Patent ID: 7855024

Claim:
An electrochemical cell system, comprising: at least one electrochemical cell comprising a hydrogen electrode and an oxygen electrode with a proton exchange membrane disposed therebetween and in intimate contact therewith; a compartmentalized storage tank, comprising a housing, a first fluid storage section disposed within the housing, a second fluid storage section disposed within the housing, the first and second fluid storage sections being separated by a movable divider, and a constant force spring disposed between the housing and the movable divider to exert a constant force on the movable divider to cause a pressure P 1 in the first fluid storage section to be greater than a pressure P 2 in the second fluid storage section, thereby defining a substantially constant pressure differential, the storage tank having a first port in fluid communication with the oxygen electrode and a second port in fluid communication with the hydrogen electrode, wherein the constant force spring comprises two self-winding springs having opposing winds; and a flexible conduit line within the second storage section and coupled between the first storage section and the first port.