JP3350691B2 - High activation and stabilization of hydrogen storage metal - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for pulverizing a metal material that absorbs hydrogen and simultaneously activating a surface or a surface layer, and deactivating a corrosive or poisonous gas, liquid or vapor. And a stabilizing treatment method.

[0002]

2. Description of the Related Art Conventionally, in order for a hydrogen storage metal material to stably store and release hydrogen, an initial activation process at high temperature, high pressure, high vacuum or the like is required. In the case of, a vacuum degassing treatment is performed at 350 ° C.
It is necessary to repeat the occlusion and desorption of hydrogen at least 10 times at a. In the case of a La-Ni alloy, vacuum degassing is performed at 80 to 100 ° C., and occlusion and desorption of hydrogen is performed at 1 to 3 MPa at least 10 times. Need to be repeated.

[0003] Further, even if the hydrogen storage metal material once activated is exposed to the atmosphere again, it is severely oxidized and loses its hydrogen storage capacity. Further, dust explosion due to ignition or ignition may occur. Due to the danger, sufficient care was required for handling.

[0004] Further, the activated hydrogen storage metal material has a very active surface, and thus, in addition to hydrogen, for example, a trace amount of carbon monoxide, hydrogen sulfide, water vapor, oxygen and the like is contained in the process. In such a case, the gases poison the surface significantly, making it impossible to stably store and release hydrogen.
High purity hydrogen gas was required for the process gas.

[0005] Further, even when originally used at less than 1 MPa, an initial activation treatment requires a high pressure of 1 MPa or more, so that excessive capital investment in compliance with the High Pressure Gas Control Law has been required.

As described above, in using the hydrogen storage metal material, workability, instability, danger of handling, high cost, and the like of the initial activation treatment have been practically problematic.

In order to solve the above problems, a surface treatment method using a chemical solution, for example, a microencapsulation method of a hydrogen storage metal material using copper or nickel using an electroless plating method,
A method for highly activating or stabilizing a hydrogen storage metal material by surface treatment in an aqueous alkaline solution containing fluorine ions has been proposed.

However, the method of treating with a chemical solution includes:
There are the following problems. A delicate pH adjustment is required to obtain the desired surface layer. Requires large equipment for throughput. It takes time for final drying. Waste liquid treatment after treatment is troublesome. In particular, a pulverization treatment by hydrogenation in the case of performing a stabilization treatment is required in another process. High processing cost. From the above points, it is difficult to expect efficient production in industrial production, and the problem has not yet been sufficiently solved.

[0009]

SUMMARY OF THE INVENTION In order to solve the above-mentioned problems, the present invention activates the surface of a hydrogen-absorbing metal material with respect to hydrogen without using a chemical solution, and uses a non-chemical material to prevent surface poisoning. It can be activated and stabilized, and in industrial production,
An object of the present invention is to provide a method for highly activating and stabilizing a hydrogen storage metal material that can be efficiently produced.

[0010]

In order to solve the above-mentioned problems, a first method for highly activating and stabilizing a hydrogen-absorbing metal material according to the present invention is to fill a hydrogen-occluding metal material into a reaction vessel, , And simultaneously introduce a fluorine-based gas and a hydrogen gas such as hydrogen fluoride gas, ammonium acid fluoride and ammonium fluoride gas, and nitrogen trifluoride gas into the reaction vessel at a required pressure. Then, the hydrogen storage metal material is pulverized, and a film containing a metal fluoride as a main component is formed on the surface by vapor phase growth, so that at least the surface or the surface layer is highly activated with respect to hydrogen molecules. And deactivates substances having surface poisoning other than hydrogen molecules.

The second method for highly activating and stabilizing a hydrogen storage metal material according to the present invention is directed to a reaction vessel filled with the hydrogen storage metal material treated by the first high activation and stabilization method. Further, a fluorine-based gas and a hydrogen gas are simultaneously introduced under the required pressure and temperature conditions, and the storage and release of hydrogen are repeatedly performed on the hydrogen storage metal material, thereby further promoting the pulverization of the hydrogen storage metal material. In addition, a film containing metal fluoride as a main component is formed on the surface or the surface layer of the metal material to activate hydrogen molecules highly and deactivate substances having surface poisoning other than hydrogen molecules. It is characterized by doing.

