Textile-based Joule heaters in combination with multifunctional materials, fabrication tactics, and optimized designs have changed the paradigm of futuristic intelligent clothing systems, particularly in the automobile field. In the design of heating systems integrated into a car seat, conductive coatings via 3D printing are expected to have further benefits over conventional rigid electrical elements such as a tailored shape and increased comfort, feasibility, stretchability, and compactness. In this regard, we report on a novel heating technique for car seat fabrics based on the use of smart conductive coatings. For easier processes and integration, an extrusion 3D printer is employed to achieve multilayered thin films coated on the surface of the fabric substrate. The developed heater device consists of two principal copper electrodes (so-called power buses) and three identical heating resistors made of carbon composites. Connections between the copper power bus and the carbon resistors are made by means of sub-divide the electrodes, which is critical for electrical–thermal coupling. Finite element models (FEM) are developed to predict the heating behavior of the tested substrates under different designs. It is pointed out that the most optimized design solves important drawbacks of the initial design in terms of temperature regularity and overheating. Full characterizations of the electrical and thermal properties, together with morphological analyses via SEM images, are conducted on different coated samples, making it possible to identify the relevant physical parameters of the materials as well as confirm the printing quality. It is discovered through a combination of FEM and experimental evaluations that the printed coating patterns have a crucial impact on the energy conversion and heating performance. Our first prototype, thanks to many design optimizations, entirely meets the specifications required by the automobile industry. Accordingly, multifunctional materials together with printing technology could offer an efficient heating method for the smart textile industry with significantly improved comfort for both the designer and user.

Intelligent textiles are predicted to see a surprising development in the future. The consequence of this revived interest has been the growth of automobile industry and the improvement of innovative methods for the incorporation of electrical and thermal features into textiles materials. In the present work, the development of a smart stretchable heating device integrated into a car-seat headrest has been identified as a target application. The need for smart conductive materials is becoming increasingly apparent, but they still represent a great challenge for the heating textile area, particularly in additive manufacturing. Polymer-based composites reinforced with copper and carbon powders, attractive as advanced coatings, seems to be good solutions to this issue. Such composites are now acquainted as ideal materials for electronic device engineering and fabrication, thanks to their excellent electrical and thermal conductivities while maintaining suitable mechanical compliance. For easier process and integration, an extrusion 3D printer is employed to achieve thin films coated on the surface of the textile substrate. The developed heater device consists of two principal copper electrodes (so-called power bus), and one heating resistor made of carbon composites designed in different configurations. Finite element models (FEM) are developed to predict the heating behavior of the tested fabric substrates under different pattern suggestions. Experimental measurements via a thermal camera are in consistent with the numerical solutions. It is pointed out that the design optimization based on an adequate tuning of the pattern’s parameters allows to solve inevitable matters in terms of temperature regularity and overheating effect.