The effect of temperature on the electrode properties of the directly prepared Ti3Ni2 alloy

Xu, YH Chen, CP Wang, QD Chen, LX

Yh. Xu et al., The effect of temperature on the electrode properties of the directly prepared Ti3Ni2 alloy, INT J HYD E, 26(11), 2001, pp. 1177-1181

21

INGLESE

Article

Environmental Engineering & Energy

INTERNATIONAL JOURNAL OF HYDROGEN ENERGY

0360-3199 → ACNP

26

11

2001

1177 - 1181

ISI

0360-3199(200111)26:11<1177:TEOTOT>2.0.ZU;2-M

The electrochemical properties of a new hydrogen storage alloy Ti3Ni2 have been studied in detail. The results show that the discharge capacity of Ti3 Ni2 alloy reaches 384.4 mA h/g (corresponding to Ti3Ni2H3.7) at 353 K and 1 45.5 mA h/g (corresponding to Ti3Ni2H1.47) at 278 K. At the higher temperat ure (353 K), two plateaus appear on the discharge curve, and at the lower t emperature (278 K) only one plateau. The kinetic property of Ti3Ni2 alloy e lectrode is poor, The following properties, namely the retention of charge, the activation of alloy, the kinetic property of Ti3Ni2 alloy (including t he exchange current, the diffusion coefficient of hydrogen and high-rate di schargeability) can all be improved by increasing the temperature. It can b e seen from X-ray diffraction analysis that two phases exist in alloy: name ly the cubic Ti2NiH phase with Fe3W3C structure and the cubic TiNiH phase f or the alloy cycled in alkaline solution, and the cubic Ti2NiH0.5 phase wit h Fe3W3C structure and the cubic TiNiH phase for the alloy hydrogenated wit h gaseous hydrogen. (C) 2001 International Association for Hydrogen Energy. Published by Elsevier Science Ltd. All rights reserved.