This disclosure provides a hydrogen storing alloy and a production method thereof. The hydrogen storing alloy has a chemical composition of a general formula R.sub.(1-x)Mg.sub.xNi.sub.y, wherein R is one or more elements selected from rare earth elements comprising Y, x satisfies 0.05≦x≦0.3, and y satisfies 2.8≦y≦3.8. The ratio of the maximal peak intensity present in a range of 2θ=31°-33° to the maximal peak intensity present in a range of 2θ=41°-44° is 0.1 or less (including 0), as measured by X-ray diffraction in which a Cu-Kα ray is set as an X-ray source.

A solid-state hydrogen storage device includes a first storage for storing a reversible solid-state hydrogen storage material, a reactor disposed in the first storage to enable a hydrolysis reaction of a non-reversible solid-state hydrogen storage material to be performed therein, and a fuel cell stack, wherein the non-reversible solid-state hydrogen storage material is stored in the reactor, and wherein the non-reversible solid-state hydrogen storage material releases heat when the hydrolysis is performed.

A heating/cooling system for furnishing employs an electrochemical heat transfer device. An electrochemical heat transfer device may be an electrochemical hydrogen compressor that pumps hydrogen into and out of a tank having a metal hydride forming alloy therein. The absorption of hydrogen by the metal hydride forming alloy is exothermic, produces heat, and the desorption of the hydrogen from the metal hydride forming alloy is endothermic and draws heat in. An electrochemical hydrogen compressor may be configured between to tanks and pump hydrogen back and forth to form a heat transfer device. A heat exchange device may be coupled with the tank or may comprise the outer surface of the tank to transfer heat to an object or to the surroundings. A closed loop may be configured having two tanks and one or two electrochemical hydrogen compressors to pump the hydrogen in a loop around the system.

The present disclosure relates to improved processes for the preparation of metal hydrides. The present disclosure also relates to metal hydrides, e.g., metal hydrides prepared by the processes described herein, that exhibit enhanced hydrogen storage capacity when used as hydrogen storage systems.

Provided are a novel heat utilization system and heat generating device that utilize an inexpensive, clean, and safe heat energy source. A heat utilization system 10 includes a heat-generating element 14 configured to generate heat by occluding and discharging hydrogen, a sealed container 15 having a first chamber 21 and a second chamber 22 partitioned by the heat-generating element 14, and a temperature adjustment unit 16 configured to adjust a temperature of the heat-generating element 14. The first chamber 21 and the second chamber 22 have different hydrogen pressures. The heat-generating element 14 includes a support element 61 made of at least one of a porous body, a hydrogen permeable film, and a proton conductor, and a multilayer film 62 supported by the support element 61. The multilayer film 62 has a first layer 71 made of a hydrogen storage metal or a hydrogen storage alloy and having a thickness of less than 1000 nm and a second layer 72 made of a hydrogen a hydrogen storage metal different from that of the first layer, a hydrogen storage alloy different from that of the first layer, or ceramics and having a thickness of less than 1000 nm.

A method for producing a thin film according to the present disclosure comprises a step of forming the thin film on a substrate using a target. The target is formed of a mixture containing a first material and a second material. The first material has a composition represented by ATiO.sub.3 (where A is at least one selected from the group consisting of Ba and Sr). The second material has a composition represented by EH.sub.2 (where E is at least one selected from the group consisting of Ti and Zr). The thin film is formed of a first oxide containing A, Ti, and O. Some of oxide ions contained in the first oxide have been replaced by hydride ions.

A method for preparing a magnesium-based hydrogen storage material, includes: a Mg—Ce—Ni family amorphous alloy is prepared by a rapid cooling process; the amorphous alloy is pulverized, so as to obtain a amorphous powder; the amorphous alloy is activated, so as to obtain a MgH.sub.2—Mg.sub.2NiH.sub.4—CeH.sub.2.73 family nanocrystalline composite; the abovementioned composite is carried out a hydrogen absorption and desorption cycle, then the composite is placed in a pure Ar atmosphere for passivation, finally, the passivated composite is oxidized, so as to obtain a MgH.sub.2—Mg.sub.2NiH.sub.4—CeH.sub.2.73—CeO.sub.2 family nanocrystalline composite.

Laves phase-related BCC metal hydride alloys historically have limited electrochemical capabilities. Provided are processes of activating these alloys to produce hydrogen storage materials with greater than 200 mAh/g capacities and commonly much greater than 300 mAh/g capacities. The processes include cooling the alloy during hydrogenation to reduced temperatures or by subjecting the materials to significantly increased hydrogen pressures. Temperatures in many embodiments do not exceed 300° C. By decreasing the temperature or increasing the hydrogen pressure the phase structure of the material is optimized to increase a synergistic effect between multiple phases in the resulting alloy thereby greatly improving the electrochemical capacities.

A catalyst used for dehydrogenation of an organic hydrogen-storage material to generate hydrogen, a support for the catalyst, and a preparation process thereof are presented. A hydrogen-storage alloy and a preparation process thereof are also provided. A process for providing high-purity hydrogen, a high-efficiently distributed process for producing high-purity and high-pressure hydrogen, a system for providing high-purity and high-pressure hydrogen, a mobile hydrogen supply system, and a distributed hydrogen supply apparatus are also described.

A solid state hydrogen storage device includes: a solid state hydrogen storage material in which hydrogen is stored; a heat exchanger in a plate shape that is inserted into the solid state hydrogen storage material and exchanges heat with the solid state hydrogen storage material through contact with the solid state hydrogen storage material; a storage container in which the solid state hydrogen storage material and the heat exchanger are accommodated; and a cap connected to an upper portion of the storage container and configured to seal the interior of the storage container.