Maximizing Ru-YSZ-Au battery capacity using an interfacial Ru:YSZ intermixed layer

Abstract

In the advanced materials and technology landscape, pursuing high-performance energy storage solutions for operating at elevated temperatures remains challenging. This study investigates the enhancement of a Ru-YSZ-Au energy storage device by incorporating an intermixed Ru:YSZ1:1 layer at the Ru/YSZ interface via atomic layer deposition. The structural and optical characterization through transmission electron microscopy, X-ray diffraction, energy-dispersive X-ray spectroscopy, electron energy loss spectroscopy, and ellipsometry confirmed the presence of metallic Ru within the YSZ matrix. Electrical measurements showed that this intermixed layer enhances the energy capacity, achieving a 230 % improvement in energy density compared to the reference device. However, introducing this layer also causes a voltage drop of 0.5 V, potentially due to defects formed during the atomic layer deposition of the Ru:YSZ1:1 layer. Despite this, the Ru-Ru:YSZ1:1-YSZ-Au device exhibits superior performance, demonstrating longer discharge times and higher energy densities, rivaling solid-state Li-ion micro-batteries across a wide temperature range.