Post-test examinations of Li-Al/FeS/sub x/ secondary cells

Reactions of FeS2, CoS2, and NiS2 Electrodes in Molten LiCl ‐ KCl Electrolytes

“…Significant amounts of a water-soluble Mn species have been detected in the sulfate salt remaining on the surface of prototype Navy blade alloys, which contain small (< 1% ) percentages of manganese, after low temperature (704~ burner rig testing (6). This Mn species is most likely a mixed sulfate from the MnSO~-Na2SO~ system (eutectic mp 645~ (7), and the question is raised as to whether such Mn,Na sulfates might reduce the LTHC performance of the prototype alloys.…”

Li-alloy/FeS cell design and analysis report

“…4 Metallographic and scanning electron microscopic examinations show that the the Li-Al alloy, when cycled electrochemically, forms a porous, interconnected (skeletal) microstructure. 5 This type of microstructure is formed regardless of whether the starting material is Li-Al particles, Li-Al cast plates, or aluminum wire charged electrochemically with lithium. This porous microstructure appears ideal for high-rate, efficient electrodes.…”

“…In-cell test data for low-carbon steel in the FeS electrode show an initial period of rapid corrosion, after which the rate drops markedly. 5 This behavior is attributed to the generation of iron particles in the electrode matrix by intergranular corrosion, which tends to protect the current-collector structure from further attack.…”

Low-hazard metallography of moisture-sensitive electrochemical cells

“…Solvent vapours are the primary safety concern during nonaqueous grinding and polishing. Early work on polishing alkali metals typically used kerosene as the lubricating fluid (Battles et al ., 1980; Vander Voort, 1984). The less flammable propylene carbonate has also been used (Dallek et al ., 1978).…”

“…Some battery components, such as lithium and lithium alloys, are so hydroscopic that they even react with standard atmospheric levels of water vapour. Metallographic sample preparation of battery components can be conducted in a glove box (Dallek et al, 1978;Battles et al, 1980), but an industrial dry room environment with a dew point of less than −30 • C (pH 2 O < 375 ppm) has several advantages. Battery dissection equipment, such as lathes and cut off saws, can be placed Correspondence to: D. E. Wesolowski, Power Sources Technology Group, Sandia National Laboratories, U.S.A. Tel: +1-505-845-0614; fax: +1-505-844-6972; e-mail: dewesol@sandia.gov in a dry room.…”