A cylindrical bistable hybrid triboelectric-electromagnetic energy harvester for harvesting low-frequency vibration energy

Low-frequency vibration is abundantly available in mechanical equipment and engineering structures, yet the conventional energy harvesters exhibit limited efficiency in low-frequency vibration energy harvesting. To address this challenge, this study presents a cylindrical bistable hybrid triboelectric-electromagnetic energy harvester (CBH-TEEH). The overarching goal of this study is to utilize the CBH-TEEH for efficient low-frequency vibration energy harvesting. The core innovation of the CBH-TEEH lies in integrating a bistable mechanical mechanism with hybrid triboelectric-electromagnetic systems, which is capable of transforming low-frequency vibration into large-amplitude dynamic responses, thereby enabling efficient low-frequency vibration energy harvesting. Firstly, the prototype design and the theoretical model are introduced. Then, the performance of the CBH-TEEH are thoroughly explored, with comprehensive discussions on how critical parameters influence energy harvesting efficiency and bandwidth broadening. Finally, the experimental validation and application demonstration are conducted. At 7 Hz, the CBH-TEEH achieves the optimal output power of 25.49 mW, which is 21.6 times the output of a single bistable TENG. In addition, the CBH-TEEH can successfully power LED array and the temperature-humidity sensor. Therefore, the CBH-TEEH can harvest the low-frequency vibration energy efficiently, and has potential applications in the field of self-powered sensor and structural health monitoring for engineering structures.