Ti–V–Mn based alloys for hydrogen compression system

doi:10.1016/j.jallcom.2005.04.007

Journal of Alloys and Compounds

Volume 400, Issues 1–2, 1 September 2005, Pages 276-280

https://doi.org/10.1016/j.jallcom.2005.04.007 Get rights and content

Abstract

Ti–V–Mn based hydrides are one family of alloys with improved hydrogenation properties and they have a great potential to replace the AB₅ alloys as the sorption materials in hydrogen compression systems, although there still are many problems associated with their use, including unstable reversible hydrogen capacity and unfavorable thermodynamic properties. To gain a better understanding on the effect of the substitution elements and to optimize the alloy composition for high storage capacity, the influence of the alloy stoichiometry was investigated. Ti–Zr–V–Mn alloys were prepared by arc melting technique and were annealed in vacuum at temperature above 900 °C to obtain great sorption properties. Hydrogen absorption and desorption kinetics and PCT characteristics of these alloys at ambient temperature were measured and compared. These hydrogen storage features were also discussed in relation to the effect of alloy element compositions. Ti–Zr–V–Mn alloy cycling behavior was also examined.

Introduction

Hydrogen compression is a key component in hydrogen generators and Hydrogen Research Institute (HRI) believes that metal hydride based hydrogen compression may offer advantages over mechanical compression in terms of scalability (a near-continuous range of outputs is achievable, with highest cost effectiveness in small size systems), reliability and cost.

The use of the metal hydride technology to compress hydrogen implies a judicious strategy to select reactive alloys adapted to each of the compression stages. The experimental measurements of the thermodynamic and kinetic properties of various alloys were carried out. A first selection among various alloys of the AB₅ family allowing us to reach a pressure of 20 atm has been carried out [1], [2]. We have also started studying materials of the AB₂ family and have found interesting performances in terms of speed and flow of compression [3].

The search for increased performances in term of capacity and flow of compression led us naturally towards the study of another family of materials using elements lighter than lanthanum or rare earths: AB₂. This series of alloys, mainly based on the compounds containing titanium manganese (TiMn₂, TiV₂, TiCr₂), meets these aims since they present, in solid–gas reaction, hydrogen capacities and rates of 20–50% higher than those obtained from materials derived from LaNi₅ (Fig. 1, Fig. 2). Unfortunately, we came to realize rather quickly that their thermodynamic instability does not allow considering their use in the compressor at this moment. Our research on these alloys was therefore rather oriented towards the comprehension of the role of the various substitution components on the thermodynamics characteristics (stabilization of the plateaus, hysteresis ratios and hydrogen solubility), kinetics (improvement of the characteristics of loads and discharge) and lifespan.

The Ti-based alloys were studied extensively, because of their potential great sorption capacity at ambient temperature (∼2 wt.%) with high reactivity rates [4], [5], [6], [7], [8], [9], [10], [11], [12]. Moreover, the position of the absorption and desorption plateaus (from 2 to 10 atm) made them good candidates for the compressor project. In accordance with preceding measurements, new materials containing Ti–Zr–V–Mn were synthesized. The goal of these new measurements was to stabilize the storage capacity at 2% after the second cycle. To achieve this goal, certain materials underwent more than 200 cycles, various methods and temperatures of annealing were evaluated and various intermetallic stoichiometry (alloy composition formulations) were characterized. Following these measurements, it appeared that the properties of hydrogenation of this AB₂ type were largely influenced by the quantity of Mn in the material. Manganese has a point of evaporation much lower than other metals. Thus, the synthesis by arc melting is problematic for the reproducibility of the composition of Mn in the structure of the AB₂. However, by proceeding systematically, the optimal quantity of Mn could be determined. Finally, the influence of the composition variations of V and Zr were also measured.

Section snippets

Experimental procedure

The TiMn₂-based alloy samples were prepared from pure elements (purity of Zr = 99%, V = 99.5% and Ti, Mn = 99.9%) by arc melting under argon atmosphere with a non-consumable tungsten electrode and a water-cooled copper tray. Each ingot was melted several times in order to homogenize the alloy composition and then annealed under vacuum of 10⁻³ mbar in quartz tube at least 900 °C for 72 h in order to obtain the equilibrium BCC structure. Chemical composition of the synthesized samples was not analysed,

Results and discussion

Different Ti–Zr–V–Mn alloys with different Mn, V and Zr compositions are synthesized. The hydrogen sorption properties of these intermetallics were examined in order to develop the best alloy formulation having high hydrogen capacity, improved equilibrium plateau level and low hysteresis ratio.

