A dynamic model of a discrete reversible fuel cell (RFC) system has been developed in a Matlab Simulink® environment. The model incorporates first principles dynamic component models of a proton exchange membrane (PEM) fuel cell, a PEM electrolyzer, a metal hydride hydrogen storage tank, and a cooling system radiator, as well as empirical models of balance of plant components. Dynamic simulations show unique charging and discharging control issues and highlight factors contributing to overall system efficiency. © 2008 Elsevier B.V. All rights reserved.