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.
Novel Design and Fabrication of Thermal Battery Cathodes Using Thermal Spray
Li-Alloy/FeS 2 thermal batteries are the predominant thermal battery chemistry today. Conventional electrodes are fabricated by cold pressing of powders. A better means of providing thin electrodes would dramatically increase volumetric and gravimetric energy densities and cost efficiency of thermal batteries. In this study, experiments were conducted on fabricating the cathode via high-velocity oxygen-fuel (HVOF) and dc-arc plasma thermal spray technique. The deposited films were characterized by cross-section examination using Scanning Electron Microscopy (SEM) and X-ray Diffraction. The thermal decomposition of pyrite was suppressed by a proprietary additive. The electrochemical test results showed that pyrite cathodes prepared by dc-arc plasma spraying with additives demonstrated better performance compared traditional pressed-powder electrodes.
Hypervelocity impact fusion—a technical note
A very simple outline of the engineering theory for the implementation of hypervelocity oxygen fuel (HVOF) and hypervelocity air fuel (HVAF) processes is presented. Several calculations show that a condition can be reached where the impact energy of these processes can be optimized to produce a new class of coatings termed “hypervelocity impact fusion” coatings. The microstructures of these coatings exhibit minimum oxidation and very good bonding to the substrate.