Three-electrode in mono-electrolyte for integrated photo-assisted lithium sulfur battery

The combination of solar cells and rechargeable batteries has been confirmed as a new strategy for the development of solar energy utilization. However, the high charging voltage of Li-ion battery (3.0–4.2 V) and incompatible electrolyte with solar cell is adverse to the combination of photo-assisted rechargeable battery (PRB). In this work, Li–S battery as an energy storage unit is combined with dye-sensitized solar cell to form an integrated three-electrode photo-assisted rechargeable Li–S battery (PRSB). The compatible C/S electrode provides a bridge for realizing the bi-function of photoelectric conversion and storage. In contrast to the dual electrolytes in the previously reported PRBs, lithium bis((trifluoromethyl)sulfonyl)azanide (LiTFSI), namely the highly compatible mono-electrolyte in our newly designed PRSB with three-electrode, facilitates the charge separation and enhances the capacity and stability of integrated photo-assisted rechargeable battery. With the compensation of photogenerated carrier, the charge voltage of PRSB drops 0.12 V and the discharge capacity increases to 885 mAh g−1 under solar charging, indicating that the integrated device is promising to save electric energy and improve the performance of PRBs.