High-platform-pressure vanadium-based hydrogen storage alloy, preparation method and application thereof

Abstract

The application belongs to the technical field of hydrogen storage alloy materials, and relates to a high-platform-pressure vanadium-based hydrogen storage alloy as well as a preparation method and application thereof. The high-platform-pressure vanadium-based hydrogen storage alloy is obtained by weighing elemental metals according to atomic proportions, mixing and batching, smelting, mechanical crushing and screening. a Cr b V c Mo x RE y , wherein RE is at least one of La, Ce or Y, 0.015<=a<=0.075, 0.075<=b<=0.255, 0.7<=c<=0.9, and a+b+c=1; 0.01<=x<=0.05, 0.01<=y<=0.05. The high-platform-pressure vanadium-based hydrogen storage alloy provided by the application has excellent performance, fast hydrogen absorption and release rate, excellent activation performance, and the maximum hydrogen absorption amount of the optimal sample is greater than or equal to 2.3wt% when the activation temperature is less than or equal to 25 DEG C, the maximum hydrogen release amount is greater than or equal to 2.2wt%, the platform pressure is greater than or equal to 2MPa, and the hydrogen release time is 3min.

Description

TECHNICAL FIELD

[0001] The application belongs to the technical field of hydrogen storage alloy materials, and relates to a high plateau pressure vanadium-based hydrogen storage alloy and a preparation method and application thereof. BACKGROUND

[0002] Hydrogen energy is the ideal energy in the 21st century. As a renewable secondary energy, hydrogen energy has a rich source. Compared with other chemical fuels, hydrogen has a high mass energy density, and the released energy is as high as 142 MJ / kg, which is 3.25 times that of gasoline and 3.4 times that of natural gas. The hydrogen energy industry chain as a whole can be divided into three major links of hydrogen energy production, hydrogen energy storage and transportation, and hydrogen energy application. Hydrogen storage and transportation is a key bridge connecting the hydrogen production end and the demand end. Solid-state hydrogen storage is expected to become one of the mainstream ways of hydrogen energy storage in the future due to its high hydrogen storage density, low hydrogen storage pressure, good safety, and high hydrogen release purity.

[0003] At present, hydrogen storage alloys are mainly divided into five categories, namely magnesium system, vanadium system, zirconium system, titanium-iron system and rare earth system. Among them, vanadium-based alloys have become one of the most promising high-capacity metal hydrogen storage materials due to their high hydrogen storage capacity and the advantages of hydrogen absorption and release at normal temperature and pressure. Although vanadium-based alloys have high hydrogen storage capacity, the problems of difficult activation and poor hydrogen absorption and release kinetics still hinder their development.

[0004] At present, some technical solutions for reducing the activation temperature of hydrogen storage alloy or improving the kinetic performance have been disclosed in the prior art. For example, CN114293086A discloses a hydrogen storage high-entropy alloy and a preparation method thereof. The chemical general formula of the hydrogen storage alloy is Ti a Zr b Fe c Mn d Cr e V f , wherein 5at%≤a≤35at%, 5at%≤b≤35at%, 5at%≤c≤35at%, 5at%≤d≤35t%, 5t%≤e≤35at%, 5at%≤f≤35at%, and a+b+c+d+e+f=100. The hydrogen storage alloy is activated by hydrogen absorption-hydrogen release cycle once at a temperature of 350-400℃ and a pressure of 7MPa. The maximum hydrogen absorption capacity (>1.8wt%) can be reached in a few hundred seconds, but the hydrogen release time is relatively long, and it takes about 600s to reach the maximum hydrogen release capacity (30℃, 1.1wt%). Moreover, the plateau pressure is very low, which is not conducive to the release of hydrogen. CN114381644A discloses a vanadium-titanium-based hydrogen storage alloy powder and an efficient preparation method thereof. The chemical general formula of the hydrogen storage alloy is V a Ti b Cr c Fe d Mn e Cef Wherein, 0.2≤a≤0.7, 0.15≤b≤0.40, 0.17≤c≤0.43, 0.05≤d≤0.1, 0.01≤e≤0.1, 0.01≤f≤0.2, the hydrogen storage alloy does not need high-temperature activation, but the hydrogen absorption and desorption time is longer, and the platform pressure is lower, which is not conducive to the release of hydrogen.

[0005] Therefore, it is urgent to develop a vanadium-based hydrogen storage alloy with high platform pressure, and a preparation method and application thereof. The prepared vanadium-based hydrogen storage alloy not only has high hydrogen storage capacity, fast hydrogen absorption and desorption time, high hydrogen storage and desorption platform pressure and cycle stability, but also has the characteristics of simple, fast and effective preparation method. SUMMARY

[0006] In view of the technical problems in the prior art that low activation temperature, high hydrogen storage capacity, fast hydrogen absorption and desorption time, high hydrogen storage and desorption platform pressure and cycle stability cannot be considered, the present application provides a vanadium-based hydrogen storage alloy with high platform pressure, and a preparation method and application thereof. The preparation method provided by the present application significantly improves the platform pressure, activation performance, hydrogen absorption and desorption rate, effective hydrogen desorption capacity and cycle stability of the alloy through the optimization design and vacuum melting of each component. The preparation method has a simple process flow, low cost, is conducive to large-scale production, and has good industrial application prospect.

[0007] In order to achieve the above-mentioned purposes, the technical scheme of the present application is as follows:

[0008] A vanadium-based hydrogen storage alloy with high platform pressure, which comprises Ti a Cr b V c Mo x RE y Wherein, RE is at least one of La, Ce or Y, 0.015≤a≤0.075, 0.075≤b≤0.255, 0.7≤c≤0.9, and a+b+c=1; 0.01≤x≤0.05, 0.01≤y≤0.05.

[0009] Further, based on the Ti-Cr-V hydrogen storage alloy, by adding RE element and metal molybdenum and controlling the content thereof, the prepared vanadium-based hydrogen storage alloy can be directly activated at low temperature without the need for high-temperature or high-pressure activation process, and the hydrogen absorption and desorption kinetics is accelerated on the basis of ensuring high hydrogen absorption and desorption capacity. Compared with the prior art which is activated at high temperature and is not conducive to the use of the material in actual situation, the low activation temperature and high platform pressure of the present application can make the material absorb and desorb hydrogen at room temperature and quickly desorb hydrogen.

[0010] Further, the present application specifies 0.015≤a≤0.075, for example 0.015, 0.02, 0.025, 0.03, 0.035, 0.04, 0.045, 0.05, 0.055, 0.06, 0.065, 0.07 or 0.075, etc., but not limited to the listed values, other values not listed within the range are also applicable.

