The team claims their device is “the most efficient on-body energy harvester ever invented” as it has been shown to produce 300 millijoules (mJ) of energy per square centimetre without any mechanical energy input during a 10-hour sleep, as well as an additional 30mJ of energy with a single press of a finger. They believe it could represent “a significant step forward” for self-sustainable wearable electronics.
“Normally, you want maximum return on investment in energy. You don’t want to expend a lot of energy through exercise to get only a little energy back,” said Joseph Wang, the paper’s senior author.
“We wanted to create a device adapted to daily activity that requires almost no energy investment: you can completely forget about the device and go to sleep or do desk work like typing, yet still continue to generate energy. You can call it ‘power from doing nothing.’”
Previous sweat-based energy devices required intense exercise, such as a great deal...