Screen Printed Flexible Water Activated Battery on Woven Cotton Textile as a Power Supply for E-Textile Applications

Electronic textiles (e-textiles) development has been attracting significant research interest over the past two decades, especially in the field of wearable electronics. Fabric based flexible batteries are an attractive solution to the challenge of powering e-textiles. This work presents a simple and scalable textile primary battery, produced via a low-cost screen-printing manufacturing process. The device architecture is purposefully simple, based on a standard aluminum-silver redox reaction and a salt bridge. The battery as manufactured is inactive and requires the addition of water to be activated, and it can therefore be classified as a reserve battery. The battery is suitable for long-term storage, having negligible self-discharge rates. Initial batteries achieved a total area capacity of <inline-formula> <tex-math notation="LaTeX">$101.6~\mu $ </tex-math></inline-formula>Ah/cm² and an energy density of 2.178 mWh/cm³ above 0.8 V. Further refinements of the battery include the inclusion of a novel membrane separator within the woven cotton textile layer and blending the metal salts with polyvinyl alcohol to reduce the number of textile layers. This optimization resulted in an improved performance of <inline-formula> <tex-math notation="LaTeX">$166.8~\mu $ </tex-math></inline-formula>Ah/cm² in area capacity and 3.686 mWh/cm³ in energy density above 0.8 V. This work has demonstrated the feasibility of an aluminum-silver reserve textile battery and demonstrates a novel method for printing a phase inversion membrane separator into the textile. Following an encapsulation process, this flexible textile battery can be easily integrated into a standard woven textile, providing a robust, lightweight and flexible power supply.