Material Balance Modification in One‐Dimensional Modeling of Porous Electrodes

The material balance used previously in one‐dimensional mathematical models of porous electrodes is invalid when there is a non‐zero volume change associated with the reaction. It is shown here how the material balance should be modified either to account for a loss in volume, or to account for an inflow of electrolyte from the header into the active pores. A one‐dimensional mathematical model is used to illustrate the effect of this correction on the prediction of the delivered capacity and the electrolyte concentration in a lithium/thionyl chloride primary battery.