Enhancing pulse energy‐storage properties of BaTiO3‐based ceramics using novel glass additive

Abstract

AbstractA novel glass additive of 10Bi2O3‒5Li2O‒7.5Na2O‒7.5K2O‒21Nb2O5‒20.5SiO2‒10.5BaO‒11SrO‒4.5Al2O3‒0.5La2O3‒2TiO2 was melted to improve the energy‐storage properties of (Ba0.94Li0.02La0.04)(Mg0.04Ti0.96)O3 (BLLMT) ceramics (BLLMT‒x wt% G), which overcomes the paradox between polarization and voltage endurance. The dielectric constant and resistance of BLLMT ceramics are improved by glass modification, while the grain size decreases. Consequently, excellent breakdown strength of 565.9 kV/cm is obtained, and the difference between maximum polarization and remnant polarization reaches up to 22.14 µC/cm2. Weibull distribution and finite element simulation prove that grain boundary density, grain size, resistance, and bandgap width have significant effects on the breakdown strength. Finally, outstanding energy‐storage density of 4.82 J/cm3 is obtained at x = 2, accompanied with an excellent pulse discharged energy density of 3.42 J/cm3, current density of 1226.12 A/cm2, and power density of 337.19 MW/cm3. Excellent temperature stability is gained with the variation of the pulse discharged energy density less than 10% at 20°C‒140°C. The outstanding pulse energy‐storage parameters are related to phase structure, small grain size, high grain boundary density, formation of liquid phase, increased ceramic resistance, and destroyed long‐range ordered ferroelectrics. This work provides a novel idea for fabricating glass to obtain excellent energy‐storage performance and promotes practical application of BaTiO3 ceramics.