A method for preparing a high mass transfer and high heat transfer type multidimensional powder hydrogen storage material

Abstract

This invention provides a method for preparing a multidimensional powdered hydrogen storage material with high mass transfer and high heat transfer, relating to the field of hydrogen storage material preparation technology. The method includes the following steps: selecting hydrogen storage material particles as the initial hydrogen storage material, selecting a metal mesh or foam material as a two-dimensional or three-dimensional framework, and adding a pore-forming agent to an organic solvent containing a high-temperature resistant resin to obtain a binder solution; under the assistance of the binder solution and ultrasonic vibration, uniformly filling the pores of the framework with the hydrogen storage material particles; and heating and curing the filled material under an argon atmosphere to obtain the multidimensional powdered hydrogen storage material with high mass transfer and high heat transfer. Compared to the initial powdered hydrogen storage material, the multidimensional powdered hydrogen storage material prepared by this invention has a thermal conductivity increased by more than 7 times, the time to absorb hydrogen to 90% saturation capacity is shortened by 22% to 54% compared to traditional processes, and the effective hydrogen storage capacity, hydrogen absorption and desorption kinetics, and cycle life of the initial powdered hydrogen storage material are significantly improved.

Description

Technical Field

[0001] This invention relates to the field of hydrogen storage material preparation technology, and in particular to a method for preparing a multidimensional powdered hydrogen storage material with high mass transfer and high heat transfer. Background Technology

[0002] Hydrogen energy, as a clean, efficient, and sustainable secondary energy source, has become an important component of the future energy system. In the hydrogen energy industry chain, the safe and efficient storage of hydrogen is a crucial link connecting production and application. While existing high-pressure gaseous hydrogen storage technology is relatively mature and widely used, the compression process consumes 15% to 25% of the chemical energy contained in the hydrogen, and high-pressure containers pose safety risks due to hydrogen embrittlement or leakage. Although liquid hydrogen storage has a high volumetric energy density, its liquefaction and maintenance of cryogenic environments result in high energy consumption and cost, limiting its large-scale application.

[0003] In contrast, solid-state hydrogen storage technology, with its advantages of high volumetric hydrogen storage density, low operating pressure, and good safety, has become a promising hydrogen storage method. This technology stores hydrogen in the lattice of metal or alloy powders through a chemical adsorption mechanism, effectively avoiding the safety risks of high-pressure gaseous hydrogen storage. Some metal hydride materials (such as magnesium-based hydrogen storage materials) can achieve volumetric hydrogen storage densities that reach or even exceed those of liquid hydrogen, without the need for complex cryogenic maintenance systems. However, although bulk metal hydrogen storage materials typically possess high thermal conductivity (e.g., the thermal conductivity of bulk magnesium hydrogen storage materials is approximately 156 W / (m·K), and that of bulk TiFe hydrogen storage materials is above 10 W / (m·K), in practical applications, hydrogen storage materials are mostly used in powder form. Powdered hydrogen storage materials are limited by the contact points between particles and tiny gas gaps, resulting in extremely high contact thermal resistance. Typical hydrogen storage materials such as Mg, LaNi5, and TiFe have extremely low effective thermal conductivity in their powdered state, typically only 0.1 W / (m·K) to 1.0 W / (m·K). Furthermore, metal hydrides undergo significant volume changes during hydrogen absorption and desorption cycles (expansion / contraction rates are typically between 15% and 25%), and this drastic volume effect further pulverizes the powdered hydrogen storage materials. The pulverized powder is highly prone to agglomeration in a free-stacking state, reducing porosity and blocking hydrogen diffusion channels. Consequently, heat transfer performance deteriorates further, making localized heat transfer difficult within the powdered hydrogen storage material, thus severely limiting its hydrogen absorption and desorption kinetics and cycle life.

[0004] To address these issues, existing technologies typically employ high-pressure pressing to compress hydrogen storage material powder with high thermal conductivity additives (such as expanded graphite, aluminum powder, and copper powder) into high-density composite hydrogen storage blocks (Journal of Dalian University of Technology, 2024, 64(5):441-446). While this method can improve the overall thermal conductivity of the material, it has significant drawbacks: Firstly, the high-intensity mechanical pressing reduces the porosity between powder particles, leading to excessive densification that blocks the microscopic diffusion channels of hydrogen, resulting in a significant decrease in material permeability and creating a technical contradiction of "high thermal conductivity and low mass transfer." Secondly, the additional stress generated during the pressing process further exacerbates the stress caused by volume expansion / contraction during repeated hydrogen absorption and desorption of the hydrogen storage material, promoting structural disintegration and collapse of the hydrogen storage material, ultimately leading to irreversible degradation of hydrogen storage performance and a severe shortening of cycle life.

[0005] This invention proposes a method for preparing multidimensional powdered hydrogen storage materials with high mass transfer and high heat transfer, which effectively improves thermal conductivity while maintaining unobstructed hydrogen diffusion channels. This preparation method has significant scientific and application value for improving the hydrogen absorption and desorption kinetics of powdered hydrogen storage materials, extending their cycle life, and increasing their effective hydrogen storage capacity. Summary of the Invention

[0006] This invention proposes a method for preparing a multidimensional powdered hydrogen storage material with high mass transfer and high heat transfer, aiming to solve the problems of low thermal conductivity and poor mass transfer rate of existing powdered hydrogen storage materials in practical applications. The specific technical solution is as follows: A method for preparing a multidimensional powdered hydrogen storage material with high mass transfer and high heat transfer includes the following steps: S1. Select hydrogen storage material particles as the initial hydrogen storage material, select metal mesh or foam material as a two-dimensional or three-dimensional skeleton, and add pore-forming agent to an organic solvent containing high-temperature resistant resin to obtain a binder solution. S2. With the aid of binder solution and ultrasonic vibration, the hydrogen storage material particles are uniformly filled into the pores of the skeleton; S3. Under the protection of argon atmosphere, the filled material is heated and cured to solidify the organic solution containing high temperature resistant resin to form a continuous adhesive layer. At the same time, the pore-forming agent decomposes in the continuous adhesive layer to form gas diffusion channels, and finally a multidimensional powder hydrogen storage material with high mass transfer and high heat transfer is obtained.

[0007] Optionally, in step S1, the hydrogen storage material particles are selected from one or more of magnesium-based, rare earth-based, zirconium-based, titanium-based metal hydrides and vanadium-based solid solution solid hydrogen storage materials, and their particle size ranges from 45 mesh to 200 mesh.

[0008] Optionally, in step S1, the metal mesh is selected from stainless steel mesh, nickel mesh, or copper mesh, with a mesh count ranging from 30 to 150 mesh; the foam material is selected from nickel foam, copper foam, or foam, with a pore density ranging from 30 to 120 PPI. This invention utilizes the excellent thermal conductivity and structural connectivity of the above materials to construct a two-dimensional or three-dimensional mass-heat transfer network. When the mesh count of the metal mesh or the pore density of the foam material is lower than 30 mesh or 30 PPI, the pore size of the framework is too large, the heat conduction path is prolonged, and the thermal resistance of the system increases; when the mesh count of the metal mesh or the pore density of the foam material is higher than 150 mesh or 120 PPI, the pore size of the framework is too small, which is not conducive to the filling of powdered hydrogen storage materials, thereby reducing the effective hydrogen storage capacity.

