Environmental compensation method and apparatus for a fuel cell assembly

An environmental compensation apparatus for a fuel cell stack having a plurality of electrochemical fuel cell assemblies, said fuel cell assemblies each having an electrolyte, an anode, a cathode, an anode and a cathode flow field plates and a coolant channel through which a flow of coolant is circulated, said apparatus comprising:

• an inlet coolant manifold for introducing said coolant to said fuel cell stack;
• an exhaust coolant manifold for exhausting said coolant from said fuel cell stack;
• a compressible material dispersed throughout said coolant;
• and
• wherein said compressible material compensates for the expansion of said coolant within said coolant channel during times when said fuel cell stack experiences temperatures approximately below a predetermined temperature.

An environmental compensation apparatus for a fuel cell system having in combination a coolant system and an electrochemical fuel cell assembly, said fuel cell assembly having an electrolyte, an anode, a cathode, an anode and a cathode flow field plates and a coolant channel through which a flow of coolant is circulated, said apparatus comprising:

• an inlet coolant manifold for introducing said coolant to said fuel cell assembly;
• an exhaust coolant manifold for exhausting said coolant from said fuel cell assembly;
• a compressible material dispersed throughout said coolant;
• and
• wherein said compressible material compensates for the expansion of said coolant within said coolant system during times when said fuel cell system experiences temperatures approximately below a predetermined temperature.

A method of providing environmental compensation for a fuel cell assembly, said fuel cell assembly having an electrolyte, an anode, a cathode, anode and cathode flow field plates and a coolant channel through which a flow of coolant is circulated, said method comprising the steps of:

• dispersing a compressible material throughout said coolant;
• introducing said coolant to said fuel cell assembly through an inlet coolant manifold;
• circulating said coolant through said coolant channel;
• and
• exhausting said coolant from said fuel cell assembly through an exhaust coolant manifold.

A method of providing environmental compensation for a fuel cell system having in combination a coolant system and an electrochemical fuel cell assembly, said fuel cell assembly having an electrolyte, an anode, a cathode, anode and cathode flow field plates and a coolant channel through which a flow of coolant is circulated, said method comprising the steps of:

• dispersing a compressible material throughout said coolant at approximately 5% to approximately 30% of a total volume of said coolant within said fuel cell system;
• introducing said coolant to said fuel cell assembly through an inlet coolant manifold;
• circulating said coolant through said coolant channel;
• exhausting said coolant from said fuel cell assembly through an exhaust coolant manifold;
• adapting one of said anode and said cathode flow field plates to include pores of a first predetermined diameter;
• adapting said coolant channels to have a second predetermined diameter;
• and
• forming said compressible material as a plurality of polymeric microspheres, each of said microspheres being adapted to have a diameter larger than said first predetermined diameter and smaller than said second predetermined diameter.