[0011] Further, the present application specifies 0.075≤b≤0.255, for example 0.075, 0.085, 0.095, 0.105, 0.115, 0.125, 0.135, 0.145, 0.155, 0.165, 0.175, 0.185, 0.195, 0.205, 0.215, 0.225, 0.235, 0.245 or 0.255, etc., but not limited to the listed values, other values not listed within the range are also applicable.

[0012] Further, the present application specifies 0.7≤c≤0.9, for example 0.7, 0.8 or 0.9, etc., but not limited to the listed values, other values not listed within the range are also applicable.

[0013] Further, the present application specifies 0.01≤x≤0.05, for example 0.01, 0.02, 0.03, 0.04 or 0.05, etc., but not limited to the listed values, other values not listed within the range are also applicable.

[0014] Further, the present application specifies 0.01≤y≤0.05, for example 0.01, 0.02, 0.03, 0.04 or 0.05, etc., but not limited to the listed values, other values not listed within the range are also applicable.

[0015] Further, the high plateau pressure vanadium-based hydrogen storage alloy is Ti a Cr b V c Mo x RE y , wherein the atomic ratio of a and b is (1-3):(3-17), 0.8≤c≤0.9, and a+b+c=1; 0.01≤x≤0.05, 0.01≤y≤0.05.

[0016] Preferably, the high plateau pressure vanadium-based hydrogen storage alloy is Ti a Cr b V c Mo x RE ywherein RE is at least one of La, Ce or Y, 0.015≤a≤0.05, 0.075≤b≤0.17, 0.8≤c≤0.9, and a+b+c=1; 0.01≤x≤0.03, 0.01≤y≤0.03.

[0017] Further, the present application describes 0.015≤a≤0.05, for example, 0.015, 0.0175, 0.02, 0.0225, 0.025, 0.0275, 0.03, 0.0325, 0.035, 0.0375, 0.04, 0.0425, 0.045, 0.0475 or 0.05, etc., but not limited to the listed values, other values not listed in the range of values are also applicable.

[0018] Further, the present application describes 0.075≤b≤0.17, for example, 0.075, 0.08, 0.085, 0.09, 0.095, 0.1, 0.105, 0.11, 0.115, 0.12, 0.125, 0.13, 0.135, 0.14, 0.145, 0.15, 0.155, 0.16, 0.165 or 0.17, etc., but not limited to the listed values, other values not listed in the range of values are also applicable.

[0019] Further, the present application describes 0.8≤c≤0.9, for example, 0.8, 0.85 or 0.9, etc., but not limited to the listed values, other values not listed in the range of values are also applicable.

[0020] Further, the present application describes 0.01≤x≤0.03, for example, 0.01, 0.015, 0.02, 0.025 or 0.3, etc., but not limited to the listed values, other values not listed in the range of values are also applicable.

[0021] Further, the present application describes 0.01≤y≤0.03, for example, 0.01, 0.015, 0.02, 0.025 or 0.3, etc., but not limited to the listed values, other values not listed in the range of values are also applicable.

[0022] Further, the activation temperature of the high plateau pressure vanadium-based hydrogen storage alloy is ≤25℃, and the plateau pressure is ≥2MPa.

[0023] Further, the preparation method of the high plateau pressure vanadium-based hydrogen storage alloy comprises the following steps:

[0024] (1) batching: elemental metals are weighed according to atomic proportions and are batched to obtain a mixture;

[0025] (2) melting: the mixture of step (1) is melted to obtain an alloy ingot.

[0026] (3) Mechanical crushing: the alloy ingot material in step (2) is mechanically crushed, and the high plateau pressure vanadium-based hydrogen storage alloy is obtained by screening.

[0027] Further, the purity of the elemental metal in step (1) is ≥ 99.9wt%, including Ti source, Cr source, V source, Mo source and RE source, and the atomic ratio of the Ti source, Cr source, V source, Mo source and RE source is a:b:c:x:y, wherein 0.015≤a≤0.075, 0.075≤b≤0.255, 0.7≤c≤0.9, and a+b+c=1; 0.01≤x≤0.05, 0.01≤y≤0.05.

[0028] Further, the melting in step (2) is carried out in a vacuum arc furnace or a vacuum induction melting furnace under the protection of a protective gas, and the protective gas is an inert gas, which can be argon or an inert gas that does not react with the raw materials; after melting, the alloy is allowed to cool to room temperature with the copper crucible, it is turned over, and a new melting is carried out.

[0029] Preferably, the melting in step (2) is carried out in a vacuum arc furnace.

[0030] Further, the current for melting in step (2) is 150-240A, for example, 150A, 160A, 180A, 190A, 200A, 210A, 220A, 230A or 240A, etc., but not limited to the listed values, other values not listed in this range are also applicable, and preferably 180-220A.

[0031] Further, the single melting time for melting in step (2) is 60-150s, for example, 60s, 70s, 80s, 90s, 100s, 110s, 120s, 130s, 140s or 150s, etc., but not limited to the listed values, other values not listed in this range are also applicable, and preferably 60-110s.

[0032] Further, the number of times of melting in step (2) is 3-6 times, preferably 4-5 times.

[0033] Further, the alloy ingot material in step (2) includes a body-centered cubic cell phase.

[0034] It is worth noting that due to the strong adsorption of RE elements to O elements, a small amount of rare earth oxides is easily generated during the melting of the mixed material.

[0035] Further, the average particle size of the high plateau pressure vanadium-based hydrogen storage alloy obtained after screening in step (3) is 0.1-0.5 cm, for example, 0.1 cm, 0.2 cm, 0.3 cm, 0.4 cm or 0.5 cm, but not limited to the listed values, and other values not listed in the range are also applicable.

[0036] Further, the average particle size of the high plateau pressure vanadium-based hydrogen storage alloy obtained after screening in step (3) is 0.1-0.3 cm, for example, 0.1 cm, 0.15 cm, 0.2 cm, 0.25 cm or 0.3 cm, but not limited to the listed values, and other values not listed in the range are also applicable.

[0037] Further, the application of the high plateau pressure vanadium-based hydrogen storage alloy in hydrogen storage torches, fuel cell vehicles, forklifts or unmanned aerial vehicles.

[0038] Preferably, the high plateau pressure vanadium-based hydrogen storage alloy is used in hydrogen storage torches.

[0039] The present application has the following advantages:

[0040] 1. The high plateau pressure vanadium-based hydrogen storage alloy of the present application is based on Ti-Cr-V hydrogen storage alloy, with three metal elements in atomic percentage unit "1". By adding RE elements and controlling the content, the prepared vanadium-based hydrogen storage alloy can be directly activated at low temperature and has high plateau pressure, without the need for high-temperature or high-pressure activation process (on the one hand, oxidation may occur during preparation, and RE elements have high oxygen affinity, which can inhibit the oxidation of other elements, thereby achieving low-temperature activation of the entire material; on the other hand, RE elements increase the plateau pressure). By adding a molybdenum source and controlling the content, the hydrogen absorption and desorption plateau pressure of the vanadium-based alloy is improved, the prepared vanadium-based hydrogen storage alloy has fast hydrogen absorption and desorption kinetics, and the high plateau pressure vanadium hydrogen storage alloy provided by the present application has excellent performance, fast hydrogen absorption and desorption rate, and excellent activation performance. Specifically, at a low-temperature activation temperature of ≤25℃, the maximum hydrogen absorption of the optimal sample is ≥2.3wt%, the maximum hydrogen desorption is ≥2.2wt%, the plateau pressure is ≥2MPa, the hydrogen desorption time is 3min, and the cost is low.

