Lithium transport through Li1-delta Mn2O4 electrode involving the orderingof lithium ion by numerical analysis of current transient

Lithium transport through Li1-deltaMn2O4 electrode during the lithium inter calation involving the disorder to order phase transition was investigated by numerical analysis of the current transient. All the measured current tr ansients showed non-Cottrell behaviour during the whole lithium intercalati on, and the relationship between the initial current level and the applied potential drop followed Ohm's law. The current transient was numerically si mulated based upon the 'cell-impedance controlled' lithium transport at var ious applied potential steps. The current transient theoretically calculate d well coincided with that transient experimentally measured in value and s hape. The typical current transient showed two 'quasi-current plateaux' sep arated by a steep current drop in value, indicating the coexistence of the disordered and ordered phases, as confirmed from the concentration profile across the electrode. From the experimental and theoretical results, it was strongly inferred that lithium transport through the Li1-deltaMn2O4 electr ode is governed by the 'cell-impedance controlled' constraint during the wh ole lithium intercalation involving the ordering of lithium ion. (C) 2001 E lsevier Science B.V. All rights reserved.