Elaboration and electrochemical characterization of LaZrCrNi-based metal hydride alloys.

Autor: Sahli, Ines, Ghodbane, Ouassim, Abdellaoui, Mohieddine
Zdroj: Ionics; Oct2016, Vol. 22 Issue 10, p1973-1983, 11p
Abstrakt: The elaboration of LaZrCrNi-based intermetallic compound was performed by mechanical alloying from LaNi and ZrCr precursors and characterized as active materials of negative electrodes in nickel-metal hydride (Ni-MH) batteries. The effect of the milling duration on the phase composition was investigated. The structural properties of the formed phases were determined by X-ray diffraction and quantified from the Rietveld refinement data. The increase of the milling time up to 40 h leads to the highest abundance of the LaZrCrNi phase, estimated at a weight content of 60.6 %, and a complete elimination of the LaNi intermetallic precursor. The chronopotentiometry, cyclic voltammetry, and chronoamperometry techniques were applied to characterize the electrochemical behavior of prepared LaZrCrNi-based compounds. The maximum discharge capacity was 152 mAh g, and a high electrochemical stability was obtained in the alkaline solution. The value of the hydrogen diffusion coefficient is equal to 2.1 × 10 cm s, reflecting an appropriate electrochemical hydrogenation kinetic in the LaZrCrNi-based compounds. [ABSTRACT FROM AUTHOR]
Databáze: Complementary Index