The State of Charge Estimating Methods for Battery: A Review

Table 1

Classification of SOC estimating mathematical methods.

Categories	Mathematical methods
Direct measurement	(i) Open circuit voltage method
	(ii) Terminal voltage method
	(iii) Impedance method
	(iv) Impedance spectroscopy method
Book-keeping estimation	(i) Coulomb counting method
	(ii) Modified Coulomb counting method
Adaptive systems	(i) BP neural network
	(ii) RBF neural network
	(iii) Support vector machine
	(iv) Fuzzy neural network
	(v) Kalman filter
Hybrid methods	(i) Coulomb counting and EMF combination
	(ii) Coulomb counting and Kalman filter combination
	(iii) Per-unit system and EKF combination