A Piezo Smart-Braid Harvester and Damper for Multifunctional Fiber Reinforced Polymer Composites

Abstract

The past decade has seen the rapid development of wearable electronics, wireless sensor networks (WSNs), and self-powered implantable sensors. However, these devices usually require a continuous source of power supply to operate safely and accurately while having the least reliance on conventional battery systems—due to the recharging/maintenance burdens of batteries. Vibration-based piezoelectric energy harvesting (PEH) from environment, man-made machinery, and human body movements seems to be a promising solution. Herein, the first integration of a piezoelectric poly(vinylidene fluoride) (PVDF) yarn-braid microgenerator into a fiber reinforced polymer composite (FRPC) structure is reported. It is demonstrated that the developed smart composite exhibits multifunctional performances, including simultaneous structural (with ≈10% increased Young's modulus), energy harvesting, and vibration damping (with a damping factor of 125%). The results show that an average output voltage of 3.6 V and a power density of 2.2 mW cm−3 can be achieved at strains below 0.15%, under cyclic loading tests between 1 and 10 Hz. Moreover, noticeable improvements are made in the crystallinity percentage and β-phase content of as-received PVDF yarns by, respectively, ≈34% and ≈37%, as a result of the applied coreless radial and axial corona poling techniques.