High energy storage efficiency and exceptional recoverable energy storage density achieved in KNN-based ceramics via entropy engineering
Year: 2025
Type: article
Abstract: Dielectric capacitors possess significant advantages in terms of fast charge and discharge. Therefore, they are recognized as the most promising candidates for the next generation of high-performance pulsed power systems. Nevertheless, achieving ultra-high recoverable energy storage density ( W rec ) along with ultrahigh efficiency ( η ) poses a significant challenge. This challenge hinders the miniaturization and integration of cutting-edge energy storage devices. In this study, a high-entropy strategy is utilized to construct ultrafine grains (submicron). These grains feature a compact microstructure, enhanced electrical homogeneity, a wider bandgap, and polar nanoregions (PNRs). Such properties lead to an improved breakdown strength , a delay in polarization saturation, and enhanced relaxation behavior. As a result, the KNN-0.15 ceramic exhibits a recoverable energy density value of 6.36 J∙cm −3 and an efficiency of 84 % at an electric field strength of 580 kV∙cm −1 . Furthermore, the ceramic capacitor showcases a power density of approximately 436.5 MW∙cm −3 and a discharge energy density of around 4.3 J∙cm −3 at 160°C. Notably, its variability remains below 3 % across a broad temperature range from 20 to 160°C. These achievements are propelling the field forward, aiming to develop more practical and powerful dielectric materials for energy storage.
Source: Journal of Alloys and Compounds
Institution: Shaanxi University of Science and Technology
Language: English
Subfield: Materials Chemistry
Field: Materials Science
Domain: Physical Sciences
Open Access status: hybrid
Estimated APC paid: $3,660
Awards: G6348810055, G7753372887
OpenAlex ID: W4409166964