Performance of LaNi/sub 4.7/Sn/sub 0.3/ metal hydride electrodes in sealed cells

Cycle life and kinetics studies were performed on sealed nickel metal hydride electrochemical cells with anodes of LaNi/sub 4.7/Sn/sub 0.3/ and of a standard mischmetal alloy. The modest increase in cell capacity of the LaNi/sub 4.7/Sn/sub 0.3/ alloy at higher rates of discharge suggests improved kinetics. AC impedance studies as a function of cycle life indicate the onset of cell failure. Self-discharge rates in sealed cells correlate with alloy plateau pressures measured by gas phase isotherms and internal cell pressures. Cycle life of the LaNi/sub 4.7/Sn/sub 0.3/ was inferior to cells of standard mischmetal formulation Mm(NiAlCoMn)/sub 5/.