sensor 2 are within normal values ​​to ensure that the initial state inside the tank is safe and controllable. S12. If the parameters are normal, open the inlet valve in inlet / outlet valve 1 and adjust the hydrogen pressure to... The hydrogen storage alloy absorbs hydrogen at a pressure of 1 MPa to 5 MPa, and hydrogen is introduced into the hydrogen storage tank. This pressure range is adapted to the hydrogen absorption reaction characteristics of the hydrogen storage material 8, which can ensure that the hydrogen absorption reaction proceeds efficiently. S13. When the amount of hydrogen introduced reaches the theoretical design hydrogen filling amount, close the inlet valve to complete the hydrogen storage.

[0044] During hydrogen storage, hydrogen storage materials The reaction with hydrogen releases a large amount of heat, causing the hydrogen storage material to... The bed temperature rises rapidly; when the bed temperature exceeds the melting point of the phase change material, the phase change material begins to melt. During the melting process, it absorbs a large amount of latent heat, which can rapidly reduce the bed temperature and allow the hydrogen storage material to cool down during hydrogen storage. The bed temperature is controlled between 20°C and 25°C to avoid local overheating and damage to the hydrogen storage material. Kinetic hysteresis or pulverization failure.

[0045] The hydrogen release process includes the following steps: S21. Open the outlet valve in inlet / outlet valve 1 to control the pressure inside the hydrogen storage tank to decrease. The hydrogen release pressure of the hydrogen storage alloy is 0.1 MPa to 0.3 MPa, a pressure range suitable for hydrogen storage materials. The dehydrogenation reaction provides suitable conditions; S22. Initiate the hydrogen release reaction and monitor the hydrogen storage material in real time using temperature sensor 9. Bed temperature; S23. When the hydrogen release reaches the required level, close the outlet valve to complete the hydrogen release.

[0046] During hydrogen release, hydrogen storage materials A decomposition reaction occurs, absorbing a large amount of heat, causing the bed temperature to drop rapidly; when the bed temperature falls below that of the phase change material... At its freezing point of 30°C, the phase change material begins to solidify, releasing a large amount of latent heat during the solidification process. This provides a continuous heat supply for the dehydrogenation reaction, ensuring the hydrogen storage material is protected during hydrogen release. The bed temperature is controlled between 25°C and 50°C to avoid insufficient ambient heat supply, which could hinder hydrogen release kinetics and cause a sudden drop in hydrogen pressure, thus ensuring a stable hydrogen release rate.

[0047] This thermal management and control method achieves thermal self-driving of the hydrogen storage and release process by linking pressure and temperature control and combining the heat absorption and release characteristics of the phase change thermal storage unit 6. This not only significantly reduces heat loss and system energy consumption, but also simplifies the structure of the hydrogen storage tank, making it more compact, easier to operate and maintain, and suitable for various application scenarios such as mobile and portable systems.

[0048] Based on the above-described preferred embodiments of the present invention, and through the foregoing description, those skilled in the art can make various changes and modifications without departing from the inventive concept. The technical scope of this invention is not limited to the contents of the specification, but must be determined according to the scope of the claims.

Claims

1. A solid hydrogen storage tank filled with a phase change thermal storage unit, characterized in that: Includes the main body of the hydrogen storage tank, hydrogen storage material (8), phase change thermal storage components and control auxiliary components; The main body of the hydrogen storage tank includes an outer insulation area (12) and a hydrogen storage tank shell (10). The outer insulation area (12) wraps around the sides and top and bottom surfaces of the hydrogen storage tank shell (10). The hydrogen storage material (8) is filled inside the hydrogen storage tank shell (10). The phase change thermal storage component includes several phase change thermal storage units (6), which are embedded in hydrogen storage material (8) and densely distributed, and the phase change thermal storage units (6) are in direct contact with the hydrogen storage material (8). The control auxiliary components include a temperature sensor (9), a pressure sensor (2), an inlet and outlet valve (1), a safety valve (3), a filter screen (4), and a porous pressure plate (11); The top of the hydrogen storage tank shell (10) is provided with a hydrogen inlet and outlet. The inlet and outlet valves (1) are installed at the hydrogen inlet and outlet. The filter screen (4) is fixed at the top of the hydrogen storage tank shell (10) near the hydrogen inlet and outlet. The pressure sensor (2) and the safety valve (3) are both located on the top of the hydrogen storage tank shell (10). The temperature sensor (9) is located on the circumferential side of the hydrogen storage tank shell (10). The porous pressure plate (11) is located above the hydrogen storage material (8) and is in close contact with the hydrogen storage material (8). The edge of the porous pressure plate (11) is in close contact with the inner wall of the hydrogen storage tank shell (10).

