Instead of regular batteries, Redox flow batteries save on weight by storing the charge in the fluid. So, 2 recirculating tanks can be in use charging(solar?) and discharging through a second set of plates at the same time.
ConclusionsIn this work we demonstrated the possibility of storing solarenergy in a simple way using a vanadium redoxflow battery(RFB) and a CdS photoanode; unbiased charged of a solar-RFB (CdS(s)|V3+,VO2+||V3+,V2+|Carbon Felt(s),E0=0.6VNHE) was achieved. A good semiconductor/electrolytematch was achieved allowing the unbiased solar charge ofa RFB up to high state of charge (SOC). CdSe protective overlayer had a twofold increase with photocurrents up to1.4 mA cm2with no external bias. A tandem systembattery using a dye-sensitized solar cell was also studiedto provide necessary photovoltage to charge a standard allvanadium redoxflow (DSC/CdS(s)|VO2+,VO2+||V3+,V2+|Carbon Felt(s),E0=1.2 VNHE); in this configuration, theobserved photocurrent was 1 mA cm2.Given the acidic nature of the electrolytes (pHE0), thephotoanodes are still limited by their long-term stability. Toimprove further the performance of the proposed solar-RFBsystem, the CdS/CdSe junction should be further optimizedto produce more reproducible photoelectrodes displayinghigher photopotentials, currents and stability. Anotheroption is reduced graphene oxide, that have been provenuseful in minimizing CdS photocorrosion. It is antici-pated that new approaches will be proposed and photo-electrodes able to delivery higher current densities andphotopotentials will be soon available. For example, organicalkaline electrolytes are currently being tested that allowthe use of stable semiconductors such as hematite
Unbiased solar energy storage: Photoelectrochemical redox flow battery. Available from: https://www.researchgate.net/publication/295539790_Unbiased_solar_energy_storage_Photoelectrochemical_redox_flow_battery [accessed May 01 2018].
A solar rechargeable redox flow cell
The present invention relates to a solar rechargeable redox flow cell, a method for storing solar energy by chemicals conversion through the solar rechargeable redox flow cell, an electrochemical system comprising the solar rechargeable redox flow cell and a method of operating the electrochemical system. The invention allows for direct conversion of sunlight into chemicals production that can be stored and used as fuel in a redox flow battery.