| 초록 |
Perfluorosulfonic acid (PFSA) membranes are commercially avaliable for vanadium redox flow batteries (VRFBs) due to their outstanding chemical stability, and proton conductivity. However, high vanadium crossover, and production cost are the limitations for the further commercialization of VRFBs with conventional PFSAs. Here, PFSA membranes were biaxially stretched using constrained deswelling protocol to align the hydrophilic channels in the stretching directions. The stretching ratio of the membranes was controlled by the pre-swelling step, which is followed by annealing process. As the stretching ratio increased, the thickness of the membranes decreased, but vanadium permeability decreased as well. The modified membranes showed higher efficiencies than pristine Nafion 115 in VRFB single cell test. |
