High-displacement electret-based energy harvesting system for powering leadless pacemakers from heartbeats

Abstract

In vivo biomedical devices are one of the most studied applications for vibrational energy harvesting. In this paper, we investigated a novel high-displacement device for harvesting heartbeats to power leadless implantable pacemakers. Due to the location peculiarities, certain constraints must be respected for the design of such devices. Indeed, the total dimension of the system must not exceed 5.9 mm to be usable within the leadless pacemakers and it must be able to generate accelerations lower than 0.25 m/s2 at frequencies of less than 50 Hz. The proposed design is an electrostatic system based on a square electret of dimension 4.5 mm. It is based on the Quasi-Concertina structure, which has a very low resonant frequency of 26.02 Hz and a low stiffness of 0.492 N/m, allowing it to be very useful in such an application. Using a Teflon electret charged at 1000 V, the device was able to generate an average power of 10.06 μW at a vibration rate of 0.25 m/s2 at the resonant frequency.

Keywords

• electret-based system
• electrostatic harvester
• energy harvesting
• heartbeats vibration