Pulse-Charging Energy Storage for Triboelectric Nanogenerator Based on Frequency Modulation
Authors: Kwon-Hyung Lee, Min-Gyun Kim, Woosuk Kang, Hyun-Moon Park, Youngmin Cho, Jeongsoo Hong, Tae-Hee Kim, Seung-Hyeok Kim, Seok-Kyu Cho, Donghyeon Kang, Sang-Woo Kim, Changshin Jo, Sang-Young Lee
Energy harvesting storage hybrid devices have garnered considerable attention as self-rechargeable power sources for wireless and ubiquitous electronics. Triboelectric nanogenerators (TENGs), a common type of energy harvester, generate alternating current-based, irregular short pulses, posing a challenge for storing the generated electrical energy in energy storage systems that typically operate with direct current (DC)-based low-frequency response. In this study, we propose a new strategy that leverages high-frequency response to develop efficient chargeable TENG–supercapacitor (SC) hybrid devices. A high-frequency SC was fabricated using hollow-structured MXene electrode materials, resulting in a twofold increase in the charging efficiency of the hybrid device compared to a control SC made with conventional carbon electrode materials. For a systematic understanding, the electrochemical interplay between the TENGs and SCs was investigated as a function of the frequency characteristics of SCs (fSC) and the output pulse duration of TENGs (ΔtTENG). Increasing the fSC·ΔtTENG enhanced the charging efficiency of the TENG–SC hybrid devices. This study highlights the importance of frequency response design in developing efficient chargeable TENG–SC hybrid devices.
