Abstract

A d3i mode piezoelectric based vibration energy harvester (PVEH) has been successfully fabricated using screen printing technique for wireless micro sensor network applications. Polyvinylidene fluoride (PVDF), as a piezoelectric layer, was screen printed onto a glass substrate. The cured screen printed PVDF film was peeled off from the glass substrate and polarized by applying 10 kV across its layer. The polarized PVDF layer was sandwiched between two Metglas conductive electrodes, to form a d31 mode unimorph cantilever beam structure. The fabricated PVEH device was mechanically excited at its first resonance frequency (54 Hz) using base shaking experiments. The experimental results demonstrated that the developed energy harvester generated a maximum DC voltage of 1.35 V across a 10 Mfi load and a peak power output of 0.28 μW was delivered to a 1 MΩ resistive load at 0.53 V DC for a sinusoidal vibration of 15 g. The corresponding power density of the device was calculated to be 11.67 μW/cm3.