A room-temperature carbonate fuel cell has been constructed by modifying anion exchange membranes to transport carbonate. The cells were operated with hydrogen, 1 M methanol, and pure methanol fuels, and dry O-2 and CO2 as the cathode gases. CO2 was produced at the anode, and O-2 and CO2 were necessary at the cathode for operation, indicating that carbonate was the conducting ion. Using pure methanol as the fuel with no need for dilution significantly raises the energy density. (c) 2006 The Electrochemical Society.