KR101583297B1 - Hydrogen stroge alloy based on titanium-zirconium and production methods thereof - Google Patents

Abstract

The present invention have the ability to absorb and release a large amount of hydrogen in a reversible titanium- relates to a zirconium-based hydrogen storage _{alloy, [Ti (1-x)} Zr x] [Fe (0.3-y) V 0.3 Mn 1 _.65 < / RTI > Al < RTI ID = 0.0 > _y ] < / RTI > X representing the atomic fraction of the alloying elements is in the range of 0.12? X? 0.15, and y satisfies the condition of 0.1? Y? 0.2; Wherein the carbon is contained in a range of 0.6 to 1.5 wt% based on 100 wt% of the total alloy, and a method for manufacturing the same.

Description

FIELD OF THE INVENTION [0001] The present invention relates to a titanium-zirconium-based hydrogen storage alloy and a method for manufacturing the same. BACKGROUND ART < RTI ID =

The present invention relates to a metal hydride alloy capable of reversibly absorbing or releasing a large amount of hydrogen, and more particularly, to a metal hydride alloy capable of exhibiting excellent hydrogen storage ability as well as absorption or release characteristics And more particularly, to a titanium-zirconium-based hydrogen storage alloy and a method of manufacturing the same.

Hydrogen is a source of energy and has several advantages over other media.

That is, there is no pollution, the energy density per weight is high, the water can be produced by decomposing the water, the resources are infinite, the long-term storage is possible, the conversion is easy by the combustion and the electrochemical method, And the ability to utilize water as a by-product with high efficiency.

However, in order to utilize hydrogen, it is necessary to overcome the disadvantage that energy density per volume is low and storage and transportation are inconvenient.

The present invention proposes a hydrogen storage alloy which is a metal hydride alloy having a capability of reversibly absorbing or releasing a large amount of hydrogen as a technology capable of overcoming the shortcomings of hydrogen and realizing the practical use of hydrogen energy I want to.

The hydrogen storage alloy is used for a hydrogen storage material, an energy conversion material, a hydrogen separation and purification material, a fuel cell, and the like, and there is a difference in performance required depending on the intended use. However, It is required that the hydrogen storage amount is large and should show a reaction heat suitable for the operating temperature.

In addition, the wide and flat plateau region, low plateau slope, and dissociation pressure at operating temperature are suitable for the application, there is little hysteresis, which is the difference between the storage and release behavior of hydrogen, High storage and release speeds, strong resistance to impurities such as oxygen or moisture, good durability and thermal conductivity, and low cost alloys.

In the present invention, hydrogen is stored in the form of a metal hydride by reacting with hydrogen, and the stored hydrogen can be reversibly reversed in absorption and release of hydrogen according to changes in temperature or pressure, The present invention proposes a titanium-zirconium-based hydrogen storage alloy having characteristics that the pressure and heat at the time of hydrogen emission can also be used as an energy source.

Compared with conventional high-pressure gas or liquefied hydrogen gas, which can store conventional hydrogen, it can store about 1-2 times as much hydrogen as metal atoms. Therefore, it has a very favorable filling density in terms of volume and is inferior in terms of weight It is disadvantageous, however, because it has a very high energy density per weight of hydrogen, which is very advantageous as an energy source storage method.

On the other hand, the hydrogen-storing alloy is an intermetallic compound composed of a composition of a stable hydrogen-forming element A and an unsupported element B, and an AB5-type rare earth-based alloy improved from a representative hydrogen storage metal LaNi ₅ Laves phase alloys containing Ti and Zr, low cost TiFe alloys, and light Mg alloy, Mg ₂ Ni, have been extensively studied since the 1960s and their applicability has been examined.

Recently, a solid solution alloy having a body-center cubic (bcc) lattice such as a Ti-V-Mn system and a Ti-V-Cr system has attracted attention as a high-capacity alloy due to its hydrogen storage capacity of 3 wt%.

Hydrogen storage alloys that have been researched and developed so far can be classified into three groups according to the crystal structure of the metal constituting the alloy. The first group, AB5 type alloy, is referred to as the first generation hydrogen storage alloy. Although not very much, the storage and release characteristics of hydrogen are excellent, and they are currently being used as a Ni-MH type secondary battery.

The second group, the AB2 type laves-phase alloy, has been actively studied as an electrode material for a secondary battery because of its large hydrogen storage capacity and relatively good storage and release characteristics of hydrogen.

Here, A is a rare earth element composed mainly of Ti, Zr and the like, and B is a first transition element containing Mn, Cr, V, Ni or Fe as a main component and is composed of an AB5 type alloy containing a rare earth metal It is lightweight and has a relatively large amount of hydrogen storage.

