Electrochemical properties of LiCoO2 thick-film cathodes prepared by screen-printing technique

A screen-printing process is used to prepare thick Zr-incorporated LiCoO2 (Zr–LiCoO2) films up to 20 μm. The sol slurry used for the screen-printing consists of a Zr–LiCoO2 sol and the Zr–LiCoO2 powder. The microstructure and morphology of the films are investigated. After a thermal treatment, crack-free crystalline films are obtained. The electrochemical properties of the thick films are investigated in a half-cell with a Li-metal anode and in a full-cell with a Fe/Si multilayer film anode. Excellent cycleability is observed. Incorporation of 5 wt.% Ag powder into the sol slurry for screen-printing improves the electrochemical performance such as the charge–discharge coulombic efficiency. This is attributed to enhanced electrical conductance. It is found, however, that the degree of utilization of the electrode material decreases with increasing film thickness.