ABSTRACT
For membrane performance comparison, as shown in Figure 1, a 25 cm2 ZBB cell was used in this work, consisting of a carbon felt (Toyobo, 4 mm), bipolar plate (SGL, 0.6 mm) and membrane (SF600 or Nafion 115). The carbon felt was not used in a zinchalf cell where metallic zinc is plated on the electrode surface during charging (Dennis et al. 2012, Shin et al. 2012). For the experimental preparation, SF600 or Nafion 115 membrane was treated for 5 hours in the distilled water and the aqueous zincbromide solution (2.0 M ZnBr2 electrolyte with 0.5 M ZnCl2) was used with or without 0.7 M Methyl Ethyl Pyrrolidinium (MEP) as a bromine-complexing-agent. The MEP plays a role in preventing the bromine cross over and bromine gasification (Weber et al. 2011). The cell operation was carried out for 30 cycles and the current density was kept constant at 20 mA/cm2. The charge-discharge cycling operation was performed by WBCS3000 (Won-A tech. Korea) with a constant charge time (1 hr) at room temperature (Li et al. 2015).
