Abstract
Previous model calculations of the superconducting properties of aggregates of superconducting grains coupled by Josephson tunnel barriers did not take into account the charging energy associated with small metal grains. It is pointed out that in granular superconductors, in which the grain size is 20-100 Å, the charging energy can be orders of magnitude larger than the Josephson coupling energy and superconducting coupling between the grains is quenched unless the grains are in intimate electrical contact.