Smіrnova O. The mass-transfer processes in the anode-membrane system of fuel cell

Fuel cell anode-membrane unit (AMU) consisting of the active layer - platinized graphite, pressed to protonconductive membrane. Determine the influence of mass transfer on the rate of electrooxidation of hydrogen in the anode-membrane of the fuel cell. Potentiostatic and galvanostatic polarization techniques, the method of cyclic voltammetry with linear scan of the current and potential, electron microscopy and EDX analysis, electrochemical impedance, computer simulation. The area of the hydrogen reaction ionization in a stationary mass transfer process was defined, which deepens the distribution patterns understanding of local current generation rate within the AMU and develops the theory of porous hydrophobized electrodes. The relationship between the active layer thickness of AMU and hydrogen humidity was found, allowing to choose the optimal active layer design and formulate requirements for admissible fluctuations interval and process change rate of parameters and predict the occurrence of critical phenomena in AMU of fuel cells. For the first time the critical phenomena in the active layer and the self-oscillation potential in the process of energy generation were substantiated and the mathematical models of predicting the occurrence of flooding and dehydration phenomena of the active layer of AMU were developed. The results of the thesis are recommended for use in the design of fuel cells with solid polymer electrolyte membrane and in formulating the control algorithm of their working regime. The results of the thesis are recommended for the use in the design of optimal construction of fuel cells with hard-polymeric electrolyte and membrane systems of electrolysis, and to make the algorithm of their operational modes control. The results of the thesis solve the task of defining characteristic peculiarities of mass transfer processes at hydrogen ionization reaction in the anode-membrane unit of fuel cell and they are essential in the development and fuel cells producing.