System for protecting a fuel cell from cold temperatures

A protection system for a fuel cell comprising:

• a fuel cell stack;
• a cooling system for the fuel cell that controls a temperature of the fuel cell;
• and
• a controller operable in a first mode of operation when a time T for a next start-up is not known and a second mode of operation when the time T for the next start-up is known, wherein in the first mode and a time TF is the time an estimated future ambient temperature is estimated to fall to near freezing, at TF the cooling system purges the fuel cell, and in the second mode at TF the cooling system turns on without starting the fuel cell, wherein the controller is programmed to estimate a time Y1 required for a fuel cell stack temperature to fall to TF, and estimate a time Y2 required for the fuel cell stack temperature to drop from fully warmed to TF, and wherein T must be less than a sum of Y1+Y2, before the cooling system is turned on without starting the fuel cell.

A protection system for a fuel cell comprising:

• a fuel cell stack;
• a cooling system for the fuel cell that controls a temperature of the fuel cell stack when operating and warms the fuel cell stack for start-up, and
• a controller programmed to—
• shutdown the fuel cell stack when requested,
• store a predicted start-up time T,
• store an ambient temperature value;
• estimate a time Y1 required for the fuel cell stack temperature to fall to a selected near freezing fuel cell temperature,
• estimate a time Y2 required for the fuel cell stack to drop from fully warmed to the selected near freezing fuel cell temperature, and
• start the cooling system when T is known and Y1<T and T<Y1+Y2.