Biodegradable Battery

Over the past few years, materials scientists have developed super-thin silicon chips that dissolve safely in the body. Such microchips could be used in medical implants that disintegrate once they’re no longer useful, rather than being surgically removed. Powering these devices has been tricky, but researchers have created a neat solution: a completely biodegradable battery. The miniature power pack contains metals like magnesium that dissolve in the body and whose ions, which are released in the process, are non-toxic in low concentrations. Pictured is a four-cell battery (top left) breaking down in water over three weeks until it’s completely dissolved (bottom right). With a few improvements, the researchers suggest, a one-micrometer thick, 0.25cm² single-cell battery – roughly the size of a pinhead but much thinner – could power a wireless implantable device for a day or more. If so, doctors might one day deploy self-powered devices that deliver therapies and then vanish.

Written by Daniel Cossins

Daniel Cossins

Writer

As a freelance science writer, Dan's work has been published in award-winning magazines including BBC Focus, Wired UK, Cosmos, BBC Knowledge, BBC History and Men's Health.

Website

• Image courtesy of John Rogers and colleagues
• University of Illinois at Urbana-Champaign, USA
• Adapted by permission from Macmillan Publishers Ltd: Nature 2014
• Research published in Advanced Materials, February 2014