Lead-Free Ceramics with High Energy Density and Reduced Losses for High Temperature Applications

The major limiting factors for the use of ceramic capacitors in power electronics are size and temperature stability. Ferroelectric ceramics very often exhibit high energy density, but fail to provide stable and efficient performance at high temperatures. Here, the authors report on a lead-free BiFeO3-SrTiO3 ceramic capacitor exhibiting unprecedented low dielectric loss and high thermal stability, while maintaining high energy density and fast discharge rates up to 200 degrees C. These unique properties clearly outperform other state of the art ceramics and potentially create significant new markets for high capacity ceramic capacitors at high frequencies and high temperature operations.