Controlling PEMFC stack flooding

An earth moving machine including a system for detecting a humidity level at a cathode of a fuel cell stack including one or more proton exchange membrane fuel cells and determining a flooding probability of the fuel cell stack based on the humidity level, the system comprising:

• a fuel cell stack including a plurality of proton exchange membrane fuel cells, each proton exchange membrane fuel cell including an exhaust;
• a voltage detector;
• a humidity detector;
• and
• a controller configured to:
• receive a voltage as measured at an anode of one or more of the proton exchange membrane fuel cells with the voltage detector;
• determine a humidity level at the exhaust of the one or more of the proton exchange membrane fuel cells;
• and
• implement one or more actions based on the voltage and the humidity level, the actions including:
• reduce a load on the proton exchange membrane fuel cell;
• increase an air flow at a cathode of the one or more proton exchange membrane fuel cells;
• decrease an inlet humidity at an inlet to the one or more proton exchange membrane fuel cells;
• or
• increase a temperature of the one or more proton exchange membrane fuel cells.

A method of reducing a relative humidity within a cathode of a fuel cell stack comprising one or more proton exchange membrane fuel cells, the method comprising:

• determining a voltage at an anode of one or more of the proton exchange membrane fuel cells with a voltage detector;
• determining a humidity level at an exhaust of one or more of the one or more of the proton exchange membrane fuel cells;
• and
• implementing one or more actions to reduce the relative humidity based on the voltage and the humidity level, the actions including:
• reducing a load on the proton exchange membrane fuel cell;
• increasing an air flow at a cathode of the one or more proton exchange membrane fuel cells;
• decreasing an inlet humidity at an inlet to the one or more proton exchange membrane fuel cells;
• or
• increasing a temperature of the one or more proton exchange membrane fuel cells.