Degasified PEM fuel cell system
AssigneeUTC Fuel Cells, LLC
InventorAlbert P. Grasso
Life of this patent
Estimating the term…
Abstract
A system and method are provided for managing water coolant in a PEM fuel cell system's (10) coolant circuit (14). Gas-liquid separating apparatus (26) serves to efficiently transport liquid coolant containing gases, and to separate gases from the liquid coolant. The liquid coolant having the gases removed therefrom is then circulated through the liquid circuit by means of a conventional pump (24). A vacuum pump (28), such as a liquid eductor (28′), associated with the gas-liquid separating apparatus (26), serves to efficiently transport gas-phase and/or gas-liquid phase, fluids and to assist in the degasification of the liquid coolant. The eductor discharges to a separator/accumulator (30; 30′) which further facilitates separation of gases from liquid coolant.
Claims12
A coolant management system for a polymer electrolyte membrane (PEM) fuel cell power system (10), comprising:
- a) a PEM fuel cell stack assembly (CSA) (12) having an anode region (18) for receiving a supply of fuel reactant, a cathode region (20) for receiving a supply of oxidant reactant, and a cooler (22) having an inlet (27) for receiving a supply of liquid coolant and an outlet (29) for discharging the coolant;
- and
- b) a coolant circuit (14) connected to the cooler inlet (27) and outlet (29) to conduct liquid coolant to, through, and from the CSA cooler (22), the liquid coolant acquiring gas entrained and/or dissolved therein during passage through the CSA cooler (22) and thus forming a gas-liquid coolant mix, the coolant circuit (14) including:
- i) a liquid pump (24;24′) having an inlet (23;23′) and an outlet (25;25′), for creating a pressure rise thereacross and pumping substantially only liquid coolant therethrough;
- and
- ii) separating means (26;26′;26″) connected with the coolant circuit (14) intermediate the CSA coolant region outlet (29) and the pump inlet (23;23′) for separating (30;30′;130;28;28′) gas from the gas-liquid coolant mix, accumulating (30;30′;130) the liquid coolant following the gas separation, and supplying substantially only the liquid coolant to the pump inlet (23;23′), said separating means (26;26′;26″) including a vacuum device (28;28′) connected to the coolant circuit (14) in a region of gas-liquid coolant mix to facilitate transport of at least the gas for separation of the gas from the gas-liquid coolant mix.
A method of coolant management for a polymer electrolyte membrane (PEM) fuel cell power system (10) having a PEM fuel cell stack assembly (CSA) (12) including a cooler (22) having an inlet (27) for receiving a supply of liquid coolant and an outlet (29) for discharging the coolant, and a coolant circuit (14) connected to the cooler inlet (27) and the cooler outlet (29), comprising the steps of:
- a) pumping (24) liquid coolant at a location in the coolant circuit (14) prior to the cooler inlet (27), the liquid coolant being pumped through the CSA cooler (22) wherein the liquid coolant acquires gas entrained and/or dissolved therein, forming a gas-liquid coolant mix exiting the cooler outlet (29);
- b) separating (26;26′) gas from the gas-liquid coolant mix at a location in the coolant circuit (14) intermediate the cooler outlet (29) and the location of the liquid coolant pumping (24) of step a), thereby degasifying the liquid coolant;
- c) accumulating the degasified liquid coolant resulting from the separating step b);
- and
- d) supplying the degasified liquid coolant as at least part of the liquid coolant for the pumping step a).
Dependencies are inferred from the claim text.