Flexible, High-Power Density, Wearable Thermoelectric Nanogenerator and Self-Powered Temperature Sensor

Abstract

We propose a flexible and wearable thermoelectric nanogenerator (FTEG) made from Bi2Te3, which allows high voltage and output power density. The proposed FTEG works as a thermopile with the end-to-end connection of 126 thermoelectric legs, and which is fabricated through magnetron sputtering Cu conductor on polyethylene terephthalate film. Bi, Te, Sb, and Se alloys are used to prepare thermoelectric materials by doping in a fixed proportion and zone melting, and nickel plating on the surface mitigates the deterioration of thermoelectric properties caused by the diffusion of Cu atoms or Cu+ ions. The thermoelectric figure of merit is stable and maintained above 0.7, up to 1.02. More flexibility is allowed by employing double sinusoidal serpentine connecting wires, and no significant property changes are observed even after being folded 200 times. When the temperature difference reaches 50 K, the output voltage of the FTEG will be no less than 520 mV, and the power density will reach 11.14 mW·cm–2. By integration of a low-power, low-threshold voltage boost circuit on the back end of the FTEG, the electronic watch with a liquid crystal display screen can be easily powered to work properly. Furthermore, the FTEG is temperature-sensitive and, thus, can be used for temperature measurement with a resolution of 0.5 K. This work may have important prospects in flexible wearable physical sensors and individualized medical care.

Printable, Highly Sensitive Flexible Temperature Sensors for Human Body Temperature Monitoring: A Review

“…Self-supplied energy has always been the focus of many people's attention [117]. The realization of self-supplied energy by flexible equipment will significantly reduce the equipment's need for external energy, making flexible equipment more portable and more straightforward [118].…”

Flexible 3D Architectured Piezo/Thermoelectric Bimodal Tactile Sensor Array for E‐Skin Application

“…[25][26][27][28][29] However, most reported thin-film TE devices employ in-plane design to build sufficient temperature difference to generate thermopower, [30][31][32][33][34] disagreeing with the thermal gradient orientation of human body, thus renders great challenge to develop flexible TE module with matched thermal impedance for e-skin applications. [35][36][37] Another drawback for the parallel TE device is the long response time due to the long and thin TE leg as heat and current diffusing route. Nevertheless, little achievement has been made on vertical flexible TE device, probably owing to the difficulty in densely building up TE device using organic TE materials with thicknesses exceeding 1 mm.…”

Development of Wearable Temperature Sensor Based on Peltier Thermoelectric Device to Change Human Body Temperature

“…(15) A flexible wearable thermoelectric nanogenerator made from Bi 2 Te 3 was proposed for use in next-generation wearable temperature sensors; this material can be easily incorporated into textiles. (16) A stretchable temperature sensor that removes strain was developed for use in smart healthcare devices. (17) A portable hypothermia device can be used for hypothermia therapy to maintain a low body temperature in pigs and decrease the body temperature via a thermoelectric element included in the pad part.…”