Similarly, you may ask, do car batteries charge while idling?
So, to put it simply, yes, MOST vehicles willcharge the battery, albeit slowly, at idle RPM.Be careful of placing large electrical loads on the car atidle, however, as it could actually cause you to drain yourbattery, even though the engine is running.
Beside above, can a completely dead battery be recharged? While your vehicle's alternator can keep ahealthy battery charged, it was never designed tocompletely recharge a dead unit. These chargingdevices are designed to safely restore a dead battery tofull charge. Most of the time, you don't even have to remove thebattery from your vehicle.
Besides, how long does it take the alternator to charge the battery?
about 2 hours
Does revving engine charge battery faster?
But when your engine turns faster, theengine's alternator also turns faster. That way, allof the alternator's power can be directed to recharging thebattery. Once the car starts, you CAN rev it up tocharge the battery faster, but the best way todo that is to just drive it.