Degradation of Piezoelectric Materials for Energy Harvesting Applications

Abstract

The purpose of energy harvesting is to provide long term alternatives to replaceable batteries across a number of applications. Piezoelectric vibration harvesting provides advantages over other transduction methods due to the ability to generate large voltages even on a small scale. However, the operation in energy harvesting is di↵erent from typical sensors or actuators. The applied stress is often at the material limit in order to generate the maximum power output. Under these conditions, the degradation of the materials becomes an important factor for long term deployment. In this work bimorph piezoelectric beams were subjected to lifetime testing through electromagnetic tip actuation for a large number of cycles. The results of two measurement series at di↵erent amplitudes are discussed. The dominant e↵ect observed was a shift in mechanical resonance frequencies of the beams which could be very detrimental to resonant harvesters. 1.