AB5 type multi-element doped modified hydrogen storage material easy to activate as well as preparation method and application of AB5 type multi-element doped modified hydrogen storage material

Abstract

The invention relates to an easy-to-activate AB5 type multi-element doped modified hydrogen storage material and a preparation method and application thereof, the chemical general formula of the hydrogen storage material is LaxCeyNdzNiaFebMnc, x + y + z = 1, x is greater than or equal to 0.5, y is greater than or equal to 0 and less than or equal to 0.5, and z is greater than or equal to 0 and less than or equal to 0.5; a + b + c = 5, a > = 4, 0 < = b < = 1, 0 < = c < = 1, and at least two of y, z, b and c are not equal to 0. Compared with the prior art, the single-phase AB5 type hydrogen storage alloy with a hexagonal crystal form is prepared by synergistically replacing A site (La) by Ce / Nd and replacing B site (Ni) by Fe / Mn according to a specific proportion, the alloy has relatively high hydrogen storage capacity and rapid hydrogen absorption and desorption dynamic performance, the hysteresis of a hydrogen absorption and desorption platform is obviously improved, and rapid hydrogen absorption and the like can be completed without hydrogen absorption and desorption activation.

Description

Technical Field

[0001] This invention belongs to the field of hydrogen storage material technology, and relates to an easily activated AB5-type multi-component doped modified hydrogen storage material, its preparation method and application. Background Technology

[0002] Hydrogen energy, as a clean and efficient secondary energy carrier, is considered one of the key pathways to achieving carbon neutrality. In the entire hydrogen energy chain of production, storage, transportation, and utilization, safe, efficient, and economical hydrogen storage technology is the bottleneck restricting its large-scale application. Among various hydrogen storage methods, solid-state hydrogen storage based on metal hydrides has become an important development direction for stationary hydrogen storage and specific mobile scenarios due to its advantages such as high volumetric hydrogen storage density, low operating pressure, and good safety. Among the many types of hydrogen storage alloys, LaNi5 alloy is a classic AB5-type hydrogen storage material. LaNi5 can undergo a reversible reaction with hydrogen near room temperature (LaNi5 + 3H2 ⇌ LaNi5H6), with a hydrogen storage capacity of approximately 1.4 wt.%, and possesses good kinetic performance and a moderate plateau pressure. These characteristics have enabled its practical application in nickel-metal hydride (Ni-MH) battery anode materials, hydrogen isotope separation, and early small-scale hydrogen storage devices.

[0003] However, with the continuous expansion of hydrogen energy applications and the increasing demands on material performance, the inherent defects of the basic LaNi5 alloy have become increasingly prominent, severely limiting its wider and more economical commercial application. The thermodynamic plateau pressure of LaNi5 material is relatively high and exhibits significant hysteresis, with an equilibrium hydrogen pressure of approximately 2-3 atmospheres at room temperature. While this is beneficial for hydrogen release at room temperature, it requires additional pressurization equipment for hydrogen absorption at lower pressures (such as the pressure of hydrogen production through water electrolysis), increasing system complexity and energy consumption. Simultaneously, the pressure hysteresis between its hydrogen absorption and release plateaus reduces thermodynamic efficiency. Furthermore, its cycle stability is insufficient, and it is prone to pulverization. During hydrogen absorption and release, the cell volume undergoes approximately 23% expansion and contraction. This repeated and drastic volume change generates enormous internal stress, causing the alloy particles to continuously break and pulverize. Pulverization not only reduces the alloy's macroscopic thermal conductivity and hydrogen diffusion rate, deteriorating kinetic performance, but the fine powder can also clog system pipelines and accelerate surface oxidation poisoning due to increased specific surface area, ultimately leading to a rapid decline in the alloy's effective capacity and a shortened cycle life. The main elements in LaNi5 alloy, La and Ni, are both relatively expensive metals. Especially in recent years, with the development of new energy vehicles and the electronics industry, nickel prices have fluctuated significantly. How to reduce the raw material costs of the alloy without significantly sacrificing performance is an economic issue that must be considered for large-scale application.

[0004] To improve the performance of LaNi5, existing technologies typically employ partial element substitution. For example, partially substituting La with rare earth elements such as Ce and Nd can adjust the cell volume and thermodynamic parameters, improving kinetics and resistance to pulverization. Partially substituting Ni with transition metals such as Fe, Mn, Al, and Co can effectively reduce plateau pressure, improve cycle stability, and control costs. However, single element substitution often only improves one aspect of performance and may have side effects (e.g., excessive Fe or Mn substitution can reduce capacity). Summary of the Invention

[0005] The purpose of this invention is to provide an easily activated AB5-type multi-component doped modified hydrogen storage material, its preparation method and application, which, while maintaining high hydrogen storage capacity, has adjustable hydrogen absorption / desorption plateau pressure, faster hydrogen absorption / desorption kinetics and significantly improved activation performance.

