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

The invention discloses a novel Mg-In-Ag ternary hydrogen storage alloy system and a preparation method thereof, belonging to the technical field of hydrogen storage materials. The composition of the hydrogen storage material is as follows: the atomic percentage of (Mg+In) is 80-85%, wherein the proportion of In in (Mg+In) is 3-6%, and the rest is Ag. Weigh the Mg block and Ag sheet according to the alloy composition, use the induction melting furnace to melt the Mg-Ag binary low-melting point alloy first, then weigh the In block according to the proportion and melt it together with the above binary alloy to obtain the Mg-In-Ag ternary alloy The alloy is ground into alloy powder after removing the surface oxide skin, and then put into a ball mill jar filled with hydrogen to prepare a highly active powder hydrogen storage material by mechanochemistry, which can be directly used as the final hydrogen storage material product. The hydrogen storage material of the invention has the characteristics of no need for hydrogen absorption and desorption activation, high hydrogen storage capacity, low hydrogen absorption and desorption temperature, and fast hydrogen absorption and desorption rate.

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 discloses a hydrogen storage alloy suitable for low-pressure solid-state hydrogen storage and a preparation method thereof. The hydrogen storage alloy can be composed of R 1‑x‑y m x Mg y (Ni 1‑b T b ) a The general chemical formula shows that, in the formula, x , y , a , b Indicates the molar ratio, 0≤ x ≤0.35, 0.15≤ y ≤0.30, 2.90≤ a ≤4.10, and b The value satisfies 0≤a b ≤0.20; the present invention also provides a preparation method of the above alloy, which prepares a hydrogen storage alloy through batching, smelting and heat treatment. The preparation method is simple and can effectively eliminate AB in the alloy. 5 Phase and AB 2 The phase non-superlattice structure ensures the purity of the superlattice phase structure and the hydrogen storage performance of the obtained alloy. The hydrogen storage alloy prepared has a reversible hydrogen absorption and desorption capacity greater than 1.6wt% at 25~100°C, within 5 minutes That is to absorb and release hydrogen to more than 80% of the maximum capacity, and the hydrogen release platform pressure is greater than 1MPa.

The invention discloses an MgH2-BiVO4 hydrogen storage composite material which consists of MgH2 and BiVO4, wherein the content of the BiVO4 accounts for 10-40% of the total mass of the composite material. A preparation method of the hydrogen storage composite material comprises the following steps: in a glove box protected by argon, putting the MgH2 powder and the BiVO4 in a ball milling tank, and performing ball milling in the presence of 0.1-0.5MPa argon at a ball-material mass ratio of (15-35):1 and the revolving speed of 450-550r / min for 1-3 hours, wherein 15-25 minutes of intermittence is spaced between every two times of 20-45 minutes of ball milling; after the ball milling, naturally cooling to the room temperature so as to obtain the MgH2-BiVO4 hydrogen storage composite material. Under relatively low temperature, compared with the MgH2 without the addition of BiVO4, the hydrogen absorption rate and maximum hydrogen absorption amount of the hydrogen storage composite material are improved by more than one time; at the same time, the preparation method is simple, the preparation cost is low and the hydrogen storage composite material is suitable for industrialization-scale preparation.

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 discloses a hydrogen purifying device with a herringbone structure, which comprises a reaction vessel connected with the inlet and exhaust pipes, and the inner chamber of the reaction vessel is provided with a herringbone structure connected with the inlet and exhaust pipes. Hydrogen pipelines are arranged in a shape, and the inner cavity of the reaction vessel is also provided with heat sinks arranged in a herringbone shape, and the hydrogen pipelines and heat sinks are arranged alternately. The invention adopts the hydrogen diffusion pipeline of the fishbone structure and the corresponding heat exchange inner wall, which greatly improves the heat exchange effect during hydrogen absorption and desorption, and significantly improves the hydrogen absorption and desorption rate of the hydrogen storage alloy. The hydrogen of the fishbone structure The pipeline and the inner wall can disperse the stress generated when the hydrogen storage alloy absorbs and releases hydrogen, enhance the pressure bearing strength of the device, and also prevent the hydrogen storage alloy powder from accumulating at the bottom of the device after a long period of use. Therefore, the device can greatly improve the purification efficiency of hydrogen in actual use, and it is also more guaranteed in terms of service life and safety.

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.