快速凝固钛钒系贮氢合金电化学性能研究

Study on Electrochemical Properties of Rapid Solidified TiV-Based Hydrogen Storage Alloy

研究了快速凝固处理对钛钒系贮氢电极合金Ti0.8Zr0.2V2.4Mn0.48Cr0.72Ni0.9的相结构、特别是电化学性能的影响规律。XRD研究表明:合金主要由六方结构的C14 Laves相和体心立方结构的钒基固溶体相所组成,快速凝固减少了合金中C14 Laves相的含量。电化学性能分析表明:快速凝固降低了合金电极的最大放电容量,增加了电极的活化次数,提高了电极表面的反应阻抗,恶化了电极的动力学性能,但是却大大改善了合金电极的循环稳定性。

The phase structures and the electrochemical properties of the TiV-based hydrogen storage electrode alloy Ti0.8Zr0.2V2.4 Mn0.48Cr0.72Ni0.9 after rapid solidification have been studied. It is found by XRD analysis that the alloy mainly consists of C14 Laves phase with hexagonal structure and V-based solid solution phase with BCC structure. The rapid solidification leads to the decrease in content of the C14 Laves phase in the alloy. Electrochemical analyses show that the rapid solidification reduces the maximum discharge capacity, increases the activation cycles, elevates the surface reaction resistance and worsens the kinetic properties of the alloy electrode. However, the cyclic stability of the alloy electrode is improved greatly after rapid solidification.