After realizing the importance of the operating conditions as discussed above, experiments were designed to determine the minimum achievable fade rate for a DHAQferrocyanide/ferricyanide cell. Cycling tests were performed at OH -concentrations of 1.0, 1.5, and 2.0 M. SOC restriction and regeneration techniques were integrated into cell cycling and operating conditions, such as cutoff voltage of the discharge and regeneration steps, were chosen properly to obtain the lowest fade rate at each of the OH -concentrations. The results are presented in Figure . a) Fade rate vs. OH -concentration under the following conditions: 100% cycling, 0-85% SOC cycling, and 0-85% SOC cycling combined with regeneration. b) Recovery efficiency vs. OH - concentration for the cycling case when 0-85% SOC and the regeneration step are combined. The tests were run for an extended amount of time; the sequence of 0-85% SOC cycling followed by a regeneration step was repeated at least 6 times. Recovery efficiency and fade rates are the averages over the entire test (see SI and Figure for more details). Test conditions: negolyte comprised 7.0 (or 10 ml for the test in 1.5 M OH -) of 0.1 M DHAQ and the posolyte comprised 120 ml of 0.06 M potassium ferrocyanide and 0.03 M potassium ferricyanide. Cell cycling was performed under a constant current density at 50 mA/cm 2 followed by a potentiostatic hold. The cutoff voltage for the charge and discharge steps were 1.4 V and 1.0 V, respectively. Cutoff current densities for the charge and discharge steps were 2 and 1 mA/cm 2 , respectively. For 0-85% SOC restriction step, charging capacity was controlled not to exceed 85% of the total capacity of the cell. Regeneration steps were performed under a constant current density at 10 mA/cm 2 followed by potentiostatic hold at -0.15 V until a cutoff current density of 0.75 mA/cm 2 was reached.