"A lead-acid battery comprising at least one pari of positive and negative plates immersed in an electrolyte both comprising sulfuric acid and a chalcogen-containing compound soluble in said bath and having the empirical formula ##STR4## wherein X is a chalcogen, each of R1 and R2 is selected from hydrogen, NR3 R4 and R5, at least one of R1 and R2 is other than hydrogen, each of R3 and R4 is select" . . . . . . .