Model-based investigations of ferroelectric energy harvesting with regard to an improvement of life span and operability

Abstract

A new ferroelectric energy harvesting concept is investigated theoretically, based on a thermo-electromechanical multiscale constitutive framework in connection with the so-called condensed method. Taking advantage of comparatively large changes of strain and polarization due to domain switching, the electric output is higher compared to what is commonly known as piezoelectric energy harvesting. Dissipative self-heating and augmented damage accumulation, on the other hand, may impede the operability of the harvesting device, in particular if tensile stress is required for depolarization, as suggested by recent works. The new harvesting cycle thus dispenses with tensile stresses and instead exploits the potential of existing residual stresses. It is further investigated to which extent a bias field, commonly applied to support repolarization as an important stage of the cycle, can be omitted, saving considerable effort on the technical implementation. Process parameters are obtained from various simulations by pareto-optimization, considering, inter alia, the effect of ambient temperature.