How long should the engine idle to charge a dead battery?
2 Answers
Charging time for a dead battery at idle speed: If the engine speed is 1500 rpm, charging for 20 minutes can provide enough power for the starter to start the engine once. Below is relevant information about car battery depletion: 1. Emergency measures: First, you need a set of jumper cables. Normally, such cables should be kept in the car for emergencies like this. Besides the cables, you'll also need assistance from another vehicle. Drive the other car over and park it facing your car. Open both hoods, then connect the positive terminals of both batteries with the jumper cable, and do the same for the negative terminals. 2. Knowledge introduction: Does the car come to a complete stop after turning off the engine? Traditionally, it's believed that once the car key is turned to the off position, all components stop working. However, when the engine temperature is too high, even if the car is turned off and the key is removed, the cooling system will automatically activate to cool down the engine. The cooling system will stop working automatically, usually within 3 to 5 minutes.
I've been dealing with this issue for a while – charging a depleted battery at idle does take quite some time. Generally, idling in place requires about 15 to 30 minutes, but this depends on the battery's discharge level and the vehicle model; older batteries may take even longer, possibly one to two hours. During charging, the engine speed maintains between 800-1000 RPM, and since the alternator output is relatively low, the efficiency isn't great. It's best to use a voltmeter for monitoring – if the voltage remains below 12V after 15 minutes, professional assistance is likely needed. Daily prevention is crucial, such as turning off headlights after engine shutdown to avoid excessive discharge. If this problem recurs frequently, it might indicate battery aging, and replacement shouldn't be delayed to prevent roadside breakdowns. Lastly, I'd suggest not just waiting idly – maybe tune into the radio to pass the time, but always prioritize safety first!
