The influence of the electrolytic properties of the sulfide-conducting electrolytes CaY 2 S 4 , CaPr 2 S 4 , and BaSm 2 S 4 on the possibility of performing the electrochemical correction of the composition of nonstoichiometric cadmium and lead sulfides is investigated. The width of the homogeneity region of the CdS and PbS sulfides is estimated in the temperature range 300-400 ° C. A model of defect formation is proposed.