Modeling and Optimization of Li-Alloy-Metal-Sulfide Molten Salt Batteries.

摘要

A computer model for the LiAl/FeS/sub x/ molten-salt battery system (prismatic geometry), which uses input data from experimental test cells, is presented. Optimizations of the negative-to-positive capacity ratio and the number of electrodes per cell are considered. The LiAl/FeS, LiAl/FeS sub 2 (two-plateau operation), and LiAl/FeS sub 2 (upper-plateau operation) battery systems are compared. (Upper-plateau operation refers to complete discharge of FeS sub 2 to Li sub 2 FeS sub 2 , and two-plateau operation refers to complete discharge to Fe and Li sub 2 S.) While the specific energies are similar for all three systems, the specific power near the end of discharge is highest for the upper-plateau FeS sub 2 system. A similar model for a multi-electrode LiAl/FeS sub 2 cylindrical cell (upper-plateau operation) is also presented. A simplified version of this model, which does not account for the bus and post resistances, is used to show that the experimental data currently available in the literature are not appropriate for use with this model. In spite of this disappointing conclusion, the effects of the positive current collector radius, the cell height, and the number of positive electrodes on specific energy and specific power are examined. 43 refs., 19 figs., 3 tabs. (ERA citation 14:007863)