Can a Car Charge the Battery at Idle Speed?

[OCali]

Yes, a car can charge the battery at idle speed. When the battery charging indicator light on the dashboard is off, it indicates that the car is charging. If the light stays on, it means there is a charging fault, and you need to take the car to a repair shop for inspection. The car charging process essentially involves the engine driving the alternator to generate electricity, which is then rectified and regulated to provide a certain voltage to the battery. Typically, this voltage is slightly higher than the battery voltage to achieve constant voltage charging. At idle speed, although the engine speed is low, it still drives the alternator to work, so it can output a stable DC voltage. Since the battery power is relatively not that large, charging is possible at idle speed, but the charging speed will be slightly slower.