Recent advances in triboelectric nanogenerator based self-charging power systems

Over the last few decades, tremendous efforts have been focused on developing high performance energy storage systems such as batteries and supercapacitors for the applications in portable devices. However, limited lifetime of these storage systems is still a crucial challenge, meaning inconvenient recharging or replacement is inevitable. Since 2012, a novel technology of triboelectric nanogenerator (TENG) has been proposed for converting tiny mechanical energy into electricity, and various breakthroughs have been achieved for self-powered systems. Integrating TENG with energy storage devices could be a promising way to provide sustainable power supply for long-term operations. In this review article, we present the recent advances in the TENG-based self-charging power systems (SCPSs), which will have significant applications in internet of things, portable electronics, and wearable electronics. Hybrid SCPSs combining other energy conversion technologies are also included. The key approaches for improving the total efficiency of the SCPSs are systematically summarized. Finally, some of the important challenges and future directions to be pursued are also highlighted.