BaTiO3-NaNbO3 energy storage ceramics with an ultrafast charge-discharge rate and temperature-stable power density

Dielectric capacitors with ultrafast charge-discharge rates are extensively used in electrical and electronic systems. To meet the growing demand for energy storage applications, researchers have devoted significant attention to dielectric ceramics with excellent energy storage properties. As a result, the awareness of the importance of the pulsed discharge behavior of dielectric ceramics and conducting characterization studies has been raised. However, the temperature stability of pulsed discharge behavior, which is significant for pulsed power applications, is still not given the necessary consideration. Here, we systematically investigate the microstructures, energy storage properties and discharge behaviors of nanograined (1-x)BaTiO3-xNaNbO3 ceramics prepared by a two-step sintering method. The 0.60BaTiO3-0.40NaNbO3 ceramics with relaxor ferroelectric characteristics possess an optimal discharge energy density of 3.07 J cm-3, a high energy efficiency of 92.6%, an ultrafast discharge rate of 39 ns and a high power density of 100 MW cm-3. In addition to stable energy storage properties in terms of frequency, fatigue and temperature, the 0.60BaTiO3-0.40NaNbO3 ceramics exhibit temperature-stable power density, thereby illustrating their significant potential for power electronics and pulsed power applications.