Patent ID: 7887960
Filing Date: 2011-02-15
Classification: H01M,Y02E

Abstract:
1. A method of operating an electrochemical conversion assembly comprising a plurality of electrochemical conversion cells arranged in a conductively coupled fuel cell stack, wherein respective ones of said cells comprise membrane electrode assemblies positioned between first and second reactant flowfields and said membrane electrode assemblies comprise a proton exchange membrane, said method comprising: initiating operation of said fuel cell stack according to an initial set of operating parameters comprising hydration, wherein said operation of said fuel cell stack runs through a plurality of operational cycles characterized by changes in humidification, of said membrane electrode assemblies; extracting cyclic stress data representative of said plurality of operational cycles; determining a life spent value L determining an actual usage value L comparing said life spent value L controlling at least one operating parameter comprising hydration of said electrochemical conversion assembly as a function of said comparison of said life spent value L