An energy-saving photo-rechargeable lithium-ion battery based on lead-free hybrid perovskite

The development and utilization of clean energy have emerged as indispensable technologies within contemporary societal structures, and the development of photo-rechargeable lithium-ion batteries (PR-LIB) holds new promise for simultaneously eliminating solar energy volatility limitations and realizing battery self-charging. In this study, we present photoactive electrodes consisting of lead-free bismuth-based hybrid perovskite that combine the dual functions of photovoltaic conversion and energy storage. It was found that the PR-LIB based on this electrode increased the discharge capacity of the battery from 236.0 mA h g⁻¹ in the dark to 282.4 mA h g⁻¹ (a current density of 50 mA g⁻¹) with a growth rate of 19.7% under light conditions. The photogenerated carriers generated by the methylammonium bismuth iodide (MBI) effectively accelerated the charge transfer and lithium-ion diffusion, which contributed to the increase of the capacity and the decrease of the charge-transfer resistance. Furthermore, the charging potential decreased by 0.1 V (6% reduction in input power) while the discharging potential increased by 0.1 V (11.8% increase in output power) under light. This work demonstrates the potential of PR-LIB as an efficient, energy-saving battery in portable electronic devices.