Kinetics of Hydrogen Absorption in Hydrogen storage alloy

摘要

Hydrogenation kinetics of Ml-Ni-Co-Mn-Al and Ml-Ni-Co-Mn-Al-Cu alloy in α+β phase at the temperature range of 30-70°C has been studied . The kinetic mechanism of hydrogen absorption is not affected by initial hydrogen pressure. Temperature does not influnce the rate of hydrogen absorption obviously. In the prior and later period of hydrogen absorption the rate-controlling step is chemical reaction and hydrogen diffusion in the hydride phase respectively for Ml-Ni-Co-Mn-Al alloy. Adding Cu, the rate-controlling step changes from chemical reaction to the nucleation and growth of β phase in the prior period and the process of hydrogen absorption still contrlled by diffusion in the later period.