Can a car charge its battery by idling for 10 minutes?
3 Answers
Idling for ten minutes can charge the battery by approximately 5%. Here are the relevant details: Introduction: Starting the car while stationary can charge the battery. After the car is started, the alternator and voltage regulator assist in continuously charging the battery. However, since the engine is not operating under normal working conditions, relying solely on idle speed results in relatively low power output. Battery: The car battery, also known as a storage battery, is a type of battery that primarily works by converting chemical energy into electrical energy. The battery requires regular charging. If a car is not driven for an extended period, it needs to be started to charge the battery, as prolonged inactivity will cause the battery to gradually self-discharge until it is depleted. Cars should not be exposed to high-temperature or low-temperature environments for long periods. High temperatures can cause the battery to overheat, affecting its charge capacity, while low temperatures significantly reduce the battery's capacity compared to normal conditions.
Starting the car for 10 minutes can charge the battery, which I've tried often. When you start the engine, the alternator begins working to charge the battery, but the effect is minimal. At idle speed, the power generation is low, and 10 minutes of charging may only replenish 10-20%, which isn't enough to revive a depleted battery. For example, during cold winter starts, the battery is even harder to fully charge. If the battery is aging, charging becomes slower. Moreover, prolonged idling can lead to carbon buildup in the engine, doing more harm than good. I recommend driving around after starting—higher RPMs charge the battery faster and save fuel. Regularly checking battery health is crucial to avoid last-minute failures. In short, it can charge, but don't expect it to solve the problem—it's too limited.
I've been driving for decades. Starting the car and idling for 10 minutes does charge the battery, as the alternator starts working immediately. However, the amount is pitifully small. At idle, the engine speed is only a few hundred RPM, resulting in low charging efficiency. The electricity generated in 10 minutes might only be enough to support a short ignition attempt. If the battery is severely depleted, this won't be sufficient. Experience tells me winter conditions are worse - battery capacity shrinks and charging becomes extremely slow. I've encountered completely dead batteries where idling for hours had no effect. For safety, I recommend moving the car slightly after starting it, or better yet, using a proper battery charger. Don't make this a habit - idling not only wastes fuel but also causes carbon buildup that damages the engine. Prolonged issues from this practice can lead to major headaches.