[0006] The objective of this invention can be achieved through the following technical solutions: In a first aspect, the present invention provides an easily activated AB5-type multi-component doped modified hydrogen storage material, the chemical formula of which is: La x Ce y Nd z Ni a Fe b Mn c Where x+y+z=1, x≥0.5, 0≤y≤0.5, 0≤z≤0.5; a+b+c=5, a≥4, 0≤b≤1, 0≤c≤1, and at least two of y, z, b, and c are not equal to 0.

[0007] Furthermore, 0.8≤x≤1, for example, x can be 0.8, 0.85, 0.9, 0.95, or 1; 0≤y≤0.1, for example, y can be 0, 0.02, 0.04, 0.06, 0.08, or 0.1; 0≤z≤0.1, for example, z can be 0, 0.02, 0.04, 0.06, 0.08, or 0.1.

[0008] Furthermore, 4≤a≤5, for example, a can be 4, 4.5, or 5; 0≤b≤0.5, for example, b can be 0, 0.1, 0.2, 0.3, 0.4, or 0.5; 0≤c≤0.5, for example, c can be 0, 0.1, 0.2, 0.3, 0.4, or 0.5.

[0009] Furthermore, the hydrogen storage material has a hexagonal single phase and a mass hydrogen storage density > 1.35 wt%.

[0010] In a second aspect, the present invention provides a method for preparing an easily activated AB5-type multi-component doped modified hydrogen storage material, comprising the following steps: S1. Select elemental metals of La, Ce, Nd, Ni, Fe, and Mn with a purity ≥ 99.9%. Place the pretreated raw materials into the crucible of a medium-frequency induction melting furnace, evacuate, and introduce argon gas as a protective gas for melting. After the alloy is completely melted and the liquid metal is observed to be boiling, refine it. S2, pouring into a copper mold to obtain La x Ce y Nd z Ni a Fe b Mn c The alloy ingot was crushed to obtain AB5-type multi-doped modified hydrogen storage material.

[0011] Furthermore, the smelting power is 20 kW, and the time is 2~20 min.

[0012] Furthermore, the refining power is 18 kW, and the time is 2-4 minutes.

[0013] Furthermore, the pressure during the smelting and refining process is 0.04~0.06 MPa.

[0014] Furthermore, the particles are crushed to a target particle size of 100-400 mesh.

[0015] In a third aspect, the present invention provides the application of easily activated AB5-type multi-doped modified hydrogen storage materials in hydrogen energy storage, hydrogen compression, or battery anode materials.

[0016] Compared with the prior art, the present invention has the following advantages: (1) The alloy provided by the present invention can absorb hydrogen without hydrogen absorption or desorption activation; (2) The AB5 hydrogen storage alloy provided by the present invention has significantly improved hydrogen absorption and desorption hysteresis compared with the traditional LaNi5 alloy; (3) Compared with technologies such as electric arc melting furnaces, the induction melting technology used in this invention can achieve kilogram-level (or even hundred-kilogram-level) preparation.

[0017] (4) The AB5 hydrogen storage alloy of the present invention has a high hydrogen storage capacity (>1.38 wt.%) and a fast hydrogen absorption and desorption rate, and can quickly reach the saturation hydrogen absorption capacity; (5) The AB5 type hydrogen storage alloy provided by this invention has excellent hydrogen storage performance and has broad development prospects in the field of new energy. Attached Figure Description