[0009] Optionally, in step S1, the organic solvent containing the high-temperature resistant resin serves as a dispersion medium, and the high-temperature resistant resin serves as a binder. The organic solvent is selected from acetone, toluene, or xylene. The high-temperature resistant resin is selected from modified phenolic resin, epoxy phenolic composite resin, or silicone resin, and the high-temperature resistant resin accounts for 20% to 25% of the total mass of the organic solvent and the high-temperature resistant resin. The pore-forming agent is selected from one or both of sodium bicarbonate and polymethyl methacrylate (PMMA), and the pore-forming agent accounts for 40% to 80% of the total mass of the high-temperature resistant resin, organic solvent, and pore-forming agent.

[0010] Optionally, in step S2, one of the following two methods is used to fill the framework with the hydrogen storage material particles: Method 1: Disperse the hydrogen storage material particles in the binder solution to obtain a mixed slurry, and then fill the mixed slurry into the skeleton; Method 2: First, immerse the skeleton in the binder solution, and then fill the hydrogen storage material particles into the impregnated skeleton.

[0011] Optionally, in step S2, the frequency of the ultrasonic vibration is 15 kHz to 100 kHz, and the ultrasonic treatment time is 10 minutes to 60 minutes.

[0012] Optionally, in step S2, the hydrogen storage material particles are uniformly filled in the above-mentioned skeleton, and the mass filling rate is greater than 75%.

[0013] Optionally, in step S3, the heat curing is carried out under an argon atmosphere of 0.1 MPa to 1 MPa, the curing temperature is 300℃ to 450℃, the holding time is 0.5 h to 1 h, and the heating rate is 3℃ / min to 6℃ / min. Under the heating conditions within the above parameter range, the high-temperature resistant resin can be fully cured, while the pore-forming agent is completely decomposed and gas diffusion channels are formed. Moreover, this temperature range will not adversely affect the activity of the metal hydrogen storage material.

[0014] The present invention also provides a hydrogen storage material prepared by the method, and the application of the hydrogen storage material in the field of solid-state hydrogen storage.

[0015] In the preparation method of this invention, the content of high-temperature resistant resin in the organic solvent has a significant impact on the structural stability of the powdered hydrogen storage material particles: if the content of high-temperature resistant resin in the organic solvent is too low, the powdered hydrogen storage material particles mainly form "point bonding" with the two-dimensional or three-dimensional skeleton, resulting in insufficient overall bonding strength and easy collapse; if the content of high-temperature resistant resin in the organic solvent is too high, the powdered hydrogen storage material particles will be continuously coated with high-temperature resistant resin, which is beneficial to improving structural stability, but will significantly block the hydrogen diffusion channels, leading to a decrease in mass transfer performance.

[0016] To address the aforementioned contradictions, this invention introduces a pore-forming agent and utilizes its in-situ decomposition during the heating and curing process to generate gas diffusion channels in-situ within the formed resin adhesive layer, thereby fully ensuring the high thermal and mass transfer properties of the powdered hydrogen storage material particles.

[0017] Furthermore, in the preparation method of this invention, there is a precise matching relationship between the decomposition temperature of the pore-forming agent and the curing temperature of the high-temperature resistant resin. When sodium bicarbonate is selected as the pore-forming agent, its main decomposition temperature range (50~270℃) is lower than the curing temperature of the high-temperature resistant resin (300~450℃). Therefore, during the stage before the high-temperature resistant resin is fully cured, the CO2 gas generated by the decomposition of sodium bicarbonate can expand and establish pore channels in the semi-cured high-temperature resistant resin. When polymethyl methacrylate is selected as the pore-forming agent, its decomposition temperature (200~350℃) partially overlaps with the curing temperature of the high-temperature resistant resin, and it gradually decomposes and vaporizes during the heating process, leaving continuous micropores in situ in the high-temperature resistant resin matrix. Both of the above pore-forming methods can effectively construct gas diffusion channels.

[0018] In the preparation method of this invention, the ratio between the amount of high-temperature resistant resin organic solvent and the amount of pore-forming agent is a key parameter for balancing heat transfer and mass transfer performance: when the proportion of the pore-forming agent to the total mass of the high-temperature resistant resin organic solvent and pore-forming agent is less than 40%, the high-temperature resistant resin is relatively excessive, which easily forms a dense and continuous coating layer, limiting the hydrogen diffusion channels and restricting the mass transfer performance; when the mass proportion of the pore-forming agent is controlled within the range of 40-80%, continuous heat conduction can be achieved between the powder hydrogen storage material particles and between the particles and the two-dimensional or three-dimensional skeleton, while the pore-forming agent decomposes to form sufficient gas diffusion channels with an open porosity greater than 50%, achieving excellent synergistic performance of mass transfer and heat transfer; when the mass proportion of the pore-forming agent exceeds 80%, the content of high-temperature resistant resin in the system is insufficient, making it difficult to form an effective bonding structure, and the overall mechanical stability and service life of the material decrease significantly.

[0019] In summary, the preparation method provided by this invention, through the synergistic effect of "two-dimensional or three-dimensional skeleton support + high-temperature resistant resin flexible bonding + pore-forming agent in-situ pore-forming", produces a multidimensional powder hydrogen storage material with high mass transfer and high heat transfer performance.

[0020] From the perspective of individual technical elements, powdered hydrogen storage material particles, metal mesh / foam material skeletons, organic solvents containing high-temperature resistant resins, and pore-forming agents are all known materials in this field. However, this invention creatively combines these elements in a specific way to form a novel preparation method that resolves the technical contradiction between "high heat transfer and high mass transfer" in hydrogen storage materials. The technical solution of this invention is not a simple superposition of known technical elements, but rather includes systematic technical innovation and parameter optimization. Through extensive experimental research, this invention has achieved breakthroughs in the following key technical nodes: First, the optimal structural parameters of the two-dimensional / three-dimensional matrix skeleton (metal mesh number 30-150 mesh, foam material pore density 30 PPI to 120 PPI) were determined. This parameter range is based on the inherent balance between heat transfer efficiency and material filling rate, which solves the contradiction between the thermal conductivity of the skeleton and the effective loading of hydrogen storage material.

[0021] Secondly, the optimal mass ratio (20%~25%) of the high-temperature resistant resin in the organic solvent was determined, and its matching relationship with the particle size (45 mesh~200 mesh) and mass filling rate (>75%) of the hydrogen storage material was clarified. This parameter combination overcomes the technical contradiction between insufficient structural strength caused by "point bonding" and hydrogen channel blockage caused by "continuous coating", and achieves synergistic optimization of bonding strength and gas diffusion channels.

