A nonlinear electrical circuit dynamic model for different fuel cells is provided. The model provides a nonlinear electrical circuit equivalent, the parameters of which correspond to the particular fuel cell being modeled. The parameters can be theoretically or experimentally derived from the responses of the particular fuel cell. The resulting model can have impedances that are equivalent to that of the particular fuel cell, thereby capturing or providing a good approximation of the transient behavior of the particular fuel cell. More particularly, the resulting model can have impedances in the low frequency range less than 100 Hz that are equivalent to that of the particular fuel cell.