Alkaline electrochemical cells containing no added mercury and having a concentration of potassium hydroxide in the electrolyte, prior to discharge, of between about 34 and 37% (w/w solution) and wherein the amount of electrolyte is such that, after a calculated level of one electron discharge of the manganese dioxide, the calculated concentration of potassium hydroxide is between 49.5 and 51.5% (w/w solution), have superior performance in intermittent discharge tests.