Modeling the Voltage Profile for LiFePO[sub 4]

Abstract

The voltage profile of LiFePO 4 is described as the sum of three individual contributions: (i) the rapid segregation of lithium on the grain surface during the first stage of the intercalation process; (ii) the flat voltage region characteristic of a two-phase system; and (iii) the decay of the voltage to the end of the intercalation process. A general equation describing the voltage profile as a function of the degree of intercalation was developed for low discharge rate. The equation was successfully used to describe the voltage profile of LiFePO 4 for increasing discharge rates up to 10 C. © 2005 The Electrochemical Society. All rights reserved.