A wearable energy-harvesting device could generate energy from the swing of an arm while walking or jogging, say researchers.
The device, about the size of a wristwatch, produces enough power to run a personal health monitoring system, reported the team from Pennsylvania State University and the University of Utah.
"The devices we make using our optimised materials run somewhere between 5 and 50 times better than anything else that's been reported," said Susan Trolier-McKinstry, the Steward S. Flaschen Professor of Materials Science and Engineering and Electrical Engineering from Penn State.
Energy-harvesting devices are in high demand to power the millions of devices that make up the Internet of Things (IoT).
By providing continuous power to a rechargeable battery or supercapacitor, energy harvesters can reduce the labour cost of changing out batteries when they fail and keep dead batteries out of landfills.
According to the researchers, they can double the power output using the cold sintering process - a low-temperature synthesis technology developed at Penn State.
In addition, the researchers are working on adding a magnetic component to the current mechanical harvester to scavenge energy over a larger portion of the day when there is no physical activity, said the study published in the journal Advanced Functional Materials.