[0022] Third, innovatively, pore-forming agents (sodium bicarbonate and polymethyl methacrylate) were introduced and their optimal addition amount in the mixture was determined (40%~80%). By precisely matching the relationship between the decomposition temperature of the pore-forming agent and the curing temperature of the resin, gas diffusion channels (open porosity >50%) were constructed in situ in the cured adhesive layer, fundamentally solving the contradiction between high heat transfer and high mass transfer performance.

[0023] Finally, the system optimized the curing process parameters (curing temperature 300~450℃, holding time 0.5 h~1 h) to ensure that the high-temperature resistant resin is fully cured while promoting the complete decomposition of the pore-forming agent and forming an effective gas diffusion channel. Moreover, this temperature range will not have an adverse effect on the activity of the hydrogen storage material.

[0024] The determination of the above technical parameters is based on an in-depth analysis of the intrinsic relationship between heat transfer, mass transfer, and mechanical stability. Through extensive experimental verification, the optimal range of multiple technical parameters was precisely determined, ultimately resulting in the preparation of a multidimensional powdered hydrogen storage material with both high thermal conductivity and high mass transfer. This technical route has not been reported in existing hydrogen storage material modification technologies, demonstrating the innovation and non-obviousness of this invention. Due to the adoption of the above technical solution, the technical progress achieved by this invention compared to existing technologies is as follows: 1. The powdered hydrogen storage material prepared by this invention has a dual structure design of macroscopic two-dimensional or three-dimensional skeleton and microscopic gas diffusion channel. While ensuring high heat transfer performance (the effective thermal conductivity is increased by more than 7 times), it significantly improves hydrogen mass transfer performance (the time to absorb hydrogen to 90% saturation capacity is shortened by 22% to 54% compared with the traditional process).

[0025] 2. Compared with traditional mechanical pressing processes, this invention utilizes the synergistic effect of a high-temperature resistant resin adhesive layer and a two-dimensional or three-dimensional skeleton to avoid the additional stress introduced by high-pressure pressing. After 100 cycles, the material retains 96.0% to 99.9% of its capacity, significantly extending its service life.

[0026] 3. This invention utilizes ultrasonic-assisted filling technology to effectively suppress the agglomeration of fine powders and promote the uniform filling of hydrogen storage powder particles within a two-dimensional or three-dimensional framework. This results in a hydrogen storage powder particle mass filling rate of more than 75%, and the maximum hydrogen storage capacity is increased by 30.0% to 75.0% compared to traditional pressing processes.

[0027] 4. The preparation method of this invention has a simple process flow and controllable parameters. The raw materials used are widely available and inexpensive. It is applicable to various types of solid hydrogen storage materials such as magnesium-based, rare earth-based, zirconium-based, titanium-based metal hydrides and vanadium-based solid solutions, and has broad prospects for large-scale application. Attached Figure Description

[0028] To more clearly illustrate the technical solutions in the embodiments of the present invention, the accompanying drawings used in the description of the embodiments will be briefly introduced below. Obviously, the accompanying drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0029] Figure 1 This is a SEM microstructure image of an AB5-type powdered hydrogen storage material with high mass transfer and high heat transfer prepared in Example 1 of the present invention.

[0030] Figure 2 This is a SEM microstructure image of an AB5-type powdered hydrogen storage material with high mass transfer and high heat transfer prepared in Example 4 of the present invention.

[0031] Figure 3 This is a SEM microstructure image of the AB5 type powdered hydrogen storage material prepared in Comparative Example 3 of this invention.

[0032] Figure 4 This is a comparison of the hydrogen absorption kinetics curves of the powdered hydrogen storage materials prepared in Example 1 and Comparative Example 3 of the present invention.

[0033] Figure 5 The hydrogen absorption and desorption cycle capacity retention curve of an AB5 type powdered hydrogen storage material with high mass transfer and high heat transfer prepared in Example 1 of the present invention at 25°C. Detailed Implementation

[0034] To make the technical problems, technical solutions and advantages of the present invention clearer, a detailed description will be given below in conjunction with the accompanying drawings and specific embodiments.

[0035] In this invention, unless otherwise specified, all equipment and raw materials are commercially available or commonly used in the industry. The methods described in the following embodiments are conventional methods in the art, unless otherwise specified.

[0036] Example 1

[0037] A method for preparing AB5-type LaNi5 multidimensional powder hydrogen storage material with high mass transfer and high heat transfer includes the following steps: (1) Select nickel foam with a pore density of 30 PPI as a three-dimensional skeleton, clean it with anhydrous ethanol by ultrasonic cleaning and then dry it for later use. (2) Preparation of adhesive solution: Weigh 20 g of toluene solution containing silicone resin (mass fraction of 25%) (5 g of silicone resin and 15 g of toluene), add 50 g of sodium bicarbonate to the above solution and mix evenly to obtain adhesive solution. The mass of pore-forming agent accounts for 71.4% of the total mass of adhesive solution; (3) Preparation of mixed slurry: Add 28 g of LaNi5 hydrogen storage alloy powder with a particle size of 80-100 mesh to the binder solution obtained in step (2), and stir evenly to obtain mixed slurry; (4) Immerse the nickel foam prepared in step (1) into the mixed slurry prepared in step (3) and treat it for 20 minutes under the assistance of ultrasonic waves at a frequency of 50 kHz, so that the LaNi5 hydrogen storage alloy powder is uniformly filled and adhered to the pores of the nickel foam. (5) The nickel foam filled with LaNi5 hydrogen storage alloy powder was placed in a sealed container, and argon gas at 0.5 MPa was introduced for protection. The temperature was increased to 380°C at a heating rate of 5°C / min, and held at that temperature for 0.5 hours for curing. During this process, the toluene solution containing silicone resin cured to form a continuous adhesive layer, and sodium bicarbonate decomposed upon heating, generating gas diffusion channels in situ within the continuous adhesive layer. After curing, the material was naturally cooled to room temperature to obtain the LaNi5 multidimensional powder hydrogen storage material with high mass transfer and high heat transfer. (6) Performance test results: The morphology of the hydrogen storage material is as follows Figure 1 As shown, the material surface is relatively smooth and dense. Hydrogen storage alloy powder is uniformly filled into the pores of the three-dimensional nickel foam skeleton. The powder particles are tightly connected by a continuous high-temperature resistant silicone resin bonding layer. A few white bright spots are visible, representing the exposed metal skeleton. The pores are uniformly distributed and of moderate quantity, resulting in a compact overall structure. This ensures both a high mass filling rate and the formation of adequate gas diffusion channels, thus achieving a good balance between mass and heat transfer performance. The initial hydrogen storage material mass filling rate reaches 78.3%, the open porosity is 71.3%, the effective thermal conductivity is 12.3 W / (m·K), and the maximum hydrogen storage capacity is 1.48 wt.%. In terms of hydrogen storage kinetics, the time required to absorb hydrogen to 90% saturation capacity is 4.3 minutes. The hydrogen absorption / desorption cycle capacity retention curve of the hydrogen storage material at 25℃ is shown in the figure. Figure 5 As shown, after 100 hydrogen absorption and desorption cycles, the hydrogen storage capacity of the material only slowly decreased from the initial 1.46 wt.% to 1.443 wt.%, with a capacity retention rate of 98.9%, demonstrating excellent cycle stability.

