Microstructural effects on capacity-rate performance of vanadium oxide cathodes in lithium-ion batteries

Abstract

Vanadium oxide thin film cathodes were analyzed to determine whether smaller average grain size and/or a narrower average grain size distribution affects the capacity-rate performance in lithium-ion batteries. Vanadium oxide thin films were prepared by sputtering onto ITO-coated glass substrates and crystallized in a refined annealing process to generate diverse microstructures. Average grain size and grain size distribution were determined in SEM analysis. No significant difference was observed in capacity rate behavior with changes in microstructure. However, it is speculated that further in situ analysis may show different relative diffusion rates into grains of differing sizes is related to different microstructures.