Study on the microstructure and electrochemical properties of Zr-Ti-Mn-Ni hydride alloy

Six kinds of Zr-based hydride alloy are designed. XRD analysis shows that the main phase of Zr1-xTix( NiCoMnV)2.1 alloy is Laves C15 when x is between 0 and 0.5, but the more the content of Ti, the more the Laves C14 phases increases. The amount of Laves C14 can be up to the amount of Laves C15 after substituted V and Fe by V-Fe alloy in Zr0.6Ti0.4 (NiCoMnVFeCr)1.7 alloy. The electrochemical measurements show that the discharge capacity of Zr0.9Ti0.1(NiCoMnV)2.1 electrode is about to 340 mAh/g, but with increase the amount of Ti, the discharge capacity of alloy electrode abruptly decreases. The discharge capacity of Zr0.6Ti0.4 (NiCoMn(V-Fe)Cr)1.62 alloy elecrode is about 200 mAh/g at the first cycle, the maximum capacity is more than that of the electrode with pure V, and about 315 mAh/g.