[0038] Example 2

[0039] A type A2B7 La with high mass transfer and high heat transfer 0.8 Mg 0.2 Ni 3.5 The preparation method of powdered hydrogen storage materials includes the following steps: (1) Select copper foam with a pore density of 50 PPI as a three-dimensional skeleton, clean it with anhydrous ethanol by ultrasonic cleaning and then dry it for later use. (2) Preparation of adhesive solution: Weigh 25 g of xylene solution containing modified phenolic resin (mass fraction of 23%) (of which 5.75 g of modified phenolic resin and 19.25 g of xylene), add 35 g of polymethyl methacrylate to the above solution and mix evenly to obtain adhesive solution. The mass of pore-forming agent accounts for 58.3% of the total mass of adhesive solution; (3) Preparation of mixed slurry: Add La with a particle size of 100-150 mesh to the binder solution obtained in step (2). 0.8 Mg 0.2 Ni 3.530 g of hydrogen storage alloy powder was stirred evenly to obtain a mixed slurry. (4) Immerse the copper foam prepared in step (1) into the mixed slurry obtained in step (3), and treat it for 15 minutes under ultrasonic assistance at a frequency of 40 kHz, so that La 0.8 Mg 0.2 Ni 3.5 Hydrogen storage alloy powder is uniformly filled and adhered to the pores of copper foam; (5) Fill with La 0.8 Mg 0.2 Ni 3.5 Copper foam, a powdered hydrogen storage material, was placed in a sealed container and protected with argon gas at 0.8 MPa. The temperature was increased to 430°C at a rate of 6°C / min and held for 1 hour for curing. During this process, a xylene solution containing modified phenolic resin cured to form a continuous adhesive layer. Polymethyl methacrylate (PMMA) decomposed upon heating, generating in-situ gas diffusion channels within the continuous adhesive layer. After curing, the material was allowed to cool naturally to room temperature, yielding the La233 hydrogen storage material with high mass transfer and high heat transfer properties. 0.8 Mg 0.2 Ni 3.5 Multidimensional powder hydrogen storage material. (6) Performance test results: The initial hydrogen storage material mass filling rate was 76.8%, the porosity was 64.7%, the effective thermal conductivity was 18.6 W / (m·K), and the maximum hydrogen storage capacity was 1.52 wt.%. The time to absorb hydrogen to 90% saturation capacity was 4.2 minutes, and the capacity retention rate was 98.6% after 100 cycles.

[0040] Example 3

[0041] A TiFe system with high mass transfer and high heat transfer 0.95 Mn 0.05 The preparation method of powdered hydrogen storage materials includes the following steps: (1) Select 50-mesh stainless steel mesh as a two-dimensional skeleton, clean it with anhydrous ethanol by ultrasonic cleaning and then dry it for later use. (2) Preparation of adhesive solution: Weigh 20 g of toluene solution containing silicone resin (mass fraction of 20%) (of which silicone resin is 4 g and xylene is 16 g), add 30 g of a mixture of sodium bicarbonate and polymethyl methacrylate (mass ratio of sodium bicarbonate to polymethyl methacrylate is 1:1) to the above solution and mix evenly to obtain adhesive solution. The mass of pore-forming agent accounts for 60% of the total mass of adhesive solution; (3) Preparation of mixed slurry: Add TiFe with a particle size of 80-100 mesh to the binder solution obtained in step (2). 0.95 Mn 0.05 25 g of hydrogen storage alloy powder was stirred evenly to obtain a mixed slurry. (4) Immerse the stainless steel mesh prepared in step (1) into the mixed slurry obtained in step (3), and treat it for 20 minutes under ultrasonic assistance at a frequency of 60 kHz to allow the TiFe to precipitate. 0.95 Mn 0.05 Hydrogen storage alloy powder is uniformly filled and adhered to the pores of the stainless steel mesh. (5) The TiFe already filled 0.95 Mn 0.05 The stainless steel mesh of the powdered hydrogen storage material was placed in a sealed container, filled with argon gas at 0.4 MPa for protection, and heated to 380°C at a heating rate of 5°C / min, and held at that temperature for 0.5 hours for curing. During this process, the silicone resin-containing organic solution cured to form a continuous adhesive layer, and sodium bicarbonate and polymethyl methacrylate decomposed upon heating, generating gas diffusion channels in situ within the continuous adhesive layer. After curing, it was naturally cooled to room temperature to obtain the TiFe material with high mass transfer and high heat transfer properties. 0.95 Mn 0.05 Multidimensional powder hydrogen storage material. (6) Performance test results: The initial hydrogen storage material mass filling rate was 79.5%, the porosity was 66.3%, the effective thermal conductivity was 9.8 W / (m·K), and the maximum hydrogen storage capacity reached 1.75 wt.%. The time to absorb hydrogen to 90% saturation capacity was 4.5 minutes, and the capacity retention rate was 96.7% after 100 cycles.

[0042] Example 4

[0043] A method for preparing AB5-type LaNi5 multidimensional powder hydrogen storage material with high mass transfer and high heat transfer includes the following steps: (1) Select foam with a pore density of 45 PPI as a three-dimensional skeleton, ultrasonically clean it with anhydrous ethanol and then dry it for later use. (2) Preparation of adhesive solution: Weigh 20 g of acetone solution containing epoxy phenolic composite resin (mass fraction of 24%) (of which 4.8 g of epoxy phenolic composite resin and 15.2 g of acetone are added), add 14 g of polymethyl methacrylate to the above solution and mix evenly to obtain adhesive solution. The mass of pore-forming agent accounts for 41.2% of the total mass of adhesive solution. (3) Immerse the foam prepared in step (1) into the adhesive solution prepared in step (2); (4) Weigh 10 g of LaNi5 powder hydrogen storage material with a particle size of 80-150 mesh, put the foam soaked in the binder solution prepared in step (3) into the above powder hydrogen storage material, and treat it for 10 minutes under the assistance of ultrasonic waves at a frequency of 30 kHz, so that the LaNi5 hydrogen storage alloy powder is uniformly filled and adhered to the pores of the foam. (5) Place the foam filled with LaNi5 powder hydrogen storage material in a sealed container, fill it with argon gas at 1.0 MPa for protection, and heat it to 300°C at a heating rate of 3°C / min, holding it at that temperature for 0.5 hours for curing. During this process, the acetone solution containing epoxy phenolic composite resin cures to form a continuous adhesive layer, and polymethyl methacrylate decomposes upon heating, generating gas diffusion channels in situ within the continuous adhesive layer. After curing, allow it to cool naturally to room temperature to obtain the LaNi5 multidimensional powder hydrogen storage material with high mass transfer and high heat transfer. (6) Performance test results: The initial hydrogen storage material mass filling rate was 71.2%, the open porosity was 53.6%, the effective thermal conductivity was 7.2 W / (m·K), and the maximum hydrogen storage capacity was 1.46 wt.%. The time to absorb hydrogen to 90% saturation capacity was 5.1 minutes, and the capacity retention rate after 100 cycles was 97.1%. The morphology of the hydrogen storage material is as follows: Figure 2 As shown, the material uses foam as a three-dimensional skeleton, exhibiting a distinct porous and loose structure. Numerous irregularly shaped pores are clearly visible, and the connections between particles are relatively loose. The three-dimensional skeleton structure is more prominent, with large pore sizes and good connectivity, which is conducive to the rapid diffusion of hydrogen.

