Modeling the Voltage Profile for LiFePO[sub 4]

The voltage profile of 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 for increasing discharge rates up to .