| In this thesis, previous research work on V-based solid solution type hydrogen storage electrode alloys were exhaustively reviewed first. On this basis, by means of XRD, SEM, EDS, ICP analyses and electrochemical measurements, the phase structures and electrochemical properties at room temperature of V2.1TiNix (x=0.2-0.6) ternary alloys have been investigated systematically. Meanwhile, the influence of operating temperature on the electrochemical performance of V2.1TiNi0.4 alloy has been studied. Whereafter, the research scheme for improving the phase structures and electrochemical performance of V-based hydrogen storage electrode alloys by means of multi-component alloying and ball-milling was chosen and the method of step-by-step optimization was adopted.The study on the phase structures and electrochemical properties at room temperature of V2.1TiNix(x = 0.2, 0.3, 0.4, 0.5, 0.6) alloys shows that all alloys consist of a V-based solid solution main phase and a TiNi-based secondary phase with b.c.c. structure. The abundance and lattice parameters of the main phase decrease with the increase of nickel content, while the abundance of the secondary phase increases at the same time. The secondary phase forms a visible three-dimensional network along the grain boundaries of the main phase as x ≥ 0.4. The high-rate dischargeability and cycling stability of the alloys are noticeably improved with the increase of Ni content. However, the activation behavior and maximum discharge capacity decline as x increases from 0.4 to 0.6. Among the alloys studied, V2.1TiNi0.4 has a better overall electrochemical performance. This alloy can be activated in 2 cycles and has a discharge capacity of 457mAh/g at a discharge current of 25mA/g. Furthermore, this alloy shows a moderate capacity retention rate and high-rate dischargeability.The effects of operating temperature (T=25℃, 35 ℃, 45 ℃, 55 ℃) on the electrochemical performance of V2.1TiNi0.4 has been investigated systematically. It is found that as the temperature rises, the activation process becomes faster, the maximum discharge capacity is noticeably improved, but the cycling stability drops sharply. The exchange current density I_o and limiting current density I_L increase, while the impedance decreases, so the high-rate dischargeability is improved with the increase of the operating temperature. The measurements show that the increase of Ti element dissolve in the electrolyte at high temperature leads to a decline of cycling capacity.On the basis of the above work, the influence of multi-component alloying on the microstructure and electrode performance of V2.1TiNi0.4 has been investigated. The study on the phase structures and electrochemical properties of V2.1TiNi0.4Zrx (x= 0.03, 0.05, 0.07, 0.09) alloys shows that all of the alloys consist of a V-based solid solution main phase and a secondary phase. The alloy has a TiNi-based secondary phase as x≤0.03 and has a C14-type Laves secondary phase as x≥0.05. At the same time, the lattice parameters of the main phase and secondary phase increase with the increase of Zr content. Amongthe alloys studied, V2.1TiNi0.4Zr0.07 has the highest discharge capacity of 489mAh/g and the highest capacity retention rate. However, V2.1TiNio.4Zro.o3 had a perfect high-rate dischargeability. Furthermore, the study on the phase structures and electrochemical properties of (V2.1TiNi0.4 + x wt.% AB5) multi-component alloys (x=10, 30, 50, 70, 90) shows that the alloys consist of a V-based solid solution phase and a CaCus-type LaNi5-based phase. As x increases, LaNi5 phase enriches and becomes the main phase, while V-based solid solution phase decrease and becomes the secondary phase. As x≥30, a La2Ni3 phase appears in the alloys. With the increase of x from 10 to 50, the activation number of the alloy increases from 2 cycles to 7 cycles. Hereafter, the activation number decreases as x increases. At the same time, with the increase of x from 10 to 90, the maximum discharge capacity drops gradually from 423 mAh/g to 314 mAh/g, and the capacity reten...
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