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Electro-conductive (EC) yarns can be woven into a hybrid fabric to enable electrical current to flow through the fabric from one component A to another component B. These hybrid fabrics form the bases of woven e-textiles. However, at the crossing point of an EC yarn in warp and in weft direction, there is a contact resistance and thus generation of heat may occur in this area. Both phenomena are inseparable: if the contact resistance in the EC contact increases, the generated heat will increase as well. Predicting this electrical and thermal behavior of EC contacts in hybrid woven fabrics with stainless steel yarns is possible with a mathematical model based on the behavior of a metal oxide varistor (MOV). This paper will discuss in detail how this can be achieved.

A textile-based energy storage device with electroactive PEDOT:PSS (poly(3,4- ethylenedioxythiophene)/poly(4-styrenesulfonate)) polymer functioning as a solid-state polyelectrolyte has been developed. The device was fabricated on textile fabric with two plies of stainless-steel electroconductive yarn as the electrodes. In this study, cyclic voltammetry and electrochemical impedance analysis were used to investigate ionic and electronic activities in the bulk of PEDOT:PSS and at its interfaces with stainless steel yarn electrodes. The complex behavior of ionic and electronic origins was observed in the interfacial region between the conductive polymer and the electrodes. The migration and diffusion of the ions involved were confirmed by the presence of theWarburg element with a phase shift of 45°(n = 0.5). Two different equivalent circuit models were found by simulating the model with the experimental results: (QR)(QR)(QR) for uncharged and (QR)(QR)(Q(RW)) for charged samples. The analyses also showed that the further the distance between electrodes, the lower the capacitance of the cell. The distribution of polymer on the cell surface also played important role to change the capacitance of the device. The results of this work may lead to a better understanding of the mechanism and how to improve the performance of the device. [ABSTRACT FROM AUTHOR]

The work focused on studying the effect of charging voltage level and the absence of electrode between the measured electrodes on the charge storage profile. The device was applied on a three layered of 5 x 5 cm laminated textile fabric with hydrophobic surface. Stainless steel filament yarns were used as electrodes. As electrolyte, seven layers of the electro-active polymer PEDOT:PSS dispersion was consecutively drop-coated and dried under the temperature of 90-100 °C. During the course of the experiments, the devices were charged and discharged and their response or voltage decay was recorded. The results showed that the higher the charging voltage, the higher the amount of charges stored. The increase in the output voltage was not proportional to the input voltage which means that the device did not behave as either a pure capacitor or a pure battery. The ions movement was confirmed to be involved in the charge-discharge mechanism of the device. [ABSTRACT FROM AUTHOR]

This paper investigates textile-based energy storage devices fabricated with poly(3,4-ethylene dioxythiophene):poly(styrenesulfonate) (PEDOT:PSS) as an electro-active polymer and conductive yarns as the electrodes. The conductive yarns are sewn into a textile substrate and then coated with PEDOT:PSS systematically. Two different sets of devices were made. A comparison of the devices made with silver coated polybenzoxazol filament yarns and the devices made with pure stainless steel filament yarns is performed. The devices were charged and their self-discharge was measured by voltage decay. A study of the influence of charging time on the decay and the effect brought by various load resistors on the voltage decay is also performed. In this research, the devices with electrodes of pure stainless steel filaments yarns performed better than the devices with silver coated yarns; this outcome has been reported as standard by various researchers. [ABSTRACT FROM PUBLISHER]

Smart textiles are fabrics that interact intelligently with nearby surroundings or consumers. The electronic textile (e-textile) can sense environmental circumstances or stimuli and provide information that can effectively respond to and adapt actions. An electrically conductive textile is a piece of smart textile that incorporates conductive fibres, yarns, fabrics, and ultimate products. Conductivity is one of the properties that allow the integration of textiles in electrical circuits to ensure the functionality of electronic devices. The integration of conductive yarns in a structure is a complex and seldom a uniform process as it needs to be ensured that the electrically conductive fabric is comfortable to wear or soft to touch rather than hard and rigid. The paper presents an original method for determining the relationship between the conductivity of conductive textile structures and their elastic characteristics. Statex and Bekinox conductive yarns of fineness 296-610 dtex were used to make woven and knitted structures. The SEM and EDAX analyses of the wires were carried out on the Scanning microscope Quanta FEI 200. The physical-mechanical characteristics analyzed highlighted: strength (N) and elongation at break (%), tear resistance (N), resistance to deformation (kPa) and deformation (mm) of the conductive structures. The modulus of elasticity (N/cm2) and anisotropy was calculated. The correlation coefficients between the three variables have high values (>0.980). The Lloyd material testing equipment coupled with a data acquisition unit-DAQ (white box) was used for the simultaneous variation of elasticity and electrical conductivity of textile structures.