A fully enclosed, 3D printed, hybridized nanogenerator with flexible flux concentrator for harvesting diverse human biomechanical energy
Pukar Maharjan, Hyunok Cho, M. Salauddin Rasel, Md. Salauddin, Jae Yeong ParkNano Energy, Aug 17, 2018
Human body motion is highly regarded as a promising source of energy for powering body-worn electronic devices and health monitoring sensors. Transforming the human biomechanical energy into an electrical energy provides a sustainable energy to drive those devices and sensors, reducing their battery dependency. This work presents a fully-enclosed wrist-wearable hybridized electromagnetic-triboelectric nanogenerator (FEHN) for effectively scavenging energy from the low-frequency natural human wrist-motion (≤ 5 Hz). The FEHN incorporates the rolling electrostatic induction and electromagnetic induction using a freely moving magnetic ball inside a hollow circular tube. The materials used in 3D printing technology are used as energy harvesting material for easy, quick and worthwhile fabrication of the FEHN. A thin flexible flux concentrating material is introduced to increase the emf and enhances the electromagnetic output performance. The FEHN can harvest energy under the diverse circumstances and irregular wrist-motions, such as swinging, waving, shaking, etc. Following the experiments, the FEHN achieves an average power density of 0.118 mW cm−3 and can drive a commercial wrist-watch continuously for more than 23 min from just 5 s of wrist motion. This successful demonstration renders an effective approach for scavenging wasted biomechanical energy and provides a promising solution towards the development of sustainable power supply for wearable electronic devices and self-powered healthcare monitoring sensors.