AB 5-type hydrogen storage alloy used as anodic materials in borohydride fuel cell

Abstract

Fuel cells using borohydride as the fuel have received much attention because of the high potential and power density. In this work, AB 5-type hydrogen storage alloy used as the anodic material instead of the noble metal in a borohydride fuel cell (BFC) has been investigated. LmNi 4.78Mn 0.22 (where Lm is La-richened mischmetal) alloy shows high electrochemical catalytic activity in both the discharge process and the hydrogen generation process. The generation rate of hydrogen increases with increasing discharge current density. The utilization of the fuel (KBH 4–KOH solution) also increases with increasing discharge current density. It suggests that high-rate discharging is useful to improve the utilization of the fuel. In order to use the AB 5-type hydrogen storage alloy in a borohydride fuel cell, it is necessary to improve the utilization of the fuel further.