Dual Mode Rotary Triboelectric Nanogenerator for Collecting Kinetic Energy from Bicycle Brake

Regenerative braking system is a promising technology for electrical vehicles, in which the excess kinetic energy can be effectively collected and utilized. As a new energy technology based on contact electrification, triboelectric nanogenerator (TENG) is suitable for harvesting dissipated kinetic energy in braking systems. Herein, a dual mode rotary TENG (DMR‐TENG) is reported, which is installed on the bicycle disc brake for collecting kinetic energy in riding mode and braking mode. First, the electric generation mechanism of DMR‐TENG is analyzed and then the characteristics in different structural and kinematic parameters by simulation and experiment are investigated. Furthermore, a linkage mechanism is designed for two modes switching by controlling the distance between two triboelectric layers of the DMR‐TENG. The results illustrate that the DMR‐TENG can simultaneously illuminate 156 serial LEDs as a warning signal while riding and braking. In addition, it can charge a 300 μF capacitor and act as a power source to drive a speedometer, which can measure the bicycle speed in real time. Herein, a considerable prospect in vehicle kinetic energy collecting is demonstrated and may have potential application in intelligent transportation.