Hydrogen storage reactor and device based on partitioned arrangement of phase change material and metal hydride

Abstract

This invention belongs to the field of solid-state hydrogen storage reactors, and provides a hydrogen storage reactor and apparatus based on a partitioned arrangement of phase change materials and metal hydrides. The hydrogen storage reactor includes a reactor body, a hydrogen inlet channel, an expansion zone, an outer shell, and baffles. The hydrogen inlet channel is used to introduce hydrogen. The expansion zone is used to temporarily store and uniformly distribute the incoming hydrogen, while mitigating pressure fluctuations and the volume expansion of the metal hydrides. The baffles divide the reactor body into several regions. In these regions, phase change materials and metal hydrides are alternately arranged, allowing the reaction heat released by the metal hydrides during hydrogen storage to be simultaneously transferred to the phase change materials in adjacent regions through the side walls of its respective region, thereby increasing the effective heat transfer area.

Description

Technical Field

[0001] This invention belongs to the field of solid-state hydrogen storage reactors, and particularly relates to a hydrogen storage reactor and apparatus based on a partitioned arrangement of phase change materials and metal hydrides. Background Technology

[0002] The statements in this section are merely background information related to the present invention and do not necessarily constitute prior art.

[0003] Metal hydride hydrogen storage technology boasts advantages such as high volumetric hydrogen storage density, good reversibility and cycleability, and high safety. However, the hydrogen storage and release reactions of metal hydrides involve strong thermal effects, requiring an efficient thermal management system to maintain suitable reaction temperatures. Thermal management methods for metal hydride hydrogen storage are mainly divided into two categories: active and passive. Active thermal management primarily involves embedding pipes carrying heat exchange fluids within the hydrogen storage reactor to remove and supply heat during hydrogen storage and release. Extensive research has been conducted on the impact of parameters such as the number, shape, and size of heat exchange tubes on hydrogen storage and release performance.

[0004] However, active thermal management methods suffer from drawbacks such as high energy consumption and system complexity. During hydrogen storage, the heat of reaction released by the metal hydride is absorbed by the heat exchange fluid and dissipated into the air. Furthermore, during hydrogen release, additional heat is required to drive hydrogen desorption, resulting in low energy utilization. Therefore, to fully recover the heat of reaction, phase change materials (PCMs) are used to replace embedded heat exchange tubes. The melting and solidification characteristics of PCMs enable the recovery and supply of heat of reaction, fully leveraging the reactor's self-driving thermal advantage and thus improving energy utilization. However, existing solid-state hydrogen storage reactors coupled with PCMs suffer from low hydrogen storage efficiency due to a single heat transfer path and uneven temperature distribution. Summary of the Invention

[0005] To address the technical problems mentioned above, this invention provides a hydrogen storage reactor and apparatus based on a partitioned arrangement of phase change materials and metal hydrides. This reactor can increase the heat transfer path and improve the uniformity of temperature distribution by alternating partitioned arrangements of phase change materials and metal hydrides, thereby improving hydrogen storage efficiency.

[0006] To achieve the above objectives, the present invention adopts the following technical solution:

[0007] The first aspect of the present invention provides a hydrogen storage reactor based on a partitioned arrangement of phase change materials and metal hydrides.

[0008] A hydrogen storage reactor based on a partitioned arrangement of phase change materials and metal hydrides includes a reactor body, a hydrogen inlet channel, an expansion zone, an outer shell, and baffles. The hydrogen inlet channel is used to introduce hydrogen. The expansion zone is used to temporarily store and uniformly distribute the incoming hydrogen, while mitigating pressure fluctuations and the volume expansion of the metal hydrides. The baffles divide the reactor body into several regions. In these regions, phase change materials and metal hydrides are alternately arranged, so that the reaction heat released by the metal hydrides during hydrogen storage is simultaneously transferred to the phase change materials in adjacent regions through the side walls of its respective region, thereby increasing the effective heat transfer area.

[0009] In one embodiment, the partition is divided into multiple honeycomb-shaped chambers by a honeycomb partitioning method.

