A study on ZrCrNiPtx alloys as negative electrode components for NiMH batteries

F.C. RUIZ; H A PERETTI; A, VISINTIN; W. E. TRIACA

INTERNATIONAL JOURNAL OF HYDROGEN ENERGY

PERGAMON-ELSEVIER SCIENCE LTD

Lugar: Miami; Año: 2011 vol. 36 p. 901 - 906

0360-3199

The effect of the addition of Pt on the electrochemical characteristics of AB2 type ZrCrNi alloys as negative electrode materials for nickel–metal-hydride (Ni-MH) batteries is studied. Electrochemical characteristics of the alloys as discharge capacity, activation behavior, high rate dischargeability (HRD) and electrochemical impedance spectroscopy (EIS) were analyzed. The resulting ZrCrNiPtx alloys (x = 0.05 and 0.1 corresponding to 5 wt. % and 10 wt. % respectively) retain the crystalline structure related to hexagonal C14 Laves phases, on both as-melted and annealed samples. The alloys containing Pt have a similar activation behavior than that of ZrCrNi alloy in as-melted alloy samples although this characteristic is improved in annealed samples with Pt. The discharge capacity of the ZrCrNiPtx alloys is higher than the discharge capacity corresponding to ZrCrNi alloys, except in the case of as-melted ZrCrNiPt0.1 alloy. The addition of Pt also improves significantly the high rate dischargeability, maintaining the capacity values in a wide range of discharge current .