[0018] Figure 1 LaNi5 and La prepared for Comparative Example 1 and Examples 1-3 0.8 Ce 0.1 Nd 0.1Ni5, LaNi4Fe 0.5 Mn 0.5 La 0.8 Ce 0.1 Nd 0.1 Ni4Fe 0.5 Mn 0.5 XRD pattern of the as-cast alloy; Figure 2 SEM and EDS images of the LaNi5 as-cast alloy prepared in Comparative Example 1; Figure 3 Hydrogen absorption kinetics curves of the LaNi5 as-cast alloy prepared for Comparative Example 1 at 30℃, 50℃, 70℃ and 3 MPa. Figure 4 PCT curves of the LaNi5 as-cast alloy prepared for Comparative Example 1 at 30℃, 50℃, 70℃ and 3 MPa. Figure 5 La prepared in Example 1 0.8 Ce 0.1 Nd 0.1 SEM and EDS images of Ni5 as-cast alloy; Figure 6 La prepared in Example 1 0.8 Ce 0.1 Nd 0.1 Hydrogen absorption kinetics curves of Ni5 as-cast alloy at 30℃, 50℃, 70℃ and 3 MPa; Figure 7 La prepared in Example 1 0.8 Ce 0.1 Nd 0.1 PCT curves of Ni5 as-cast alloy at 30℃, 50℃, 70℃ and 3 MPa. Figure 8 LaNi4Fe prepared in Example 2 0.5 Mn 0.5 SEM and EDS images of the as-cast alloy; Figure 9 LaNi4Fe prepared in Example 2 0.5 Mn 0.5 Hydrogen absorption kinetics curves of the as-cast alloy at 30℃, 50℃, 70℃ and 3 MPa; Figure 10 LaNi4Fe prepared in Example 2 0.5 Mn 0.5 PCT curves of as-cast alloys at 30℃, 50℃, 70℃, and 3 MPa; Figure 11 La prepared in Example 3 0.8 Ce 0.1 Nd0.1 Ni4Fe 0.5 Mn 0.5 SEM and EDS images of the as-cast alloy; Figure 12 La prepared in Example 3 0.8 Ce 0.1 Nd 0.1 Ni4Fe 0.5 Mn 0.5 Hydrogen absorption kinetics curves of the as-cast alloy at 30℃, 50℃, 70℃ and 3MPa; Figure 13 La prepared in Example 3 0.8 Ce 0.1 Nd 0.1 Ni4Fe 0.5 Mn 0.5 PCT curves of as-cast alloys at 30℃, 50℃, 70℃, and 3MPa; Figure 14 LaNi5 and La prepared for Comparative Example 1 and Examples 1-3 0.8 Ce 0.1 Nd 0.1 Ni5, LaNi4Fe 0.5 Mn 0.5 La 0.8 Ce 0.1 Nd 0.1 Ni4Fe 0.5 Mn 0.5 Hydrogen absorption kinetics curve of the as-cast alloy at 50℃ and 3 MPa; Figure 15 LaNi5 and La prepared for Comparative Example 1 and Examples 1-3 0.8 Ce 0.1 Nd 0.1 Ni5, LaNi4Fe 0.5 Mn 0.5 La 0.8 Ce 0.1 Nd 0.1 Ni4Fe 0.5 Mn 0.5 PCT curve of the as-cast alloy at 50℃ and 3 MPa.

[0019] Figure 16 LaNi5 and La prepared for Comparative Example 1 and Examples 1-3 0.8 Ce 0.1 Nd 0.1 Ni5, LaNi4Fe 0.5 Mn 0.5 La 0.8 Ce 0.1 Nd 0.1Ni4Fe 0.5 Mn 0.5 The initial hydrogen absorption kinetics curve of the as-cast alloy at 100℃ and 3 MPa. Detailed Implementation

[0020] The present invention will now be described in detail with reference to the accompanying drawings and specific embodiments. These embodiments are based on the technical solution of the present invention and provide detailed implementation methods and specific operating procedures. However, the scope of protection of the present invention is not limited to the following embodiments.

[0021] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application belongs. The terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of this application.

[0022] As used herein, the terms "and / or," "or / and," and "and / or" encompass any one of two or more of the related listed items, as well as any and all combinations of the related listed items. These arbitrary and all combinations include any two related listed items, any more related listed items, or a combination of all related listed items. It should be noted that when at least three items are connected using at least two conjunctions selected from "and / or," "or / and," and "and / or," it should be understood that, in this application, the technical solution undoubtedly includes solutions connected by "logical AND," and also undoubtedly includes solutions connected by "logical OR."

[0023] In this application, the technical features described in an open-ended manner include both closed technical solutions consisting of the listed features and open technical solutions that include the listed features.

[0024] In this application, numerical ranges are referred to as continuous unless otherwise specified, and include the minimum and maximum values ​​of the range, as well as every value between the minimum and maximum values. Furthermore, when the range refers to integers, it includes every integer between the minimum and maximum values ​​of the range. Additionally, when multiple ranges are provided to describe a feature or characteristic, the ranges may be merged. In other words, unless otherwise specified, all ranges disclosed herein should be understood to include any and all subranges to which they are incorporated.

[0025] This document only specifically discloses some numerical ranges. However, any lower limit can be combined with any upper limit to form an unspecified range; and any lower limit can be combined with other lower limits to form an unspecified range, just as any upper limit can be combined with any other upper limit to form an unspecified range. Furthermore, each individually disclosed point or single value can itself serve as a lower or upper limit and be combined with any other point or single value or with other lower or upper limits to form an unspecified range.

