Antennas 1 Battery management systems 1 Charging (batteries) 1 Equivalent circuit model 1 Equivalent circuits 1 Estimation 1 Experimental characteristics 1 Functional optimization Ions 1 Kalman filters 1 Lithium ions 1 Lithium-ion batteries 1 Lithium-ion battery pack 1 Open circuit voltage 1 Operating characteristics 1 State of charge estimation 1 State-of-charge estimation 1 Timing circuits 1 Unscented Kalman Filter 1 Unscented kalman filter 1 Working state 1 Working state monitoring 1