[0041] 2. The preparation method of the present application is based on specific atomic proportions for batching, and by simple melting and mechanical crushing, a high plateau pressure vanadium-based hydrogen storage alloy can be obtained through screening, effectively reducing the activation temperature of the vanadium-based hydrogen storage alloy (activation temperature ≤25℃), improving the hydrogen absorption and desorption kinetics and maintaining high hydrogen storage and release capacity, and having the characteristics of simplicity, speed and effectiveness, facilitating large-scale popularization and use. In 20L min -1The high platform pressure vanadium-based hydrogen storage alloy prepared by the application has a hydrogen release time of up to 7.8 min at a large hydrogen release rate, and has a wide application prospect in the fields of hydrogen storage torches, fuel cell vehicles, forklifts or unmanned aerial vehicles, hydrogen storage and transportation. BRIEF DESCRIPTION OF DRAWINGS

[0042] In order to more clearly illustrate the technical solutions in the embodiments of the application or the prior art, the drawings needed to be used in the embodiments or the prior art description will be briefly introduced below. Obviously, the drawings in the following description are only some embodiments of the application, and other drawings can also be obtained by those skilled in the art without creative effort on the basis of these drawings.

[0043] Figure 1 The XRD pattern of the high platform pressure vanadium-based hydrogen storage alloy prepared in Example 1 of the application.

[0044] Figure 2 The SEM pattern of the high platform pressure vanadium-based hydrogen storage alloy prepared in Example 1 of the application.

[0045] Figure 3 The first hydrogen absorption kinetics pattern of the high platform pressure vanadium-based hydrogen storage alloy prepared in Example 1 of the application and the vanadium-based hydrogen storage alloy prepared in Comparative Examples 1-3.

[0046] Figure 4 The second hydrogen absorption kinetics pattern of the high platform pressure vanadium-based hydrogen storage alloy prepared in Example 1 of the application.

[0047] Figure 5 The hydrogen release kinetics pattern of the high platform pressure vanadium-based hydrogen storage alloy prepared in Example 1 of the application and the vanadium-based hydrogen storage alloy prepared in Comparative Examples 1-3.

[0048] Figure 6 The hydrogen release PCT pattern of the high platform pressure vanadium-based hydrogen storage alloy prepared in Example 1 of the application and the vanadium-based hydrogen storage alloy prepared in Comparative Examples 1-3.

[0049] Figure 7 The hydrogen release time of the high platform pressure vanadium-based hydrogen storage alloy prepared in Example 1 of the application at 20 L min -1

[0050] Figure 8 The hydrogen release kinetics and hydrogen release PCT curve of the high platform pressure vanadium-based hydrogen storage alloy prepared in Example 2 of the application.

[0051] Figure 9 The hydrogen release kinetics and hydrogen release PCT curve of the high platform pressure vanadium-based hydrogen storage alloy prepared in Example 3 of the application.

[0052] ​Figure 10 Hydrogen desorption kinetics and hydrogen desorption PCT curves of the high plateau pressure vanadium-based hydrogen storage alloy prepared for the present application embodiment 4.

[0053] Figure 11 Hydrogen desorption kinetics and hydrogen desorption PCT curves of the high plateau pressure vanadium-based hydrogen storage alloy prepared for the present application embodiment 5.

[0054] Figure 12 Hydrogen desorption kinetics and hydrogen desorption PCT curves of the high plateau pressure vanadium-based hydrogen storage alloy prepared for the present application embodiment 6. DETAILED DESCRIPTION

[0055] The technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the drawings in the embodiments of the present application. Obviously, the described embodiments are only a part of the embodiments of the present application, rather than all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those of ordinary skill in the art without creative effort belong to the scope of protection of the present application.

[0056] The raw materials used in the following embodiments of the present application are commercially available.

[0057] Embodiment 1

[0058] The present embodiment provides a high plateau pressure vanadium-based hydrogen storage alloy, which has an elemental composition of Ti 0.035 Cr 0.165 V 0.8 Mo 0.03 Ce 0.01 ;

[0059] The following preparation method is used for preparation:

[0060] (1) batching: weighing elemental metals Ti 0.035 mol, Cr 0.165 mol, V 0.8 mol, Mo 0.03 mol, and Ce 0.01 mol with a purity of ≥99.9wt%, and batching to obtain a mixture;

[0061] (2) melting: loading the mixture of step (1) into a water-cooled copper mold of a non-consumable vacuum arc furnace, and then placing it into a vacuum arc furnace for melting under the protection of argon, the current in the melting is 200A, the single melting time is 100s, after single melting, the alloy is allowed to cool to room temperature with the copper crucible, it is turned over, and a new single melting is carried out, and the repeated melting is carried out 4 times to obtain an alloy ingot; wherein the alloy ingot comprises a body-centered cubic cell phase;

[0062] (3) Mechanical crushing: the alloy ingot material in step (2) is mechanically crushed, and the high plateau pressure vanadium-based hydrogen storage alloy with an average particle size of 0.3 cm is obtained through screening.

[0063] Example 2

[0064] This example provides a high plateau pressure vanadium-based hydrogen storage alloy, the element composition of the high plateau pressure vanadium-based hydrogen storage alloy is Ti 0.035 Cr 0.165 V 0.8 Mo 0.03 Ce 0.02 ;

[0065] The following preparation method is used for preparation:

[0066] (1) Dosing: the elemental metals Ti 0.035 mol, Cr 0.165 mol, V 0.8 mol, Mo 0.03 mol, and Ce 0.02 mol with a purity of ≥99.9wt% are weighed according to the atomic ratio, and dosing is performed to obtain a mixture;

[0067] (2) Melting: the mixture in step (1) is loaded into a water-cooled copper mold of a non-consumable vacuum arc furnace, and then is placed into a vacuum arc furnace for melting under the protection of argon gas, the current in the melting is 200A, the single melting time is 100s, after single melting, the alloy is allowed to cool to room temperature with the copper crucible, it is turned over, and new single melting is performed, and the repeated melting is performed 4 times to obtain an alloy ingot material; wherein, the alloy ingot material includes a body-centered cubic cell phase;

[0068] (3) Mechanical crushing: the alloy ingot material in step (2) is mechanically crushed, and the high plateau pressure vanadium-based hydrogen storage alloy with an average particle size of 0.3 cm is obtained through screening.

