The current voltage plot of PEM fuel cell with long feed channels

The formula for voltage loss on the cathode side of the polymer electrolyte membrane fuel cell (PEMFC) is derived, taking into account oxygen consumption in the feed channel. Limiting current density due to the oxygen exhaustion along the channel is obtained. Theory predictions are in line with experiments that were performed to test the theory. The results reveal new reserves for the optimization of the cell performance. They also show new in situ electroanalytical options: the study of electrochemical reaction in the catalyst layer via the cell voltage¯current plots and via detecting of the feed gas consumption or local current distribution along channel.