Addressing the Surface Concentration Discontinuity of the Core-Shell Model for Lithium Iron Phosphate Batteries

Abstract

This communication addresses the limitation of core-shell enhanced single particle model for lithium iron-phosphate recently published by the authors. In this model, the positive particle surface concentration has a jump discontinuity that forms at the transition from the one-phase to the two-phase region, which is responsible for the positive particle overpotential and open circuit potential jumps seen in the cell output voltage. Such a discontinuity is eliminated by proposing a modification of the core-shell enhanced single particle model based on the bulk-normalized lithium concentration. Simulation results show the effectiveness of the new solution against the previously published one.