Abstract：The physicochemical processes in zinc-air fuel cells can be represented by an equivalent circuit model. However, the impedance distribution of anode and cathode is not taken accounted in the existing models. A whole cell model including the anode and cathode impedances is presented and a simplified version is developed that neglects the effect of the anode. The influences of the cell structure, performance degradation, storage condition, conductive agent in the zinc anode, and structural changes in the air cathode on the impedance are investigated with the model fitting experimental data with chi-square test results all less than 0.01. The impedances predicted by the model are then used to analyze the impedance change mechanism. The results show that this model can be used to study metal-air batteries.
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