A Review on Piezoelectric Energy Harvesting: Materials, Methods, and Circuits

Abstract

Piezoelectric microelectromechanical systems (PiezoMEMS) are attractive for developing next generation self-powered microsystems. PiezoMEMS promises to eliminate the costly assembly for microsensors/microsystems and provide various mechanisms for recharging the batteries, thereby, moving us closer towards batteryless wireless sensors systems and networks. In order to achieve practical implementation of this technology, a fully assembled energy harvester on the order of a quarter size dollar coin (diameter = 24.26 mm, thickness = 1.75 mm) should be able to generate about 100 μW continuous power from low frequency ambient vibrations (below 100 Hz). This paper reviews the state-of-the-art in microscale piezoelectric energy harvesting, summarizing key metrics such as power density and bandwidth of reported structures at low frequency input. This paper also describes the recent advancements in piezoelectric materials and resonator structures. Epitaxial growth and grain texturing of piezoelectric materials is being developed to achieve much higher energy conversion efficiency. For embedded medical systems, lead-free piezoelectric thin films are being developed and MEMS processes for these new classes of materials are being investigated. Nonlinear resonating beams for wide bandwidth resonance are also reviewed as they would enable wide bandwidth and low frequency operation of energy harvesters. Particle/granule spray deposition techniques such as aerosol-deposition (AD) and granule spray in vacuum (GSV) are being matured to realize the meso-scale structures in a rapid manner. Another important element of an energy harvester is a power management circuit, which should maximize the net energy harvested. Towards this objective, it is essential for the power management circuit of a small-scale energy harvester to dissipate minimal power, and thus it requires special circuit design techniques and a simple maximum power point tracking scheme. Overall, the progress made by the research and industrial community has brought the energy harvesting technology closer to the practical applications in near future.

Advances in Piezoelectric Polymer Composites for Energy Harvesting Applications: A Systematic Review

“…There exist about 200 piezoelectric materials for energy harvesting applications out of which piezo‐ceramics (mainly PZT and BaTiO 3 ) have attracted major attention due to their better piezoelectric properties as compared to other piezoelectric materials . A wide range of piezoelectric ceramics (PZT‐based thin films and lead‐free ceramic films) and their applicability toward transducers and energy harvesting areas have been elucidated by Khan et al .…”

On the energy localization in weakly coupled oscillators for electromagnetic vibration energy harvesting

“…Ambient vibration-based energy harvesters with the ability to convert mechanical vibrations to electrical energy are among these technologies with potential applications for low-powered electronic devices. So far, vibration energy harvesters have been commonly based on four different conversion techniques namely piezoelectricity [2,3], electromagnetism [4,5], electrostatics [6] for MEMS technology and magnetostricton [7,8].…”

Control of electro-chemical processes using energy harvesting materials and devices

“…222 To date, rectification methods applied to electro-chemical systems have been relatively simple, such as simple diode and full wave rectification, while in conventional harvesting applications a range power management circuits have been developed to minimise losses and optimise impedance matching of the harvester to the electrical load; this provides scope for further improvement in the electro-chemical applications. 223 Greater information regarding overall efficiencies of systems would also be of interest. For solar harvesting, the system efficiencies are more widely reported, and the other harvesting approaches would benefit from similar information.…”