Abstract
Photo-rechargeable system that combines photovoltaic cells with energy storage devices has the potential to power electronics sustainably without battery replacement. However, current systems suffer from drawbacks such as low efficiency, rigid design, poor stability, and complex fabrication processes. To address these issues, we have created two prototypes of integrated photo-rechargeable systems by combining perovskite solar cells with either zinc-ion batteries or hybrid capacitors, which are designed for powering futural wearable and off-grid electronics, respectively.
In this thesis, we first used a facile inkjet printing and electrodeposition method to fabricate a flexible photo-rechargeable system that combines quasi-solid-state Zn-MnO2 batteries with perovskite solar cells. Due to the highly conductive printed current collector, interdigitated electrode design and the introduction of the protective electrode, the optimised planar battery exhibits ultrahigh volumetric energy and power densities comparable to state-of-the-art micro-batteries or supercapacitors. Consequently, the flexible integrated system achieves ultrafast photocharging within 30 s for emergency electronics with an overall efficiency of 5.28%.
In order to further improve the power conversion ability and to power off-grid electronics with relatively higher power consumption, we developed a highly integrated photo-rechargeable system by combining rigid perovskite solar cells and solid-state zinc-ion hybrid capacitors through a rapid standardised fabrication process. The monolithic design, ionogel electrolyte and precise electrical matching, in conjugation with the high power conversion efficiency of the perovskite solar cells and superior energy storage efficiency of the zinc-ion hybrid capacitors, enable the resultant system with >10% overall efficiency and good cycling stability.
These prototypes demonstrate the feasibility of integrated photo-rechargeable systems for powering various low-power and off-grid electronics. The research on standardised, low-cost, and facile fabrication processes offers a promising path towards industrial fabrication and commercialisation and provides comprehensive academic insights into the next-generation clean energy.