Large-Area Laying of Soft Textile Power Generators for the Realization of Body Heat Harvesting Clothing

This paper presents the realization of a flexible thermoelectric (TE) generator as a textile fabric that converts human body heat into electrical energy for portable, low-power microelectronic products. In this study, an organic non-toxic conductive coating was used to dip rayon wipes into conductive TE fabrics so that the textile took advantage of the TE currents which were parallel to the temperature gradient. To this end, a dyed conductive cloth was first sewn into a TE unit. The TE unit was then sewn into an array to create a temperature difference between the human body and the environment for TE power harvesting. The prototype of the TE fabric consisted of 48 TE units connected by conductive wire over an area of 275 x 205 mm(2), and the TE units were sewn on a T-shirt at the chest area. After fabrication and property tests, a Seebeck coefficient of approximately 20 mu V/K was measured from the TE unit, and 0.979 mV voltage was obtained from the T-shirt with TE textile fabric. Since the voltage was generated at a low temperature gradient environment, the proposed energy solution in actual fabric applications is suitable for future portable microelectronic power devices.