Device for harvesting mechanical energy through a piezoelectrochemical effect

Abstract

Mechanical energy harvesting is an increasingly important method of providing power to distributed sensor networks where physical connection to a power source is impractical. Conventional methods use vibrations to actuate a piezoelectric element, coil/magnet assembly, or capacitor plates, thereby generating an electric current. The low charge-density of these devices excludes their application in low frequency and static load sources, with the lowest frequency reported devices limited to 10 Hz. These frequency limitations can be overcome by exploiting the piezoelectrochemical effect, a similar but physically distinct effect from the piezoelectric effect whereby an applied mechanical load alters the thermodynamics of an electrochemical reaction to produce a voltage/current. Piezoelectrochemical energy harvesters are expected to produce orders of magnitude more energy per load cycle than piezoelectrics and comparable power capabilities. These characteristics make piezoelectrochemical energy harvesters ideal for application in low-frequency and static loading scenarios for which conventional mechanical energy harvesting technology is poorly suited. Examples of such load sources include, but are not limited to, human footsteps, vehicular loads, and pressure vessels.