Dynamics of triboelectric nanogenerators: A review

Triboelectric nanogenerators (TENGs) represent a promising next-generation renewable energy technology. TENGs have become increasingly popular for harvesting vibration energy in the environment due to their advantages of lightweight, broad range of material choices, low cost, and no pollution. However, issues such as input force irregularity, working bandwidth, efficiency calculation, and dynamic modeling hinder the use of TENGs in industrial or practical applications. In this paper, the modeling process of the dynamical system of a TENG is reviewed from the perspective of energy flow. In addition, this paper reviews the main contributions made in recent years to achieve optimized output based on springs, magnetic forces, and pendulums, and introduces different ways to increase the bandwidth of TENGs. Finally, the main problems of TENGs in the process of harvesting vibration energy are discussed. This review may serve as a practical reference for methods to convert irregular mechanical input sources into optimized output performance toward the commercialization of TENGs.