The third method for highly activating and stabilizing a hydrogen-absorbing metal material of the present invention comprises the step of treating the hydrogen-absorbing metal material in a reaction vessel treated by the first or second high-activity and stabilizing method. ,
Heat treatment with an inert gas or hydrogen gas at a temperature condition appropriate for the metal material to homogenize the film containing metal fluoride as a main component, and to further activate hydrogen molecules,
It is characterized in that substances having surface poisoning other than hydrogen molecules are further deactivated.

The hydrogen storage metal material before filling the reaction vessel in the first to third hydrogen storage metal materials with high activity and stabilization is a material such as powder or ingot, or a hydrogen storage metal. It may be any of a matrix composite material, an intermediate product, or a finished product.

According to the first method for activating and stabilizing a hydrogen-absorbing metal material according to the first aspect of the present invention, the surface or surface layer of the hydrogen-absorbing metal material is vapor-phased by a mixed gas of a fluorine-based gas and a hydrogen gas. At the same time as the metal fluoride film is formed by the growth, hydrogen absorption from the metal fluoride film causes cracks and micronization of the hydrogen storage metal material, and the metal fluoride film continues to be formed on the newly formed surface. You. Therefore, eventually, a metal fluoride film is formed on the entire surface of the hydrogen storage metal material, and becomes highly active against hydrogen molecules. The initial activation of the hydrogen storage metal material, which required high temperature, high pressure, and high vacuum, is performed at low temperature. ,
Low pressure, no vacuum evacuation, and the metal fluoride film formed on the surface is a stable compound layer, so there is no danger of ignition or ignition in the atmosphere and surface poisoning other than hydrogen molecules Being inert to the substance, handling dangers are resolved and maintenance costs in equipment, production and transport that have previously been required to avoid the dangers are greatly reduced.

Further, the first method for activating and stabilizing a hydrogen-absorbing metal material according to the first aspect of the present invention is a method for compounding and pulverizing by hydrogen absorption in a gas phase using a mixed gas of a fluorine-based gas and a hydrogen gas. Since the reactions are performed simultaneously, unlike conventional chemical processing, they can be processed simultaneously in the same facility and have high productivity, and can be used on a large-scale production scale without requiring large-scale facilities and complicated processes, and processing costs are high. It is possible to significantly reduce

Further, according to the second method for activating and stabilizing a hydrogen-absorbing metal material of the present invention, the hydrogen-absorbing metal material which has been finely divided and whose surface has a metal fluoride film formed thereon can be used. Since the occlusion and release of hydrogen are repeated, a fine powder treatment and a metal fluoride film are formed on the newly formed surface, so that the hydrogen molecules have higher activity and are stabilized.

Further, according to the third method for highly activating and stabilizing a hydrogen-absorbing metal material of the present invention, the surface is pulverized by the above-mentioned first or second processing method and the surface thereof is treated with metal fluoride. The heat treatment is performed on the hydrogen-absorbing metal material on which the film is formed at a temperature condition suitable for the metal material, so that the metal fluoride film is homogenized and the hydrogen-occluding metal material is further stabilized.

[0018]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The basic configuration of the present invention and a specific embodiment will be described. First, the basic configuration will be described. The present invention is basically, on the surface of the hydrogen storage metal material,
A metal fluoride film is formed by vapor phase growth, and at the same time, a pulverization process is performed by absorbing hydrogen from the metal fluoride film. The hydrogen storage metal material is conventionally conventionally known as a hydrogen storage alloy. Are used in a wide range, and rare earth alloys and Mg-based alloys are shown as typical examples. The processing conditions for forming a metal fluoride film on the surface of the hydrogen storage metal material by vapor phase growth and simultaneously proceeding the pulverization treatment by hydrogen storage are as follows: pressure-hydrogen concentration-specific to the hydrogen storage metal material to be processed. It is necessary to use a mixture ratio of hydrogen gas and fluorine-based gas in consideration of temperature-dependent characteristics. The processing gas is a mixed gas of hydrogen gas and any fluorine-based gas such as hydrogen fluoride gas, ammonium acid fluoride and ammonium fluoride gas, and nitrogen trifluoride gas. A mixed gas with hydrogen fluoride gas is preferred. The concentration of fluorine in the mixed gas is usually selected in the range of 0.1 to 70 vol%, preferably 1 to 40 vol%.

