An accelerated sol-gel process with water/vapor management was developed here to synthesize SiO2-P2O5 glass electrolytes for shortening the gelation time and enhancing their proton conductivities. The gelation time needed is shortened from I to 6 months in the Wang et al.'s report [Mater. Lett. 42 (2000) 225] to about 3 days successfully in the developed process. The gelation reactions in the sol-gel process for the synthesis Of SiO2-P2O5 glass electrolytes were investigated by in situ FTIR spectroscopy. Types of water involving free/hydrogen bonded/strong hydrogen bonded water and hydroxyl group in the synthesized SiO2-P2O5 glass electrolytes were determined by TGA and in situ FTIR. A SiO2-P2O5 glass electrolyte with a methanol permeability of 2.1 x 10(-9) cm(2)/s and high proton conductivity (9.45 x 10(-3) S/cm) was obtained by the developed process. (C) 2004 Elsevier B.V. All rights reserved.