[0044] Example 5

[0045] A method for preparing a magnesium-based MgH2 powder hydrogen storage material with high mass transfer and high heat transfer includes the following steps: (1) Select copper foam with a pore density of 70 PPI as a three-dimensional skeleton, clean it with anhydrous ethanol by ultrasonic cleaning and then dry it for later use. (2) Preparation of adhesive solution: Weigh 18 g of acetone solution containing modified phenolic resin (mass fraction of 22%) (of which 3.96 g of modified phenolic resin and 14.04 g of acetone are added, and 22 g of polymethyl methacrylate is added to the above solution and mixed evenly to obtain adhesive solution. The mass of pore-forming agent accounts for 55% of the total mass of adhesive solution. (3) Preparation of mixed slurry: Add 20 g of MgH2 hydrogen storage alloy powder with a particle size of 150-200 mesh to the binder solution obtained in step (2), and stir evenly to obtain mixed slurry; (4) Immerse the foamed copper prepared in step (1) into the mixed slurry prepared in step (3) and treat it for 15 minutes under the assistance of ultrasonic waves at a frequency of 80 kHz, so that the MgH2 hydrogen storage alloy powder is uniformly filled and adhered to the pores of the foamed copper. (5) The foamed copper filled with MgH2 powder hydrogen storage material was placed in a sealed container, and argon gas at 1.0 MPa was introduced for protection. The temperature was increased to 390°C at a rate of 6°C / min, and held at that temperature for 0.8 hours for curing. During this process, the acetone solution containing modified phenolic resin cured to form a continuous adhesive layer, and polymethyl methacrylate decomposed upon heating, generating gas diffusion channels in situ within the continuous adhesive layer. After curing, the mixture was allowed to cool naturally to room temperature to obtain the MgH2 multidimensional powder hydrogen storage material with high mass transfer and high thermal transfer properties. (6) Performance test results: The initial hydrogen storage material mass filling rate was 77.6%, the porosity was 63.2%, the effective thermal conductivity was 10.3 W / (m·K), and the maximum hydrogen storage capacity was 6.81 wt.%. The time to absorb hydrogen to 90% saturation capacity was 4.8 minutes, and the capacity retention rate was 97.6% after 100 cycles.

[0046] Example 6

[0047] An AB2 type Ti with high mass transfer and high heat transfer properties 0.8 Zr 0.2 The preparation method of Mn2 powder hydrogen storage material includes the following steps: (1) Select a 70-mesh nickel mesh as a two-dimensional skeleton, clean it with anhydrous ethanol by ultrasonic cleaning and then dry it for later use. (2) Preparation of adhesive solution: Weigh 15 g of acetone solution containing epoxy phenolic composite resin (mass fraction of 24%) (of which epoxy phenolic composite resin is 3.6 g and acetone is 11.4 g), add 28 g of polymethyl methacrylate to the above solution and mix evenly to obtain adhesive solution. The mass of pore-forming agent accounts for 65.1% of the total mass of adhesive solution; (3) Preparation of mixed slurry: Add Ti with a particle size of 100-120 mesh to the binder solution obtained in step (2). 0.8 Zr 0.2 25 g of Mn2 hydrogen storage alloy powder was stirred evenly to obtain a mixed slurry. (4) Immerse the nickel mesh prepared in step (1) into the mixed slurry obtained in step (3), and treat it for 10 minutes under ultrasonic assistance at a frequency of 70 kHz, so that Ti 0.8 Zr 0.2 Mn2 hydrogen storage alloy powder is uniformly filled and adhered to the pores of the nickel mesh; (5) The Ti already filled 0.8 Zr 0.2The nickel mesh of the Mn2 powder hydrogen storage material was placed in a sealed container and protected with argon gas at 0.3 MPa. The temperature was increased to 330°C at a rate of 5°C / min and held for 0.5 hours for curing. During this process, the acetone solution containing epoxy phenolic resin cured to form a continuous adhesive layer. Polymethyl methacrylate decomposed upon heating, generating in-situ gas diffusion channels within the continuous adhesive layer. After curing, the material was allowed to cool naturally to room temperature, yielding the Ti material with high mass transfer and high heat transfer properties. 0.8 Zr 0.2 Mn2 multidimensional powder hydrogen storage material. (6) Performance test results: The initial hydrogen storage material mass filling rate was 80.1%, the porosity was 68.5%, the effective thermal conductivity was 11.5 W / (m·K), and the maximum hydrogen storage capacity was 1.83 wt.%. The time to absorb hydrogen to 90% saturation capacity was 4.6 minutes, and the capacity retention rate was 98.2% after 100 cycles.

[0048] Example 7

[0049] A TiFe system with high mass transfer and high heat transfer 0.9 Mn 0.1 The preparation method of powdered hydrogen storage materials includes the following steps: (1) Select a 90-mesh copper mesh as a two-dimensional skeleton, clean it with anhydrous ethanol by ultrasonic cleaning and then dry it for later use. (2) Preparation of adhesive solution: Weigh 24g of toluene solution containing silicone resin (mass fraction of 20%) (of which silicone resin is 4.8g and toluene is 19.2g), add 36g of sodium bicarbonate and polymethyl methacrylate (mass ratio of sodium bicarbonate to polymethyl methacrylate is 2:1) to the above solution and mix evenly to obtain adhesive solution. The mass of pore-forming agent accounts for 60% of the total mass of adhesive solution; (3) Preparation of mixed slurry: Add TiFe with a particle size of 80-150 mesh to the binder solution obtained in step (2). 0.9 Mn 0.1 32 g of hydrogen storage alloy powder was stirred evenly to obtain a mixed slurry. (4) Immerse the copper mesh prepared in step (1) into the mixed slurry obtained in step (3), and treat it for 20 minutes under ultrasonic assistance at a frequency of 80 kHz, so that TiFe 0.9 Mn 0.1 Hydrogen storage alloy powder is uniformly filled and adhered to the pores of the copper mesh; (5) The TiFe already filled 0.9 Mn 0.1A copper mesh containing powdered hydrogen storage material was placed in a sealed container and protected with argon gas at 0.7 MPa. The temperature was increased to 400°C at a rate of 6°C / min and held at this temperature for 0.6 hours for curing. During this process, a toluene solution containing silicone resin cured to form a continuous adhesive layer. Sodium bicarbonate and polymethyl methacrylate decomposed upon heating, generating in-situ gas diffusion channels within the continuous adhesive layer. After curing, the material was allowed to cool naturally to room temperature, yielding the TiFe₂O₃ material with high mass and heat transfer properties. 0.9 Mn 0.1 Multidimensional powder hydrogen storage material. (6) Performance test results: The initial hydrogen storage material mass filling rate was 79.8%, the porosity was 67.9%, the effective thermal conductivity was 13.2 W / (m·K), and the maximum hydrogen storage capacity was 1.94 wt.%. The time to absorb hydrogen to 90% saturation capacity was only 4.0 minutes, which was the fastest among all examples, and the capacity retention rate was 98.5% after 100 cycles.

