| In this paper, prescription and process technology of dynamical type hydrogen storage alloy were investigated. By studying the effects on the electrical performance from different aspects, such as compared composition, stoichiometry, heat treatment technology and power technology, optimized prescription and process technology with low-cost, but generally meeting the basic technical indexes of the dynamical type alloy, were obtained. Meanwhile, thermal electrochemistry, a new method to be used to assess the performance of dynamical type hydrogen storage alloy material, was proposed for the first time. Main studying results are as follows:After studying the effects on the electrochemical performance of RE(NiCoMnAl)5 by changing the proportion of the rare earth La, Ce, Pr and Nd, it is found that, when the composition of the rare earth are La60 Ce20Pr5Nd15, La55Ce20Pr5Nd20 and La55Ce25Pr5Nd15, this kind of hydrogen storage alloy can meet five conditions at the same time, that is, the discharge capacity under 0.2C>300 mAh g-1, high rate discharge performance value (HRD)>0.70, activated number under 0.2C<5 times, cycle life under 3C >400times and discharge efficiency at lower temperature(-18C, 1C)>88%. By predicting of BP nerve net program self-made, whose comprehensive performances were pictured, discharge capacity under 0.2C and 5C higher than 320 mAh g-1, 230 mAh g-1 respectively, and HRD higher than 0.70, etc. Optimized proportional band of rare earth was also found.Electrochemical, thermodynamic and kinetic performances of series alloys MlNi3.6+xCo0.7Mn0.4Al0.3 (X=-0.2, -0.1, 0.0, 0.1, 0.2) were studied, and it is found that, phase structure of the alloy doesn't change with the stoichiometry coefficient. There is only one principle phase, CaCu5 hexagonal crystal structure. When X value is 0.1, c/a value reaches the maximum. Discharge capacity under 0.2C, 1C, 5C, high rate discharge value and cycle life under 3C, are 320 mAh g-1, 300 mAh g-1, 260 mAh g-1 0.81 and 530 times respectively. When X value are -0.2, -0.1, 0.0, 0.1and 0.2 separately, the activated number under 0.2C are 3, 4, 7, 5and 6 times respectively, furthermore, with the increase of X, discharge efficiency of the electrode at high temperature (45C, 1C) and room temperature (25C, 1C) go down, but goes up at low temperature (-18 C, 1C) . As to the non-stoichimetric alloys, greatly less or super stoichiometric, the enthalpy variation of absorbing hydrogen reaction are more minus, but to AB5 or AB5.1, both the enthalpy variation and entropy variation get close to that of LaNi5.Effects on the microstructure, thermodynamic and electrochemical performances of Ml(NiCoMnAl)5.1 treated with different heat treatment processes were studied. The results show that, compared with casting alloy, the hydrogen storage alloy, after two stage heat treatment(1000C -850C), has obviously stronger diffraction peak, but with half-height width of main peak descending from 0.36 to 0.20, and also has a great change in lattice parameters, a value getting larger, c value and cell volume V becoming smaller, expanding ratio of absorbing hydrogen going down obviously. Compared with casting alloy electrode, discharge capacity under 0.2C, 1C, 5C, activated number and cycle life under 3C are up to 323 mAh g-1, 301 mAh g-1, 268 mAh g-1, 3 and 450 times from 311 mAh g-1, 288 mAh g-1, 214 mAh g-1, 8 and 333 times respectively. Discharge efficiency at -18C increases to 94.8% from 73.5%, but decreases nearly 3% at 45 C, while the platform pressure and enthalpy variation of absorbing hydrogen all become smaller, and the gradient degree of absorbing hydrogen platform getting smaller from 0.0036 to 0.0026.Tested by SEM, circulate volt-ampere, polarization curve and electrochemistry impedance, the electrode performance of hydrogen storage alloy powder prepared by three ways, dry method, wet method, and wet method with additives, were analysed. Results show that: the Oxygen content of alloy obtained by three ways are: 726ppm, 1350ppm and 831ppm separately. Powder in dry way, appear near sp...
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