At this time, the compound including Ti and Zr has a wide composition range, and it is possible to control the floret pressure by changing the ratio of A and B or to replace the part of A and B with other elements to control the flotato pressure have.

Compared with the first group and the second group, the bcc alloy and the Mg-based alloy, which are the third group, have a problem in the storage and release characteristics of hydrogen compared to a large hydrogen storage amount. Studies are underway to improve storage and release characteristics.

However, the above-mentioned conventional hydrogen storage alloys have a disadvantage in that the effective storage amount of hydrogen is small and the pressure difference at the time of hydrogen absorption or discharge is large when the hydrogen storage alloy is used as a hydrogen storage medium for a hydrogen fuel cell, which has recently become a subject of interest.

Particularly, considering that many application fields of hydrogen fuel cells are related to a moving means such as a vehicle, it is possible to secure a low flat pressure even when the hydrogen storage capacity is increased. Especially, The development of alloys is required.

Korean Patent Publication No. 10-2012-0098312

It is an object of the present invention to solve the above problems and to provide a hydrogen storage device capable of absorbing or releasing hydrogen while maintaining a low flat pressure even when the hydrogen storage capacity is increased and improving hysteresis characteristics and sloping characteristics Zirconium-based hydrogen storage alloy containing titanium-zirconium-iron-vanadium-manganese-aluminum (Ti-Zr-Fe-V-Mn-Al).

In particular, the present invention relates to a titanium-zirconium-iron-vanadium-manganese-aluminum (Ti-Zr-Fe-V-Mn-Al) Zirconium-based hydrogen storage alloy capable of securing a low flatness pressure even when the hydrogen storage capacity is increased and improving the hysteresis and sloping property, and a method of manufacturing the same.

The present invention resides in that hydrogen is reacted with hydrogen to store hydrogen in the form of a metal hydride. The stored hydrogen can be reversibly reversed in absorption and release of hydrogen according to changes in temperature or pressure, Another object of the present invention is to provide a titanium-zirconium-based hydrogen storage alloy capable of utilizing pressure and heat when hydrogen is released as an energy source, and a method of manufacturing the same.

Another object of the present invention is to provide a Laves phase type titanium-zirconium-based hydrogen storage alloy of the AB2 type which can be used for hydrogen storage medium for hydrogen supply of a fuel cell automobile or the like, and a method for producing the same. .

In order to solve the above problems, the titanium-zirconium-base hydrogen storage alloy of the present invention is characterized in that the alloy composition of [Ti _(1-x) Zr _x ] [Fe _(0.3-y) V _0.3 Mn _1.65 Al _y ] And carbon (C), x representing the atomic fraction of the alloying elements is in the range of 0.12? X? 0.15, and y is in the range of 0.1? Y? 0.2.

Here, the carbon may be included in a range of 0.6 to 1.5 wt% based on 100 wt% of the entire alloy.

The present invention also provides a method of manufacturing a titanium-zirconium-based hydrogen storage alloy, comprising: (A) weighing a metal material of Ti, Zr, V and Fe into a graphite crucible; Into a high frequency melting induction furnace, and then dissolving the graphite crucible to prepare a preliminary alloy composition; (B) preparing a final alloy composition by dissolving and mixing metallic materials of Mn and Al in the prealloy composition prepared in the step (A); (C) preparing the final alloy composition as an ingot by pouring it into a mold and subjecting it to a cooling treatment; And a control unit.

In the step (A), 11 to 15 parts by weight of Zr, 15 to 20 parts by weight of V, and 8.5 to 11 parts by weight of Fe are weighed and added to 45 to 50 parts by weight of Ti; In the step (B), 100 to 110 parts by weight of Mn and 3.5 to 5 parts by weight of Al may be weighed out to 45 to 50 parts by weight of Ti.

Here, the ingot is produced in the (C) step _{is, [Ti (1-x)} Zr x] Carbon (C as non-metal elements in the alloy composition of the _{[Fe (0.3-y) V} 0.3 Mn 1 .65 Al y] ); ≪ / RTI > X representing the atomic fraction of the alloying elements is in the range of 0.12? X? 0.15, and y satisfies the condition of 0.1? Y? 0.2; The carbon may be included in the range of 0.6 to 1.5 wt% based on 100 wt% of the entire alloy.

According to the present invention, the atomic fraction of titanium, zirconium, iron, and aluminum with respect to the elements including titanium-zirconium-iron-vanadium-manganese-aluminum (Ti-Zr-Fe-V-Mn- It is possible to provide a titanium-zirconium-based hydrogen storage alloy capable of securing a low flat pressure even when the hydrogen storage capacity is increased, and improving hysteresis and sloping characteristics.

