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Project "All-FIBRE: All-Fibre Integrated Photovoltaic Storage Device for e-Textiles" funded by FCT, IP.

PTDC/CTM-CTM/1571/2020

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The field of electronic textiles have recently faced a surge of interest due to the possibility of integrating many functionalities such as sensors, for instance temperature and pressure, useful for medical and military monitoring and for fashion. However, the power supply of these electronic devices has been performed by conventional batteries, which besides low durability, are heavy and are difficult to be integrated directly into a textile.

A lightweight and durable energy device able to harvest and store energy, simultaneously, and that can be easily integrated into fabrics, has not yet been developed. Despite some reports of fibre-based energy device developments, few fully integrated energy devices have been explored to date. This project aims to fill this gap and to develop a complete all-fibre integrated photovoltaic-storage device (All-FIBRE device) that can be weaved in a textile enabling solar energy harvesting and storage.

The main motivation to develop fibre solar cells combined with fibre supercapacitors relies on the possibility to obtain and store energy that could be easily integrated into textiles, not stamped, giving the possibility to have electronic textiles that are discreet, breathable, and do not need heavy power energy sources. Since solar photovoltaic energy generationis highly dependent on weather conditions, making solar power intermittent, the use of energy storage devices will support decreasing fluctuations from the generation side andproviding the possibility of performing supplementary services. Moreover, fibre-based devices have the advantage to be directly woven into textiles and fabrics that breathe freely; can accommodate different mechanical deformation by twisting and stretching; and can be easily integrated into different materials that fit the curved surface of the human body.

In conclusion, we propose two innovative concepts using simple, commercially scalable manufacturing processes for high-volume production to fabricate All-FIBRE integrated photovoltaic storage devices able to harvest and store energy to supply common electronic devices (signalization LEDs, emergency communications, or similar electronic devices), while keeping wearable, lightweight and flexibility characteristics.