Perovskite Srx(Bi1−xNa0.97−xLi0.03)0.5TiO3 ceramics with polar nano regions for high power energy storage

Jiyue Wu,Amit Mahajan,Lars Riekehr,Hangfeng Zhang,Bin Yang,Nan Meng,Zhen Zhang,Haixue Yan

doi:10.1016/j.nanoen.2018.06.016

Jiyue Wu, Amit Mahajan + Show 6 more

Open Access

https://doi.org/10.1016/j.nanoen.2018.06.016

Copy DOI

Abstract

Dielectric capacitors are very attractive for high power energy storage. However, the low energy density of these capacitors, which is mainly limited by the dielectric materials, is still the bottleneck for their applications. In this work, lead-free single-phase perovskite Srx(Bi1−xNa0.97−xLi0.03)0.5TiO3 (x = 0.30 and 0.38) bulk ceramics, prepared using solid-state reaction method, were carefully studied for the dielectric capacitor application. Polar nano regions (PNRs) were created in this material using co-substitution at A-site to enable relaxor behaviour with low remnant polarization (Pr) and high maximum polarization (Pmax). Moreover, Pmax was further increased due to the electric field induced reversible phase transitions in nano regions. Comprehensive structural and electrical studies were performed to confirm the PNRs and reversible phase transitions. And finally a high energy density (1.70 J/cm3) with an excellent efficiency (87.2%) was achieved using the contribution of field-induced rotations of PNRs and PNR-related reversible transitions in this material, making it among the best performing lead-free dielectric ceramic bulk material for high energy storage.

Highlights

Due to the rapid development of electronic devices and power systems, the demand for high power energy storage has been increased significantly in recent years [1,2]
Even though the energy density of ceramic capacitors can be improved by higher applied electrical field, the energy efficiency will be significantly degraded due to higher conductivity and/or irreversible transitions caused by high field [12,13]
A notable improvement in both the energy density and the energy efficiency of ceramic capacitors is critical for their practical applications [14]

Summary

Introduction

Due to the rapid development of electronic devices and power systems, the demand for high power energy storage has been increased significantly in recent years [1,2]. Even though the energy density of ceramic capacitors can be improved by higher applied electrical field, the energy efficiency will be significantly degraded due to higher conductivity and/or irreversible transitions caused by high field [12,13]. A notable improvement in both the energy density and the energy efficiency of ceramic capacitors is critical for their practical applications [14]. Dielectric oxides thin films usually possess much larger energy density than bulk ceramics since they can withstand higher electric fields before breakdown. Their practical applications are limited by the substrate effects and difficulties in up-scaling process [15]. Bulk ceramics offer much larger effective volume and much wider working temperature range for energy storage [16]

Methods

Results

Conclusion