Six lithium salts of tris- and tetrakis(polyfluoroalkoxy)aluminate superweak anions have been studied for their potential use as battery electrolytes. Four of the six are based on the formula LiAl(OCR(CF3)(2))(4) (R = H, Me, CF3, Ph); the other two are LiAl(OCH2CF3)(4) and LiAlF(OCPh(CF3)(2))(3). The thermally stable electrolytes LiAl(OCH(CF3)(2))(4) and LiAl(OCPh(CF3)(2))(4) were not oxidized at potentials less than or equal to 5.0 V vs. Li+/0 in dimethoxyethane (DME) or in 50: 50% ethylene carbonate: dimethylcarbonate (EC: DMC). The LiAl(OCH(CF3)(2))(4) electrolyte was not reduced at 0 V vs. Li+/0 in DME. Neither LiAl(OCH(CF3)(2))(4) nor LiAl(OCPh(CF3)(2))(4) promoted the corrosion of aluminum at 5.0 V vs. Li+/0. The electrolyte LiAl(OCH(CF3)(2))(4) underwent efficient, reversible reductive intercalation of Li+ with MCMB carbon or LiCoO2 electrodes over the potential ranges 0-2 and 2.4-4.8 V, respectively, vs. Li+/0, but did not react in any other way with these electrode materials. The conductivities of some of the LiAl(ORF)(4) electrolytes in DME or in EC: DMC were high enough for them to be considered as potential replacements for LiPF6 in primary and secondary lithium batteries. (C) 2004 The Electrochemical Society.