Ti-V-based hydrogen storage alloy and preparation method thereof

Abstract

The invention relates to the technical field of hydrogen storage materials, in particular to a Ti-V-based hydrogen storage alloy and a preparation method thereof.The general formula of the Ti-V-based hydrogen storage alloy is Ti1-x-y-zMoxVyMz, x is larger than or equal to 0.002 and smaller than or equal to 0.1, y is larger than or equal to 0.4 and smaller than or equal to 0.6, z is larger than or equal to 0.05 and smaller than or equal to 0.3, and M is at least one of cobalt, chromium, iron, manganese and nickel. And the multi-principal-element alloy with ultra-refined grains is formed. By means of component design and improvement of the preparation method, the technical effects of improving the hydrogen dynamic performance, weakening the hysteresis effect and improving the hydrogen absorption and desorption cycle index and stability are achieved.

Description

Technical Field

[0001] The invention relates to the technical field of hydrogen storage materials, and in particular to a Ti-V based hydrogen storage alloy and a preparation method thereof. Background Art

[0002] With the advancement of science and technology and the development of society, human demand for energy is growing. However, traditional fossil energy is becoming increasingly depleted, and the environmental problems it causes are becoming increasingly serious. Hydrogen energy, as a truly "zero-emission" clean energy, can be obtained by making water, which is easy to obtain; the combustion product is water, which can be directly discharged into the atmosphere without causing pollution, and it can be used in fuel cells.

[0003] Since hydrogen is easy to gasify, burn and explode, the storage and transportation of hydrogen is the most difficult and critical link in the application of hydrogen energy. At present, the main means of hydrogen storage include gaseous hydrogen storage, liquid hydrogen storage and solid hydrogen storage. Gaseous hydrogen storage and liquid hydrogen storage are dangerous, have low hydrogen storage density and are easy to leak, making them difficult to promote to a wide range of applications; solid hydrogen storage, especially chemical adsorption solid hydrogen storage, stores hydrogen through the chemical reaction of hydrogen and hydrogen storage alloy powder, which is safe, has high volume hydrogen storage density and is leak-free, and has a very broad application prospect.

[0004] For solid-state hydrogen storage materials, there are currently two main systems: magnesium-based alloy materials and titanium-based alloy materials. Titanium-based hydrogen storage materials are abundant in resources, low in cost, high in mass hydrogen storage density, and low in hydrogen release temperature. Hydrogen can be released at room temperature, making them safer and more widely used. However, they are still difficult to activate, and hydrogen absorption and desorption need to be carried out at higher temperatures and pressures. They are also susceptible to CO and O 2 It has the disadvantages of being poisoned by gas impurities, severe hysteresis, short cycle life, and performance degradation after repeated hydrogen absorption.

[0005] Ti-V based hydrogen storage alloys have good hydrogen storage performance and hydrogen absorption and desorption kinetics at room temperature and normal pressure. The theoretical hydrogen storage capacity can reach 3.8%. It has the advantages of large reversible hydrogen storage capacity and fast hydrogen diffusion rate in hydrides. It can be better used in scenarios such as hydrogen supply for urban transport vehicles and hydrogen power supply.

[0006] At the same time, regarding the preparation methods, the commonly used preparation methods include vacuum induction melting, quenching treatment, etc., which achieve the purpose of improving performance by changing the microstructure of the alloy, but the improvement effect is not good; while the additive manufacturing process can weaken element segregation and refine the grains, thereby further improving the hydrogen storage performance of the alloy, and has broad application prospects. Summary of the invention

[0007] The purpose of the present invention is to provide a Ti-V based hydrogen storage alloy and a preparation method thereof, wherein the alloy has the characteristics of high effective hydrogen storage capacity, fast hydrogen release rate, good hydrogen storage performance and hydrogen absorption and desorption kinetics performance; the present invention also provides a preparation method of the Ti-V based hydrogen storage alloy, by changing the alloy phase structure and organizational uniformity, so that the alloy material has higher activation performance while ensuring the hydrogen storage capacity, and the hysteresis effect of hydrogen absorption and desorption is greatly reduced; the number of hydrogen absorption and desorption cycles and stability are greatly improved.

[0008] To achieve the above object, the embodiments of the present invention adopt the following technical solutions:

[0009] In one aspect, the present invention provides a Ti-V based hydrogen storage alloy, wherein the general formula of the Ti-V based hydrogen storage alloy is: Ti 1-x-y-z Mo x V y M z , wherein 0.002≤x≤0.1, 0.4≤y≤0.6, 0.05≤z≤0.3, and M is at least one of cobalt, chromium, iron, manganese and nickel.

[0010] In some embodiments, the purity of the raw material of the Ti-V based hydrogen storage alloy is ≥ 99.9%.

[0011] In another aspect, the present invention provides a method for preparing a Ti-V based hydrogen storage alloy, comprising the following steps:

[0012] The Ti-V based hydrogen storage alloy is prepared by mixing the metal raw materials according to their contents, preparing spherical powder by a gas atomization method, and then 3D printing, heat treatment and crushing are performed by laser melting deposition equipment to obtain the Ti-V based hydrogen storage alloy.