[0026] Unless otherwise specified, the temperature parameters in this application may be either constant temperature processing or processing within a certain temperature range. The constant temperature processing allows temperature fluctuations within the precision range controlled by the instrument, such as ±5°C, ±4°C, ±3°C, ±2°C, or ±1°C.

[0027] In this document, the term "suitable" as used in phrases such as "suitable combination," "suitable method," and "any suitable method" refers to the ability to implement the technical solution of this application, solve the technical problem of this application, and achieve the expected technical effect of this application.

[0028] In this application, terms such as "further," "even further," and "particularly" are used to describe purposes and indicate differences in content, but should not be construed as limiting the scope of protection of this application.

[0029] In this application, "optionally," "optionally," and "optional" mean that something is optional, that is, it means that it is selected from either "with" or "without." If there are multiple "optional" entries in a technical solution, unless otherwise specified and there are no contradictions or mutual constraints, each "optional" entry shall be independent.

[0030] In the description of the application, "multiple" means at least two, such as two, three, etc., unless otherwise explicitly specified.

[0031] Unless otherwise specified, all preparations and tests described herein took place at 25°C.

[0032] The terms “comprising,” “including,” “containing,” “having,” “comprising,” or other variations thereof are intended to cover non-closed inclusion, and no distinction is made between these terms. The term “comprising” means that other steps and ingredients may be added without affecting the final result. The compositions and methods / processes of the present invention comprise, consist of, and substantially consist of the essential elements and limitations described herein, as well as any additional or optional ingredients, components, steps, or limitations described herein. No distinction is made between the terms “efficacy,” “performance,” “effect,” and “potency” herein.

[0033] Unless otherwise specified, all embodiments and optional embodiments of this application can be combined to form new technical solutions. Unless otherwise specified, all technical features and optional technical features of this application can be combined to form new technical solutions.

[0034] Unless otherwise specified, all steps in this application may be performed sequentially or randomly, but sequentially is preferred.

[0035] Comparative Example 1 An AB5 type hydrogen storage alloy, with the composition LaNi5, is prepared according to the following method: Step 1: Design the composition LaNi5, convert the atomic percentage of each component into mass percentage, and ensure that the purity of elemental La and Ni is above 99.9%; Step 2: Place the raw materials in a beaker containing alcohol for ultrasonic cleaning to remove the oxide layer on the surface of the materials. After ultrasonic cleaning, place them in a drying oven to dry. The batching is based on the mass of the alloy ingot and the mass percentage of the alloy composition for each smelting, and a certain amount of La burn-off rate (3 wt.%) is taken into account. Step 3: Add the processed raw materials to the crucible of the induction melting furnace, arranging them in order of decreasing melting point from bottom to top. Before starting melting, evacuate the arc melting furnace to a vacuum level of 1×10⁻⁶. -3 Below Pa; Argon gas is introduced into the cavity to 0.05 MPa as a protective gas during the smelting process.

[0036] Step 4: Turn on the power of the induction melting furnace and uniformly increase the power to 20 kW within 15 minutes. Maintain this power for 3 minutes until the alloy is completely melted and the liquid metal is observed to be boiling. Then reduce the power to 18 kW and refine for 3 minutes. Subsequently, pour the alloy into a copper mold, remove the alloy ingot, and crush it to the target particle size (e.g., 200 mesh) for testing.

[0037] Figure 1 XRD patterns and Figure 2 SEM and EDS spectra show that a single-phase LaNi5 hydrogen storage alloy with hexagonal crystal structure was successfully prepared, with moderate particle size and uniform element distribution.

[0038] Hydrogen storage performance of AB5 alloy: The LaNi5 alloy was activated by undergoing two hydrogen absorption and desorption cycles at 100℃, and then its hydrogen storage performance was tested.

[0039] Figure 3The hydrogen absorption and desorption kinetics of LaNi5 hydrogen storage alloy at temperatures of 303 K / 323 K / 353 K and a hydrogen pressure of 3 MPa are shown. Figure 3 It can be seen that the hydrogen absorption rate of the LaNi5 alloy gradually decreases with increasing temperature, while the hydrogen desorption rate gradually increases with increasing temperature. Within the tested temperature range, the LaNi5 hydrogen storage alloy maintains a relatively fast hydrogen absorption and desorption rate. Taking 323K as an example, the LaNi5 hydrogen storage alloy completes saturated hydrogen absorption and complete hydrogen desorption in 100 s and 360 s, respectively, with a maximum hydrogen absorption capacity of 1.55 wt.%.

