Can the car charge the battery when it is turned on but not moving?
3 Answers
Yes, the car can charge the battery when it is turned on but not moving. The maintenance methods for car batteries are as follows: 1. Regularly check whether the small holes on the battery cover are ventilated; 2. Check whether the positive and negative terminals of the battery are oxidized; 3. Check whether there is any aging or short circuit in each part of the circuit; 4. Adjust the density of the electrolyte according to the standards for different regions and seasons; 5. Add distilled water or special replenishing fluid when the electrolyte is insufficient; 6. The total time for starting the car each time should not exceed 5 seconds; 7. Charge the battery in time when the ammeter shows insufficient power; 8. Start the car periodically when the battery is not used for a long time.
Yes, once the car is started and the engine is running, the alternator can work to charge the battery, even if the car isn't moving. I used to drive an old car and often encountered a dead battery. Parking and charging for half an hour could get it started, but this method isn't very efficient. When the engine is idling, the RPM is low, resulting in a slow charging speed. Moreover, it consumes fuel—like when I tested idling for an hour, it only charged about 20%, but the fuel consumption was equivalent to driving a few kilometers. Additionally, doing this long-term may affect the engine's lifespan and worsen carbon buildup issues. It's recommended to use this method only in emergencies, such as when the battery is just depleted, charging for 10-15 minutes should suffice. Normally, it's better to drive the car around to let the system cycle for more effective charging. A healthy battery makes the car run better.
That's correct. Once the car is started, the alternator begins generating electricity and can charge the battery regardless of whether the vehicle is moving or not. At repair shops, mechanics often refer to this as a short-term remedy, especially as a temporary measure for aging batteries. However, the efficiency is quite low: at idle speed, the current output is small, prolonging the charging time; it wastes fuel, increases costs, and may even accelerate wear on engine components. Personally, I recommend charging for no more than 10 minutes in emergencies—just enough to restore the starting power. If the battery is completely dead, it's better to borrow a charger or drive the car to allow the alternator to work at full load for more reliable charging. Remember to regularly check the battery's condition to prevent issues and save money in the long run.
