Researchers are working on flexible batteries that can be printed directly on to fabric. Their research was motivated by the problem of how to power wearable devices. The small gadgets often need significant power sources, but cumbersome battery packs are not an option. The new technique allows the person to literally wear flexible batteries that will power their device.
Nazmul Karim, Knowledge Exchange Fellow at the University of Manchester, who co-authored the research paper on the battery technology says, “It will open up possibilities of making an environmentally friendly and cost-effective smart e-textile that can store energy and monitor human activity and physiological condition at the same time.”
[Image Source: The University of Manchester]
Generally, wearables rely on devices known as supercapacitors to give them charge, supercapacitors act like a battery but also allow for rapid charging that can fully power devices in seconds. The new technology is a solid-state flexible supercapacitor that works by using conductive graphene-oxide ink to print onto cotton fabric. The research on the battery was published in the journal 2D Materials. The paper explains the printed electrodes have very good stability due to the excellent interaction between the ink and textile substrate.
The further development of graphene-oxide printed supercapacitors could lead to wearable technology becoming much more commonplace. The applications for the technology range from it being used in high-performance sportswear that could monitor health and performance to military uses. Clothing that monitors health data for sick patients or those suffering ongoing conditions could also be a use for the groundbreaking technology.
Wearable computers not far off
If the technology is pushed even further the idea of a wearable computer might not be too far off. Dr. Karim explains, "The development of graphene-based flexible textile supercapacitor using a simple and scalable printing technique is a significant step towards realizing multifunctional next generation wearable e-textiles."
Graphene-oxide can be produced at a relatively low cost in a printable ink-like solution. This ink can be applied to cotton textiles to create the supercapacitors which become part of the fabric itself.
Dr. Amor Abdelkader, also co-author of the paper said: "Textiles are some of the most flexible substrates, and for the first time, we printed a stable device that can store energy and be as flexible as cotton. The device is also washable, which makes it practically possible to use it for the future smart clothes. We believe this work will open the door for printing other types of devices on textile using 2D-materials inks."
The printing would likely happen by way of inkjet printers or simple screen printing. Inkjet printing recreates a digital image by propelling droplets of ink onto the textile. This is a very common way of printing and you likely have an inkjet printer in your home or office. The research paper, titled, Inkjet Printing of Graphene Inks for Wearable Electronic Applications explains in its abstract that "Inkjet printing is one of the most promising techniques for the fabrication of wearable electronics due to number of advantages over conventional manufacturing techniques such as digital and additive patterning, reduction in material waste, deposition of controlled amount of materials and compatibility with various substrates."
Perhaps we'll be printing our own flexible batteries in the not too distant future.