2. A solid hydrogen storage tank filled with a phase change thermal storage unit according to claim 1, characterized in that: A plurality of springs (5) are provided between the upper surface of the porous pressure plate (11) and the inner top wall of the hydrogen storage tank shell (10). A plurality of grooves (17) for limiting each spring (5) are provided on the upper surface of the porous plate. The top end of each spring (5) is welded and fixed to the inner wall of the hydrogen storage tank shell (10), and the bottom end abuts against the bottom surface of the corresponding groove (17).

3. A solid hydrogen storage tank filled with a phase change thermal storage unit according to claim 2, characterized in that: The number of phase change thermal storage units (6) satisfies the following condition: the total heat generated and absorbed by the hydrogen storage material (8) during hydrogen absorption and desorption is matched with the total latent heat of phase change that the phase change thermal storage unit (6) can absorb and release, and the heat matching follows the energy conservation relationship. In the formula, The total heat released / absorbed during the hydrogen storage and release process is expressed in kJ. This represents the amount of hydrogen gas, expressed in moles (mol). The heat of hydrogen absorption and desorption per unit mass of hydrogen storage material is expressed in kJ / mol. The mass of the phase change material is expressed in kg. The latent heat per unit mass of the phase change material is expressed in kJ / kg. The total latent heat that the phase change material can absorb / release is expressed in kJ.

4. A solid hydrogen storage tank filled with a phase change thermal storage unit according to claim 3, characterized in that: The phase change thermal storage unit (6) is encapsulated with phase change material, and the actual amount of phase change material used is the theoretical calculation value or 1-1.1 times the theoretical calculation value; the amount of hydrogen storage material (8) used is more than 1.1 times the calculated value, which is determined according to the designed hydrogen storage capacity.

5. A solid hydrogen storage tank filled with a phase change thermal storage unit according to claim 4, characterized in that: The phase change thermal storage units (6) are arranged in a hexagonal close-packed, cubic close-packed, or cubic core-packed manner, and adjacent phase change thermal storage units (6) are in contact with each other and form a fixed structure.

6. A solid hydrogen storage tank filled with a phase change thermal storage unit according to claim 5, characterized in that: The gap between the inner wall of the hydrogen storage tank shell (10) and the phase change thermal storage unit (6) is filled with a small phase change thermal storage unit (7) with a diameter smaller than that of the phase change thermal storage unit (6).

7. A solid hydrogen storage tank filled with a phase change thermal storage unit according to claim 6, characterized in that: The phase change thermal storage unit (6) is shaped as any one or more combinations of sphere, hexahedron, cylinder or capsule.

8. A solid hydrogen storage tank filled with a phase change thermal storage unit according to claim 7, characterized in that: The number of temperature sensors (9) is two, and the measurement points of the two temperature sensors (9) are located at 1 / 4 height and 3 / 4 height from the top of the hydrogen storage material (8), respectively; the filter (4) is far away from the reaction area where the hydrogen storage material (8) is located.

9. A method for thermal management and control of a solid hydrogen storage tank filled with a phase change thermal storage unit, characterized in that: The solid hydrogen storage tank based on the phase change thermal storage unit as described in claim 8 has a thermal management and control method that includes a hydrogen storage process and a hydrogen release process; the hydrogen storage process includes the following steps: S11. Check whether the parameters of the temperature sensor (9) and pressure sensor (2) are within normal values; S12. If the parameters are normal, open the inlet valve in the inlet and outlet valve (1) and introduce hydrogen into the hydrogen storage tank body according to the design pressure. S13. When the amount of hydrogen introduced reaches the theoretical design hydrogen filling capacity, close the inlet valve to complete the hydrogen storage. The hydrogen release process includes the following steps: S21. Open the outlet valve in the inlet and outlet valve (1) to control the pressure inside the hydrogen storage tank to drop to the hydrogen release pressure. S22, start the hydrogen release reaction and monitor the temperature of the hydrogen storage material (8) bed in real time through temperature sensor (9); S23. When the hydrogen release reaches the required level, close the outlet valve to complete the hydrogen release.

10. The thermal management and control method for a solid hydrogen storage tank filled with a phase change thermal storage unit according to claim 9, characterized in that: During hydrogen storage, the hydrogen storage material (8) reacts with hydrogen to release heat, causing the temperature of the hydrogen storage material (8) bed to rise. When the bed temperature exceeds the melting point of the phase change material, the phase change material melts and absorbs latent heat to reduce the bed temperature. During hydrogen release, the hydrogen storage material (8) undergoes a decomposition reaction and absorbs heat, causing the temperature of the hydrogen storage material (8) bed to drop. When the bed temperature is lower than the freezing point of the phase change material, the phase change material solidifies and releases latent heat to supply the decomposition reaction.

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