Corrosion of the metal bipolar plates of a proton exchange membrane fuel cell is one of the fundamental problems faced by systems of this type and affects its short-term losses and long-term degradation and eventual failure. Passivation is a two-sided problem, which in one sense means protecting the bipolar plate from further corrosion, but at the same time increases the ohmic losses, due to which the fuel cell achieves worse performance characteristics. The assignment theoretically presents the possible choice of corrosion-resistant materials for bipolar plates and the loss mechanisms and degradation theories related to the bipolar plates themselves and to the interconnection of component degradation (Fenton's mechanism). Using II. Generation of point defect model (PDM-II), the task is to develop a 1D + 1D model of passivation and corrosion of iron bipolar plates, through which we can observe the thermodynamically consistent development of the passive layer on the cathode and the losses associated with it, and analyze the contamination of the electrolyte through the dissolution of the passive layer and, in the absence of the passive layer, predict corrosion operation (in the paper such a case occurs at the anode). We observe the key influence of the acidic environment on the development of corrosion and analyze the parameters of the governing equation. The paper proposes further development of the model for application on alloys and on metals covered with a coating layer for bipolar plates.
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