[0069] Example 3

[0070] This example provides a high plateau pressure vanadium-based hydrogen storage alloy, the element composition of the high plateau pressure vanadium-based hydrogen storage alloy is Ti 0.035 Cr 0.165 V 0.8 Mo 0.01 Ce 0.01 ;

[0071] The following preparation method is used for preparation:

[0072] (1) Dosing: the elemental metals Ti 0.035 mol, Cr 0.165 mol, V 0.8 mol, Mo 0.01 mol, and Ce 0.01 mol with a purity of ≥99.9wt% are weighed according to the atomic ratio, and dosing is performed to obtain a mixture;

[0073] (2) Melting: the mixture of step (1) is loaded into a water-cooled copper mold of a non-consumable vacuum arc furnace, and then placed into a vacuum arc furnace for melting under the protection of argon, the current in the melting is 200 A, the single melting time is 100 s, after single melting, the alloy is allowed to cool to room temperature with the copper crucible, it is turned over, and a new single melting is carried out, and the melting is repeated for 4 times to obtain an alloy ingot; wherein the alloy ingot comprises a body-centered cubic cell phase;

[0074] (3) Mechanical crushing: the alloy ingot of step (2) is mechanically crushed, and the high plateau pressure vanadium-based hydrogen storage alloy with an average particle size of 0.3 cm is obtained through screening.

[0075] Example 4

[0076] The embodiment provides a high plateau pressure vanadium-based hydrogen storage alloy, and the high plateau pressure vanadium-based hydrogen storage alloy has an element composition of Ti 0.035 Cr 0.165 V 0.8 Mo 0.03 Ce 0.05 ;

[0077] The following preparation method is used for preparation:

[0078] (1) Dosing: the pure metals Ti 0.035 mol, Cr 0.165 mol, V 0.8 mol, Mo 0.03 mol and Ce 0.05 mol with a purity of ≥99.9wt% are weighed according to the atomic ratio and dosed to obtain a mixture;

[0079] (2) Melting: the mixture of step (1) is loaded into a water-cooled copper mold of a non-consumable vacuum arc furnace, and then placed into a vacuum arc furnace for melting under the protection of argon, the current in the melting is 200 A, the single melting time is 100 s, after single melting, the alloy is allowed to cool to room temperature with the copper crucible, it is turned over, and a new single melting is carried out, and the melting is repeated for 4 times to obtain an alloy ingot; wherein the alloy ingot comprises a body-centered cubic cell phase;

[0080] (3) Mechanical crushing: the alloy ingot of step (2) is mechanically crushed, and the high plateau pressure vanadium-based hydrogen storage alloy with an average particle size of 0.3 cm is obtained through screening.

[0081] Example 5

[0082] The embodiment provides a high plateau pressure vanadium-based hydrogen storage alloy, and the high plateau pressure vanadium-based hydrogen storage alloy has an element composition of Ti 0.035 Cr 0.165 V 0.8 Mo 0.05 Ce 0.01 ;

[0083] The high plateau pressure vanadium-based hydrogen storage alloy is prepared by the following preparation method:

[0084] (1) batching: taking elemental metals Ti 0.035 mol, Cr 0.165 mol, V 0.8 mol, Mo 0.05 mol, Ce 0.01 mol with a purity of ≥99.9wt% according to the atomic ratio, and batching to obtain a mixed material;

[0085] (2) melting: the mixed material in step (1) is loaded into a water-cooled copper mold of a non-consumable vacuum arc furnace, and then is placed into a vacuum arc furnace for melting under the protection of argon, the current in the melting is 200 A, the single melting time is 100 s, after single melting, the alloy is allowed to cool to room temperature with the copper crucible, it is turned over, and then a new single melting is carried out, and the repeated melting is carried out for 4 times to obtain an alloy ingot material; wherein the alloy ingot material comprises a body-centered cubic cell phase;

[0086] (3) mechanical crushing: the alloy ingot material in step (2) is mechanically crushed, and sieving is carried out to obtain the high plateau pressure vanadium-based hydrogen storage alloy with an average particle size of 0.3 cm.

[0087] Example 6

[0088] The embodiment provides a high plateau pressure vanadium-based hydrogen storage alloy, the element composition of the high plateau pressure vanadium-based hydrogen storage alloy is Ti 0.035 Cr 0.165 V 0.8 Mo 0.03 La 0.01 ;

[0089] The high plateau pressure vanadium-based hydrogen storage alloy is prepared by the following preparation method:

[0090] (1) batching: taking elemental metals Ti 0.035 mol, Cr 0.165 mol, V 0.8 mol, Mo 0.03 mol, La 0.01 mol with a purity of ≥99.9wt% according to the atomic ratio, and batching to obtain a mixed material;

[0091] (2) melting: the mixed material in step (1) is loaded into a water-cooled copper mold of a non-consumable vacuum arc furnace, and then is placed into a vacuum arc furnace for melting under the protection of argon, the current in the melting is 200 A, the single melting time is 100 s, after single melting, the alloy is allowed to cool to room temperature with the copper crucible, it is turned over, and then a new single melting is carried out, and the repeated melting is carried out for 4 times to obtain an alloy ingot material; wherein the alloy ingot material comprises a body-centered cubic cell phase;

[0092] (3) mechanical crushing: the alloy ingot material in step (2) is mechanically crushed, and sieving is carried out to obtain the high plateau pressure vanadium-based hydrogen storage alloy with an average particle size of 0.3 cm.

[0093] Example 7

[0094] The embodiment provides a high plateau pressure vanadium-based hydrogen storage alloy, and an element composition of the high plateau pressure vanadium-based hydrogen storage alloy is Ti 0.035 Cr 0.165 V 0.8 Mo 0.03 Y 0.01 ;

[0095] The high plateau pressure vanadium-based hydrogen storage alloy is prepared by the following preparation method:

[0096] (1) batching: according to atomic proportions, pure metal Ti 0.035 mol, Cr 0.165 mol, V 0.8 mol, Mo 0.03 mol and Y 0.01 mol with a purity of greater than or equal to 99.9% by weight are weighed and batched to obtain a mixture;

[0097] (2) melting: the mixture in step (1) is loaded into a water-cooled copper mold of a non-consumable vacuum arc furnace, and then is placed into a vacuum arc furnace for melting under the protection of argon, the current in the melting is 200 A, the single melting time is 100 s, after single melting, the alloy is allowed to cool to room temperature with the copper crucible, the alloy is turned over, and then a new single melting is carried out, and the repeated melting is carried out 4 times to obtain an alloy ingot; wherein the alloy ingot comprises a body-centered cubic cell phase;

[0098] (3) mechanical crushing: the alloy ingot in step (2) is mechanically crushed, and the high plateau pressure vanadium-based hydrogen storage alloy with an average particle size of 0.3 cm is obtained through screening.

