Autori: Dan Lupu, Alexandru Radu Biriş, Emil Indrea, Alexandru Sorin Biriş, Gabriela Bele, Louis Schlapbach, Andreas Züttel
Editorial: ELSEVIER, Journal of Alloys and Compounds, 291 (1), p.289 - 294, 1999.
The substitution of chromium for vanadium in ZrV1.5-x Cr x Ni 1.5 leads to a cubic C15 phase as the main phase with a low content of the secondary phase Zr7Ni10. The lattice parameters suggest a complex redistribution of V, Ni or Cr between the B and A sites of the Laves phase AB2, which does not depend only on the Cr content. The pressure-composition isotherms show sloping plateaux, alloy hydrogen contents between 3.35 and 4.25 H/mol and desorption enthalpies of ΔH=41.8-50.2 kJ/mol H2 at constant H concentration (1.8 H/mol). Discharge capacities of between 113 and 222 mAh/g have been obtained for the hydride electrodes at a 160 mA/g discharge current; for the Cr-substituted alloys the discharge capacities increase with x.
Cuvinte cheie: Laves phase AB2 , pressure-composition isotherms , X-ray diffraction