Cycle behaviour of hydrogen bromine redox flow battery cells with bromine complexing agents

Bromine complexing agents (BCA) are used to improve the safety of aqueous bromine electrolytes versus outgassing in electrolytes. In this work, cycling performance hydrogen-bromine redox flow battery cells with 1-ethylpyridin-1-ium bromide ([C2Py]Br) as BCA a electrolyte theoretical capacity 179.6 A h L?1 is investigated for first time. The leads increased ohmic overvoltages. One cause drop can be attributed [C2Py]+ cation interaction perfluorosulfonic acid (PFSA) membrane, which results its conductivity. also interacts cell, by forming non-aqueous fused salt second phase exhibits ten times lower conductivity compared electrolyte. steep rise cell voltage at beginning charge curve followed regeneration effect. Electrolyte crossover an accumulation solution and intensifies both adverse processes. Under condition only 30% available under long term cycle conditions. However, high enough compete other technologies.