Highly Robust Self-Switching Mode Triboelectric Nanogenerator Based on Misaligned Triple-Cam Design

To enhance the robustness and lifespan of triboelectric nanogenerator (TENG) and facilitate its industrial applications, herein, a self-switching mode TENG that combines the advantages of contact mode and noncontact mode TENG is presented. Noncontact mode TENG prevents material wear but generates insufficient power, whereas contact enhances power generation by increasing the charge density on the electrode surface. The proposed device can automatically switch between contact and noncontact modes through a triple-cam mechanism and gear train deceleration mechanism. Experimental results determine the optimal force value of 6 N and corresponding cam height of 1 mm, contact time of 8 min, and noncontact time of 30 min, to ensure good power output and minimal material wear. Simulation results demonstrate that the three cams have more stable mechanical properties and can improve the device's robustness. The cam repose angle and gear train structure are optimized based on the curves of electrical output versus time for both modes, and a method is proposed to extend the self-switching time. The self-switching mode TENG has a longer life than the other two modes, with its transfer charge maintaining 90% of its initial value after 80 h of continuous operation. Herein, a staggered tri-cam self-switching device that can realize mode self-switching between contact and noncontact at very low rotor speed is reported. It can operate in the noncontact mode for a long time and automatically switch to the contact mode after the material surface charge drops to a certain level until the charge is replenished to saturation.image (c) 2023 WILEY-VCH GmbH