Electrical engineering

Physics

Capacitor

Energy storage

Engineering

Dielectric

Ceramic

Voltage

Composite material

Power (physics)

Materials science

Power density

Quantum mechanics

Pulsed power

Optoelectronics

Microstructure

ACS Sustainable Chemistry & Engineering

Recently, ceramic capacitors with fast charge–discharge performance and excellent energy storage characteristics have received considerable attention. Novel NaNbO3-based lead-free ceramics (0.80NaNbO3-0.20SrTiO3, abbreviated as 0.80NN-0.20ST), featuring ultrahigh energy storage density, ultrahigh power density, and ultrafast discharge performance, were designed and prepared in this study. These 0.80NN-0.20ST ceramics exhibited a high breakdown strength of 323 kV/cm, attributable to their small grain size and dense microstructure, a recoverable energy storage density of 3.02 J/cm3, and an energy storage efficiency of 80.7% at an applied electric field of 310 kV/cm. The excellent stability of energy storage properties in frequency (0.1–1000 Hz), temperature (20–120 °C), and fatigue resistance (cycle number: 105) were also observed in the 0.80NN-0.20ST ceramics. In contrast with other recently reported lead-free ceramic-based dielectric capacitors, the 0.80NN-0.20ST ceramics display a high energy storage efficiency combined with a high recoverable energy storage density, which indicates that they have wide application foreground and potential in the field of energy storage. These ceramics also show a considerable current density of 677 A/cm2, an ultrahigh power density of 23.7 MW/cm3, and a short release duration (∼225 ns). This study brings the NaNbO3-based ceramics into a new chapter of research and application of energy storage dielectric capacitors.

Novel Sodium Niobate-Based Lead-Free Ceramics as New Environment-Friendly Energy Storage Materials with High Energy Density, High Power Density, and Excellent Stability