Flexible Ferroelectret Polymer for Self-Powering Devices and Energy Storage Systems

Applying
flexible materials for energy scavenging from ambient
mechanical vibrations is a clean energy solution that can help alleviate
electrical power demands in portable devices and wearable electronics.
This work presents fundamental studies on a flexible ferroelectret
polymer with a strong piezoelectric effect and its interface with
self-powered and energy storage systems. A single-layered device with
a thickness of 80 μm was used for characterizing the device’s
output voltage, current, transferred charge, and energy conversion
efficiency. The potential capability of harvesting mechanical energy
and delivering to system load is demonstrated by integrating the device
into a fully integrated power management system. The theory for determining
the harvested energy that is ultimately delivered to external electronic
loads (or stored in a battery) is discussed. The maximum power delivery
is found to be for a 600 MΩ load, which results in a device
power density of 14.0 W/m3 for input mechanical forces
with a frequency around 2 Hz.