Patent ID: 8137853

Claim:
A membrane humidifier for a fuel cell comprising: a wet side plate having a plurality of flow channels formed therein on both a top side and a bottom side thereof, wherein said wet plate has a folded outer edge, the flow channels of said wet side plate adapted to facilitate a flow of a wet gas therethrough; a dry side plate having a plurality of flow channels formed therein on both a top side and a bottom side thereof, wherein said dry plate has a folded outer edge, the flow channels of said dry side plate adapted to facilitate a flow of a dry gas therethrough, wherein the flow channels of said wet side plate create a cross-flow pattern with the flow channels of said dry side plate; a first diffusion medium disposed between said wet side plate and said dry side plate adjacent said wet side plate, said first diffusion medium adapted to permit a transfer of water vapor therethrough; a second diffusion medium disposed between said wet side plate and said dry side plate adjacent said dry side plate, said second diffusion medium adapted to permit a transfer of water vapor therethrough; and a membrane disposed between said first diffusion medium and said second diffusion medium, said membrane adapted to permit a transfer of water vapor therethrough, wherein said first diffusion medium abuts the membrane and said wet side plate and said second diffusion medium abuts the membrane and said dry side plate, and wherein water vapor in the wet gas is transferred through said first diffusion medium, said membrane, and said second diffusion medium to the dry gas.