Patent ID: 6673481
Filing Date: 2004-01-06
Classification: H01M,Y02E

Abstract:
A method of initiating operation of an electric load powered by a power plant including a proton exchange membrane fuel cell stack at least part of which is at a temperature below the freezing temperature of water, said stack having a plurality of cells and having water passages connected to a water circulation system to provide at least one of (i) product water removal (ii) condensate removal (iii) humidification of reactants, and (iv) cooling, each of said cells including a membrane electrode assembly disposed between an anode support plate and a cathode support plate, a fuel reactant gas flow field on an anode side of said cell, and an oxidant reactant gas flow field on a cathode side of said cell, said method comprising:(a) monitoring the current provided by and voltage across said stack; (b) with said stack disconnected from said load, providing at least stochiometric requirement of fuel reactant gas to said fuel flow fields and at least stochiometric requirement of air from said ambient environment to said oxidant flow fields; (c) upon occurrence of a condition selected from (v) within less than about 20 seconds from step (b) and (vi) when open circuit voltage across said stack is detected, connecting said stack to power said load; and (d) upon the expiration of approximately five minutes following step (c), starting circulation of water flowing within said water passages.