Study of lithium insertion into electrochemically synthesized sodium-vanadium oxide

We report herein on the electroanalytical behavior of LixNayV2O5 electrodes that were synthesized electrochemically from aqueous solutions of vanadyl and sodium sulphates, followed by thermal annealing (300 degreesC). The ele ctrodes were comprised of monolithic layers deposited on a stainless steel plate. A capacity above 200 mAh/g could be obtained at relatively high rate s (>C/3 h) and prolonged cycling (hundreds of charge-discharge cycles). As evident from FTIR and XPS measurements, the electrodes develop surface film s due to interactions with CO2 in the air and solution species. Electroanal ytical data obtained from slow scan rate cyclic voltammetry (SSCV), potenti ostatic intermittent titration (PITT), and impedance spectroscopy (EIS) are discussed. (C) 2001 Elsevier Science B.V. All rights reserved.