Characterization of Tantalum Oxide–Ruthenium Oxide Hybrid Capacitors

The ac and dc performance and leakage current of Evans tantalum oxide-ruthenium oxide hybrid capacitors were characterized at room temperature. The RC time constants were in the range from 2 to 0.45 ms and dependent on the maximum operational voltage of the capacitor. The gravimetric and volumetric energy densities of hybrid capacitors were in the range of 0.074-0.233 J/g and 0.388-1.384 J/cm/sup 3/, respectively. The gravimetric and volumetric power densities of hybrid capacitors were in the range of 19-259 W/g and 100-1540 W/cm/sup 3/, respectively. A comparison of the performance between hybrid capacitors to conventional aluminum and tantalum electrolytic capacitors is made in this paper.