[0099] Example 8

[0100] The embodiment provides a high plateau pressure vanadium-based hydrogen storage alloy, and an element composition of the high plateau pressure vanadium-based hydrogen storage alloy is Ti 0.015 Cr 0.085 V 0.9 Mo 0.03 Ce 0.01 ;

[0101] The high plateau pressure vanadium-based hydrogen storage alloy is prepared by the following preparation method:

[0102] (1) batching: according to atomic proportions, pure metal Ti 0.015 mol, Cr 0.085 mol, V 0.9 mol, Mo 0.03 mol and Ce 0.01 mol with a purity of greater than or equal to 99.9% by weight are weighed and batched to obtain a mixture;

[0103] (2) Melting: the mixture of step (1) is placed into a vacuum induction furnace for melting under the protection of argon, the current in the melting is 150 A, the single melting time is 150 s, after single melting, the alloy is allowed to cool to room temperature with the copper crucible, it is turned over, and a new single melting is carried out, and the melting is repeated for 3 times to obtain an alloy ingot; wherein the alloy ingot comprises a body-centered cubic cell phase;

[0104] (3) Mechanical crushing: the alloy ingot of step (2) is mechanically crushed, and the high plateau pressure vanadium-based hydrogen storage alloy with an average particle size of 0.1 cm is obtained through screening.

[0105] Example 9

[0106] The embodiment provides a high plateau pressure vanadium-based hydrogen storage alloy, and the element composition of the high plateau pressure vanadium-based hydrogen storage alloy is Ti 0.075 Cr 0.225 V 0.7 Mo 0.03 Ce 0.01 ;

[0107] The following preparation method is used for preparation:

[0108] (1) Dosing: the elemental metals Ti 0.075 mol, Cr 0.225 mol, V 0.7 mol, Mo 0.03 mol and Ce 0.01 mol with a purity of ≥99.9wt% are weighed according to the atomic ratio and dosed to obtain a mixture;

[0109] (2) Melting: the mixture of step (1) is placed into a vacuum induction furnace for melting under the protection of argon, the current in the melting is 240 A, the single melting time is 60 s, after single melting, the alloy is allowed to cool to room temperature with the copper crucible, it is turned over, and a new single melting is carried out, and the melting is repeated for 5 times to obtain an alloy ingot; wherein the alloy ingot comprises a body-centered cubic cell phase;

[0110] (3) Mechanical crushing: the alloy ingot of step (2) is mechanically crushed, and the high plateau pressure vanadium-based hydrogen storage alloy with an average particle size of 0.5 cm is obtained through screening.

[0111] Comparative Example 1

[0112] The comparative example provides a vanadium-based hydrogen storage alloy, and the element composition of the vanadium-based hydrogen storage alloy is Ti 0.035 Cr 0.165 V 0.8 Ce 0.01 ;

[0113] The following preparation method is used for preparation:

[0114] (1)Batching: elemental metals with purity ≥ 99.9wt% of Ti 0.035mol, Cr 0.165mol, V 0.8mol, Ce 0.01mol were weighed according to the atomic ratio and batched to obtain a mixture;

[0115] (2) Melting: the mixture of step (1) was loaded into a water-cooled copper mold of a non-consumable vacuum arc furnace, and then was placed into a vacuum arc furnace for melting under the protection of argon. The current in the melting was 200A, and the single melting time was 100s. After single melting, the alloy was allowed to cool to room temperature with the copper crucible, which was then turned over for a new single melting. The above process was repeated for 4 times to obtain an alloy ingot. The alloy ingot comprises a body-centered cubic cell phase.

[0116] (3) Mechanical crushing: the alloy ingot of step (2) was mechanically crushed, and the high plateau pressure vanadium-based hydrogen storage alloy with an average particle size of 0.3cm was obtained by screening.

[0117] Comparative Example 2

[0118] This comparative example provides a vanadium-based hydrogen storage alloy, which has an elemental composition of Ti 0.035 Cr 0.165 V 0.8 Mo 0.03 ;

[0119] The following preparation method was used to prepare:

[0120] (1)Batching: elemental metals with purity ≥ 99.9wt% of Ti 0.035mol, Cr 0.165mol, V 0.8mol, Mo 0.03mol were weighed according to the atomic ratio and batched to obtain a mixture;

[0121] (2) Melting: the mixture of step (1) was loaded into a water-cooled copper mold of a non-consumable vacuum arc furnace, and then was placed into a vacuum arc furnace for melting under the protection of argon. The current in the melting was 200A, and the single melting time was 100s. After single melting, the alloy was allowed to cool to room temperature with the copper crucible, which was then turned over for a new single melting. The above process was repeated for 4 times to obtain an alloy ingot. The alloy ingot comprises a body-centered cubic cell phase.

[0122] (3) Mechanical crushing: the alloy ingot of step (2) was mechanically crushed, and the high plateau pressure vanadium-based hydrogen storage alloy with an average particle size of 0.3cm was obtained by screening.

[0123] Comparative Example 3

[0124] This comparative example provides a vanadium-based hydrogen storage alloy, which has an elemental composition of Ti 0.035 Cr 0.165V 0.8 ;

[0125] The high plateau pressure vanadium-based hydrogen storage alloy is prepared by the following preparation method:

[0126] (1) batching: taking elemental metals Ti 0.035 mol, Cr 0.165 mol, V 0.8 mol with a purity of ≥99.9wt% according to the atomic ratio, and batching to obtain a mixed material;

[0127] (2) melting: the mixed material in step (1) is loaded into a water-cooled copper mold of a non-consumable vacuum arc furnace, and then is placed into a vacuum arc furnace for melting under the protection of argon, the current in the melting is 200 A, the single melting time is 100 s, after single melting, the alloy is allowed to cool to room temperature with the copper crucible, it is turned over, and a new single melting is carried out, and the melting is repeated for 4 times to obtain an alloy ingot material; wherein the alloy ingot material comprises a body-centered cubic cell phase;

[0128] (3) mechanical crushing: the alloy ingot material in step (2) is mechanically crushed, and the high plateau pressure vanadium-based hydrogen storage alloy with an average particle size of 0.3 cm is obtained through screening.

