Wicking layer for managing moisture distribution in a fuel cell

Abstract

An exemplary device for managing moisture content within a fuel cell includes a reactant distribution plate having a plurality of members that establish reactant flow channels that are open on at least one side of the plate. A wicking layer is against the one side of the plate. The wicking layer includes a first portion that is uninterrupted and covers over at least some of the channels. A second portion of the wicking layer extends along ends of at least some of the members such that sections of the channels coextensive with the second portion are open toward the one side.

1 . A device for managing moisture content within a fuel cell, comprising:
 a reactant distribution plate having a plurality of members that establish reactant flow channels that are open on at least one side of the plate; and   a wicking layer against the one side of the plate, the wicking layer including a first portion that is uninterrupted and covers over at least some of the channels and a second portion that extends along ends of at least some of the members such that sections of the channels coextensive with the second portion are open toward the one side.   
     
     
         2 . The device of  claim 1 , wherein the first portion of the wicking layer is generally coextensive with a condensation zone of the reactant distribution plate. 
     
     
         3 . The device of  claim 2 , wherein the second portion of the wicking layer is positioned along an active zone of the reactant distribution plate. 
     
     
         4 . The device of  claim 2 , comprising coolant flow channels having an inlet near the reactant flow channels for establishing the condensation zone. 
     
     
         5 . The device of  claim 1 , wherein the second portion of the wicking layer is positioned along an active zone of the reactant distribution plate. 
     
     
         6 . The device of  claim 1 , wherein the wicking layer comprises a third portion that is uninterrupted and covers over at least some of the channels of the reactant distribution plate, the first and third portions being near opposite ends of the second portion. 
     
     
         7 . The device of  claim 6 , wherein the first portion is positioned near a condensation zone of the reactant distribution plate, the second portion is positioned near an active zone of the reactant distribution plate and the third portion is positioned near a gas inlet side of the channels of the reactant distribution plate. 
     
     
         8 . The device of  claim 1 , comprising a gas diffusion layer and wherein the wicking layer is between the gas diffusion layer and the reactant distribution plate. 
     
     
         9 . The device of  claim 1 , wherein the wicking layer comprises a hydrophilic carbon. 
     
     
         10 . The device of  claim 1 , wherein the wicking layer comprises a tin oxide treated paper that comprises carbon fibers. 
     
     
         11 . A method of managing moisture distribution within a fuel cell assembly, comprising:
 positioning a wicking layer between a reactant distribution plate and a gas diffusion layer;   covering over a portion of at least some gas flow channels in the reactant distribution plate with a first portion of the wicking layer; and   leaving other portions of the gas flow channels exposed and open along a second portion of the wicking layer.   
     
     
         12 . The method of  claim 11 , comprising
 covering over another portion of at least some of the gas flow channels with a third portion of the wicking layer.   
     
     
         13 . The method of  claim 12 , wherein the second portion of the wicking layer is between the first portion and the third portion. 
     
     
         14 . The method of  claim 11 , comprising
 positioning the first portion near a condensation zone of the reactant distribution plate.   
     
     
         15 . The method of  claim 14 , comprising
 introducing a coolant near a portion of the gas flow channels receive a gas to establish the condensation zone.   
     
     
         16 . The method of  claim 11 , comprising
 positioning the second portion along an active zone of the reactant distribution plate.