Impact energy harvesting and storage through duct airflow using magnetostrictive clad films

Abstract

The Internet of Things (IoT) requires power supplies without recharging. We conceived the idea of generating electricity from the impact of magnetostrictive materials against a propeller. This study evaluated the energy harvesting performance and energy storage capabilities of Fe–Co alloy and Ni clad (Fe–Co/Ni) films that directly strike propellers rotated by the wind in a duct airflow. The 0.08- and 0.2-mm-thick Fe–Co/Ni films generated powers of 28.1 and 89.4 µW, respectively. Moreover, the 0.08-mm-thick Fe–Co/No film generated power lower than that generated by the 0.2-mm-thick Fe–Co/Ni film. However, at a wind speed of 1.5 m/s, the 0.08-mm-thick Fe–Co/Ni film generated power, whereas the 0.2-mm-thick Fe–Co/Ni film stopped the rotation of propellers and did not generate any power. Furthermore, the Fe–Co/Ni film was successfully charged in a capacitor, and the stored voltages were 108.3 mV for the 0.08-mm-thick Fe–Co/Ni films for 30 min and 337.3 mV for the 0.2-mm-thick Fe–Co/Ni films for 1 h. It is also worth noting that no damage occurred to the surfaces of the Fe–Co/Ni films.