[0013] In some embodiments, the parameters of the laser melting deposition 3D printing are laser power 800-1000W, scanning speed 600-800mm / min, scanning spacing 1-2mm, and layer height 0.2-0.4mm.

[0014] In some embodiments, the spherical powder has a particle size of 15 to 150 μm.

[0015] In some embodiments, the specific conditions of the heat treatment are: 400-600° C. insulation for 3-6 hours for stress relief annealing.

[0016] In some embodiments, the specific process of crushing is first crushing and passing through a 200-mesh sieve, and then ball milling under the protection of inert gas. The ball milling conditions are a ball-to-material ratio of 40:1, a rotation speed of 350 rpm, and a 1-hour shutdown for every 2 hours of ball milling.

[0017] In some embodiments, the titanium element is derived from raw material sponge titanium, and the purity of the raw material is not less than 99.9%.

[0018] In some embodiments, the molybdenum element is derived from raw molybdenum particles, and the purity of the raw material is not less than 99.9%.

[0019] In some embodiments, the vanadium element is derived from raw material dendrite vanadium, and the purity of the raw material is not less than 99.9%.

[0020] In some embodiments, the cobalt element is derived from raw electrolytic cobalt, and the purity of the raw material is not less than 99.9%.

[0021] In some embodiments, the chromium element is derived from raw chromium particles, and the purity of the raw material is not less than 99.9%.

[0022] In some embodiments, the iron element comes from raw iron blocks, and the purity of the raw iron blocks is not less than 99.9%.

[0023] In some embodiments, the manganese element is derived from raw material electrolytic manganese, and the purity of the raw material is not less than 99.9%.

[0024] In some embodiments, the nickel element is derived from raw material electrolytic nickel, and the purity of the raw material is not less than 99.9%.

[0025] Compared with the prior art, the present invention has at least the following beneficial effects:

[0026] 1. In terms of composition design, in the Ti-V series hydrogen storage alloy, Mo is used to partially replace Ti, and the transition element M is used to partially replace V. The purpose of adopting this composition design is to improve the hydrogen kinetics performance while maintaining the effective hydrogen storage capacity;

[0027] 2. In terms of preparation method, the deposited Ti 1-x-y-z Mo x V y M z During the stress relief annealing treatment of the alloy, the alloy is subjected to stress relief annealing at 400-600°C for 3-6 hours. The purpose of adopting this condition is to form a multi-principal alloy with ultra-fine grains, so that the alloy has a higher hydrogen absorption and desorption capacity at room temperature, thereby weakening the hysteresis effect.

[0028] In summary, compared with the prior art, the present invention introduces the Mo element and applies additive manufacturing technology to the alloy preparation process to form a multi-principal alloy with ultra-fine grains. Through component design and improved preparation methods, the technical effects of improving hydrogen kinetics, weakening hysteresis effects, and improving the number of hydrogen absorption and desorption cycles and stability are achieved. DETAILED DESCRIPTION

[0029] The technical solutions in some embodiments of the present disclosure are described clearly and completely below. Obviously, the described embodiments are only part of the embodiments of the present disclosure, not all of the embodiments. Based on the embodiments provided by the present disclosure, all other embodiments obtained by ordinary technicians in this field belong to the scope of protection of the present disclosure.

[0030] Example 1

[0031] Using the alloy element content shown in Table 1, according to the chemical formula Ti 0.262 Mo 0.5 V 0.6 (Cr 0.48 Mn 0.04 ) The raw materials were configured, and spherical powders were prepared by gas atomization with a particle size of 53μm. The 3D printing was performed using laser melting deposition manufacturing equipment. The parameters of 3D printing were: laser power 800W, scanning speed 600mm / min, scanning spacing 1mm, and layer height 0.2mm; then the powders were kept at 400℃ for 3h for stress relief annealing, and finally crushed and passed through a 200-mesh sieve, and ball milled under inert gas protection. The ball milling conditions were a ball-to-material ratio of 40:1, a speed of 350 rpm, and a one-hour stop for every two hours of ball milling. The reactor was placed at 300K and vacuumed for 1.5h, and 3.5Mpa hydrogen was flushed in. The alloy could react directly with hydrogen, and the alloy could be fully activated after repeated absorption and desorption of hydrogen three times. The effective hydrogen storage capacity of the alloy at 300K and 3.5Mpa was measured to be 2.5%, and the absorption and desorption of hydrogen could be completed within 15 minutes at room temperature. After 100 cycles of absorption and desorption of hydrogen, the hydrogen storage capacity was 97.2% of the initial saturated hydrogen storage capacity.