Conclusion

Hydrogen absorbing properties of Ti-based alloys were investigated as a function of metal elements compositions. The modified multicomponent Ti–Zr–V–Mn alloys possess desirable sorption features: high hydrogen storage capacity and adjustable plateau pressure. From these results, it could be determined that the optimal stoichiometry formulation among studied Ti–Zr–V–Mn alloys is: Ti_0.95Zr_0.05V_0.2Mn_1.3. This alloy exhibits the best plateau pressures region needed for the reversible thermal

Acknowledgements

This work was made in partnership with Stuart Energy Systems Inc. and has been supported financially by the Ministère des Ressources Naturelles du Québec and by Natural Resources Canada.

References (13)

Z. Dehouche et al.
J. Alloys Comp
(2005)
S. Semboshi et al.
J. Alloys Comp.
(2003)
S.V. Mitrokhin et al.
J. Alloys Comp.
(2002)
E. Akiba et al.
Intermetallics
(1998)
J.-G. Park et al.
J. Alloys Comp.
(2001)
Y.-H. Xu et al.
Int. J. Hydrogen Energy
(2001)

There are more references available in the full text version of this article.

Cited by (54)

A self-sustaining renewable energy driven hydrogen refuelling system utilising a metal hydride-based compressor
2024, International Journal of Hydrogen Energy
The transition towards carbon-free transportation is only possible by the adoption of renewable energy alternatives. Hydrogen-based transportation is an attractive option considering the availability of the required refuelling infrastructure. A well-established network of hydrogen refuelling infrastructure is important for the widespread commercialization of fuel-cell electric vehicles. The most expensive H₂ refuelling components originate from hydrogen compression. Due to their ability to run on solar thermal energy, a metal hydride hydrogen compressor is used in this study. In this communication, the aim is to present a study on solar thermal based hydrogen compressors for a hydrogen refuelling station. An analytical study is presented on the energy assessment of a metal hydride compressor by considering three candidate pairs of metal hydrides (Pair 1: Ti_0.95Zr_0.05Cr_0.8Mn_0.8V_0.2Ni_0.2/Ti_0.8Zr_0.2Cr_0.95Fe_0.95V_0.1; Pair 2: TiCr_1.55Mn_0.2Fe_0.2/Ti_0.9Zr_0.1Mn_1.4Cr_0.35V_0.2Fe_0.05, Pair 3: La_0.35Ce_0.45Ca_0.2Ni_4.95Al_0.05/Ti_0.8Zr_0.2Cr_0.95Fe_0.95V_0.1) to achieve refuelling pressure of 700 bar. The variation in thermal efficiency of the compressor and thermal energy requirements with changes in heat source temperature, supply pressure and heat losses are presented. Furthermore, the economics of three pairs of alloys for high-pressure compression is compared. It was found that Ti_0.95Zr_0.05Cr_0.8Mn_0.8V_0.2Ni_0.2/Ti_0.8Zr_0.2Cr_0.95Fe_0.95V_0.1 pair has the maximum compressor efficiency of 7.2% at supply pressure and heat source temperature of 25 bar and 150 °C, respectively. In addition, the study revealed that heat losses from the reactor could reduce efficiency by around 12.5%. The economic study revealed that the Ti_0.95Zr_0.05Cr_0.8Mn_0.8V_0.2Ni_0.2/Ti_0.8Zr_0.2Cr_0.95Fe_0.95V_0.1 pair has the least cost for hydrogen compression among the other chosen pairs.
Development and optimization of a two-stage metal hydride hydrogen compressor with AB<inf>2</inf>-type alloys
2023, International Journal of Hydrogen Energy
This study reports the development of a two-stage metal hydride hydrogen compressor (MHHC) capable of compressing hydrogen from 1 to 30 MPa through a temperature change between 20 and 150 °C. AB₂-type hydrogen storage alloys in the C14 Laves phase are employed, where A = Ti and Zr and B = Cr, Mn, and V. The pressure transfer conditions between the two stages are investigated, and the composition of the AB₂ alloys is optimized accordingly: the Mn content x in Ti_0.8Zr_0.2Cr_1.9₋_xMn_xV_0.1 and the Zr content y in Ti₁₋_yZr_yCr_1.2Mn_0.8, for the 1st and the 2nd stage materials, respectively. A laboratory-scale two-stage compressor is fabricated and operated using the selected alloys, whereby hydrogen is successfully compressed to 30 MPa. The compression capacity is analyzed to estimate the useable capacity of the materials. The results of this study can serve as a guide for the design and evaluation of multistage MHHCs.
