The charging and discharge behavior of an electrically rechargeable alkaline Zn-air battery consisting of a porous Zn/ZnO electrode on the negative side and a porous O-2 electrode on the positive side has been investigated. Galvanostatic experiments have been performed and a one-dimensional numerical model has been developed to analyze these experimental data. The cell voltages, the Zn electrode potentials versus Zn reference, and the O-2 electrode potentials versus Zn reference calculated with this model are in fairly good agreement with the corresponding experimental values. The unwanted redistribution of Zn per cycle is predicted to decrease with increasing cycle number. The numerical model is expected to be useful when optimizing zinc cell designs for specific applications.