[0010] In one implementation, a metal hydride is placed in the central honeycomb chamber, and the honeycomb chambers from the center outwards are alternately filled with phase change material and hydrogen storage material.

[0011] In one embodiment, the partition is used to divide the hydrogen storage reactor body in a fan-shaped partition manner.

[0012] In one embodiment, the partition plate divides the hydrogen storage reactor body in a triangular partitioning manner.

[0013] In one implementation, the partition is divided into sections of the hydrogen storage reactor body using a regular polygonal partitioning method.

[0014] As one implementation method, phase change materials with different phase change temperatures are arranged in a tiered manner within the region where the phase change material is located.

[0015] As one implementation method, the phase change material placed in the region dominated by natural convection has the highest temperature within the area where the phase change material is located.

[0016] As one implementation method, the phase change material is placed in the area dominated by thermal conductivity within the region where the phase change material is located, where the temperature is lowest.

[0017] A second aspect of the present invention provides an energy supply device.

[0018] An energy supply device includes a hydrogen storage reactor as described above, which is based on a partitioned arrangement of phase change materials and metal hydrides.

[0019] The beneficial effects of this invention are:

[0020] (1) This invention proposes a hydrogen storage reactor based on the partitioned arrangement of phase change material and metal hydride. During the hydrogen storage process, the phase change material is used to store the reaction heat released by the metal hydride and is utilized during the hydrogen release process. This solves the problem of complex system and high energy consumption caused by traditional solid hydrogen storage reactors, thereby realizing the self-driven circulation of heat and improving energy utilization.

[0021] (2) The partitioned arrangement of phase change material and hydrogen storage material in the solid hydrogen storage reactor proposed in this invention can increase the effective heat transfer area, widen the heat transfer path, and reduce the average heat conduction distance, so that the entire reactor can operate under more uniform and stable temperature conditions. This solves the problems of poor heat exchange performance and low hydrogen storage rate of existing solid hydrogen storage reactors with coupled phase change materials, avoids local overheating or overcooling, and thus improves the hydrogen storage rate and efficiency.

[0022] (3) The metal hydride hydrogen storage reactor based on phase change material stepped arrangement proposed in this invention solves the problem of low hydrogen storage efficiency caused by uneven temperature distribution by uniformly arranging phase change materials with different phase change temperatures and latent heat values ​​along the axial direction of the reactor, optimizes heat management, reduces energy waste, and thus significantly improves hydrogen storage efficiency.

[0023] (4) The hydrogen storage reactor based on the partitioned arrangement of phase change materials and metal hydrides proposed in this invention can be applied to the field of mobile hydrogen storage, such as fuel cell vehicles, drones, and other devices that require efficient and lightweight hydrogen storage systems. By optimizing heat management, energy utilization can be improved and the endurance of the devices can be extended. This design effectively solves the problems of high energy consumption and low efficiency in traditional hydrogen storage systems, improves the performance and reliability of mobile devices, and meets the requirements of modern mobile hydrogen storage technology for high efficiency, portability, and high energy density.

[0024] Advantages of additional aspects of the invention will be set forth in part in the description which follows, and in part will be obvious from the description, or may be learned by practice of the invention. Attached Figure Description

[0025] The accompanying drawings, which form part of this invention, 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 improper limitation of the invention.

[0026] Figure 1 This is a schematic diagram of a traditional solid-state hydrogen storage reactor coupled with phase change materials.

[0027] Figure 2 This is a schematic diagram of the hydrogen storage reactor based on the partitioned arrangement of phase change materials and metal hydrides according to the present invention.

[0028] Figure 3(a) is a comparison of the metal hydride reaction fraction and average temperature over time for the comparative example and Example 1 of the present invention.

[0029] Figure 3(b) is a comparison of the reaction fraction distribution of the comparative example and Example 1 of the present invention at different times;

[0030] Figure 4 This is a schematic diagram of a solid hydrogen storage reactor based on a tiered arrangement of phase change materials.

[0031] Figure 5 This is a schematic diagram of a solid hydrogen storage reactor based on a honeycomb partitioned arrangement of phase change materials and metal hydrides.

