This paper concerns heat exchange devices with a zigzag configuration containing multi-phase change materials (m-PCMs). A two dimensional mathematical model was established to model the charging behaviour. An experimental system was built to validate the model. The modelling results agree reasonably well with the experimental data for a single PCM, establishing confidence in the model. Extensive modelling was then carried out under different conditions. The results show that the use of m-PCMs intensifies the charging process in comparison with the use of a single PCM. Given other conditions, a larger phase change temperature difference between the m-PCMs gives a more remarkable enhancement of the charging process, and the use of m-PCMs with an unequal mass ratio gives further intensification. The modelling results also show that, for a given input power, an optimal fluid velocity exists for obtaining a high rate of the melting process. (C) 2014 Elsevier Ltd. All rights reserved.