Pem fuel cell stack inlet water regulation system

Abstract

A fuel cell stack assembly is disclosed that includes a porous member disposed within a flow path for a reactant. A fluid collection member is provided within the flow path adjacent to and in fluid communication with the porous member. The porous member and the fluid collection member cooperate to collect liquid water from the reactant flowing in the flow path, wherein the collected liquid water may be drained from the fluid collection member.

What is claimed is: 
     
         1 . A fluid regulation system for a fuel cell stack comprising:
 a porous element disposed in an inlet formed in a first end plate of the fuel cell stack, a peripheral edge of the porous element abutting a surface forming the inlet, wherein the porous element spans the inlet, the porous element effective to collect a liquid water from a reactant gas flowing therethrough; and   a fluid collection member disposed in an inlet conduit in fluid communication with the inlet, the fluid collection member in fluid communication with the porous element.   
     
     
         2 . The system according to  claim 1 , wherein the porous element is formed from a hydrophilic material. 
     
     
         3 . The system according to  claim 1 , further comprising a fluid conduit in fluid communication with the fluid collection member to provide a flow path to drain the liquid water from the fluid collection member. 
     
     
         4 . The system according to  claim 3 , including a flow restrictor disposed in the fluid conduit to control a flow of the reactant gas therethrough. 
     
     
         5 . The system according to  claim 4 , wherein the flow restrictor is one of a nozzle, a wicking material, and a hydrophilic porous element. 
     
     
         6 . The system according to  claim 3 , wherein the porous element is formed from one of a hydrophilic material and a hydrophobic material. 
     
     
         7 . The system according to  claim 1 , wherein the porous element collects a liquid water entrained in the reactant gas flowing through the porous element. 
     
     
         8 . The system according to  claim 7 , wherein the liquid water collected is received in the fluid collection member. 
     
     
         9 . The system according to  claim 7 , wherein the liquid water collected is evaporated into the reactant gas flowing therethrough. 
     
     
         10 . The system according to  claim 1 , wherein the porous element has a convex first surface for collecting the liquid water. 
     
     
         11 . A fuel cell stack assembly comprising:
 a first end plate;   at least one fuel cell;   a fluid inlet providing a flow path for a reactant gas to the at least one fuel cell;   a porous element disposed in the first end plate, wherein the reactant gas is caused to flow through the porous element and into the at least one fuel cell, the porous element effective to collect a liquid water from the reactant gas flowing therethrough; and   a fluid collection member disposed in the fluid inlet in fluid communication with the porous element, the fluid collection member adapted to receive the liquid water from the porous element.   
     
     
         12 . The fuel cell stack assembly according to  claim 11 , the fluid inlet further comprising:
 an inlet header in communication with the at least one fuel cell;   an inlet formed in the first end plate, the inlet in fluid communication with the inlet header; and   an inlet conduit in fluid communication with the inlet formed in the first end plate, wherein the fluid collection member is disposed beneath the inlet formed in the first end plate.   
     
     
         13 . The fuel cell stack assembly according to  claim 12 , wherein the porous element is a substantially cone shaped member having a peripheral edge, the peripheral edge abutting a surface forming the inlet, wherein the porous element spans the inlet. 
     
     
         14 . The fuel cell stack assembly according to  claim 11 , wherein the porous element is adapted to selectively collect the liquid water entrained in the reactant gas flowing therethrough and evaporate the liquid water into the reactant gas flowing therethrough. 
     
     
         15 . The fuel cell stack assembly according to  claim 11 , further comprising a fluid conduit in fluid communication with the fluid collection member to provide a flow path to drain fluid from the fluid collection member. 
     
     
         16 . The fuel cell stack assembly according to  claim 15 , including a flow restrictor disposed in the fluid conduit to control a flow of the reactant gas therethrough. 
     
     
         17 . The fuel cell stack assembly according to  claim 15 , wherein the porous element is formed from one of a hydrophilic material and a hydrophobic material. 
     
     
         18 . A method of regulating liquid water flowing into a fuel cell comprising the steps of:
 providing a first end plate;   providing at least one fuel cell;   providing a fluid inlet in fluid communication with the at least one fuel cell to provide a flow of a reactant gas to the at least one fuel cell, the fluid inlet including an inlet formed in the first end plate;   providing a porous element in the inlet formed in the first end plate, wherein the porous element spans the inlet formed in first end plate, the porous element effective to collect a liquid water from the reactant gas flowing therethrough; and   providing a fluid collection member in the fluid inlet beneath the porous element, the fluid collection member adapted to receive the liquid water from the porous element.   
     
     
         19 . The method of  claim 18 , further comprising the step of draining the liquid water from the fluid collection member. 
     
     
         20 . The method of  claim 18 , wherein a peripheral edge of the porous element contacts a surface of the inlet formed in the first end plate.