LiCoO2 thin films were prepared by pulsed laser deposition (PLD) on Pt/Ti/SiO2/Si (Pt) and Au/MgO/Si (Au) substrates, respectively. Crystal structures and surface morphologies of thin films were investigated by X-ray diffraction (XRD) and field emission scanning electron microscopy (FESEM). The LiCoO2 thin films deposited on the Pt substrates exhibited a preferred (0 0 3) texture with smooth surfaces while the LiCoO2 thin films deposited on the An substrates exhibited a preferred (104) texture with rough surfaces. The electrochemical properties of the LiCoO2 films with different textures were compared with charge-discharge, dQ/dV, and Li diffusion measurements (PITT). Compared with the (I 04)-textured LiCoO2 thin films, the (0 0 3)-textured thin films exhibited relatively lower electrochemical activity. However, the advantage of the (10 4)-textured film only remained for a small number of cycles due to the relatively faster capacity fade. Li diffusion measurements showed that the Li diffusivity in the (0 0 3)-textured film is one order of magnitude lower than that in the (10 4)-textured film. As discussed in this paper, we believe that Li diffusion through grain boundaries is comparable to or even faster than Li diffusion through the grains. (c) 2007 Elsevier Ltd. All rights reserved.