The processing temperature and the processing pressure are usually determined in consideration of the pressure-hydrogen concentration-temperature characteristics of the hydrogen absorbing metal material, and the processing temperature is usually from room temperature to 350 ° C., and the processing pressure is from atmospheric pressure to 5MPa.
a, preferably, the treatment is performed under a temperature condition in which the concentration of hydrogen absorbed in the treated hydrogen storage metal material is 90% or more at a supply pressure of less than 1 MPa. The time required for forming the metal fluoride film is usually about 10 to 360 minutes.
The fluorination reaction of forming a metal fluoride film on the surface of the hydrogen storage metal material depends on the reaction characteristics between the hydrogen storage metal material and fluorine.
Since the reaction proceeds more easily as the processing temperature is higher, it is desirable that the hydrogen storage metal material having a higher processing temperature condition be processed with a lower fluorine concentration in the processing gas, and the higher the processing temperature and the higher the fluorine concentration in the processing gas. If it is high, the fluorination treatment proceeds more than necessary, and various properties inherent in the hydrogen storage metal are impaired, so care must be taken.

FIG. 1 is a schematic view showing an example of a processing apparatus for simultaneously fluorinating the above-mentioned hydrogen-absorbing metal material with pulverization by hydrogen storage. 1 is a reaction vessel filled with the hydrogen-absorbing metal material, and 2 is a reaction vessel. An electric furnace 3 for heating the vessel 1 is a gas supply system connected to the gas introduction line 4 of the reaction vessel 1.
Built-in switching valve, flow control device, etc. 5 is an inert gas storage cylinder upstream of the gas supply system 3, 6 is a raw material gas storage cylinder of another system, and 7 is a vacuum exhaust device of the reaction vessel 1.

In the case where the hydrogen storage metal material is pulverized by this processing apparatus and a metal fluoride film is formed on the surface at the same time,
Any inert gas such as N ₂ , Ar, He or the like in the inert gas storage cylinder 5 is flowed by the gas supply system 3 through the gas introduction line 4 into the reaction vessel 1 at about 10 L / min. , The inside of the reaction vessel 1 is replaced with an inert gas, or the inside of the reaction vessel 1 is evacuated to 1 torr or less by the vacuum evacuation device 7. Next, the entire reaction vessel 1 is heated to a required processing temperature by the electric furnace 2. Next, a gas mixture of the hydrogen gas in the raw material gas storage cylinder 6 and any fluorine-based gas such as hydrogen fluoride gas, ammonium acid fluoride and ammonium fluoride gas, and nitrogen trifluoride gas is supplied. System 3
1MP into the reaction vessel 1 through the gas introduction line 4
The pressure is lower than a, and a metal fluoride film is formed on the surface of the hydrogen storage metal material in the reaction vessel 1, and the pulverization treatment by hydrogen absorption from the metal fluoride film is performed simultaneously. Normally, a single formation of the metal fluoride film and pulverization treatment are sufficient, but especially when used in a highly toxic or corrosive environment, repeated absorption and release of hydrogen with the mixed gas several times Then, pulverization is further promoted, and a metal fluoride film is formed on the surface.
After performing the predetermined treatment, the inert gas is again supplied to the reaction vessel 1.
And the mixed gas remaining in the reaction vessel 1 is purged. Then, in order to homogenize the metal fluoride film formed on the surface of the hydrogen storage metal material, heat treatment is performed in an inert gas or a hydrogen gas.

The hydrogen storage metal material thus treated is
A metal fluoride film is formed on all of the cracks generated by hydrogen storage and the newly formed surface due to micronization, and it becomes a hydrogen storage metal material that is effective and has a large specific surface area, is highly active against hydrogen molecules, and has a surface coating other than hydrogen molecules. It is inactive against poisons and corrosive substances.

Next, a specific embodiment of the method for highly activating and stabilizing the hydrogen storage metal material of the present invention will be described. Example 1 A reaction vessel was filled with 10 g of a hydrogen storage alloy LaNi _4,7 Al _0.3 , which was mechanically pulverized to 500 μm or less, and then N ₂ gas was flowed while the reaction vessel was heated to 80 ° C. While replacing the gas in the reaction vessel, a mixed gas of hydrogen gas and 10 vol% hydrogen fluoride gas was introduced into the reaction vessel at a pressure of 0.98 MPa until hydrogen was no longer absorbed, and hydrogen was absorbed for one hour. At the same time, a fluoride film was formed. After the treatment, most of the samples were pulverized to a particle size of 38 μm or less. When the sample was subjected to structural analysis by X-ray diffraction, peaks of LaNi ₅ and LaF ₃ were confirmed. Therefore, a compound of lanthanum fluoride of La and fluorine in the mother alloy while the mother alloy was sufficiently left. It was confirmed that was formed. The analysis profile is shown in FIG.

