9 - Lead-based and lead-free ferroelectric ceramic capacitors for electrical energy storage

Abstract

The rapidly growing demands for electrical energy storage devices have motivated intense research efforts on respective technologies. Electrostatic capacitors, made up of dielectrics, display giant power density as well as ultrashort discharge times, which make them useful as energy storage devices employed in pulsed power systems. Nevertheless, the low energy density of the electrostatic capacitors is a significant limitation, which necessitates the use of many capacitor arrays making the storage devices bulky. Hence, efforts on the capacitors, for pulsed power applications, have been focused mainly on developing dielectric materials with high-energy density and storage efficiency together with good fatigue endurance and thermal stability. In this regard, dielectric materials based on polymers, glasses, and ceramics, belonging to linear dielectrics, paraelectrics, ferroelectrics, relaxor ferroelectrics, and antiferroelectrics, have been studied. This chapter broadly covers the studies on energy storage properties of lead-based and lead-free ferroelectric, relaxor ferroelectric, and antiferroelectric bulk ceramics and films. Employment of dielectric capacitors in pulsed power systems and their applications, figures of merit for energy storage performance, and the dielectric properties influencing them are also discussed.