[0129] Comparative Example 4

[0130] The present comparative example provides a vanadium-based hydrogen storage alloy, the element composition of the vanadium-based hydrogen storage alloy is Ti 0.035 Cr 0.165 V 0.8 Mo 0.01 ;

[0131] The high plateau pressure vanadium-based hydrogen storage alloy is prepared by the following preparation method:

[0132] (1) batching: taking elemental metals Ti 0.035 mol, Cr 0.165 mol, V 0.8 mol, Mo 0.01 mol with a purity of ≥99.9wt% according to the atomic ratio, and batching to obtain a mixed material;

[0133] (2) melting: the mixed material in step (1) is loaded into a water-cooled copper mold of a non-consumable vacuum arc furnace, and then is placed into a vacuum arc furnace for melting under the protection of argon, the current in the melting is 200 A, the single melting time is 100 s, after single melting, the alloy is allowed to cool to room temperature with the copper crucible, it is turned over, and a new single melting is carried out, and the melting is repeated for 4 times to obtain an alloy ingot material; wherein the alloy ingot material comprises a body-centered cubic cell phase;

[0134] (3) mechanical crushing: the alloy ingot material in step (2) is mechanically crushed, and the high plateau pressure vanadium-based hydrogen storage alloy with an average particle size of 0.3 cm is obtained through screening.

[0135] Comparative Example 5

[0136] The present comparative example provides a vanadium-based hydrogen storage alloy, which has an elemental composition of Ti 0.035 Cr 0.165 V 0.8 Mo 0.02 ;

[0137] The vanadium-based hydrogen storage alloy is prepared by the following preparation method:

[0138] (1) batching: elemental metals Ti 0.035 mol, Cr 0.165 mol, V 0.8 mol, and Mo 0.02 mol with a purity of ≥99.9wt% are weighed according to the atomic ratio and batched to obtain a mixture;

[0139] (2) melting: the mixture in step (1) is loaded into a water-cooled copper mold of a non-consumable vacuum arc furnace, and then is placed into a vacuum arc furnace for melting under the protection of argon gas, the current in the melting is 200 A, the single melting time is 100 s, after single melting, the alloy is allowed to cool to room temperature with the copper crucible, it is turned over, and a new single melting is carried out, and the melting is repeated for 4 times to obtain an alloy ingot; wherein, the alloy ingot comprises a body-centered cubic cell phase;

[0140] (3) mechanical crushing: the alloy ingot in step (2) is mechanically crushed, and sieved to obtain the high plateau pressure vanadium-based hydrogen storage alloy with an average particle size of 0.3 cm.

[0141] Comparative Example 6

[0142] The present comparative example provides a vanadium-based hydrogen storage alloy, which has an elemental composition of Ti 0.035 Cr 0.165 V 0.8 Mo 0.025 ;

[0143] The vanadium-based hydrogen storage alloy is prepared by the following preparation method:

[0144] (1) batching: elemental metals Ti 0.035 mol, Cr 0.165 mol, V 0.8 mol, and Mo 0.02 mol with a purity of ≥99.9wt% are weighed according to the atomic ratio and batched to obtain a mixture;

[0145] (2) melting: the mixture in step (1) is loaded into a water-cooled copper mold of a non-consumable vacuum arc furnace, and then is placed into a vacuum arc furnace for melting under the protection of argon gas, the current in the melting is 200 A, the single melting time is 100 s, after single melting, the alloy is allowed to cool to room temperature with the copper crucible, it is turned over, and a new single melting is carried out, and the melting is repeated for 4 times to obtain an alloy ingot; wherein, the alloy ingot comprises a body-centered cubic cell phase;

[0146] (3) Mechanical crushing: the alloy ingot material in step (2) is mechanically crushed, and the high plateau pressure vanadium-based hydrogen storage alloy with an average particle size of 0.3 cm is obtained through screening.

[0147] Comparative Example 7

[0148] The present comparative example provides a high plateau pressure vanadium-based hydrogen storage alloy, the elemental composition of which is Ti 0.035 Cr 0.165 V 0.8 Mo 0.05 ;

[0149] The following preparation method is used for preparation:

[0150] (1) batching: the pure metal Ti 0.035 mol, Cr 0.165 mol, V 0.8 mol, and Mo 0.05 mol with a purity of ≥99.9wt% are weighed according to the atomic ratio, and are batched to obtain a mixture;

[0151] (2) melting: the mixture in step (1) is loaded into a water-cooled copper mold of a non-consumable vacuum arc furnace, and then is placed into a vacuum arc furnace for melting under the protection of argon. The current in the melting is 200 A, and the single melting time is 100 s. After single melting, the alloy is allowed to cool to room temperature with the copper crucible, is turned over, and then is subjected to a new single melting. The above-mentioned melting is repeated for 4 times to obtain an alloy ingot material. The alloy ingot material comprises a body-centered cubic cell phase;

[0152] (3) mechanical crushing: the alloy ingot material in step (2) is mechanically crushed, and the high plateau pressure vanadium-based hydrogen storage alloy with an average particle size of 0.3 cm is obtained through screening.

[0153] The high plateau pressure vanadium-based hydrogen storage alloy prepared in Example 1 is subjected to structure and morphology analysis, and the results are shown in Figure 1 and Figure 2 The XRD results show that the main phase structure of the alloy is a BCC phase, and some secondary cerium oxide components are produced. The SEM results also show that the alloy is composed of a gray matrix BCC phase and a white cerium oxide phase.

[0154] The high plateau pressure vanadium-based hydrogen storage alloy prepared in Example 1 and the vanadium-based hydrogen storage alloys prepared in Comparative Examples 1-3 are subjected to hydrogen absorption and desorption performance tests at 25℃, and the first hydrogen absorption kinetics curves are obtained, as shown in Table 1 and Figure 3 From Figure 3 it can be known that the addition of rare earth elements can significantly improve the activation capacity of the alloy, so that the alloy can absorb hydrogen without high-temperature activation at 400℃.

[0155] The second hydrogen absorption kinetics curve of the high plateau pressure vanadium-based hydrogen storage alloy at 25℃ is shown in Table 1 andFigure 4 As shown in the figure, the alloy reaches the maximum hydrogen absorption amount at about 8 min, indicating that Example 1 has rapid hydrogen absorption kinetics.

[0156] The hydrogen desorption kinetics of the high plateau pressure vanadium-based hydrogen storage alloy at 25°C is shown in Table 1 and Figure 5 As shown in the figure, increasing the molybdenum element can significantly improve the hydrogen absorption and desorption rate of the alloy, and the effective hydrogen desorption amount of these samples exceeds 1.91wt%, and the effective hydrogen desorption amount of Example 1 reaches 2.28wt%, and the hydrogen desorption only takes 2.98 min, about 3 min.

[0157] The hydrogen desorption PCT curve of the high plateau pressure vanadium-based hydrogen storage alloy at 25°C is shown in Table 1 and Figure 6 As shown in the figure, whether increasing the rare earth element or the molybdenum element increases the hydrogen desorption plateau pressure of the alloy, so that the alloy can quickly desorb hydrogen.

