The paper presents a comparison of the models currently used in relation to the available experimental data. The review highlights the main causes of discrepancies between the results of modeling and experimental data. The models are based on factors that have no physical interpretation and are used only as "fitting parameters". This hampers use of these models in simulations on states other than those that prevailed during the experiments for which the coefficients were determined. (C) 2019 Hydrogen Energy Publications LLC. Published by Elsevier Ltd. All rights reserved.