Photo-assisted (de)lithiation to enhance photoelectrochemical storage in quasi-solid-state Li-ion batteries†

The development of photo-assisted rechargeable batteries is an attractive approach to realize the conversion and storage of solar energy in a single device, but designing bifunctional electrodes and improving their safety are challenging. Herein, we chose CsPbBr₃ perovskites as the photo-responsive unit and lead phytate as the ion storage unit for the construction of a dual-functional cathode. The designed photo-cathode possessed enhanced photon responsiveness to benefit solar conversion and reversible redox centers for direct energy storage. Moreover, considering the safety of photo-assisted Li-ion batteries (PA-LIBs), a polymer-based electrolyte was used instead of a traditional liquid-based electrolyte to further restrict leakage and decomposition issues. During the photo-assisted charging and discharging processes (AM 1.5 G, 100 mW cm⁻²), the specific capacity of the assembled quasi-solid-state PA-LIB increased by 11.4% and 64.8%, respectively, compared with conventional electric charging and discharging, thus providing an efficient and sustainable strategy to realize solar-driven electrochemical energy storage.