Additively Manufactured Low-frequency Piezoelectric Energy Harvester Design: Modeling, Fabrication, And Experiment

Abstract

With conventional energy sources like fossil fuels becoming increasingly scarce and the widespread adoption of electric vehicles placing growing demands on lithium, the primary material in battery manufacturing, there is a critical need for scientists and engineers to explore alternative energy sources for powering microelectronic devices. Among these alternatives, integrating piezoelectric materials within cantilever beam structures for energy harvesting applications is a promising solution, attributed to its straightforward design and ability to undergo significant deformation under applied loads.

However, this technological approach faces notable challenges, including limitations associated with low power density and a high natural frequency due to inherent geometric constraints. These challenges have become a focal point for ongoing research endeavours to enhance the efficiency and applicability of piezoelectric energy harvesting. This thesis delves into a prospective solution for powering microelectronic devices, emphasizing its merits in terms of uncomplicated packaging and advancements in micro-scale power density. A MEMS ring-shaped piezoelectric energy harvesting device was fabricated, utilizing 3D printing for substrate production and precision dicing techniques to achieve the required dimensions of the piezoelectric material. The device's design was modelled using SOLIDWORKS, and its performance was thoroughly simulated in COMSOL to ensure alignment with observations.

Inspired by the Vesper microphone's square form, the energy harvester's geometric configuration offers scalability and the potential for incorporating multiple cantilever beams. According to the findings, this energy harvester demonstrates a total power output of 53.46 $\mu$W when subjected to an acceleration of 0.08g, establishing its promising viability relative to other energy harvesting technologies. The study presents a novel approach to energy harvesting and highlights the practical implications and potential advancements in micro-scale power generation for sustainable electronic devices.