[0158] The hydrogen desorption time of the high plateau pressure vanadium-based hydrogen storage alloy prepared in Example 1 at a large hydrogen desorption rate of 20L min -1 is measured, as shown in Figure 7 It can be seen that the hydrogen desorption time of the high plateau pressure vanadium-based hydrogen storage alloy at a large hydrogen desorption rate of 20L min -1 is as high as 7.8 min, making it possible for the hydrogen storage alloy to be applied in the fields of hydrogen storage torch, fuel cell vehicle, forklift or unmanned aerial vehicle, hydrogen storage and transportation.

[0159] The hydrogen storage performance of the high plateau pressure vanadium-based hydrogen storage alloy prepared in Example 1 is evaluated, and the test results are shown in Table 1. The maximum hydrogen absorption amount of the alloy is 2.34wt%, the hydrogen desorption amount is 2.28wt%, the hydrogen desorption plateau pressure is 2.17MPa, and the hydrogen desorption time is 2.98min.

[0160] The hydrogen storage performance of the high plateau pressure vanadium-based hydrogen storage alloy prepared in Example 2 is evaluated, and the test results are shown in Table 1 and Figure 8 As shown in the figure, the maximum hydrogen absorption amount of the alloy is 1.95wt%, the effective hydrogen desorption amount is 1.73wt%, the hydrogen desorption plateau pressure is 2.8MPa, and the hydrogen desorption time is 2.8min.

[0161] The hydrogen storage performance of the high plateau pressure vanadium-based hydrogen storage alloy prepared in Example 3 is evaluated, and the test results are shown in Table 1 and Figure 9 As shown in the figure, the maximum hydrogen absorption amount of the alloy is 2.53wt%, the effective hydrogen desorption amount is 2.41wt%, the hydrogen desorption plateau pressure is 1.52MPa, and the hydrogen desorption time is 4.3min.

[0162] The hydrogen storage performance of the high plateau pressure vanadium-based hydrogen storage alloy prepared in Example 4 is evaluated, and the test results are shown in Table 1 and Figure 10As shown in Table 1, the maximum hydrogen absorption amount of the alloy is 2.21wt%, the effective hydrogen release amount is 2.1wt%, the hydrogen release plateau pressure is 3.38MPa, and the hydrogen release time is 2.6min.

[0163] The hydrogen storage performance of the high plateau pressure vanadium-based hydrogen storage alloy prepared in Example 5 was evaluated, and the test results are shown in Table 1 and Figure 11 As shown in Table 1, the maximum hydrogen absorption amount of the alloy is 1.85wt%, the effective hydrogen release amount is 1.63wt%, the hydrogen release plateau pressure is 4.3MPa, and the hydrogen release time is 2.2min.

[0164] The hydrogen storage performance of the high plateau pressure vanadium-based hydrogen storage alloy prepared in Example 6 was evaluated, and the test results are shown in Table 1 and Figure 12 As shown in Table 1, the maximum hydrogen absorption amount of the alloy is 2.28wt%, the effective hydrogen release amount is 2.17wt%, the hydrogen release plateau pressure is 1.83MPa, and the hydrogen release time is 3.8min.

[0165] The hydrogen storage performance of the high plateau pressure vanadium-based hydrogen storage alloy prepared in Example 7 was evaluated, and the test results are shown in Table 1, the maximum hydrogen absorption amount of the alloy is 2.54wt%, the effective hydrogen release amount is 2.42wt%, the hydrogen release plateau pressure is 1.83MPa, and the hydrogen release time is 3.9min.

[0166] The hydrogen storage performance of the high plateau pressure vanadium-based hydrogen storage alloy prepared in Example 8 was evaluated, and the test results are shown in Table 1, the maximum hydrogen absorption amount of the alloy is 2.55wt%, the effective hydrogen release amount is 2.41wt%, the hydrogen release plateau pressure is 2.2MPa, and the hydrogen release time is 2.95min.

[0167] The hydrogen storage performance of the high plateau pressure vanadium-based hydrogen storage alloy prepared in Example 9 was evaluated, and the test results are shown in Table 1, the maximum hydrogen absorption amount of the alloy is 2.52wt%, the effective hydrogen release amount is 2.40wt%, the hydrogen release plateau pressure is 1.75MPa, and the hydrogen release time is 3.96min.

[0168] The hydrogen storage performance of the vanadium-based hydrogen storage alloy prepared in Comparative Example 1 was evaluated, and the test results are shown in Table 1, the maximum hydrogen absorption amount of the alloy is 2.27wt%, the effective hydrogen release amount is 1.91wt%, the hydrogen release plateau pressure is 1.45MPa, and the hydrogen release time is 4.7min.

[0169] The hydrogen storage performance of the high plateau pressure vanadium-based hydrogen storage alloy prepared in Comparative Example 2 was evaluated, and the test results are shown in Table 1, after high-temperature activation at 400℃, the maximum hydrogen absorption amount of the alloy is 3.7wt%, the effective hydrogen release amount is 2.53wt%, the hydrogen release plateau pressure is 2.37MPa, and the hydrogen release time is 3.2min.

[0170] The high plateau pressure vanadium-based hydrogen storage alloy prepared from the Comparative Example 3 was evaluated for hydrogen storage performance, and the test results are shown in Table 1. After high temperature activation at 400°C, the maximum hydrogen absorption amount of the alloy was 3.58wt%, the effective hydrogen release amount was 2.21wt%, the hydrogen release plateau pressure was 1.39MPa, and the hydrogen release time was 4.6min.

[0171] The high plateau pressure vanadium-based hydrogen storage alloy prepared from the Comparative Example 4 was evaluated for hydrogen storage performance, and the test results are shown in Table 1. After high temperature activation at 400°C, the maximum hydrogen absorption amount of the alloy was 3.73wt%, the effective hydrogen release amount was 2.32wt%, the hydrogen release plateau pressure was 1.52MPa, and the hydrogen release time was 4.6min.

[0172] The high plateau pressure vanadium-based hydrogen storage alloy prepared from the Comparative Example 5 was evaluated for hydrogen storage performance, and the test results are shown in Table 1. After high temperature activation at 400°C, the maximum hydrogen absorption amount of the alloy was 3.56wt%, the effective hydrogen release amount was 2.2wt%, the hydrogen release plateau pressure was 1.82MPa, and the hydrogen release time was 4.0min.

[0173] The high plateau pressure vanadium-based hydrogen storage alloy prepared from the Comparative Example 6 was evaluated for hydrogen storage performance, and the test results are shown in Table 1. After high temperature activation at 400°C, the maximum hydrogen absorption amount of the alloy was 3.61wt%, the effective hydrogen release amount was 2.52wt%, the hydrogen release plateau pressure was 2.27MPa, and the hydrogen release time was 3.6min.

[0174] The high plateau pressure vanadium-based hydrogen storage alloy prepared from the Comparative Example 7 was evaluated for hydrogen storage performance, and the test results are shown in Table 1. After high temperature activation at 400°C, the maximum hydrogen absorption amount of the alloy was 2.13wt%, the effective hydrogen release amount was 1.50wt%, the hydrogen release plateau pressure was 4.44MPa, and the hydrogen release time was 2.0min.

