Evaluation of plasma-sprayed CoS2 cathodes for thermal batteries
Conventional electroactive stack components in thermal batteries are constructed from pressed-powder parts. These include the anode, separator, and cathode pellets (discs). Pressing parts that are less than 0.010" thick is difficult. The use of plasma spray to deposit thin CoS/sub 2/ cathode films onto a stainless steel substrate was examined as an alternative to pressed-powder cathodes. The plasma-sprayed electrodes were tested in single cells under isothermal conditions and constant-current discharge over a temperature range of 400/spl deg/C to 550/spl deg/C using standard LiSi anodes and separators based on the LiCl-KCl eutectic. Similar tests were conducted with cells built with conventional pressed-powder cathodes, which were tested under the same conditions for comparative purposes. This paper presents the results of those tests.
, S + W 3 ZOO 0-2 % 2 LC Review of US Nanocorp @-SNL Joint Development of Thermal-Sprayed Thin-Film Cathodes for Thermal Batteries
Theuse of plasma spray to deposit thin metal-sulfide cathode films is described in this paper. Conventional electroactive stack components in thermal batteries are constructed from pressed-powder parts that are difficult to fabricate in large diameters in thicknesses <0.010”. Plasma-sprayed electrodes do not stier from this difficulty, allowing greater energy densities and specific energies to be realized. Various co-spraying agents have been found suitable for improving the mechanical as well as electrochemical properties of plasma-sprayed cathodes for thermal batteries. These electrodes genemlly show equal or improved performance over conventional pressed-powder electrodes. A number of areas for fbture growth and development of plasma;pray technology will be discussed.
Phase Relationships in Positive Electrodes of High Temperature Li ‐ Al / LiCl ‐ KCl / FeS2 Cells
The phases present in FeS/sub 2/ electrodes operated in LiCl-KCl eutectic electrolyte were determined by x-ray diffraction and by metallographic examination. The phases were FeS/sub 2/, KFeS/sub 2/, Li/sub 3/Fe/sub 2/S/sub 4/, Li/sub 2.33/Fe/sub 0.67/S/sub 2/, Fe/sub 1-x/S, Li/sub 2/FeS/sub 2/, LiK/sub 6/Fe/sub 24/S/sub 26/Cl, Li/sub 2/S, and Fe. The metallographic and crystallographic characteristics of these phases are presented. The sequence of Li-Fe-S phases in the FeS/sub 2/ electrode was in accord with the sequence predicted from the equilibrium Li-Fe-S phase diagram. Two of the Li-Fe-S phases found at room temperature (Li/sub 2.33/Fe/sub 0.67/S/sub 2/ and Li/sub 2/FeS/sub 2/) result from decomposition on cooling of a solid solution phase: Li/sub 2+x/Fe/sub 1-x/S/sub 2/ (O/less than equivalent to/x/less than equivalent to/0.33). This work is pertinent to vehicle propulsion and off-peak energy storage. 18 refs.