High-Performance Piezoelectric Energy Harvesters and Their Applications

This paper presents a state-of-the-art review on a hot topic in the literature, i.e., vibration based energy harvesting techniques, including theory, modelling methods and the realizations of the piezoelectric, electromagnetic and electrostatic approaches. To minimize the requirement of external power source and maintenance for electric devices such as wireless sensor networks, the energy harvesting technique based on vibrations has been a dynamic field of studying interest over past years. One important limitation of existing energy harvesting techniques is that the power output performance is seriously subject to the resonant frequencies of ambient vibrations, which are often random and broadband. To solve this problem, researchers have concentrated on developing efficient energy harvesters by adopting new materials and optimising the harvesting devices. Particularly, among these approaches, different types of energy harvesters have been designed with consideration of nonlinear characteristics so that the frequency bandwidth for effective energy harvesting of energy harvesters can be broadened. This paper reviews three main and important vibration-to-electricity conversion mechanisms, their design theory or methods and potential applications in the literature. As one of important factors to estimate the power output performance, the energy conversion efficiency of different conversion mechanisms is also summarised. Finally, the challenging issues based on the existing methods and future requirement of energy harvesting are discussed.

A comprehensive review on vibration energy harvesting: Modelling and realization

The last decade has witnessed significant advances in energy harvesting technologies as a possible alternative to provide a continuous power supply for small, low-power devices in applications, such as wireless sensing, data transmission, actuation, and medical implants. Piezoelectric energy harvesting (PEH) has been a salient topic in the literature and has attracted widespread attention from researchers due to its advantages of simple architecture, high power density, and good scalability. This paper presents a comprehensive review on the state-of-the-art of piezoelectric energy harvesting. Various key aspects to improve the overall performance of a PEH device are discussed, including basic fundamentals and configurations, materials and fabrication, performance enhancement mechanisms, applications, and future outlooks.

A comprehensive review on piezoelectric energy harvesting technology: Materials, mechanisms, and applications

Energy harvesting technologies have been explored by researchers for more than two decades as an alternative to conventional power sources (e.g. batteries) for small-sized and low-power electronic devices. The limited life-time and necessity for periodic recharging or replacement of batteries has been a consistent issue in portable, remote, and implantable devices. Ambient energy can usually be found in the form of solar energy, thermal energy, and vibration energy. Amongst these energy sources, vibration energy presents a persistent presence in nature and manmade structures. Various materials and transduction mechanisms have the ability to convert vibratory energy to useful electrical energy, such as piezoelectric, electromagnetic, and electrostatic generators. Piezoelectric transducers, with their inherent electromechanical coupling and high power density compared to electromagnetic and electrostatic transducers, have been widely explored to generate power from vibration energy sources. A topical review of piezoelectric energy harvesting methods was carried out and published in this journal by the authors in 2007. Since 2007, countless researchers have introduced novel materials, transduction mechanisms, electrical circuits, and analytical models to improve various aspects of piezoelectric energy harvesting devices. Additionally, many researchers have also reported novel applications of piezoelectric energy harvesting technology in the past decade. While the body of literature in the field of piezoelectric energy harvesting has grown significantly since 2007, this paper presents an update to the authors' previous review paper by summarizing the notable developments in the field of piezoelectric energy harvesting through the past decade.

https://iopscience.iop.org/article/10.1088/1361-665X/ab36e4/pdf

A review of energy harvesting using piezoelectric materials: state-of-the-art a decade later (2008–2018)

We report a new type of phononic crystals with topologically nontrivial band gaps for both longitudinal and transverse polarizations, resulting in protected one-way elastic edge waves. In our design, gyroscopic inertial effects are used to break the time-reversal symmetry and realize the phononic analogue of the electronic quantum (anomalous) Hall effect. We investigate the response of both hexagonal and square gyroscopic lattices and observe bulk Chern numbers of 1 and 2, indicating that these structures support single and multimode edge elastic waves immune to backscattering. These robust one-way phononic waveguides could potentially lead to the design of a novel class of surface wave devices that are widely used in electronics, telecommunication, and acoustic imaging.

Topological Phononic Crystals with One-Way Elastic Edge Waves

Enhancing ability of harvesting energy from random vibration by decreasing the potential barrier of bistable harvester

We investigated the energy harvesting of a vertical beam with tip mass under vertical excitations. We applied dynamic unstability and internal resonance to improve the efficiency of harvesting. The experiments of harmonic excitation were carried out. Results show that for the beam there exist internal resonances in the dynamically unstable and the buckling bistable cases. The dynamic unstability is a determinant for strong internal resonance or mode coupling, which can be used to create a large output from piezoelectric patches. Then, the experiments of stochastic excitation were carried out. Results prove that the internal resonance or mode coupling can transfer the excitation energy to the low order modes, mainly the first and the second one. This can bring about a large output voltage. For a stochastic excitation, it is proved that there is an optimal weight of tip mass for realizing internal resonance and producing large outputs.

Energy harvesting by dynamic unstability and internal resonance for piezoelectric beam

This article investigates a dual-beam vibration energy harvester in which two piezoelectric cantilever beams are coupled by magnets The analytical solution of such a vibration energy harvester sys

Magnetically coupled dual-beam energy harvester: Benefit and trade-off:

Acoustic-elastic metamaterials and phononic crystals for energy harvesting: a review

In recent years, metamaterials for the applications in low-frequency vibration suppression and noise reduction have attracted numerous research interests. This paper proposes a metamaterial system with local resonators from adjunct unit cells coupled by negative stiffness springs. Frist, a lumped parameter model of the system is developed, and a stability criterion is derived. The band structure of the infinite lattice model is calculated. The result reveals the appearance of extra band gaps in the proposed metamaterial. A parametric study shows that the first extra band gap can be tuned to ultralow frequency by controlling the negative stiffness of the coupling springs. A transmittance analysis of the finite lattice model verifies the predictions obtained from the band structure analysis. Subsequently, the work is extended to a distributed parameter metamaterial beam model with the proposed configuration of coupled local resonators. The stability analysis shows that the infinitely long metamaterial beam becomes unstable as long as the stiffness of the coupling spring becomes negative. For the finitely long metamaterial beam, the stability could be achieved for negative coupling springs of given stiffnesses. The effects of the number of cells and the lattice constant on the system stability are investigated. The transmittance of the finitely long metamaterial beam is calculated. The result shows that due to the restriction on the tunability of negative stiffness for the proposed metamaterial beam, a quasistatic vibration suppression region can only be achieved when the number of cells is small.

Chunbo Lan

Papers

Enhancing ability of harvesting energy from random vibration by decreasing the potential barrier of bistable harvester

Energy harvesting by dynamic unstability and internal resonance for piezoelectric beam

Magnetically coupled dual-beam energy harvester: Benefit and trade-off:

Acoustic-elastic metamaterials and phononic crystals for energy harvesting: a review

Metamaterial With Local Resonators Coupled by Negative Stiffness Springs for Enhanced Vibration Suppression