Excellent energy storage properties and fast discharging speed of BFO-based relaxor ferroelectric ceramics

The poor comprehensive energy storage performance (energy storage density and energy storage efficiency) is a key scientific problem to be solved in the field of energy storage ceramics. In this work, (0.67- x )BiFeO 3 - x Bi 0.1 Na 0·7 NbO 3 -0.33BaTiO 3 -0.15 wt%MnCO 3 (BNBFNT- x , x  = 0, 0.1, 0.2, and 0.3) ceramics were designed. The microstructure, dielectric properties , energy storage properties, and charge-discharge performances of BNBFNT- x ceramics were systematically investigated. The maximum recoverable energy density W rec of the BNBFNT-0.10 ceramic is 3.06 J/cm 3 with an efficiency of 81.4%. Apart from that, the ceramic also demonstrates excellent frequency (the variation of W rec in the frequency range of 10 Hz – 90 Hz is ± 6.4%) and thermal stability (the variation of W rec in the temperature range of 25 °C – 100 °C is ± 7.3%). Furthermore, the BNBFNT-0.10 ceramic has ultra-fast charge and discharge speeds (t 0.9  = 0.032 μs), a large power density ( P D  = 22.2 MW/cm 3 ), and an extremely high current density ( C D  = 355.6 A/cm 2 ).