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The high level of charge delocalization of the Li(CF3SO2)2N anion reduces ion pairing in nonaqueous electrolytes. This overrides the higher viscosity of the imide-contalning solutions making the electrolytes much more conductive than those containing LiCF3SO3, especially ir~ low dielectric ether-based solvent systems commonly used in secondary lithium batteries. In more viscous solvent systems (1:1 propylene carbonate: 1,2-dimethoxyethane) or at low temperatures, the imide affords less of an advantage in conductivity due to the more important role of viscosity. The cyclic imide LirSO2-(CF2)4-SO2-N 1 gives more viscous and less conductive solutions than does Li(CF3SO2)2N. The degree of dissociation in 1:1 PC:DME appears to beThe number of lithium salts suitable for use in lithium high energy density batteries is rather limited. Generally most salts have been found to be either insoluble (most dianions, for example) or unstable to the lithium anode (1). Of those reported, many have poor stability and/or undesirable safety characteristics, particularly those often used in secondary lithium systems. LiC104 can lead to explosions under certain conditions (2, 3) and while LiAsFs is not in itself particularly toxic (4), there is considerable concern regarding both the effect of disposal of such cells on the environment and the toxicity of salt degradation products (5-8) which may be present in the cells. LiBF4 and LiPF6 have been used but are themselves not as stable as one would wish. LiCF3SO3 (lithium "triflate") is a more stable, safer salt which is commonly used in primary lithium cells. Its main disadvantage is the low conductivity of lithium triflate electrolytes.Recently, the availability of the lithium imide salt Li(CF3SO2)2N (lithium bistrifluoromethylsulfonyl imide) has sparked considerable interest in the lithium battery field. This salt is reported to offer much greater conductivity than can be attained with the triflate salt ( 9) and yet the imide appears to have good stability (9) an d safety characteristics. Thus, it would seem possible to use the imide salt to produce highly conductive electrolytes with stability and safety characteristics similar to those of triflate solutions. Such electrolyte s could improve the characteristics of both primary and secondary lithium batteries.Apart from some conductivity studies (9) reported by Koch et aI., very little conductivity and no viscosity data

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Application of thick-film printing technology to the fabrication of a zinc-alkaline battery was carried out in this study. Electrode inks were formulated using active materials in powdered form, poly͑ethene oxide͒ as binder, graphite as conductor, and water as solvent. Zinc-containing anodes and manganese dioxide cathodes were thick-film printed onto silver current collectors and assembled into cells using separator paper and potassium hydroxide electrolyte. The cells were cathode limited and had a theoretical capacity between 3 and 4 mAh. The highest discharge efficiency achieved was 97% of the theoretical capacity of the cathode at a discharge rate of 1 mA/cm 2 . Characterization of the electrochemical properties of the cell was carried out and assessed.