The characteristics of the sample treated in Example 1 as a hydrogen storage metal material are shown below. (Evaluation 1) The initial hydrogen storage characteristics of the sample treated according to Example 1 and the untreated sample as a comparative example were measured under the same conditions. FIG. 3 shows the time on the horizontal axis and the weight ratio (wt%) of the hydrogen absorbed in the alloy to the alloy, and the reaction conditions were as follows: the alloy temperature was constant at 40 ° C .;
The operation was performed for 30 minutes from 01 torr, and performed at a hydrogen introduction pressure of 1 MPa. The sample on which the fluoride film was formed was stored in dry air at 40 ° C. for 30 days after the treatment, and the untreated sample was once pulverized mechanically to a size of 500 μm or less, and then fluorinated. The sample was stored under the same conditions as the sample on which the film was formed. As a result, the sample treated according to Example 1 started occlusion immediately after the introduction of hydrogen, and was substantially equilibrated in about 20 minutes, and the occluded amount at that time was about 1.25 wt%. On the other hand, the untreated product gradually started to occlude from about one hour after the introduction of hydrogen, but the occluded amount did not reach 0.2 wt% even after 3 hours. The sample thus treated according to Example 1 has a faster initial hydrogenation reaction rate than the untreated sample and is hardly affected by oxidation, even when stored in dry air at 40 ° C. for 30 days. , And maintained a stable and highly activated surface state.

Example 2 500 mechanically placed in a reaction vessel
Hydrogen storage alloy LaNi _4,7 Al ground to less than μm
The reaction vessel was filled with 10 g of _0.3 g, and then, while the reaction vessel was heated to 60 ° C., the gas in the reaction vessel was replaced while flowing N ₂ gas. Then, hydrogen gas and 3 vol% hydrogen fluoride were introduced into the reaction vessel. A gas mixture with the gas is introduced at a pressure of 0.98 MPa until hydrogen is no longer absorbed, and a hydrogen fluoride film is formed at the same time as hydrogen absorption for 10 minutes.
Evacuated to rr. The introduction of the mixed gas and the evacuation were defined as one cycle, and a total of 10 cycles were performed. After the treatment, the average particle size of the sample was around 15 μm in median value. Further, when the sample was subjected to structural analysis by X-ray diffraction, peaks of LaNi ₅ and LaF ₃ were confirmed as in Example 1.

(Evaluation 2) A comparative test was carried out on an untreated sample to determine whether the sample treated in Example 2 had resistance to poisoning of carbon monoxide, which is the most susceptible to hydrogen storage metal materials. The results are shown in FIG. In FIG. 4, the horizontal axis indicates the number of cycles due to hydrogen storage and release, and the vertical axis indicates the rate of change in the hydrogen storage amount. In the comparative test, first, the two types of samples were evacuated to 80 deg. C to 0.1 torr, and then a 7 N high-purity hydrogen gas was introduced at an introduction pressure of 2.5
The activation treatment was performed three times under the condition of MPa. After the activation treatment, a hydrogen gas containing 1000 ppm of carbon monoxide was stored at a temperature of 80 ° C. and an introduction pressure of 1 MPa, and an occlusion rate of 1 SCCM / g.
-Alloy, and then released at a temperature of 80 ° C. to a release rate of 1 SCCM / g-alloy, and the change in the effective hydrogen transfer amount with the number of cycles was observed. as a result,
Untreated sample has an effective hydrogen transfer amount of 0 wt at the 5th cycle
%, And 0% of the initial storage amount, completely losing the original characteristics of the hydrogen storage metal material. On the other hand, the sample treated in Example 2 stably exhibited an effective hydrogen transfer amount of about 1.0 wt% even at the 50th cycle, and maintained an occluded amount of about 95% of the initial hydrogen absorbed amount. Therefore, it was confirmed that the hydrogen storage metal material treated in Example 2 was inactivated against carbon monoxide, which is most susceptible to poisoning.

Example 3 500 mechanically placed in a reaction vessel
₁₀ g of a hydrogen storage alloy Mg ₂ Ni pulverized to not more than μm, and then N ₂ was heated to 200 ° C.
The gas in the reaction vessel is replaced while the gas is flowing, and then a mixed gas of hydrogen gas and 5 vol% hydrogen fluoride gas is introduced into the reaction vessel at a pressure of 0.98 MPa until hydrogen is no longer occluded. A fluoride film was formed at the same time as hydrogen absorption for one hour, and then the temperature of the reaction vessel was raised to 350 ° C. and heat treatment was performed for one hour. Thereafter, the reaction vessel was cooled to room temperature, and the inside of the reaction vessel was replaced with N ₂ gas. Thereafter, a sample was taken out of the reaction vessel in the atmosphere, and it was confirmed that there was no ignition or ignition. In addition, the sample treated according to the third embodiment
After degassing to 0 ° C. and evacuation to 0.01 torr, the surface of the sample was subjected to elemental analysis using an energy dispersive X-ray analyzer, and it was confirmed that fluorine was present on the sample surface. The analysis profile is shown in FIG.

