Fuel cell

#The invention relates to fuel cells.

#A fuel cell can convert chemical energy to electrical energy by promoting a chemical reaction between two gases.

#One type of fuel cell includes a cathode flow field plate, an anode flow field plate, a membrane electrode assembly disposed between the cathode flow field plate and the anode flow field plate, and two gas diffusion layers disposed between the cathode flow field plate and the anode flow field plate. A fuel cell can also include one or more coolant flow field plates disposed adjacent the exterior of the anode flow field plate and/or the exterior of the cathode flow field plate.

#FIG. 1 is a partial schematic diagram of an embodiment of a fuel cell system.

#FIG. 2 is a partial schematic diagram of an embodiment of a fuel cell.

#FIG. 3 shows an embodiment of a cathode flow field plate.

#FIG. 1 shows a fuel cell system 20 including a fuel cell stack 22 that has a plurality of fuel cells 24. Fuel cell system 20 also includes an anode gas supply 26, an anode gas inlet line 28, an anode gas outlet line 30, a cathode gas inlet line 32, a cathode gas outlet line 34, a coolant inlet line 36, and a coolant outlet line 38.

#FIG. 2 shows an embodiment of fuel cell 24 having a membrane electrode assembly (MEA) 40, a non-electrolytic layer 42, gas diffusion layers (GDLs) 44 and 46, a cathode flow field plate 48, and an anode flow field plate 50. MEA 40 includes a cathode 52, an anode 54, and a solid electrolyte 56 between electrodes 52 and 54. Cathode flow field plate 48 has cathode gas channels 250, and anode flow field plate 50 has anode gas channels 280. Fuel cells 24 can be arranged by having the back surface of a cathode flow field plate of one fuel cell serve as the anode flow field plate in an adjacent fuel cell. A plurality of coolant flow field plates (described below) can also be used in this arrangement.

#Non-electrolytic layer 42 is generally configured to reduce, e.g., minimize, the adverse effect of peroxide that can form during operation of fuel cell system 20 and/or to reduce the adverse effect of water that can condense in fuel cells 24. For example, non-electrolytic layer 42 can electrolytically isolate carbon material in GDL 44, e.g., from oxygen, to reduce peroxide generation. In some embodiments, non-electrolytic layer 42 includes a mixture of a catalyst and a non-electrolytic material as a binder.