US 6,982,129 B1
Method and apparatus for monitoring equivalent series resistance and for shunting a fuel cell
Lijun Bai, Spokane, Wash. (US); David R. Lott, Spokane, Wash. (US); and Vanell L. Martin, Spokane, Wash. (US)
Assigned to Relion, Inc., Spokane, Wash. (US)
Filed on May 06, 2003, as Appl. No. 10/431,158.
Application 10/431158 is a division of application No. 10/056543, filed on Jan. 23, 2002, granted, now 6,620,538.
Int. Cl. H01M 8/04 (2006.01); H01M 8/02 (2006.01)
U.S. Cl. 429—23 3 Claims
OG exemplary drawing
 
1. A fuel cell power system comprising:
a plurality of fuel cells which are configured such that at least one of the fuel cells may be selectively decoupled from a load while the remaining fuel cells continue to supply electrical power to the load;
circuitry configured to determine equivalent series resistance of at least one of the plurality of fuel cells in timed relation to the decoupling of the at least one of the fuel cells from the load, and wherein the circuitry is further configured to determine a hydration level of the at least one of the plurality of fuel cells based upon the determined equivalent series resistance; and
circuitry configured to selectively short circuit at least one of the plurality of fuel cells in timed relation to the selective decoupling of the at least one of the fuel cells from the load.