Low-temperature hydrothermal techniques were used to synthesize single crystals of Ag4V2O6F2. This previously unreported oxide fluoride phase was characterized by single-crystal X-ray diffraction and IR spectroscopy and was also evaluated as a primary lithium battery cathode. Crystal data: monoclinic, space group P2(1)/n (No. 14), with a = 8.4034(4) angstrom, b = 10.548(1) angstrom, c = 12.459(1) angstrom, beta = 90.314(2)degrees, and Z = 4. Ag4V2O6F2 (SVOF) exhibits two characteristic regions within the discharge curve, an upper plateau at 3.5 V, and a lower sloped region around 2.3 V from reduction of the vanadium oxide fluoride framework. The material has a nominal capacity of 251 mAh/g, with 148 mAh/g above 3 V. The upper discharge plateau at 3.5 V is nearly 300 mV over the silver reduction potential of the commercial primary battery material, Ag2V4O11 (SVO).