Patent ID: 8268508

Claim:
A fluid tank used as a water controller system for fuel cells, wherein the fluid tank comprises a housing defining an inner space for receiving a liquid-phase component and a gas-phase component, discharging carbon dioxide and air of the gas-phase component, and supplying the liquid-phase component into a fuel cell stack, and wherein the housing is constructed in a dual structure in which a hermetically-sealed type inner case is disposed inside a hermetically-sealed type outer case such that a space defined between the hermetically-sealed type cases is filled with water, the housing is provided on the outer case at one side surface thereof, the one side surface being perpendicular to another side surface thereof at which a cathode-side introduction pipe and an anode-side introduction pipe are disposed, with one or more gas and liquid separation membranes, and the housing is provided on the inner case at one side surface thereof, the one side surface being perpendicular to another side surface thereof at which a cathode-side introduction pipe and an anode-side introduction pipe are disposed, with one or more gas and liquid separation membranes, and the housing is provided on the outer case at an opposite side surface thereof, the opposite side surface being perpendicular to another opposite side surface thereof at which a cathode-side introduction pipe and an anode-side introduction pipe are disposed, with one or more gas and liquid separation membranes, and the housing is provided on the inner case at an opposite surface thereof, the opposite side surface being perpendicular to another opposite side surface thereof at which a cathode-side introduction pipe and an anode-side introduction pipe are disposed, with one or more gas and liquid separation membranes, whereby the gas-phase component passes through the water filled in the space defined between the inner and outer cases when the gas-phase component is discharged to the outside from the inner space of the housing.