A2B7-type y-mg-ni hydrogen storage material and method for preparing the same

Abstract

The application provides an A2B7 type Y-Mg-Ni hydrogen storage material and a preparation method thereof, and belongs to the technical field of hydrogen storage materials. 1‑a‑b Mg a C b Ni c D d , wherein 0.05<=a<=0.25, 0<=b<=0.2, 3.25<=c<=3.45, 0<=d<=0.2, C is at least one selected from Ce, Pr, Nd, Sm, Gd, and D is at least one selected from Mn, Mo, Fe, Ti, Si and W. The hydrogen storage alloy material is doped with elements and modified in process, so that the pure A2B7 type hydrogen storage material is obtained, the hydrogen storage capacity of the rare earth hydrogen storage alloy, the hydrogen absorption and release cycle stability and the hydrogen absorption and release plateau pressure can be improved simultaneously.

Description

Technical Field

[0001] The present invention relates to the technical field of hydrogen storage materials, and more particularly to an A2B7 type Y-Mg-Ni series hydrogen storage material and a preparation method thereof. Background Art

[0002] Hydrogen energy holds a significant position in the new energy sector due to its exceptional environmental credentials and high energy density. As a clean energy source, hydrogen produces only water upon combustion and emits no harmful gases, including greenhouse gases and other pollutants, making its environmental impact virtually negligible. Furthermore, hydrogen boasts an extremely high energy density, three times that of gasoline. This means that for the same mass, hydrogen releases far more energy than traditional fossil fuels, giving it significant advantages in applications requiring high energy output, such as heavy-duty transportation and industrial processes. These characteristics make hydrogen energy a crucial energy source for achieving energy transition and addressing climate change. However, within the entire hydrogen energy industry chain, the storage and transportation of hydrogen remain bottlenecks restricting its development.

[0003] Solid-state hydrogen storage materials, as a highly safe and high-volume hydrogen storage method, are widely considered a key approach to breaking through bottlenecks in the future development of the hydrogen energy industry. Among the numerous hydrogen storage materials, rare earth hydrogen storage materials have attracted considerable attention due to their ease of activation and excellent kinetic properties. Although traditional AB5-type rare earth hydrogen storage materials have achieved large-scale application, their low theoretical hydrogen storage capacity (1.4 wt%) is no longer sufficient to meet the growing demand for these materials. Research on La-Mg / Y-Ni-based rare earth hydrogen storage materials has primarily focused on electrochemical applications, specifically as negative electrode materials for nickel-hydrogen batteries, and has rarely been used in solid-state hydrogen storage devices. Furthermore, the relative atomic mass of La (138.9) is significantly greater than that of Y (88.9) and Mg (24.3). This results in a lower hydrogen storage capacity for La-Mg / Y-Ni-based hydrogen storage alloys, which offer less significant advantages than AB5-type alloys and exhibit lower reversible cycling capacity.

[0004] Therefore, there is an urgent need for a rare earth hydrogen storage material with high hydrogen storage capacity, high hydrogen storage cycle stability and high hydrogen absorption and desorption platform pressure to promote its further application in solid-state hydrogen storage devices. Summary of the Invention

[0005] The purpose of the present invention is to address the defects of existing rare earth hydrogen storage alloys, such as the need to improve the hydrogen storage capacity and cycle stability, as well as the inability to have a high hydrogen absorption and desorption platform pressure. By doping the hydrogen storage alloy materials with elements and performing process modifications, the hydrogen storage capacity, cycle stability and platform pressure of the rare earth hydrogen storage alloys can be improved at the same time.

[0006] To achieve the above object, the present invention adopts the following technical solutions:

[0007] In a first aspect of the present application, there is provided an A2B7-type Y-Mg-Ni hydrogen storage material, having a general structure Y 1-a-b Mg a C b Ni c D d wherein 0.05≤a≤0.25, 0≤b≤0.2, 3.25≤c≤3.45, 0≤d≤0.2, C is selected from at least one of Ce, Pr, Nd, Sm, Gd, and D is selected from at least one of Mn, Mo, Fe, Ti, Si, and W.

[0008] As an embodiment of the present application, the hydrogen storage material includes a (Y, Mg)2Ni7-2H-type phase and a (Y, Mg)2Ni7-3R-type phase.

[0009] As an embodiment of the present application, the (Y, Mg)2Ni7-2H-type phase and the (Y, Mg)2Ni7-3R-type phase are present in a ratio of 1: (1-5).

