# High Energy Storage Performance in Bi0.46Sr0.06Na0.5TiO3/CaTiO3 Relaxor Ferroelectric Ceramics

## TL;DR

This study explores a new lead-free ceramic material with high energy storage performance suitable for pulse system applications.

## Contribution

The novel contribution is the synthesis of (Bi0.46Sr0.06Na0.5TiO3−xCaTiO3 ceramics with optimized energy storage properties through Sr2+ and CaTiO3 adjustments.

## Key findings

- The ceramics achieved a maximum energy storage density of 3.52 J/cm3 with a breakdown field of 260 kV/cm.
- The material showed good dielectric stability across a wide temperature and frequency range.
- It demonstrated a maximum power density of 18.90 MW/cm3 and current density of 349.58 A/cm2.

## Abstract

(Bi0.5Na0.5)TiO3-based lead-free ferroelectric ceramics are among the most extensively researched energy storage materials today. In this paper, (1 − x)Bi0.46Sr0.06Na0.5TiO3−xCaTiO3 ceramics were synthesized through a solid-phase sintering method by synergistically adjusting CaTiO3 components after introducing Sr2+ at the A-site. The XRD patterns revealed that all samples formed a single perovskite solid solution, with the 111 and 200 peaks shifting to higher levels as the CaTiO3 increased, indicating a gradual decrease in cell volume. The SEM images exhibited dense crystals without any apparent porosity, which were formed by the different components of the ceramics. Through energy storage, dielectric, and charge–discharge performance tests, it was found that with a 10%mol CaTiO3 addition, the samples obtained a maximum breakdown field strength of 260 kV/cm and corresponding saturation polarization strength of 32.80 μC/cm2 and thereby exhibited a reversible energy storage density valued 3.52 J/cm3. In addition, the dielectric constant varied by less than 10% within the temperature range of 63.7 °C to 132.7 °C and presented good frequency (10–250 Hz) stability at 180 kV/cm. Moreover, the ceramics demonstrated a maximum current density reaching 349.58 A/cm2 and a maximum power density of 18.90 MW/cm3 for their charge–discharge performance, all of which makes them suitable for pulse system applications.