Can a Car Charge While Idling in Place?
2 Answers
An idling car can charge the battery. Here is an introduction to charging while idling in place: 1. Explanation: As long as the car engine is running, it drives the alternator to work simultaneously. When idling, the voltage generated by the alternator, i.e., the potential difference, can meet the charging requirements. For household cars at idle, the alternator provides a voltage of 14V with a current of around 40A. 2. Precautions: When the battery charging indicator light on the dashboard is off, it means the car is charging. If it stays lit, it indicates a charging fault, and the car needs to be checked at a repair shop. When the ignition switch is turned on, the dashboard charging indicator light will briefly illuminate for a few seconds before turning off. This is the system performing a self-check, which is a normal condition.
I've been driving for over 20 years, and I have firsthand experience with idling a car to charge the battery. When idling, the engine is running and drives the alternator to generate electricity, which can charge the small battery a bit, but the efficiency is terribly low. I've tried it several times—idling for an hour barely charges the battery by less than 10%. Not only is it a waste of gasoline, but it also causes severe carbon buildup in the engine. In comparison, taking a short drive for about ten minutes charges the battery faster and cleaner. Especially in winter, when the battery is already weak, idling to charge is as slow as a turtle crawling—it's much easier to just go for a short drive. Plus, prolonged idling isn't good for the engine. My neighbor once had to spend a lot of money on repairs because of it. So my advice is: don't rely on idling to charge. Get into the habit of driving a short distance after starting the car—it saves fuel, is safer, and keeps the battery healthier for longer.
