Deposition and performance of all solid-state thin-film lithium-ion batteries composed of amorphous Si/LiPON/VO-LiPO multilayers

Abstract

Recently, thin-film lithium-ion batteries have attracted considerable attention as the micro-power sources for micro-sensors. In this study, we fabricated all solid-state thin-film lithium-ion batteries composed of amorphous multilayers and evaluated their charge-discharge characteristics in atmospheric conditions. The thin-film batteries were composed of an amorphous multilayer structure of lithium-doped vanadium oxide, lithium phosphorus oxynitride (LiPON), and Si as cathode, electrolyte, and anode, respectively. To obtain a good interface with the LiPON electrolyte, we deposited a multilayer cell structure by successive deposition in a vacuum chamber with a multi-target sputtering machine equipped with a movable shadow mask. We measured the charge and discharge characteristics of the thin-film batteries under atmospheric conditions without protection layers on the thin-film batteries. We observed large unit area capacities of 32.8 and 15.7 μAh/cm2 at the first charge and discharge cycle, respectively, in the voltage range of 0.5–3.0 V.