A 7.4% power conversion efficiency at air mass (AM) 1.5 full sunlight was reached with a mesoscopic solar cell employing a new binary ionic liquid electrolyte composed of 1-propyl-3-methylimiclazoliurn iodide and 1-ethyl-3-methylimidazolium tricyanomethanide in conjunction with the amphiphilic ruthenium complex NaRu(4-carboxylic acid-4′-carboxylate)(4,4′-dinonyl-2,2′-bipyridine)(NCS )(2), coded as Z-907Na. Ultramicroelectrode voltammetric, nanosecond laser transient absorbance, and photovoltaic measurements show that a high iodide concentration is required for dye regeneration to compete efficiently with charge recombination. A surprisingly fast reductive quenching process is turned on in pure iodide melts. This channel is unproductive, explaining the lower photocurrents observed under these conditions.