Vehicle applications require efficient cold start ability and durability of polymer electrolyte membrane fuel cells (PEMFCs). In this study, various self-cold start strategies including purging the PEMFC at shutdown and using galvanostatic operation at startup are proposed. The cold start characteristics from −5 • C of a single cell are experimentally investigated in situ on a laboratory scale. The amount of cumulated charge transfer density, corresponding to the amount of product water, is used as an index to quantify the cold start capability. Gas purge at shutdown before freeze is found to facilitate the PEMFC cold start, although the improvement is relatively small compared with other methods such as gradually increasing the current during startup. Microscopic studies of the membrane electrode assembly (MEA) after cold start failure are conducted to determine material degradation due to ice formation.

Fuel starvation is a major cause of anode corrosion in low temperature polymer electrolyte fuel cells. The fuel cell start-up is a critical step, as hydrogen may not yet be evenly distributed in the active area, leading to local starvation. The present work investigates the hydrogen distribution and risk for starvation during start-up and after nitrogen purge by extending an existing computational fluid dynamic model to capture transient behavior. The results of the numerical model are compared with detailed experimental analysis on a 25 cm2 triple serpentine flow field with good agreement in all aspects and a required time step size of 1 s. This is two to three orders of magnitude larger than the time steps used by other works, resulting in reasonably quick calculation times (e.g., 3 min calculation time for 1 s of experimental testing time using a 2 million element mesh).