Lithium intercalation into and deintercalation from Li1-delta Al1/4Ni3/4O2electrode: current transient analysis

The lithium intercalation into and deintercalation from Li1-8Al1/4Ni3/4O2 e lectrode was investigated by using current transient technique under large and small potential steps. From the fact that no potential plateau was obse rved in the charge-discharge curve, it was inferred that lithium-ion diffus ion proceeds in a single phase of the electrode. The 'reduced' current buil d-up and decay transients upon the large potential stepping were analysed a s compared with those current transients numerically simulated under the as sumption of the simple finite-length diffusion. From the appearance of the current build-up and decay transients, it was suggested that the Lithium tr ansport through the electrode is mainly governed by the lithium ion diffusi vity value during the lithium intercalation as well as deintercalation unde r the constant potential stepping. Also, the ratio of the transferred charg e (Q(int)/Q(deint)) calculated from the measured current build-up and decay transients upon each small potential stepping was discussed in terms of ca tion mixing between the Ni3+ and Li+ ions in the electrode. (C) 1999 Elsevi er Science S.A. tall rights reserved.