[0032] Among them, 1 is the hydrogen inlet channel, 2 is the expansion zone, 3 is the metal hydride bed, 4 is the inner tube, 5 is the phase change material, 6 is the outer shell, and 7 is the partition. Detailed Implementation

[0033] The present invention will be further described below with reference to the accompanying drawings and embodiments.

[0034] It should be noted that the following detailed description is illustrative and intended to provide further explanation of the invention. Unless otherwise specified, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention pertains.

[0035] 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 scope of exemplary embodiments according to the invention. 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.

[0036] In this invention, terms such as "upper," "lower," "left," "right," "front," "back," "vertical," "horizontal," "side," and "bottom" indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. These terms are used only to facilitate the description of the structural relationships of the various components or elements of this invention and do not specifically refer to any component or element in this invention. They should not be construed as limiting the invention.

[0037] In this invention, terms such as "fixed connection," "connected," and "linked" should be interpreted broadly, indicating a fixed connection, an integral connection, or a detachable connection; a direct connection or an indirect connection through an intermediate medium. Those skilled in the art can determine the specific meaning of these terms in this invention based on the specific circumstances, and they should not be construed as limitations on the invention.

[0038] Traditional solid-state hydrogen storage reactors coupled with phase change materials, such as Figure 1 As shown, it includes an outer shell 6, an inner tube 4, an expansion zone 2, and a hydrogen inlet channel 1. The inner tube 4 is made of steel, and the outer shell 6 is made of PB. The inner tube 4 is filled with a metal hydride bed 3, and the outer shell 6 is filled with a phase change material 5. Hydrogen is introduced through the hydrogen inlet channel 1 at the top. The expansion zone 2 is used to temporarily store and uniformly distribute the introduced hydrogen, while also mitigating pressure fluctuations and the volume expansion of the metal hydride. The reaction heat released by the metal hydride during hydrogen storage is transferred to the phase change material through the side wall of the inner tube. After absorbing the heat, the phase change material undergoes a phase change and stores the heat in the form of sensible heat and latent heat.

[0039] Comparative example:

[0040] The reactor has a total length of 50 mm, an inner tube inner radius of 12 mm, an outer shell inner radius of 19 mm, an inner tube thickness of 1 mm, a metal hydride of LaNi5, a phase change material of LiNO3·3H2O, an initial temperature of 293.15 K, an initial pressure of 0.143 MPa (equilibrium pressure at the initial temperature), an initial density of the metal hydride (density before hydrogen absorption), and a hydrogen supply pressure of 0.8 MPa.

[0041] This invention provides a simple and efficient metal hydride solid-state hydrogen storage reactor coupled with a phase change material (PCM). The heat transfer path is increased through a partitioned arrangement of the PCM and the metal hydride, thereby improving the hydrogen storage rate. In one or more embodiments, the provided hydrogen storage reactor based on a partitioned arrangement of the PCM and the metal hydride is as follows: Figure 2 As shown, the reactor includes a hydrogen storage reactor body, an outer shell 6, a partition 7, an expansion zone 2, and a hydrogen inlet channel 1. The partition 7 divides the hydrogen storage reactor body into several regions. In these regions, phase change material 5 and metal hydride beds 3 are alternately arranged, so that the reaction heat released by the metal hydride during hydrogen storage is simultaneously transferred to the phase change material in the adjacent regions through the side walls of its respective region, thereby increasing the effective heat transfer area. Hydrogen is introduced through the hydrogen inlet channel 1 at the top. The reaction heat released by the metal hydride during hydrogen storage is simultaneously transferred to the phase change material in the adjacent regions through the side walls of its respective region, increasing the effective heat transfer area and widening the heat transfer path.

[0042] Example 1:

[0043] With the same mass of metal hydride and phase change material as the comparative example, the reactor was divided circumferentially into 5 metal hydride sections with a central angle of 28.72° and 5 phase change material sections with a central angle of 43.28° using 10 baffles. The thickness of the baffles was 1 mm. Similarly, the metal hydride was LaNi5, the phase change material was LiNO3·3H2O, the initial temperature was 293.15 K, the initial pressure was the equilibrium pressure corresponding to the initial temperature of 0.143 MPa, the initial density of the metal hydride was the density in the state without hydrogen absorption, and the hydrogen supply pressure was 0.8 MPa.

