Achieving High Energy Storage Performance under a Low Electric Field in KNbO₃-Doped BNT-Based Ceramics

Abstract

Ceramic capacitors have great potential for application in power systems due to their fantastic energy storage performance (ESP) and wide operating temperature range. In this study, the (1 − x)Bi 0.5 Na 0.47 Li 0.03 Sn 0.01 Ti 0.99 O 3 -xKNbO 3 (BNLST-xKN) energy storage ceramics were synthesized through the solid-phase reaction method. The addition of KN disrupts the long-range ferroelectric order of the BNLST ceramic, inducing the emergence of polar nanoregions (PNRs), which enhances the ESP of the ceramics. The BNLST-0.2KN ceramic demonstrates a high recovered energy density (W rec ∼ 3.66 J/cm 3 ) and efficiency (η ∼ 85.8%) under a low electric field of 210 kV/cm. Meantime, it exhibits a large current density (C D ∼ 831.74 A/cm 2 ), high power density (P D ∼ 78.86 MW/cm 3 ), and fast discharge rate (t 0.9 ∼ 0.1 μs), along with good temperature stability and excellent fatigue stability. These properties make the BNLST-0.2KN ceramic a promising candidate for energy storage applications in low electric fields.

A polarization double-enhancement strategy to achieve super low energy consumption with ultra-high energy storage capacity in BCZT-based relaxor ferroelectrics

“…Dielectric energy storage capacitors, which are considered the most promising candidates for next-generation high-power systems, have attracted considerable research attention in recent decades due to their superfast charge–discharge speed and good reliability after long-term use. 1–12 According to the Ragone plots displayed in Fig. S1 (ESI†), however, no single energy storage device can simultaneously possess high energy storage density ( W rec ) and power density ( P d ), commonly regarded as two key figures-of-merit of power systems.…”