Mathematical Modeling of LiAl / LiCl , KCl / FeS Cells

Abstract

The thermodynamic equilibrium behavior and the nonequilibrium behavior of high temperature cells are examined. A consistent set of thermodynamic data for the open‐circuit cell potential, and its dependence on temperature, initial electrolyte composition, and utilization are presented. The possible reaction sequences of the electrode are examined. A nonequilibrium computer model of the cell is discussed, and results are focused on the case with as the intermediate discharge product of the electrode. The model is used to predict cell potential and electrolyte composition changes throughout the cell as a function of state of discharge. The model predicts that the clogging of pores by precipitation can limit the utilization of the electrode during discharge. Such clogging appears to occur, however to a lesser extent, in experimental cells. If expansion of the electrode during discharge is taken into consideration, the predicted utilization approaches that of experimental cells.