[0175] The activation temperature, maximum hydrogen storage amount, effective hydrogen release amount, hydrogen release plateau pressure, and hydrogen release kinetics time of the high plateau pressure vanadium-based hydrogen storage alloy prepared from Examples 1-9 and the vanadium-based hydrogen storage alloy prepared from Comparative Examples 1-7 were determined, and the determination results are shown in Table 1.

[0176] Table 1 Hydrogen storage performance of rare earth hydrogen storage alloys prepared from Examples 1-9 and Comparative Examples 1-7

[0177]

[0178] Note: Example 1 Ti 0.035 Cr 0.165 V 0.8 Mo 0.03 Ce 0.01 ; Example 2 Ti 0.035 Cr 0.165 V 0.8Mo 0.03 Ce 0.02 ; Example 3 Ti 0.035 Cr 0.165 V 0.8 Mo 0.01 Ce 0.01 ; Example 4 Ti 0.035 Cr 0.165 V 0.8 Mo 0.03 Ce 0.05 ; Example 5 Ti 0.035 Cr 0.165 V 0.8 Mo 0.05 Ce 0.01 ; Example 6 Ti 0.035 Cr 0.165 V 0.8 Mo 0.03 La 0.01 ; Example 7 Ti 0.035 Cr 0.165 V 0.8 Mo 0.03 Y 0.01 ; Example 8 Ti 0.015 Cr 0.085 V 0.9 Mo 0.03 Ce 0.01 ; Example 9 Ti 0.075 Cr 0.225 V 0.7 Mo 0.03 Ce 0.01 ; Comparative Example 1 Ti 0.035 Cr 0.165 V 0.8 Ce 0.01 ; Comparative Example 2 Ti 0.035 Cr 0.165 V 0.8 Mo 0.03 ; Comparative Example 3 Ti 0.035 Cr 0.165 V 0.8 ; Comparative Example 4 Ti 0.035 Cr 0.165 V 0.8 Mo 0.01 ; Comparative Example 5 Ti 0.035 Cr 0.165 V 0.8 Mo 0.02 ; Comparative Example 6 Ti 0.035 Cr 0.165 V 0.8 Mo 0.025 ; Comparative Example 7 Ti 0.035 Cr 0.165 V 0.8Mo 0.05

[0179] Examples 1-9 adjust the microstructure of the alloy by regulating the content of molybdenum element or rare earth element, adjust the plateau pressure of the alloy to different degrees, and significantly improve the hydrogen absorption and desorption rate of the alloy. Comparative Example 1 does not increase the molybdenum element in the preparation process, so that the plateau pressure of the obtained hydrogen storage alloy is relatively low, which affects the hydrogen absorption and desorption rate of the alloy, and makes the hydrogen desorption kinetic time longer; Comparative Examples 2, 4-7 do not increase the cerium element in the preparation process, so that the obtained hydrogen storage alloy needs to be activated at high temperature for multiple times to absorb hydrogen; Comparative Example 3 does not increase the molybdenum element and the cerium element in the preparation process, so that the plateau pressure of the obtained hydrogen storage alloy is low, and the hydrogen storage alloy needs to be activated at high temperature for multiple times to absorb hydrogen, and the hydrogen absorption and desorption rate of the alloy is affected.

[0180] From the above examples and comparative examples, it can be seen that the preparation method described in the present application improves the hydrogen storage performance by using a specific raw material ratio, and significantly improves the hydrogen absorption and desorption kinetics, activation performance, hydrogen absorption rate and cycle life of the alloy. The alloy does not need to be activated at high temperature under optimal conditions, the maximum hydrogen absorption amount of the hydrogen storage alloy in Example 1 is not less than 2.34wt%, the effective hydrogen desorption amount is not less than 2.28wt%, the hydrogen desorption plateau pressure is as high as 2.17MPa, the hydrogen desorption kinetic time is not more than 3min, and the use temperature is lower than 25℃. The preparation method has a simple process flow, low cost, is conducive to large-scale production, and has good industrial application prospect.

[0181] The above only describes the preferred embodiments of the present application and should not be used to limit the present application. Any modification, equivalent replacement, improvement, etc. made within the spirit and principles of the present application should be included in the protection scope of the present application.

Claims

1. A high-platform-pressure vanadium-based hydrogen storage alloy, characterized in that: The high-platform vanadium-based hydrogen storage alloy has an elemental composition of Ti. a Cr b V c Mo x RE y , wherein RE is at least one of La, Ce or Y, 0.015≤a≤0.075, 0.075≤b≤0.255, 0.7≤c≤0.9, and a+b+c=1; 0.01≤x≤0.05, 0.01≤y≤0.05; the atomic ratio of a to b is (1~3):(3~17); when the activation temperature of the high plateau pressure vanadium-based hydrogen storage alloy is ≤25 ℃, the plateau pressure is ≥2 MPa.

2. The preparation method of the high-platform-pressure vanadium-based hydrogen storage alloy according to claim 1, characterized in that, The elemental metals are weighed, mixed, and smelted into alloy ingots. After mechanical crushing and screening, a high-pressure vanadium-based hydrogen storage alloy is obtained.

3. The method for preparing high-platform-pressure vanadium-based hydrogen storage alloy according to claim 2, characterized in that: The purity of the elemental metal is ≥99.9wt%, including Ti, Cr, V, Mo and RE, with the atomic ratio of Ti, Cr, V, Mo and RE being a:b:c:x:y, where 0.015≤a≤0.075, 0.075≤b≤0.255, 0.7≤c≤0.9, and a+b+c=1; 0.01≤x≤0.05, 0.01≤y≤0.

05.

4. The method for preparing high-platform-pressure vanadium-based hydrogen storage alloy according to claim 2, characterized in that: The melting is carried out in a vacuum electric arc furnace or a vacuum induction melting furnace under the protection of a protective gas, which is an inert gas.

5. The method for preparing high-platform-pressure vanadium-based hydrogen storage alloy according to claim 4, characterized in that: The current for melting is 150-240 A, the melting time for a single melting session is 60-150 s, and the number of melting sessions is 3-6.

6. The method for preparing high-platform-pressure vanadium-based hydrogen storage alloy according to claim 2, characterized in that: The alloy ingot comprises a body-centered cubic phase.

7. The method for preparing high-platform-pressure vanadium-based hydrogen storage alloy according to claim 2, characterized in that: The average particle size of the high-platform pressure vanadium-based hydrogen storage alloy obtained after sieving is 0.1~0.5 cm.

8. The application of the high-platform-pressure vanadium-based hydrogen storage alloy of claim 1 in hydrogen storage torches, fuel cell vehicles, forklifts, or drones.

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