Traditional vehicles have extremely strict quiescent current requirements. The quiescent current is about 15mA after the whole vehicle is powered off. The high voltage is powered off after the new energy vehicle is parked (the high voltage will be cut off when the OFF gear is turned on). BMS has a special design. , It can take electricity from the high-voltage battery and turn it into a low-voltage 12V for the vehicle to use, which ensures that the battery does not lose power. The price paid for this is that even if the car is parked, the high-voltage battery needs to lose about 1% of its power every day. You may ask, will this not drain the high-voltage power. Of course, a corresponding strategy has also been made – when the power is below 20%, some functions will be disabled.