[0050] Comparative Example 1

[0051] To verify the advantages of this invention over traditional mechanical pressing technology, mechanically pressed hydrogen storage block samples were prepared: (1) Raw material preparation: 28 g of AB5 type LaNi5 powder hydrogen storage material with a particle size of 80~100 mesh was mechanically mixed with 10 wt.% of expanded graphite and stirred thoroughly; (2) The mixed powder is placed in a mold and cold-pressed at 600 MPa at room temperature. After holding the pressure for 5 minutes, it is demolded to obtain a high-density hydrogen storage block. (3) Performance test results: The material has a mass filling rate of 94.5%, but an extremely low porosity (<5.0%), an effective thermal conductivity of only 6.8 W / (m·K), and a maximum hydrogen storage capacity of 1.12 wt.%. It takes as long as 7.4 minutes to absorb hydrogen to 90% saturation capacity, and the capacity retention rate drops sharply to 81.2% after 100 cycles.

[0052] Comparative Example 2

[0053] To verify the role of pore-forming agents in constructing gas diffusion channels, a control sample without pore-forming agents was prepared: (1) Select nickel foam with a pore density of 30 PPI as a three-dimensional skeleton, clean it with anhydrous ethanol by ultrasonic cleaning and then dry it for later use. (2) Preparation of adhesive solution: Weigh 20 g of toluene solution containing silicone resin (mass fraction of 20%) (of which silicone resin is 4 g and toluene is 16 g). (3) Preparation of mixed slurry: Add 28 g of AB5 type LaNi5 hydrogen storage alloy powder with a particle size of 80-150 mesh to the binder solution obtained in step (2), and stir evenly to obtain mixed slurry; (4) Immerse the nickel foam prepared in step (1) into the mixed slurry prepared in step (3) and treat it for 20 minutes under the assistance of ultrasonic waves at a frequency of 40 kHz, so that the LaNi5 hydrogen storage alloy powder is uniformly filled and adhered to the pores of the nickel foam. (5) Place the nickel foam filled with LaNi5 powder hydrogen storage material in a sealed container, fill it with 0.5 MPa of argon gas for protection, heat it to 380°C at a heating rate of 5°C / min, and hold it at that temperature for 0.5 hours for curing. After curing, allow it to cool naturally to room temperature. (6) Performance test results: The material has a mass filling rate of 77.9%, an open porosity of 35.2%, an effective thermal conductivity of 5.2 W / (m·K), and a maximum hydrogen storage capacity of 0.92 wt.%. The time to absorb hydrogen to 90% saturation capacity is 8.7 minutes, and the capacity retention rate is 87.5% after 100 cycles.

[0054] Comparative Example 3

[0055] To verify the role of pore-forming agents in constructing gas diffusion channels, a control sample with insufficient pore-forming agent content was prepared: (1) Select nickel foam with a pore density of 30 PPI as a three-dimensional skeleton, clean it with anhydrous ethanol by ultrasonic cleaning and then dry it for later use. (2) Preparation of adhesive solution: Weigh 20 g of toluene solution containing silicone resin (mass fraction of 20%) (4 g of silicone resin and 16 g of toluene), add 10 g of polymethyl methacrylate to the above solution and mix evenly to obtain adhesive solution. The mass of pore-forming agent accounts for 33.3% of the total mass of adhesive solution; (3) Preparation of mixed slurry: Add 20 g of LaNi5 hydrogen storage alloy powder with a particle size of 80-150 mesh to the binder solution obtained in step (2), and stir evenly to obtain mixed slurry; (4) Immerse the nickel foam prepared in step (1) into the mixed slurry prepared in step (3) and treat it for 20 minutes under the assistance of ultrasonic waves at a frequency of 70 kHz, so that the LaNi5 hydrogen storage alloy powder is uniformly filled and adhered to the pores of the nickel foam. (5) Place the nickel foam filled with LaNi5 powder hydrogen storage material in a sealed container, fill it with 0.5 MPa of argon gas for protection, heat it to 380°C at a heating rate of 5°C / min, and hold it at that temperature for 0.5 hours to carry out the curing reaction. After curing, allow it to cool naturally to room temperature. (6) Performance test results: The morphology of the hydrogen storage material is as follows Figure 3As shown, due to insufficient pore-forming agent content (only 33.3%), a large number of unconnected films failed to form on the material surface, resulting in limited mass transfer performance. The material has a mass filling rate of 76.5%, an open porosity of 38.3%, an effective thermal conductivity of 9.2 W / (m·K), a maximum hydrogen storage capacity of 1.05 wt.%, a hydrogen absorption time to 90% saturation capacity of 7.0 minutes, and a capacity retention rate of 88.9% after 100 cycles.

[0056] Comparative Example 4

[0057] To verify the problem of insufficient bond strength caused by excessive pore-forming agent, a comparative sample with an excessively high pore-forming agent content was prepared: (1) Select nickel foam with a pore density of 30 PPI as a three-dimensional skeleton, clean it with anhydrous ethanol by ultrasonic cleaning and then dry it for later use. (2) Preparation of adhesive solution: Weigh 10 g of toluene solution containing silicone resin (mass fraction of 20%) (2 g of silicone resin and 8 g of toluene), add 50 g of sodium bicarbonate to the above solution and mix evenly to obtain adhesive solution. The mass of pore-forming agent accounts for 83.3% of the total mass of adhesive solution; (3) Preparation of mixed slurry: Add 28 g of LaNi5 hydrogen storage alloy powder with a particle size of 80-150 mesh to the binder solution obtained in step (2), and stir evenly to obtain mixed slurry; (4) Immerse the nickel foam prepared in step (1) into the mixed slurry prepared in step (3) and treat it for 20 minutes under the assistance of ultrasonic waves at a frequency of 60 kHz, so that the LaNi5 hydrogen storage alloy powder is uniformly filled and adhered to the pores of the nickel foam. (5) Place the nickel foam filled with LaNi5 powder hydrogen storage material in a sealed container, fill it with 0.5 MPa of argon gas for protection, heat it to 380°C at a heating rate of 5°C / min, and hold it at that temperature for 0.5 hours to carry out the curing reaction. After curing, allow it to cool naturally to room temperature. (6) Performance test results: The material has a mass filling rate of 61.2%, an open porosity of up to 88.3%, an effective thermal conductivity of 6.1 W / (m·K), and a maximum hydrogen storage capacity of 1.28 wt.%. The time to absorb hydrogen to 90% saturation capacity is 6.2 minutes, and the capacity retention rate drops to 79.9% after 100 cycles. There is obvious powder shedding during the cycling process.

