Bio-inspired high-performance belt-flex thermoelectric generators with Quasi–Archimedean spiral structures

The construction of high-density thermoelectric legs on flexible thermoelectric generators (F-TEG) to enhance thermal energy utilization has garnered widespread attention. However, designing an efficient spatial structure to increase the density of TE legs in F-TEG remains challenging. Inspired by the spiral configuration of nautilus shells, we have developed a novel belt-shaped flexible thermoelectric generator (BF-TEG) featuring a spiral multi-layered three-dimensional structure. This multi-layer structure not only increases the number of TE legs along the thermal gradient but also mitigates rapid heat transfer to the cold end, enabling high-performance output from the device. The BF-TEG exhibits an ultrahigh normalized Seebeck voltage of 0.518 mV/K cm −2 at a 40 K ΔT, which is double that of the state-of-the-art printed thin-film devices. Electricity can be generated directly without the need for a spacer in actual wear. Demonstrations of it powering electrochromic devices and LED bulbs show its potential as an energy supply device.