Cyclic stability and high rate discharge performance of (La,Mg)_5Ni_(19) multiphase alloy

摘要

The cyclic stability and high rate discharge performance of (La,Mg)_sNi_(19) multiphase alloy were investigated in this work. The results show that the alloy is composed of Pr_5Co_(19)-type (2H), Ce_5Co_(19)-type (3R), CaCu_5-type and Ce_2Ni_7-type phase after annealing at 1123 K. The total phase abundance of Pr_sCo_(19)-type (2H) and Ce_5Co_(19)-type (3R) is 63.3%. That composition decides the good cyclic stability both in repeated hydriding/dehydriding and charging/ discharging process for this alloy. Moreover, the alloy shows the higher high rate discharge capacity at room temperature and it remains 140 mA h/g at the current density of 3600 mA/g.