MATHEMATICAL-MODELING OF THE SODIUM IRON CHLORIDE BATTERY

A mathematical model of the sodium/iron chloride battery containing a molten AlCl3-NaCl electrolyte is presented. A cylindrical cell consisting of a positive iron electrode, an electrolyte reservoir, a separator, and a negative sodium electrode is considered. The analysis uses concentrated-solution theory within the framework of a macroscopic porous electrode model. The effects of the state of discharge, the cell temperature, the precipitation and dissolution rates of NaCl, and the current density on the current-potential relation during the discharge and charge cycles are discussed. The major influences on battery performance are changes in porosity and component volume fractions during cycling. © 1990, The Electrochemical Society, Inc. All rights reserved.