The invention provides methods, devices and non-transitory tangible computer-readable storage media for estimating a state of charge of a battery and extracting a charging curve of the battery. The method for estimating the state of charge of the battery includes estimating a first state of charge of the battery; determining a charging curve that conforms to the present charging scenario, wherein the present charging scenario is characterized by at least one of parameters including an ambient temperature, a charging rate, an internal resistance, a state of health, a lifespan, and an open circuit voltage of the battery; and correcting the first state of charge according to the charging curve to obtain a final state of charge of the battery.