Battery management system for electric car

The invention Electric as car on the battery management system, in particular a DC / DC converter converts the voltage of the battery that supplies the voltage necessary for the system, a plurality of batteries is provided, the driving force by the power supplied from the battery a motor and an electric vehicle including a motor controller for controlling the motor for generating, each sensor module is connected to the battery and measuring the temperature and voltage; Charge-discharge circuit that is connected with the respective battery charging and discharging the battery is connected in accordance with an external control signal; And to remove the allowed voltage to discharge a respective battery for a certain period of time and controls the charging and discharging circuit at the time of controlling the charge-discharge circuit checks the remaining capacity of each of said each of said battery to charge the battery, and characterized in that a battery management unit by the information output from the sensor modules to calculate the slope of the curve that the battery voltage is restored to calculate the remaining capacity of each battery. In accordance with the present invention as described above and provided with a discharge circuit in each of the battery, during the discharge to eliminate allowed voltage, remaining capacity checked upon to accurately measure the remaining capacity of the correct battery, by using the slope of the curve determine the voltage value of the battery and, relative to the discharge voltage of the battery with high charging can reduce the voltage difference between the battery. Electric vehicle, the battery, the remaining capacity, the discharging, chip, display and tilt