A comparative electrochemical study of LiMn2O4 spinel thin-film and porous laminate

Novel Electrostatic Spray Deposition (ESD) technique was used to fabricate LiMn2O4 spinel thin-films. Cyclic voltammograms of both the ESD and porous laminate films show the double peaks in the 4.0 V range characteristic of the LiMn2O4 spinel materials. The porous laminates exhibit two semicircles in the impedance spectra while the ESD films show only one single semicircle. The diffusion time constant in the laminate films was typically one order of magnitude larger than that in the ESD thin-films. The apparent lithium-ion chemical diffusion coefficient in LiMn2O4 was found to be of the order of 10(-9) cm(2)/s for both the porous laminate film and the ESD films despite the difference in the diffusion time constants. (C) 2002 Elsevier Science Ltd. All rights reserved.