Giant Electro-Mechanical Energy Conversion in Lead-Free Ferroelectric Materials

Abstract

The authors present a novel approach for electro-mechanical energy conversion over a wide frequency domain by employing lead-free ferroelectric ceramics. The methodology aims at utilizing Ericsson-like cycle for giant electromechanical energy conversion. Systematic application of electrical and mechanical fields for cyclic polarization switching leads to enhanced energy generation densities. The reported energy density, achieved by using 0.94(Bi_0.5Na_0.5)TiO₃–0.05(BaTiO₃)–0.01(K_0.5Na_0.5)NbO₃ lead-free ferroelectric ceramic, is three orders of magnitude larger than that reported for leading lead-based ferroelectric materials. Estimated energy density was found to be 940kJ.m⁻³ which is significantly higher than conventional piezoelectric harvesters.

Keywords:

• Lead-free
• ferroelectric
• energy harvesting
• Ericsson cycle