Ubiquitous magneto-mechano-electric generator

Abstract

Stray magnetic field considered as harmful noise for the human body can be a ubiquitous energy source. We are surrounded with 50/60 Hz parasitic magnetic noise arising from power delivery infrastructure, but it cannot be readily utilized by traditional electromagnetic harvesters. Here, we introduce a novel magnetomechano- electric (MME) generator with a colossal power density that can turn on 35 LEDs and drive a wireless sensor network under a weak magnetic field of 5-7 x 10(-4) T at a low frequency of 60 Hz. The MME generator is a cantilever structured magnetoelectric (ME) laminate composite in which the < 011 > oriented anisotropic single crystal fiber composite (SFC) is bonded to Ni plate and Nd permanent magnet proof mass. The ME laminate composite has a strong ME coupling (alpha(ME) similar to 160 V cm(-1) Oe(-1)) even without magnetic bias due to the intrinsic property of Ni. The MME generator is also found to exhibit a colossal output power density of 46 mW cm(-3) Oe(-2) under a weak magnetic field of 1.6 x 10(-4) T at 60 Hz. This MME generator can be a ubiquitous power source for wireless sensor networks, low power electric devices, and wireless charging systems by harvesting tiny amounts of parasitic magnetic energy from our living environment.