Realizing ultrahigh breakdown strength and ultrafast discharge speed in novel barium titanate-based ceramics through multicomponent compounding strategy

Lead-free dielectric ceramics have been an important section (segment) in the energy storage field. In this work, a synergistic optimization strategy of multicomponent compounding involving 0.9[0.88Ba 1- x Ca x TiO 3 -0.12Bi(Mg 2/3 (Nb 0.85 Ta 0.15 ) 1/3 )O 3 ]-0.1Bi 0.5 Na 0.5 TiO 3 (B 1- x C x T-BMNT-BNT) ceramics were proposed. With the increase of Ca 2+ content ( x ), the content of the CaTiO 3 phase increases, which obviously enhances the breakdown strength (BDS) and energy storage properties. The optimal energy storage performances were obtained in the B 0.6 C 0.4 T-BMNT-BNT ceramic, showing a large recoverable energy density ( W rec ) of 3.59 J/cm 3 and ultrahigh efficiency ( η ) of 90.86% at 430 kV/cm. Meanwhile, the B 0.6 C 0.4 T-BMNT-BNT material also exhibits good temperature stability (20~180°C), frequency stability (1~500 Hz) and fatigue resistant (1~10 5 cycles). In addition, the B 0.6 C 0.4 T-BMNT-BNT ceramic also possesses ultrafast discharge time ( t 0.9 = 38.6 ns) in the charge and discharge test. The above merits make the B 0.6 C 0.4 T-BMNT-BNT ceramic a promising candidate for wide-temperature dielectric capacitors in pulse power applications.