[0040] Figure 4 The thermodynamic curves of hydrogen absorption and desorption of LaNi5 hydrogen storage alloy at temperatures of 303 K / 323 K / 353 K and a hydrogen pressure of 3 MPa are shown. Figure 4 It can be seen that the hydrogen absorption / desorption plateau pressure of the LaNi5 alloy gradually increases with increasing temperature. Within the tested temperature range, the LaNi5 hydrogen storage alloy exhibits good hydrogen storage performance. Taking 323 K as an example, the maximum hydrogen storage capacity of the LaNi5 hydrogen storage alloy is 1.56 wt.%, which is basically consistent with the hydrogen absorption / desorption kinetics test data.

[0041] Example 1 An AB5 type hydrogen storage alloy with the composition La 0.8 Ce 0.1 Nd 0.1 Ni5 was prepared according to the following preparation method: Step 1: Design component La 0.8 Ce 0.1 Nd 0.1 Ni5, when the atomic percentages of each component are converted to mass percentages, shows that the purity of elemental La, Ce, Nd and Ni is all above 99.9%; Step 2: Place the raw materials in a beaker containing alcohol for ultrasonic cleaning to remove the oxide layer on the surface of the materials. After ultrasonic cleaning, place them in a drying oven to dry. The batching is based on the mass of the alloy ingot and the mass percentage of the alloy composition for each smelting, taking into account a certain amount of La, Ce and Nd burn-off rate (3 wt.%). Step 3: Add the processed raw materials to the crucible of the induction melting furnace, arranging them in order of decreasing melting point from bottom to top. Before starting melting, evacuate the arc melting furnace to a vacuum level of 1×10⁻⁶. -3 Below Pa; Argon gas is introduced into the cavity to 0.05 MPa as a protective gas during the smelting process.

[0042] Step 4: Turn on the power of the induction melting furnace and uniformly increase the power to 20 kW within 15 minutes. Maintain this power for 3 minutes until the alloy is completely melted and the liquid metal is observed to be boiling. Then reduce the power to 18 kW and refine for 3 minutes. Subsequently, pour the alloy into a copper mold, remove the alloy ingot, and crush it to the target particle size (200 mesh) for testing.

[0043] Figure 1 XRD patterns and Figure 5 SEM and EDS spectra indicate that a single-phase La with a hexagonal crystal structure was successfully prepared. 0.8 Ce 0.1 Nd 0.1 Ni5 hydrogen storage alloy has a moderate particle size and uniform element distribution.

[0044] La 0.8 Ce 0.1 Nd 0.1 Hydrogen storage performance of Ni5 alloy: La 0.8 Ce 0.1 Nd 0.1 The Ni5 alloy was vacuum-pumped at 100°C for 1 hour to complete the La process. 0.8 Ce 0.1 Nd 0.1 The Ni5 hydrogen storage alloy was activated, and then its hydrogen storage performance was tested.

[0045] Figure 6 La was shown 0.8 Ce 0.1 Nd 0.1 Hydrogen absorption and desorption kinetics of Ni5 hydrogen storage alloy at temperatures of 303 K / 323 K / 353 K and a hydrogen pressure of 3 MPa were tested. (Source: [Insert source here]) Figure 6 It can be seen that La 0.8 Ce 0.1 Nd 0.1 The hydrogen absorption rate of Ni5 alloy gradually decreases with increasing temperature, while the hydrogen release rate gradually increases with increasing temperature. Within the tested temperature range, La... 0.8 Ce 0.1 Nd 0.1 Ni5 hydrogen storage alloys maintain relatively fast hydrogen absorption and desorption rates. Taking 323 K as an example, La... 0.8 Ce 0.1 Nd 0.1 The Ni5 hydrogen storage alloy achieved saturated hydrogen absorption and complete hydrogen dehydrogenation at 260 s and 400 s, respectively, with a maximum hydrogen absorption capacity of 1.44 wt.%.

[0046] Figure 7 La was shown 0.8 Ce 0.1 Nd 0.1Thermodynamic test curves of hydrogen absorption and desorption of Ni5 hydrogen storage alloy at temperatures of 303 K / 323 K / 353 K and hydrogen pressure of 3 MPa. (Source: [Insert source here]) Figure 7 It can be seen that La 0.8 Ce 0.1 Nd 0.1 The hydrogen absorption / desorption plateau pressure of Ni5 alloy gradually increases with increasing temperature. Within the tested temperature range, La... 0.8 Ce 0.1 Nd 0.1 Ni5 hydrogen storage alloys exhibit excellent hydrogen storage performance. Taking 323 K as an example, La... 0.8 Ce 0.1 Nd 0.1 The maximum hydrogen storage capacity of Ni5 hydrogen storage alloy is 1.54 wt.%, which is basically consistent with the hydrogen absorption and desorption kinetics test data.

