Coupling charge pump and BUCK circuits to efficiently enhance the output performance of triboelectric nanogenerator

Abstract

Triboelectric nanogenerator (TENG) faces significant challenges in practical applications because of its low output charge density and high matching impedance, and the development of its energy management circuits is hindered by high initial device requirements, large circuit size and poor portability. In this work, we propose a simple, efficient and versatile energy management strategy that two-stage amplification of TENG output performance by coupling a charge pump circuit with a BUCK circuit. By implementing the energy management strategy, the charge output per cycle of an ordinary TENG can be increased by more than 40 times, resulting in a power density of 25.2 mWm−2 and a total energy transfer efficiency of exceeding 88% in constant mode. At a working frequency of 1 Hz, the TENG can charge a 1000 μF capacitor to 5.04 V in 240 s and store the energy of more than 12.72 mJ, of which represents an 848-fold increase in stored energy compared to using TENG directly. Remarkably, this TENG device exhibits exceptional an average power of 100.7 μW/Hz, setting a new record for devices with smaller TENG size (< 50 cm2) or limited PM circuit size (< 10 cm2). Moreover, an ordinary TENG can continuously power a wireless sensor by integrating the portable power management circuit, facilitating real-time wireless data transmission. This study is of great significance for the practical application of the TENG power supply in the sensor network of the Internet of Things and for expanding the application range of the TENG.