Effect of Membrane on the Performance of a Hydrogen-Vanadium Regenerative Fuel Cell

Hydrogen-vanadium regenerative fuel cells offer a feasible solution for storing electrical energy from the grid or directly from renewable energy sources such as wind and solar. Due to the relatively high cost of vanadium ($ per kg), the hydrogen-vanadium flow battery is attractive over the all-vanadium system due to the 50% reduction in the amount of vanadium solution required. Furthermore, by replacing the negative vanadium electrode with a hydrogen electrode the effect of self-discharge by the crossover of unwanted ions, mostly the smaller vanadium II and III ions, is expected to be greatly reduced. Also, by having a two-phase system, gaseous negative electrode and aqueous positive electrode, crossover species can be easily separated and recovered. In this presentation, the performance of electrospun perfluorosulfonic acid (PFSA)/polyphenylsulfone and PFSA/polyvinylidene fluoride (PVDF) composite membranes, relative to PFSA membranes such as Nafion, with regards to the self-discharge rate and electrical performance of a hydrogen-vanadium regenerative fuel cell will be discussed.