Safety Studies of Lithium-Sulfur Dixoide Cells

摘要

The objective of this program was to study the relationship between the various design parameters of Li/SO2 cells and their abuse resistance for the purpose of developing approaches to the design of cells with an increased abuse resistance. The investigations were focussed on hermetically sealed D cells. Three factors were found to affect the abuse resistance of the cells significantly: (1) the Li/SO2 ratio, (2) the anode/cathode capacity ratio, and (3) the intrinsic rate capability of the cathode. Cells incorporating the most favorable combination of these factors were found to have a significantly greater abuse resistance than the standard production cells as determined by the behavior of the cells under constant current cell reversal at various discharge rates. The experimental work showed that for any particular cell design abusive conditions can be found that render the cells unsafe. It also showed that the abuse resistance of the cells can be even further increased by the development of truly high rate cathode structures and electrode configurations, so much so that in all probability the cells may be rendered safe under all conditions encountered in field use and storage. (Author)