Effects of Cu doping on the hydrogen storage performance of Ti-Mn-based, AB<inf>2</inf>-type alloys
2023, Chemical Engineering Journal
The Ti-Mn-based AB₂-type hydrogen storage alloy has been widely researched and applied because of their higher hydrogen storage capacity, appropriate service temperature and low cost. However, before this hydrogen storage material becomes a mature technology, the essential issues of activation difficulty and high plateau pressure in hydrogen absorption/desorption process, need to be completely reformed by radical transformation in composition design and structure optimization. This work investigates the microstructure and hydrogen storage performances of Ti_0.8Zr_0.2Mn_0.92Cr_0.87Fe_0.21 + x Cu (x = 0, 3, 5 and 8 wt%) by vacuum arc melting. Profiting from the excellent hydrogen transfer rate and structure optimization, the Ti_0.8Zr_0.2Mn_0.92Cr_0.87Fe_0.21 alloys with the increasing of Cu doping result in the unique C14 Laves phase with the increased lattice volume. As a beneficial result, the decrease of the hydrogen absorption platform of Ti_0.8Zr_0.2Mn_0.92Cr_0.87Fe_0.21 + 8 wt% Cu alloy is accompanied by the increase of the hydrogen desorption platform, thereby reducing the overall hysteresis coefficient of the material. Through Van't Hoff thermodynamic calculation results, it is found that the absolute values of hydrogenation enthalpy and entropy increase with the increasing of Cu doping. It is crucial to doping Cu inside the alloy by the accurate control of stoichiometric proportion and Cu content, which can improve the hydrogen storage performance of the alloy through theoretical analysis and First-principles simulation. This attempt enables new insights into the optimization of the hydrogen storage properties of Ti-Mn-based AB₂-type hydrogen storage alloy, which can be generalized to the design of other new hydrogen storage materials.
Overview of hydrogen compression materials based on a three-stage metal hydride hydrogen compressor
2022, Journal of Alloys and Compounds
Hydrogen, as a clean and renewable energy carrier, is often considered as one of the optimal substitutes for fossil fuels, which could achieve non-polluting transportation in the field of hydrogen fuel cell vehicles (HFCVs). To bring about a guarantee in the long-distance transportation of HFCVs, the safety and ultrahigh pressure of hydrogen charge are required according to the high-pressure onboard tanks, consequently facilitating the development of compressors used in hydrogen refueling stations (HRSs). Compared with traditional mechanical hydrogen compressors, metal hydride hydrogen compressors (MHHCs) hold much more potentials due to their high security, great sealing, and lower maintenance cost. Therefore, the contents associated with MHHCs have been reported by a large number of articles, patents, and books, mainly focusing on the improvement of systematic compression ratio, the modification, and optimization of each-stage hydrogen compression material. In this review, we describe the fundamental aspects of MHHCs firstly, including the working principle of compressors, the thermodynamic and kinetic characteristics of hydrogen compression materials, simultaneously proposing an innovative three-stage MHHC design. The research progress of each-stage materials based on a three-stage MHHC is also discussed, where LaNi₅-based alloys are mainly used in high-density hydrogen storage and primary hydrogen compression, while TiCr₂-based alloys are considered as the candidate alloys in intermediate and final hydrogen compression. Also, ZrFe₂-based alloys possessing extremely high plateau pressures, are promising in the application of the final stage. What’s more, the effects of different alloying elements on the hydrogen storage properties of TiCr₂ are emphatically summarized. Finally, we also discuss the remaining challenges and look forward to the directions of emerging research for hydrogen compression materials.
Study on hydrogen storage property of (ZrTiVFe)<inf>x</inf>Al<inf>y</inf> high-entropy alloys by modifying Al content
2022, International Journal of Hydrogen Energy
