A battery model identification method of a battery capable of being discharged and charged, the method comprising the steps of: setting a battery model of the battery which has a plurality of resistance components (Rb, R1, R2, R3) and capacitance components (C1, C2, C3) as parameters,; inputting an electric current input into the battery; measuring a terminal voltage of the battery when the signals are inputted; identifying the battery model based on the electric current input inputted to the battery and a measured result of the terminal voltage; calculating frequency characteristics of the battery; and estimating the parameters of the battery model based on the calculated frequency characteristics, wherein the electric current input is produced by M-sequence signals with predetermined different frequency components; wherein identifying the battery model comprises the steps of: extracting and synthesising data on respective frequency response in a predetermined frequency range; and identifying the battery model based on the data on the frequency response; characterised by calculating SOC by accumulating output current of the battery; and calculating open circuit voltage based on the SOC, and wherein the system identification uses overvoltage which is calculated by subtracting the open circuit voltage from the terminal voltage of the battery; and identifying the battery model, using the overvoltage. setting a battery model of the battery which has a plurality of resistance components (Rb, R1, R2, R3) and capacitance components (C1, C2, C3) as parameters,; inputting an electric current input into the battery; measuring a terminal voltage of the battery when the signals are inputted; identifying the battery model based on the electric current input inputted to the battery and a measured result of the terminal voltage; calculating frequency characteristics of the battery; and estimating the parameters of the battery model based on the calculated frequency characteristics, wherein the electric current input is produced by M-sequence signals with predetermined different frequency components; wherein identifying the battery model comprises the steps of: extracting and synthesising data on respective frequency response in a predetermined frequency range; and identifying the battery model based on the data on the frequency response; characterised by calculating SOC by accumulating output current of the battery; and calculating open circuit voltage based on the SOC, and wherein the system identification uses overvoltage which is calculated by subtracting the open circuit voltage from the terminal voltage of the battery; and identifying the battery model, using the overvoltage. extracting and synthesising data on respective frequency response in a predetermined frequency range; and identifying the battery model based on the data on the frequency response; characterised by calculating SOC by accumulating output current of the battery; and calculating open circuit voltage based on the SOC, and wherein the system identification uses overvoltage which is calculated by subtracting the open circuit voltage from the terminal voltage of the battery; and identifying the battery model, using the overvoltage.