[0010] As an embodiment of the present application, the general structure Y 1-a-b Mg a C b Ni c D d wherein 0.08≤a≤0.15.

[0011] As an embodiment of the present application, the general structure Y 1-a-b Mg a C b Ni c D d wherein 0≤b≤0.1.

[0012] As an embodiment of the present application, the general structure Y 1-a-b Mg a C b Ni c D d wherein 3.40≤c≤3.45.

[0013] As an embodiment of the present application, the general structure Y 1-a-b Mg a C b Ni c D d wherein 0.05≤d≤0.1.

[0014] As an embodiment of the present application, the general structure Y 1-a-b Mg a C b Ni c D dIn particular, 0 < b / a ≤ 0.5.

[0015] As an embodiment of the present application, the structural general formula Y 1-a-b Mg a C b Ni c D d In particular, C is Ce or Pr, and D is at least one selected from Mo, Ti, and W.

[0016] As an embodiment of the present application, the hydrogen storage material has a hydrogen storage capacity of ≥1.75wt% at 25℃ under a pressure of 5MPa, an effective hydrogen release amount of ≥1.63wt% at a hydrogen release pressure of 0.1MPa or above, and a capacity retention rate of ≥95% after 200 cycles of hydrogen absorption and release.

[0017] In a second aspect of the present application, a preparation method of the A2B7-type Y-Mg-Ni hydrogen storage material of the first aspect of the present application is provided, which comprises the following steps: after ingredients are prepared according to a metering ratio, a cast alloy is obtained by smelting, and the A2B7-type Y-Mg-Ni hydrogen storage material is obtained after annealing.

[0018] As an embodiment of the present application, the raw materials for the ingredients include metal raw materials or alloy raw materials.

[0019] As an embodiment of the present application, the annealing process is as follows: first, the temperature is raised to 600℃ at a temperature raising rate of 5-10℃ / min; then, the temperature is raised to 750-850℃ at a temperature raising rate of 1-3℃ / min, and the temperature is kept for 0.5-1.5h; then, the temperature is raised to 925-1050℃ at a temperature raising rate of 1-3℃ / min, and the temperature is kept for 6-36h; finally, the temperature is cooled.

[0020] Compared with the prior art, the present application has the following beneficial effects:

[0021] The present application improves the hydrogen storage capacity, the hydrogen absorption and release cycle stability, and the hydrogen absorption and release plateau pressure of the rare earth hydrogen storage alloy by element doping and process modification. BRIEF DESCRIPTION OF DRAWINGS

[0022] Figure 1 The XRD spectrum of the A2B7-type Y-Mg-Ni hydrogen storage material prepared for Example 1 of the present application. DETAILED DESCRIPTION

[0023] For the purpose of better illustrating the object, technical scheme and advantages of the present application, the present application will be further described in combination with specific examples, but the examples do not limit the present application in any form. Unless otherwise specified, the reagents, methods and devices used in the present application are conventional reagents, methods and devices in the technical field. Unless otherwise specified, the reagents and materials used in the present application are commercially available.

[0024] In the present invention, the technical features described in an open manner include closed technical solutions composed of the listed features, and also include open technical solutions containing the listed features.

[0025] In the present invention, when referring to numerical ranges, unless otherwise specified, the numerical ranges are considered continuous and include the minimum and maximum values ​​of the range, as well as every value between such minimum and maximum values. Furthermore, when a range refers to an integer, every integer between the minimum and maximum values ​​of the range is included. In addition, when multiple ranges are provided to describe a feature or characteristic, the ranges can be combined. In other words, unless otherwise specified, all ranges disclosed herein should be understood to include any and all subranges subsumed therein.

[0026] The reagents and instruments used in the present invention without indicating the manufacturer are all conventional products that can be purchased from the market.

[0027] In the first aspect of the present invention, an embodiment of the present invention provides an A2B7 type Y-Mg-Ni series hydrogen storage material, the general structural formula of the hydrogen storage material is: 1-a-b Mg a C b Ni c D d , wherein, 0.05≤a≤0.25, 0≤b≤0.2, 3.25≤c≤3.45, 0≤d≤0.2, C is selected from at least one of Ce, Pr, Nd, Sm, and Gd, and D is selected from at least one of Mn, Mo, Fe, Ti, Si, and W.

