An interlaced strategy for open circuit voltage and capacity estimation for lithium-ion batteries

Performance of battery energy management strategies are largely affected by battery parameters which change depending on real usage during its life. In fact, variations of capacity, open circuit voltage characteristic and internal resistance influence the battery management when cycled. In this paper a technique for the simultaneous real-time co-estimation of the battery parameters is proposed. The estimator consists of a set of interconnected subsystems grounded on the integration of recursive least square techniques and a state of charge observer. The estimator effectiveness is verified by using experiments with charging and discharging cycles of a Li-ion cell during its life.