An intrinsically stretchable power-source system for bioelectronics

Soft, stretchable electronics, feasible for wear and implantation in the human body, face the challenge of power supply. A promising approach is scavenging energy from body motions, necessitating mechanical-energy-harvesting devices that can stretch with the human body. However, existing stretchable designs have much higher stiffness than biotissues and lack stretchable circuits for power regulation. Here, we report a fully stretchable, integrated power source, consisting of a triboelectric nanogenerator (TENG), a polymeric four-transistor-based rectifier, and a supercapacitor, that harvests energy from body motions. Guided by rational design and built from ultrasoft elastomers, the TENG achieves tissue-like modulus, high stretchability, and high-output power, which we demonstrated in an implantable harvester on a porcine heart. We also demonstrate that the fully integrated power source, as the first of its kind, can operate conformably on the human body and serve as a sustainable power source for wearable and implantable electronic systems.