[0044] To intuitively explain the advantages of alternating zonal arrangements of phase change materials (PCMs) and metal hydrides, a multiphysics model was established, and numerical calculations were performed. The results are shown in Figures 3(a) and 3(b). Figure 3(a) shows that, under the same hydrogen storage capacity, compared to a traditional solid-state hydrogen storage reactor, the hydrogen storage time of the solid-state hydrogen storage reactor based on the zonal arrangement of PCMs and hydrogen storage materials is shortened by 67.13%. Figure 3(b) shows that in traditional reactors, the high temperature at the center is difficult to cool due to the single and limited heat transfer surface. The reactor proposed in this invention increases the heat transfer area, reduces the heat conduction distance, and accelerates the hydrogen storage rate. Therefore, by alternating the arrangement of PCMs and metal hydrides, not only is the hydrogen storage rate improved, but the uniformity of temperature distribution is also enhanced, demonstrating significant application potential.

[0045] Figure 2 The hydrogen storage reactor body is partitioned in a sector-shaped manner.

[0046] It should be noted that the partitioning method of the hydrogen storage reactor body also includes, but is not limited to, triangular, honeycomb, and regular polygon shapes.

[0047] In other embodiments, a solid-state hydrogen storage reactor with a honeycomb-like partitioned arrangement is provided, such as... Figure 5 As shown, the hydrogen storage reactor body is divided into multiple honeycomb-shaped chambers by multiple baffles 7. The central honeycomb chamber contains metal hydrides, and the honeycomb chambers from the center outwards are alternately filled with phase change materials and hydrogen storage materials. Specifically, the second layer of honeycomb chambers contains phase change materials, the third layer contains metal hydrides, and the fourth layer contains phase change materials.

[0048] In this embodiment, each compartment is alternately filled with phase change material and hydrogen storage material, allowing the reaction heat released during the metal hydride hydrogen storage process to be rapidly transferred to the phase change material. The honeycomb structure provides a larger heat transfer area and a more uniform heat transfer effect, which helps to achieve efficient heat management and hydrogen storage performance.

[0049] Considering the impact of buoyancy-driven natural convection on the heat transfer process during the endothermic melting of phase change materials (PCMs), the presence of natural convection causes hot fluids to rise and cold fluids to sink. Therefore, the temperature of the upper PCM is significantly higher than that of the lower PCM, which hinders the uniform reaction of metal hydrides and thus reduces hydrogen storage efficiency. To address this issue, in some specific embodiments, PCMs are arranged in a stepped, partitioned manner, such as... Figure 4 As shown, within the region containing the phase change material, the phase change material with the highest phase change temperature is placed in the region dominated by natural convection. Conversely, within the region containing the phase change material, the phase change material with the lowest phase change temperature is placed in the region dominated by thermal conductivity.

[0050] Example 2:

[0051] With the same mass of metal hydride and phase change material as in Example 1, each phase change material zone is uniformly separated along the axial direction by four partitions to form four chambers, creating independent thermal management areas. Four phase change materials with different phase change temperatures and latent heat values ​​are uniformly filled along the axial direction from bottom to top: paraffin RT29, LiNO3·3H2O, paraffin RT35, and paraffin RT38. The metal hydride is LaNi5, the initial temperature is 293.15 K, the initial pressure is the equilibrium pressure corresponding to the initial temperature (0.143 MPa), the initial density of the metal hydride is the density in the unabsorbed hydrogen state, and the hydrogen supply pressure is 0.8 MPa. At this point, a large amount of reaction heat transferred via the metal hydride is transferred to the phase change materials placed in the four chambers. Due to the axially stepped arrangement of the phase change materials, RT29 at the bottom absorbs heat and melts first. As the temperature rises, the heat is gradually transferred to the middle and upper parts, where LiNO3·3H2O, RT35, and RT38 melt in sequence. This prevents localized overheating in the upper region due to buoyancy and ensures a uniform temperature distribution throughout the reactor. This stepped arrangement effectively utilizes the different phase change temperatures and latent heat values ​​of the phase change materials. By managing heat in zones, the reaction heat released during hydrogen storage is gradually absorbed, achieving efficient thermal management and significantly improving hydrogen storage efficiency.

