Hydrogen storage properties of Ti1 + xCr2−yMny alloys

Fundamental studies were performed with the aim of developing hydrides of titanium-based alloys with suitable properties for hydrogen and energy storage applications. We investigated the hydrogen absorption-desorption characteristics of the alloy Ti1 + xCr2−yMny (0.1 ⩽ x ⩽ 0.3; 0 ⩽ y ⩽ 1). The rate of the initial activation process increased as x was increased, but the reversible hydrogen storage capacity decreased. Ti1 + xCr2−yMny reacted readily with hydrogen to form hydrides at a hydrogen pressure of 40 atm and −20 °C. The reversible hydrogen storage capacity of Ti1.2Cr2−yMny decreased with decreasing manganese content while the plateau pressure increased. The hysteresis in the absorption-desorption isotherms decreased markedly for titanium concentrations in the range 0.2 ⩽ x ⩽ 0.3 and for manganese concentrations in the range 0.5 ⩽ y ⩽ 0.8.