Effects of Cu substitution for Sn on the electrochemical performance of Lasub(0.7)Mgsub(0.3)Mnsub(0.4)Snsub(0.5-x)Cusub(x)Nisub(3.8)(x=0-05) alloys for Ni-MH batteries

Abstract

The effects of substitution of Cu for Sn on the electrochemical discharge capacity performance of La0.7Mg0.3Al0.3Mn0.4Sn0.5−xCuxNi3.8 (x = 0.0, 0.1, 0.2, 0.3, and 0.5) negative electrode alloys were investigated. Results indicate that increasing Cu content enhanced electrochemical behavior by increasing the maximum discharge capacity from 239.8 mA·h/g (x = 0) to 305.2 mA·h/g (x = 0.5), the discharge capacity retention at the 100th cycle from 78.0% (x = 0) to 81.8% (x = 0.5), and the high rate dischargeability (HRD) from 25.7% (x = 0) to 80.6% (x = 0.5).