(ZrTiVFe)_xAl_y high-entropy alloys are potential hydrogen storage materials because of their intermediate properties of high hydrogen uptake capacity and fast kinetics. In this study, equimolar and non-equimolar (ZrTiVFe)₈₀Al₂₀ and (ZrTiVFe)₉₀Al₁₀ alloys were prepared, and the effect of Al content on the microstructure, element distribution, and hydrogen storage properties of (ZrTiVFe)_xAl_y alloys were investigated. The results show that both alloys are composed of C14 Laves phase, a small amount of tetragonal and HCP phases. With the increase of Al content, the content and the size of C14 Laves phase decrease, the V element content in C14 Laves phase also decreases, which is resulted from the contents of Zr, V, and Fe element constituting the C14 Laves phase decrease. The Ti element can combine with the excessive Al to form a tetragonal phase around the C14 phase, and the growth of the tetragonal phase causes the refinement of the C14 phase. The (ZrTiVFe)₉₀Al₁₀ alloy absorbed 1.3 wt. % H at room temperature, which indicates the better hydrogenation capacity and kinetics. The improvement of hydrogen storage property is resulted from the increased C14 Laves phase, more V element in C14 Laves phase and the severe lattice distortion of (ZrTiVFe)₉₀Al₁₀ alloy. It is found that the (ZrTiVFe)₈₀Al₂₀ alloy can be activated easily with only three cycles, which is caused by the refined Laves phase. After hydrogenated, H atoms are dissolved into the lattice space of C14 Laves phase for both alloys, and crystalline structure is not changed.
Ti-Cr-Mn-Fe-based alloys optimized by orthogonal experiment for 85 MPa hydrogen compression materials
2022, Journal of Alloys and Compounds
Citation Excerpt :
For example, the substitution upon the A-side of TiCr2 with Zr [23] or Sc [24] can improve its activation performance and hydrogen capacity. On the other hand, the partial substitution of the B-side with V [25–27], Mn [28], Fe [29–33], W [34], or Mo [25] can tune the plateau pressure, which is realized by adjusting the relationship between elastic modulus and unit cell volume [28,35]. Furthermore, elements Mn and Fe are often used in the substitution of partial Cr to increase the plateau pressures on the premise of holding a considerable capacity for TiCr2-based alloys, due to their smaller atomic radius than chromium [29,36].
The development of hydrogen storage alloys possessing high plateau pressures for three-stage metal hydride hydrogen compressors (MHHCs), is critically significant for the safe and high-efficiency re-/charging of H₂ in hydrogen refueling stations (HRSs). Herein, Ti-Cr-Mn-Fe-based alloys (Ti_1.04+xCr_2−y-zMn_yFe_z, x = 0.02, 0.04, 0.06, y = 0.2, 0.3, 0.4, z = 0.5, 0.6, 0.7) synthesized by vacuum arc melting, with the single structure of C14 Laves and uniform element distribution, enable the final-stage compression units up to 85 MPa for MHHCs. It is demonstrated that both unit cell volume and maximum hydrogen capacity ( $C_{\max}$ ) increase by the rising amount of Ti or decreasing Mn and Fe in the Ti-Cr-Mn-Fe-based alloys, whereas the dissociation pressures and plateau hysteresis ( $H_{f}$ ) at 223 K are reduced correspondingly, according to the orthogonal results. Meanwhile, as the over-stoichiometric amount of Ti increases, so does the plateau slope ( $S_{f}$ ) of the Ti-Cr-Mn-Fe-based alloys. Under the optimized conditions conducted by the orthogonal results, Ti_1.08Cr_1.3Mn_0.2Fe_0.5 exhibits comprehensively considerable hydrogen absorption/desorption properties, rendering it possible to be one of the most promising final-stage compression materials. Notably, the dehydrogenation enthalpy and entropy for Ti_1.08Cr_1.3Mn_0.2Fe_0.5 is determined to be 22.3 ± 0.3 kJ/mol and 117.8 ± 1.0 J/(mol K), respectively, with a corresponding hydrogen absorption pressure of 14.00 ± 0.52 MPa at 298 K and a dehydriding pressure of 89.19 ± 3.21 MPa at 363 K. Furthermore, the values of $C_{\max}$ , $H_{f}, and S_{f}$ are evaluated as 1.83 ± 0.01 wt%, 0.33 ± 0.01, and 0.72 ± 0.03, respectively, at 223 K.

View all citing articles on Scopus

View full text

Ti–V–Mn based alloys for hydrogen compression system

Abstract

Introduction

Section snippets

Experimental procedure

Results and discussion

Conclusion

Acknowledgements

J. Alloys Comp

J. Alloys Comp.

J. Alloys Comp.

Intermetallics

J. Alloys Comp.

Int. J. Hydrogen Energy