A self-amplifying dielectric-elastomer-amplified piezoelectric for motion-based energy harvesting

Abstract

The dielectric elastomer generator is a stretchable generator that converts low-frequency motions into electrical output, with excellent impedance matching capabilities. However, the dielectric elastomer requires an external high-voltage priming source to initialize its operation. We previously proposed a piezoelectric generator as the priming source, and demonstrated a net amplification of specific output energy of 1.8 times by the dielectric elastomer generator, as compared with that of the piezoelectric working in isolation. We termed our prototype the dielectric-elastomer-amplified piezoelectric (DEAmP). In this version, we introduce a self-priming circuit that will progressively charge up the dielectric elastomer generator to a much higher potential, thereby allowing the system to approach its optimized operating voltage. We term this the DEAmPx generator, with the letter “x” denoting progressive voltage/charge amplification by the self-priming circuit. The DEAmPx attained an output voltage of about 2000 V in 18 cycles and generates a dielectric elastomer generator–specific energy output of 3.1 mJ/g per cycle—19 times higher than that of the piezoelectric generator working in isolation. The system-specific energy output of DEAmPx is 0.49 mJ/g, with just a single layer of elastomer film. With this significantly larger output, we demonstrate the capability of a single-layer DEAmPx to power dielectric elastomer actuators.