Metal-hydride electrodes made of an AB2 alloy of the composition Zr0¨5Ti0¨5V0¨6Cr0¨2Ni1¨2 are studied for AC impedance behaviour at several of their state-of-charge values. Impedance data at any state-of-chargecomprisetwoRC-time constants and accordingly are analysed by using a nonlinear-least-square-fitting procedure. Resistance of the electrode and frequency maximumf* of the lowfrequency semicircle are found useful for predicting state-of-charge of the metalhydride electrodes.
