US 7,740,964 B2 · Adaptive anode nitrogen management control

Abstract

A method is provided for controlling the concentration of nitrogen in a fuel cell stack. The method includes providing a fuel cell stack with cathode passages and anode passages including a valve in communication with the anode passages. The method further comprises selecting a maximum desired amount of nitrogen to be found in the fuel cell stack and calculating an actual amount of nitrogen in the fuel cell stack. Next, the method provides for comparing the maximum desired amount of nitrogen in the fuel cell stack to the actual amount of nitrogen in the fuel cell stack, and opening the valve if the actual amount of nitrogen in the fuel cell stack is greater than the maximum desired amount of nitrogen in the fuel cell stack. The method calculates the actual amount of nitrogen in the fuel cell stack based on an amount of nitrogen that enters the anode passages due to an age of the fuel cell stack.

Claims13

Dependent claims

A method for controlling the concentration of nitrogen in a fuel cell stack, comprising:

providing a fuel cell stack with cathode passages and anode passages including a valve in communication with the anode passages and a permeable membrane having a first face adjacent to the cathode passages and a second face adjacent to the anode passages;
calculating an actual amount of nitrogen in the fuel cell stack;
comparing a predetermined maximum desired amount of nitrogen in the fuel cell stack to the actual amount of nitrogen in the fuel cell stack;
and
opening the valve if the actual amount of nitrogen in the fuel cell stack is greater than the maximum desired amount of nitrogen in the fuel cell stack,
wherein calculating the actual amount of the nitrogen in the fuel cell stack includes:
determining an amount of nitrogen that enters the anode passages due to an age of the fuel cell stack;
determining a permeation coefficient of the permeable membrane;
and
determining a bleed rate correction factor associated with the rate of increase of nitrogen into the anode passages.

7 more elements

A method for controlling the concentration of nitrogen in a fuel cell stack, comprising:

providing a fuel cell stack with cathode passages and anode passages including a valve in communication with said anode passages;
selecting a maximum desired amount of nitrogen to be found in the fuel cell stack;
calculating a bleed rate of the nitrogen between the cathode passages and the anode passages due to the age of the fuel cell stack;
calculating a crossover rate of nitrogen which permeates into the anode passages from an oxidant gas disposed in the cathode passages;
calculating an actual amount of nitrogen in the fuel cell stack based on the bleed rate of the nitrogen and the crossover rate;
comparing the maximum desired amount of nitrogen in the fuel cell stack to the actual amount of nitrogen in the fuel cell stack;
and
opening the valve if the actual amount of nitrogen in the fuel cell stack is greater than the maximum desired amount of nitrogen in the fuel cell stack,
wherein the maximum desired amount of nitrogen in the fuel cell is from about thirty percent to about forty percent.

6 more elements

Dependencies are inferred from the claim text.

Adaptive anode nitrogen management control

Life of this patent

Adaptive anode nitrogen management control

Life of this patent

Abstract

Claims13