[0028] The present invention utilizes the smaller atomic radii of Y and Mg to reduce the unit cell volume of the Y-Mg-Ni hydrogen storage material alloy, thereby increasing the hydrogen absorption and desorption platform pressure of the hydrogen storage material. Furthermore, due to the relatively small relative atomic masses of Y and Mg, a Y-Mg-Ni-based alloy with Y and Mg as the base material exhibits a higher hydrogen storage capacity at the same ratio. Furthermore, further doping of the A-side (Y-Mg phase) with other rare earth elements and the B-side (Ni phase) with specific metal elements can improve the alloy phase structure of the hydrogen storage material, forming (Y,Mg)2Ni7-2H and (Y,Mg)2Ni7-3R phases within the hydrogen storage material, significantly enhancing the hydrogen absorption capacity and cyclic stability of the hydrogen storage material.

[0029] In some embodiments of the present invention, the hydrogen storage material includes a (Y,Mg)2Ni7-2H type phase and a (Y,Mg)2Ni7-3R type phase.

[0030] Among them, in the rare earth superlattice structure phase, the structural stability of each phase is (Y,Mg)6Ni 24 >(Y,Mg)5Ni19 >(Y,Mg)2Ni7>(Y,Mg)Ni3decreases in order, but the theoretical hydrogen storage capacity presents the opposite trend, i.e., (Y,Mg)6Ni 24 <(Y,Mg)5Ni 19 <(Y,Mg)2Ni7<(Y,Mg)Ni3. This characteristic makes the (Y,Mg)2Ni7 phase achieve the best balance between structural stability and hydrogen storage capacity, and exhibits excellent comprehensive hydrogen storage performance. In addition, the superlattice structure is formed by the [A2B4] and [AB5] substructures alternately stacking along the c-axis, wherein the [A2B4] substructure exists in two crystal configurations of C14 and C15, and this polymorphism leads to the synchronous generation of the 2H-type (Y,Mg)2Ni7 phase with the P63 / mmc space group and the 3R-type (Y,Mg)2Ni7 phase with the R-3m space group during the phase formation process. The existence of the (Y,Mg)2Ni7-2H phase structure and the (Y,Mg)2Ni7-3R phase structure can significantly improve the hydrogen storage capacity of the hydrogen storage material; the existence of the (Y,Mg)2Ni7-3R phase structure can reduce the hydrogen absorption and desorption platform pressure, but during the hydrogen absorption and desorption cycle of the R-3m phase, it is easy to transform into a low-symmetry phase (such as a monoclinic phase), resulting in capacity attenuation.

[0031] Therefore, by systematically regulating the type, ratio and content of the doping elements, the relative content of the two phases can be effectively adjusted and the cell structure parameters can be optimized, thereby synergistically improving the effective capacity and cycle stability of the hydrogen storage system while maintaining suitable reversible hydrogen absorption and desorption platform pressure.

[0032] In some embodiments of the present application, the ratio of the (Y,Mg)2Ni7-2H phase and the (Y,Mg)2Ni7-3R phase is 1: (1-5).

[0033] In some embodiments of the present application, the structural general formula Y 1-a-b Mg a C b Ni c D d 0.08≤a≤0.15.

[0034] In some embodiments of the present application, the structural general formula Y 1-a-b Mg a C b Ni c D d 0≤b≤0.1.

[0035] In some embodiments of the present application, the structural general formula Y 1-a-b Mg a C b Ni c D d 3.40≤c≤3.45.

[0036] In some embodiments of the present invention, the structural formula Y 1-a-b Mg a C b Ni c D d In the medium, 0.05≤d≤0.1.

[0037] In some embodiments of the present invention, the structural formula Y 1-a-b Mg a C b Ni c D d Medium, 0

[0038] In some embodiments of the present invention, the structural formula Y 1-a-b Mg a C b Ni c D d In the embodiment, C is Ce or Pr, and D is selected from at least one of Mn, Ti, and W. The combination of appropriate doping elements can further improve the effective hydrogen release capacity of the hydrogen storage alloy material.

[0039] The A2B7 type Y-Mg-Ni series hydrogen storage material of the present invention has a hydrogen storage capacity of ≥1.75wt% at 25°C and a pressure of 5MPa; an effective hydrogen release amount of ≥1.63wt% at a hydrogen release pressure of above 0.1MPa; and a capacity retention rate of ≥95% after 200 cycles of hydrogen absorption and desorption.

