Cycling effects on interfacial reliability of TiO 2 anode film in thin film lithium-ion microbatteries

Abstract

This work presents a comprehensive study on the cycling effects on morphological, nanomechanical, and interfacial properties of sputtered TiO 2 anode film during discharge/charge cycling. TiO 2 film mechanically fails due to the repeated volume change and related generation/ relaxation of stress induced by electrochemical phase transformation. The induced stress intensifies the initiation/ propagation of cracks, also the interfacial delamination. Both morphology and mechanical property changes have harmful effects on the electrical contact, resulting in the battery aging. This paper also demonstrates that the experiment and analysis method is effective to characterize the interfacial reliability within thin film microbatteries.