Application driven design, fabrication and characterization of piezoelectric energy scavenger for cardiac pacemakers

We will present an approach that can be used for the powering of miniaturized and autonomous leadless implants, which could be directly placed inside a human heart. We will discuss the energy content of the heart vibration spectrum in a view of energy harvesting. We will demonstrate, that according to the heart beat acceleration spectrum obtained by placing accelerometers inside several heart cavities, the useful vibration energy is localized at lower frequencies (15 to 30 Hz). We will also detail the dimensional restrictions in the case of a leadless pacemaker. Since it has to be placed into a heart through veins, the device is expected to be of cylindrical shape with a diameter not exceeding 6 mm. We will present an application driven design of a resonant piezoelectric energy scavenger aiming at powering a leadless pacemaker with a useable energy of few micro Joules per a heartbeat.