Direct ammonia alkaline membrane fuel cell and method of operating same
Disclosed is a method of operating an Alkaline Membrane Fuel Cell (AMFC) with direct ammonia feeding. The method may include providing AMFC comprising an anode inlet for receiving ammonia and a cathode inlet for receiving oxygen containing gas; operating the AMFC at an operation temperature of above 80° C.; providing the oxygen containing gas; to a cathode of the AMFC at a pressure above the equilibrium vapor pressure of water at the operation temperature; maintaining the pressure during the operation of the AMFC as to maintain water in substantially liquid phase near the cathode; and providing the ammonia to an anode of the AMFC.
1. A method of operating an Alkaline Membrane Fuel Cell (AMFC) with direct ammonia feeding, the method comprising:
providing AMFC comprising: a solid electrolyte membrane free of aqueous electrolyte, an anode inlet for receiving ammonia and a cathode inlet for receiving oxygen containing gas;
operating the AMFC at an operation temperature of above 95° C.;
providing the oxygen containing gas to a cathode of the AMFC at a pressure above the equilibrium vapor pressure of water at the operation temperature;
and
providing the ammonia to an anode of the AMFC by providing one of:
ammonia in a gas phase at a pressure above the equilibrium vapor pressure of water at the operation temperature;
ammonia as an aqueous ammonia solution; and
ammonia in a gas phase while adding humidity to the oxygen containing gas.
2. The method of claim 1 , wherein the operation temperature is above 100° C.
3. An Alkaline Membrane Fuel Cell (AMFC) with direct ammonia feed, comprising:
a solid electrolyte anion conducting membrane free of aqueous electrolyte;
an anode electrode comprising an anode catalyst layer;
a cathode electrode comprising a cathode catalyst layer;
an ammonia source in fluid connection with the anode electrode:
an oxygen containing gas source in fluid connection to the cathode electrode,
wherein the oxygen containing gas is provided at a pressure above the equilibrium vapor pressure of water at the operation temperature; and
a cooling element controlled to maintained the temperature in the AMFC above 95° C.
4. The Alkaline Membrane Fuel Cell of claim 3 , wherein the oxygen containing gas is provided from a pressurized source.
5. Alkaline Membrane Fuel Cell of claim 3 , wherein the oxygen containing gas source further comprises a humidifier for providing humidity to the oxygen containing gas.
6. Alkaline Membrane Fuel Cell of claim 3 , wherein the ammonia source is a pressurized ammonia source and the ammonia is provided in a gas phase at a pressure above the equilibrium vapor pressure of water at the operation temperature.
7. The Alkaline Membrane Fuel Cell of claim 6 , wherein the ammonia source comprises a humidifier for providing humidity to the ammonia.
8. Alkaline Membrane Fuel Cell of claim 3 , wherein the ammonia source comprises an aqueous solution of ammonia.
9. Alkaline Membrane Fuel Cell of claim 3 , wherein the operation temperature is above 100° C.