A Fully Transient Mechanical Energy Harvester

Here, a novel design of a mechanical energy harvester combining peak power output competitive with state-of-the-art energy harvester devices is reported, but with a design enabling full transience, or dissolution, of the harvester after 30 min upon triggering in basic water. The harvester incorporates a symmetric cell combining LixAl alloy electrodes and polyvinyl alcohol packaging that harvests mechanical energy due to the mechanical-electrochemical stress coupling between the electrodes. Prototype harvester devices demonstrate peak output power of 0.208 mu W cm(-2 )with continuous energy generation up to 1.76 mu J cm(-2) at a mechanical input frequency of 0.1 Hz. This work introduces a new class of power systems simultaneously tailored for transience, high-performance energy harvesting, and operation frequency relevant to wearable technologies.