38results about How to "Fast hydrogen absorption and desorption rate" patented technology

A holding hydrogen alloy used for making metallic hydride air conditioning. The chemical formula is La0.6Nd0.4Ni4.8Mn0.2Cux(x=0.1-0.4). Release hydrogen dosage of it is 1.43wt% at common temperature. Decomposition pressure at 18 DEG C is between 1amp and 1.5amp. Hysteresis coefficient is 0.09-0.24. Rate of grade of parallel line is 0.05-0.1. Absorbing hydrogen dosage can reach 90% in 50-80s. Meanwhile, Releasing and absorbing hydrogen dosage dynamic property is improved.

The invention discloses a magnesium hydride (MgH2) and ferrum-containing sulfide composite hydrogen storage material and a preparation method thereof. The composite hydrogen storage material comprises MgH2 and 10-30 wt% of ferrum-containing sulfide, wherein the ferrum-containing sulfide is Fe3S4 or FeS or FeS2. The method comprises the following steps of: adding the ferrum-containing sulfide which serves as an additive into MgH2, and carrying out ball milling at the pressure of 0.1-0.5MPa in the atmosphere of high-purity argon to prepare the composite hydrogen storage material. The hydrogen absorption and desorption rate of the MgH2 and ferrum-containing sulfide composite hydrogen storage material is over 2 times higher that that of the MgH2 hydrogen storage material which contains no ferrum-containing sulfide. The MgH2 and ferrum-containing sulfide composite hydrogen storage material is simple in preparation process, has stable performances and can be used for storing hydrogen in the field of fuel cells.

The invention provides a method for improving a hydrogen storage property of lithium borohydride, and belongs to the technical field of hydrogen storage materials. The method comprises the following steps of: mixing the lithium borohydride and alkaline-earth metal alanate according to the molar ratio of 2:1-10:1 under the protection of vacuum or inert gases, and heating mixed powder of the lithium borohydride and the alkaline-earth metal alanate to a certain temperature to ensure that the alkaline-earth metal alanate is decomposed into alkaline-earth metal hydride, aluminum or aluminum alloy in advance. By the method, double effects of in situ and concerted catalysis in the process of discharging and absorbing hydrogen of the lithium borohydride by using the alkaline-earth metal alanate are achieved, so that a hydrogen discharging temperature of the lithium borohydride is greatly reduced, and the hydrogen absorbing and discharging dynamic properties of the lithium borohydride are improved. The method is suitable for storing the hydrogen safely and efficiently and is particularly applied in fields of hydrogen fuel cells and the like.

The invention discloses lithium-sodium dual-alkali metal aluminum-hydrogen compound and a synthesis method thereof. The lithium-sodium dual-alkali metal aluminum-hydrogen compound has a single cubic structure and has the chemical formula of LixNa3-xAlH6, wherein x is 0.9-1.3. The lithium-sodium dual-alkali metal aluminum-hydrogen compound has high proportion hydrogen storage capacity and fast hydrogen absorption rate. The preparation method for the lithium-sodium dual-alkali metal aluminum-hydrogen compound comprises the following steps: mixing Li3AlH6 and Na3AlH6 according to the molar ratio of 0.9:2.1-1.3:1.7, and ball-milling for 10-30 h at a speed of 400 rpm-500 rpm, to obtain LixNa3-xAlH6, wherein x is 0.9-1.3; Li toms and Na atoms in the structure occupy gaps of an AlH6 octahedron, and the Li toms and the Na atoms are replaced with each other along with the different ratio of the Li toms and the Na atoms. The method is simple and easy to implement, and is suitable for mass commercial production; the optimum proportion hydrogen storage capacity is high, the initial dehydrogenation temperature is low, and the hydrogen absorption rate is obviously improved.

The invention relates to a low vanadium hydrogen storage alloy and its preparation method and use. The element composition of the low vanadium hydrogen storage alloy is: (TiV a ) x (CrMo b ) y M 1‑x‑y ; Among them, M is one or a combination of at least two of Zr, Fe, Mn or Ce, x=0.4-0.5, y=0.5-0.6, a=0.05-0.15, b=0.05-0.15. The preparation method includes the following steps: (1) batching according to the formula, and then smelting to obtain an intermediate material; (2) sequentially subjecting the intermediate material obtained in step (1) to vacuum casting and heat treatment to obtain the hydrogen storage alloy . The low vanadium hydrogen storage alloy provided by the present invention, through the optimized design of each component, phase control and process optimization, significantly increases the effective hydrogen release amount, has good cycle performance, high activity and high crystallinity, and has a simple preparation process. The preparation cost is low.

The invention relates to a preparation method of an in-situ growth nano magnesium hydride loaded high specific surface material. An alkali metal hydride, magnesium halide and a support material are utilized for in situ synthesis of the material under a ball milling condition. The invention has the technical effects that: magnesium hydride is generated in situ on the support material surface through replacement reaction, the nano-composite hydrogen storage material with low operating temperature and fast hydrogen absorption and desorption rate is prepared under a mild condition, the problems of harsh preparation conditions, large product particle size and the like in previous nano magnesium hydride preparation, and the thermodynamic and dynamic performance of the magnesium hydride hydrogen storage material can be improved.

The invention discloses a magnesium metal hydride phosphate complex hydrogen storage composite material and a preparation method. The hydrogen storage composite material consists of MgH2 powder and a phosphate complex, wherein the content of the phosphate complex is 15-35% of the mass of the composite material, and the phosphate complex is one of LiFePO4 and LiCoPO4. The preparation method of the hydrogen storage composite material comprises the steps of putting the MgH2 powder and phosphate complex into a ball milling tank under the protection of argon atmosphere; performing intermittent ball milling treatment under 0.1-0.5MPa high-purity argon to obtain the hydrogen storage composite material. The hydrogen absorption / desorption speed of the hydrogen storage composite material disclosed by the invention is improved to over three times as compared with the MgH2 without phosphate; meanwhile, the preparation process is simple, the energy consumption is little, the preparation cost is low, and industrialization and popularization are easy to realize.

The invention relates to a nanometer catalysis composite nitride hydrogen storage material and a preparation method thereof; the nanometer catalysis composite nitride hydrogen storage material is characterized in that a precursor is decomposed in a nitride substrate to precipitate nanometer catalysis phase with high activity, so as to realize quick reversible hydrogen absorption and desorption; more particularly, the nitride hydrogen storage material is the nitride composite material system of alloying magnesium powders and LiNH2 nanometer phase which has catalysis effect is uniformly arranged in the LiNH2 substrate; the alloying magnesium powders is a multiple catalysis material system which is formed by Mg powder and transition elements such as Cr, Mn, Ti, Fe, Cu, Ni and Y or other mixtures. The preparation method is characterized in that the nitride hydrogen storage material with high hydrogen absorption and desorption rate is gained by a two-step method: high-pressure hydrogen atmoesphere reaction ball-grinding alloying and inertia gas protection ball-grinding compounding. The composite nitride hydrogen storage material with high hydrogen absorption and desorption rate can be gained by the preparation method of the invention.