Preparation of AB_5 Polyhydric Hydrogen Storage Alloy by Polymer Network Gel Method

Preparation of AB5 Polyhydric Hydrogen Storage Alloys by Polymer Network Gel Method ZHANG Jing-Jin, WANG Peng, CHEN Wen-Xin, YI Shou-Jun, LIU Ying-Liang (Department of Chemistry, Jinan University, Guangzhou 510632, China) The precursor was mixed with excess CaH2, and the reduction diffusion reaction was used in 900. The multi-dimensional hydrogen storage alloy IaCen was prepared at -1000°C. XRD and SEM analysis showed that the structure of the alloy is similar to that of LaNis and is CaCus type. The particle size is about 2-3m, and the distribution is uniform and spherical.

In 1968, the Dutch reported that LaNis alloy has a high hydrogen storage capacity, and after that, the research and utilization of hydrogen storage alloys have been greatly developed. In 1984, the Philips company of the Netherlands solved the problem of capacity decay of the hydrogen storage material LaNis during charge and discharge, caused excessive expansion and contraction of the MH cell, and the large volume change rate before and after hydrogen absorption and release resulted in severe powdering of the alloy. In order to overcome these shortcomings, people use the method of adding auxiliary elements in place of basic elements. The substitutional elements on the A side mainly include Nd and Ce. Studies have shown that changing the content and proportion of substituted elements properly, adjusting the equilibrium hydrogen pressure of the alloy hydride to obtain a high electrochemical capacity of the alloy 1. In Mm (NiCoMnAl) 5 hydrogen storage alloy electrode material Mm = Lao.4Ceo. In the case of Ndo2Pro.3, the maximum discharge capacity is 290mAh/gt2*3. For the substitute elements Co, Mn, Al, etc. on the B side, some comprehensive studies have proved that the ratio of each element is better than that of Coo.75Mno.4Alo3. 4. . The alloy structure is similar to LaNi5 and is of the CaCu5 type. It is a scanning electron micrograph of the alloy. The photograph shows that the particle size is about 2 to 3, and the distribution is uniform and spherical.

Scanning electron microscopy (SEM) photographs of the alloy's XRD pattern alloys Thus, using the above method, without any mechanical milling, a multicomponent alloy with pure phase, small product size, and uniform distribution can be obtained while ensuring the integrity of the grain structure of the material.

A multiphase hydrogen-absorbing alloy Laa4Cea1NA.2Pr0.3Ni3.55Co.75Mn.4AI0.3. with a particle size of about 2 to 3 Mm was prepared using a polymer network-reduction-diffusion method. The particles were uniformly distributed and spherical. Compared with the traditional smelting method using high-purity metal, this experiment uses metal salts as the starting material. For the preparation of multi-element alloys, it is easier to adjust the composition of each metal, and the reaction temperature is reduced and the reaction time is shortened.

Jiang Jianjun, Lei Yongquan, Sun Dalin et al. Effect of Rare Earth Composition on Electrochemical Properties of Re (NiCoMnTi) Hydrogen Storage Alloys. Acta Metallurgica Sinica, 199531(8):379-383. Zhang Jingyi et al.: Preparation of AB5 Type Multi-element Hydrogen Storage Alloy by Polymer Network Gel Method