Advanced designs for electrochemically storing energy from triboelectric nanogenerators

Coupling an electrochemical energy storage system (EES) to triboelectric nanogenerators (TENGs) as the self-charging power cell (SCPC) enables critical enhancement in energy conversion and utilization, therefore attracting excitement in the area of low-cost and sustainable energy technology research. Rather than discussing TENG metrics, this review describes the advancement of SCPCs conforming to different EESs, including supercapacitor (SC), metal-ion battery (MIB), and metal-air battery (MAB). In view of the main challenges of SCPCs, solutions regarding (1) building a direct current (DC)-based triboelectric energy harvesting system, (2) applying a high-efficiency and commercial power management circuit (PMC), (3) developing low self-discharge current and new energy storage systems, (4) proposing ingenious structure- and performance-matching design, and (5) exploring frontier application scenarios are presented in detail, with the expectation of highlighting the significance of SCPC technology in power source-free circumstances and providing a forward-looking guideline for the future development and application of self-charging energy storage systems.