In course of anodic oxidation of lead in chloride–nitrate melt it has been formed β-PbO either in the form of nanopowder with the average size of the particles 20–70nm or in the form of nanofibers with the thickness of 20 nanometers and length 500nm. Synthesis is easily reproduced and can become a basis of industrial production lead nano-oxide. Lead oxide nanopowders and nanofibers tested in a course of potentiodynamic cycling in working conditions of a positive electrode of the acid lead battery, have shown good reproducibility of results and high values of currents density that can be unequivocally connected with increase in the true area of a surface of active mass of electrodes.