Conductive tracks are key constituents of wearable electronics and e-textiles, as they form the interconnective links between wearable electrical devices/systems. They are made by coating or printing conductive patterns or tracks on textiles or by weaving, knitting, or embroidering conductive yarns into textiles. Screen printing is a mature and cost-effective fabrication method that is used in the textile industry. It allows a high degree of geometric freedom for the design of conductive patterns or tracks. Current screen-printed conductive textiles have the limitations of low durability when washed or when placed under bending, and they typically require encapsulation layers to protect the printed conductor. This paper presents a printable paste formulation and fabrication process based on screen printing for achieving a flexible and durable conductive polyester-cotton textile using an inexpensive carbon as the conductor. The process does not require an interface, the smoothing of the textile, or an encapsulation layer to protect the conductor on the textile. A resistivity of 4 × 10⁻² Ω·m was achieved. The textile remains conductive after 20 standard washes, resulting in the conductor’s resistance increasing by 140%. The conductive textile demonstrated less than ±10% resistance variation after bending for 2000 cycles.

Textile supercapacitors are a key enabler of future, wireless, textile based smart wearables. With high power densities and long cycle lives, textile supercapacitors can be readily paired with energy harvesters to power the wearable technology. However, the energy density of these devices remains low (of the order of μ Wh) and work to increase this through improvements in the electrode design are requiring ever more complex materials and manufacturing processes. This work presents a novel and safe organic electrolyte that can increase the energy density of a simple symmetric activated carbon textile supercapacitor by ∼8 times when compared to previous devices utilizing an identical substrate and set of electrodes. With a capacitance of 34.0 mF.cm ⁻² and an energy density of 18.9 μ Wh.cm ⁻² , this device showed excellent performance. The device also underwent a rarely seen test for calendar ageing and was found to still exhibit 48% capacitance retention after two months of calendar ageing. This novel electrolyte enables the production of high energy density electric double layer textile supercapacitors without the need for pseudocapacitve or battery-like electrode materials.

This paper presents a universal fabrication process for single-layer textile supercapacitors, independent of textile properties such as weave pattern, thickness and material. To achieve this, an engineered copolymer membrane was fabricated within these textiles with an automated screen printing, phase inversion and vacuum curing process. This membrane, together with the textile yarns, acts as a porous, flexible and mechanically durable separator. This process was applied to four textiles, including polyester, two polyester-cottons and silk. Carbon-based electrodes were subsequently deposited onto both sides of the textile to form the textile supercapacitors. These supercapacitors achieved a range of areal capacitances between 3.12 and 38.2 mF·cm⁻², with energy densities between 0.279 and 0.681 mWh·cm⁻³ with average power densities of between 0.334 and 0.32 W·cm⁻³. This novel membrane facilitates the use of thinner textiles for single-layered textile supercapacitors without significantly sacrificing electrochemical performance and will enable future high energy density textile energy storage, from supercapacitors to batteries.