Fig. 3

Averaged cell potentials of 30 discharge steps (bottom; red color) and 30 charge steps (top; orange color) for five as-prepared zinc oxygen batteries cycled at 2.0 mA cm⁻² and limited to 3% of the theoretical capacity. The cell potential only deviates marginally between the batteries. Here, a Zn sponge with anion exchange ionomer (AEI) was used as the anode¹¹ and a Sr₂CoO₃Cl-GDE was used as the cathode¹¹ for all batteries. The standard deviation in percent between the averaged cell potentials of each cell is given during charge and discharge. The errors bars indicate the standard deviation in cell potential during the course of cycling for each cell individually.