[0040] In a second aspect of the present invention, an embodiment of the present invention further provides a method for preparing the A2B7 type Y-Mg-Ni series hydrogen storage material according to the first aspect of the present invention, comprising the following steps:

[0041] After the ingredients are mixed according to the stoichiometric ratio, the cast alloy is obtained by smelting, and the A2B7 type Y-Mg-Ni series hydrogen storage material is obtained after annealing.

[0042] In the present invention, there is no limitation on the raw materials used for the ingredients. High-purity metal raw materials or alloy raw materials can be used. As long as the general structural formula Y 1-a-b Mg a C b Ni c D d of hydrogen storage materials. ​

[0043] In the present invention, the smelting process is not limited, as long as the elements in the hydrogen storage material alloy can be evenly distributed.

[0044] In some embodiments of the present invention, the annealing process is: first, heating to 600°C at a heating rate of 5~10°C / min; then heating to 750°C~850°C at a heating rate of 1~3°C / min, and keeping warm for 0.5~1.5h; then heating to 925°C~1050°C at a heating rate of 1~3°C / min, and keeping warm for 6h~36h; and finally cooling.

[0045] A relatively rapid heating rate is used in the initial stage to suppress Mg volatilization, while a holding treatment is used to achieve a dynamic equilibrium of magnesium within the system. Subsequent heating steps require strict control of the heating rate: appropriately slowing the heating rate promotes the complete dissociation of the A2B7 phase in the as-cast alloy, while ensuring complete transformation of the AB5 phase into the target A2B7 phase through peritectic reactions and achieving sufficient grain growth. Excessively high heating rates will lead to insufficient reaction kinetics and reduce nucleation density, while too low a rate may induce secondary crystallization, forming impurity phases such as A5B19. Temperature control must be maintained between 925°C and 1050°C. Below the critical lower limit, the original impurity phase cannot be completely eliminated through peritectic reactions. Exceeding the upper limit may cause the A2B7 phase to reversely transform into the A5B19 phase or decompose into the AB5 phase.

[0046] After multiple stages of heat preservation, some non-equilibrium defects are repaired by annealing through atomic diffusion, while a moderate amount of "functional defects" (such as low-density dislocations and nanoscale vacancy clusters) is retained to improve the stability of the hydride and enhance the stability of the hydrogen absorption and desorption cycles. Therefore, through this progressive temperature control, the balance between hydrogen storage capacity and hydrogen absorption and desorption cycle stability can be optimized.

[0047] The following are specific embodiments of the present invention.

[0048] Example 1

[0049] This embodiment provides an A2B7 type Y-Mg-Ni series hydrogen storage material with the general structural formula Y 0.75 Mg 0.13 Ce 0.12 Ni 3.33 Mn 0.12 , the preparation method comprises the following steps:

[0050] S1: According to the chemical structure formula Y 0.75 Mg 0.13 Ce 0.12 Ni 3.33 Mn 0.12, weighing Y, Mg, Ce, Ni, and Mn metal elements (all with a purity of more than 99.9%). It should be noted that, considering the volatilization of Mg, the actual amount of Mg added needs to be 50wt% more than the theoretical amount; the mixed raw materials obtained by evenly mixing the weighed metal element raw materials are placed in a quartz crucible in an induction melting furnace, and after evacuating to a vacuum degree of less than 0.005Pa, induction melting is carried out under the protection of an argon atmosphere of 0.5bar; the molten alloy is poured into a copper mold and cooled to obtain a cast alloy;

[0051] S2: The cast alloy prepared in step S1 was polished to a bright finish using an electric grinder to remove the oxide layer on the surface of the alloy ingot. The alloy ingot was then wrapped with tantalum foil and placed in a quartz tube, which was evacuated to 1×10 -3 Pa, introduce argon to 0.5 bar and seal, then place in a muffle furnace and anneal according to the following process:

[0052] ① Heating from room temperature to 600°C at a heating rate of 5°C / min → ② then heating to 800°C at a heating rate of 1°C / min, holding for 1 hour → ③ then heating to 950°C at a heating rate of 1°C / min, holding for 12 hours → ④ then naturally cooling to room temperature (below 30°C) and removing to obtain the A2B7-type Y-Mg-Ni-based hydrogen storage material;

[0053] The prepared hydrogen storage material was tested by X-ray powder diffractometer (XRD) to analyze the phase structure composition of the hydrogen storage material alloy. The XRD test results were fitted using the Rietveld method. The fitting results are shown in Figure 1 From the figure, we can get the results of phase content, unit cell parameters, etc., see Table 1 for details.