[0047] Example 2 An AB5 type hydrogen storage alloy with the composition LaNi4Fe 0.5 Mn 0.5 The above alloy was prepared according to the following preparation method: Step 1: Designing the composition LaNi4Fe 0.5 Mn 0.5 The atomic percentages of each component were converted into mass percentages, and the purity of elemental La, Fe, Mn and Ni was all above 99.9%. Step 2: Place the raw materials into a beaker containing alcohol for ultrasonic cleaning to remove the oxide layer on the surface of the materials. After ultrasonic cleaning, place them in a drying oven to dry. The batching is based on the mass of the alloy ingot and the mass percentage of the alloy composition for each smelting, taking into account a certain amount of La and Mn burn-off rate (3 wt.%). Step 3: Add the processed raw materials to the crucible of the induction melting furnace, arranging them in order of decreasing melting point from bottom to top. Before starting melting, evacuate the arc melting furnace to a vacuum level of 1×10⁻⁶. -3 Below Pa; Argon gas is introduced into the cavity to 0.05 MPa as a protective gas during the smelting process.

[0048] Step 4: Turn on the power of the induction melting furnace and uniformly increase the power to 20 kW within 15 minutes. Maintain this power for 3 minutes until the alloy is completely melted and the liquid metal is observed to be boiling. Then reduce the power to 18 kW and refine for 3 minutes. Subsequently, pour the alloy into a copper mold, remove the alloy ingot, and crush it to the target particle size (200 mesh) for testing.

[0049] Figure 1 XRD patterns and Figure 8SEM and EDS spectra indicate that a single-phase LaNi4Fe with a hexagonal crystal structure was successfully prepared. 0.5 Mn 0.5 Hydrogen storage alloy with moderate particle size and uniform element distribution.

[0050] LaNi4Fe 0.5 Mn 0.5 Alloy hydrogen storage performance: LaNi4Fe 0.5 Mn 0.5 The alloy was vacuum-sealed at 100°C for 1 hour to complete the LaNi4Fe alloy. 0.5 Mn 0.5 The hydrogen storage alloy is activated, and then its hydrogen storage performance is tested.

[0051] Figure 9 LaNi4Fe was shown 0.5 Mn 0.5 Hydrogen absorption and desorption kinetics of the hydrogen storage alloy at temperatures of 303 K / 323 K / 353 K and a hydrogen pressure of 3 MPa were tested. (Source: [Insert Source Here]) Figure 9 It can be seen that LaNi4Fe 0.5 Mn 0.5 The hydrogen absorption rate of the alloy gradually decreases with increasing temperature, while the hydrogen release rate gradually increases with increasing temperature. Within the tested temperature range, LaNi4Fe... 0.5 Mn 0.5 Hydrogen storage alloys maintain relatively fast hydrogen absorption and desorption rates. Taking 323 K as an example, LaNi4Fe... 0.5 Mn 0.5 The hydrogen storage alloy achieved saturated hydrogen absorption and complete hydrogen dehydrogenation at 75 s and 300 s, respectively, with a maximum hydrogen absorption capacity of 1.39 wt.%.

[0052] Figure 10 La was shown 0.8 Ce 0.1 Nd 0.1 Thermodynamic test curves of hydrogen absorption and desorption of Ni5 hydrogen storage alloy at temperatures of 303 K / 323 K / 353 K and hydrogen pressure of 3 MPa. (Source: [Insert source here]) Figure 10 It can be seen that LaNi4Fe 0.5 Mn 0.5 The hydrogen absorption / desorption plateau pressure of the alloy gradually increases with increasing temperature. Within the tested temperature range, LaNi4Fe 0.5 Mn 0.5 Hydrogen storage alloys exhibit excellent hydrogen storage performance. Taking 323 K as an example, La... 0.8 Ce 0.1 Nd 0.1 The maximum hydrogen storage capacity of Ni5 hydrogen storage alloy is 1.40 wt.%, which is basically consistent with the hydrogen absorption and desorption kinetics test data.

