초록 ▼

Method and apparatus for cooling and recirculating oxidant to the cathode of a fuel cell stack. Heat energy is removed from the fuel cell stack through utilization of excess air or other oxidant relative to the stoichiometric amount for reaction with a hydrogen-containing fuel. Reaction products, in

Method and apparatus for cooling and recirculating oxidant to the cathode of a fuel cell stack. Heat energy is removed from the fuel cell stack through utilization of excess air or other oxidant relative to the stoichiometric amount for reaction with a hydrogen-containing fuel. Reaction products, including excess air and water, flow to a nozzle upstream of a flow constricting venturi. A coolant, such as liquid water in a fine spray form, is injected through the venturi and draws the reaction products through the venturi. The mixing of the coolant and the reaction products results in a condensation of the high temperature reaction product water vapor and further dehumidification of the reaction products takes place in a passive separator such as a demister. Coolant is injected into the venturi in sufficient quantity to develop the pressure head necessary to recirculate the cooled and dehumidified air through a conduit system and back to the fuel cell stack. A supply of makeup air is also provided. Coolant and water collected in the passive separator can also be recirculated for injection through the venturi.

대표청구항 ▼

A fuel cell system comprising: a fuel cell stack including an anode and a cathode; means for supplying a hydrogen-containing fuel to said anode; means for supplying an oxygen-containing oxidant to said cathode in an amount in excess of the stoichiometric amount relative to said fuel; means for condu

A fuel cell system comprising: a fuel cell stack including an anode and a cathode; means for supplying a hydrogen-containing fuel to said anode; means for supplying an oxygen-containing oxidant to said cathode in an amount in excess of the stoichiometric amount relative to said fuel; means for conducting reaction products including excess oxidant and water vapor from said cathode; means for cooling and flowing said products through a flow constriction, said cooling and flow means including a liquid coolant injector; means disposed downstream of said flow constriction for separating said coolant, oxidant and water into a vaporous portion having a large oxidant and small coolant and water content and a liquid portion having a large coolant and water content and a small oxidant content, said separating means including an outlet for said vapor portion; and a conduit interconnecting said outlet and said cathode; said cooling and flow means providing sufficient pressure head to flow said vaporous portion through said interconnecting conduit to said cathode.