The present invention can store hydrogen in the form of a metal hydride by reacting with hydrogen, and the stored hydrogen can be reversibly reversed in absorbing and releasing hydrogen according to changes in temperature or pressure, It is possible to achieve the usefulness of utilizing the pressure and heat of hydrogen emission as an energy source.

The present invention can provide a titanium-zirconium-based hydrogen storage alloy which can be usefully used as a hydrogen storage medium for hydrogen supply in a fuel cell automobile or the like.

1 is a block flow diagram illustrating a process for producing a titanium-zirconium-based hydrogen storage alloy according to the present invention.
2 is a graph showing a pressure-composition-temperature (PCT) characteristic of the titanium-zirconium-based hydrogen storage alloy of Example 1 according to the present invention.
FIG. 3 is a graph showing a pressure-composition-temperature (PCT) characteristic of the titanium-zirconium-based hydrogen storage alloy of Example 2 according to the present invention.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, preferred embodiments of the present invention will be described with reference to the accompanying drawings. The present invention will become more apparent from the following detailed description when taken in conjunction with the accompanying drawings.

However, it should be understood that the present invention may be embodied in many different forms and should not be construed as limited to the embodiments set forth herein.

In the titanium-zirconium-based hydrogen storage alloy according to the present invention,

Has an alloy formula represented by [Ti _(1-x) Zr _x ] [Fe _(0.3-y) V _0.3 Mn _1.65 Al _y ], and contains carbon (C) as a nonmetal component.

Ti represents titanium, Zr represents zirconium, Fe represents iron, V represents vanadium, Cr represents chromium, Mn represents manganese, and Al represents aluminum.
In this case, 45 to 50 parts by weight of Ti is used, and based on the amount of the Ti metal material used, 11 to 15 parts by weight of Zr, 15 to 20 parts by weight of V, 8.5 to 11 parts by weight of Fe, 100 to 110 parts by weight of Mn, To 5 parts by weight are used.

Here, x and y are atomic fractions of elements constituted respectively, x satisfies 0.12? X? 0.15, and y satisfies 0.1? Y? 0.2.

In addition, the non-metal component is carbon (C) is _{[Ti (1-x) Zr} x] [Fe (0.3-y) V 0.3 Mn 1 .65 Al y] can be defined by the value contained in total, based on the weight of the alloy having But may be included in the range of 0.6 to 1.5 wt% based on 100 wt% of the entire alloy.

In order to exhibit excellent properties of the hydrogen-storing alloy, it is preferable to use a metal having a high purity as much as possible for the above-mentioned compositional elements. It is preferable to use titanium, zirconium (Zr), electrolytic iron (Fe), vanadium (Mn), and aluminum (Al).

On the other hand, the titanium-zirconium-based hydrogen storage alloy according to the present invention having the chemical formula formed by the above-described metal elements can be produced by a manufacturing process as shown in FIG.

Ti, Zr, V and Fe are respectively weighed into a graphite crucible, the graphite crucible containing the four metal materials is put in a high frequency melting induction furnace, and then melted to prepare a preliminary alloy composition (S10) .

At this time, the metal material is preferably added in an amount of 11 to 15 parts by weight of Zr, 15 to 20 parts by weight of V, and 8.5 to 11 parts by weight of Fe relative to 45 to 50 parts by weight of Ti.

The metal alloy of Mn and Al is added to the preliminary alloy composition prepared in the step S10 and then dissolved to prepare a final alloy composition (S20).

At this time, the metal material is preferably added in an amount of 100 to 110 parts by weight of Mn and 3.5 to 5 parts by weight of Al relative to 45 to 50 parts by weight of Ti.

Herein, the metal materials of Mn and Al are respectively weighed, placed in a graphite crucible, dissolved by using a high-frequency melting induction furnace, and then mixed with a preliminary alloy composition to prepare a final alloy composition. In some cases, graphite having a preliminary alloy composition Mn and Al weighed in the crucible may be added and dissolved in a high-frequency dissolution induction furnace to prepare a final alloy composition.

The final alloy composition prepared through the step S20 is poured into a mold and subjected to a cooling treatment to produce an ingot (S30).

In this way, the titanium is formed by the chemical formula contains a carbon (C) to non-metallic components in the alloy composition of _{[Ti (1-x) Zr} x] [Fe (0.3-y) V 0.3 Mn 1 .65 Al y] - zirconium-based Hydrogen storage alloy can be produced, x can satisfy 0.12? X? 0.15, and y can satisfy 0.1? Y? 0.2.

