Meanwhile, the hydrogen evolution reaction has a reversible potential of approximately -0.83 V vs SHE. So, corrosion reaction is spontaneously favored (∆G = -ve) for the alkaline ZAB. Hence, H2O reacts electrochemically to Zn or itself can undergo electrolysis to form H2 that leads to corrosion product formation. The corrosion of zinc not only consumes Zn, reducing cell capacity, but can also lead to surface passivation the corrosion products reach the zincate saturation concentration. As surface sites are used for the HER process, its change was monitored in O2 and N2 supplied environments. The differences in the formation of H2 is studied using inline gas chromatography (GC) measurements connected to the anode compartment during the discharge of the battery.