[0052] This invention significantly optimizes heat management and improves hydrogen storage efficiency by introducing a solid-state hydrogen storage reactor based on a partitioned and tiered arrangement of phase change materials and metal hydrides. Compared with traditional hydrogen storage reactors, the alternating arrangement increases the heat transfer area and reduces the heat conduction distance, thereby greatly shortening the hydrogen storage time and improving the uniformity of temperature distribution.

[0053] Moreover, the tiered arrangement, by rationally configuring phase change materials with different phase change temperatures and latent heat values, prevents local overheating and ensures uniform temperature distribution inside the reactor. This not only improves the hydrogen storage rate and efficiency and reduces energy consumption, but also has great application potential and economic benefits, and is suitable for multiple fields such as mobile hydrogen storage, stationary hydrogen storage and industrial hydrogen storage.

[0054] In one or more embodiments, an energy supply device is also provided, comprising a hydrogen storage reactor based on a partitioned arrangement of phase change materials and metal hydrides as described above. This energy supply device can be applied to mobile hydrogen storage applications, such as fuel cell vehicles and drones, which require efficient and lightweight hydrogen storage systems. By optimizing thermal management, it improves energy utilization and extends the device's operating time, effectively solving the problems of high energy consumption and low efficiency in traditional hydrogen storage systems. It also enhances the performance and reliability of mobile devices, meeting the demands of modern mobile hydrogen storage technology for high efficiency, portability, and high energy density.

[0055] 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 reactor based on a partitioned arrangement of phase change materials and metal hydrides, characterized in that, The reactor includes a hydrogen storage reactor body, a hydrogen inlet channel, an expansion zone, a baffle, and an outer shell. The expansion zone is used to temporarily store and uniformly distribute the incoming hydrogen, while mitigating pressure fluctuations and the volume expansion of the metal hydride. The baffle divides the hydrogen storage reactor body into several regions. In these regions, phase change materials and metal hydrides are arranged alternately, so that the reaction heat released by the metal hydride during hydrogen storage is transferred to the phase change materials in adjacent regions through the two side walls of its respective region, thereby increasing the effective heat transfer area. The baffle plate divides the hydrogen storage reactor body in a honeycomb-shaped partitioning manner, forming multiple honeycomb-shaped chambers; The central honeycomb chamber contains metal hydride, and the honeycomb chambers from the center outwards are alternately filled with phase change material and hydrogen storage material. The partition plate divides the hydrogen storage reactor body in a fan-shaped partitioning manner; Phase change materials with different phase change temperatures are arranged in a tiered manner within the region containing the phase change material.

2. The hydrogen storage reactor based on the partitioned arrangement of phase change materials and metal hydrides as described in claim 1, characterized in that, The partition plate divides the hydrogen storage reactor body into triangular sections.

3. The hydrogen storage reactor based on the partitioned arrangement of phase change materials and metal hydrides as described in claim 1, characterized in that, The partition plate divides the hydrogen storage reactor body into regular polygonal sections.

4. The hydrogen storage reactor based on the partitioned arrangement of phase change materials and metal hydrides as described in claim 1 is characterized in that, Within the region where the phase change material is located, the phase change material with the highest phase change temperature is placed in the area dominated by natural convection.

5. The hydrogen storage reactor based on the partitioned arrangement of phase change materials and metal hydrides as described in claim 1, characterized in that, Within the region containing the phase change material, the phase change material with the lowest phase change temperature should be placed in the area dominated by thermal conductivity.

6. A power supply device, characterized in that, Includes a hydrogen storage reactor based on a partitioned arrangement of phase change materials and metal hydrides as described in any one of claims 1-5.

Images