Piezoelectric polymer based acoustic energy harvester for implantable medical devices

Wireless implantable devices (WIDs) have the potential to revolutionize biomedical sensing, but their power supplies face significant challenges. Traditional energy transfer methods such as inductive and RF have limitations due to associated tissue losses. This work demonstrates a promising approach to this problem, using a flexible implantable ultrasound energy harvester (IUEH) made of biocompatible Poly (vinylidene fluoride-co-trifluoro ethylene) (P(VDF-TrFe)) free-standing film. Unlike commonly used piezoceramic devices, IUEH can be fabricated using economical solution processing methods such as spin coating. In addition, the PVDF-TrFE Ultrasound energy harvesters are rarely reported in the literature. The device performance of the polymer IUEH was investigated in air, water, and animal meat tissue, and the results show that it can generate a power output of 1.1 mW cm-2 in meat, and 1.4 mW cm-2 in water at 80 kHz. The device fabricated using a free-standing piezoelectric thin film, offers an optimum output that is comparable to other P(VDF-TrFe) based high-frequency devices. Additionally, its flexible design, lower costs, and biocompatibility make it a promising alternative to lead-based devices; thus, offering safety, affordability, and quick customization, while promoting minimally invasive procedures and driving innovation in medical device development.