Achievements and Prospects of Thermoelectric and Hybrid Energy Harvesters for Wearable Electronic Applications

Abstract

Wearable electronics are of great interest and have the potential to play important role in next-generation electronics. The human body is an endless and stable source of thermal radiation energy. Thermoelectric generators (TEGs) are promising devices to scavenge thermal energy from human body and directly convert this low-grade heat into electricity to power low-power wearable electronics and eliminate the need for replacement and management of the batteries. TEG’s performance is mainly dependent on the material properties and temperature difference across thermoelectric (TE) materials. For wearable applications, mechanical flexibility is also important. This chapter reviews the development of organic and nanocomposite TE materials, inorganic TE materials with flexible supporting substrate, and self-supporting flexible inorganic TEGs without substrates. Structural design can enhance the temperature difference across TE material, and the use of hybrid energy-harvesting technology to further enhance the efficiency of energy conversion is described.