[0053] Example 3 An AB5 type hydrogen storage alloy with the composition La 0.8 Ce 0.1 Nd 0.1 Ni4Fe 0.5 Mn 0.5 The above alloy was prepared according to the following preparation method: Step 1: Design component La 0.8 Ce 0.1 Nd 0.1 Ni4Fe 0.5 Mn 0.5 The atomic percentages of each component were converted into mass percentages, and the purity of the elemental La, Ce, Nd, Fe, Mn and Ni was all above 99.9%. Step 2: Place the raw materials in a beaker containing alcohol for ultrasonic cleaning to remove the oxide layer on the surface of the materials. After ultrasonic cleaning, place them in a drying oven to dry. The batching is based on the mass of the alloy ingot and the mass percentage of the alloy composition for each smelting, and a certain amount of La, Ce, Nd and Mn burn-off rate (3 wt.%) is taken into account. Step 3: Add the processed raw materials to the crucible of the induction melting furnace, arranging them in order of decreasing melting point from bottom to top. Before starting melting, evacuate the arc melting furnace to a vacuum level of 1×10⁻⁶. -3 Below Pa; Argon gas is introduced into the cavity to 0.05 MPa as a protective gas during the smelting process.

[0054] Step 4: Turn on the power of the induction melting furnace and uniformly increase the power to 20 kW within 15 minutes. Maintain this power for 3 minutes until the alloy is completely melted and the liquid metal is observed to be boiling. Then reduce the power to 18 kW and refine for 3 minutes. Subsequently, pour the alloy into a copper mold, remove the alloy ingot, and crush it to the target particle size (e.g., 100-400 mesh) for testing.

[0055] Figure 1 XRD patterns and Figure 11 SEM and EDS spectra indicate that a single-phase La with a hexagonal crystal structure was successfully prepared. 0.8 Ce 0.1 Nd 0.1 Ni4Fe 0.5 Mn 0.5 Hydrogen storage alloy with moderate particle size and uniform element distribution.

[0056] La 0.8 Ce 0.1 Nd 0.1 Ni4Fe 0.5 Mn0.5 Alloy hydrogen storage performance: La 0.8 Ce 0.1 Nd 0.1 Ni4Fe 0.5 Mn 0. The alloy was vacuum-sealed at 100°C for 1 hour to complete the La process. 0.8 Ce 0.1 Nd 0.1 Ni4Fe 0.5 Mn 0.5 The hydrogen storage alloy is activated, and then its hydrogen storage performance is tested.

[0057] Figure 12 La was shown 0.8 Ce 0.1 Nd 0.1 Ni4Fe 0.5 Mn 0.5 Hydrogen absorption and desorption kinetics of the hydrogen storage alloy at temperatures of 303 K / 323 K / 353 K and a hydrogen pressure of 3 MPa were tested. (Source: [Insert Source Here]) Figure 12 It can be seen that La 0.8 Ce 0.1 Nd 0.1 Ni4Fe 0.5 Mn 0.5 The hydrogen absorption rate of the alloy gradually decreases with increasing temperature, while the hydrogen release rate gradually increases with increasing temperature. Within the tested temperature range, La... 0.8 Ce 0.1 Nd 0.1 Ni4Fe 0.5 Mn 0.5 Hydrogen storage alloys maintain relatively fast hydrogen absorption and desorption rates. Taking 323 K as an example, La... 0.8 Ce 0.1 Nd 0.1 Ni4Fe 0.5 Mn 0.5 The hydrogen storage alloy achieved saturated hydrogen absorption and complete hydrogen dehydrogenation in 80 s and 310 s, respectively, with a maximum hydrogen absorption capacity of 1.38 wt.%.

[0058] Figure 13 La was shown 0.8 Ce 0.1 Nd 0.1 Ni4Fe 0.5 Mn 0.5 Thermodynamic curves of hydrogen absorption and desorption of the hydrogen storage alloy at temperatures of 303 K / 323 K / 353 K and a hydrogen pressure of 3 MPa. (Source: [Insert source here]) Figure 13 It can be seen that La 0.8 Ce 0.1 Nd 0.1 Ni4Fe 0.5Mn 0.5 The hydrogen absorption / desorption plateau pressure of the alloy gradually increases with increasing temperature. Within the tested temperature range, La... 0.8 Ce 0.1 Nd 0.1 Ni4Fe 0.5 Mn 0.5 Hydrogen storage alloys exhibit excellent hydrogen storage performance. Taking 323 K as an example, La... 0.8 Ce 0.1 Nd 0.1 Ni4Fe 0.5 Mn 0.5 The maximum hydrogen storage capacity of the hydrogen storage alloy is 1.39 wt.%, which is basically consistent with the hydrogen absorption and desorption kinetics test data.

