Effect of layer morphology on the lithium-ion diffusion in thin LixCoO2 films

摘要

In general, the microstructure of materials can influence their transport properties. In our studies on the deposition of thin LivCoO2 films by the electrostatic spray deposition (ESD) technique, we have obtained five different types of layer morphologies as a result of varying deposition conditions, i.e. mainly deposition temperature and solvent composition. They are classified further into three major different structures, i.e. dense, fractal-like porous, and reticular porous [1,2]. Due to poor adhesion of a fractal-like porous LiCo02 layer to a metal substrate (stainless steel in our case) and loose interconnection between the LiCoCh particles, this structure is not suitable for batteries. However, a reticular LiCoCh layer reveals good adhesion to a metal substrate and is very strong. Therefore, we will only compare the lithium-ion diffusion in dense and reticular layers.