A METHOD AND SYSTEM FOR ESTIMATING BATTERY PROPERTIES IN A VEHICLE DRIVE SYSTEM

The invention relates to a system for and method of determining a model for estimating battery properties in a hybrid or electrical drive system () for a vehicle (), the method comprising: providing () a function approximator estimating a battery property as a function of two or more measured battery parameters; providing () a stream of measured battery parameter values as a function of time for a predetermined period to a predetermined battery cell model describing the relationship between the measured battery parameter and the battery property; determining (S) a battery property value using the cell model based on a selected portion of the stream of measured battery parameter values; determining (S) if a predetermined condition for the selected portion of the stream of measured battery parameter values is fulfilled; and if (S) the predetermined condition is fulfilled, updating (S) the function approximator based on the battery property value determined by the cell model.