Effects of Cu Substitution for Sn on the Electrochemical Performance of La0.7Mg0.3Al0.3Mn0.4Sn0.5−xCuxNi3.8 (x = 0–0.5) Alloys for Ni-MH Batteries

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).