Solution-derived lithium manganese oxide thin films with silver additive and their characterization

Ag-doped LiMn2O4 thin films derived from solution deposition were studied comparatively with LiMn2O4 by X-ray diffraction, scanning electron microscopy, electrochemical impedance spectroscopy, and galvanostatic charge–discharge experiments. The results show that the Ag-doped LiMn2O4 film is a composite of LiMn2O4 and Ag metal. The film is homogeneous and crack free with some conglomerations of silver. The Ag-doped LiMn2O4 thin-film has a lower polarization and offers higher capacity retention than the undoped one. The difference of capacity retention between the two films becomes larger with the increase of the charge–discharge current density, suggesting that the Ag-doped LiMn2O4 has a better cycling behavior, especially at higher charge–discharge current density.