Flexible, Self‐powered Thermoelectric Module for Body‐heat Recovery

Conversion of heat into electrical energy using a thermoelectric generator (TEG) will be beneficial for self‐powered wearable electronic systems. However, the output power of previously reported flexible TE generator (f‐TEG) is too low to meet the requirements of wearable electronic devices. Herein, we report an f‐TEG integrated with inorganic TE materials and exhibiting high output power. The proposed TE device has 60 pairs of p‐type Bi 0.5 Sb 1.5 Te 3 and n‐type Bi 2 Te 2.7 Se 0.3 TE legs, and has an extremely low internal resistance (1.09 Ω). This f‐TEG possesses good flexibility (with a bending radius of ∼1 cm) and high output‐power density (up to 4.49 mW/cm 2 with a temperature difference of 30 K). To convenience use, a step‐up boost voltage converter is integrated with the TEG to convert the low voltage into a high voltage for micro‐device to work, it provides a new candidate scheme for self‐powered wearable electronic devices. Experiments showed that a LED can be lit up by the f‐TEG with a boost circuit. There results demonstrate that the proposed f‐TEG provides ultrahigh output power density and integrated self‐powered devices, can be used to powering low‐power electronics and sensors through heat harvesting.