In addition, the non-metal component is carbon (C) is essential to the process of melting a metallic material by use of a graphite crucible _{[Ti (1-x) Zr} x] [Fe (0.3-y) V 0.3 Mn 1 .65 Al _y ].

In addition, in steps S10 and S20 for dissolving the metal material, the metal oxide is formed as a by-product by performing the reaction in an inert gas atmosphere such as argon or helium or a vacuum atmosphere, thereby preventing the performance of the hydrogen storage alloy from deteriorating .

≪ Example 1 >

In order to prepare a titanium-zirconium-based hydrogen storage alloy having the following chemical formula 1, a metal material as shown in Table 1 below was used, and a hydrogen storage alloy was prepared through the above-described manufacturing process.

The amount of the metal materials used for producing the titanium-zirconium-based hydrogen storage alloy represented by the formula (1) metal Amount used (parts by weight) Ti 48 Zr 12 Fe 9.4 V 17.1 Mn 102 Al 4.5

The titanium-zirconium-based hydrogen storage alloy was prepared from the compositional ingredients of the metal materials shown in Table 1, and the hydrogen storage alloy as shown in Chemical Formula 1 was obtained.

≪ Example 2 >

To prepare the titanium-zirconium-based hydrogen storage alloy having the following chemical formula 2, a metal material as shown in Table 2 below was used, and the hydrogen storage alloy was prepared through the above-described manufacturing process.

The amount of the metal materials used for producing the titanium-zirconium-based hydrogen storage alloy represented by the formula (2) metal Amount used (parts by weight) Ti 46 Zr 14.3 Fe 10.6 V 16.9 Mn 100.8 Al 4

A titanium-zirconium-based hydrogen storage alloy was prepared from the compositional ingredients of the metal materials shown in Table 1, and the hydrogen storage alloy as shown in Chemical Formula 2 was obtained.

On the other hand, PCT (pressure-composition-temperature) measurement of the titanium-zirconium-based hydrogen storage alloy obtained through Examples 1 and 2 showed the graph characteristics as shown in FIG. 2 and FIG. 3, respectively.

2 and 3, it can be seen that the pressure difference in the plateau region when storing and releasing hydrogen is as small as 2 bar to 5 bar, which means that the storage in the plateau region of a conventional hydrogen- Considering that the pressure difference between the time of discharge and the discharge is more than 3 bar to 10 bar, it shows very good storage and discharge characteristics and shows excellent hysteresis and sloping characteristics.

Claims (5)

In the titanium-zirconium-based hydrogen storage alloy,
(C) as a non-metallic component in an alloy composition represented by [Ti _(1-x) Zr _x ] [Fe _(0.3-y) V _0.3 Mn _1.65 Al _y ];
The amount of Ti used is 45 to 50 parts by weight based on the alloy composition. 11 to 15 parts by weight of Zr, 15 to 20 parts by weight of V, 8.5 to 11 parts by weight of Fe, 100 to 110 parts by weight of Mn, To 5 parts by weight;
X representing the atomic fraction of the alloying elements is in the range of 0.12? X? 0.15, and y satisfies the condition of 0.1? Y? 0.2;
Wherein the carbon is contained in a range of 0.6 to 1.5 wt% based on 100 wt% of the total alloy.
delete A method for producing a titanium-zirconium-based hydrogen storage alloy,
(A) Weighing a metal material of Ti, Zr, V and Fe into a graphite crucible, injecting the graphite crucible containing the four metal materials into a high frequency dissolution inducing furnace, and dissolving them to prepare a preliminary alloy composition ;
(B) preparing a final alloy composition by dissolving and mixing metallic materials of Mn and Al in the prealloy composition prepared in the step (A);
(C) preparing the final alloy composition as an ingot by pouring it into a mold and subjecting it to a cooling treatment; / RTI >
In the step (A), 11 to 15 parts by weight of Zr, 15 to 20 parts by weight of Vr and 8.5 to 11 parts by weight of Fe are weighed and added based on 45 to 50 parts by weight of Ti;
In the step (B), 100 to 110 parts by weight of Mn and 3.5 to 5 parts by weight of Al are weighed and added based on 45 to 50 parts by weight of Ti;
The ingot produced in the step (C)
The carbon added to the process of dissolving the metal material by the use of the graphite crucible as a non-metal component in the alloy composition represented by [Ti _(1-x) Zr _x ] [Fe _(0.3-y) V _0.3 Mn _1.65 Al _y ] (C), < / RTI >
X representing the atomic fraction of the alloying elements is in the range of 0.12? X? 0.15, and y satisfies the condition of 0.1? Y? 0.2;
Wherein the carbon is contained in a range of 0.6 to 1.5 wt% based on 100 wt% of the total alloy. delete delete

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