[0059] The LaNi5 and La prepared in Comparative Example 1 and Examples 1 to 3 above 0.8 Ce 0.1 Nd 0.1 Ni5, LaNi4Fe 0.5 Mn 0.5 La 0.8 Ce 0.1 Nd 0.1 Ni4Fe 0.5 Mn 0.5 Activation performance testing of as-cast alloys, such as... Figure 16 As shown, the graph displays the initial hydrogen absorption kinetics curves at 100℃ and 3 MPa. It can be seen that the initial saturation hydrogen absorption times for the four materials are approximately 200 s, 60 s, 80 s, and 80 s, respectively. This indicates that the activation performance of each embodiment is significantly better than that of Comparative Example 1, demonstrating that the hydrogen storage material obtained by modifying the traditional LaNi5 alloy with multiple doping methods in this invention achieves a significant improvement in activation performance while maintaining a high hydrogen storage capacity.

[0060] In summary, compared to the traditional LaNi5 alloy, the multi-component doping modification in Examples 1-3 resulted in a slight decrease in the maximum hydrogen absorption capacity, but still maintained a high hydrogen storage capacity of >1.38 wt.%. Furthermore, the activation performance of the hydrogen storage alloys obtained in each example was significantly improved after doping, enabling rapid hydrogen absorption on the first attempt. In contrast, Comparative Example 1 exhibited a slower initial hydrogen absorption rate, requiring multiple activations to improve the absorption rate. Additionally, further integration... Figure 15 The PCT curves reflect the hydrogen absorption and desorption hysteresis of the hydrogen storage alloy. It can be seen from the phenomenon that the hydrogen absorption equilibrium pressure (Pa) is higher than the hydrogen desorption equilibrium pressure (Pd) under the same hydrogen content. In particular, Examples 2 and 3, which modify the B site, show a significant improvement in hysteresis.

[0061] The above description of the embodiments is provided to enable those skilled in the art to understand and use the invention. It will be apparent to those skilled in the art that various modifications can be made to these embodiments, and the general principles described herein can be applied to other embodiments without inventive effort. Therefore, the present invention is not limited to the above embodiments, and any improvements and modifications made by those skilled in the art based on the disclosure of the present invention without departing from the scope of the invention should be within the protection scope of the present invention.

Claims

1. An easily activated AB5-type multi-component doped modified hydrogen storage material, characterized in that, Its general chemical formula is: La x Ce y Nd z Ni a Fe b Mn c Where x+y+z=1, x≥0.5, 0≤y≤0.5, 0≤z≤0.5; a+b+c=5, a≥4, 0≤b≤1, 0≤c≤1, and at least two of y, z, b, and c are not equal to 0.

2. The easily activated AB5-type multi-component doped modified hydrogen storage material according to claim 1, characterized in that, 0.8≤x≤1, 0≤y≤0.1, 0≤z≤0.

1.

3. The easily activated AB5-type multi-component doped modified hydrogen storage material according to claim 1, characterized in that, 4≤a≤5, 0≤b≤0.5, 0≤c≤0.

5.

4. The easily activated AB5-type multi-component doped modified hydrogen storage material according to claim 1, characterized in that, It has a hexagonal single phase and a mass hydrogen storage density >1.35wt%.

5. The method for preparing the easily activated AB5-type multi-component doped modified hydrogen storage material according to any one of claims 1-4, characterized in that, Includes the following steps: S1. Select elemental metals of La, Ce, Nd, Ni, Fe, and Mn with a purity ≥ 99.9%. Place the pretreated raw materials into the crucible of a medium-frequency induction melting furnace, evacuate, and introduce argon gas as a protective gas for melting. After the alloy is completely melted and the liquid metal is observed to be boiling, refine it. S2, pouring into a copper mold to obtain La x Ce y Nd z Ni a Fe b Mn c The alloy ingot was crushed to obtain AB5-type multi-doped modified hydrogen storage material.

6. The method for preparing the easily activated AB5-type multi-component doped modified hydrogen storage material according to claim 5, characterized in that, The smelting power is 20 kW, and the time is 2~20 min.

7. The method for preparing the easily activated AB5-type multi-component doped modified hydrogen storage material according to claim 5, characterized in that, The refining process has a power of 18 kW and a time of 2-4 minutes.

8. The method for preparing the easily activated AB5-type multi-component doped modified hydrogen storage material according to claim 5, characterized in that, The pressure during the smelting and refining process is 0.04~0.06 MPa.

9. The method for preparing the easily activated AB5-type multi-component doped modified hydrogen storage material according to claim 5, characterized in that, Crushed to the target particle size of 100~400 mesh.

10. The application of the easily activated AB5-type multi-component doped modified hydrogen storage material as described in any one of claims 1-4 in hydrogen energy storage, hydrogen compression, or battery anode materials.

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