Temperature stability and energy storage performances of Bi(Li1/3Hf2/3)O3-added BNT-based ceramics

The power electronics sector's growing demand requires the creation of energy storage systems with high recoverable energy storage density (Wrec) and efficiency (η). Although Bi0.5Na0.5TiO3 (BNT)-based ceramics are considered to be among the most promising dielectric materials, issues such as high energy loss (Wloss) and low breakdown strength (Eb) significantly affect their performance. Herein, the binary systems of (Bi0.5Na0.5)0.65(Ba0.3Sr0.7)0.35TiO3-xBi(Li1/3Hf2/3)O3 (BNBST-xBLH) are designed through the bandgap engineering and composition engineering strategies to achieve high Wrec and η. Consequently, the optimum composition of BNBST-0.15BLH delivers an optimally high Wrec of 4.3 J/cm3 and a desired conversion η of 92.3% at 370 kV/cm, while maintaining the variation of Wrec less than 9% and η less than 2%in the temperature range of room temperature (RT) to 200 °C. Combined with the extremely rapid discharge time τ0.9 of 74 ns and the high power density PD of 48.591 MW/cm3, the fabricated x = 0.15 ceramics are regarded to be viable lead-free options for practical applications.