With the aim of improving the electrochemical properties of this candidate cathodic material for lithium ion batteries, a vanadium oxide (V2O5) and polypyrrole (Ppy) hybrid was prepared using pyridinesulfonic acid (PSA) as additive. The hybrid synthesis has been carried out in the literature by chemical polymerization of pyrrole in the host inorganic matrix, using the V2O5 dispersed in an acidic solution as an oxidizing agent. In this work the hybrid has been synthesised with PSA giving good results compared to other samples of the pristine V2O5 and to the Ppy/V2O5 hybrid without additive. An improvement of about 20% in the charge storage capacity has been achieved. The reasons for this improvement are discussed and analyzed using different experimental techniques. The hybrid material has the added advantage of an improved performance without the addition of any binder or conducting element as a cathode in a lithium ion battery. (c) 2007 Elsevier B.V. All rights reserved.