RESUMO
Magnesium metal is an ideal rechargeable battery anode material because of its high volumetric energy density, high negative reduction potential and natural abundance. Coupling Mg with high capacity, low-cost cathode materials such as electrophilic sulphur is only possible with a non-nucleophilic electrolyte. Here we show how the crystallization of the electrochemically active species formed from the reaction between hexamethyldisilazide magnesium chloride and aluminum trichloride enables the synthesis of a non-nucleophilic electrolyte. Furthermore, crystallization was essential in the identification of the electroactive species, [Mg(2)(µ-Cl)(3)·6THF](+), and vital to improvements in the voltage stability and coulombic efficiency of the electrolyte. X-ray photoelectron spectroscopy analysis of the sulphur electrode confirmed that the electrochemical conversion between sulphur and magnesium sulfide can be successfully performed using this electrolyte.
RESUMO
Three hundred twenty zinc-air batteries representing four manufacturers (Energizer, Power One, Duracell, and Ray-O-Vac) and four cell sizes (10, 312, 13, and 675) were exposed in a salt spray fog apparatus for 2.5, 5.5, 24, 48, and 72 hours. At the conclusion of each exposure, the batteries were rated blindly for the presence of rust by four experienced audiologists using a four point rating scale. Results revealed significant differences in the rating of rust across the four manufacturers and duration of exposure. No statistically significant difference was found across cell size. Also, the correlation between raters was exceptionally high indicating that each audiologist rated the presence of rust for each battery in a very similar manner. Scanning electron microscopy (SEM), energy dispersive x-ray spectroscopy (EDS), and Auger electron spectroscopy (AES) techniques were applied and provided answers for the observed differences in rust between the four manufacturers.
