Lithium cycling performance in improved lithium hexafluoroarsenate/2-methyl tetrahydrofuran electrolytes

Lithium hexafluorarsenate/2-methyl tetrahydrofuran electrolytes have been prepared, purified, and evaluated using half-cell galvanostatic lithium cycling, cyclic voltammetry, plus colorimetric, gas chromatographic, and UV absorption techniques. Superior electrolytes have been prepared yielding reproducible cycling efficiencies in excess of 97 percent. Static aging trails at ambient temperature clearly demonstrate deterioration in cycling performance with time. This decline in performance is related to electrolyte degradation, possibly arising from the formation of peroxides. However, studies of various battery testing regimes on 1M LiAsF6/2Me-THF electrolyte support the system's battery potential with respect to both rate capability and shelf-life characteristics.