Flexible thermoelectric power generation system based on rigid inorganic bulk materials

Herein, we demonstrate that conventional inorganic materials can be used in wearable systems despite their bulky and rigid nature. In particular, we proposed a bracelet-like modular design of a thermoelectric (TE) module with a heat sink made of rigid inorganic bulk materials. This device is referred to as the flexible TE system (FTES). Experiments and theoretical analyses were performed to verify whether the FTES performs like a conventional TE module even though it is flexible and wearable. In addition, we performed experiments while the FTES was worn on a subject's wrist for body heat harvesting. The FTES produced a usable power output even when the wearer was at rest. When the subject was running at a slow pace, the FTES generated approximately 80 μW. Our analyses indicate that this value can be further enhanced through future design improvements. Nevertheless, based on the experimental and analytical results, the FTES can deliver a usable power output. This research therefore demonstrates the possibility of using high-performance bulk materials in the design of wearable devices.