Self-powered energy conversion and energy storage system based on triboelectric nanogenerator

Abstract

As two most crucial technologies in today's renewable energy system, energy conversion and energy storage are usually achieved by different and independent devices. Herein, two novel self-powered units are integrated to achieve the above two goals through the coupling between recently invented triboelectric nanogenerator (TENG) and different electrical appliances. In the first unit, large scale and uniform nanofibers prepared through electrospinning, which is totally driven by a rotatory TENG based on lateral sliding mode, are directly utilized as the electrode materials for flexible supercapacitors (SCs), constructing self-powered energy conversion (SP-EC). As an energy storage device, this as-fabricated SC is further charged directly by an arch-shaped TENG with vertical contact-separation mode, which realizes self-powered energy storage (SP-ES). In addition, several TENG cells can be integrated together to fully charge SCs connected in series, which are capable to drive different devices on account to the tunable operating voltage benefiting from the flexible numbers of TENG cells and SCs. Given the fact that the TENG can harvest kinetic energies from environment to generate electricity directly, without any extra power supply, this SP-EC and SP-ES system contributes to energy conservation in the entire lifetime of SCs.