Patent ID: 8083821

Claim:
A system for modifying the atmosphere within an enclosed space, said system comprising: (a) a first electrochemical device, said first electrochemical device comprising a solid polymer electrolyte, an anode coupled to a face of said solid polymer electrolyte, and a cathode coupled to an opposing face of said solid polymer electrolyte; (b) means for supplying water to said anode; (c) means for supplying an oxygen-containing fluid to said cathode, said oxygen-containing fluid being selectively drawn from either the enclosed space or the ambient atmosphere; (d) a power supply for applying a controlled voltage or current to the first electrochemical device to cause said anode to evolve oxygen from water to yield an oxygen-enriched fluid and to cause said cathode to consume oxygen from the oxygen-containing fluid to yield an oxygen-depleted fluid; (e) means for monitoring oxygen concentration within the enclosed space; and (f) means, responsive to the monitored oxygen concentration within the enclosed space and an oxygen concentration set point, for selectively conducting either the oxygen-enriched fluid or the oxygen-depleted fluid to the enclosed space for use in reaching the oxygen concentration set point.