A wearable multimodal health monitoring bracelet powered by high-power-density flexible thermoelectric generators

Flexible thermoelectric generators (FTEGs) can harvest energy from the human body to supply energy to wearable electronic devices. Here, we present a long-term health monitoring bracelet integrated with FTEG, an energy management system (EMS), and a health monitoring system (HMS). Based on the optimized nanostructured compound with a composition of Bi 0.5 Sb 1.469 Ga 0.03 Cu 0.002 Te 3.1575 , the bulk-based FTEG achieved a power density of 88.9 μW cm −2 on the surface of the body at an ambient temperature of 17.6°C. Using a low quiescent current consumption switch, an integrated EMS circuit with a high average efficiency of 60.6% and an ultralow self-startup voltage of 20 mV was designed to boost the unstable voltage.