The transport phenomena of mass and electrical charges play an important role in the proton exchange membrane utilised in fuel cell applications. The calculation of the membrane ion and water transfer is usually determined in two ways: one is a semi-empirical mode that can be experimentally set for any application and cannot be used in the prediction of the characteristics of new cells, and the other is a very complex mathematical approach that needs very long calculation times. In fact, the membrane mass transfer model can cause problems in the management of PEM stack models, by increasing calculation times and, above all, convergence problems. This work attempts to overcome this bottleneck using a novel approach. The validation of the new approach has been made by applying the model results to a PEM fuel cell model and by comparing the overall results to those in the literature. The resulting calculation time warranted the application of this model to a very complex stack simulation, resulting in good fit and reasonable computing times. (C) 2004 Elsevier B.V. All rights reserved.