Fuel Cell Components, Stacks and Modular Fuel Cell Systems

Abstract

A fuel cell power module includes a cylindrical housing encasing a fuel cell stack and an air supply. The housing has a major interior surface. The fuel cell stack can be cylindrical or hexagonal, and comprises fuel cells having an anode and an anode flow field plate, a cathode and a cathode flow field plate, and a membrane electrolyte interposed between the anode and the cathode. The air supply is directed to the plurality of fuel cell cathode flow field plates via a plenum defined by a space between the fuel cell stack and the housing major interior surface. The hexagonal fuel cell stack can be formed by a plurality of fuel cell groups shaped such that when aligned the fuel cell groups together constitute the hexagonal fuel cell stack.

What is claimed is: 
     
         1 . A fuel cell power module comprising:
 (a) a cylindrical housing having a major interior surface;   (h) a cylindrical fuel cell stack contained within said housing, said fuel cell stack comprising a plurality of fuel cells interposed between a pair of compression end-plates, each of said fuel cells comprising an anode and an anode flow field plate, a cathode and a cathode flow field plate, and a membrane electrolyte interposed between said anode and said cathode; and   (c) an air supply directed to said plurality of fuel cell cathode flow field plates via an annular plenum defined by a space between said cylindrical fuel cell stack and said cylindrical housing major interior surface.   
     
     
         2 . The fuel cell power module of  claim 1 , wherein said air supply comprises an axially-mounted fan-motor assembly contained within said housing. 
     
     
         3 . The fuel cell power module of  claim 1 , wherein said plenum serves as an oxidant supply manifold and wherein said air supply directs said air into said plenum such that at least a portion of said air (i) enters said plurality of cathode flow field plates, (ii) flows substantially radially through said plurality of cathode flow field plates, and (iii) exits said fuel cell stack via a central oxidant exhaust manifold. 
     
     
         4 . The fuel cell power module of  claim 1 , further comprising:
 (d) a fuel inlet manifold comprising aligned first openings formed in each of said plurality of fuel cells for directing a fuel supply stream to each of said plurality of anode flow field plates; and   (e) a fuel outlet manifold comprising aligned second openings formed in each of said plurality of fuel cells for discharging a fuel exhaust stream from each of said plurality of anode flow field plates.   
     
     
         5 . The fuel cell power module of  claim 1 , further comprising:
 (d) a plurality of coolant pathways, each of said pathways disposed between adjacent pairs of said plurality of fuel cells, wherein said air supply is capable of supplying air to said plurality of coolant pathways via said annular plenum.   
     
     
         6 . The fuel cell power module of  claim 5 , further comprising:
 (e) an adjustment mechanism for adjusting air flow to said plurality of cathode flow field plates and for adjusting air flow to said plurality of coolant pathways.   
     
     
         7 . The fuel cell power module of  claim 1 , further comprising:
 (d) a plurality of coolant pathways, each of said pathways disposed between adjacent pairs of said plurality of fuel cells, wherein said coolant pathways are fluidly connected to a liquid coolant circulation system.   
     
     
         8 . The fuel cell power module of  claim 1 , further comprising:
 (d) a humidifier for humidifying a reactant stream supplied to said plurality of fuel cells, wherein said humidifier is contained within said cylindrical housing.   
     
     
         9 . The fuel cell power module of  claim 1 , wherein said cylindrical housing comprises a compression mechanism for compressing the fuel cell stack, and wherein said compression mechanism comprises a threaded end plate capable of engaging a corresponding threaded portion of said major interior of said cylindrical housing, whereby applying rotational force to said end plate urges said end plate toward said cylindrical fuel cell stack. 
     
     
         10 . The fuel cell power module of  claim 1 , wherein said cylindrical housing comprises a compression mechanism for compressing the fuel cell stack, and wherein said compression mechanism comprises a notched end plate capable of engaging a corresponding notched receptacle formed in said major interior of said cylindrical housing, whereby said end plate is urged toward said fuel cell stack when said notched end plate engages said notched receptacle. 
     
     
         11 . A fuel cell power module comprising:
 (a) a cylindrical housing having a major interior surface;   (b) a hexagonal fuel cell stack contained within said housing, said fuel cell stack comprising a plurality of fuel cells interposed between a pair of compression end-plates, each of said fuel cells comprising an anode and an anode flow field plate, a cathode and a cathode flow field plate, and a membrane electrolyte interposed between said anode and said cathode; and   (c) an air supply directed to said plurality of fuel cell cathode flow field plates via a plenum defined by a space between said hexagonal fuel cell stack and said cylindrical housing major interior surface.   
     
     
         12 . The fuel cell power module of  claim 11 , wherein said air supply comprises an axially-mounted fan-motor assembly contained within said housing. 
     
     
         13 . The fuel cell power module of  claim 11 , wherein said plenum serves as an oxidant supply manifold and wherein said air supply directs said air into said plenum such that at least a portion of said air (i) enters said plurality of cathode flow field plates, (ii) flows substantially radially through said plurality of cathode flow field plates, and (iii) exits said fuel cell stack via a central oxidant exhaust manifold. 
     
     
         14 . The fuel cell power module of  claim 11 , further comprising:
 (d) a fuel inlet manifold comprising aligned first openings formed in each of said plurality of fuel cells for directing a fuel supply stream to each of said plurality of anode flow field plates; and   (e) a fuel outlet manifold comprising aligned second openings formed in each of said plurality of fuel cells for discharging a fuel exhaust stream from each of said plurality of anode flow field plates.   
     
     
         15 . The fuel cell power module of  claim 11 , further comprising:
 (d) a plurality of coolant pathways, each of said pathways disposed between adjacent pairs of said plurality of fuel cells, wherein said air supply is capable of supplying air to said plurality of coolant pathways via said plenum.   
     
     
         16 . The fuel cell power module of  claim 15 , further comprising:
 (e) an adjustment mechanism for adjusting air flow to said plurality of cathode flow field plates and for adjusting air flow to said plurality of coolant pathways.   
     
     
         17 . The fuel cell power module of  claim 11 , further comprising:
 (d) a plurality of coolant pathways, each of said pathways disposed between adjacent pairs of said plurality of fuel cells, wherein said coolant pathways are fluidly connected to a liquid coolant circulation system.   
     
     
         18 . The fuel cell power module of  claim 11 , further comprising:
 (d) a humidifier for humidifying a reactant stream supplied to said plurality of fuel cells, wherein said humidifier is contained within said cylindrical housing.   
     
     
         19 . The fuel cell power module of  claim 11 , wherein said cylindrical housing comprises a compression mechanism for compressing said fuel cell stack, and wherein said compression mechanism comprises a threaded end plate capable of engaging a corresponding threaded portion of said major interior surface of said cylindrical housing, whereby applying rotational force to said end plate urges said end plate toward said fuel cell stack. 
     
     
         20 . The fuel cell power module of  claim 11 , wherein said cylindrical housing comprises a compression mechanism for compressing said fuel cell stack, and wherein said compression mechanism comprises a notched end plate capable of engaging a corresponding notched receptacle formed in said major interior surface of said cylindrical housing, whereby said end plate is urged toward said fuel cell stack when said notched end plate engages said notched receptacle.