[0054] Examples 2 to 14, Comparative Examples 1 to 4

[0055] A series of A2B7 type Y-Mg-Ni series hydrogen storage materials are provided, which are prepared according to the method of Example 1. The difference from Example 1 is that:

[0056] The types and amounts of elements in the general structural formula are slightly different; and during the annealing process, the heating rate and the holding temperatures in different holding sections are slightly different;

[0057] However, the annealing process needs to meet the following requirements: first, heat the temperature to 600℃ at a heating rate of 5~10℃ / min; then heat the temperature to 750℃~850℃ at a heating rate of 1~3℃ / min, and keep it at that temperature for 0.5~1.5h; then heat the temperature to 925℃~1050℃ at a heating rate of 1~3℃ / min, and keep it at that temperature for 6h~36h; finally, cool it down;

[0058] The prepared different A2B7 type Y-Mg-Ni hydrogen storage materials were also characterized by XRD, and the phase composition and cell parameters of the hydrogen storage materials are shown in Table 1.

[0059] Table 1 Hydrogen storage materials

[0060]

[0061] Example 15 provides an A2B7 type Y-Mg-Ni hydrogen storage material, with a general formula of Y 0.75 Mg 0.13 Ce 0.12 Ni 3.33 Mn 0.12 , which is prepared by referring to the method of Example 1, except that the annealing process in step S2 is as follows:

[0062] ① then heated to 800℃ at a heating rate of 1℃ / min, and kept for 1h→ ② then heated to 950℃ at a heating rate of 1℃ / min, and kept for 12h→ ③ then naturally cooled to room temperature (lower than 30℃) and taken out, to obtain the A2B7 type Y-Mg-Ni hydrogen storage material.

[0063] Example 16 provides an A2B7 type Y-Mg-Ni hydrogen storage material, with a general formula of Y 0.75 Mg 0.13 Ce 0.12 Ni 3.33 Mn 0.12 , which is prepared by referring to the method of Example 1, except that the annealing process in step S2 is as follows:

[0064] ① heated from room temperature to 600℃ at a heating rate of 5℃ / min→ ② then heated to 950℃ at a heating rate of 1℃ / min, and kept for 13h→ ③ then naturally cooled to room temperature (lower than 30℃) and taken out, to obtain the A2B7 type Y-Mg-Ni hydrogen storage material.

[0065] Performance test

[0066] The hydrogen storage performance of the A2B7 type Y-Mg-Ni hydrogen storage materials prepared in the above examples and comparative examples was tested, and the specific test items and test methods are as follows:

[0067] (1) The Sieverts method was used to activate hydrogen absorption at 25℃ and 5MPa, and then test the PCT performance of the alloy, and draw the PCT curve; the hydrogen storage material was activated first, and the activation conditions were as follows: 5MPa H2 was filled at room temperature (25℃), and the pressure-time change curve was recorded and the saturated hydrogen absorption amount was calculated, and then the hydrogen was removed at 300℃ for 1h. After activation, the PCT curve was tested and drawn at room temperature.

[0068] The PCT curve can be used to obtain properties such as the hydrogen desorption platform pressure at 25°C and the effective hydrogen desorption amount (the hydrogen desorption amount above the hydrogen desorption pressure of 0.1 MPa is recorded as the effective hydrogen desorption amount). The results are shown in Table 2.

[0069] (2) Hydrogen absorption and desorption cycle performance test:

[0070] At room temperature (25°C), 5 MPa high-purity (purity>99.99%) hydrogen was introduced into the container containing the activated sample to be tested. After the hydrogen absorption reached saturation, the reactor was quickly heated to 300°C to release hydrogen for 50 minutes, and then air-cooled to room temperature (25°C) to absorb hydrogen for 30 minutes. This cycle was repeated 200 times, and the hydrogen absorption content was recorded. The results are shown in Table 2. In Table 2, capacity retention (%) = η 200 / η0*100%, where η 200 It represents the hydrogen absorption content of the sample to be tested during the 200th cycle of hydrogen absorption and desorption, and η0 represents the initial hydrogen absorption content of the sample to be tested under the hydrogen absorption and desorption conditions.

