SYSTEM AND METHOD OF MANAGING BATTERY OF VEHICLE

A battery management system of a vehicle includes a first controller configured to control a power-on (IG ON) state and a power-off (IG OFF) state of the plurality of controllers, and a second controller including a real time clock (RTC) and configured to be woken up by directly receiving power from the secondary battery in every preset time period during a preset time calculated based on a count value provided from the RTC when a power-off state is started by the first controller and to monitor states of the main battery and the secondary battery.