High power redox flow battery based on CRIII / CRVI redox pair and its mediated regeneration

摘要

The present invention relates to dichromic acid (Cr ₂ ) for use with various fuels (anolytes) in redox flow cells (RFB, also known as reversible fuel cells) that reversibly store electricity as chemical energy. High power, high energy oxidant (catholyte) chemistry based on Cr ^VI as O ₇²⁻ is described. Reduction (discharging) of Cr ₂ O ₇²⁻ to Cr ³⁺ is all investigated solid electrodes that have historically limited the use of Cr ₂ O ₇²⁻ to primary (non-rechargeable) cells such as grenades. It is essentially irreversible in the catalyst. The described invention uses a reversible redox _couple , hereinafter an electron mediator, to donate electrons non-uniformly to the cathode electrocatalyst and uniformly accept electrons from Cr ³⁺ to regenerate Cr ₂ O ₇²⁻ By overcoming this limitation. RFB using this energy and high power density chemical is suitable for low cost energy storage applications ranging from renewable grid level storage to household appliances.