The rising demand for energy storage systems with high power density, rapid charge/discharge capabilities, and long cycle life has pushed extensive research into advanced materials for supercapacitor applications. There are several materials under investigation, and among these materials, conductive polymer composites have emerged as promising candidates due to their unique combination of electrical conductivity, flexibility, and facile synthesis. This review provides a comprehensive analysis of recent advancements in the development and application of conductive polymer composites for supercapacitor applications. The review begins with an overview of the fundamental principles governing electrical conductivity mechanism, applications of conductive polymers and the specific requirements for materials employed for these devices. Subsequently, it delves into the properties of conductive polymers and the challenges associated with their implementation for supercapacitors, highlighting the limitations of pristine conductive polymers and the strategies employed to overcome these drawbacks through composite formation. In this review, conductive polymer composites and their applications on supercapacitors are explored, and their advantages and disadvantages are discussed. Finally, the electromechanical properties of each conductive polymer composite are elaborated.

Modern electronic textiles are moving towards flexible wearable textiles, so-called e-textiles that have micro-electronic elements embedded onto the textile fabric that can be used for varied classes of functionalities. There are different methods of integrating rigid microelectronic components into/onto textiles for the development of smart textiles, which include, but are not limited to, physical, mechanical, and chemical approaches. The integration systems must satisfy being flexible, lightweight, stretchable, and washable to offer a superior usability, comfortability, and non-intrusiveness. Furthermore, the resulting wearable garment needs to be breathable. In this review work, three levels of integration of the microelectronics into/onto the textile structures are discussed, the textile-adapted, the textile-integrated, and the textile-based integration. The textile-integrated and the textile-adapted e-textiles have failed to efficiently meet being flexible and washable. To overcome the above problems, researchers studied the integration of microelectronics into/onto textile at fiber or yarn level applying various mechanisms. Hence, a new method of integration, textile-based, has risen to the challenge due to the flexibility and washability advantages of the ultimate product. In general, the aim of this review is to provide a complete overview of the different interconnection methods of electronic components into/onto textile substrate.

Conductive elastic fabrics are desirable in wearable electronics and related applications. Highly elastic conductive polyamide/lycra knitted fabric was prepared using intrinsically conductive polymer poly (3,4-ethylenedioxythiophene) (PEDOT) blended with polyelectrolyte poly (styrene sulfonate) (PSS) using easily scalable coating and immersion methods. The effects of these two methods of treatments on uniformity, electromechanical property, stretchability, and durability were investigated. Different grades of waterborne polyurethanes (PU) were employed in different concentrations to improve the coating and adhesion of the PEDOT:PSS on the fabric. The immersion method gave better uniform treatment, high conductivity, and durability against stretching and cyclic tension than the coating process. The surface resistance increased from ~ 1.7 and ~ 6.4 Ω/square at 0% PU to ~ 3.7 and ~ 12.6 Ω/square at 50% PU for immersion and coating methods, respectively. The treatment methods as well as the acidic PEDOT:PSS did not affect the mechanical properties of the fabric and the fabric showed high strain at break of ~ 650% and remained conductive until break. Finally, to assess the practical applicability of the treated fabric for wearable e-textiles, the change in surface resistance was assessed by cyclically stretching 10 times at 100% strain and washing in a domestic laundry for 10 cycles. The resistance increased only by a small amount when samples were stretched cyclically at 100% strain, and the samples showed good durability against washing.

Smart hydrogels with high electrical conductivity, which can be a real source of power while also collecting and storing the diverse sources of energy with ultrahigh stretchability, strong self-healability, low-temperature tolerance, and excellent mechanical properties, are great value for tailored wearable cloths. Considerable effort has been dedicated in both scientific and technological developments of electroconductive hydrogels for supercapacitor applications in the past few decades. The key to realize those functionalities depends on the processing of hydrogels with desirable electrochemical properties. The various hydrogel materials with such properties are now emerging and investigated by various scholars. The last decade has witnessed the development of high-performance supercapacitors using hydrogels. Here, in this review, the current status of different hydrogels for the production of flexible supercapacitors has been discussed. The electrochemical properties such as capacitance, energy density and cycling ability has been given attention. Diverse hydrogels, with their composites such as carbon-based hydrogels, cellulose-based hydrogels, conductive-polymer-based hydrogels and other hydrogels with excellent electromechanical properties are summarized. One could argue that hydrogels have played a central, starring role for the assembly of flexible supercapacitors for energy storage applications. This work stresses the importance of producing flexible supercapacitors for wearable clothing applications and the current challenges of hydrogel-based supercapacitors. The results of the review depicted that hydrogels are the next materials for the production of the flexible supercapacitor in a more sustainable way.

Wearable E-textile systems should be comfortable so that highest efficiency of their functionality can be achieved. The development of electronic textiles (functional textiles) as a wearable technology for various applications has intensified the use of flexible wearable functional textiles instead of wearable electronics. However, the wearable functional textiles still bring comfort complications during wear. The purpose of this review paper is to sightsee and recap recent developments in the field of functional textile comfort evaluation systems. For textile-based materials which have close contact to the skin, clothing comfort is a fundamental necessity. In this paper, the effects of functional finishing on the comfort of the textile material were reviewed. A brief review of clothing comfort evaluations for textile fabrics based on subjective and objective techniques was conducted. The reasons behind the necessity for sensory evaluation for smart and functional clothing have been presented. The existing works of literature on comfort evaluation techniques applied to functional fabrics have been reviewed. Statistical and soft computing/artificial intelligence presentations from selected fabric comfort studies were also reviewed. Challenges of smart textiles and its future highlighted. Some experimental results were presented to support the review. From the aforementioned reviews, it is noted that the electronics clothing comfort evaluation of smart/functional fabrics needs more focus.