(Evaluation 3) The amount of hydrogen occluded in the sample treated in Example 3 was measured. In the measurement, after the temperature of the sample filled in the reaction vessel was raised to 350 ° C., the sample was discharged into a reservoir tank which was evacuated to 0.01 torr in advance, and the amount of hydrogen released from the sample was calculated based on the pressure equilibrium value at that time. As a result, the release amount was about 3 wt%. Further, after releasing the hydrogen occluded during the formation of the fluoride film, vacuum evacuation was performed at a temperature of 350 ° C. to 0.01 torr, and hydrogen was occluded again at a temperature of 250 ° C. and an introduction pressure of 0.98 MPa. FIG. 6 shows the result. FIG.
Indicates the hydrogen storage time on the horizontal axis, and the amount of hydrogen stored in the sample on the vertical axis. As can be seen from FIG. 6, storage started immediately after the introduction of hydrogen, and reached approximately equilibrium in about 3 minutes, at which time the amount of stored hydrogen was 3.3 wt%. Therefore, Embodiment 3
The hydrogen-storing metal material treated in the above can be safely handled even in the atmosphere, even if the temperature of the hydrogen-storing metal material is lower than the hydrogen release temperature even in the state of storing hydrogen,
Moreover, the stored hydrogen is easily released by heating to a temperature sufficient for release, and the hydrogen storage characteristics from the second time have the same hydrogen storage characteristics as the untreated sample that has already been activated several times. Was confirmed.

[0029]

As described above, the method for highly activating and stabilizing a hydrogen storage metal material according to the present invention uses a mixed gas of a hydrogen gas and a fluorine-based gas to cover the surface of the hydrogen storage metal material by gas phase growth. Simultaneously with the formation of the oxidized film, the formation of the fluoride film accelerates the hydrogen storage and causes the hydrogen storage metal material to be pulverized and cracked. Further, the formation of a fluoride film continues on a new surface such as a crack generated by hydrogen absorption. As described above, in this treatment method, the formation of the fluoride film and the hydrogen absorption occur continuously, and finally the fluoride film is formed on the entire surface of the hydrogen storage metal material. And stabilize. Therefore, the initial activation of the hydrogen-absorbing metal material, which required storage and desorption at high temperature, high pressure, and high vacuum 10 times or more, can be performed at low temperature, low pressure, without vacuum evacuation, and the fluoride film formed on the surface Is a very stable compound, so it has very little effect of oxygen and moisture in the atmosphere even when exposed to the air.Therefore, there is no danger of ignition or dust explosion due to ignition due to a rapid oxidation reaction. The same applies to the state where occlusion is performed. In addition, since it is inactive against substances having surface poisoning and corrosion other than hydrogen molecules, dangers in handling are solved, and equipment that has been required to avoid dangers, Maintenance costs in production and transportation can be significantly reduced.

Further, the method for highly activating and stabilizing a hydrogen-absorbing metal material of the present invention is characterized in that the compound reaction and the pulverization reaction with hydrogen are simultaneously performed in the gas phase with a mixed gas of hydrogen gas and fluorine-based gas. Since the process can be carried out in the facility, the productivity is high, large-scale facilities and complicated processes are not required, it is possible to cope with mass production scale, and the processing cost can be greatly reduced.

Further, the hydrogen storage metal material treated by the method for highly activating and stabilizing the hydrogen storage metal material of the present invention has a required particle diameter in advance in order to maintain a very stable state in the atmosphere. Even if it is stored in the air in the adjusted state, it immediately shows the inherent hydrogen storage characteristics of the hydrogen storage metal material at low temperature and low pressure at the time of use. It is possible to minimize the startup loss of a plant or the like. In addition, since it can be handled in the atmosphere even when it is storing hydrogen, it is not necessary to tightly fill it in a metal pressure-resistant container when storing and transporting hydrogen in a metal material storing hydrogen. Hydrogen can be safely transported with simple packaging.

