Thermoelectric power generation using nonwoven fabric module impregnated with conducting polymer PEDOT:PSS

[Display omitted] •Thermoelectric element of PEDOT:PSS nonwoven-fabric composites are fabricated.•The composites have high thermal resistance and isotropic electrical conductivity.•Contact resistance at fabric-electrode junctions was significantly reduced.•The thermoelectric power density per PEDOT:PSS content in the fabric are optimized. We report the transport properties of nonwoven fabric-composite thermoelectric (TE) elements impregnated with the polymer poly(3,4-ethylenedioxythiophene):poly(styrene sulfonate) (PEDOT:PSS). The porous structure formed in the fabric after the solvent evaporation of the PEDOT:PSS solution resulted in a high thermal resistance. In addition, the polymer films covering the surface of the fibers in the fabric connected the fibers to form electrical conduction paths, resulting in isotropic electrical conductivity at high PEDOT:PSS concentrations. These two factors provided the optimum PEDOT:PSS concentration for the TE power density per PEDOT:PSS content. Optimizing the TE power density per polymer content could contribute to the low-cost fabrication of TE modules from conducting polymers. We also demonstrated that the flexible TE module fabricated from the nonwoven fabric-composite achieved a power output sufficient to power a light-emitting diode. Contact electrical resistance at polymer-electrode junctions was greatly reduced by the increase in contact area arising from the wavy surface of the fabric composite.