The CO2 evolution is significantly lower during the next cycles and the distribution over the cycling profile is different, so most of the carbonate impurities are consumed during the first cycle. The CO2 evolved in the consecutive cycles is produced through other reactions, like the oxidation of the electrolyte or the conductive carbon . Three separate CO2 peaks are formed in both electrolytes, a smaller one at low potentials (3.3 V) and two overlapping at high potentials of 4.15 V and 4.25 V.