Sensor cell for an electrochemical fuel cell stack
First Claim
1. In an electrochemical fuel cell stack comprising a plurality of fuel cells, each of said fuel cells comprising an anode comprising an anode electrocatalyst, a cathode comprising a cathode electrocatalyst, and an ion exchange membrane interposed between said anode and said cathode, the improvement comprising:
- at least one of said plurality of fuel cells being a sensor cell having at least one structural dissimilarity with respect to the remaining fuel cells of said plurality, wherein during operation of said stack, said structural dissimilarity induces at least one of an electrical and thermal process in said sensor cell which is not simultaneously induced in said remaining fuel cells under substantially the same operating conditions; and
wherein during operation of said stack, said sensor cell and at least one of said remaining cells are connected to a comparator for comparing said electrical or thermal response of said sensor cell with that of said at least one of said remaining cells.
1 Assignment
0 Petitions
Accused Products
Abstract
An electrochemical fuel cell stack includes a plurality of fuel cells. At least one of the fuel cells is a sensor cell. The sensor cell has at least one structural dissimilarity with respect to the remaining fuel cells of the plurality. The structural dissimilarity may include, for example, a reduced sensor cell electrochemically active area, reduced electrocatalyst loading, modified anode or cathode flow field, different electrocatalyst composition, or a modified coolant flow field configuration. The sensor cell operates under substantially the same conditions as the remaining cells in the stack. However, in response to a change in a particular stack operating condition, an electrical or thermal response, preferably a voltage change, is induced in the sensor cell which is not simultaneously induced in the remaining fuel cells. Thus, the sensor cell can detect undesirable conditions and its response can be used to initiate corrective action. More than one sensor cell, specific to different types of conditions, may be employed in the stack. In the absence of undesirable conditions, the sensor cell can function as a power-producing fuel cell.
41 Citations
39 Claims
-
1. In an electrochemical fuel cell stack comprising a plurality of fuel cells, each of said fuel cells comprising an anode comprising an anode electrocatalyst, a cathode comprising a cathode electrocatalyst, and an ion exchange membrane interposed between said anode and said cathode, the improvement comprising:
-
at least one of said plurality of fuel cells being a sensor cell having at least one structural dissimilarity with respect to the remaining fuel cells of said plurality, wherein during operation of said stack, said structural dissimilarity induces at least one of an electrical and thermal process in said sensor cell which is not simultaneously induced in said remaining fuel cells under substantially the same operating conditions; and
wherein during operation of said stack, said sensor cell and at least one of said remaining cells are connected to a comparator for comparing said electrical or thermal response of said sensor cell with that of said at least one of said remaining cells. - View Dependent Claims (2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30)
-
-
31. A method of operating an electrochemical fuel cell stack comprising a fuel cell stack comprising a plurality of solid polymer fuel cells, at least one of said plurality of fuel cells being a sensor cell having at least one structural dissimilarity with respect to the remaining fuel cells of said plurality wherein, during operation of said stack, said structural dissimilarity induces at least one of an electrical and thermal response in said sensor cell which is not simultaneously induced in said remaining fuel cells under substantially the same operating conditions, said method comprising:
-
monitoring at least one of an electrical and thermal operating parameter of said sensor cell and the same parameter of at least one of said remaining cells;
comparing said monitored operating parameter of said sensor cell with that of said at least one remaining cell;
generating an output signal if said compared parameters differ by more than a predetermined threshold amount indicative of an undesirable operating condition. - View Dependent Claims (32, 33, 34, 35, 36, 37, 38, 39)
-
Specification