Small-scale energy harvesting through thermoelectric, vibration, and radiofrequency power conversion

TLDR

Sensors are shrinking and integrating, driving demand for autonomous devices that can be powered directly or with a battery. The paper reviews thermoelectric, vibration, and radiofrequency energy harvesting for devices at or below the cubic‑centimeter scale, aiming to enable autonomous sensors powered by environmental energy. The review discusses thermoelectric, vibration, and radiofrequency conversion technologies, covering their operation principles, current state of the art, materials challenges, and recent advances in power conditioning. The authors outline future miniaturization challenges from both materials and device perspectives.

Abstract

As sensors for a wide array of applications continue to shrink and become integrated, increasing attention has been focused on creating autonomous devices with long-lasting power supplies. To achieve this, energy will have to be harvested from the sensors’ environment. An energy harvesting device can power the sensor either directly or in conjunction with a battery. Presented herein is a review of three types of energy harvesting with focus on devices at or below the cm3 scale. The harvesting technologies discussed are based on the conversion of temperature gradients, mechanical vibrations, and radiofrequency waves. Operation principles, current state of the art, and materials issues are presented. In addition, requirements and recent developments in power conditioning for such devices are discussed. Future challenges specific to miniaturization are outlined from both the materials and device perspectives.