The stability of water-stable lithium metal in aqueous acetic acid solution was examined as an anode in a lithium-air rechargeable battery. The water-stable lithium anode consisted of a water-stable glass-ceramic Li1+x+yTi2-xAlxSiyP3-yO12 (LTAP), a poly(ethylene oxide) (PEO)-based electrolyte with Li(CF3SO2)(2)N (LiTFSI), and lithium metal. The LTAP immersed in CH3COOH (HAc)-H2O-saturated CH3COOLi (LiAc) solutions at 50 degrees C for several weeks showed no change in the X-ray diffraction pattern and showed a slight decrease in the electrical conductivity. The water-stable lithium anode, Li/PEO18LiTFSI/LTAP, showed a total resistance of 164 cm(2) at 60 degrees C after being immersed in HAc (90 vol %)-H2O (10 vol %)-saturated LiAc for 1 week. The Li/PEO18LiTFSI/LTAP/HAc-H2O-LiAc/Pt black air cell had a low polarization for lithium dissolution and deposition at a current density of 1 mA cm(-2). A prototype lithium-air cell using a carbon air electrode with a platinum catalyst showed a good charge and discharge cycle performance, and about 30% of acetic acid in the cell was consumed and recovered in the charge and discharge process.