[0058] Comparative Example 5

[0059] To verify the effect of curing process parameters on the hydrogen storage performance of powdered hydrogen storage materials, comparative samples with curing temperatures lower than the range of this invention were prepared: (1) Select nickel foam with a pore density of 30 PPI as a three-dimensional skeleton, clean it with anhydrous ethanol by ultrasonic cleaning and then dry it for later use. (2) Preparation of adhesive solution: Weigh 20 g of toluene solution containing silicone resin (mass fraction of 25%) (5 g of silicone resin and 15 g of toluene), add 50 g of sodium bicarbonate to the above solution and mix evenly to obtain adhesive solution. The mass of pore-forming agent accounts for 71.4% of the total mass of adhesive solution; (3) Preparation of mixed slurry: Add 28 g of LaNi5 hydrogen storage alloy powder with a particle size of 80-100 mesh to the binder solution obtained in step (2), and stir evenly to obtain mixed slurry; (4) Immerse the nickel foam prepared in step (1) into the mixed slurry prepared in step (3) and treat it for 20 minutes under the assistance of ultrasonic waves at a frequency of 60 kHz, so that the LaNi5 hydrogen storage alloy powder is uniformly filled and adhered to the pores of the nickel foam. (5) Place the nickel foam filled with LaNi5 hydrogen storage alloy powder in a sealed container, fill it with 0.5 MPa of argon gas for protection, heat it to 220°C at a heating rate of 5°C / min, and hold it at that temperature for 0.3 hours for curing. After curing, allow it to cool naturally to room temperature. (6) Performance test results: The material has a mass filling rate of 76.2% and an open porosity of 55.3%. Because the curing temperature (220℃) is lower than the preferred range of this invention (300~450℃), the high-temperature resistant resin failed to fully cure, resulting in insufficient mechanical strength of the adhesive layer. Simultaneously, although sodium bicarbonate partially decomposes at this temperature (the main decomposition temperature range is 50~270℃), due to incomplete resin curing, the CO2 gas generated by the decomposition cannot effectively construct stable pore channels in the semi-cured matrix, leading to a low open porosity. The effective thermal conductivity is 5.8 W / (m·K), and the maximum hydrogen storage capacity is 1.18 wt.%. The time to absorb hydrogen to 90% saturation capacity is 7.8 minutes, and the capacity retention rate decreases to 82.6% after 100 cycles.

[0060] The comparative test results of the material properties prepared in Examples 1-7 and Comparative Examples 1-5 are listed in Table 1: Table 1

[0061] Table 1 shows that the powdered hydrogen storage materials prepared in Examples 1-7 of this invention are significantly superior to the comparative examples in terms of heat transfer, mass transfer, effective hydrogen storage capacity, and cycle life. Specific analysis is as follows: (1) The effect of two-dimensional or three-dimensional framework on the thermal conductivity of powdered hydrogen storage materials Examples 1-7 used nickel foam, copper foam, stainless steel mesh, nickel mesh, or copper mesh as two-dimensional or three-dimensional skeletons, with effective thermal conductivity ranging from 7.2 to 18.6 W / (m·K). Comparative Example 1 used a traditional mechanical pressing process and added expanded graphite as a thermal conductive agent. Although the mass filling rate was as high as 94.5%, the interparticle contact thermal resistance was large, resulting in a thermal conductivity of only 6.8 W / (m·K). Comparative Example 2 used a nickel foam skeleton but did not add a pore-forming agent. After curing, a dense adhesive layer was formed, reducing the thermal conductivity to 5.2 W / (m·K). Comparative Example 4 had an excessively high pore-forming agent content (83.3%) and insufficient high-temperature resistant resin, failing to form a continuous heat conduction network, resulting in a thermal conductivity of only 6.1 W / (m·K). Comparative Example 5 had a low curing temperature (220℃), resulting in insufficient resin cross-linking and a thermal conductivity of only 5.8 W / (m·K).

[0062] (2) Effect of pore-forming agent on porosity and mass transfer rate

[0063] In Examples 1-7, the amount of pore-forming agent added was controlled within the range of 41.2% to 71.4%. During the curing process, it decomposed in situ to form gas diffusion channels, with an open porosity of 53.6% to 71.3%. The time to absorb hydrogen to 90% saturation capacity was 4.0 to 5.1 min, demonstrating excellent mass transfer performance. Comparative Example 2, without the addition of pore-forming agent, had an open porosity of only 35.2%. After curing, the high-temperature resistant resin formed a dense and continuous coating layer, hindering hydrogen diffusion and extending the hydrogen absorption time to 8.7 min. Comparative Example 3 had a pore-forming agent content of 33.3%, lower than the preferred range of this invention (40% to 80%), with an open porosity of only 38.3% and a hydrogen absorption time of 7.0 min, indicating that it is difficult to form effective gas diffusion channels when the proportion of pore-forming agent is below 40%. In Comparative Example 4, the pore-forming agent content was too high. Although the porosity reached 88.3%, the insufficient amount of high-temperature resistant resin resulted in insufficient bonding strength between the powder particles and the skeleton. During ultrasonic filling and curing, some powder particles agglomerated and became unevenly distributed, leading to localized blockage of mass transfer channels. The time to absorb hydrogen to 90% saturation capacity was 6.2 minutes. The hydrogen absorption kinetics curves of the powdered hydrogen storage materials prepared in Example 1 and Comparative Example 3 are shown below. Figure 4 As shown, under the same test conditions (25°C), the hydrogen absorption curve of Example 1 rises rapidly in the first 5 minutes, with a final hydrogen storage capacity of 1.48 wt.%, and it only takes 4.3 minutes to absorb hydrogen to 90% saturation capacity; while the curve of Comparative Example 3 rises more slowly, with a final hydrogen storage capacity of only 1.05 wt.%, and it takes 7.0 minutes to absorb hydrogen to 90% saturation capacity, which fully demonstrates the excellent mass transfer performance of the material of the present invention.

[0064] (3) Improvement of cycle stability by composite structure

[0065] Examples 1-7 exhibited excellent cycle stability, maintaining a capacity retention rate between 96.7% and 98.9% after 100 hydrogen adsorption / desorption cycles. This was attributed to the continuous thermal conduction network provided by the two-dimensional or three-dimensional framework, the effective fixation of the powdered hydrogen storage particles by the high-temperature resistant resin binder, and the in-situ construction of gas diffusion channels by the decomposition of the pore-forming agent. In contrast, Comparative Example 1 relied solely on physical particle contact, lacking adhesive support, resulting in a capacity retention rate of only 81.2% after 100 cycles. Comparative Examples 2 and 3, due to insufficient gas diffusion channels, had capacity retention rates of 87.5% and 88.9%, respectively. Comparative Examples 4 and 5, due to insufficient adhesive layer strength (due to insufficient high-temperature resistant resin and incomplete curing, respectively), saw capacity retention rates decrease to 79.9% and 82.6%, respectively, after 100 cycles. The results indicate that an appropriate amount of high-temperature resistant resin and sufficient curing are necessary conditions for ensuring cycle stability.

