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The crystal structure, activation performance. hydrogen storage properties. thermodynamics, pulverization resistance and absorption/desorption kinetics of LaNi(13.8)Al(10)M(0.2) (M = Ni, Cu, Fe, Al, Cr, Mn) hydrogen storage alloys were investigated systemically The absorption/desorption pressure-composition (PC) isotherms and kinetics were measured at a temperature range of 413-493 K by the volumetric method It was found that all the investigated alloys showed CaCu(5) type of hexagonal structures and the partial substitution of M for Ni resulted in the increase of the unitcell volumes in an orderof Ni < Cu < Fe < Al < Cr < Mn The activation became easier with Cr substitution for partial Ni but a little harder for the Cu, Fe, Mn, Al contained alloys M elements decreased the absorption/desorption plateau pressure in an order of LaNi(4)Al > LaNi(3.8)Al(10)Cu(0.2) > LaNi(3.8)Al(10)Fe(0.2) > LaNi(3.8)Al(10)CrO(2) > LaNi(3.8)Al(10)Mn(0.2) > . There were linear relationships between plateau pressure and cell volume of tile investigated alloys The absolute values of the enthalpy for all the alloys were increased with M substituteJ for partial Ni. Al and Cu improved the pulverization resistance. The absorption kinetics was very fast while the necessary times taken by LaNi(3.8)Al(1.0)M(0.2) alloys to desorb 90% of their maximum hydrogen capacity were increased in an order of Ni < Cu < Fe < Al < Cr < Mn. (C) 2009 Elsevier B V All rights reserved