Solar rechargeable redox battery based on polysulfide electrochemistry
A solar rechargeable redox flow battery is presented with the highest reported volumetric and areal energy density for an integrated solar energy harvesting and storage device. These features are demonstrated in a scalable solar rechargeable redox flow battery with iodide/polysulfide as the pair of active materials, nickel foam and platinum mesh permeable porous electrodes and a dye sensitized photoelectrode. The flow rate acts as a controlling mechanism for optimal performance of the device. A charge capacity of 4.17 Ah L-1 together with an energy density of 2.1 Wh L-1 are achieved, which are 6 times larger than previous reported solar redox flow battery chemistries. The solar rechargeable redox flow battery system offers a higher round-trip efficiency and potential cost savings on fabrication compared to coupled separate devices.