Magnetic ink used to print self-healing devices

Engineers at the University of California, San Diego have developed a magnetic ink proven to be effective in producing self-healing batteries, electrochemical sensors, wearable technology and textile-based electrical circuits.

The ink is made up of microparticles that can both sides of a tear, making them magnetically attached to each side. The ink is different from current self-healing materials; it doesn't require a trigger for activation. It's capable of repairing tears up to three mm.

The microparticles have a magnetic field larger than their own size. The particles are able to conduct electricity at a low cost but have poor electrochemical properties, making their compatibility with sensor devices difficult.

"Our work holds considerable promise for widespread practical applications for long-lasting printed electronic devices," said Joseph Wang, director of the Center for Wearable Sensors and chair of the nanoengineering department at UC San Diego.

The ink has been used to print batteries, electrochemical sensors, wearables and textile-based electrical circuits for testing. In tests, the devices were cut nine times in the same location as well as four times in different locations. In all cases, the devices were able to heal themselves completely while only losing a small amount of conductivity.  

"We wanted to develop a smart system with impressive self-healing abilities with easy-to-find, inexpensive materials," said Amay Bandodkar, a postdoctoral researcher at Northwestern University.