Enhanced energy storage and fast charge-discharge capability in Ca0.5Sr0.5TiO3-based linear dielectric ceramic

Ca0.5Sr0.5(TaxTi1-1.25x)O3-2 wt%SiO2 ceramic samples were fabricated by solid state method. XRD data showed all samples are assigned to perovskite structure, dense microstructure and relatively large grain size were displayed by SEM. Moreover, the effect of Ta5+ ion doping on increased resistivity and energy barrier height were analysed by impendance spectra. Exceptional energy storage performances which are 2 J/cm3 in energy density and 96% in energy efficiency under breakdown strength of 360 kV/cm can be obtained in the sample with x = 0.024, also possessing over 80% efficiency in a wide range of temperature (20–120 °C). Additionally, pulsed charging and discharging tests were carried out aiming to evaluate the practical performance of ceramic materials. The prominent parameters Imax of 32.2 A, CD of 256.1 A/cm2, PD of 15.4 MW/cm3 and outstanding temperature stability (20–120 °C) were achieved in the sample with x = 0.024 as well, releasing stored energy sharply (t0.9