Composite piezoelectric energy harvesters with symmetric angle-ply stacking sequences and variable through-the-thickness Poisson’s ratios

We evaluate in this work the effect of symmetric carbon fiber composites laminates with angle-ply stacking sequences ( ) in the design of composite piezoelectric energy harvesters (PEHs). Some of those specific stacking sequences also feature negative Poisson’s ratio (NPR) or near zero Poisson’s ratio (NZPR) through the thickness for ply angles . We consider here six different architectures all with similar in-plane elastic modulus and different positive and negative Poisson’s ratio v13 values. Finite element models are developed to understand the distribution of the voltage density of the laminates with the different stacking sequences and their bending properties. Experimental tests (3-point bending and vibration) are also performed. Both the simulations and the experimental results show that the PEH with the stacking sequences of near zero generate the highest power compared with the other composite energy harvesters. The maximum voltage FRFs (Frequency response functions) happens at the fundamental resonance, and the PEH with near zero has also the lowest resonance frequency compared to the other stacking sequences.