[0071] Table 2

[0072]

[0073] The above results of the above embodiments and comparative examples show that:

[0074] By comparing Example 14 with Comparative Example 1, when the B / A value of the alloy design is less than 3.2, the same preparation method and heat treatment process are used to obtain an alloy having a phase structure of (Y, Mg) Ni3 phase. Although it has a high hydrogen storage capacity, the hydrogen release platform pressure and effective hydrogen storage capacity are low, and the cycle retention rate is only 89.1%. The reason is that the structural stability of the (Y, Mg) Ni3 phase is not as good as that of the (Y, Mg) 2Ni7 phase, and it is easy to hydrogen-induced amorphization during the cycle, resulting in a decrease in capacity.

[0075] In Comparative Examples 2-4, there is no pure (Y,Mg)2Ni7 phase, which results in a decrease in the hydrogen storage capacity of the alloy and further reduces the effective hydrogen desorption capacity.

[0076] The results of the above embodiments and comparative examples indicate that the general design and preparation method of the present invention can produce a Y-Mg-Ni series hydrogen storage alloy containing only an A2B7 structure. This type of hydrogen storage alloy has a hydrogen desorption plateau pressure exceeding 0.25 MPa, an effective hydrogen desorption capacity exceeding 1.63 wt%, and excellent cyclic stability, making it more suitable for use in solid-state hydrogen storage devices.

[0077] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and are not intended to limit the scope of protection of the present invention. Although the present invention has been described in detail with reference to preferred embodiments, those skilled in the art should understand that the technical solutions of the present invention may be modified or replaced by equivalents without departing from the essence and scope of the technical solutions of the present invention.

Claims

1. An A2B7 type Y-Mg-Ni series hydrogen storage material, characterized in that: The general structural formula of hydrogen storage material is: 1-a- b Mg a C b Ni c D d , wherein, 0.08≤a≤0.13, 0≤b≤0.2, 3.25≤c≤3.45, 0≤d≤0.2, C is selected from at least one of Ce, Pr, Nd, Sm, and Gd, and D is selected from at least one of Mn, Mo, Fe, Ti, Si, and W; the general structural formula is Y 1-a-b Mg a C b Ni c D d Medium, 0 <b / a≤0.5; The hydrogen storage material includes a (Y,Mg)2Ni7-2H type phase and a (Y,Mg)2Ni7-3R type phase; the ratio of the (Y,Mg)2Ni7-2H type phase to the (Y,Mg)2Ni7-3R type phase is 1:(1-5); The preparation method of the A2B7 type Y-Mg-Ni series hydrogen storage material comprises the following steps: After the ingredients are mixed according to the stoichiometric ratio, the cast alloy is smelted and annealed to obtain the A2B7 type Y-Mg-Ni series hydrogen storage material. The annealing process is as follows: first, the temperature is raised to 600°C at a heating rate of 5-10°C / min; then, the temperature is raised to 750°C-850°C at a heating rate of 1-3°C / min, and the temperature is kept at this temperature for 0.5-1.5 hours; then, the temperature is raised to 925°C-1050°C at a heating rate of 1-3°C / min, and the temperature is kept at this temperature for 6-36 hours; and finally, the material is cooled.

2. The A2B7 type Y-Mg-Ni hydrogen storage material according to claim 1, characterized in that: Structural formula Y 1-a- b Mg a C b Ni c D d At least one of the following characteristics is met: （1）0≤b≤0.1； （2）3.4≤c≤3.45； （3）0.05≤d≤0.1。 3. The A2B7 type Y-Mg-Ni hydrogen storage material according to claim 1, characterized in that The general structural formula Y 1-a- b Mg a C b Ni c D d In the embodiment, C is Ce or Pr, and D is selected from at least one of Mn, Ti, and W.

4. The A2B7 type Y-Mg-Ni hydrogen storage material according to claim 1, characterized in that The hydrogen storage capacity of the hydrogen storage material at 25°C and 5MPa pressure is ≥1.75wt%; the effective hydrogen release capacity above a dehydrogenation pressure of 0.1MPa is ≥1.63wt%; After 200 cycles of hydrogen absorption and desorption, the capacity retention rate is ≥95%.

5. The A2B7 type Y-Mg-Ni hydrogen storage material according to claim 1, characterized in that The raw materials of the batch include metal raw materials or alloy raw materials.

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