In only three minutes, this printing method can produce a 10cm x 10cm 'smart textile patch' that is waterproof, stretchable, and integrated with technologies for harvesting energy. At the core of this technological breakthrough are graphene supercapacitors, energy storage devices that are powerful, long-lasting, and can be combined with other power sources such as solar or battery.
To create these e-textiles, the team at RMIT University used laser printing to embed the graphene supercapacitors into the fabric and they have high hopes for their process, with thoughts that the e-textiles could be applied to multiple markets including consumer, defence, and healthcare.
A patent for this new technology is currently pending.
Schematic of the fabrication steps for the laser-printed graphene solar energy storages. Image courtesy of RMIT University.
Current Proof of Concept
In a proof of concept, the RMIT University researchers connected their supercapacitor with a solar cell to deliver an efficient, washable, and self-powering smart fabric that came out ahead of current e-textile technologies.
Dr. Litty Thekkakara, a researcher working on the project, said that smart textiles with inbuilt wireless communications, monitoring technology, and sensors require robust and reliable energy solutions in-order to be commercially viable.
Dr. Litty Thekkakara, RMIT researcher and co-developer, holding smart fabric. Image courtesy of RMIT University.
"Current approaches to smart textile energy storage, like stitching batteries into garments or using e-fibres, can be cumbersome and heavy, and can also have capacity issues," Thekkakara said.
"These electronic components can also suffer short-circuits and mechanical failure when they [meet] sweat or with moisture from the environment. Our graphene-based supercapacitor is not only fully washable, it can store the energy needed to power an intelligent garment—and it can be made in minutes at a large scale. By solving the energy storage-related challenges of e-textiles, we hope to power the next generation of wearable technology and intelligent clothing."
Potential Applications of E-Textiles
The smart fabrics industry is growing and there are plenty of potential applications, particularly in medicine where wearable devices could be used for the monitoring of vital signs, or in defence where the textiles could be used to monitor fatigue or overall 'health status' according to key metrics.
RMIT Honorary Professor, Min Gu, said the technology could enable real-time storage of renewable energies for e-textiles. “It also opens the possibility for faster roll-to-roll fabrication, with the use of advanced laser printing based on multifocal fabrication and machine learning techniques,” Gu said.