We synthesized CH3OH from CO2 and H2O on a copper cathode in the high-pressure CO2-C2H3OH-H2O-LiCl system. Methanol was the only product of Cd, reduction detected in the electrolytic solution, with a maximum current efficiency for methanol production of 40% at a current density of 9 mA/cm(2) and potential of -1.1 V vs. Ag/AgCl. This is the highest efficiency yet reported for methanol production at this current density. Current-potential curves shifted in the positive potential direction with increasing temperature and with increasing CO2 pressure up to approximately 60 atm. When the applied potential is more negative than about -1.2 V vs. Ag/AgCl, the current density decreases dramatically with time. Electrolyte conductivity in this system increases with increasing temperature, increasing concentration of LiCl, and decreasing CO2 pressure.