Abstract: A hydrometallurgical and electrochemical process for treating exhausted lead batteries, in particular the active mass and the electrolyte, is described having as products electrolytically obtained lead and elemental sulphur. The active mass (paste) obtained from the mechanical processing of the exhausted batteries, consisting mainly of lead sulphate and dioxide, is dispersed in a dilute H.sub.2 SO.sub.4 solution and then reacted with an Na.sub.2 S solution to convert all the lead compounds present into insoluble lead sulphide and sodium sulphate. After filtration, the sodium sulphate solution is evaporated to obtain the anhydrous salt. From this, by thermal reduction with carbon, the Na.sub.2 S is reformed for use in treating further paste. The lead sulphide obtained in this manner is leached with an electrolyte based on ferric fluoborate, which oxidizes the sulphide to elemental sulphur and solubilizes the lead in the form of fluoborate.