[0066] (4) The effect of two-dimensional or three-dimensional framework on the effective hydrogen storage capacity of powdered hydrogen storage materials

[0067] Except for Example 5, which uses magnesium-based powdered hydrogen storage material (MgH2) with a hydrogen storage capacity of up to 6.81 wt.%, the maximum hydrogen storage capacity of the other Examples 1-7 is 1.46~1.94 wt.%.

[0068] Although Comparative Example 1 had a high filler content, its open porosity was extremely low (<5.0%), meaning the internal hydrogen storage powder could not fully contact hydrogen and participate in the hydrogen absorption and desorption reactions, resulting in a maximum hydrogen storage capacity of only 1.12 wt.%. Comparative Example 2, without any pore-forming agent, had an open porosity of only 35.2%, with a large amount of hydrogen storage powder coated by a dense, high-temperature resistant resin, preventing sufficient contact with hydrogen, resulting in a maximum hydrogen storage capacity of only 0.92 wt.%, a 37.8% reduction compared to Example 1. Comparative Example 3 had a pore-forming agent content of 33.3%, below the preferred range of this invention, and an open porosity of 38.3%. Although this was an improvement over Comparative Example 2, the gas diffusion channels were still insufficient, resulting in a maximum hydrogen storage capacity of 1.05 wt.%, a 29.1% reduction compared to Example 1. Comparative Example 5, although having a suitable pore-forming agent content, suffered from insufficient curing temperature, leading to partial pore collapse and an open porosity of only 55.3%, resulting in a still low effective hydrogen storage capacity. These comparisons demonstrate that the present invention can significantly improve the utilization rate of powder and the effective hydrogen storage capacity by constructing a continuous gas diffusion channel with high porosity.

[0069] In summary, this invention selects hydrogen storage material particles with specific compositions and mesh sizes (45-200 mesh) as the initial hydrogen storage material, and uses a metal mesh with a specific mesh size (30-150 mesh) or a foam material with a specific pore density (30 PPI-120 PPI) as a two-dimensional or three-dimensional framework. It employs an organic solvent containing high-temperature resistant resin as a binder solution, precisely controlling the ratio of the pore-forming agent (sodium bicarbonate or polymethyl methacrylate) to the organic solvent containing high-temperature resistant resin. After the powder uniformly fills the framework under ultrasonic vibration assistance, it is heated and cured under argon protection. The resulting powdered hydrogen storage material exhibits a thermal conductivity more than 7 times higher than the initial powdered hydrogen storage material, and the time to absorb hydrogen to 90% saturation capacity is shortened by 22%-54% compared to traditional processes. Simultaneously, it significantly improves the effective hydrogen storage capacity, hydrogen absorption and desorption kinetics, and cycle stability. This invention achieves synergistic optimization of the thermal conductivity and mass transfer efficiency of powdered hydrogen storage materials, providing crucial support for the practical application and large-scale development of solid-state hydrogen storage technology.

[0070] The above description is merely a specific embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any variations or substitutions that can be easily conceived by those skilled in the art within the technical scope disclosed in the present invention should be included within the scope of protection of the present invention. Therefore, the scope of protection of the present invention should be determined by the scope of the claims.

Claims

1. A method for preparing a multidimensional powdered hydrogen storage material with high mass transfer and high heat transfer, characterized in that, Includes the following steps: S1. Select hydrogen storage material particles as the initial hydrogen storage material, select metal mesh or foam material as a two-dimensional or three-dimensional skeleton, and add pore-forming agent to an organic solvent containing high-temperature resistant resin to obtain a binder solution. S2. With the aid of binder solution and ultrasonic vibration, the hydrogen storage material particles are uniformly filled into the pores of the skeleton; S3. The filled material is heated and cured under an argon atmosphere to obtain the multidimensional powder hydrogen storage material with high mass transfer and high heat transfer.

2. The method for preparing a multidimensional powdered hydrogen storage material with high mass transfer and high heat transfer according to claim 1, characterized in that, In step S1, the hydrogen storage material particles are selected from one or more of magnesium-based, rare earth-based, zirconium-based, titanium-based metal hydrides and vanadium-based solid solution solid hydrogen storage materials, and their particle size ranges from 45 mesh to 200 mesh.

3. The method for preparing a multidimensional powdered hydrogen storage material with high mass transfer and high heat transfer according to claim 1, characterized in that, In step S1, the metal mesh is selected from stainless steel mesh, nickel mesh or copper mesh, and its mesh count ranges from 30 mesh to 150 mesh; the foam material is selected from nickel foam, copper foam or foam, and its pore density ranges from 30 PPI to 120 PPI.

4. The method for preparing a multidimensional powdered hydrogen storage material with high mass transfer and high heat transfer according to claim 1, characterized in that, In step S1, the organic solvent is selected from acetone, toluene, or xylene.

5. The method for preparing a multidimensional powdered hydrogen storage material with high mass transfer and high heat transfer according to claim 1, characterized in that, In step S1, the high-temperature resistant resin is selected from one of modified phenolic resin, epoxy phenolic composite resin or silicone resin, and the high-temperature resistant resin accounts for 20% to 25% of the total mass of the organic solvent and the high-temperature resistant resin.

6. The method for preparing a multidimensional powdered hydrogen storage material with high mass transfer and high heat transfer according to claim 1, characterized in that, In step S1, the pore-forming agent is selected from one or two of sodium bicarbonate and polymethyl methacrylate (PMMA), and the pore-forming agent accounts for 40% to 80% of the total mass of the high-temperature resistant resin organic solvent and the pore-forming agent.

7. The method for preparing a multidimensional powdered hydrogen storage material with high mass transfer and high heat transfer according to claim 1, characterized in that, In step S2, one of the following two methods is used to fill the skeleton with the hydrogen storage material particles: Method 1: Disperse the hydrogen storage material particles in the binder solution to obtain a mixed slurry, and then fill the skeleton with the mixed slurry; Method 2: First immerse the skeleton in the binder solution, and then fill the impregnated skeleton with the hydrogen storage material particles.

8. The method for preparing a multidimensional powdered hydrogen storage material with high mass transfer and high heat transfer according to claim 1, characterized in that, In step S2, the frequency of the ultrasonic vibration is 15 kHz to 100 kHz, and the ultrasonic treatment time is 10 minutes to 60 minutes.

9. The method for preparing a multidimensional powdered hydrogen storage material with high mass transfer and high heat transfer according to claim 1, characterized in that, In step S2, the hydrogen storage material particles are uniformly filled into the above-mentioned skeleton, and the mass filling rate is greater than 75%.

10. The method for preparing a multidimensional powdered hydrogen storage material with high mass transfer and high heat transfer according to claim 1, characterized in that, In step S3, the heating and curing is carried out under an argon atmosphere of 0.1 MPa to 1 MPa, the curing temperature is 300℃ to 450℃, the holding time is 0.5 h to 1 h, and the heating rate is 3℃ / min to 6℃ / min.

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