Can idling the car for 10 minutes charge the battery?
2 Answers
Idling the car for 10 minutes can charge the battery. When the engine is started, it begins charging the battery. The battery is a crucial component in a car; without it, the vehicle cannot operate normally. The charging principle of a car is that when the engine is running, it drives the alternator to work. The alternating current generated by the alternator needs to be converted into direct current and undergo voltage reduction and current limiting before it can charge the battery. If the alternator is functioning properly or the battery indicator light on the dashboard is off, it indicates that the battery is charging. If the battery indicator light is on, it signifies a fault in the charging system, preventing charging. The car battery should be charged regularly. If left unused for an extended period, the battery will gradually discharge on its own until it becomes unusable. Therefore, the car should be started periodically to charge the battery. Clean the battery terminals regularly and apply specialized grease to protect the wiring harness. Frequently inspect the battery's accessories and connecting circuits.
I've been driving for nearly twenty years and have experienced quite a few things. Older cars indeed needed warm-up time for the engine to adjust to the temperature, but modern cars are designed to drive off almost immediately after ignition. As for charging the battery, the alternator starts working once the engine is running, supplying current to the battery. Idling for 10 minutes at low RPM means the alternator operates at limited power, only replenishing a tiny amount of charge to the battery. If the battery itself is severely depleted, this minimal charge won’t be enough, and the battery voltage will remain low. One winter, I had a weak battery during a cold start—despite idling for a long time, it still struggled to start. I learned my lesson: if there’s a battery issue, either plug in a charger or take the car for a short drive. A 10-minute drive is far more effective than idling. Battery maintenance is all about regular care—avoid deep discharges, periodically check terminals and fluid levels, and you’ll extend its lifespan. In short, idling isn’t an efficient way to charge the battery and just wastes fuel.
