A diffusion kinetics study of Li-ion in LiV3O8 thin film electrode

The kinetic behaviors of Li-ion insertion/extraction in LiV3O8 thin film have been investigated using cyclic voltammetry (CV), potentiostatic intermittent titration (PITT) and electrochemical impedance spectroscopy (EIS) method. This LiV3O8 thin film with a mixed amorphous-nanocrystalline microstructure was fabricated by RF sputtering. For the first time, the intrinsic kinetics of LiV3O8 thin film electrode is obtained. The DLi+DLi+ value is about 10−13 cm2/s in mixed amorphous-nanocrystalline microstructure LiV3O8 thin film. Different to crystalline LiV3O8 thin film, the DLi+DLi+ values do not change a lot with the increase of cell potential which is due to the absence of structural phase transition behavior in mixed microstructure LiV3O8 thin film during Li+ insertion/extraction process. This is also the reason for excellent capacity retention performance of LiV3O8 film with a mixed microstructure.