Freeze tolerant fuel cell power plant with a two-component mixed coolant

摘要

A freeze tolerant fuel cell power plant ( 10 ) includes at least one fuel cell ( 12 ), a coolant loop ( 42 ) having a porous water transport plate ( 44 ) secured in a heat and mass exchange relationship with the fuel cell ( 12 ) and a coolant pump ( 46 ) for circulating a coolant through the plate ( 44 ) and for transferring water into or out of the plate ( 44 ) with the coolant. A coolant heat exchanger ( 52 ) removes heat from the coolant, and an accumulator ( 66 ) stores the coolant and fuel cell product water and directs the product water out of the accumulator ( 66 ). The coolant is a two-component mixed coolant liquid circulating through the coolant loop ( 42 ) consisting of between 80 and 95 volume percent of a low freezing temperature water immiscible fluid component and between 5 and 20 volume percent of a water component.