Piezoelectric polymers, such as the Emfit polypropylene piezoelectret foam investigated in this study, have distinct advantages over traditional piezoceramics. Although piezopolymers have a smaller piezoelec tric coupling coefficient when compared to piezoceramics, they are well suited for in vivo applications , having a lead - free composition, for applications with curved or flexible surfaces, being flexible, or where weight or large shocks are factors, being l ight weight and r esilient. Presented here is an improved electromechanical multiple degree of freedom (MDOF) model of a mult ilayer piezoelectret foam stack that implements a complex stiffness damping model as a function of measureable material properties , as well as an updated stack configuration which makes use of lighter and more fle xible materials than the author’s previous configuration. The model predicts the energy harvesting performance of the stack at varying excitation frequencies and for varying s tack properties. Finally, the stack model parameters are validated with experimentally determined foam material properties .