[0032] Table 1 Composition (mass fraction) of the Ti-V based hydrogen storage powder of Example 1

[0033] Of Know V Cr Mn 0.262 0.050 0.600 0.048 0.040

[0034] Example 2

[0035] Using the alloy element content shown in Table 2, according to the chemical formula Ti 0.258 Mo 0.002 V 0.45 (Cr 0.24 Fe 0.05) The raw materials were configured, and spherical powders were prepared by gas atomization with a particle size of 60μm. The 3D printing was performed using laser melting deposition manufacturing equipment. The parameters of 3D printing were: laser power 900W, scanning speed 700mm / min, scanning spacing 1.5mm, layer height 0.3mm; 500℃ insulation for 5h stress relief annealing, and finally crushed and passed through a 200-mesh sieve, and ball milled under inert gas protection. The ball milling conditions were a ball-to-material ratio of 40:1, a speed of 350 rpm, and 1 hour of downtime for every 2 hours of ball milling. The reactor was placed at 300K and vacuumed for 1.5h, and 3.5MPa hydrogen was flushed in. The alloy could react directly with hydrogen. After repeated absorption and desorption of hydrogen 3 times, the alloy could be fully activated. The effective hydrogen storage capacity of the alloy at 300K and 3.5MPa was measured to be 2.1%. Hydrogen absorption and desorption can be completed within 10 minutes at room temperature. After 100 cycles of absorption and desorption of hydrogen, the hydrogen storage capacity was 98.1% of the initial saturated hydrogen storage capacity.

[0036] Table 2 Composition (mass fraction) of Ti-V based hydrogen storage powder of Example 2

[0037] Of Know V Want Cr 0.258 0.002 0.450 0.050 0.240

[0038] Example 3

[0039] Using the alloy element content shown in Table 3, according to the chemical formula Ti 0.4 Mo 0.1 V 0.4 (Fe 0.07 Co 0.03 ) Prepare the raw materials, use the gas atomization method to prepare spherical powder with a particle size of 100μm, and use laser melting deposition manufacturing equipment for 3D printing. The parameters of 3D printing are: laser power 1000W, scanning speed 800mm / min, scanning spacing 2mm, layer height 0.4mm; then keep at 600℃ for 6h for stress relief annealing, finally crush and pass through a 200-mesh sieve, and ball mill under inert gas protection. The ball milling conditions are a ball-to-material ratio of 40:1, a speed of 350 rpm, and a stop of 1 hour for every 2 hours of ball milling. The reactor was placed at 300K and vacuumed for 1.5h, and 3.5MPa of hydrogen was flushed in. The alloy can react directly with hydrogen. After repeated absorption and release of hydrogen 3 times, the alloy can be fully activated. The effective hydrogen storage capacity of the alloy at 300K and 3.5MPa was measured to be 1.05%. Hydrogen absorption and desorption can be completed within 5 minutes at room temperature. After 100 cycles of hydrogen absorption and desorption, the hydrogen storage capacity is 98.3% of the initial saturated hydrogen storage capacity.

[0040] Table 3 Composition (mass fraction) of the Ti-V based hydrogen storage powder of Example 3

[0041] Of Know V Want Co 0.400 0.100 0.400 0.070 0.030

[0042] In summary, the hydrogen storage powder prepared by the present invention has higher activation performance while ensuring the hydrogen storage capacity, and the hysteresis effect of hydrogen absorption and desorption is greatly reduced; the number of hydrogen absorption and desorption cycles and stability are greatly improved.

[0043] In the description of this specification, specific features, structures, materials or characteristics may be combined in an appropriate manner in any one or more embodiments or examples.

[0044] The above is only a specific embodiment of the present invention, but the protection scope of the present invention is not limited thereto. Any person skilled in the art can easily think of changes or substitutions within the technical scope disclosed by the present invention, which should be included in the protection scope of the present invention. Therefore, the protection scope of the present invention should be based on the protection scope of the claims.

Claims

1. A Ti-V based hydrogen storage alloy, characterized in that: The general formula of the Ti-V based hydrogen storage alloy is: Ti 1-x-y-z Mo x V y M z , wherein 0.002≤x≤0.1, 0.4≤y≤0.6, 0.05≤z≤0.3, and M is at least one of cobalt, chromium, iron, manganese and nickel.

2. A Ti-V based hydrogen storage alloy according to claim 1, characterized in that: The purity of the raw materials of the Ti-V based hydrogen storage alloy is ≥99.9%.

3. A method for preparing a Ti-V based hydrogen storage alloy as claimed in claim 1 or 2, characterized in that: The following steps are involved: The Ti-V based hydrogen storage alloy is prepared by mixing the metal raw materials according to their contents, preparing spherical powder by a gas atomization method, and then 3D printing, heat treatment and crushing are performed by laser melting deposition equipment to obtain the Ti-V based hydrogen storage alloy.

4. The preparation method according to claim 3, characterized in that: The parameters of the laser melting deposition 3D printing are laser power 800-1000W, scanning speed 600-800mm / min, scanning spacing 1-2mm, and layer height 0.2-0.4mm.

5. The preparation method according to claim 3, characterized in that: The particle size of the spherical powder is 15 to 150 μm.

6. The preparation method according to claim 3, characterized in that: The specific conditions of the heat treatment are: 400-600° C. insulation for 3-6 hours for stress relief annealing.

7. The preparation method according to claim 3, characterized in that: The specific process of the crushing is first crushing and passing through a 200-mesh sieve, and then ball milling under the protection of inert gas. The ball milling conditions are a ball-to-material ratio of 40:1, a rotation speed of 350 rpm, and a 1-hour stop for every 2 hours of ball milling.