Method for determining state quantities of high voltage traction battery for e.g. electric vehicle, involves determining aging state of battery based on computed state of charge, internal resistance and cell capacitance of battery

摘要

The method involves computing a state of charge of a battery by a first Kalman filter based on an assumption that cell capacitance is constant. Convergence time of the state of charge is determined. Internal resistance (Ri) of lithium ion cells of the battery is computed by a second Kalman filter based on the assumption that the cell capacitance is constant. The cell capacitance is computed by a third Kalman filter based on an inverse time lag of the convergence time. An aging state of the battery is determined based on the computed state of charge, the resistance and the cell capacitance.