Further, since the surface-treated hydrogen storage metal material is inactive to substances other than hydrogen molecules, only hydrogen can be stably recovered from a gas having a low hydrogen concentration. When used in hydrogen storage tanks for fuel storage, hydrogen transport, heat transport, etc., it can maintain stable performance for a long time, and can be used as a negative electrode material for small and large nickel-metal hydride secondary batteries In this case, the initial charge-discharge characteristics, corrosion resistance to the electrolyte, and cycle life are excellent.

[Brief description of the drawings]

FIG. 1 is a schematic view of an example of a processing apparatus for performing a method for highly activating and stabilizing a hydrogen storage metal material of the present invention.

FIG. 2 is a view showing an analysis profile obtained by performing a structural analysis on a hydrogen storage metal material treated according to Example 1 of the present invention by an X-ray analysis method.

FIG. 3 is a diagram showing the relationship between the time required for hydrogen storage and the amount of hydrogen storage of a sample treated according to Example 1 of the present invention and an untreated sample.

FIG. 4 is a diagram showing the relationship between the number of cycles of hydrogen absorption and release and the rate of change in the hydrogen storage amount of the sample treated and the untreated sample in Example 2 of the present invention.

FIG. 5 is a diagram showing an analysis profile obtained by performing an elemental analysis on a sample surface of a hydrogen storage metal material treated according to Example 3 of the present invention using an energy dispersive X-ray analyzer.

FIG. 6 is a diagram showing a relationship between a hydrogen storage time and a hydrogen storage amount of a sample treated in Example 3 of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Reaction container 2 Electric furnace 3 Gas supply system 4 Gas introduction line 5 Inert gas storage cylinder 6 Raw material gas storage cylinder 7 Vacuum exhaust system

──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Manabu Ito 2-5-13, Sanno, Ota-ku, Tokyo Inside Benkan Corporation (72) Inventor Toru Nakazawa 2-5-13, Sanno, Ota-ku, Tokyo Bencan Corporation (72) Inventor Hirohisa Kikuyama 7-227, Kaiyama-cho, Sakai-shi, Osaka Pref. In Hashimoto Chemicals Co., Ltd. Sanpo Plant (72) Inventor Ryoji Hirayama 7-227, Kaiyama-cho, Sakai-shi, Osaka Pref. 56) References JP-A-7-268649 (JP, A) JP-A-52-86921 (JP, A) (58) Fields investigated (Int. Cl. ⁷ , DB name) C01B 3/00

Claims (4)

(57) [Claims] 1. A reaction vessel is filled with a hydrogen storage metal material,
After heating to the required temperature, a fluorine-based gas and a hydrogen gas are simultaneously introduced into the reaction vessel at a required pressure to pulverize the hydrogen-absorbing metal material and form a film mainly composed of metal fluoride on its surface. Is formed by vapor phase growth, and at least the surface or surface layer is highly activated against hydrogen molecules,
A method for highly activating and stabilizing a hydrogen-absorbing metal material, comprising deactivating a substance having surface poisoning other than hydrogen molecules. 2. A fluorine-containing gas and a hydrogen gas are further charged into a reaction vessel filled with the hydrogen storage metal material treated by the method for activating and stabilizing the hydrogen storage metal material according to claim 1.
At the same time, it is introduced under the required pressure and temperature conditions, and repeatedly occluding and releasing hydrogen with respect to the hydrogen-absorbing metal material, further advances the pulverization treatment of the hydrogen-absorbing metal material, and forms a metal on the surface or surface layer of the metal material. By forming a film containing fluoride as a main component, it is highly activated against hydrogen molecules, and deactivated against substances having surface poisoning other than hydrogen molecules. Activation and stabilization treatment method. 3. A hydrogen storage metal material in a reaction vessel which has been treated by the method for highly activating and stabilizing a hydrogen storage metal material according to claim 1 or 2 is converted into an inert gas at a temperature condition suitable for the metal material. Alternatively, heat treatment with hydrogen gas is performed to homogenize the film containing metal fluoride as a main component, thereby further activating hydrogen molecules and deactivating substances having surface poisoning other than hydrogen molecules. A method for highly activating and stabilizing a hydrogen storage metal material, characterized in that: 4. The hydrogen storage metal material according to claim 1 or 2 or 3, wherein the hydrogen storage metal material before filling in a reaction vessel in the method for highly activating and stabilizing a hydrogen storage metal material is a material such as a powder or an ingot. Alternatively, a method for highly activating and stabilizing a hydrogen storage metal material, which is one of a composite material, an intermediate product, and a finished product using the hydrogen storage metal as a matrix.