Cambridge University researchers have developed washable, wearable batteries that can be incorporated directly into fabrics.
According to the researchers, such smart fabrics could be used in flexible circuits, healthcare monitoring, and energy conversion applications.
The Cambridge team – in collaboration with China’s Jiangnan University – have shown how graphene and other related materials can be directly incorporated into fabrics to produce charge storage elements such as capacitors.
This could pave way for textile-based power supplies which are washable, flexible and comfortable to wear.
According to the researchers, the new textile electronic devices are based on low-cost, sustainable and scalable dyeing of polyester fabric.
The graphene inks too can be directly coated onto a polyester fabric in a simple dyeing process.
It is the versatility of the process that allows various types of electronic components to be incorporated into the fabric.
Most wearable electronics rely on rigid electronic components mounted on plastic or textiles.
These offer limited compatibility with the skin in many circumstances, are damaged when washed, and are uncomfortable to wear as they are not breathable.
“Other techniques to incorporate electronic components directly into textiles are expensive to produce and usually require toxic solvents, which makes them unsuitable to be worn,” says Dr Felice Torrisi from the Cambridge Graphene Center.
“Our inks are cheap, safe and environmentally-friendly, and can be combined to create electronic circuits by simply overlaying different fabrics made of two-dimensional materials on the fabric.”
The process involves suspending individual graphene sheets in a low boiling point solvent.
This is easily removed after deposition on the fabric, resulting in a thin and uniform conducting network made up of multiple graphene sheets.
The subsequent overlay of several graphene and hexagonal boron nitride (h-BN) fabrics creates an active region, which enables charge storage more or less like a battery.
According to the researchers, the battery fabric is bendable and can withstand washing cycles in a normal washing machine.
Image and content: Felice Torrisi/University of Cambridge