Development, presentation and tests of a hybrid thermal vibrational energy harvester based on lead free piezoelectric material

Piezoelectric and pyroelectric effects are well known and have been widely used in the field of energy harvesting, actuators or sensors. This paper presents a cantilever structure based on a lead free piezoelectric-pyroelectric hybrid transducer based on PVDF (Polyvinylidene fluoride) piezoelectric, a Lithium Niobate piezoelectric, and a SMA (Shape Memory Alloy) materials which is capable of simultaneously harvesting mechanical and thermal energies. The piezoelectric cantilever has been studied using finite element modeling for application in self-powered sensors in automobiles. The cantilever are able to resonate under 300 Hz of frequency range. We calculated the output voltage from both the thermal and vibrational excitations with the help of Comsol Multiphysics finite-element software. We shows that the configuration in which the PVDF is the top layer, then SMA as the middle layer and Lithium niobate as the bottom layer has the highest value of harvested energy with an output voltage up to 12Vpp.