Heat generation of H2 starved cells in automotive PEMFC stacks

Fuel gross starvation is an irregular operation state, which occurs when fuel cells are operated in multi-cell stacks with insufficient supply of hydrogen. The cell voltage polarity is reversed to negative values in this case, so the fuel cell acts like an electrical resistance. Two characteristic experiments of fuel starvation are compared. Each experiment intentionally provoked the error state of fuel starvation of a single cell in a 20-cell stack. One scenario used a metal containing bipolar plate (BP), and the experiment ended quickly in a rapid decrease of cell voltage to -10 V, causing catastrophic cell failure. The other experiment used carbon composite BPs, whereas no such destructive behavior could be observed.