Potential role of motion for enhancing maximum output energy of triboelectric nanogenerator

Although triboelectric nanogenerator (TENG) has been explored as one of the possiblecandidates for the auxiliary power source of portable and wearable devices, the outputenergy of a TENG is still insufficient to charge the devices with dailymotion.Moreover, the fundamental aspects of the maximum possible energy ofa TENG related with human motion are not understood systematically. Here, we confirmed thepossibility of charging commercialized portable and wearable devices such as smart phonesand smart watches by utilizing the mechanical energy generated by human motion. We confirmed bytheoretical extraction that the maximum possible energy isrelated with specific formfactors of a TENG. Furthermore, we experimentally demonstrated theeffect of human motion in an aspect of the kinetic energy andimpulse using varying velocity and elasticity, and clarified how to improve the maximum possibleenergy of a TENG. This study gives insight into design of a TENG toobtain a large amount of energy in a limited space