High-entropy alloys as anode materials of nickel - metal hydride batteries

High-entropy alloys are potential candidates for various applications including hydrogen storage in the hydride form and energy storage in batteries. This study employs HEAs as new anode materials for nickel - metal hydride (Ni-MH) batteries. The TixZr2-xCrMnFeNi alloys with different Ti/Zr ratios, having the C14 Laves structure, are used. These alloys are selected because they show room-temperature hydriding/dehydriding capability. The HEAs successfully act as negative electrode of Ni-MH batteries with good charge/discharge cyclability, while there are optimum Ti/Zr ratios for the highest storage capacity and the fastest activity. These findings introduce HEAs as potential anode materials for Ni-MH battery application.